fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/cleancache.h>
  43 #include <linux/uaccess.h>
  44 #include <linux/iversion.h>
  45
  46 #include <linux/kthread.h>
  47 #include <linux/freezer.h>
  48
  49 #include "ext4.h"
  50 #include "ext4_extents.h"       /* Needed for trace points definition */
  51 #include "ext4_jbd2.h"
  52 #include "xattr.h"
  53 #include "acl.h"
  54 #include "mballoc.h"
  55 #include "fsmap.h"
  56
  57 #define CREATE_TRACE_POINTS
  58 #include <trace/events/ext4.h>
  59
  60 static struct ext4_lazy_init *ext4_li_info;
  61 static struct mutex ext4_li_mtx;
  62 static struct ratelimit_state ext4_mount_msg_ratelimit;
  63
  64 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  65                              unsigned long journal_devnum);
  66 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  67 static int ext4_commit_super(struct super_block *sb, int sync);
  68 static int ext4_mark_recovery_complete(struct super_block *sb,
  69                                         struct ext4_super_block *es);
  70 static int ext4_clear_journal_err(struct super_block *sb,
  71                                   struct ext4_super_block *es);
  72 static int ext4_sync_fs(struct super_block *sb, int wait);
  73 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  74 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  75 static int ext4_unfreeze(struct super_block *sb);
  76 static int ext4_freeze(struct super_block *sb);
  77 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  78                        const char *dev_name, void *data);
  79 static inline int ext2_feature_set_ok(struct super_block *sb);
  80 static inline int ext3_feature_set_ok(struct super_block *sb);
  81 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  82 static void ext4_destroy_lazyinit_thread(void);
  83 static void ext4_unregister_li_request(struct super_block *sb);
  84 static void ext4_clear_request_list(void);
  85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  86                                             unsigned int journal_inum);
  87
  88 /*
  89  * Lock ordering
  90  *
  91  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  92  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  93  *
  94  * page fault path:
  95  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  96  *   page lock -> i_data_sem (rw)
  97  *
  98  * buffered write path:
  99  * sb_start_write -> i_mutex -> mmap_sem
 100  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 101  *   i_data_sem (rw)
 102  *
 103  * truncate:
 104  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
 105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
 106  *   i_data_sem (rw)
 107  *
 108  * direct IO:
 109  * sb_start_write -> i_mutex -> mmap_sem
 110  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
 111  *
 112  * writepages:
 113  * transaction start -> page lock(s) -> i_data_sem (rw)
 114  */
 115
 116 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 117 static struct file_system_type ext2_fs_type = {
 118         .owner          = THIS_MODULE,
 119         .name           = "ext2",
 120         .mount          = ext4_mount,
 121         .kill_sb        = kill_block_super,
 122         .fs_flags       = FS_REQUIRES_DEV,
 123 };
 124 MODULE_ALIAS_FS("ext2");
 125 MODULE_ALIAS("ext2");
 126 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 127 #else
 128 #define IS_EXT2_SB(sb) (0)
 129 #endif
 130
 131
 132 static struct file_system_type ext3_fs_type = {
 133         .owner          = THIS_MODULE,
 134         .name           = "ext3",
 135         .mount          = ext4_mount,
 136         .kill_sb        = kill_block_super,
 137         .fs_flags       = FS_REQUIRES_DEV,
 138 };
 139 MODULE_ALIAS_FS("ext3");
 140 MODULE_ALIAS("ext3");
 141 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 142
 143 /*
 144  * This works like sb_bread() except it uses ERR_PTR for error
 145  * returns.  Currently with sb_bread it's impossible to distinguish
 146  * between ENOMEM and EIO situations (since both result in a NULL
 147  * return.
 148  */
 149 struct buffer_head *
 150 ext4_sb_bread(struct super_block *sb, sector_t block, int op_flags)
 151 {
 152         struct buffer_head *bh = sb_getblk(sb, block);
 153
 154         if (bh == NULL)
 155                 return ERR_PTR(-ENOMEM);
 156         if (buffer_uptodate(bh))
 157                 return bh;
 158         ll_rw_block(REQ_OP_READ, REQ_META | op_flags, 1, &bh);
 159         wait_on_buffer(bh);
 160         if (buffer_uptodate(bh))
 161                 return bh;
 162         put_bh(bh);
 163         return ERR_PTR(-EIO);
 164 }
 165
 166 static int ext4_verify_csum_type(struct super_block *sb,
 167                                  struct ext4_super_block *es)
 168 {
 169         if (!ext4_has_feature_metadata_csum(sb))
 170                 return 1;
 171
 172         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 173 }
 174
 175 static __le32 ext4_superblock_csum(struct super_block *sb,
 176                                    struct ext4_super_block *es)
 177 {
 178         struct ext4_sb_info *sbi = EXT4_SB(sb);
 179         int offset = offsetof(struct ext4_super_block, s_checksum);
 180         __u32 csum;
 181
 182         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 183
 184         return cpu_to_le32(csum);
 185 }
 186
 187 static int ext4_superblock_csum_verify(struct super_block *sb,
 188                                        struct ext4_super_block *es)
 189 {
 190         if (!ext4_has_metadata_csum(sb))
 191                 return 1;
 192
 193         return es->s_checksum == ext4_superblock_csum(sb, es);
 194 }
 195
 196 void ext4_superblock_csum_set(struct super_block *sb)
 197 {
 198         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 199
 200         if (!ext4_has_metadata_csum(sb))
 201                 return;
 202
 203         es->s_checksum = ext4_superblock_csum(sb, es);
 204 }
 205
 206 void *ext4_kvmalloc(size_t size, gfp_t flags)
 207 {
 208         void *ret;
 209
 210         ret = kmalloc(size, flags | __GFP_NOWARN);
 211         if (!ret)
 212                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 213         return ret;
 214 }
 215
 216 void *ext4_kvzalloc(size_t size, gfp_t flags)
 217 {
 218         void *ret;
 219
 220         ret = kzalloc(size, flags | __GFP_NOWARN);
 221         if (!ret)
 222                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 223         return ret;
 224 }
 225
 226 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 227                                struct ext4_group_desc *bg)
 228 {
 229         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 230                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 231                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 232 }
 233
 234 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 235                                struct ext4_group_desc *bg)
 236 {
 237         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 238                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 239                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 240 }
 241
 242 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 243                               struct ext4_group_desc *bg)
 244 {
 245         return le32_to_cpu(bg->bg_inode_table_lo) |
 246                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 247                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 248 }
 249
 250 __u32 ext4_free_group_clusters(struct super_block *sb,
 251                                struct ext4_group_desc *bg)
 252 {
 253         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 254                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 255                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 256 }
 257
 258 __u32 ext4_free_inodes_count(struct super_block *sb,
 259                               struct ext4_group_desc *bg)
 260 {
 261         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 262                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 263                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 264 }
 265
 266 __u32 ext4_used_dirs_count(struct super_block *sb,
 267                               struct ext4_group_desc *bg)
 268 {
 269         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 270                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 271                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 272 }
 273
 274 __u32 ext4_itable_unused_count(struct super_block *sb,
 275                               struct ext4_group_desc *bg)
 276 {
 277         return le16_to_cpu(bg->bg_itable_unused_lo) |
 278                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 279                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 280 }
 281
 282 void ext4_block_bitmap_set(struct super_block *sb,
 283                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 284 {
 285         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 286         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 287                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 288 }
 289
 290 void ext4_inode_bitmap_set(struct super_block *sb,
 291                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 292 {
 293         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 294         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 295                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 296 }
 297
 298 void ext4_inode_table_set(struct super_block *sb,
 299                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 300 {
 301         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 302         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 303                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 304 }
 305
 306 void ext4_free_group_clusters_set(struct super_block *sb,
 307                                   struct ext4_group_desc *bg, __u32 count)
 308 {
 309         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 310         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 311                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 312 }
 313
 314 void ext4_free_inodes_set(struct super_block *sb,
 315                           struct ext4_group_desc *bg, __u32 count)
 316 {
 317         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 318         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 319                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 320 }
 321
 322 void ext4_used_dirs_set(struct super_block *sb,
 323                           struct ext4_group_desc *bg, __u32 count)
 324 {
 325         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 326         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 327                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 328 }
 329
 330 void ext4_itable_unused_set(struct super_block *sb,
 331                           struct ext4_group_desc *bg, __u32 count)
 332 {
 333         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 334         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 335                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 336 }
 337
 338 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
 339 {
 340         time64_t now = ktime_get_real_seconds();
 341
 342         now = clamp_val(now, 0, (1ull << 40) - 1);
 343
 344         *lo = cpu_to_le32(lower_32_bits(now));
 345         *hi = upper_32_bits(now);
 346 }
 347
 348 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
 349 {
 350         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
 351 }
 352 #define ext4_update_tstamp(es, tstamp) \
 353         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 354 #define ext4_get_tstamp(es, tstamp) \
 355         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
 356
 357 static void __save_error_info(struct super_block *sb, const char *func,
 358                             unsigned int line)
 359 {
 360         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 361
 362         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 363         if (bdev_read_only(sb->s_bdev))
 364                 return;
 365         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 366         ext4_update_tstamp(es, s_last_error_time);
 367         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 368         es->s_last_error_line = cpu_to_le32(line);
 369         if (!es->s_first_error_time) {
 370                 es->s_first_error_time = es->s_last_error_time;
 371                 es->s_first_error_time_hi = es->s_last_error_time_hi;
 372                 strncpy(es->s_first_error_func, func,
 373                         sizeof(es->s_first_error_func));
 374                 es->s_first_error_line = cpu_to_le32(line);
 375                 es->s_first_error_ino = es->s_last_error_ino;
 376                 es->s_first_error_block = es->s_last_error_block;
 377         }
 378         /*
 379          * Start the daily error reporting function if it hasn't been
 380          * started already
 381          */
 382         if (!es->s_error_count)
 383                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 384         le32_add_cpu(&es->s_error_count, 1);
 385 }
 386
 387 static void save_error_info(struct super_block *sb, const char *func,
 388                             unsigned int line)
 389 {
 390         __save_error_info(sb, func, line);
 391         if (!bdev_read_only(sb->s_bdev))
 392                 ext4_commit_super(sb, 1);
 393 }
 394
 395 /*
 396  * The del_gendisk() function uninitializes the disk-specific data
 397  * structures, including the bdi structure, without telling anyone
 398  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 399  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 400  * This is a kludge to prevent these oops until we can put in a proper
 401  * hook in del_gendisk() to inform the VFS and file system layers.
 402  */
 403 static int block_device_ejected(struct super_block *sb)
 404 {
 405         struct inode *bd_inode = sb->s_bdev->bd_inode;
 406         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 407
 408         return bdi->dev == NULL;
 409 }
 410
 411 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 412 {
 413         struct super_block              *sb = journal->j_private;
 414         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 415         int                             error = is_journal_aborted(journal);
 416         struct ext4_journal_cb_entry    *jce;
 417
 418         BUG_ON(txn->t_state == T_FINISHED);
 419
 420         ext4_process_freed_data(sb, txn->t_tid);
 421
 422         spin_lock(&sbi->s_md_lock);
 423         while (!list_empty(&txn->t_private_list)) {
 424                 jce = list_entry(txn->t_private_list.next,
 425                                  struct ext4_journal_cb_entry, jce_list);
 426                 list_del_init(&jce->jce_list);
 427                 spin_unlock(&sbi->s_md_lock);
 428                 jce->jce_func(sb, jce, error);
 429                 spin_lock(&sbi->s_md_lock);
 430         }
 431         spin_unlock(&sbi->s_md_lock);
 432 }
 433
 434 static bool system_going_down(void)
 435 {
 436         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
 437                 || system_state == SYSTEM_RESTART;
 438 }
 439
 440 /* Deal with the reporting of failure conditions on a filesystem such as
 441  * inconsistencies detected or read IO failures.
 442  *
 443  * On ext2, we can store the error state of the filesystem in the
 444  * superblock.  That is not possible on ext4, because we may have other
 445  * write ordering constraints on the superblock which prevent us from
 446  * writing it out straight away; and given that the journal is about to
 447  * be aborted, we can't rely on the current, or future, transactions to
 448  * write out the superblock safely.
 449  *
 450  * We'll just use the jbd2_journal_abort() error code to record an error in
 451  * the journal instead.  On recovery, the journal will complain about
 452  * that error until we've noted it down and cleared it.
 453  */
 454
 455 static void ext4_handle_error(struct super_block *sb)
 456 {
 457         journal_t *journal = EXT4_SB(sb)->s_journal;
 458
 459         if (test_opt(sb, WARN_ON_ERROR))
 460                 WARN_ON_ONCE(1);
 461
 462         if (sb_rdonly(sb) || test_opt(sb, ERRORS_CONT))
 463                 return;
 464
 465         EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 466         if (journal)
 467                 jbd2_journal_abort(journal, -EIO);
 468         /*
 469          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
 470          * could panic during 'reboot -f' as the underlying device got already
 471          * disabled.
 472          */
 473         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
 474                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 475                 /*
 476                  * Make sure updated value of ->s_mount_flags will be visible
 477                  * before ->s_flags update
 478                  */
 479                 smp_wmb();
 480                 sb->s_flags |= SB_RDONLY;
 481         } else if (test_opt(sb, ERRORS_PANIC)) {
 482                 if (EXT4_SB(sb)->s_journal &&
 483                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 484                         return;
 485                 panic("EXT4-fs (device %s): panic forced after error\n",
 486                         sb->s_id);
 487         }
 488 }
 489
 490 #define ext4_error_ratelimit(sb)                                        \
 491                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 492                              "EXT4-fs error")
 493
 494 void __ext4_error(struct super_block *sb, const char *function,
 495                   unsigned int line, const char *fmt, ...)
 496 {
 497         struct va_format vaf;
 498         va_list args;
 499
 500         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 501                 return;
 502
 503         trace_ext4_error(sb, function, line);
 504         if (ext4_error_ratelimit(sb)) {
 505                 va_start(args, fmt);
 506                 vaf.fmt = fmt;
 507                 vaf.va = &args;
 508                 printk(KERN_CRIT
 509                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 510                        sb->s_id, function, line, current->comm, &vaf);
 511                 va_end(args);
 512         }
 513         save_error_info(sb, function, line);
 514         ext4_handle_error(sb);
 515 }
 516
 517 void __ext4_error_inode(struct inode *inode, const char *function,
 518                         unsigned int line, ext4_fsblk_t block,
 519                         const char *fmt, ...)
 520 {
 521         va_list args;
 522         struct va_format vaf;
 523         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 524
 525         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 526                 return;
 527
 528         trace_ext4_error(inode->i_sb, function, line);
 529         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 530         es->s_last_error_block = cpu_to_le64(block);
 531         if (ext4_error_ratelimit(inode->i_sb)) {
 532                 va_start(args, fmt);
 533                 vaf.fmt = fmt;
 534                 vaf.va = &args;
 535                 if (block)
 536                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 537                                "inode #%lu: block %llu: comm %s: %pV\n",
 538                                inode->i_sb->s_id, function, line, inode->i_ino,
 539                                block, current->comm, &vaf);
 540                 else
 541                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 542                                "inode #%lu: comm %s: %pV\n",
 543                                inode->i_sb->s_id, function, line, inode->i_ino,
 544                                current->comm, &vaf);
 545                 va_end(args);
 546         }
 547         save_error_info(inode->i_sb, function, line);
 548         ext4_handle_error(inode->i_sb);
 549 }
 550
 551 void __ext4_error_file(struct file *file, const char *function,
 552                        unsigned int line, ext4_fsblk_t block,
 553                        const char *fmt, ...)
 554 {
 555         va_list args;
 556         struct va_format vaf;
 557         struct ext4_super_block *es;
 558         struct inode *inode = file_inode(file);
 559         char pathname[80], *path;
 560
 561         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 562                 return;
 563
 564         trace_ext4_error(inode->i_sb, function, line);
 565         es = EXT4_SB(inode->i_sb)->s_es;
 566         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 567         if (ext4_error_ratelimit(inode->i_sb)) {
 568                 path = file_path(file, pathname, sizeof(pathname));
 569                 if (IS_ERR(path))
 570                         path = "(unknown)";
 571                 va_start(args, fmt);
 572                 vaf.fmt = fmt;
 573                 vaf.va = &args;
 574                 if (block)
 575                         printk(KERN_CRIT
 576                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 577                                "block %llu: comm %s: path %s: %pV\n",
 578                                inode->i_sb->s_id, function, line, inode->i_ino,
 579                                block, current->comm, path, &vaf);
 580                 else
 581                         printk(KERN_CRIT
 582                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 583                                "comm %s: path %s: %pV\n",
 584                                inode->i_sb->s_id, function, line, inode->i_ino,
 585                                current->comm, path, &vaf);
 586                 va_end(args);
 587         }
 588         save_error_info(inode->i_sb, function, line);
 589         ext4_handle_error(inode->i_sb);
 590 }
 591
 592 const char *ext4_decode_error(struct super_block *sb, int errno,
 593                               char nbuf[16])
 594 {
 595         char *errstr = NULL;
 596
 597         switch (errno) {
 598         case -EFSCORRUPTED:
 599                 errstr = "Corrupt filesystem";
 600                 break;
 601         case -EFSBADCRC:
 602                 errstr = "Filesystem failed CRC";
 603                 break;
 604         case -EIO:
 605                 errstr = "IO failure";
 606                 break;
 607         case -ENOMEM:
 608                 errstr = "Out of memory";
 609                 break;
 610         case -EROFS:
 611                 if (!sb || (EXT4_SB(sb)->s_journal &&
 612                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 613                         errstr = "Journal has aborted";
 614                 else
 615                         errstr = "Readonly filesystem";
 616                 break;
 617         default:
 618                 /* If the caller passed in an extra buffer for unknown
 619                  * errors, textualise them now.  Else we just return
 620                  * NULL. */
 621                 if (nbuf) {
 622                         /* Check for truncated error codes... */
 623                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 624                                 errstr = nbuf;
 625                 }
 626                 break;
 627         }
 628
 629         return errstr;
 630 }
 631
 632 /* __ext4_std_error decodes expected errors from journaling functions
 633  * automatically and invokes the appropriate error response.  */
 634
 635 void __ext4_std_error(struct super_block *sb, const char *function,
 636                       unsigned int line, int errno)
 637 {
 638         char nbuf[16];
 639         const char *errstr;
 640
 641         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 642                 return;
 643
 644         /* Special case: if the error is EROFS, and we're not already
 645          * inside a transaction, then there's really no point in logging
 646          * an error. */
 647         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 648                 return;
 649
 650         if (ext4_error_ratelimit(sb)) {
 651                 errstr = ext4_decode_error(sb, errno, nbuf);
 652                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 653                        sb->s_id, function, line, errstr);
 654         }
 655
 656         save_error_info(sb, function, line);
 657         ext4_handle_error(sb);
 658 }
 659
 660 /*
 661  * ext4_abort is a much stronger failure handler than ext4_error.  The
 662  * abort function may be used to deal with unrecoverable failures such
 663  * as journal IO errors or ENOMEM at a critical moment in log management.
 664  *
 665  * We unconditionally force the filesystem into an ABORT|READONLY state,
 666  * unless the error response on the fs has been set to panic in which
 667  * case we take the easy way out and panic immediately.
 668  */
 669
 670 void __ext4_abort(struct super_block *sb, const char *function,
 671                 unsigned int line, const char *fmt, ...)
 672 {
 673         struct va_format vaf;
 674         va_list args;
 675
 676         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 677                 return;
 678
 679         save_error_info(sb, function, line);
 680         va_start(args, fmt);
 681         vaf.fmt = fmt;
 682         vaf.va = &args;
 683         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 684                sb->s_id, function, line, &vaf);
 685         va_end(args);
 686
 687         if (sb_rdonly(sb) == 0) {
 688                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 689                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 690                 /*
 691                  * Make sure updated value of ->s_mount_flags will be visible
 692                  * before ->s_flags update
 693                  */
 694                 smp_wmb();
 695                 sb->s_flags |= SB_RDONLY;
 696                 if (EXT4_SB(sb)->s_journal)
 697                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 698                 save_error_info(sb, function, line);
 699         }
 700         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
 701                 if (EXT4_SB(sb)->s_journal &&
 702                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 703                         return;
 704                 panic("EXT4-fs panic from previous error\n");
 705         }
 706 }
 707
 708 void __ext4_msg(struct super_block *sb,
 709                 const char *prefix, const char *fmt, ...)
 710 {
 711         struct va_format vaf;
 712         va_list args;
 713
 714         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 715                 return;
 716
 717         va_start(args, fmt);
 718         vaf.fmt = fmt;
 719         vaf.va = &args;
 720         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 721         va_end(args);
 722 }
 723
 724 #define ext4_warning_ratelimit(sb)                                      \
 725                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 726                              "EXT4-fs warning")
 727
 728 void __ext4_warning(struct super_block *sb, const char *function,
 729                     unsigned int line, const char *fmt, ...)
 730 {
 731         struct va_format vaf;
 732         va_list args;
 733
 734         if (!ext4_warning_ratelimit(sb))
 735                 return;
 736
 737         va_start(args, fmt);
 738         vaf.fmt = fmt;
 739         vaf.va = &args;
 740         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 741                sb->s_id, function, line, &vaf);
 742         va_end(args);
 743 }
 744
 745 void __ext4_warning_inode(const struct inode *inode, const char *function,
 746                           unsigned int line, const char *fmt, ...)
 747 {
 748         struct va_format vaf;
 749         va_list args;
 750
 751         if (!ext4_warning_ratelimit(inode->i_sb))
 752                 return;
 753
 754         va_start(args, fmt);
 755         vaf.fmt = fmt;
 756         vaf.va = &args;
 757         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 758                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 759                function, line, inode->i_ino, current->comm, &vaf);
 760         va_end(args);
 761 }
 762
 763 void __ext4_grp_locked_error(const char *function, unsigned int line,
 764                              struct super_block *sb, ext4_group_t grp,
 765                              unsigned long ino, ext4_fsblk_t block,
 766                              const char *fmt, ...)
 767 __releases(bitlock)
 768 __acquires(bitlock)
 769 {
 770         struct va_format vaf;
 771         va_list args;
 772         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 773
 774         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 775                 return;
 776
 777         trace_ext4_error(sb, function, line);
 778         es->s_last_error_ino = cpu_to_le32(ino);
 779         es->s_last_error_block = cpu_to_le64(block);
 780         __save_error_info(sb, function, line);
 781
 782         if (ext4_error_ratelimit(sb)) {
 783                 va_start(args, fmt);
 784                 vaf.fmt = fmt;
 785                 vaf.va = &args;
 786                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 787                        sb->s_id, function, line, grp);
 788                 if (ino)
 789                         printk(KERN_CONT "inode %lu: ", ino);
 790                 if (block)
 791                         printk(KERN_CONT "block %llu:",
 792                                (unsigned long long) block);
 793                 printk(KERN_CONT "%pV\n", &vaf);
 794                 va_end(args);
 795         }
 796
 797         if (test_opt(sb, WARN_ON_ERROR))
 798                 WARN_ON_ONCE(1);
 799
 800         if (test_opt(sb, ERRORS_CONT)) {
 801                 ext4_commit_super(sb, 0);
 802                 return;
 803         }
 804
 805         ext4_unlock_group(sb, grp);
 806         ext4_commit_super(sb, 1);
 807         ext4_handle_error(sb);
 808         /*
 809          * We only get here in the ERRORS_RO case; relocking the group
 810          * may be dangerous, but nothing bad will happen since the
 811          * filesystem will have already been marked read/only and the
 812          * journal has been aborted.  We return 1 as a hint to callers
 813          * who might what to use the return value from
 814          * ext4_grp_locked_error() to distinguish between the
 815          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 816          * aggressively from the ext4 function in question, with a
 817          * more appropriate error code.
 818          */
 819         ext4_lock_group(sb, grp);
 820         return;
 821 }
 822
 823 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
 824                                      ext4_group_t group,
 825                                      unsigned int flags)
 826 {
 827         struct ext4_sb_info *sbi = EXT4_SB(sb);
 828         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 829         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
 830         int ret;
 831
 832         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
 833                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
 834                                             &grp->bb_state);
 835                 if (!ret)
 836                         percpu_counter_sub(&sbi->s_freeclusters_counter,
 837                                            grp->bb_free);
 838         }
 839
 840         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
 841                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
 842                                             &grp->bb_state);
 843                 if (!ret && gdp) {
 844                         int count;
 845
 846                         count = ext4_free_inodes_count(sb, gdp);
 847                         percpu_counter_sub(&sbi->s_freeinodes_counter,
 848                                            count);
 849                 }
 850         }
 851 }
 852
 853 void ext4_update_dynamic_rev(struct super_block *sb)
 854 {
 855         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 856
 857         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 858                 return;
 859
 860         ext4_warning(sb,
 861                      "updating to rev %d because of new feature flag, "
 862                      "running e2fsck is recommended",
 863                      EXT4_DYNAMIC_REV);
 864
 865         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 866         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 867         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 868         /* leave es->s_feature_*compat flags alone */
 869         /* es->s_uuid will be set by e2fsck if empty */
 870
 871         /*
 872          * The rest of the superblock fields should be zero, and if not it
 873          * means they are likely already in use, so leave them alone.  We
 874          * can leave it up to e2fsck to clean up any inconsistencies there.
 875          */
 876 }
 877
 878 /*
 879  * Open the external journal device
 880  */
 881 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 882 {
 883         struct block_device *bdev;
 884         char b[BDEVNAME_SIZE];
 885
 886         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 887         if (IS_ERR(bdev))
 888                 goto fail;
 889         return bdev;
 890
 891 fail:
 892         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 893                         __bdevname(dev, b), PTR_ERR(bdev));
 894         return NULL;
 895 }
 896
 897 /*
 898  * Release the journal device
 899  */
 900 static void ext4_blkdev_put(struct block_device *bdev)
 901 {
 902         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 903 }
 904
 905 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 906 {
 907         struct block_device *bdev;
 908         bdev = sbi->journal_bdev;
 909         if (bdev) {
 910                 ext4_blkdev_put(bdev);
 911                 sbi->journal_bdev = NULL;
 912         }
 913 }
 914
 915 static inline struct inode *orphan_list_entry(struct list_head *l)
 916 {
 917         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 918 }
 919
 920 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 921 {
 922         struct list_head *l;
 923
 924         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 925                  le32_to_cpu(sbi->s_es->s_last_orphan));
 926
 927         printk(KERN_ERR "sb_info orphan list:\n");
 928         list_for_each(l, &sbi->s_orphan) {
 929                 struct inode *inode = orphan_list_entry(l);
 930                 printk(KERN_ERR "  "
 931                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 932                        inode->i_sb->s_id, inode->i_ino, inode,
 933                        inode->i_mode, inode->i_nlink,
 934                        NEXT_ORPHAN(inode));
 935         }
 936 }
 937
 938 #ifdef CONFIG_QUOTA
 939 static int ext4_quota_off(struct super_block *sb, int type);
 940
 941 static inline void ext4_quota_off_umount(struct super_block *sb)
 942 {
 943         int type;
 944
 945         /* Use our quota_off function to clear inode flags etc. */
 946         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 947                 ext4_quota_off(sb, type);
 948 }
 949
 950 /*
 951  * This is a helper function which is used in the mount/remount
 952  * codepaths (which holds s_umount) to fetch the quota file name.
 953  */
 954 static inline char *get_qf_name(struct super_block *sb,
 955                                 struct ext4_sb_info *sbi,
 956                                 int type)
 957 {
 958         return rcu_dereference_protected(sbi->s_qf_names[type],
 959                                          lockdep_is_held(&sb->s_umount));
 960 }
 961 #else
 962 static inline void ext4_quota_off_umount(struct super_block *sb)
 963 {
 964 }
 965 #endif
 966
 967 static void ext4_put_super(struct super_block *sb)
 968 {
 969         struct ext4_sb_info *sbi = EXT4_SB(sb);
 970         struct ext4_super_block *es = sbi->s_es;
 971         struct buffer_head **group_desc;
 972         struct flex_groups **flex_groups;
 973         int aborted = 0;
 974         int i, err;
 975
 976         ext4_unregister_li_request(sb);
 977         ext4_quota_off_umount(sb);
 978
 979         destroy_workqueue(sbi->rsv_conversion_wq);
 980
 981         if (sbi->s_journal) {
 982                 aborted = is_journal_aborted(sbi->s_journal);
 983                 err = jbd2_journal_destroy(sbi->s_journal);
 984                 sbi->s_journal = NULL;
 985                 if ((err < 0) && !aborted)
 986                         ext4_abort(sb, "Couldn't clean up the journal");
 987         }
 988
 989         ext4_unregister_sysfs(sb);
 990         ext4_es_unregister_shrinker(sbi);
 991         del_timer_sync(&sbi->s_err_report);
 992         ext4_release_system_zone(sb);
 993         ext4_mb_release(sb);
 994         ext4_ext_release(sb);
 995
 996         if (!sb_rdonly(sb) && !aborted) {
 997                 ext4_clear_feature_journal_needs_recovery(sb);
 998                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 999         }
1000         if (!sb_rdonly(sb))
1001                 ext4_commit_super(sb, 1);
1002
1003         rcu_read_lock();
1004         group_desc = rcu_dereference(sbi->s_group_desc);
1005         for (i = 0; i < sbi->s_gdb_count; i++)
1006                 brelse(group_desc[i]);
1007         kvfree(group_desc);
1008         flex_groups = rcu_dereference(sbi->s_flex_groups);
1009         if (flex_groups) {
1010                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1011                         kvfree(flex_groups[i]);
1012                 kvfree(flex_groups);
1013         }
1014         rcu_read_unlock();
1015         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1016         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1017         percpu_counter_destroy(&sbi->s_dirs_counter);
1018         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1019         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1020 #ifdef CONFIG_QUOTA
1021         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1022                 kfree(get_qf_name(sb, sbi, i));
1023 #endif
1024
1025         /* Debugging code just in case the in-memory inode orphan list
1026          * isn't empty.  The on-disk one can be non-empty if we've
1027          * detected an error and taken the fs readonly, but the
1028          * in-memory list had better be clean by this point. */
1029         if (!list_empty(&sbi->s_orphan))
1030                 dump_orphan_list(sb, sbi);
1031         J_ASSERT(list_empty(&sbi->s_orphan));
1032
1033         sync_blockdev(sb->s_bdev);
1034         invalidate_bdev(sb->s_bdev);
1035         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1036                 /*
1037                  * Invalidate the journal device's buffers.  We don't want them
1038                  * floating about in memory - the physical journal device may
1039                  * hotswapped, and it breaks the `ro-after' testing code.
1040                  */
1041                 sync_blockdev(sbi->journal_bdev);
1042                 invalidate_bdev(sbi->journal_bdev);
1043                 ext4_blkdev_remove(sbi);
1044         }
1045         if (sbi->s_ea_inode_cache) {
1046                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1047                 sbi->s_ea_inode_cache = NULL;
1048         }
1049         if (sbi->s_ea_block_cache) {
1050                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1051                 sbi->s_ea_block_cache = NULL;
1052         }
1053         if (sbi->s_mmp_tsk)
1054                 kthread_stop(sbi->s_mmp_tsk);
1055         brelse(sbi->s_sbh);
1056         sb->s_fs_info = NULL;
1057         /*
1058          * Now that we are completely done shutting down the
1059          * superblock, we need to actually destroy the kobject.
1060          */
1061         kobject_put(&sbi->s_kobj);
1062         wait_for_completion(&sbi->s_kobj_unregister);
1063         if (sbi->s_chksum_driver)
1064                 crypto_free_shash(sbi->s_chksum_driver);
1065         kfree(sbi->s_blockgroup_lock);
1066         fs_put_dax(sbi->s_daxdev);
1067         kfree(sbi);
1068 }
1069
1070 static struct kmem_cache *ext4_inode_cachep;
1071
1072 /*
1073  * Called inside transaction, so use GFP_NOFS
1074  */
1075 static struct inode *ext4_alloc_inode(struct super_block *sb)
1076 {
1077         struct ext4_inode_info *ei;
1078
1079         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1080         if (!ei)
1081                 return NULL;
1082
1083         inode_set_iversion(&ei->vfs_inode, 1);
1084         ei->i_flags = 0;
1085         spin_lock_init(&ei->i_raw_lock);
1086         INIT_LIST_HEAD(&ei->i_prealloc_list);
1087         spin_lock_init(&ei->i_prealloc_lock);
1088         ext4_es_init_tree(&ei->i_es_tree);
1089         rwlock_init(&ei->i_es_lock);
1090         INIT_LIST_HEAD(&ei->i_es_list);
1091         ei->i_es_all_nr = 0;
1092         ei->i_es_shk_nr = 0;
1093         ei->i_es_shrink_lblk = 0;
1094         ei->i_reserved_data_blocks = 0;
1095         ei->i_da_metadata_calc_len = 0;
1096         ei->i_da_metadata_calc_last_lblock = 0;
1097         spin_lock_init(&(ei->i_block_reservation_lock));
1098 #ifdef CONFIG_QUOTA
1099         ei->i_reserved_quota = 0;
1100         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1101 #endif
1102         ei->jinode = NULL;
1103         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1104         spin_lock_init(&ei->i_completed_io_lock);
1105         ei->i_sync_tid = 0;
1106         ei->i_datasync_tid = 0;
1107         atomic_set(&ei->i_unwritten, 0);
1108         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1109         return &ei->vfs_inode;
1110 }
1111
1112 static int ext4_drop_inode(struct inode *inode)
1113 {
1114         int drop = generic_drop_inode(inode);
1115
1116         trace_ext4_drop_inode(inode, drop);
1117         return drop;
1118 }
1119
1120 static void ext4_i_callback(struct rcu_head *head)
1121 {
1122         struct inode *inode = container_of(head, struct inode, i_rcu);
1123         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1124 }
1125
1126 static void ext4_destroy_inode(struct inode *inode)
1127 {
1128         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1129                 ext4_msg(inode->i_sb, KERN_ERR,
1130                          "Inode %lu (%p): orphan list check failed!",
1131                          inode->i_ino, EXT4_I(inode));
1132                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1133                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1134                                 true);
1135                 dump_stack();
1136         }
1137         call_rcu(&inode->i_rcu, ext4_i_callback);
1138 }
1139
1140 static void init_once(void *foo)
1141 {
1142         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1143
1144         INIT_LIST_HEAD(&ei->i_orphan);
1145         init_rwsem(&ei->xattr_sem);
1146         init_rwsem(&ei->i_data_sem);
1147         init_rwsem(&ei->i_mmap_sem);
1148         inode_init_once(&ei->vfs_inode);
1149 }
1150
1151 static int __init init_inodecache(void)
1152 {
1153         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1154                                 sizeof(struct ext4_inode_info), 0,
1155                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1156                                         SLAB_ACCOUNT),
1157                                 offsetof(struct ext4_inode_info, i_data),
1158                                 sizeof_field(struct ext4_inode_info, i_data),
1159                                 init_once);
1160         if (ext4_inode_cachep == NULL)
1161                 return -ENOMEM;
1162         return 0;
1163 }
1164
1165 static void destroy_inodecache(void)
1166 {
1167         /*
1168          * Make sure all delayed rcu free inodes are flushed before we
1169          * destroy cache.
1170          */
1171         rcu_barrier();
1172         kmem_cache_destroy(ext4_inode_cachep);
1173 }
1174
1175 void ext4_clear_inode(struct inode *inode)
1176 {
1177         invalidate_inode_buffers(inode);
1178         clear_inode(inode);
1179         dquot_drop(inode);
1180         ext4_discard_preallocations(inode);
1181         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1182         if (EXT4_I(inode)->jinode) {
1183                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1184                                                EXT4_I(inode)->jinode);
1185                 jbd2_free_inode(EXT4_I(inode)->jinode);
1186                 EXT4_I(inode)->jinode = NULL;
1187         }
1188         fscrypt_put_encryption_info(inode);
1189 }
1190
1191 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1192                                         u64 ino, u32 generation)
1193 {
1194         struct inode *inode;
1195
1196         /*
1197          * Currently we don't know the generation for parent directory, so
1198          * a generation of 0 means "accept any"
1199          */
1200         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1201         if (IS_ERR(inode))
1202                 return ERR_CAST(inode);
1203         if (generation && inode->i_generation != generation) {
1204                 iput(inode);
1205                 return ERR_PTR(-ESTALE);
1206         }
1207
1208         return inode;
1209 }
1210
1211 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1212                                         int fh_len, int fh_type)
1213 {
1214         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1215                                     ext4_nfs_get_inode);
1216 }
1217
1218 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1219                                         int fh_len, int fh_type)
1220 {
1221         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1222                                     ext4_nfs_get_inode);
1223 }
1224
1225 static int ext4_nfs_commit_metadata(struct inode *inode)
1226 {
1227         struct writeback_control wbc = {
1228                 .sync_mode = WB_SYNC_ALL
1229         };
1230
1231         trace_ext4_nfs_commit_metadata(inode);
1232         return ext4_write_inode(inode, &wbc);
1233 }
1234
1235 /*
1236  * Try to release metadata pages (indirect blocks, directories) which are
1237  * mapped via the block device.  Since these pages could have journal heads
1238  * which would prevent try_to_free_buffers() from freeing them, we must use
1239  * jbd2 layer's try_to_free_buffers() function to release them.
1240  */
1241 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1242                                  gfp_t wait)
1243 {
1244         journal_t *journal = EXT4_SB(sb)->s_journal;
1245
1246         WARN_ON(PageChecked(page));
1247         if (!page_has_buffers(page))
1248                 return 0;
1249         if (journal)
1250                 return jbd2_journal_try_to_free_buffers(journal, page,
1251                                                 wait & ~__GFP_DIRECT_RECLAIM);
1252         return try_to_free_buffers(page);
1253 }
1254
1255 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1256 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1257 {
1258         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1259                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1260 }
1261
1262 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1263                                                         void *fs_data)
1264 {
1265         handle_t *handle = fs_data;
1266         int res, res2, credits, retries = 0;
1267
1268         /*
1269          * Encrypting the root directory is not allowed because e2fsck expects
1270          * lost+found to exist and be unencrypted, and encrypting the root
1271          * directory would imply encrypting the lost+found directory as well as
1272          * the filename "lost+found" itself.
1273          */
1274         if (inode->i_ino == EXT4_ROOT_INO)
1275                 return -EPERM;
1276
1277         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1278                 return -EINVAL;
1279
1280         res = ext4_convert_inline_data(inode);
1281         if (res)
1282                 return res;
1283
1284         /*
1285          * If a journal handle was specified, then the encryption context is
1286          * being set on a new inode via inheritance and is part of a larger
1287          * transaction to create the inode.  Otherwise the encryption context is
1288          * being set on an existing inode in its own transaction.  Only in the
1289          * latter case should the "retry on ENOSPC" logic be used.
1290          */
1291
1292         if (handle) {
1293                 res = ext4_xattr_set_handle(handle, inode,
1294                                             EXT4_XATTR_INDEX_ENCRYPTION,
1295                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1296                                             ctx, len, 0);
1297                 if (!res) {
1298                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1299                         ext4_clear_inode_state(inode,
1300                                         EXT4_STATE_MAY_INLINE_DATA);
1301                         /*
1302                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1303                          * S_DAX may be disabled
1304                          */
1305                         ext4_set_inode_flags(inode);
1306                 }
1307                 return res;
1308         }
1309
1310         res = dquot_initialize(inode);
1311         if (res)
1312                 return res;
1313 retry:
1314         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1315                                      &credits);
1316         if (res)
1317                 return res;
1318
1319         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1320         if (IS_ERR(handle))
1321                 return PTR_ERR(handle);
1322
1323         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1324                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1325                                     ctx, len, 0);
1326         if (!res) {
1327                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1328                 /*
1329                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1330                  * S_DAX may be disabled
1331                  */
1332                 ext4_set_inode_flags(inode);
1333                 res = ext4_mark_inode_dirty(handle, inode);
1334                 if (res)
1335                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1336         }
1337         res2 = ext4_journal_stop(handle);
1338
1339         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1340                 goto retry;
1341         if (!res)
1342                 res = res2;
1343         return res;
1344 }
1345
1346 static bool ext4_dummy_context(struct inode *inode)
1347 {
1348         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1349 }
1350
1351 static const struct fscrypt_operations ext4_cryptops = {
1352         .key_prefix             = "ext4:",
1353         .get_context            = ext4_get_context,
1354         .set_context            = ext4_set_context,
1355         .dummy_context          = ext4_dummy_context,
1356         .empty_dir              = ext4_empty_dir,
1357         .max_namelen            = EXT4_NAME_LEN,
1358 };
1359 #endif
1360
1361 #ifdef CONFIG_QUOTA
1362 static const char * const quotatypes[] = INITQFNAMES;
1363 #define QTYPE2NAME(t) (quotatypes[t])
1364
1365 static int ext4_write_dquot(struct dquot *dquot);
1366 static int ext4_acquire_dquot(struct dquot *dquot);
1367 static int ext4_release_dquot(struct dquot *dquot);
1368 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1369 static int ext4_write_info(struct super_block *sb, int type);
1370 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1371                          const struct path *path);
1372 static int ext4_quota_on_mount(struct super_block *sb, int type);
1373 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1374                                size_t len, loff_t off);
1375 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1376                                 const char *data, size_t len, loff_t off);
1377 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1378                              unsigned int flags);
1379 static int ext4_enable_quotas(struct super_block *sb);
1380 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1381
1382 static struct dquot **ext4_get_dquots(struct inode *inode)
1383 {
1384         return EXT4_I(inode)->i_dquot;
1385 }
1386
1387 static const struct dquot_operations ext4_quota_operations = {
1388         .get_reserved_space     = ext4_get_reserved_space,
1389         .write_dquot            = ext4_write_dquot,
1390         .acquire_dquot          = ext4_acquire_dquot,
1391         .release_dquot          = ext4_release_dquot,
1392         .mark_dirty             = ext4_mark_dquot_dirty,
1393         .write_info             = ext4_write_info,
1394         .alloc_dquot            = dquot_alloc,
1395         .destroy_dquot          = dquot_destroy,
1396         .get_projid             = ext4_get_projid,
1397         .get_inode_usage        = ext4_get_inode_usage,
1398         .get_next_id            = ext4_get_next_id,
1399 };
1400
1401 static const struct quotactl_ops ext4_qctl_operations = {
1402         .quota_on       = ext4_quota_on,
1403         .quota_off      = ext4_quota_off,
1404         .quota_sync     = dquot_quota_sync,
1405         .get_state      = dquot_get_state,
1406         .set_info       = dquot_set_dqinfo,
1407         .get_dqblk      = dquot_get_dqblk,
1408         .set_dqblk      = dquot_set_dqblk,
1409         .get_nextdqblk  = dquot_get_next_dqblk,
1410 };
1411 #endif
1412
1413 static const struct super_operations ext4_sops = {
1414         .alloc_inode    = ext4_alloc_inode,
1415         .destroy_inode  = ext4_destroy_inode,
1416         .write_inode    = ext4_write_inode,
1417         .dirty_inode    = ext4_dirty_inode,
1418         .drop_inode     = ext4_drop_inode,
1419         .evict_inode    = ext4_evict_inode,
1420         .put_super      = ext4_put_super,
1421         .sync_fs        = ext4_sync_fs,
1422         .freeze_fs      = ext4_freeze,
1423         .unfreeze_fs    = ext4_unfreeze,
1424         .statfs         = ext4_statfs,
1425         .remount_fs     = ext4_remount,
1426         .show_options   = ext4_show_options,
1427 #ifdef CONFIG_QUOTA
1428         .quota_read     = ext4_quota_read,
1429         .quota_write    = ext4_quota_write,
1430         .get_dquots     = ext4_get_dquots,
1431 #endif
1432         .bdev_try_to_free_page = bdev_try_to_free_page,
1433 };
1434
1435 static const struct export_operations ext4_export_ops = {
1436         .fh_to_dentry = ext4_fh_to_dentry,
1437         .fh_to_parent = ext4_fh_to_parent,
1438         .get_parent = ext4_get_parent,
1439         .commit_metadata = ext4_nfs_commit_metadata,
1440 };
1441
1442 enum {
1443         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1444         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1445         Opt_nouid32, Opt_debug, Opt_removed,
1446         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1447         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1448         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1449         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1450         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1451         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1452         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1453         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1454         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1455         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1456         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1457         Opt_nowarn_on_error, Opt_mblk_io_submit,
1458         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1459         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1460         Opt_inode_readahead_blks, Opt_journal_ioprio,
1461         Opt_dioread_nolock, Opt_dioread_lock,
1462         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1463         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1464 };
1465
1466 static const match_table_t tokens = {
1467         {Opt_bsd_df, "bsddf"},
1468         {Opt_minix_df, "minixdf"},
1469         {Opt_grpid, "grpid"},
1470         {Opt_grpid, "bsdgroups"},
1471         {Opt_nogrpid, "nogrpid"},
1472         {Opt_nogrpid, "sysvgroups"},
1473         {Opt_resgid, "resgid=%u"},
1474         {Opt_resuid, "resuid=%u"},
1475         {Opt_sb, "sb=%u"},
1476         {Opt_err_cont, "errors=continue"},
1477         {Opt_err_panic, "errors=panic"},
1478         {Opt_err_ro, "errors=remount-ro"},
1479         {Opt_nouid32, "nouid32"},
1480         {Opt_debug, "debug"},
1481         {Opt_removed, "oldalloc"},
1482         {Opt_removed, "orlov"},
1483         {Opt_user_xattr, "user_xattr"},
1484         {Opt_nouser_xattr, "nouser_xattr"},
1485         {Opt_acl, "acl"},
1486         {Opt_noacl, "noacl"},
1487         {Opt_noload, "norecovery"},
1488         {Opt_noload, "noload"},
1489         {Opt_removed, "nobh"},
1490         {Opt_removed, "bh"},
1491         {Opt_commit, "commit=%u"},
1492         {Opt_min_batch_time, "min_batch_time=%u"},
1493         {Opt_max_batch_time, "max_batch_time=%u"},
1494         {Opt_journal_dev, "journal_dev=%u"},
1495         {Opt_journal_path, "journal_path=%s"},
1496         {Opt_journal_checksum, "journal_checksum"},
1497         {Opt_nojournal_checksum, "nojournal_checksum"},
1498         {Opt_journal_async_commit, "journal_async_commit"},
1499         {Opt_abort, "abort"},
1500         {Opt_data_journal, "data=journal"},
1501         {Opt_data_ordered, "data=ordered"},
1502         {Opt_data_writeback, "data=writeback"},
1503         {Opt_data_err_abort, "data_err=abort"},
1504         {Opt_data_err_ignore, "data_err=ignore"},
1505         {Opt_offusrjquota, "usrjquota="},
1506         {Opt_usrjquota, "usrjquota=%s"},
1507         {Opt_offgrpjquota, "grpjquota="},
1508         {Opt_grpjquota, "grpjquota=%s"},
1509         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1510         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1511         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1512         {Opt_grpquota, "grpquota"},
1513         {Opt_noquota, "noquota"},
1514         {Opt_quota, "quota"},
1515         {Opt_usrquota, "usrquota"},
1516         {Opt_prjquota, "prjquota"},
1517         {Opt_barrier, "barrier=%u"},
1518         {Opt_barrier, "barrier"},
1519         {Opt_nobarrier, "nobarrier"},
1520         {Opt_i_version, "i_version"},
1521         {Opt_dax, "dax"},
1522         {Opt_stripe, "stripe=%u"},
1523         {Opt_delalloc, "delalloc"},
1524         {Opt_warn_on_error, "warn_on_error"},
1525         {Opt_nowarn_on_error, "nowarn_on_error"},
1526         {Opt_lazytime, "lazytime"},
1527         {Opt_nolazytime, "nolazytime"},
1528         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1529         {Opt_nodelalloc, "nodelalloc"},
1530         {Opt_removed, "mblk_io_submit"},
1531         {Opt_removed, "nomblk_io_submit"},
1532         {Opt_block_validity, "block_validity"},
1533         {Opt_noblock_validity, "noblock_validity"},
1534         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1535         {Opt_journal_ioprio, "journal_ioprio=%u"},
1536         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1537         {Opt_auto_da_alloc, "auto_da_alloc"},
1538         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1539         {Opt_dioread_nolock, "dioread_nolock"},
1540         {Opt_dioread_lock, "dioread_lock"},
1541         {Opt_discard, "discard"},
1542         {Opt_nodiscard, "nodiscard"},
1543         {Opt_init_itable, "init_itable=%u"},
1544         {Opt_init_itable, "init_itable"},
1545         {Opt_noinit_itable, "noinit_itable"},
1546         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1547         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1548         {Opt_nombcache, "nombcache"},
1549         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1550         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1551         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1552         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1553         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1554         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1555         {Opt_err, NULL},
1556 };
1557
1558 static ext4_fsblk_t get_sb_block(void **data)
1559 {
1560         ext4_fsblk_t    sb_block;
1561         char            *options = (char *) *data;
1562
1563         if (!options || strncmp(options, "sb=", 3) != 0)
1564                 return 1;       /* Default location */
1565
1566         options += 3;
1567         /* TODO: use simple_strtoll with >32bit ext4 */
1568         sb_block = simple_strtoul(options, &options, 0);
1569         if (*options && *options != ',') {
1570                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1571                        (char *) *data);
1572                 return 1;
1573         }
1574         if (*options == ',')
1575                 options++;
1576         *data = (void *) options;
1577
1578         return sb_block;
1579 }
1580
1581 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1582 static const char deprecated_msg[] =
1583         "Mount option \"%s\" will be removed by %s\n"
1584         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1585
1586 #ifdef CONFIG_QUOTA
1587 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1588 {
1589         struct ext4_sb_info *sbi = EXT4_SB(sb);
1590         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1591         int ret = -1;
1592
1593         if (sb_any_quota_loaded(sb) && !old_qname) {
1594                 ext4_msg(sb, KERN_ERR,
1595                         "Cannot change journaled "
1596                         "quota options when quota turned on");
1597                 return -1;
1598         }
1599         if (ext4_has_feature_quota(sb)) {
1600                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1601                          "ignored when QUOTA feature is enabled");
1602                 return 1;
1603         }
1604         qname = match_strdup(args);
1605         if (!qname) {
1606                 ext4_msg(sb, KERN_ERR,
1607                         "Not enough memory for storing quotafile name");
1608                 return -1;
1609         }
1610         if (old_qname) {
1611                 if (strcmp(old_qname, qname) == 0)
1612                         ret = 1;
1613                 else
1614                         ext4_msg(sb, KERN_ERR,
1615                                  "%s quota file already specified",
1616                                  QTYPE2NAME(qtype));
1617                 goto errout;
1618         }
1619         if (strchr(qname, '/')) {
1620                 ext4_msg(sb, KERN_ERR,
1621                         "quotafile must be on filesystem root");
1622                 goto errout;
1623         }
1624         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1625         set_opt(sb, QUOTA);
1626         return 1;
1627 errout:
1628         kfree(qname);
1629         return ret;
1630 }
1631
1632 static int clear_qf_name(struct super_block *sb, int qtype)
1633 {
1634
1635         struct ext4_sb_info *sbi = EXT4_SB(sb);
1636         char *old_qname = get_qf_name(sb, sbi, qtype);
1637
1638         if (sb_any_quota_loaded(sb) && old_qname) {
1639                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1640                         " when quota turned on");
1641                 return -1;
1642         }
1643         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1644         synchronize_rcu();
1645         kfree(old_qname);
1646         return 1;
1647 }
1648 #endif
1649
1650 #define MOPT_SET        0x0001
1651 #define MOPT_CLEAR      0x0002
1652 #define MOPT_NOSUPPORT  0x0004
1653 #define MOPT_EXPLICIT   0x0008
1654 #define MOPT_CLEAR_ERR  0x0010
1655 #define MOPT_GTE0       0x0020
1656 #ifdef CONFIG_QUOTA
1657 #define MOPT_Q          0
1658 #define MOPT_QFMT       0x0040
1659 #else
1660 #define MOPT_Q          MOPT_NOSUPPORT
1661 #define MOPT_QFMT       MOPT_NOSUPPORT
1662 #endif
1663 #define MOPT_DATAJ      0x0080
1664 #define MOPT_NO_EXT2    0x0100
1665 #define MOPT_NO_EXT3    0x0200
1666 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1667 #define MOPT_STRING     0x0400
1668
1669 static const struct mount_opts {
1670         int     token;
1671         int     mount_opt;
1672         int     flags;
1673 } ext4_mount_opts[] = {
1674         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1675         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1676         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1677         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1678         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1679         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1680         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1681          MOPT_EXT4_ONLY | MOPT_SET},
1682         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1683          MOPT_EXT4_ONLY | MOPT_CLEAR},
1684         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1685         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1686         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1687          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1688         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1689          MOPT_EXT4_ONLY | MOPT_CLEAR},
1690         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1691         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1692         {Opt_commit, 0, MOPT_NO_EXT2},
1693         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1694          MOPT_EXT4_ONLY | MOPT_CLEAR},
1695         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1696          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1697         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1698                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1699          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1700         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1701         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1702         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1703         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1704         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1705          MOPT_NO_EXT2},
1706         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1707          MOPT_NO_EXT2},
1708         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1709         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1710         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1711         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1712         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1713         {Opt_commit, 0, MOPT_GTE0},
1714         {Opt_max_batch_time, 0, MOPT_GTE0},
1715         {Opt_min_batch_time, 0, MOPT_GTE0},
1716         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1717         {Opt_init_itable, 0, MOPT_GTE0},
1718         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1719         {Opt_stripe, 0, MOPT_GTE0},
1720         {Opt_resuid, 0, MOPT_GTE0},
1721         {Opt_resgid, 0, MOPT_GTE0},
1722         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1723         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1724         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1725         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1726         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1727         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1728          MOPT_NO_EXT2 | MOPT_DATAJ},
1729         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1730         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1731 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1732         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1733         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1734 #else
1735         {Opt_acl, 0, MOPT_NOSUPPORT},
1736         {Opt_noacl, 0, MOPT_NOSUPPORT},
1737 #endif
1738         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1739         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1740         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1741         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1742         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1743                                                         MOPT_SET | MOPT_Q},
1744         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1745                                                         MOPT_SET | MOPT_Q},
1746         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1747                                                         MOPT_SET | MOPT_Q},
1748         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1749                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1750                                                         MOPT_CLEAR | MOPT_Q},
1751         {Opt_usrjquota, 0, MOPT_Q | MOPT_STRING},
1752         {Opt_grpjquota, 0, MOPT_Q | MOPT_STRING},
1753         {Opt_offusrjquota, 0, MOPT_Q},
1754         {Opt_offgrpjquota, 0, MOPT_Q},
1755         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1756         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1757         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1758         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1759         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1760         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1761         {Opt_err, 0, 0}
1762 };
1763
1764 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1765                             substring_t *args, unsigned long *journal_devnum,
1766                             unsigned int *journal_ioprio, int is_remount)
1767 {
1768         struct ext4_sb_info *sbi = EXT4_SB(sb);
1769         const struct mount_opts *m;
1770         kuid_t uid;
1771         kgid_t gid;
1772         int arg = 0;
1773
1774 #ifdef CONFIG_QUOTA
1775         if (token == Opt_usrjquota)
1776                 return set_qf_name(sb, USRQUOTA, &args[0]);
1777         else if (token == Opt_grpjquota)
1778                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1779         else if (token == Opt_offusrjquota)
1780                 return clear_qf_name(sb, USRQUOTA);
1781         else if (token == Opt_offgrpjquota)
1782                 return clear_qf_name(sb, GRPQUOTA);
1783 #endif
1784         switch (token) {
1785         case Opt_noacl:
1786         case Opt_nouser_xattr:
1787                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1788                 break;
1789         case Opt_sb:
1790                 return 1;       /* handled by get_sb_block() */
1791         case Opt_removed:
1792                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1793                 return 1;
1794         case Opt_abort:
1795                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1796                 return 1;
1797         case Opt_i_version:
1798                 sb->s_flags |= SB_I_VERSION;
1799                 return 1;
1800         case Opt_lazytime:
1801                 sb->s_flags |= SB_LAZYTIME;
1802                 return 1;
1803         case Opt_nolazytime:
1804                 sb->s_flags &= ~SB_LAZYTIME;
1805                 return 1;
1806         }
1807
1808         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1809                 if (token == m->token)
1810                         break;
1811
1812         if (m->token == Opt_err) {
1813                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1814                          "or missing value", opt);
1815                 return -1;
1816         }
1817
1818         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1819                 ext4_msg(sb, KERN_ERR,
1820                          "Mount option \"%s\" incompatible with ext2", opt);
1821                 return -1;
1822         }
1823         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1824                 ext4_msg(sb, KERN_ERR,
1825                          "Mount option \"%s\" incompatible with ext3", opt);
1826                 return -1;
1827         }
1828
1829         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1830                 return -1;
1831         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1832                 return -1;
1833         if (m->flags & MOPT_EXPLICIT) {
1834                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1835                         set_opt2(sb, EXPLICIT_DELALLOC);
1836                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1837                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1838                 } else
1839                         return -1;
1840         }
1841         if (m->flags & MOPT_CLEAR_ERR)
1842                 clear_opt(sb, ERRORS_MASK);
1843         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1844                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1845                          "options when quota turned on");
1846                 return -1;
1847         }
1848
1849         if (m->flags & MOPT_NOSUPPORT) {
1850                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1851         } else if (token == Opt_commit) {
1852                 if (arg == 0)
1853                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1854                 sbi->s_commit_interval = HZ * arg;
1855         } else if (token == Opt_debug_want_extra_isize) {
1856                 if ((arg & 1) ||
1857                     (arg < 4) ||
1858                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
1859                         ext4_msg(sb, KERN_ERR,
1860                                  "Invalid want_extra_isize %d", arg);
1861                         return -1;
1862                 }
1863                 sbi->s_want_extra_isize = arg;
1864         } else if (token == Opt_max_batch_time) {
1865                 sbi->s_max_batch_time = arg;
1866         } else if (token == Opt_min_batch_time) {
1867                 sbi->s_min_batch_time = arg;
1868         } else if (token == Opt_inode_readahead_blks) {
1869                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1870                         ext4_msg(sb, KERN_ERR,
1871                                  "EXT4-fs: inode_readahead_blks must be "
1872                                  "0 or a power of 2 smaller than 2^31");
1873                         return -1;
1874                 }
1875                 sbi->s_inode_readahead_blks = arg;
1876         } else if (token == Opt_init_itable) {
1877                 set_opt(sb, INIT_INODE_TABLE);
1878                 if (!args->from)
1879                         arg = EXT4_DEF_LI_WAIT_MULT;
1880                 sbi->s_li_wait_mult = arg;
1881         } else if (token == Opt_max_dir_size_kb) {
1882                 sbi->s_max_dir_size_kb = arg;
1883         } else if (token == Opt_stripe) {
1884                 sbi->s_stripe = arg;
1885         } else if (token == Opt_resuid) {
1886                 uid = make_kuid(current_user_ns(), arg);
1887                 if (!uid_valid(uid)) {
1888                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1889                         return -1;
1890                 }
1891                 sbi->s_resuid = uid;
1892         } else if (token == Opt_resgid) {
1893                 gid = make_kgid(current_user_ns(), arg);
1894                 if (!gid_valid(gid)) {
1895                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1896                         return -1;
1897                 }
1898                 sbi->s_resgid = gid;
1899         } else if (token == Opt_journal_dev) {
1900                 if (is_remount) {
1901                         ext4_msg(sb, KERN_ERR,
1902                                  "Cannot specify journal on remount");
1903                         return -1;
1904                 }
1905                 *journal_devnum = arg;
1906         } else if (token == Opt_journal_path) {
1907                 char *journal_path;
1908                 struct inode *journal_inode;
1909                 struct path path;
1910                 int error;
1911
1912                 if (is_remount) {
1913                         ext4_msg(sb, KERN_ERR,
1914                                  "Cannot specify journal on remount");
1915                         return -1;
1916                 }
1917                 journal_path = match_strdup(&args[0]);
1918                 if (!journal_path) {
1919                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1920                                 "journal device string");
1921                         return -1;
1922                 }
1923
1924                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1925                 if (error) {
1926                         ext4_msg(sb, KERN_ERR, "error: could not find "
1927                                 "journal device path: error %d", error);
1928                         kfree(journal_path);
1929                         return -1;
1930                 }
1931
1932                 journal_inode = d_inode(path.dentry);
1933                 if (!S_ISBLK(journal_inode->i_mode)) {
1934                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1935                                 "is not a block device", journal_path);
1936                         path_put(&path);
1937                         kfree(journal_path);
1938                         return -1;
1939                 }
1940
1941                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1942                 path_put(&path);
1943                 kfree(journal_path);
1944         } else if (token == Opt_journal_ioprio) {
1945                 if (arg > 7) {
1946                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1947                                  " (must be 0-7)");
1948                         return -1;
1949                 }
1950                 *journal_ioprio =
1951                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1952         } else if (token == Opt_test_dummy_encryption) {
1953 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1954                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1955                 ext4_msg(sb, KERN_WARNING,
1956                          "Test dummy encryption mode enabled");
1957 #else
1958                 ext4_msg(sb, KERN_WARNING,
1959                          "Test dummy encryption mount option ignored");
1960 #endif
1961         } else if (m->flags & MOPT_DATAJ) {
1962                 if (is_remount) {
1963                         if (!sbi->s_journal)
1964                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1965                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1966                                 ext4_msg(sb, KERN_ERR,
1967                                          "Cannot change data mode on remount");
1968                                 return -1;
1969                         }
1970                 } else {
1971                         clear_opt(sb, DATA_FLAGS);
1972                         sbi->s_mount_opt |= m->mount_opt;
1973                 }
1974 #ifdef CONFIG_QUOTA
1975         } else if (m->flags & MOPT_QFMT) {
1976                 if (sb_any_quota_loaded(sb) &&
1977                     sbi->s_jquota_fmt != m->mount_opt) {
1978                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1979                                  "quota options when quota turned on");
1980                         return -1;
1981                 }
1982                 if (ext4_has_feature_quota(sb)) {
1983                         ext4_msg(sb, KERN_INFO,
1984                                  "Quota format mount options ignored "
1985                                  "when QUOTA feature is enabled");
1986                         return 1;
1987                 }
1988                 sbi->s_jquota_fmt = m->mount_opt;
1989 #endif
1990         } else if (token == Opt_dax) {
1991 #ifdef CONFIG_FS_DAX
1992                 if (is_remount && test_opt(sb, DAX)) {
1993                         ext4_msg(sb, KERN_ERR, "can't mount with "
1994                                 "both data=journal and dax");
1995                         return -1;
1996                 }
1997                 if (is_remount && !(sbi->s_mount_opt & EXT4_MOUNT_DAX)) {
1998                         ext4_msg(sb, KERN_ERR, "can't change "
1999                                         "dax mount option while remounting");
2000                         return -1;
2001                 }
2002                 ext4_msg(sb, KERN_WARNING,
2003                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2004                         sbi->s_mount_opt |= m->mount_opt;
2005 #else
2006                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2007                 return -1;
2008 #endif
2009         } else if (token == Opt_data_err_abort) {
2010                 sbi->s_mount_opt |= m->mount_opt;
2011         } else if (token == Opt_data_err_ignore) {
2012                 sbi->s_mount_opt &= ~m->mount_opt;
2013         } else {
2014                 if (!args->from)
2015                         arg = 1;
2016                 if (m->flags & MOPT_CLEAR)
2017                         arg = !arg;
2018                 else if (unlikely(!(m->flags & MOPT_SET))) {
2019                         ext4_msg(sb, KERN_WARNING,
2020                                  "buggy handling of option %s", opt);
2021                         WARN_ON(1);
2022                         return -1;
2023                 }
2024                 if (arg != 0)
2025                         sbi->s_mount_opt |= m->mount_opt;
2026                 else
2027                         sbi->s_mount_opt &= ~m->mount_opt;
2028         }
2029         return 1;
2030 }
2031
2032 static int parse_options(char *options, struct super_block *sb,
2033                          unsigned long *journal_devnum,
2034                          unsigned int *journal_ioprio,
2035                          int is_remount)
2036 {
2037         struct ext4_sb_info *sbi = EXT4_SB(sb);
2038         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2039         substring_t args[MAX_OPT_ARGS];
2040         int token;
2041
2042         if (!options)
2043                 return 1;
2044
2045         while ((p = strsep(&options, ",")) != NULL) {
2046                 if (!*p)
2047                         continue;
2048                 /*
2049                  * Initialize args struct so we know whether arg was
2050                  * found; some options take optional arguments.
2051                  */
2052                 args[0].to = args[0].from = NULL;
2053                 token = match_token(p, tokens, args);
2054                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2055                                      journal_ioprio, is_remount) < 0)
2056                         return 0;
2057         }
2058 #ifdef CONFIG_QUOTA
2059         /*
2060          * We do the test below only for project quotas. 'usrquota' and
2061          * 'grpquota' mount options are allowed even without quota feature
2062          * to support legacy quotas in quota files.
2063          */
2064         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2065                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2066                          "Cannot enable project quota enforcement.");
2067                 return 0;
2068         }
2069         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2070         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2071         if (usr_qf_name || grp_qf_name) {
2072                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2073                         clear_opt(sb, USRQUOTA);
2074
2075                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2076                         clear_opt(sb, GRPQUOTA);
2077
2078                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2079                         ext4_msg(sb, KERN_ERR, "old and new quota "
2080                                         "format mixing");
2081                         return 0;
2082                 }
2083
2084                 if (!sbi->s_jquota_fmt) {
2085                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2086                                         "not specified");
2087                         return 0;
2088                 }
2089         }
2090 #endif
2091         if (test_opt(sb, DIOREAD_NOLOCK)) {
2092                 int blocksize =
2093                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2094
2095                 if (blocksize < PAGE_SIZE) {
2096                         ext4_msg(sb, KERN_ERR, "can't mount with "
2097                                  "dioread_nolock if block size != PAGE_SIZE");
2098                         return 0;
2099                 }
2100         }
2101         return 1;
2102 }
2103
2104 static inline void ext4_show_quota_options(struct seq_file *seq,
2105                                            struct super_block *sb)
2106 {
2107 #if defined(CONFIG_QUOTA)
2108         struct ext4_sb_info *sbi = EXT4_SB(sb);
2109         char *usr_qf_name, *grp_qf_name;
2110
2111         if (sbi->s_jquota_fmt) {
2112                 char *fmtname = "";
2113
2114                 switch (sbi->s_jquota_fmt) {
2115                 case QFMT_VFS_OLD:
2116                         fmtname = "vfsold";
2117                         break;
2118                 case QFMT_VFS_V0:
2119                         fmtname = "vfsv0";
2120                         break;
2121                 case QFMT_VFS_V1:
2122                         fmtname = "vfsv1";
2123                         break;
2124                 }
2125                 seq_printf(seq, ",jqfmt=%s", fmtname);
2126         }
2127
2128         rcu_read_lock();
2129         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2130         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2131         if (usr_qf_name)
2132                 seq_show_option(seq, "usrjquota", usr_qf_name);
2133         if (grp_qf_name)
2134                 seq_show_option(seq, "grpjquota", grp_qf_name);
2135         rcu_read_unlock();
2136 #endif
2137 }
2138
2139 static const char *token2str(int token)
2140 {
2141         const struct match_token *t;
2142
2143         for (t = tokens; t->token != Opt_err; t++)
2144                 if (t->token == token && !strchr(t->pattern, '='))
2145                         break;
2146         return t->pattern;
2147 }
2148
2149 /*
2150  * Show an option if
2151  *  - it's set to a non-default value OR
2152  *  - if the per-sb default is different from the global default
2153  */
2154 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2155                               int nodefs)
2156 {
2157         struct ext4_sb_info *sbi = EXT4_SB(sb);
2158         struct ext4_super_block *es = sbi->s_es;
2159         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2160         const struct mount_opts *m;
2161         char sep = nodefs ? '\n' : ',';
2162
2163 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2164 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2165
2166         if (sbi->s_sb_block != 1)
2167                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2168
2169         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2170                 int want_set = m->flags & MOPT_SET;
2171                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2172                     (m->flags & MOPT_CLEAR_ERR))
2173                         continue;
2174                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2175                         continue; /* skip if same as the default */
2176                 if ((want_set &&
2177                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2178                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2179                         continue; /* select Opt_noFoo vs Opt_Foo */
2180                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2181         }
2182
2183         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2184             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2185                 SEQ_OPTS_PRINT("resuid=%u",
2186                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2187         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2188             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2189                 SEQ_OPTS_PRINT("resgid=%u",
2190                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2191         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2192         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2193                 SEQ_OPTS_PUTS("errors=remount-ro");
2194         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2195                 SEQ_OPTS_PUTS("errors=continue");
2196         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2197                 SEQ_OPTS_PUTS("errors=panic");
2198         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2199                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2200         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2201                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2202         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2203                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2204         if (sb->s_flags & SB_I_VERSION)
2205                 SEQ_OPTS_PUTS("i_version");
2206         if (nodefs || sbi->s_stripe)
2207                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2208         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2209                         (sbi->s_mount_opt ^ def_mount_opt)) {
2210                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2211                         SEQ_OPTS_PUTS("data=journal");
2212                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2213                         SEQ_OPTS_PUTS("data=ordered");
2214                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2215                         SEQ_OPTS_PUTS("data=writeback");
2216         }
2217         if (nodefs ||
2218             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2219                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2220                                sbi->s_inode_readahead_blks);
2221
2222         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2223                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2224                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2225         if (nodefs || sbi->s_max_dir_size_kb)
2226                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2227         if (test_opt(sb, DATA_ERR_ABORT))
2228                 SEQ_OPTS_PUTS("data_err=abort");
2229         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2230                 SEQ_OPTS_PUTS("test_dummy_encryption");
2231
2232         ext4_show_quota_options(seq, sb);
2233         return 0;
2234 }
2235
2236 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2237 {
2238         return _ext4_show_options(seq, root->d_sb, 0);
2239 }
2240
2241 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2242 {
2243         struct super_block *sb = seq->private;
2244         int rc;
2245
2246         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2247         rc = _ext4_show_options(seq, sb, 1);
2248         seq_puts(seq, "\n");
2249         return rc;
2250 }
2251
2252 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2253                             int read_only)
2254 {
2255         struct ext4_sb_info *sbi = EXT4_SB(sb);
2256         int err = 0;
2257
2258         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2259                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2260                          "forcing read-only mode");
2261                 err = -EROFS;
2262                 goto done;
2263         }
2264         if (read_only)
2265                 goto done;
2266         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2267                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2268                          "running e2fsck is recommended");
2269         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2270                 ext4_msg(sb, KERN_WARNING,
2271                          "warning: mounting fs with errors, "
2272                          "running e2fsck is recommended");
2273         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2274                  le16_to_cpu(es->s_mnt_count) >=
2275                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2276                 ext4_msg(sb, KERN_WARNING,
2277                          "warning: maximal mount count reached, "
2278                          "running e2fsck is recommended");
2279         else if (le32_to_cpu(es->s_checkinterval) &&
2280                  (ext4_get_tstamp(es, s_lastcheck) +
2281                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2282                 ext4_msg(sb, KERN_WARNING,
2283                          "warning: checktime reached, "
2284                          "running e2fsck is recommended");
2285         if (!sbi->s_journal)
2286                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2287         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2288                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2289         le16_add_cpu(&es->s_mnt_count, 1);
2290         ext4_update_tstamp(es, s_mtime);
2291         if (sbi->s_journal)
2292                 ext4_set_feature_journal_needs_recovery(sb);
2293
2294         err = ext4_commit_super(sb, 1);
2295 done:
2296         if (test_opt(sb, DEBUG))
2297                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2298                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2299                         sb->s_blocksize,
2300                         sbi->s_groups_count,
2301                         EXT4_BLOCKS_PER_GROUP(sb),
2302                         EXT4_INODES_PER_GROUP(sb),
2303                         sbi->s_mount_opt, sbi->s_mount_opt2);
2304
2305         cleancache_init_fs(sb);
2306         return err;
2307 }
2308
2309 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2310 {
2311         struct ext4_sb_info *sbi = EXT4_SB(sb);
2312         struct flex_groups **old_groups, **new_groups;
2313         int size, i, j;
2314
2315         if (!sbi->s_log_groups_per_flex)
2316                 return 0;
2317
2318         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2319         if (size <= sbi->s_flex_groups_allocated)
2320                 return 0;
2321
2322         new_groups = kvzalloc(roundup_pow_of_two(size *
2323                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2324         if (!new_groups) {
2325                 ext4_msg(sb, KERN_ERR,
2326                          "not enough memory for %d flex group pointers", size);
2327                 return -ENOMEM;
2328         }
2329         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2330                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2331                                          sizeof(struct flex_groups)),
2332                                          GFP_KERNEL);
2333                 if (!new_groups[i]) {
2334                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2335                                 kvfree(new_groups[j]);
2336                         kvfree(new_groups);
2337                         ext4_msg(sb, KERN_ERR,
2338                                  "not enough memory for %d flex groups", size);
2339                         return -ENOMEM;
2340                 }
2341         }
2342         rcu_read_lock();
2343         old_groups = rcu_dereference(sbi->s_flex_groups);
2344         if (old_groups)
2345                 memcpy(new_groups, old_groups,
2346                        (sbi->s_flex_groups_allocated *
2347                         sizeof(struct flex_groups *)));
2348         rcu_read_unlock();
2349         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2350         sbi->s_flex_groups_allocated = size;
2351         if (old_groups)
2352                 ext4_kvfree_array_rcu(old_groups);
2353         return 0;
2354 }
2355
2356 static int ext4_fill_flex_info(struct super_block *sb)
2357 {
2358         struct ext4_sb_info *sbi = EXT4_SB(sb);
2359         struct ext4_group_desc *gdp = NULL;
2360         struct flex_groups *fg;
2361         ext4_group_t flex_group;
2362         int i, err;
2363
2364         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2365         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2366                 sbi->s_log_groups_per_flex = 0;
2367                 return 1;
2368         }
2369
2370         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2371         if (err)
2372                 goto failed;
2373
2374         for (i = 0; i < sbi->s_groups_count; i++) {
2375                 gdp = ext4_get_group_desc(sb, i, NULL);
2376
2377                 flex_group = ext4_flex_group(sbi, i);
2378                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2379                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2380                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2381                              &fg->free_clusters);
2382                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2383         }
2384
2385         return 1;
2386 failed:
2387         return 0;
2388 }
2389
2390 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2391                                    struct ext4_group_desc *gdp)
2392 {
2393         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2394         __u16 crc = 0;
2395         __le32 le_group = cpu_to_le32(block_group);
2396         struct ext4_sb_info *sbi = EXT4_SB(sb);
2397
2398         if (ext4_has_metadata_csum(sbi->s_sb)) {
2399                 /* Use new metadata_csum algorithm */
2400                 __u32 csum32;
2401                 __u16 dummy_csum = 0;
2402
2403                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2404                                      sizeof(le_group));
2405                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2406                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2407                                      sizeof(dummy_csum));
2408                 offset += sizeof(dummy_csum);
2409                 if (offset < sbi->s_desc_size)
2410                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2411                                              sbi->s_desc_size - offset);
2412
2413                 crc = csum32 & 0xFFFF;
2414                 goto out;
2415         }
2416
2417         /* old crc16 code */
2418         if (!ext4_has_feature_gdt_csum(sb))
2419                 return 0;
2420
2421         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2422         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2423         crc = crc16(crc, (__u8 *)gdp, offset);
2424         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2425         /* for checksum of struct ext4_group_desc do the rest...*/
2426         if (ext4_has_feature_64bit(sb) && offset < sbi->s_desc_size)
2427                 crc = crc16(crc, (__u8 *)gdp + offset,
2428                             sbi->s_desc_size - offset);
2429
2430 out:
2431         return cpu_to_le16(crc);
2432 }
2433
2434 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2435                                 struct ext4_group_desc *gdp)
2436 {
2437         if (ext4_has_group_desc_csum(sb) &&
2438             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2439                 return 0;
2440
2441         return 1;
2442 }
2443
2444 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2445                               struct ext4_group_desc *gdp)
2446 {
2447         if (!ext4_has_group_desc_csum(sb))
2448                 return;
2449         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2450 }
2451
2452 /* Called at mount-time, super-block is locked */
2453 static int ext4_check_descriptors(struct super_block *sb,
2454                                   ext4_fsblk_t sb_block,
2455                                   ext4_group_t *first_not_zeroed)
2456 {
2457         struct ext4_sb_info *sbi = EXT4_SB(sb);
2458         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2459         ext4_fsblk_t last_block;
2460         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2461         ext4_fsblk_t block_bitmap;
2462         ext4_fsblk_t inode_bitmap;
2463         ext4_fsblk_t inode_table;
2464         int flexbg_flag = 0;
2465         ext4_group_t i, grp = sbi->s_groups_count;
2466
2467         if (ext4_has_feature_flex_bg(sb))
2468                 flexbg_flag = 1;
2469
2470         ext4_debug("Checking group descriptors");
2471
2472         for (i = 0; i < sbi->s_groups_count; i++) {
2473                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2474
2475                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2476                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2477                 else
2478                         last_block = first_block +
2479                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2480
2481                 if ((grp == sbi->s_groups_count) &&
2482                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2483                         grp = i;
2484
2485                 block_bitmap = ext4_block_bitmap(sb, gdp);
2486                 if (block_bitmap == sb_block) {
2487                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2488                                  "Block bitmap for group %u overlaps "
2489                                  "superblock", i);
2490                         if (!sb_rdonly(sb))
2491                                 return 0;
2492                 }
2493                 if (block_bitmap >= sb_block + 1 &&
2494                     block_bitmap <= last_bg_block) {
2495                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2496                                  "Block bitmap for group %u overlaps "
2497                                  "block group descriptors", i);
2498                         if (!sb_rdonly(sb))
2499                                 return 0;
2500                 }
2501                 if (block_bitmap < first_block || block_bitmap > last_block) {
2502                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2503                                "Block bitmap for group %u not in group "
2504                                "(block %llu)!", i, block_bitmap);
2505                         return 0;
2506                 }
2507                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2508                 if (inode_bitmap == sb_block) {
2509                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2510                                  "Inode bitmap for group %u overlaps "
2511                                  "superblock", i);
2512                         if (!sb_rdonly(sb))
2513                                 return 0;
2514                 }
2515                 if (inode_bitmap >= sb_block + 1 &&
2516                     inode_bitmap <= last_bg_block) {
2517                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2518                                  "Inode bitmap for group %u overlaps "
2519                                  "block group descriptors", i);
2520                         if (!sb_rdonly(sb))
2521                                 return 0;
2522                 }
2523                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2524                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2525                                "Inode bitmap for group %u not in group "
2526                                "(block %llu)!", i, inode_bitmap);
2527                         return 0;
2528                 }
2529                 inode_table = ext4_inode_table(sb, gdp);
2530                 if (inode_table == sb_block) {
2531                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2532                                  "Inode table for group %u overlaps "
2533                                  "superblock", i);
2534                         if (!sb_rdonly(sb))
2535                                 return 0;
2536                 }
2537                 if (inode_table >= sb_block + 1 &&
2538                     inode_table <= last_bg_block) {
2539                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2540                                  "Inode table for group %u overlaps "
2541                                  "block group descriptors", i);
2542                         if (!sb_rdonly(sb))
2543                                 return 0;
2544                 }
2545                 if (inode_table < first_block ||
2546                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2547                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2548                                "Inode table for group %u not in group "
2549                                "(block %llu)!", i, inode_table);
2550                         return 0;
2551                 }
2552                 ext4_lock_group(sb, i);
2553                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2554                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2555                                  "Checksum for group %u failed (%u!=%u)",
2556                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2557                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2558                         if (!sb_rdonly(sb)) {
2559                                 ext4_unlock_group(sb, i);
2560                                 return 0;
2561                         }
2562                 }
2563                 ext4_unlock_group(sb, i);
2564                 if (!flexbg_flag)
2565                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2566         }
2567         if (NULL != first_not_zeroed)
2568                 *first_not_zeroed = grp;
2569         return 1;
2570 }
2571
2572 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2573  * the superblock) which were deleted from all directories, but held open by
2574  * a process at the time of a crash.  We walk the list and try to delete these
2575  * inodes at recovery time (only with a read-write filesystem).
2576  *
2577  * In order to keep the orphan inode chain consistent during traversal (in
2578  * case of crash during recovery), we link each inode into the superblock
2579  * orphan list_head and handle it the same way as an inode deletion during
2580  * normal operation (which journals the operations for us).
2581  *
2582  * We only do an iget() and an iput() on each inode, which is very safe if we
2583  * accidentally point at an in-use or already deleted inode.  The worst that
2584  * can happen in this case is that we get a "bit already cleared" message from
2585  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2586  * e2fsck was run on this filesystem, and it must have already done the orphan
2587  * inode cleanup for us, so we can safely abort without any further action.
2588  */
2589 static void ext4_orphan_cleanup(struct super_block *sb,
2590                                 struct ext4_super_block *es)
2591 {
2592         unsigned int s_flags = sb->s_flags;
2593         int ret, nr_orphans = 0, nr_truncates = 0;
2594 #ifdef CONFIG_QUOTA
2595         int quota_update = 0;
2596         int i;
2597 #endif
2598         if (!es->s_last_orphan) {
2599                 jbd_debug(4, "no orphan inodes to clean up\n");
2600                 return;
2601         }
2602
2603         if (bdev_read_only(sb->s_bdev)) {
2604                 ext4_msg(sb, KERN_ERR, "write access "
2605                         "unavailable, skipping orphan cleanup");
2606                 return;
2607         }
2608
2609         /* Check if feature set would not allow a r/w mount */
2610         if (!ext4_feature_set_ok(sb, 0)) {
2611                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2612                          "unknown ROCOMPAT features");
2613                 return;
2614         }
2615
2616         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2617                 /* don't clear list on RO mount w/ errors */
2618                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2619                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2620                                   "clearing orphan list.\n");
2621                         es->s_last_orphan = 0;
2622                 }
2623                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2624                 return;
2625         }
2626
2627         if (s_flags & SB_RDONLY) {
2628                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2629                 sb->s_flags &= ~SB_RDONLY;
2630         }
2631 #ifdef CONFIG_QUOTA
2632         /*
2633          * Turn on quotas which were not enabled for read-only mounts if
2634          * filesystem has quota feature, so that they are updated correctly.
2635          */
2636         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2637                 int ret = ext4_enable_quotas(sb);
2638
2639                 if (!ret)
2640                         quota_update = 1;
2641                 else
2642                         ext4_msg(sb, KERN_ERR,
2643                                 "Cannot turn on quotas: error %d", ret);
2644         }
2645
2646         /* Turn on journaled quotas used for old sytle */
2647         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2648                 if (EXT4_SB(sb)->s_qf_names[i]) {
2649                         int ret = ext4_quota_on_mount(sb, i);
2650
2651                         if (!ret)
2652                                 quota_update = 1;
2653                         else
2654                                 ext4_msg(sb, KERN_ERR,
2655                                         "Cannot turn on journaled "
2656                                         "quota: type %d: error %d", i, ret);
2657                 }
2658         }
2659 #endif
2660
2661         while (es->s_last_orphan) {
2662                 struct inode *inode;
2663
2664                 /*
2665                  * We may have encountered an error during cleanup; if
2666                  * so, skip the rest.
2667                  */
2668                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2669                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2670                         es->s_last_orphan = 0;
2671                         break;
2672                 }
2673
2674                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2675                 if (IS_ERR(inode)) {
2676                         es->s_last_orphan = 0;
2677                         break;
2678                 }
2679
2680                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2681                 dquot_initialize(inode);
2682                 if (inode->i_nlink) {
2683                         if (test_opt(sb, DEBUG))
2684                                 ext4_msg(sb, KERN_DEBUG,
2685                                         "%s: truncating inode %lu to %lld bytes",
2686                                         __func__, inode->i_ino, inode->i_size);
2687                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2688                                   inode->i_ino, inode->i_size);
2689                         inode_lock(inode);
2690                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2691                         ret = ext4_truncate(inode);
2692                         if (ret) {
2693                                 /*
2694                                  * We need to clean up the in-core orphan list
2695                                  * manually if ext4_truncate() failed to get a
2696                                  * transaction handle.
2697                                  */
2698                                 ext4_orphan_del(NULL, inode);
2699                                 ext4_std_error(inode->i_sb, ret);
2700                         }
2701                         inode_unlock(inode);
2702                         nr_truncates++;
2703                 } else {
2704                         if (test_opt(sb, DEBUG))
2705                                 ext4_msg(sb, KERN_DEBUG,
2706                                         "%s: deleting unreferenced inode %lu",
2707                                         __func__, inode->i_ino);
2708                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2709                                   inode->i_ino);
2710                         nr_orphans++;
2711                 }
2712                 iput(inode);  /* The delete magic happens here! */
2713         }
2714
2715 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2716
2717         if (nr_orphans)
2718                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2719                        PLURAL(nr_orphans));
2720         if (nr_truncates)
2721                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2722                        PLURAL(nr_truncates));
2723 #ifdef CONFIG_QUOTA
2724         /* Turn off quotas if they were enabled for orphan cleanup */
2725         if (quota_update) {
2726                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2727                         if (sb_dqopt(sb)->files[i])
2728                                 dquot_quota_off(sb, i);
2729                 }
2730         }
2731 #endif
2732         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2733 }
2734
2735 /*
2736  * Maximal extent format file size.
2737  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2738  * extent format containers, within a sector_t, and within i_blocks
2739  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2740  * so that won't be a limiting factor.
2741  *
2742  * However there is other limiting factor. We do store extents in the form
2743  * of starting block and length, hence the resulting length of the extent
2744  * covering maximum file size must fit into on-disk format containers as
2745  * well. Given that length is always by 1 unit bigger than max unit (because
2746  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2747  *
2748  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2749  */
2750 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2751 {
2752         loff_t res;
2753         loff_t upper_limit = MAX_LFS_FILESIZE;
2754
2755         /* small i_blocks in vfs inode? */
2756         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2757                 /*
2758                  * CONFIG_LBDAF is not enabled implies the inode
2759                  * i_block represent total blocks in 512 bytes
2760                  * 32 == size of vfs inode i_blocks * 8
2761                  */
2762                 upper_limit = (1LL << 32) - 1;
2763
2764                 /* total blocks in file system block size */
2765                 upper_limit >>= (blkbits - 9);
2766                 upper_limit <<= blkbits;
2767         }
2768
2769         /*
2770          * 32-bit extent-start container, ee_block. We lower the maxbytes
2771          * by one fs block, so ee_len can cover the extent of maximum file
2772          * size
2773          */
2774         res = (1LL << 32) - 1;
2775         res <<= blkbits;
2776
2777         /* Sanity check against vm- & vfs- imposed limits */
2778         if (res > upper_limit)
2779                 res = upper_limit;
2780
2781         return res;
2782 }
2783
2784 /*
2785  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2786  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2787  * We need to be 1 filesystem block less than the 2^48 sector limit.
2788  */
2789 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2790 {
2791         loff_t res = EXT4_NDIR_BLOCKS;
2792         int meta_blocks;
2793         loff_t upper_limit;
2794         /* This is calculated to be the largest file size for a dense, block
2795          * mapped file such that the file's total number of 512-byte sectors,
2796          * including data and all indirect blocks, does not exceed (2^48 - 1).
2797          *
2798          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2799          * number of 512-byte sectors of the file.
2800          */
2801
2802         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2803                 /*
2804                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2805                  * the inode i_block field represents total file blocks in
2806                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2807                  */
2808                 upper_limit = (1LL << 32) - 1;
2809
2810                 /* total blocks in file system block size */
2811                 upper_limit >>= (bits - 9);
2812
2813         } else {
2814                 /*
2815                  * We use 48 bit ext4_inode i_blocks
2816                  * With EXT4_HUGE_FILE_FL set the i_blocks
2817                  * represent total number of blocks in
2818                  * file system block size
2819                  */
2820                 upper_limit = (1LL << 48) - 1;
2821
2822         }
2823
2824         /* indirect blocks */
2825         meta_blocks = 1;
2826         /* double indirect blocks */
2827         meta_blocks += 1 + (1LL << (bits-2));
2828         /* tripple indirect blocks */
2829         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2830
2831         upper_limit -= meta_blocks;
2832         upper_limit <<= bits;
2833
2834         res += 1LL << (bits-2);
2835         res += 1LL << (2*(bits-2));
2836         res += 1LL << (3*(bits-2));
2837         res <<= bits;
2838         if (res > upper_limit)
2839                 res = upper_limit;
2840
2841         if (res > MAX_LFS_FILESIZE)
2842                 res = MAX_LFS_FILESIZE;
2843
2844         return res;
2845 }
2846
2847 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2848                                    ext4_fsblk_t logical_sb_block, int nr)
2849 {
2850         struct ext4_sb_info *sbi = EXT4_SB(sb);
2851         ext4_group_t bg, first_meta_bg;
2852         int has_super = 0;
2853
2854         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2855
2856         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2857                 return logical_sb_block + nr + 1;
2858         bg = sbi->s_desc_per_block * nr;
2859         if (ext4_bg_has_super(sb, bg))
2860                 has_super = 1;
2861
2862         /*
2863          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2864          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2865          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2866          * compensate.
2867          */
2868         if (sb->s_blocksize == 1024 && nr == 0 &&
2869             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2870                 has_super++;
2871
2872         return (has_super + ext4_group_first_block_no(sb, bg));
2873 }
2874
2875 /**
2876  * ext4_get_stripe_size: Get the stripe size.
2877  * @sbi: In memory super block info
2878  *
2879  * If we have specified it via mount option, then
2880  * use the mount option value. If the value specified at mount time is
2881  * greater than the blocks per group use the super block value.
2882  * If the super block value is greater than blocks per group return 0.
2883  * Allocator needs it be less than blocks per group.
2884  *
2885  */
2886 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2887 {
2888         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2889         unsigned long stripe_width =
2890                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2891         int ret;
2892
2893         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2894                 ret = sbi->s_stripe;
2895         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2896                 ret = stripe_width;
2897         else if (stride && stride <= sbi->s_blocks_per_group)
2898                 ret = stride;
2899         else
2900                 ret = 0;
2901
2902         /*
2903          * If the stripe width is 1, this makes no sense and
2904          * we set it to 0 to turn off stripe handling code.
2905          */
2906         if (ret <= 1)
2907                 ret = 0;
2908
2909         return ret;
2910 }
2911
2912 /*
2913  * Check whether this filesystem can be mounted based on
2914  * the features present and the RDONLY/RDWR mount requested.
2915  * Returns 1 if this filesystem can be mounted as requested,
2916  * 0 if it cannot be.
2917  */
2918 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2919 {
2920         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2921                 ext4_msg(sb, KERN_ERR,
2922                         "Couldn't mount because of "
2923                         "unsupported optional features (%x)",
2924                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2925                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2926                 return 0;
2927         }
2928
2929         if (readonly)
2930                 return 1;
2931
2932         if (ext4_has_feature_readonly(sb)) {
2933                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2934                 sb->s_flags |= SB_RDONLY;
2935                 return 1;
2936         }
2937
2938         /* Check that feature set is OK for a read-write mount */
2939         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2940                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2941                          "unsupported optional features (%x)",
2942                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2943                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2944                 return 0;
2945         }
2946         /*
2947          * Large file size enabled file system can only be mounted
2948          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2949          */
2950         if (ext4_has_feature_huge_file(sb)) {
2951                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2952                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2953                                  "cannot be mounted RDWR without "
2954                                  "CONFIG_LBDAF");
2955                         return 0;
2956                 }
2957         }
2958         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2959                 ext4_msg(sb, KERN_ERR,
2960                          "Can't support bigalloc feature without "
2961                          "extents feature\n");
2962                 return 0;
2963         }
2964
2965 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
2966         if (!readonly && (ext4_has_feature_quota(sb) ||
2967                           ext4_has_feature_project(sb))) {
2968                 ext4_msg(sb, KERN_ERR,
2969                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
2970                 return 0;
2971         }
2972 #endif  /* CONFIG_QUOTA */
2973         return 1;
2974 }
2975
2976 /*
2977  * This function is called once a day if we have errors logged
2978  * on the file system
2979  */
2980 static void print_daily_error_info(struct timer_list *t)
2981 {
2982         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2983         struct super_block *sb = sbi->s_sb;
2984         struct ext4_super_block *es = sbi->s_es;
2985
2986         if (es->s_error_count)
2987                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2988                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2989                          le32_to_cpu(es->s_error_count));
2990         if (es->s_first_error_time) {
2991                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
2992                        sb->s_id,
2993                        ext4_get_tstamp(es, s_first_error_time),
2994                        (int) sizeof(es->s_first_error_func),
2995                        es->s_first_error_func,
2996                        le32_to_cpu(es->s_first_error_line));
2997                 if (es->s_first_error_ino)
2998                         printk(KERN_CONT ": inode %u",
2999                                le32_to_cpu(es->s_first_error_ino));
3000                 if (es->s_first_error_block)
3001                         printk(KERN_CONT ": block %llu", (unsigned long long)
3002                                le64_to_cpu(es->s_first_error_block));
3003                 printk(KERN_CONT "\n");
3004         }
3005         if (es->s_last_error_time) {
3006                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3007                        sb->s_id,
3008                        ext4_get_tstamp(es, s_last_error_time),
3009                        (int) sizeof(es->s_last_error_func),
3010                        es->s_last_error_func,
3011                        le32_to_cpu(es->s_last_error_line));
3012                 if (es->s_last_error_ino)
3013                         printk(KERN_CONT ": inode %u",
3014                                le32_to_cpu(es->s_last_error_ino));
3015                 if (es->s_last_error_block)
3016                         printk(KERN_CONT ": block %llu", (unsigned long long)
3017                                le64_to_cpu(es->s_last_error_block));
3018                 printk(KERN_CONT "\n");
3019         }
3020         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3021 }
3022
3023 /* Find next suitable group and run ext4_init_inode_table */
3024 static int ext4_run_li_request(struct ext4_li_request *elr)
3025 {
3026         struct ext4_group_desc *gdp = NULL;
3027         ext4_group_t group, ngroups;
3028         struct super_block *sb;
3029         int ret = 0;
3030         u64 start_time;
3031
3032         sb = elr->lr_super;
3033         ngroups = EXT4_SB(sb)->s_groups_count;
3034
3035         for (group = elr->lr_next_group; group < ngroups; group++) {
3036                 gdp = ext4_get_group_desc(sb, group, NULL);
3037                 if (!gdp) {
3038                         ret = 1;
3039                         break;
3040                 }
3041
3042                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3043                         break;
3044         }
3045
3046         if (group >= ngroups)
3047                 ret = 1;
3048
3049         if (!ret) {
3050                 start_time = ktime_get_real_ns();
3051                 ret = ext4_init_inode_table(sb, group,
3052                                             elr->lr_timeout ? 0 : 1);
3053                 if (elr->lr_timeout == 0) {
3054                         elr->lr_timeout = nsecs_to_jiffies((ktime_get_real_ns() - start_time) *
3055                                   elr->lr_sbi->s_li_wait_mult);
3056                 }
3057                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3058                 elr->lr_next_group = group + 1;
3059         }
3060         return ret;
3061 }
3062
3063 /*
3064  * Remove lr_request from the list_request and free the
3065  * request structure. Should be called with li_list_mtx held
3066  */
3067 static void ext4_remove_li_request(struct ext4_li_request *elr)
3068 {
3069         struct ext4_sb_info *sbi;
3070
3071         if (!elr)
3072                 return;
3073
3074         sbi = elr->lr_sbi;
3075
3076         list_del(&elr->lr_request);
3077         sbi->s_li_request = NULL;
3078         kfree(elr);
3079 }
3080
3081 static void ext4_unregister_li_request(struct super_block *sb)
3082 {
3083         mutex_lock(&ext4_li_mtx);
3084         if (!ext4_li_info) {
3085                 mutex_unlock(&ext4_li_mtx);
3086                 return;
3087         }
3088
3089         mutex_lock(&ext4_li_info->li_list_mtx);
3090         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3091         mutex_unlock(&ext4_li_info->li_list_mtx);
3092         mutex_unlock(&ext4_li_mtx);
3093 }
3094
3095 static struct task_struct *ext4_lazyinit_task;
3096
3097 /*
3098  * This is the function where ext4lazyinit thread lives. It walks
3099  * through the request list searching for next scheduled filesystem.
3100  * When such a fs is found, run the lazy initialization request
3101  * (ext4_rn_li_request) and keep track of the time spend in this
3102  * function. Based on that time we compute next schedule time of
3103  * the request. When walking through the list is complete, compute
3104  * next waking time and put itself into sleep.
3105  */
3106 static int ext4_lazyinit_thread(void *arg)
3107 {
3108         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3109         struct list_head *pos, *n;
3110         struct ext4_li_request *elr;
3111         unsigned long next_wakeup, cur;
3112
3113         BUG_ON(NULL == eli);
3114         set_freezable();
3115
3116 cont_thread:
3117         while (true) {
3118                 next_wakeup = MAX_JIFFY_OFFSET;
3119
3120                 mutex_lock(&eli->li_list_mtx);
3121                 if (list_empty(&eli->li_request_list)) {
3122                         mutex_unlock(&eli->li_list_mtx);
3123                         goto exit_thread;
3124                 }
3125                 list_for_each_safe(pos, n, &eli->li_request_list) {
3126                         int err = 0;
3127                         int progress = 0;
3128                         elr = list_entry(pos, struct ext4_li_request,
3129                                          lr_request);
3130
3131                         if (time_before(jiffies, elr->lr_next_sched)) {
3132                                 if (time_before(elr->lr_next_sched, next_wakeup))
3133                                         next_wakeup = elr->lr_next_sched;
3134                                 continue;
3135                         }
3136                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3137                                 if (sb_start_write_trylock(elr->lr_super)) {
3138                                         progress = 1;
3139                                         /*
3140                                          * We hold sb->s_umount, sb can not
3141                                          * be removed from the list, it is
3142                                          * now safe to drop li_list_mtx
3143                                          */
3144                                         mutex_unlock(&eli->li_list_mtx);
3145                                         err = ext4_run_li_request(elr);
3146                                         sb_end_write(elr->lr_super);
3147                                         mutex_lock(&eli->li_list_mtx);
3148                                         n = pos->next;
3149                                 }
3150                                 up_read((&elr->lr_super->s_umount));
3151                         }
3152                         /* error, remove the lazy_init job */
3153                         if (err) {
3154                                 ext4_remove_li_request(elr);
3155                                 continue;
3156                         }
3157                         if (!progress) {
3158                                 elr->lr_next_sched = jiffies +
3159                                         (prandom_u32()
3160                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3161                         }
3162                         if (time_before(elr->lr_next_sched, next_wakeup))
3163                                 next_wakeup = elr->lr_next_sched;
3164                 }
3165                 mutex_unlock(&eli->li_list_mtx);
3166
3167                 try_to_freeze();
3168
3169                 cur = jiffies;
3170                 if ((time_after_eq(cur, next_wakeup)) ||
3171                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3172                         cond_resched();
3173                         continue;
3174                 }
3175
3176                 schedule_timeout_interruptible(next_wakeup - cur);
3177
3178                 if (kthread_should_stop()) {
3179                         ext4_clear_request_list();
3180                         goto exit_thread;
3181                 }
3182         }
3183
3184 exit_thread:
3185         /*
3186          * It looks like the request list is empty, but we need
3187          * to check it under the li_list_mtx lock, to prevent any
3188          * additions into it, and of course we should lock ext4_li_mtx
3189          * to atomically free the list and ext4_li_info, because at
3190          * this point another ext4 filesystem could be registering
3191          * new one.
3192          */
3193         mutex_lock(&ext4_li_mtx);
3194         mutex_lock(&eli->li_list_mtx);
3195         if (!list_empty(&eli->li_request_list)) {
3196                 mutex_unlock(&eli->li_list_mtx);
3197                 mutex_unlock(&ext4_li_mtx);
3198                 goto cont_thread;
3199         }
3200         mutex_unlock(&eli->li_list_mtx);
3201         kfree(ext4_li_info);
3202         ext4_li_info = NULL;
3203         mutex_unlock(&ext4_li_mtx);
3204
3205         return 0;
3206 }
3207
3208 static void ext4_clear_request_list(void)
3209 {
3210         struct list_head *pos, *n;
3211         struct ext4_li_request *elr;
3212
3213         mutex_lock(&ext4_li_info->li_list_mtx);
3214         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3215                 elr = list_entry(pos, struct ext4_li_request,
3216                                  lr_request);
3217                 ext4_remove_li_request(elr);
3218         }
3219         mutex_unlock(&ext4_li_info->li_list_mtx);
3220 }
3221
3222 static int ext4_run_lazyinit_thread(void)
3223 {
3224         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3225                                          ext4_li_info, "ext4lazyinit");
3226         if (IS_ERR(ext4_lazyinit_task)) {
3227                 int err = PTR_ERR(ext4_lazyinit_task);
3228                 ext4_clear_request_list();
3229                 kfree(ext4_li_info);
3230                 ext4_li_info = NULL;
3231                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3232                                  "initialization thread\n",
3233                                  err);
3234                 return err;
3235         }
3236         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3237         return 0;
3238 }
3239
3240 /*
3241  * Check whether it make sense to run itable init. thread or not.
3242  * If there is at least one uninitialized inode table, return
3243  * corresponding group number, else the loop goes through all
3244  * groups and return total number of groups.
3245  */
3246 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3247 {
3248         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3249         struct ext4_group_desc *gdp = NULL;
3250
3251         if (!ext4_has_group_desc_csum(sb))
3252                 return ngroups;
3253
3254         for (group = 0; group < ngroups; group++) {
3255                 gdp = ext4_get_group_desc(sb, group, NULL);
3256                 if (!gdp)
3257                         continue;
3258
3259                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3260                         break;
3261         }
3262
3263         return group;
3264 }
3265
3266 static int ext4_li_info_new(void)
3267 {
3268         struct ext4_lazy_init *eli = NULL;
3269
3270         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3271         if (!eli)
3272                 return -ENOMEM;
3273
3274         INIT_LIST_HEAD(&eli->li_request_list);
3275         mutex_init(&eli->li_list_mtx);
3276
3277         eli->li_state |= EXT4_LAZYINIT_QUIT;
3278
3279         ext4_li_info = eli;
3280
3281         return 0;
3282 }
3283
3284 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3285                                             ext4_group_t start)
3286 {
3287         struct ext4_sb_info *sbi = EXT4_SB(sb);
3288         struct ext4_li_request *elr;
3289
3290         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3291         if (!elr)
3292                 return NULL;
3293
3294         elr->lr_super = sb;
3295         elr->lr_sbi = sbi;
3296         elr->lr_next_group = start;
3297
3298         /*
3299          * Randomize first schedule time of the request to
3300          * spread the inode table initialization requests
3301          * better.
3302          */
3303         elr->lr_next_sched = jiffies + (prandom_u32() %
3304                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3305         return elr;
3306 }
3307
3308 int ext4_register_li_request(struct super_block *sb,
3309                              ext4_group_t first_not_zeroed)
3310 {
3311         struct ext4_sb_info *sbi = EXT4_SB(sb);
3312         struct ext4_li_request *elr = NULL;
3313         ext4_group_t ngroups = sbi->s_groups_count;
3314         int ret = 0;
3315
3316         mutex_lock(&ext4_li_mtx);
3317         if (sbi->s_li_request != NULL) {
3318                 /*
3319                  * Reset timeout so it can be computed again, because
3320                  * s_li_wait_mult might have changed.
3321                  */
3322                 sbi->s_li_request->lr_timeout = 0;
3323                 goto out;
3324         }
3325
3326         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3327             !test_opt(sb, INIT_INODE_TABLE))
3328                 goto out;
3329
3330         elr = ext4_li_request_new(sb, first_not_zeroed);
3331         if (!elr) {
3332                 ret = -ENOMEM;
3333                 goto out;
3334         }
3335
3336         if (NULL == ext4_li_info) {
3337                 ret = ext4_li_info_new();
3338                 if (ret)
3339                         goto out;
3340         }
3341
3342         mutex_lock(&ext4_li_info->li_list_mtx);
3343         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3344         mutex_unlock(&ext4_li_info->li_list_mtx);
3345
3346         sbi->s_li_request = elr;
3347         /*
3348          * set elr to NULL here since it has been inserted to
3349          * the request_list and the removal and free of it is
3350          * handled by ext4_clear_request_list from now on.
3351          */
3352         elr = NULL;
3353
3354         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3355                 ret = ext4_run_lazyinit_thread();
3356                 if (ret)
3357                         goto out;
3358         }
3359 out:
3360         mutex_unlock(&ext4_li_mtx);
3361         if (ret)
3362                 kfree(elr);
3363         return ret;
3364 }
3365
3366 /*
3367  * We do not need to lock anything since this is called on
3368  * module unload.
3369  */
3370 static void ext4_destroy_lazyinit_thread(void)
3371 {
3372         /*
3373          * If thread exited earlier
3374          * there's nothing to be done.
3375          */
3376         if (!ext4_li_info || !ext4_lazyinit_task)
3377                 return;
3378
3379         kthread_stop(ext4_lazyinit_task);
3380 }
3381
3382 static int set_journal_csum_feature_set(struct super_block *sb)
3383 {
3384         int ret = 1;
3385         int compat, incompat;
3386         struct ext4_sb_info *sbi = EXT4_SB(sb);
3387
3388         if (ext4_has_metadata_csum(sb)) {
3389                 /* journal checksum v3 */
3390                 compat = 0;
3391                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3392         } else {
3393                 /* journal checksum v1 */
3394                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3395                 incompat = 0;
3396         }
3397
3398         jbd2_journal_clear_features(sbi->s_journal,
3399                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3400                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3401                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3402         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3403                 ret = jbd2_journal_set_features(sbi->s_journal,
3404                                 compat, 0,
3405                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3406                                 incompat);
3407         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3408                 ret = jbd2_journal_set_features(sbi->s_journal,
3409                                 compat, 0,
3410                                 incompat);
3411                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3412                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3413         } else {
3414                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3415                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3416         }
3417
3418         return ret;
3419 }
3420
3421 /*
3422  * Note: calculating the overhead so we can be compatible with
3423  * historical BSD practice is quite difficult in the face of
3424  * clusters/bigalloc.  This is because multiple metadata blocks from
3425  * different block group can end up in the same allocation cluster.
3426  * Calculating the exact overhead in the face of clustered allocation
3427  * requires either O(all block bitmaps) in memory or O(number of block
3428  * groups**2) in time.  We will still calculate the superblock for
3429  * older file systems --- and if we come across with a bigalloc file
3430  * system with zero in s_overhead_clusters the estimate will be close to
3431  * correct especially for very large cluster sizes --- but for newer
3432  * file systems, it's better to calculate this figure once at mkfs
3433  * time, and store it in the superblock.  If the superblock value is
3434  * present (even for non-bigalloc file systems), we will use it.
3435  */
3436 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3437                           char *buf)
3438 {
3439         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3440         struct ext4_group_desc  *gdp;
3441         ext4_fsblk_t            first_block, last_block, b;
3442         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3443         int                     s, j, count = 0;
3444         int                     has_super = ext4_bg_has_super(sb, grp);
3445
3446         if (!ext4_has_feature_bigalloc(sb))
3447                 return (has_super + ext4_bg_num_gdb(sb, grp) +
3448                         (has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
3449                         sbi->s_itb_per_group + 2);
3450
3451         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3452                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3453         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3454         for (i = 0; i < ngroups; i++) {
3455                 gdp = ext4_get_group_desc(sb, i, NULL);
3456                 b = ext4_block_bitmap(sb, gdp);
3457                 if (b >= first_block && b <= last_block) {
3458                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3459                         count++;
3460                 }
3461                 b = ext4_inode_bitmap(sb, gdp);
3462                 if (b >= first_block && b <= last_block) {
3463                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3464                         count++;
3465                 }
3466                 b = ext4_inode_table(sb, gdp);
3467                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3468                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3469                                 int c = EXT4_B2C(sbi, b - first_block);
3470                                 ext4_set_bit(c, buf);
3471                                 count++;
3472                         }
3473                 if (i != grp)
3474                         continue;
3475                 s = 0;
3476                 if (ext4_bg_has_super(sb, grp)) {
3477                         ext4_set_bit(s++, buf);
3478                         count++;
3479                 }
3480                 j = ext4_bg_num_gdb(sb, grp);
3481                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3482                         ext4_error(sb, "Invalid number of block group "
3483                                    "descriptor blocks: %d", j);
3484                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3485                 }
3486                 count += j;
3487                 for (; j > 0; j--)
3488                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3489         }
3490         if (!count)
3491                 return 0;
3492         return EXT4_CLUSTERS_PER_GROUP(sb) -
3493                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3494 }
3495
3496 /*
3497  * Compute the overhead and stash it in sbi->s_overhead
3498  */
3499 int ext4_calculate_overhead(struct super_block *sb)
3500 {
3501         struct ext4_sb_info *sbi = EXT4_SB(sb);
3502         struct ext4_super_block *es = sbi->s_es;
3503         struct inode *j_inode;
3504         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3505         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3506         ext4_fsblk_t overhead = 0;
3507         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3508
3509         if (!buf)
3510                 return -ENOMEM;
3511
3512         /*
3513          * Compute the overhead (FS structures).  This is constant
3514          * for a given filesystem unless the number of block groups
3515          * changes so we cache the previous value until it does.
3516          */
3517
3518         /*
3519          * All of the blocks before first_data_block are overhead
3520          */
3521         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3522
3523         /*
3524          * Add the overhead found in each block group
3525          */
3526         for (i = 0; i < ngroups; i++) {
3527                 int blks;
3528
3529                 blks = count_overhead(sb, i, buf);
3530                 overhead += blks;
3531                 if (blks)
3532                         memset(buf, 0, PAGE_SIZE);
3533                 cond_resched();
3534         }
3535
3536         /*
3537          * Add the internal journal blocks whether the journal has been
3538          * loaded or not
3539          */
3540         if (sbi->s_journal && !sbi->journal_bdev)
3541                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3542         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3543                 /* j_inum for internal journal is non-zero */
3544                 j_inode = ext4_get_journal_inode(sb, j_inum);
3545                 if (j_inode) {
3546                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3547                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3548                         iput(j_inode);
3549                 } else {
3550                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3551                 }
3552         }
3553         sbi->s_overhead = overhead;
3554         smp_wmb();
3555         free_page((unsigned long) buf);
3556         return 0;
3557 }
3558
3559 static void ext4_set_resv_clusters(struct super_block *sb)
3560 {
3561         ext4_fsblk_t resv_clusters;
3562         struct ext4_sb_info *sbi = EXT4_SB(sb);
3563
3564         /*
3565          * There's no need to reserve anything when we aren't using extents.
3566          * The space estimates are exact, there are no unwritten extents,
3567          * hole punching doesn't need new metadata... This is needed especially
3568          * to keep ext2/3 backward compatibility.
3569          */
3570         if (!ext4_has_feature_extents(sb))
3571                 return;
3572         /*
3573          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3574          * This should cover the situations where we can not afford to run
3575          * out of space like for example punch hole, or converting
3576          * unwritten extents in delalloc path. In most cases such
3577          * allocation would require 1, or 2 blocks, higher numbers are
3578          * very rare.
3579          */
3580         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3581                          sbi->s_cluster_bits);
3582
3583         do_div(resv_clusters, 50);
3584         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3585
3586         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3587 }
3588
3589 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3590 {
3591         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3592         char *orig_data = kstrdup(data, GFP_KERNEL);
3593         struct buffer_head *bh, **group_desc;
3594         struct ext4_super_block *es = NULL;
3595         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3596         struct flex_groups **flex_groups;
3597         ext4_fsblk_t block;
3598         ext4_fsblk_t sb_block = get_sb_block(&data);
3599         ext4_fsblk_t logical_sb_block;
3600         unsigned long offset = 0;
3601         unsigned long journal_devnum = 0;
3602         unsigned long def_mount_opts;
3603         struct inode *root;
3604         const char *descr;
3605         int ret = -ENOMEM;
3606         int blocksize, clustersize;
3607         unsigned int db_count;
3608         unsigned int i;
3609         int needs_recovery, has_huge_files, has_bigalloc;
3610         __u64 blocks_count;
3611         int err = 0;
3612         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3613         ext4_group_t first_not_zeroed;
3614
3615         if ((data && !orig_data) || !sbi)
3616                 goto out_free_base;
3617
3618         sbi->s_daxdev = dax_dev;
3619         sbi->s_blockgroup_lock =
3620                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3621         if (!sbi->s_blockgroup_lock)
3622                 goto out_free_base;
3623
3624         sb->s_fs_info = sbi;
3625         sbi->s_sb = sb;
3626         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3627         sbi->s_sb_block = sb_block;
3628         if (sb->s_bdev->bd_part)
3629                 sbi->s_sectors_written_start =
3630                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3631
3632         /* Cleanup superblock name */
3633         strreplace(sb->s_id, '/', '!');
3634
3635         /* -EINVAL is default */
3636         ret = -EINVAL;
3637         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3638         if (!blocksize) {
3639                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3640                 goto out_fail;
3641         }
3642
3643         /*
3644          * The ext4 superblock will not be buffer aligned for other than 1kB
3645          * block sizes.  We need to calculate the offset from buffer start.
3646          */
3647         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3648                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3649                 offset = do_div(logical_sb_block, blocksize);
3650         } else {
3651                 logical_sb_block = sb_block;
3652         }
3653
3654         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3655                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3656                 goto out_fail;
3657         }
3658         /*
3659          * Note: s_es must be initialized as soon as possible because
3660          *       some ext4 macro-instructions depend on its value
3661          */
3662         es = (struct ext4_super_block *) (bh->b_data + offset);
3663         sbi->s_es = es;
3664         sb->s_magic = le16_to_cpu(es->s_magic);
3665         if (sb->s_magic != EXT4_SUPER_MAGIC)
3666                 goto cantfind_ext4;
3667         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3668
3669         /* Warn if metadata_csum and gdt_csum are both set. */
3670         if (ext4_has_feature_metadata_csum(sb) &&
3671             ext4_has_feature_gdt_csum(sb))
3672                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3673                              "redundant flags; please run fsck.");
3674
3675         /* Check for a known checksum algorithm */
3676         if (!ext4_verify_csum_type(sb, es)) {
3677                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3678                          "unknown checksum algorithm.");
3679                 silent = 1;
3680                 goto cantfind_ext4;
3681         }
3682
3683         /* Load the checksum driver */
3684         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3685         if (IS_ERR(sbi->s_chksum_driver)) {
3686                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3687                 ret = PTR_ERR(sbi->s_chksum_driver);
3688                 sbi->s_chksum_driver = NULL;
3689                 goto failed_mount;
3690         }
3691
3692         /* Check superblock checksum */
3693         if (!ext4_superblock_csum_verify(sb, es)) {
3694                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3695                          "invalid superblock checksum.  Run e2fsck?");
3696                 silent = 1;
3697                 ret = -EFSBADCRC;
3698                 goto cantfind_ext4;
3699         }
3700
3701         /* Precompute checksum seed for all metadata */
3702         if (ext4_has_feature_csum_seed(sb))
3703                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3704         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3705                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3706                                                sizeof(es->s_uuid));
3707
3708         /* Set defaults before we parse the mount options */
3709         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3710         set_opt(sb, INIT_INODE_TABLE);
3711         if (def_mount_opts & EXT4_DEFM_DEBUG)
3712                 set_opt(sb, DEBUG);
3713         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3714                 set_opt(sb, GRPID);
3715         if (def_mount_opts & EXT4_DEFM_UID16)
3716                 set_opt(sb, NO_UID32);
3717         /* xattr user namespace & acls are now defaulted on */
3718         set_opt(sb, XATTR_USER);
3719 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3720         set_opt(sb, POSIX_ACL);
3721 #endif
3722         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3723         if (ext4_has_metadata_csum(sb))
3724                 set_opt(sb, JOURNAL_CHECKSUM);
3725
3726         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3727                 set_opt(sb, JOURNAL_DATA);
3728         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3729                 set_opt(sb, ORDERED_DATA);
3730         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3731                 set_opt(sb, WRITEBACK_DATA);
3732
3733         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3734                 set_opt(sb, ERRORS_PANIC);
3735         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3736                 set_opt(sb, ERRORS_CONT);
3737         else
3738                 set_opt(sb, ERRORS_RO);
3739         /* block_validity enabled by default; disable with noblock_validity */
3740         set_opt(sb, BLOCK_VALIDITY);
3741         if (def_mount_opts & EXT4_DEFM_DISCARD)
3742                 set_opt(sb, DISCARD);
3743
3744         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3745         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3746         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3747         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3748         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3749
3750         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3751                 set_opt(sb, BARRIER);
3752
3753         /*
3754          * enable delayed allocation by default
3755          * Use -o nodelalloc to turn it off
3756          */
3757         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3758             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3759                 set_opt(sb, DELALLOC);
3760
3761         /*
3762          * set default s_li_wait_mult for lazyinit, for the case there is
3763          * no mount option specified.
3764          */
3765         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3766
3767         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3768         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3769             blocksize > EXT4_MAX_BLOCK_SIZE) {
3770                 ext4_msg(sb, KERN_ERR,
3771                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3772                          blocksize, le32_to_cpu(es->s_log_block_size));
3773                 goto failed_mount;
3774         }
3775
3776         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3777                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3778                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3779         } else {
3780                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3781                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3782                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3783                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3784                                  sbi->s_first_ino);
3785                         goto failed_mount;
3786                 }
3787                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3788                     (!is_power_of_2(sbi->s_inode_size)) ||
3789                     (sbi->s_inode_size > blocksize)) {
3790                         ext4_msg(sb, KERN_ERR,
3791                                "unsupported inode size: %d",
3792                                sbi->s_inode_size);
3793                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
3794                         goto failed_mount;
3795                 }
3796                 /*
3797                  * i_atime_extra is the last extra field available for
3798                  * [acm]times in struct ext4_inode. Checking for that
3799                  * field should suffice to ensure we have extra space
3800                  * for all three.
3801                  */
3802                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
3803                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
3804                         sb->s_time_gran = 1;
3805                 } else {
3806                         sb->s_time_gran = NSEC_PER_SEC;
3807                 }
3808         }
3809         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3810                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3811                         EXT4_GOOD_OLD_INODE_SIZE;
3812                 if (ext4_has_feature_extra_isize(sb)) {
3813                         unsigned v, max = (sbi->s_inode_size -
3814                                            EXT4_GOOD_OLD_INODE_SIZE);
3815
3816                         v = le16_to_cpu(es->s_want_extra_isize);
3817                         if (v > max) {
3818                                 ext4_msg(sb, KERN_ERR,
3819                                          "bad s_want_extra_isize: %d", v);
3820                                 goto failed_mount;
3821                         }
3822                         if (sbi->s_want_extra_isize < v)
3823                                 sbi->s_want_extra_isize = v;
3824
3825                         v = le16_to_cpu(es->s_min_extra_isize);
3826                         if (v > max) {
3827                                 ext4_msg(sb, KERN_ERR,
3828                                          "bad s_min_extra_isize: %d", v);
3829                                 goto failed_mount;
3830                         }
3831                         if (sbi->s_want_extra_isize < v)
3832                                 sbi->s_want_extra_isize = v;
3833                 }
3834         }
3835
3836         if (sbi->s_es->s_mount_opts[0]) {
3837                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3838                                               sizeof(sbi->s_es->s_mount_opts),
3839                                               GFP_KERNEL);
3840                 if (!s_mount_opts)
3841                         goto failed_mount;
3842                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3843                                    &journal_ioprio, 0)) {
3844                         ext4_msg(sb, KERN_WARNING,
3845                                  "failed to parse options in superblock: %s",
3846                                  s_mount_opts);
3847                 }
3848                 kfree(s_mount_opts);
3849         }
3850         sbi->s_def_mount_opt = sbi->s_mount_opt;
3851         if (!parse_options((char *) data, sb, &journal_devnum,
3852                            &journal_ioprio, 0))
3853                 goto failed_mount;
3854
3855         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3856                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3857                             "with data=journal disables delayed "
3858                             "allocation and O_DIRECT support!\n");
3859                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3860                         ext4_msg(sb, KERN_ERR, "can't mount with "
3861                                  "both data=journal and delalloc");
3862                         goto failed_mount;
3863                 }
3864                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3865                         ext4_msg(sb, KERN_ERR, "can't mount with "
3866                                  "both data=journal and dioread_nolock");
3867                         goto failed_mount;
3868                 }
3869                 if (test_opt(sb, DAX)) {
3870                         ext4_msg(sb, KERN_ERR, "can't mount with "
3871                                  "both data=journal and dax");
3872                         goto failed_mount;
3873                 }
3874                 if (ext4_has_feature_encrypt(sb)) {
3875                         ext4_msg(sb, KERN_WARNING,
3876                                  "encrypted files will use data=ordered "
3877                                  "instead of data journaling mode");
3878                 }
3879                 if (test_opt(sb, DELALLOC))
3880                         clear_opt(sb, DELALLOC);
3881         } else {
3882                 sb->s_iflags |= SB_I_CGROUPWB;
3883         }
3884
3885         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
3886                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
3887
3888         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3889             (ext4_has_compat_features(sb) ||
3890              ext4_has_ro_compat_features(sb) ||
3891              ext4_has_incompat_features(sb)))
3892                 ext4_msg(sb, KERN_WARNING,
3893                        "feature flags set on rev 0 fs, "
3894                        "running e2fsck is recommended");
3895
3896         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3897                 set_opt2(sb, HURD_COMPAT);
3898                 if (ext4_has_feature_64bit(sb)) {
3899                         ext4_msg(sb, KERN_ERR,
3900                                  "The Hurd can't support 64-bit file systems");
3901                         goto failed_mount;
3902                 }
3903
3904                 /*
3905                  * ea_inode feature uses l_i_version field which is not
3906                  * available in HURD_COMPAT mode.
3907                  */
3908                 if (ext4_has_feature_ea_inode(sb)) {
3909                         ext4_msg(sb, KERN_ERR,
3910                                  "ea_inode feature is not supported for Hurd");
3911                         goto failed_mount;
3912                 }
3913         }
3914
3915         if (IS_EXT2_SB(sb)) {
3916                 if (ext2_feature_set_ok(sb))
3917                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3918                                  "using the ext4 subsystem");
3919                 else {
3920                         /*
3921                          * If we're probing be silent, if this looks like
3922                          * it's actually an ext[34] filesystem.
3923                          */
3924                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3925                                 goto failed_mount;
3926                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3927                                  "to feature incompatibilities");
3928                         goto failed_mount;
3929                 }
3930         }
3931
3932         if (IS_EXT3_SB(sb)) {
3933                 if (ext3_feature_set_ok(sb))
3934                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3935                                  "using the ext4 subsystem");
3936                 else {
3937                         /*
3938                          * If we're probing be silent, if this looks like
3939                          * it's actually an ext4 filesystem.
3940                          */
3941                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3942                                 goto failed_mount;
3943                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3944                                  "to feature incompatibilities");
3945                         goto failed_mount;
3946                 }
3947         }
3948
3949         /*
3950          * Check feature flags regardless of the revision level, since we
3951          * previously didn't change the revision level when setting the flags,
3952          * so there is a chance incompat flags are set on a rev 0 filesystem.
3953          */
3954         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
3955                 goto failed_mount;
3956
3957         if (le32_to_cpu(es->s_log_block_size) >
3958             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3959                 ext4_msg(sb, KERN_ERR,
3960                          "Invalid log block size: %u",
3961                          le32_to_cpu(es->s_log_block_size));
3962                 goto failed_mount;
3963         }
3964         if (le32_to_cpu(es->s_log_cluster_size) >
3965             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3966                 ext4_msg(sb, KERN_ERR,
3967                          "Invalid log cluster size: %u",
3968                          le32_to_cpu(es->s_log_cluster_size));
3969                 goto failed_mount;
3970         }
3971
3972         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3973                 ext4_msg(sb, KERN_ERR,
3974                          "Number of reserved GDT blocks insanely large: %d",
3975                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3976                 goto failed_mount;
3977         }
3978
3979         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3980                 if (ext4_has_feature_inline_data(sb)) {
3981                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
3982                                         " that may contain inline data");
3983                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
3984                 }
3985                 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
3986                         ext4_msg(sb, KERN_ERR,
3987                                 "DAX unsupported by block device. Turning off DAX.");
3988                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
3989                 }
3990         }
3991
3992         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
3993                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3994                          es->s_encryption_level);
3995                 goto failed_mount;
3996         }
3997
3998         if (sb->s_blocksize != blocksize) {
3999                 /* Validate the filesystem blocksize */
4000                 if (!sb_set_blocksize(sb, blocksize)) {
4001                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4002                                         blocksize);
4003                         goto failed_mount;
4004                 }
4005
4006                 brelse(bh);
4007                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4008                 offset = do_div(logical_sb_block, blocksize);
4009                 bh = sb_bread_unmovable(sb, logical_sb_block);
4010                 if (!bh) {
4011                         ext4_msg(sb, KERN_ERR,
4012                                "Can't read superblock on 2nd try");
4013                         goto failed_mount;
4014                 }
4015                 es = (struct ext4_super_block *)(bh->b_data + offset);
4016                 sbi->s_es = es;
4017                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4018                         ext4_msg(sb, KERN_ERR,
4019                                "Magic mismatch, very weird!");
4020                         goto failed_mount;
4021                 }
4022         }
4023
4024         has_huge_files = ext4_has_feature_huge_file(sb);
4025         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4026                                                       has_huge_files);
4027         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4028
4029         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4030         if (ext4_has_feature_64bit(sb)) {
4031                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4032                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4033                     !is_power_of_2(sbi->s_desc_size)) {
4034                         ext4_msg(sb, KERN_ERR,
4035                                "unsupported descriptor size %lu",
4036                                sbi->s_desc_size);
4037                         goto failed_mount;
4038                 }
4039         } else
4040                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4041
4042         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4043         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4044
4045         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4046         if (sbi->s_inodes_per_block == 0)
4047                 goto cantfind_ext4;
4048         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4049             sbi->s_inodes_per_group > blocksize * 8) {
4050                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4051                          sbi->s_inodes_per_group);
4052                 goto failed_mount;
4053         }
4054         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4055                                         sbi->s_inodes_per_block;
4056         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4057         sbi->s_sbh = bh;
4058         sbi->s_mount_state = le16_to_cpu(es->s_state);
4059         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4060         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4061
4062         for (i = 0; i < 4; i++)
4063                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4064         sbi->s_def_hash_version = es->s_def_hash_version;
4065         if (ext4_has_feature_dir_index(sb)) {
4066                 i = le32_to_cpu(es->s_flags);
4067                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4068                         sbi->s_hash_unsigned = 3;
4069                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4070 #ifdef __CHAR_UNSIGNED__
4071                         if (!sb_rdonly(sb))
4072                                 es->s_flags |=
4073                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4074                         sbi->s_hash_unsigned = 3;
4075 #else
4076                         if (!sb_rdonly(sb))
4077                                 es->s_flags |=
4078                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4079 #endif
4080                 }
4081         }
4082
4083         /* Handle clustersize */
4084         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4085         has_bigalloc = ext4_has_feature_bigalloc(sb);
4086         if (has_bigalloc) {
4087                 if (clustersize < blocksize) {
4088                         ext4_msg(sb, KERN_ERR,
4089                                  "cluster size (%d) smaller than "
4090                                  "block size (%d)", clustersize, blocksize);
4091                         goto failed_mount;
4092                 }
4093                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4094                         le32_to_cpu(es->s_log_block_size);
4095                 sbi->s_clusters_per_group =
4096                         le32_to_cpu(es->s_clusters_per_group);
4097                 if (sbi->s_clusters_per_group > blocksize * 8) {
4098                         ext4_msg(sb, KERN_ERR,
4099                                  "#clusters per group too big: %lu",
4100                                  sbi->s_clusters_per_group);
4101                         goto failed_mount;
4102                 }
4103                 if (sbi->s_blocks_per_group !=
4104                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4105                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4106                                  "clusters per group (%lu) inconsistent",
4107                                  sbi->s_blocks_per_group,
4108                                  sbi->s_clusters_per_group);
4109                         goto failed_mount;
4110                 }
4111         } else {
4112                 if (clustersize != blocksize) {
4113                         ext4_msg(sb, KERN_ERR,
4114                                  "fragment/cluster size (%d) != "
4115                                  "block size (%d)", clustersize, blocksize);
4116                         goto failed_mount;
4117                 }
4118                 if (sbi->s_blocks_per_group > blocksize * 8) {
4119                         ext4_msg(sb, KERN_ERR,
4120                                  "#blocks per group too big: %lu",
4121                                  sbi->s_blocks_per_group);
4122                         goto failed_mount;
4123                 }
4124                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4125                 sbi->s_cluster_bits = 0;
4126         }
4127         sbi->s_cluster_ratio = clustersize / blocksize;
4128
4129         /* Do we have standard group size of clustersize * 8 blocks ? */
4130         if (sbi->s_blocks_per_group == clustersize << 3)
4131                 set_opt2(sb, STD_GROUP_SIZE);
4132
4133         /*
4134          * Test whether we have more sectors than will fit in sector_t,
4135          * and whether the max offset is addressable by the page cache.
4136          */
4137         err = generic_check_addressable(sb->s_blocksize_bits,
4138                                         ext4_blocks_count(es));
4139         if (err) {
4140                 ext4_msg(sb, KERN_ERR, "filesystem"
4141                          " too large to mount safely on this system");
4142                 if (sizeof(sector_t) < 8)
4143                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
4144                 goto failed_mount;
4145         }
4146
4147         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4148                 goto cantfind_ext4;
4149
4150         /* check blocks count against device size */
4151         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4152         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4153                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4154                        "exceeds size of device (%llu blocks)",
4155                        ext4_blocks_count(es), blocks_count);
4156                 goto failed_mount;
4157         }
4158
4159         /*
4160          * It makes no sense for the first data block to be beyond the end
4161          * of the filesystem.
4162          */
4163         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4164                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4165                          "block %u is beyond end of filesystem (%llu)",
4166                          le32_to_cpu(es->s_first_data_block),
4167                          ext4_blocks_count(es));
4168                 goto failed_mount;
4169         }
4170         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4171             (sbi->s_cluster_ratio == 1)) {
4172                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4173                          "block is 0 with a 1k block and cluster size");
4174                 goto failed_mount;
4175         }
4176
4177         blocks_count = (ext4_blocks_count(es) -
4178                         le32_to_cpu(es->s_first_data_block) +
4179                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4180         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4181         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4182                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4183                        "(block count %llu, first data block %u, "
4184                        "blocks per group %lu)", blocks_count,
4185                        ext4_blocks_count(es),
4186                        le32_to_cpu(es->s_first_data_block),
4187                        EXT4_BLOCKS_PER_GROUP(sb));
4188                 goto failed_mount;
4189         }
4190         sbi->s_groups_count = blocks_count;
4191         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4192                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4193         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4194             le32_to_cpu(es->s_inodes_count)) {
4195                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4196                          le32_to_cpu(es->s_inodes_count),
4197                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4198                 ret = -EINVAL;
4199                 goto failed_mount;
4200         }
4201         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4202                    EXT4_DESC_PER_BLOCK(sb);
4203         if (ext4_has_feature_meta_bg(sb)) {
4204                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4205                         ext4_msg(sb, KERN_WARNING,
4206                                  "first meta block group too large: %u "
4207                                  "(group descriptor block count %u)",
4208                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4209                         goto failed_mount;
4210                 }
4211         }
4212         rcu_assign_pointer(sbi->s_group_desc,
4213                            kvmalloc_array(db_count,
4214                                           sizeof(struct buffer_head *),
4215                                           GFP_KERNEL));
4216         if (sbi->s_group_desc == NULL) {
4217                 ext4_msg(sb, KERN_ERR, "not enough memory");
4218                 ret = -ENOMEM;
4219                 goto failed_mount;
4220         }
4221
4222         bgl_lock_init(sbi->s_blockgroup_lock);
4223
4224         /* Pre-read the descriptors into the buffer cache */
4225         for (i = 0; i < db_count; i++) {
4226                 block = descriptor_loc(sb, logical_sb_block, i);
4227                 sb_breadahead_unmovable(sb, block);
4228         }
4229
4230         for (i = 0; i < db_count; i++) {
4231                 struct buffer_head *bh;
4232
4233                 block = descriptor_loc(sb, logical_sb_block, i);
4234                 bh = sb_bread_unmovable(sb, block);
4235                 if (!bh) {
4236                         ext4_msg(sb, KERN_ERR,
4237                                "can't read group descriptor %d", i);
4238                         db_count = i;
4239                         goto failed_mount2;
4240                 }
4241                 rcu_read_lock();
4242                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4243                 rcu_read_unlock();
4244         }
4245         sbi->s_gdb_count = db_count;
4246         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4247                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4248                 ret = -EFSCORRUPTED;
4249                 goto failed_mount2;
4250         }
4251
4252         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4253
4254         /* Register extent status tree shrinker */
4255         if (ext4_es_register_shrinker(sbi))
4256                 goto failed_mount3;
4257
4258         sbi->s_stripe = ext4_get_stripe_size(sbi);
4259         sbi->s_extent_max_zeroout_kb = 32;
4260
4261         /*
4262          * set up enough so that it can read an inode
4263          */
4264         sb->s_op = &ext4_sops;
4265         sb->s_export_op = &ext4_export_ops;
4266         sb->s_xattr = ext4_xattr_handlers;
4267 #ifdef CONFIG_EXT4_FS_ENCRYPTION
4268         sb->s_cop = &ext4_cryptops;
4269 #endif
4270 #ifdef CONFIG_QUOTA
4271         sb->dq_op = &ext4_quota_operations;
4272         if (ext4_has_feature_quota(sb))
4273                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4274         else
4275                 sb->s_qcop = &ext4_qctl_operations;
4276         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4277 #endif
4278         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4279
4280         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4281         mutex_init(&sbi->s_orphan_lock);
4282
4283         sb->s_root = NULL;
4284
4285         needs_recovery = (es->s_last_orphan != 0 ||
4286                           ext4_has_feature_journal_needs_recovery(sb));
4287
4288         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4289                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4290                         goto failed_mount3a;
4291
4292         /*
4293          * The first inode we look at is the journal inode.  Don't try
4294          * root first: it may be modified in the journal!
4295          */
4296         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4297                 err = ext4_load_journal(sb, es, journal_devnum);
4298                 if (err)
4299                         goto failed_mount3a;
4300         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4301                    ext4_has_feature_journal_needs_recovery(sb)) {
4302                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4303                        "suppressed and not mounted read-only");
4304                 goto failed_mount3a;
4305         } else {
4306                 /* Nojournal mode, all journal mount options are illegal */
4307                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4308                         ext4_msg(sb, KERN_ERR, "can't mount with "
4309                                  "journal_async_commit, fs mounted w/o journal");
4310                         goto failed_mount3a;
4311                 }
4312
4313                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4314                         ext4_msg(sb, KERN_ERR, "can't mount with "
4315                                  "journal_checksum, fs mounted w/o journal");
4316                         goto failed_mount3a;
4317                 }
4318                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4319                         ext4_msg(sb, KERN_ERR, "can't mount with "
4320                                  "commit=%lu, fs mounted w/o journal",
4321                                  sbi->s_commit_interval / HZ);
4322                         goto failed_mount3a;
4323                 }
4324                 if (EXT4_MOUNT_DATA_FLAGS &
4325                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4326                         ext4_msg(sb, KERN_ERR, "can't mount with "
4327                                  "data=, fs mounted w/o journal");
4328                         goto failed_mount3a;
4329                 }
4330                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4331                 clear_opt(sb, JOURNAL_CHECKSUM);
4332                 clear_opt(sb, DATA_FLAGS);
4333                 sbi->s_journal = NULL;
4334                 needs_recovery = 0;
4335                 goto no_journal;
4336         }
4337
4338         if (ext4_has_feature_64bit(sb) &&
4339             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4340                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4341                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4342                 goto failed_mount_wq;
4343         }
4344
4345         if (!set_journal_csum_feature_set(sb)) {
4346                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4347                          "feature set");
4348                 goto failed_mount_wq;
4349         }
4350
4351         /* We have now updated the journal if required, so we can
4352          * validate the data journaling mode. */
4353         switch (test_opt(sb, DATA_FLAGS)) {
4354         case 0:
4355                 /* No mode set, assume a default based on the journal
4356                  * capabilities: ORDERED_DATA if the journal can
4357                  * cope, else JOURNAL_DATA
4358                  */
4359                 if (jbd2_journal_check_available_features
4360                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4361                         set_opt(sb, ORDERED_DATA);
4362                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4363                 } else {
4364                         set_opt(sb, JOURNAL_DATA);
4365                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4366                 }
4367                 break;
4368
4369         case EXT4_MOUNT_ORDERED_DATA:
4370         case EXT4_MOUNT_WRITEBACK_DATA:
4371                 if (!jbd2_journal_check_available_features
4372                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4373                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4374                                "requested data journaling mode");
4375                         goto failed_mount_wq;
4376                 }
4377         default:
4378                 break;
4379         }
4380
4381         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4382             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4383                 ext4_msg(sb, KERN_ERR, "can't mount with "
4384                         "journal_async_commit in data=ordered mode");
4385                 goto failed_mount_wq;
4386         }
4387
4388         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4389
4390         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4391
4392 no_journal:
4393         if (!test_opt(sb, NO_MBCACHE)) {
4394                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4395                 if (!sbi->s_ea_block_cache) {
4396                         ext4_msg(sb, KERN_ERR,
4397                                  "Failed to create ea_block_cache");
4398                         goto failed_mount_wq;
4399                 }
4400
4401                 if (ext4_has_feature_ea_inode(sb)) {
4402                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4403                         if (!sbi->s_ea_inode_cache) {
4404                                 ext4_msg(sb, KERN_ERR,
4405                                          "Failed to create ea_inode_cache");
4406                                 goto failed_mount_wq;
4407                         }
4408                 }
4409         }
4410
4411         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
4412             (blocksize != PAGE_SIZE)) {
4413                 ext4_msg(sb, KERN_ERR,
4414                          "Unsupported blocksize for fs encryption");
4415                 goto failed_mount_wq;
4416         }
4417
4418         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4419             !ext4_has_feature_encrypt(sb)) {
4420                 ext4_set_feature_encrypt(sb);
4421                 ext4_commit_super(sb, 1);
4422         }
4423
4424         /*
4425          * Get the # of file system overhead blocks from the
4426          * superblock if present.
4427          */
4428         sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4429         /* ignore the precalculated value if it is ridiculous */
4430         if (sbi->s_overhead > ext4_blocks_count(es))
4431                 sbi->s_overhead = 0;
4432         /*
4433          * If the bigalloc feature is not enabled recalculating the
4434          * overhead doesn't take long, so we might as well just redo
4435          * it to make sure we are using the correct value.
4436          */
4437         if (!ext4_has_feature_bigalloc(sb))
4438                 sbi->s_overhead = 0;
4439         if (sbi->s_overhead == 0) {
4440                 err = ext4_calculate_overhead(sb);
4441                 if (err)
4442                         goto failed_mount_wq;
4443         }
4444
4445         /*
4446          * The maximum number of concurrent works can be high and
4447          * concurrency isn't really necessary.  Limit it to 1.
4448          */
4449         EXT4_SB(sb)->rsv_conversion_wq =
4450                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4451         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4452                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4453                 ret = -ENOMEM;
4454                 goto failed_mount4;
4455         }
4456
4457         /*
4458          * The jbd2_journal_load will have done any necessary log recovery,
4459          * so we can safely mount the rest of the filesystem now.
4460          */
4461
4462         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4463         if (IS_ERR(root)) {
4464                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4465                 ret = PTR_ERR(root);
4466                 root = NULL;
4467                 goto failed_mount4;
4468         }
4469         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4470                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4471                 iput(root);
4472                 goto failed_mount4;
4473         }
4474         sb->s_root = d_make_root(root);
4475         if (!sb->s_root) {
4476                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4477                 ret = -ENOMEM;
4478                 goto failed_mount4;
4479         }
4480
4481         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4482         if (ret == -EROFS) {
4483                 sb->s_flags |= SB_RDONLY;
4484                 ret = 0;
4485         } else if (ret)
4486                 goto failed_mount4a;
4487
4488         ext4_set_resv_clusters(sb);
4489
4490         if (test_opt(sb, BLOCK_VALIDITY)) {
4491                 err = ext4_setup_system_zone(sb);
4492                 if (err) {
4493                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
4494                                  "zone (%d)", err);
4495                         goto failed_mount4a;
4496                 }
4497         }
4498
4499         ext4_ext_init(sb);
4500         err = ext4_mb_init(sb);
4501         if (err) {
4502                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4503                          err);
4504                 goto failed_mount5;
4505         }
4506
4507         block = ext4_count_free_clusters(sb);
4508         ext4_free_blocks_count_set(sbi->s_es,
4509                                    EXT4_C2B(sbi, block));
4510         ext4_superblock_csum_set(sb);
4511         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4512                                   GFP_KERNEL);
4513         if (!err) {
4514                 unsigned long freei = ext4_count_free_inodes(sb);
4515                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4516                 ext4_superblock_csum_set(sb);
4517                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4518                                           GFP_KERNEL);
4519         }
4520         if (!err)
4521                 err = percpu_counter_init(&sbi->s_dirs_counter,
4522                                           ext4_count_dirs(sb), GFP_KERNEL);
4523         if (!err)
4524                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4525                                           GFP_KERNEL);
4526         if (!err)
4527                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4528
4529         if (err) {
4530                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4531                 goto failed_mount6;
4532         }
4533
4534         if (ext4_has_feature_flex_bg(sb))
4535                 if (!ext4_fill_flex_info(sb)) {
4536                         ext4_msg(sb, KERN_ERR,
4537                                "unable to initialize "
4538                                "flex_bg meta info!");
4539                         ret = -ENOMEM;
4540                         goto failed_mount6;
4541                 }
4542
4543         err = ext4_register_li_request(sb, first_not_zeroed);
4544         if (err)
4545                 goto failed_mount6;
4546
4547         err = ext4_register_sysfs(sb);
4548         if (err)
4549                 goto failed_mount7;
4550
4551 #ifdef CONFIG_QUOTA
4552         /* Enable quota usage during mount. */
4553         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4554                 err = ext4_enable_quotas(sb);
4555                 if (err)
4556                         goto failed_mount8;
4557         }
4558 #endif  /* CONFIG_QUOTA */
4559
4560         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4561         ext4_orphan_cleanup(sb, es);
4562         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4563         if (needs_recovery) {
4564                 ext4_msg(sb, KERN_INFO, "recovery complete");
4565                 err = ext4_mark_recovery_complete(sb, es);
4566                 if (err)
4567                         goto failed_mount8;
4568         }
4569         if (EXT4_SB(sb)->s_journal) {
4570                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4571                         descr = " journalled data mode";
4572                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4573                         descr = " ordered data mode";
4574                 else
4575                         descr = " writeback data mode";
4576         } else
4577                 descr = "out journal";
4578
4579         if (test_opt(sb, DISCARD)) {
4580                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4581                 if (!blk_queue_discard(q))
4582                         ext4_msg(sb, KERN_WARNING,
4583                                  "mounting with \"discard\" option, but "
4584                                  "the device does not support discard");
4585         }
4586
4587         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4588                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4589                          "Opts: %.*s%s%s", descr,
4590                          (int) sizeof(sbi->s_es->s_mount_opts),
4591                          sbi->s_es->s_mount_opts,
4592                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4593
4594         if (es->s_error_count)
4595                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4596
4597         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4598         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4599         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4600         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4601
4602         kfree(orig_data);
4603         return 0;
4604
4605 cantfind_ext4:
4606         if (!silent)
4607                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4608         goto failed_mount;
4609
4610 failed_mount8:
4611         ext4_unregister_sysfs(sb);
4612         kobject_put(&sbi->s_kobj);
4613 failed_mount7:
4614         ext4_unregister_li_request(sb);
4615 failed_mount6:
4616         ext4_mb_release(sb);
4617         rcu_read_lock();
4618         flex_groups = rcu_dereference(sbi->s_flex_groups);
4619         if (flex_groups) {
4620                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
4621                         kvfree(flex_groups[i]);
4622                 kvfree(flex_groups);
4623         }
4624         rcu_read_unlock();
4625         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4626         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4627         percpu_counter_destroy(&sbi->s_dirs_counter);
4628         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4629         percpu_free_rwsem(&sbi->s_writepages_rwsem);
4630 failed_mount5:
4631         ext4_ext_release(sb);
4632         ext4_release_system_zone(sb);
4633 failed_mount4a:
4634         dput(sb->s_root);
4635         sb->s_root = NULL;
4636 failed_mount4:
4637         ext4_msg(sb, KERN_ERR, "mount failed");
4638         if (EXT4_SB(sb)->rsv_conversion_wq)
4639                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4640 failed_mount_wq:
4641         if (sbi->s_ea_inode_cache) {
4642                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4643                 sbi->s_ea_inode_cache = NULL;
4644         }
4645         if (sbi->s_ea_block_cache) {
4646                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4647                 sbi->s_ea_block_cache = NULL;
4648         }
4649         if (sbi->s_journal) {
4650                 jbd2_journal_destroy(sbi->s_journal);
4651                 sbi->s_journal = NULL;
4652         }
4653 failed_mount3a:
4654         ext4_es_unregister_shrinker(sbi);
4655 failed_mount3:
4656         del_timer_sync(&sbi->s_err_report);
4657         if (sbi->s_mmp_tsk)
4658                 kthread_stop(sbi->s_mmp_tsk);
4659 failed_mount2:
4660         rcu_read_lock();
4661         group_desc = rcu_dereference(sbi->s_group_desc);
4662         for (i = 0; i < db_count; i++)
4663                 brelse(group_desc[i]);
4664         kvfree(group_desc);
4665         rcu_read_unlock();
4666 failed_mount:
4667         if (sbi->s_chksum_driver)
4668                 crypto_free_shash(sbi->s_chksum_driver);
4669 #ifdef CONFIG_QUOTA
4670         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4671                 kfree(sbi->s_qf_names[i]);
4672 #endif
4673         ext4_blkdev_remove(sbi);
4674         brelse(bh);
4675 out_fail:
4676         sb->s_fs_info = NULL;
4677         kfree(sbi->s_blockgroup_lock);
4678 out_free_base:
4679         kfree(sbi);
4680         kfree(orig_data);
4681         fs_put_dax(dax_dev);
4682         return err ? err : ret;
4683 }
4684
4685 /*
4686  * Setup any per-fs journal parameters now.  We'll do this both on
4687  * initial mount, once the journal has been initialised but before we've
4688  * done any recovery; and again on any subsequent remount.
4689  */
4690 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4691 {
4692         struct ext4_sb_info *sbi = EXT4_SB(sb);
4693
4694         journal->j_commit_interval = sbi->s_commit_interval;
4695         journal->j_min_batch_time = sbi->s_min_batch_time;
4696         journal->j_max_batch_time = sbi->s_max_batch_time;
4697
4698         write_lock(&journal->j_state_lock);
4699         if (test_opt(sb, BARRIER))
4700                 journal->j_flags |= JBD2_BARRIER;
4701         else
4702                 journal->j_flags &= ~JBD2_BARRIER;
4703         if (test_opt(sb, DATA_ERR_ABORT))
4704                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4705         else
4706                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4707         write_unlock(&journal->j_state_lock);
4708 }
4709
4710 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4711                                              unsigned int journal_inum)
4712 {
4713         struct inode *journal_inode;
4714
4715         /*
4716          * Test for the existence of a valid inode on disk.  Bad things
4717          * happen if we iget() an unused inode, as the subsequent iput()
4718          * will try to delete it.
4719          */
4720         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4721         if (IS_ERR(journal_inode)) {
4722                 ext4_msg(sb, KERN_ERR, "no journal found");
4723                 return NULL;
4724         }
4725         if (!journal_inode->i_nlink) {
4726                 make_bad_inode(journal_inode);
4727                 iput(journal_inode);
4728                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4729                 return NULL;
4730         }
4731
4732         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4733                   journal_inode, journal_inode->i_size);
4734         if (!S_ISREG(journal_inode->i_mode) || IS_ENCRYPTED(journal_inode)) {
4735                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4736                 iput(journal_inode);
4737                 return NULL;
4738         }
4739         return journal_inode;
4740 }
4741
4742 static journal_t *ext4_get_journal(struct super_block *sb,
4743                                    unsigned int journal_inum)
4744 {
4745         struct inode *journal_inode;
4746         journal_t *journal;
4747
4748         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
4749                 return NULL;
4750
4751         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4752         if (!journal_inode)
4753                 return NULL;
4754
4755         journal = jbd2_journal_init_inode(journal_inode);
4756         if (!journal) {
4757                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4758                 iput(journal_inode);
4759                 return NULL;
4760         }
4761         journal->j_private = sb;
4762         ext4_init_journal_params(sb, journal);
4763         return journal;
4764 }
4765
4766 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4767                                        dev_t j_dev)
4768 {
4769         struct buffer_head *bh;
4770         journal_t *journal;
4771         ext4_fsblk_t start;
4772         ext4_fsblk_t len;
4773         int hblock, blocksize;
4774         ext4_fsblk_t sb_block;
4775         unsigned long offset;
4776         struct ext4_super_block *es;
4777         struct block_device *bdev;
4778
4779         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
4780                 return NULL;
4781
4782         bdev = ext4_blkdev_get(j_dev, sb);
4783         if (bdev == NULL)
4784                 return NULL;
4785
4786         blocksize = sb->s_blocksize;
4787         hblock = bdev_logical_block_size(bdev);
4788         if (blocksize < hblock) {
4789                 ext4_msg(sb, KERN_ERR,
4790                         "blocksize too small for journal device");
4791                 goto out_bdev;
4792         }
4793
4794         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4795         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4796         set_blocksize(bdev, blocksize);
4797         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4798                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4799                        "external journal");
4800                 goto out_bdev;
4801         }
4802
4803         es = (struct ext4_super_block *) (bh->b_data + offset);
4804         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4805             !(le32_to_cpu(es->s_feature_incompat) &
4806               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4807                 ext4_msg(sb, KERN_ERR, "external journal has "
4808                                         "bad superblock");
4809                 brelse(bh);
4810                 goto out_bdev;
4811         }
4812
4813         if ((le32_to_cpu(es->s_feature_ro_compat) &
4814              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4815             es->s_checksum != ext4_superblock_csum(sb, es)) {
4816                 ext4_msg(sb, KERN_ERR, "external journal has "
4817                                        "corrupt superblock");
4818                 brelse(bh);
4819                 goto out_bdev;
4820         }
4821
4822         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4823                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4824                 brelse(bh);
4825                 goto out_bdev;
4826         }
4827
4828         len = ext4_blocks_count(es);
4829         start = sb_block + 1;
4830         brelse(bh);     /* we're done with the superblock */
4831
4832         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4833                                         start, len, blocksize);
4834         if (!journal) {
4835                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4836                 goto out_bdev;
4837         }
4838         journal->j_private = sb;
4839         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4840         wait_on_buffer(journal->j_sb_buffer);
4841         if (!buffer_uptodate(journal->j_sb_buffer)) {
4842                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4843                 goto out_journal;
4844         }
4845         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4846                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4847                                         "user (unsupported) - %d",
4848                         be32_to_cpu(journal->j_superblock->s_nr_users));
4849                 goto out_journal;
4850         }
4851         EXT4_SB(sb)->journal_bdev = bdev;
4852         ext4_init_journal_params(sb, journal);
4853         return journal;
4854
4855 out_journal:
4856         jbd2_journal_destroy(journal);
4857 out_bdev:
4858         ext4_blkdev_put(bdev);
4859         return NULL;
4860 }
4861
4862 static int ext4_load_journal(struct super_block *sb,
4863                              struct ext4_super_block *es,
4864                              unsigned long journal_devnum)
4865 {
4866         journal_t *journal;
4867         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4868         dev_t journal_dev;
4869         int err = 0;
4870         int really_read_only;
4871         int journal_dev_ro;
4872
4873         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
4874                 return -EFSCORRUPTED;
4875
4876         if (journal_devnum &&
4877             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4878                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4879                         "numbers have changed");
4880                 journal_dev = new_decode_dev(journal_devnum);
4881         } else
4882                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4883
4884         if (journal_inum && journal_dev) {
4885                 ext4_msg(sb, KERN_ERR,
4886                          "filesystem has both journal inode and journal device!");
4887                 return -EINVAL;
4888         }
4889
4890         if (journal_inum) {
4891                 journal = ext4_get_journal(sb, journal_inum);
4892                 if (!journal)
4893                         return -EINVAL;
4894         } else {
4895                 journal = ext4_get_dev_journal(sb, journal_dev);
4896                 if (!journal)
4897                         return -EINVAL;
4898         }
4899
4900         journal_dev_ro = bdev_read_only(journal->j_dev);
4901         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
4902
4903         if (journal_dev_ro && !sb_rdonly(sb)) {
4904                 ext4_msg(sb, KERN_ERR,
4905                          "journal device read-only, try mounting with '-o ro'");
4906                 err = -EROFS;
4907                 goto err_out;
4908         }
4909
4910         /*
4911          * Are we loading a blank journal or performing recovery after a
4912          * crash?  For recovery, we need to check in advance whether we
4913          * can get read-write access to the device.
4914          */
4915         if (ext4_has_feature_journal_needs_recovery(sb)) {
4916                 if (sb_rdonly(sb)) {
4917                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4918                                         "required on readonly filesystem");
4919                         if (really_read_only) {
4920                                 ext4_msg(sb, KERN_ERR, "write access "
4921                                         "unavailable, cannot proceed "
4922                                         "(try mounting with noload)");
4923                                 err = -EROFS;
4924                                 goto err_out;
4925                         }
4926                         ext4_msg(sb, KERN_INFO, "write access will "
4927                                "be enabled during recovery");
4928                 }
4929         }
4930
4931         if (!(journal->j_flags & JBD2_BARRIER))
4932                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4933
4934         if (!ext4_has_feature_journal_needs_recovery(sb))
4935                 err = jbd2_journal_wipe(journal, !really_read_only);
4936         if (!err) {
4937                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4938                 if (save)
4939                         memcpy(save, ((char *) es) +
4940                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4941                 err = jbd2_journal_load(journal);
4942                 if (save)
4943                         memcpy(((char *) es) + EXT4_S_ERR_START,
4944                                save, EXT4_S_ERR_LEN);
4945                 kfree(save);
4946         }
4947
4948         if (err) {
4949                 ext4_msg(sb, KERN_ERR, "error loading journal");
4950                 goto err_out;
4951         }
4952
4953         EXT4_SB(sb)->s_journal = journal;
4954         err = ext4_clear_journal_err(sb, es);
4955         if (err) {
4956                 EXT4_SB(sb)->s_journal = NULL;
4957                 jbd2_journal_destroy(journal);
4958                 return err;
4959         }
4960
4961         if (!really_read_only && journal_devnum &&
4962             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4963                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4964
4965                 /* Make sure we flush the recovery flag to disk. */
4966                 ext4_commit_super(sb, 1);
4967         }
4968
4969         return 0;
4970
4971 err_out:
4972         jbd2_journal_destroy(journal);
4973         return err;
4974 }
4975
4976 static int ext4_commit_super(struct super_block *sb, int sync)
4977 {
4978         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4979         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4980         int error = 0;
4981
4982         if (!sbh)
4983                 return -EINVAL;
4984         if (block_device_ejected(sb))
4985                 return -ENODEV;
4986
4987         /*
4988          * If the file system is mounted read-only, don't update the
4989          * superblock write time.  This avoids updating the superblock
4990          * write time when we are mounting the root file system
4991          * read/only but we need to replay the journal; at that point,
4992          * for people who are east of GMT and who make their clock
4993          * tick in localtime for Windows bug-for-bug compatibility,
4994          * the clock is set in the future, and this will cause e2fsck
4995          * to complain and force a full file system check.
4996          */
4997         if (!(sb->s_flags & SB_RDONLY))
4998                 ext4_update_tstamp(es, s_wtime);
4999         if (sb->s_bdev->bd_part)
5000                 es->s_kbytes_written =
5001                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5002                             ((part_stat_read(sb->s_bdev->bd_part,
5003                                              sectors[STAT_WRITE]) -
5004                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5005         else
5006                 es->s_kbytes_written =
5007                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5008         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5009                 ext4_free_blocks_count_set(es,
5010                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5011                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5012         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5013                 es->s_free_inodes_count =
5014                         cpu_to_le32(percpu_counter_sum_positive(
5015                                 &EXT4_SB(sb)->s_freeinodes_counter));
5016         BUFFER_TRACE(sbh, "marking dirty");
5017         ext4_superblock_csum_set(sb);
5018         if (sync)
5019                 lock_buffer(sbh);
5020         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5021                 /*
5022                  * Oh, dear.  A previous attempt to write the
5023                  * superblock failed.  This could happen because the
5024                  * USB device was yanked out.  Or it could happen to
5025                  * be a transient write error and maybe the block will
5026                  * be remapped.  Nothing we can do but to retry the
5027                  * write and hope for the best.
5028                  */
5029                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5030                        "superblock detected");
5031                 clear_buffer_write_io_error(sbh);
5032                 set_buffer_uptodate(sbh);
5033         }
5034         mark_buffer_dirty(sbh);
5035         if (sync) {
5036                 unlock_buffer(sbh);
5037                 error = __sync_dirty_buffer(sbh,
5038                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5039                 if (buffer_write_io_error(sbh)) {
5040                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5041                                "superblock");
5042                         clear_buffer_write_io_error(sbh);
5043                         set_buffer_uptodate(sbh);
5044                 }
5045         }
5046         return error;
5047 }
5048
5049 /*
5050  * Have we just finished recovery?  If so, and if we are mounting (or
5051  * remounting) the filesystem readonly, then we will end up with a
5052  * consistent fs on disk.  Record that fact.
5053  */
5054 static int ext4_mark_recovery_complete(struct super_block *sb,
5055                                        struct ext4_super_block *es)
5056 {
5057         int err;
5058         journal_t *journal = EXT4_SB(sb)->s_journal;
5059
5060         if (!ext4_has_feature_journal(sb)) {
5061                 if (journal != NULL) {
5062                         ext4_error(sb, "Journal got removed while the fs was "
5063                                    "mounted!");
5064                         return -EFSCORRUPTED;
5065                 }
5066                 return 0;
5067         }
5068         jbd2_journal_lock_updates(journal);
5069         err = jbd2_journal_flush(journal);
5070         if (err < 0)
5071                 goto out;
5072
5073         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5074                 ext4_clear_feature_journal_needs_recovery(sb);
5075                 ext4_commit_super(sb, 1);
5076         }
5077 out:
5078         jbd2_journal_unlock_updates(journal);
5079         return err;
5080 }
5081
5082 /*
5083  * If we are mounting (or read-write remounting) a filesystem whose journal
5084  * has recorded an error from a previous lifetime, move that error to the
5085  * main filesystem now.
5086  */
5087 static int ext4_clear_journal_err(struct super_block *sb,
5088                                    struct ext4_super_block *es)
5089 {
5090         journal_t *journal;
5091         int j_errno;
5092         const char *errstr;
5093
5094         if (!ext4_has_feature_journal(sb)) {
5095                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5096                 return -EFSCORRUPTED;
5097         }
5098
5099         journal = EXT4_SB(sb)->s_journal;
5100
5101         /*
5102          * Now check for any error status which may have been recorded in the
5103          * journal by a prior ext4_error() or ext4_abort()
5104          */
5105
5106         j_errno = jbd2_journal_errno(journal);
5107         if (j_errno) {
5108                 char nbuf[16];
5109
5110                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5111                 ext4_warning(sb, "Filesystem error recorded "
5112                              "from previous mount: %s", errstr);
5113                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5114
5115                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5116                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5117                 ext4_commit_super(sb, 1);
5118
5119                 jbd2_journal_clear_err(journal);
5120                 jbd2_journal_update_sb_errno(journal);
5121         }
5122         return 0;
5123 }
5124
5125 /*
5126  * Force the running and committing transactions to commit,
5127  * and wait on the commit.
5128  */
5129 int ext4_force_commit(struct super_block *sb)
5130 {
5131         journal_t *journal;
5132
5133         if (sb_rdonly(sb))
5134                 return 0;
5135
5136         journal = EXT4_SB(sb)->s_journal;
5137         return ext4_journal_force_commit(journal);
5138 }
5139
5140 static int ext4_sync_fs(struct super_block *sb, int wait)
5141 {
5142         int ret = 0;
5143         tid_t target;
5144         bool needs_barrier = false;
5145         struct ext4_sb_info *sbi = EXT4_SB(sb);
5146
5147         if (unlikely(ext4_forced_shutdown(sbi)))
5148                 return 0;
5149
5150         trace_ext4_sync_fs(sb, wait);
5151         flush_workqueue(sbi->rsv_conversion_wq);
5152         /*
5153          * Writeback quota in non-journalled quota case - journalled quota has
5154          * no dirty dquots
5155          */
5156         dquot_writeback_dquots(sb, -1);
5157         /*
5158          * Data writeback is possible w/o journal transaction, so barrier must
5159          * being sent at the end of the function. But we can skip it if
5160          * transaction_commit will do it for us.
5161          */
5162         if (sbi->s_journal) {
5163                 target = jbd2_get_latest_transaction(sbi->s_journal);
5164                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5165                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5166                         needs_barrier = true;
5167
5168                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5169                         if (wait)
5170                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5171                                                            target);
5172                 }
5173         } else if (wait && test_opt(sb, BARRIER))
5174                 needs_barrier = true;
5175         if (needs_barrier) {
5176                 int err;
5177                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
5178                 if (!ret)
5179                         ret = err;
5180         }
5181
5182         return ret;
5183 }
5184
5185 /*
5186  * LVM calls this function before a (read-only) snapshot is created.  This
5187  * gives us a chance to flush the journal completely and mark the fs clean.
5188  *
5189  * Note that only this function cannot bring a filesystem to be in a clean
5190  * state independently. It relies on upper layer to stop all data & metadata
5191  * modifications.
5192  */
5193 static int ext4_freeze(struct super_block *sb)
5194 {
5195         int error = 0;
5196         journal_t *journal;
5197
5198         if (sb_rdonly(sb))
5199                 return 0;
5200
5201         journal = EXT4_SB(sb)->s_journal;
5202
5203         if (journal) {
5204                 /* Now we set up the journal barrier. */
5205                 jbd2_journal_lock_updates(journal);
5206
5207                 /*
5208                  * Don't clear the needs_recovery flag if we failed to
5209                  * flush the journal.
5210                  */
5211                 error = jbd2_journal_flush(journal);
5212                 if (error < 0)
5213                         goto out;
5214
5215                 /* Journal blocked and flushed, clear needs_recovery flag. */
5216                 ext4_clear_feature_journal_needs_recovery(sb);
5217         }
5218
5219         error = ext4_commit_super(sb, 1);
5220 out:
5221         if (journal)
5222                 /* we rely on upper layer to stop further updates */
5223                 jbd2_journal_unlock_updates(journal);
5224         return error;
5225 }
5226
5227 /*
5228  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5229  * flag here, even though the filesystem is not technically dirty yet.
5230  */
5231 static int ext4_unfreeze(struct super_block *sb)
5232 {
5233         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5234                 return 0;
5235
5236         if (EXT4_SB(sb)->s_journal) {
5237                 /* Reset the needs_recovery flag before the fs is unlocked. */
5238                 ext4_set_feature_journal_needs_recovery(sb);
5239         }
5240
5241         ext4_commit_super(sb, 1);
5242         return 0;
5243 }
5244
5245 /*
5246  * Structure to save mount options for ext4_remount's benefit
5247  */
5248 struct ext4_mount_options {
5249         unsigned long s_mount_opt;
5250         unsigned long s_mount_opt2;
5251         kuid_t s_resuid;
5252         kgid_t s_resgid;
5253         unsigned long s_commit_interval;
5254         u32 s_min_batch_time, s_max_batch_time;
5255 #ifdef CONFIG_QUOTA
5256         int s_jquota_fmt;
5257         char *s_qf_names[EXT4_MAXQUOTAS];
5258 #endif
5259 };
5260
5261 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5262 {
5263         struct ext4_super_block *es;
5264         struct ext4_sb_info *sbi = EXT4_SB(sb);
5265         unsigned long old_sb_flags, vfs_flags;
5266         struct ext4_mount_options old_opts;
5267         int enable_quota = 0;
5268         ext4_group_t g;
5269         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5270         int err = 0;
5271 #ifdef CONFIG_QUOTA
5272         int i, j;
5273         char *to_free[EXT4_MAXQUOTAS];
5274 #endif
5275         char *orig_data = kstrdup(data, GFP_KERNEL);
5276
5277         if (data && !orig_data)
5278                 return -ENOMEM;
5279
5280         /* Store the original options */
5281         old_sb_flags = sb->s_flags;
5282         old_opts.s_mount_opt = sbi->s_mount_opt;
5283         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5284         old_opts.s_resuid = sbi->s_resuid;
5285         old_opts.s_resgid = sbi->s_resgid;
5286         old_opts.s_commit_interval = sbi->s_commit_interval;
5287         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5288         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5289 #ifdef CONFIG_QUOTA
5290         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5291         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5292                 if (sbi->s_qf_names[i]) {
5293                         char *qf_name = get_qf_name(sb, sbi, i);
5294
5295                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5296                         if (!old_opts.s_qf_names[i]) {
5297                                 for (j = 0; j < i; j++)
5298                                         kfree(old_opts.s_qf_names[j]);
5299                                 kfree(orig_data);
5300                                 return -ENOMEM;
5301                         }
5302                 } else
5303                         old_opts.s_qf_names[i] = NULL;
5304 #endif
5305         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5306                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5307
5308         /*
5309          * Some options can be enabled by ext4 and/or by VFS mount flag
5310          * either way we need to make sure it matches in both *flags and
5311          * s_flags. Copy those selected flags from *flags to s_flags
5312          */
5313         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5314         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5315
5316         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5317                 err = -EINVAL;
5318                 goto restore_opts;
5319         }
5320
5321         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5322             test_opt(sb, JOURNAL_CHECKSUM)) {
5323                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5324                          "during remount not supported; ignoring");
5325                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5326         }
5327
5328         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5329                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5330                         ext4_msg(sb, KERN_ERR, "can't mount with "
5331                                  "both data=journal and delalloc");
5332                         err = -EINVAL;
5333                         goto restore_opts;
5334                 }
5335                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5336                         ext4_msg(sb, KERN_ERR, "can't mount with "
5337                                  "both data=journal and dioread_nolock");
5338                         err = -EINVAL;
5339                         goto restore_opts;
5340                 }
5341         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5342                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5343                         ext4_msg(sb, KERN_ERR, "can't mount with "
5344                                 "journal_async_commit in data=ordered mode");
5345                         err = -EINVAL;
5346                         goto restore_opts;
5347                 }
5348         }
5349
5350         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5351                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5352                 err = -EINVAL;
5353                 goto restore_opts;
5354         }
5355
5356         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5357                 ext4_abort(sb, "Abort forced by user");
5358
5359         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5360                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5361
5362         es = sbi->s_es;
5363
5364         if (sbi->s_journal) {
5365                 ext4_init_journal_params(sb, sbi->s_journal);
5366                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5367         }
5368
5369         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5370                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5371                         err = -EROFS;
5372                         goto restore_opts;
5373                 }
5374
5375                 if (*flags & SB_RDONLY) {
5376                         err = sync_filesystem(sb);
5377                         if (err < 0)
5378                                 goto restore_opts;
5379                         err = dquot_suspend(sb, -1);
5380                         if (err < 0)
5381                                 goto restore_opts;
5382
5383                         /*
5384                          * First of all, the unconditional stuff we have to do
5385                          * to disable replay of the journal when we next remount
5386                          */
5387                         sb->s_flags |= SB_RDONLY;
5388
5389                         /*
5390                          * OK, test if we are remounting a valid rw partition
5391                          * readonly, and if so set the rdonly flag and then
5392                          * mark the partition as valid again.
5393                          */
5394                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5395                             (sbi->s_mount_state & EXT4_VALID_FS))
5396                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5397
5398                         if (sbi->s_journal) {
5399                                 /*
5400                                  * We let remount-ro finish even if marking fs
5401                                  * as clean failed...
5402                                  */
5403                                 ext4_mark_recovery_complete(sb, es);
5404                         }
5405                         if (sbi->s_mmp_tsk)
5406                                 kthread_stop(sbi->s_mmp_tsk);
5407                 } else {
5408                         /* Make sure we can mount this feature set readwrite */
5409                         if (ext4_has_feature_readonly(sb) ||
5410                             !ext4_feature_set_ok(sb, 0)) {
5411                                 err = -EROFS;
5412                                 goto restore_opts;
5413                         }
5414                         /*
5415                          * Make sure the group descriptor checksums
5416                          * are sane.  If they aren't, refuse to remount r/w.
5417                          */
5418                         for (g = 0; g < sbi->s_groups_count; g++) {
5419                                 struct ext4_group_desc *gdp =
5420                                         ext4_get_group_desc(sb, g, NULL);
5421
5422                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5423                                         ext4_msg(sb, KERN_ERR,
5424                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5425                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5426                                                le16_to_cpu(gdp->bg_checksum));
5427                                         err = -EFSBADCRC;
5428                                         goto restore_opts;
5429                                 }
5430                         }
5431
5432                         /*
5433                          * If we have an unprocessed orphan list hanging
5434                          * around from a previously readonly bdev mount,
5435                          * require a full umount/remount for now.
5436                          */
5437                         if (es->s_last_orphan) {
5438                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5439                                        "remount RDWR because of unprocessed "
5440                                        "orphan inode list.  Please "
5441                                        "umount/remount instead");
5442                                 err = -EINVAL;
5443                                 goto restore_opts;
5444                         }
5445
5446                         /*
5447                          * Mounting a RDONLY partition read-write, so reread
5448                          * and store the current valid flag.  (It may have
5449                          * been changed by e2fsck since we originally mounted
5450                          * the partition.)
5451                          */
5452                         if (sbi->s_journal) {
5453                                 err = ext4_clear_journal_err(sb, es);
5454                                 if (err)
5455                                         goto restore_opts;
5456                         }
5457                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5458
5459                         err = ext4_setup_super(sb, es, 0);
5460                         if (err)
5461                                 goto restore_opts;
5462
5463                         sb->s_flags &= ~SB_RDONLY;
5464                         if (ext4_has_feature_mmp(sb))
5465                                 if (ext4_multi_mount_protect(sb,
5466                                                 le64_to_cpu(es->s_mmp_block))) {
5467                                         err = -EROFS;
5468                                         goto restore_opts;
5469                                 }
5470                         enable_quota = 1;
5471                 }
5472         }
5473
5474         /*
5475          * Reinitialize lazy itable initialization thread based on
5476          * current settings
5477          */
5478         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5479                 ext4_unregister_li_request(sb);
5480         else {
5481                 ext4_group_t first_not_zeroed;
5482                 first_not_zeroed = ext4_has_uninit_itable(sb);
5483                 ext4_register_li_request(sb, first_not_zeroed);
5484         }
5485
5486         /*
5487          * Handle creation of system zone data early because it can fail.
5488          * Releasing of existing data is done when we are sure remount will
5489          * succeed.
5490          */
5491         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->system_blks) {
5492                 err = ext4_setup_system_zone(sb);
5493                 if (err)
5494                         goto restore_opts;
5495         }
5496
5497         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5498                 err = ext4_commit_super(sb, 1);
5499                 if (err)
5500                         goto restore_opts;
5501         }
5502
5503 #ifdef CONFIG_QUOTA
5504         if (enable_quota) {
5505                 if (sb_any_quota_suspended(sb))
5506                         dquot_resume(sb, -1);
5507                 else if (ext4_has_feature_quota(sb)) {
5508                         err = ext4_enable_quotas(sb);
5509                         if (err)
5510                                 goto restore_opts;
5511                 }
5512         }
5513         /* Release old quota file names */
5514         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5515                 kfree(old_opts.s_qf_names[i]);
5516 #endif
5517         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->system_blks)
5518                 ext4_release_system_zone(sb);
5519
5520         /*
5521          * Some options can be enabled by ext4 and/or by VFS mount flag
5522          * either way we need to make sure it matches in both *flags and
5523          * s_flags. Copy those selected flags from s_flags to *flags
5524          */
5525         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
5526
5527         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5528         kfree(orig_data);
5529         return 0;
5530
5531 restore_opts:
5532         /*
5533          * If there was a failing r/w to ro transition, we may need to
5534          * re-enable quota
5535          */
5536         if ((sb->s_flags & SB_RDONLY) && !(old_sb_flags & SB_RDONLY) &&
5537             sb_any_quota_suspended(sb))
5538                 dquot_resume(sb, -1);
5539         sb->s_flags = old_sb_flags;
5540         sbi->s_mount_opt = old_opts.s_mount_opt;
5541         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5542         sbi->s_resuid = old_opts.s_resuid;
5543         sbi->s_resgid = old_opts.s_resgid;
5544         sbi->s_commit_interval = old_opts.s_commit_interval;
5545         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5546         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5547         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->system_blks)
5548                 ext4_release_system_zone(sb);
5549 #ifdef CONFIG_QUOTA
5550         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5551         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5552                 to_free[i] = get_qf_name(sb, sbi, i);
5553                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5554         }
5555         synchronize_rcu();
5556         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5557                 kfree(to_free[i]);
5558 #endif
5559         kfree(orig_data);
5560         return err;
5561 }
5562
5563 #ifdef CONFIG_QUOTA
5564 static int ext4_statfs_project(struct super_block *sb,
5565                                kprojid_t projid, struct kstatfs *buf)
5566 {
5567         struct kqid qid;
5568         struct dquot *dquot;
5569         u64 limit;
5570         u64 curblock;
5571
5572         qid = make_kqid_projid(projid);
5573         dquot = dqget(sb, qid);
5574         if (IS_ERR(dquot))
5575                 return PTR_ERR(dquot);
5576         spin_lock(&dquot->dq_dqb_lock);
5577
5578         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5579                  dquot->dq_dqb.dqb_bsoftlimit :
5580                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5581         if (limit && buf->f_blocks > limit) {
5582                 curblock = (dquot->dq_dqb.dqb_curspace +
5583                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5584                 buf->f_blocks = limit;
5585                 buf->f_bfree = buf->f_bavail =
5586                         (buf->f_blocks > curblock) ?
5587                          (buf->f_blocks - curblock) : 0;
5588         }
5589
5590         limit = dquot->dq_dqb.dqb_isoftlimit ?
5591                 dquot->dq_dqb.dqb_isoftlimit :
5592                 dquot->dq_dqb.dqb_ihardlimit;
5593         if (limit && buf->f_files > limit) {
5594                 buf->f_files = limit;
5595                 buf->f_ffree =
5596                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5597                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5598         }
5599
5600         spin_unlock(&dquot->dq_dqb_lock);
5601         dqput(dquot);
5602         return 0;
5603 }
5604 #endif
5605
5606 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5607 {
5608         struct super_block *sb = dentry->d_sb;
5609         struct ext4_sb_info *sbi = EXT4_SB(sb);
5610         struct ext4_super_block *es = sbi->s_es;
5611         ext4_fsblk_t overhead = 0, resv_blocks;
5612         u64 fsid;
5613         s64 bfree;
5614         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5615
5616         if (!test_opt(sb, MINIX_DF))
5617                 overhead = sbi->s_overhead;
5618
5619         buf->f_type = EXT4_SUPER_MAGIC;
5620         buf->f_bsize = sb->s_blocksize;
5621         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5622         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5623                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5624         /* prevent underflow in case that few free space is available */
5625         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5626         buf->f_bavail = buf->f_bfree -
5627                         (ext4_r_blocks_count(es) + resv_blocks);
5628         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5629                 buf->f_bavail = 0;
5630         buf->f_files = le32_to_cpu(es->s_inodes_count);
5631         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5632         buf->f_namelen = EXT4_NAME_LEN;
5633         fsid = le64_to_cpup((void *)es->s_uuid) ^
5634                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5635         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5636         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5637
5638 #ifdef CONFIG_QUOTA
5639         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5640             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5641                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5642 #endif
5643         return 0;
5644 }
5645
5646
5647 #ifdef CONFIG_QUOTA
5648
5649 /*
5650  * Helper functions so that transaction is started before we acquire dqio_sem
5651  * to keep correct lock ordering of transaction > dqio_sem
5652  */
5653 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5654 {
5655         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5656 }
5657
5658 static int ext4_write_dquot(struct dquot *dquot)
5659 {
5660         int ret, err;
5661         handle_t *handle;
5662         struct inode *inode;
5663
5664         inode = dquot_to_inode(dquot);
5665         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5666                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5667         if (IS_ERR(handle))
5668                 return PTR_ERR(handle);
5669         ret = dquot_commit(dquot);
5670         err = ext4_journal_stop(handle);
5671         if (!ret)
5672                 ret = err;
5673         return ret;
5674 }
5675
5676 static int ext4_acquire_dquot(struct dquot *dquot)
5677 {
5678         int ret, err;
5679         handle_t *handle;
5680
5681         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5682                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5683         if (IS_ERR(handle))
5684                 return PTR_ERR(handle);
5685         ret = dquot_acquire(dquot);
5686         err = ext4_journal_stop(handle);
5687         if (!ret)
5688                 ret = err;
5689         return ret;
5690 }
5691
5692 static int ext4_release_dquot(struct dquot *dquot)
5693 {
5694         int ret, err;
5695         handle_t *handle;
5696
5697         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5698                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5699         if (IS_ERR(handle)) {
5700                 /* Release dquot anyway to avoid endless cycle in dqput() */
5701                 dquot_release(dquot);
5702                 return PTR_ERR(handle);
5703         }
5704         ret = dquot_release(dquot);
5705         err = ext4_journal_stop(handle);
5706         if (!ret)
5707                 ret = err;
5708         return ret;
5709 }
5710
5711 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5712 {
5713         struct super_block *sb = dquot->dq_sb;
5714         struct ext4_sb_info *sbi = EXT4_SB(sb);
5715
5716         /* Are we journaling quotas? */
5717         if (ext4_has_feature_quota(sb) ||
5718             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5719                 dquot_mark_dquot_dirty(dquot);
5720                 return ext4_write_dquot(dquot);
5721         } else {
5722                 return dquot_mark_dquot_dirty(dquot);
5723         }
5724 }
5725
5726 static int ext4_write_info(struct super_block *sb, int type)
5727 {
5728         int ret, err;
5729         handle_t *handle;
5730
5731         /* Data block + inode block */
5732         handle = ext4_journal_start_sb(sb, EXT4_HT_QUOTA, 2);
5733         if (IS_ERR(handle))
5734                 return PTR_ERR(handle);
5735         ret = dquot_commit_info(sb, type);
5736         err = ext4_journal_stop(handle);
5737         if (!ret)
5738                 ret = err;
5739         return ret;
5740 }
5741
5742 /*
5743  * Turn on quotas during mount time - we need to find
5744  * the quota file and such...
5745  */
5746 static int ext4_quota_on_mount(struct super_block *sb, int type)
5747 {
5748         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5749                                         EXT4_SB(sb)->s_jquota_fmt, type);
5750 }
5751
5752 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5753 {
5754         struct ext4_inode_info *ei = EXT4_I(inode);
5755
5756         /* The first argument of lockdep_set_subclass has to be
5757          * *exactly* the same as the argument to init_rwsem() --- in
5758          * this case, in init_once() --- or lockdep gets unhappy
5759          * because the name of the lock is set using the
5760          * stringification of the argument to init_rwsem().
5761          */
5762         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5763         lockdep_set_subclass(&ei->i_data_sem, subclass);
5764 }
5765
5766 /*
5767  * Standard function to be called on quota_on
5768  */
5769 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5770                          const struct path *path)
5771 {
5772         int err;
5773
5774         if (!test_opt(sb, QUOTA))
5775                 return -EINVAL;
5776
5777         /* Quotafile not on the same filesystem? */
5778         if (path->dentry->d_sb != sb)
5779                 return -EXDEV;
5780
5781         /* Quota already enabled for this file? */
5782         if (IS_NOQUOTA(d_inode(path->dentry)))
5783                 return -EBUSY;
5784
5785         /* Journaling quota? */
5786         if (EXT4_SB(sb)->s_qf_names[type]) {
5787                 /* Quotafile not in fs root? */
5788                 if (path->dentry->d_parent != sb->s_root)
5789                         ext4_msg(sb, KERN_WARNING,
5790                                 "Quota file not on filesystem root. "
5791                                 "Journaled quota will not work");
5792                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5793         } else {
5794                 /*
5795                  * Clear the flag just in case mount options changed since
5796                  * last time.
5797                  */
5798                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5799         }
5800
5801         /*
5802          * When we journal data on quota file, we have to flush journal to see
5803          * all updates to the file when we bypass pagecache...
5804          */
5805         if (EXT4_SB(sb)->s_journal &&
5806             ext4_should_journal_data(d_inode(path->dentry))) {
5807                 /*
5808                  * We don't need to lock updates but journal_flush() could
5809                  * otherwise be livelocked...
5810                  */
5811                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5812                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5813                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5814                 if (err)
5815                         return err;
5816         }
5817
5818         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5819         err = dquot_quota_on(sb, type, format_id, path);
5820         if (!err) {
5821                 struct inode *inode = d_inode(path->dentry);
5822                 handle_t *handle;
5823
5824                 /*
5825                  * Set inode flags to prevent userspace from messing with quota
5826                  * files. If this fails, we return success anyway since quotas
5827                  * are already enabled and this is not a hard failure.
5828                  */
5829                 inode_lock(inode);
5830                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5831                 if (IS_ERR(handle))
5832                         goto unlock_inode;
5833                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5834                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5835                                 S_NOATIME | S_IMMUTABLE);
5836                 ext4_mark_inode_dirty(handle, inode);
5837                 ext4_journal_stop(handle);
5838         unlock_inode:
5839                 inode_unlock(inode);
5840                 if (err)
5841                         dquot_quota_off(sb, type);
5842         }
5843         if (err)
5844                 lockdep_set_quota_inode(path->dentry->d_inode,
5845                                              I_DATA_SEM_NORMAL);
5846         return err;
5847 }
5848
5849 static inline bool ext4_check_quota_inum(int type, unsigned long qf_inum)
5850 {
5851         switch (type) {
5852         case USRQUOTA:
5853                 return qf_inum == EXT4_USR_QUOTA_INO;
5854         case GRPQUOTA:
5855                 return qf_inum == EXT4_GRP_QUOTA_INO;
5856         case PRJQUOTA:
5857                 return qf_inum >= EXT4_GOOD_OLD_FIRST_INO;
5858         default:
5859                 BUG();
5860         }
5861 }
5862
5863 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5864                              unsigned int flags)
5865 {
5866         int err;
5867         struct inode *qf_inode;
5868         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5869                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5870                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5871                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5872         };
5873
5874         BUG_ON(!ext4_has_feature_quota(sb));
5875
5876         if (!qf_inums[type])
5877                 return -EPERM;
5878
5879         if (!ext4_check_quota_inum(type, qf_inums[type])) {
5880                 ext4_error(sb, "Bad quota inum: %lu, type: %d",
5881                                 qf_inums[type], type);
5882                 return -EUCLEAN;
5883         }
5884
5885         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5886         if (IS_ERR(qf_inode)) {
5887                 ext4_error(sb, "Bad quota inode: %lu, type: %d",
5888                                 qf_inums[type], type);
5889                 return PTR_ERR(qf_inode);
5890         }
5891
5892         /* Don't account quota for quota files to avoid recursion */
5893         qf_inode->i_flags |= S_NOQUOTA;
5894         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5895         err = dquot_enable(qf_inode, type, format_id, flags);
5896         if (err)
5897                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5898         iput(qf_inode);
5899
5900         return err;
5901 }
5902
5903 /* Enable usage tracking for all quota types. */
5904 static int ext4_enable_quotas(struct super_block *sb)
5905 {
5906         int type, err = 0;
5907         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5908                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5909                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5910                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5911         };
5912         bool quota_mopt[EXT4_MAXQUOTAS] = {
5913                 test_opt(sb, USRQUOTA),
5914                 test_opt(sb, GRPQUOTA),
5915                 test_opt(sb, PRJQUOTA),
5916         };
5917
5918         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5919         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5920                 if (qf_inums[type]) {
5921                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5922                                 DQUOT_USAGE_ENABLED |
5923                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5924                         if (err) {
5925                                 ext4_warning(sb,
5926                                         "Failed to enable quota tracking "
5927                                         "(type=%d, err=%d, ino=%lu). "
5928                                         "Please run e2fsck to fix.", type,
5929                                         err, qf_inums[type]);
5930                                 for (type--; type >= 0; type--) {
5931                                         struct inode *inode;
5932
5933                                         inode = sb_dqopt(sb)->files[type];
5934                                         if (inode)
5935                                                 inode = igrab(inode);
5936                                         dquot_quota_off(sb, type);
5937                                         if (inode) {
5938                                                 lockdep_set_quota_inode(inode,
5939                                                         I_DATA_SEM_NORMAL);
5940                                                 iput(inode);
5941                                         }
5942                                 }
5943
5944                                 return err;
5945                         }
5946                 }
5947         }
5948         return 0;
5949 }
5950
5951 static int ext4_quota_off(struct super_block *sb, int type)
5952 {
5953         struct inode *inode = sb_dqopt(sb)->files[type];
5954         handle_t *handle;
5955         int err;
5956
5957         /* Force all delayed allocation blocks to be allocated.
5958          * Caller already holds s_umount sem */
5959         if (test_opt(sb, DELALLOC))
5960                 sync_filesystem(sb);
5961
5962         if (!inode || !igrab(inode))
5963                 goto out;
5964
5965         err = dquot_quota_off(sb, type);
5966         if (err || ext4_has_feature_quota(sb))
5967                 goto out_put;
5968
5969         inode_lock(inode);
5970         /*
5971          * Update modification times of quota files when userspace can
5972          * start looking at them. If we fail, we return success anyway since
5973          * this is not a hard failure and quotas are already disabled.
5974          */
5975         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5976         if (IS_ERR(handle))
5977                 goto out_unlock;
5978         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5979         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5980         inode->i_mtime = inode->i_ctime = current_time(inode);
5981         ext4_mark_inode_dirty(handle, inode);
5982         ext4_journal_stop(handle);
5983 out_unlock:
5984         inode_unlock(inode);
5985 out_put:
5986         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5987         iput(inode);
5988         return err;
5989 out:
5990         return dquot_quota_off(sb, type);
5991 }
5992
5993 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5994  * acquiring the locks... As quota files are never truncated and quota code
5995  * itself serializes the operations (and no one else should touch the files)
5996  * we don't have to be afraid of races */
5997 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5998                                size_t len, loff_t off)
5999 {
6000         struct inode *inode = sb_dqopt(sb)->files[type];
6001         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6002         int offset = off & (sb->s_blocksize - 1);
6003         int tocopy;
6004         size_t toread;
6005         struct buffer_head *bh;
6006         loff_t i_size = i_size_read(inode);
6007
6008         if (off > i_size)
6009                 return 0;
6010         if (off+len > i_size)
6011                 len = i_size-off;
6012         toread = len;
6013         while (toread > 0) {
6014                 tocopy = sb->s_blocksize - offset < toread ?
6015                                 sb->s_blocksize - offset : toread;
6016                 bh = ext4_bread(NULL, inode, blk, 0);
6017                 if (IS_ERR(bh))
6018                         return PTR_ERR(bh);
6019                 if (!bh)        /* A hole? */
6020                         memset(data, 0, tocopy);
6021                 else
6022                         memcpy(data, bh->b_data+offset, tocopy);
6023                 brelse(bh);
6024                 offset = 0;
6025                 toread -= tocopy;
6026                 data += tocopy;
6027                 blk++;
6028         }
6029         return len;
6030 }
6031
6032 /* Write to quotafile (we know the transaction is already started and has
6033  * enough credits) */
6034 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6035                                 const char *data, size_t len, loff_t off)
6036 {
6037         struct inode *inode = sb_dqopt(sb)->files[type];
6038         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6039         int err, offset = off & (sb->s_blocksize - 1);
6040         int retries = 0;
6041         struct buffer_head *bh;
6042         handle_t *handle = journal_current_handle();
6043
6044         if (!handle) {
6045                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6046                         " cancelled because transaction is not started",
6047                         (unsigned long long)off, (unsigned long long)len);
6048                 return -EIO;
6049         }
6050         /*
6051          * Since we account only one data block in transaction credits,
6052          * then it is impossible to cross a block boundary.
6053          */
6054         if (sb->s_blocksize - offset < len) {
6055                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6056                         " cancelled because not block aligned",
6057                         (unsigned long long)off, (unsigned long long)len);
6058                 return -EIO;
6059         }
6060
6061         do {
6062                 bh = ext4_bread(handle, inode, blk,
6063                                 EXT4_GET_BLOCKS_CREATE |
6064                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6065         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
6066                  ext4_should_retry_alloc(inode->i_sb, &retries));
6067         if (IS_ERR(bh))
6068                 return PTR_ERR(bh);
6069         if (!bh)
6070                 goto out;
6071         BUFFER_TRACE(bh, "get write access");
6072         err = ext4_journal_get_write_access(handle, bh);
6073         if (err) {
6074                 brelse(bh);
6075                 return err;
6076         }
6077         lock_buffer(bh);
6078         memcpy(bh->b_data+offset, data, len);
6079         flush_dcache_page(bh->b_page);
6080         unlock_buffer(bh);
6081         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6082         brelse(bh);
6083 out:
6084         if (inode->i_size < off + len) {
6085                 i_size_write(inode, off + len);
6086                 EXT4_I(inode)->i_disksize = inode->i_size;
6087                 ext4_mark_inode_dirty(handle, inode);
6088         }
6089         return len;
6090 }
6091
6092 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid)
6093 {
6094         const struct quota_format_ops   *ops;
6095
6096         if (!sb_has_quota_loaded(sb, qid->type))
6097                 return -ESRCH;
6098         ops = sb_dqopt(sb)->ops[qid->type];
6099         if (!ops || !ops->get_next_id)
6100                 return -ENOSYS;
6101         return dquot_get_next_id(sb, qid);
6102 }
6103 #endif
6104
6105 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6106                        const char *dev_name, void *data)
6107 {
6108         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6109 }
6110
6111 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6112 static inline void register_as_ext2(void)
6113 {
6114         int err = register_filesystem(&ext2_fs_type);
6115         if (err)
6116                 printk(KERN_WARNING
6117                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6118 }
6119
6120 static inline void unregister_as_ext2(void)
6121 {
6122         unregister_filesystem(&ext2_fs_type);
6123 }
6124
6125 static inline int ext2_feature_set_ok(struct super_block *sb)
6126 {
6127         if (ext4_has_unknown_ext2_incompat_features(sb))
6128                 return 0;
6129         if (sb_rdonly(sb))
6130                 return 1;
6131         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6132                 return 0;
6133         return 1;
6134 }
6135 #else
6136 static inline void register_as_ext2(void) { }
6137 static inline void unregister_as_ext2(void) { }
6138 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6139 #endif
6140
6141 static inline void register_as_ext3(void)
6142 {
6143         int err = register_filesystem(&ext3_fs_type);
6144         if (err)
6145                 printk(KERN_WARNING
6146                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6147 }
6148
6149 static inline void unregister_as_ext3(void)
6150 {
6151         unregister_filesystem(&ext3_fs_type);
6152 }
6153
6154 static inline int ext3_feature_set_ok(struct super_block *sb)
6155 {
6156         if (ext4_has_unknown_ext3_incompat_features(sb))
6157                 return 0;
6158         if (!ext4_has_feature_journal(sb))
6159                 return 0;
6160         if (sb_rdonly(sb))
6161                 return 1;
6162         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6163                 return 0;
6164         return 1;
6165 }
6166
6167 static struct file_system_type ext4_fs_type = {
6168         .owner          = THIS_MODULE,
6169         .name           = "ext4",
6170         .mount          = ext4_mount,
6171         .kill_sb        = kill_block_super,
6172         .fs_flags       = FS_REQUIRES_DEV,
6173 };
6174 MODULE_ALIAS_FS("ext4");
6175
6176 /* Shared across all ext4 file systems */
6177 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6178
6179 static int __init ext4_init_fs(void)
6180 {
6181         int i, err;
6182
6183         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6184         ext4_li_info = NULL;
6185         mutex_init(&ext4_li_mtx);
6186
6187         /* Build-time check for flags consistency */
6188         ext4_check_flag_values();
6189
6190         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6191                 init_waitqueue_head(&ext4__ioend_wq[i]);
6192
6193         err = ext4_init_es();
6194         if (err)
6195                 return err;
6196
6197         err = ext4_init_pageio();
6198         if (err)
6199                 goto out5;
6200
6201         err = ext4_init_system_zone();
6202         if (err)
6203                 goto out4;
6204
6205         err = ext4_init_sysfs();
6206         if (err)
6207                 goto out3;
6208
6209         err = ext4_init_mballoc();
6210         if (err)
6211                 goto out2;
6212         err = init_inodecache();
6213         if (err)
6214                 goto out1;
6215         register_as_ext3();
6216         register_as_ext2();
6217         err = register_filesystem(&ext4_fs_type);
6218         if (err)
6219                 goto out;
6220
6221         return 0;
6222 out:
6223         unregister_as_ext2();
6224         unregister_as_ext3();
6225         destroy_inodecache();
6226 out1:
6227         ext4_exit_mballoc();
6228 out2:
6229         ext4_exit_sysfs();
6230 out3:
6231         ext4_exit_system_zone();
6232 out4:
6233         ext4_exit_pageio();
6234 out5:
6235         ext4_exit_es();
6236
6237         return err;
6238 }
6239
6240 static void __exit ext4_exit_fs(void)
6241 {
6242         ext4_destroy_lazyinit_thread();
6243         unregister_as_ext2();
6244         unregister_as_ext3();
6245         unregister_filesystem(&ext4_fs_type);
6246         destroy_inodecache();
6247         ext4_exit_mballoc();
6248         ext4_exit_sysfs();
6249         ext4_exit_system_zone();
6250         ext4_exit_pageio();
6251         ext4_exit_es();
6252 }
6253
6254 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6255 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6256 MODULE_LICENSE("GPL");
6257 MODULE_SOFTDEP("pre: crc32c");
6258 module_init(ext4_init_fs)
6259 module_exit(ext4_exit_fs)