fs/ocfs2/move_extents.c

   1 /* -*- mode: c; c-basic-offset: 8; -*-
   2  * vim: noexpandtab sw=8 ts=8 sts=0:
   3  *
   4  * move_extents.c
   5  *
   6  * Copyright (C) 2011 Oracle.  All rights reserved.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public
  10  * License version 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  */
  17 #include <linux/fs.h>
  18 #include <linux/types.h>
  19 #include <linux/mount.h>
  20 #include <linux/swap.h>
  21
  22 #include <cluster/masklog.h>
  23
  24 #include "ocfs2.h"
  25 #include "ocfs2_ioctl.h"
  26
  27 #include "alloc.h"
  28 #include "localalloc.h"
  29 #include "aops.h"
  30 #include "dlmglue.h"
  31 #include "extent_map.h"
  32 #include "inode.h"
  33 #include "journal.h"
  34 #include "suballoc.h"
  35 #include "uptodate.h"
  36 #include "super.h"
  37 #include "dir.h"
  38 #include "buffer_head_io.h"
  39 #include "sysfile.h"
  40 #include "refcounttree.h"
  41 #include "move_extents.h"
  42
  43 struct ocfs2_move_extents_context {
  44         struct inode *inode;
  45         struct file *file;
  46         int auto_defrag;
  47         int partial;
  48         int credits;
  49         u32 new_phys_cpos;
  50         u32 clusters_moved;
  51         u64 refcount_loc;
  52         struct ocfs2_move_extents *range;
  53         struct ocfs2_extent_tree et;
  54         struct ocfs2_alloc_context *meta_ac;
  55         struct ocfs2_alloc_context *data_ac;
  56         struct ocfs2_cached_dealloc_ctxt dealloc;
  57 };
  58
  59 static int __ocfs2_move_extent(handle_t *handle,
  60                                struct ocfs2_move_extents_context *context,
  61                                u32 cpos, u32 len, u32 p_cpos, u32 new_p_cpos,
  62                                int ext_flags)
  63 {
  64         int ret = 0, index;
  65         struct inode *inode = context->inode;
  66         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  67         struct ocfs2_extent_rec *rec, replace_rec;
  68         struct ocfs2_path *path = NULL;
  69         struct ocfs2_extent_list *el;
  70         u64 ino = ocfs2_metadata_cache_owner(context->et.et_ci);
  71         u64 old_blkno = ocfs2_clusters_to_blocks(inode->i_sb, p_cpos);
  72
  73         ret = ocfs2_duplicate_clusters_by_page(handle, inode, cpos,
  74                                                p_cpos, new_p_cpos, len);
  75         if (ret) {
  76                 mlog_errno(ret);
  77                 goto out;
  78         }
  79
  80         memset(&replace_rec, 0, sizeof(replace_rec));
  81         replace_rec.e_cpos = cpu_to_le32(cpos);
  82         replace_rec.e_leaf_clusters = cpu_to_le16(len);
  83         replace_rec.e_blkno = cpu_to_le64(ocfs2_clusters_to_blocks(inode->i_sb,
  84                                                                    new_p_cpos));
  85
  86         path = ocfs2_new_path_from_et(&context->et);
  87         if (!path) {
  88                 ret = -ENOMEM;
  89                 mlog_errno(ret);
  90                 goto out;
  91         }
  92
  93         ret = ocfs2_find_path(INODE_CACHE(inode), path, cpos);
  94         if (ret) {
  95                 mlog_errno(ret);
  96                 goto out;
  97         }
  98
  99         el = path_leaf_el(path);
 100
 101         index = ocfs2_search_extent_list(el, cpos);
 102         if (index == -1) {
 103                 ret = ocfs2_error(inode->i_sb,
 104                                   "Inode %llu has an extent at cpos %u which can no longer be found\n",
 105                                   (unsigned long long)ino, cpos);
 106                 goto out;
 107         }
 108
 109         rec = &el->l_recs[index];
 110
 111         BUG_ON(ext_flags != rec->e_flags);
 112         /*
 113          * after moving/defraging to new location, the extent is not going
 114          * to be refcounted anymore.
 115          */
 116         replace_rec.e_flags = ext_flags & ~OCFS2_EXT_REFCOUNTED;
 117
 118         ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode),
 119                                       context->et.et_root_bh,
 120                                       OCFS2_JOURNAL_ACCESS_WRITE);
 121         if (ret) {
 122                 mlog_errno(ret);
 123                 goto out;
 124         }
 125
 126         ret = ocfs2_split_extent(handle, &context->et, path, index,
 127                                  &replace_rec, context->meta_ac,
 128                                  &context->dealloc);
 129         if (ret) {
 130                 mlog_errno(ret);
 131                 goto out;
 132         }
 133
 134         ocfs2_journal_dirty(handle, context->et.et_root_bh);
 135
 136         context->new_phys_cpos = new_p_cpos;
 137
 138         /*
 139          * need I to append truncate log for old clusters?
 140          */
 141         if (old_blkno) {
 142                 if (ext_flags & OCFS2_EXT_REFCOUNTED)
 143                         ret = ocfs2_decrease_refcount(inode, handle,
 144                                         ocfs2_blocks_to_clusters(osb->sb,
 145                                                                  old_blkno),
 146                                         len, context->meta_ac,
 147                                         &context->dealloc, 1);
 148                 else
 149                         ret = ocfs2_truncate_log_append(osb, handle,
 150                                                         old_blkno, len);
 151         }
 152
 153         ocfs2_update_inode_fsync_trans(handle, inode, 0);
 154 out:
 155         ocfs2_free_path(path);
 156         return ret;
 157 }
 158
 159 /*
 160  * lock allocator, and reserve appropriate number of bits for
 161  * meta blocks.
 162  */
 163 static int ocfs2_lock_meta_allocator_move_extents(struct inode *inode,
 164                                         struct ocfs2_extent_tree *et,
 165                                         u32 clusters_to_move,
 166                                         u32 extents_to_split,
 167                                         struct ocfs2_alloc_context **meta_ac,
 168                                         int extra_blocks,
 169                                         int *credits)
 170 {
 171         int ret, num_free_extents;
 172         unsigned int max_recs_needed = 2 * extents_to_split + clusters_to_move;
 173         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 174
 175         num_free_extents = ocfs2_num_free_extents(osb, et);
 176         if (num_free_extents < 0) {
 177                 ret = num_free_extents;
 178                 mlog_errno(ret);
 179                 goto out;
 180         }
 181
 182         if (!num_free_extents ||
 183             (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
 184                 extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
 185
 186         ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, meta_ac);
 187         if (ret) {
 188                 mlog_errno(ret);
 189                 goto out;
 190         }
 191
 192
 193         *credits += ocfs2_calc_extend_credits(osb->sb, et->et_root_el);
 194
 195         mlog(0, "reserve metadata_blocks: %d, data_clusters: %u, credits: %d\n",
 196              extra_blocks, clusters_to_move, *credits);
 197 out:
 198         if (ret) {
 199                 if (*meta_ac) {
 200                         ocfs2_free_alloc_context(*meta_ac);
 201                         *meta_ac = NULL;
 202                 }
 203         }
 204
 205         return ret;
 206 }
 207
 208 /*
 209  * Using one journal handle to guarantee the data consistency in case
 210  * crash happens anywhere.
 211  *
 212  *  XXX: defrag can end up with finishing partial extent as requested,
 213  * due to not enough contiguous clusters can be found in allocator.
 214  */
 215 static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
 216                                u32 cpos, u32 phys_cpos, u32 *len, int ext_flags)
 217 {
 218         int ret, credits = 0, extra_blocks = 0, partial = context->partial;
 219         handle_t *handle;
 220         struct inode *inode = context->inode;
 221         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 222         struct inode *tl_inode = osb->osb_tl_inode;
 223         struct ocfs2_refcount_tree *ref_tree = NULL;
 224         u32 new_phys_cpos, new_len;
 225         u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
 226         int need_free = 0;
 227
 228         if ((ext_flags & OCFS2_EXT_REFCOUNTED) && *len) {
 229
 230                 BUG_ON(!(OCFS2_I(inode)->ip_dyn_features &
 231                          OCFS2_HAS_REFCOUNT_FL));
 232
 233                 BUG_ON(!context->refcount_loc);
 234
 235                 ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
 236                                                &ref_tree, NULL);
 237                 if (ret) {
 238                         mlog_errno(ret);
 239                         return ret;
 240                 }
 241
 242                 ret = ocfs2_prepare_refcount_change_for_del(inode,
 243                                                         context->refcount_loc,
 244                                                         phys_blkno,
 245                                                         *len,
 246                                                         &credits,
 247                                                         &extra_blocks);
 248                 if (ret) {
 249                         mlog_errno(ret);
 250                         goto out;
 251                 }
 252         }
 253
 254         ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
 255                                                 *len, 1,
 256                                                 &context->meta_ac,
 257                                                 extra_blocks, &credits);
 258         if (ret) {
 259                 mlog_errno(ret);
 260                 goto out;
 261         }
 262
 263         /*
 264          * should be using allocation reservation strategy there?
 265          *
 266          * if (context->data_ac)
 267          *      context->data_ac->ac_resv = &OCFS2_I(inode)->ip_la_data_resv;
 268          */
 269
 270         mutex_lock(&tl_inode->i_mutex);
 271
 272         if (ocfs2_truncate_log_needs_flush(osb)) {
 273                 ret = __ocfs2_flush_truncate_log(osb);
 274                 if (ret < 0) {
 275                         mlog_errno(ret);
 276                         goto out_unlock_mutex;
 277                 }
 278         }
 279
 280         /*
 281          * Make sure ocfs2_reserve_cluster is called after
 282          * __ocfs2_flush_truncate_log, otherwise, dead lock may happen.
 283          *
 284          * If ocfs2_reserve_cluster is called
 285          * before __ocfs2_flush_truncate_log, dead lock on global bitmap
 286          * may happen.
 287          *
 288          */
 289         ret = ocfs2_reserve_clusters(osb, *len, &context->data_ac);
 290         if (ret) {
 291                 mlog_errno(ret);
 292                 goto out_unlock_mutex;
 293         }
 294
 295         handle = ocfs2_start_trans(osb, credits);
 296         if (IS_ERR(handle)) {
 297                 ret = PTR_ERR(handle);
 298                 mlog_errno(ret);
 299                 goto out_unlock_mutex;
 300         }
 301
 302         ret = __ocfs2_claim_clusters(handle, context->data_ac, 1, *len,
 303                                      &new_phys_cpos, &new_len);
 304         if (ret) {
 305                 mlog_errno(ret);
 306                 goto out_commit;
 307         }
 308
 309         /*
 310          * allowing partial extent moving is kind of 'pros and cons', it makes
 311          * whole defragmentation less likely to fail, on the contrary, the bad
 312          * thing is it may make the fs even more fragmented after moving, let
 313          * userspace make a good decision here.
 314          */
 315         if (new_len != *len) {
 316                 mlog(0, "len_claimed: %u, len: %u\n", new_len, *len);
 317                 if (!partial) {
 318                         context->range->me_flags &= ~OCFS2_MOVE_EXT_FL_COMPLETE;
 319                         ret = -ENOSPC;
 320                         need_free = 1;
 321                         goto out_commit;
 322                 }
 323         }
 324
 325         mlog(0, "cpos: %u, phys_cpos: %u, new_phys_cpos: %u\n", cpos,
 326              phys_cpos, new_phys_cpos);
 327
 328         ret = __ocfs2_move_extent(handle, context, cpos, new_len, phys_cpos,
 329                                   new_phys_cpos, ext_flags);
 330         if (ret)
 331                 mlog_errno(ret);
 332
 333         if (partial && (new_len != *len))
 334                 *len = new_len;
 335
 336         /*
 337          * Here we should write the new page out first if we are
 338          * in write-back mode.
 339          */
 340         ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, *len);
 341         if (ret)
 342                 mlog_errno(ret);
 343
 344 out_commit:
 345         if (need_free && context->data_ac) {
 346                 struct ocfs2_alloc_context *data_ac = context->data_ac;
 347
 348                 if (context->data_ac->ac_which == OCFS2_AC_USE_LOCAL)
 349                         ocfs2_free_local_alloc_bits(osb, handle, data_ac,
 350                                         new_phys_cpos, new_len);
 351                 else
 352                         ocfs2_free_clusters(handle,
 353                                         data_ac->ac_inode,
 354                                         data_ac->ac_bh,
 355                                         ocfs2_clusters_to_blocks(osb->sb, new_phys_cpos),
 356                                         new_len);
 357         }
 358
 359         ocfs2_commit_trans(osb, handle);
 360
 361 out_unlock_mutex:
 362         mutex_unlock(&tl_inode->i_mutex);
 363
 364         if (context->data_ac) {
 365                 ocfs2_free_alloc_context(context->data_ac);
 366                 context->data_ac = NULL;
 367         }
 368
 369         if (context->meta_ac) {
 370                 ocfs2_free_alloc_context(context->meta_ac);
 371                 context->meta_ac = NULL;
 372         }
 373
 374 out:
 375         if (ref_tree)
 376                 ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
 377
 378         return ret;
 379 }
 380
 381 /*
 382  * find the victim alloc group, where #blkno fits.
 383  */
 384 static int ocfs2_find_victim_alloc_group(struct inode *inode,
 385                                          u64 vict_blkno,
 386                                          int type, int slot,
 387                                          int *vict_bit,
 388                                          struct buffer_head **ret_bh)
 389 {
 390         int ret, i, bits_per_unit = 0;
 391         u64 blkno;
 392         char namebuf[40];
 393
 394         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 395         struct buffer_head *ac_bh = NULL, *gd_bh = NULL;
 396         struct ocfs2_chain_list *cl;
 397         struct ocfs2_chain_rec *rec;
 398         struct ocfs2_dinode *ac_dinode;
 399         struct ocfs2_group_desc *bg;
 400
 401         ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf), type, slot);
 402         ret = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf,
 403                                          strlen(namebuf), &blkno);
 404         if (ret) {
 405                 ret = -ENOENT;
 406                 goto out;
 407         }
 408
 409         ret = ocfs2_read_blocks_sync(osb, blkno, 1, &ac_bh);
 410         if (ret) {
 411                 mlog_errno(ret);
 412                 goto out;
 413         }
 414
 415         ac_dinode = (struct ocfs2_dinode *)ac_bh->b_data;
 416         cl = &(ac_dinode->id2.i_chain);
 417         rec = &(cl->cl_recs[0]);
 418
 419         if (type == GLOBAL_BITMAP_SYSTEM_INODE)
 420                 bits_per_unit = osb->s_clustersize_bits -
 421                                         inode->i_sb->s_blocksize_bits;
 422         /*
 423          * 'vict_blkno' was out of the valid range.
 424          */
 425         if ((vict_blkno < le64_to_cpu(rec->c_blkno)) ||
 426             (vict_blkno >= ((u64)le32_to_cpu(ac_dinode->id1.bitmap1.i_total) <<
 427                                 bits_per_unit))) {
 428                 ret = -EINVAL;
 429                 goto out;
 430         }
 431
 432         for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
 433
 434                 rec = &(cl->cl_recs[i]);
 435                 if (!rec)
 436                         continue;
 437
 438                 bg = NULL;
 439
 440                 do {
 441                         if (!bg)
 442                                 blkno = le64_to_cpu(rec->c_blkno);
 443                         else
 444                                 blkno = le64_to_cpu(bg->bg_next_group);
 445
 446                         if (gd_bh) {
 447                                 brelse(gd_bh);
 448                                 gd_bh = NULL;
 449                         }
 450
 451                         ret = ocfs2_read_blocks_sync(osb, blkno, 1, &gd_bh);
 452                         if (ret) {
 453                                 mlog_errno(ret);
 454                                 goto out;
 455                         }
 456
 457                         bg = (struct ocfs2_group_desc *)gd_bh->b_data;
 458
 459                         if (vict_blkno < (le64_to_cpu(bg->bg_blkno) +
 460                                                 le16_to_cpu(bg->bg_bits))) {
 461
 462                                 *ret_bh = gd_bh;
 463                                 *vict_bit = (vict_blkno - blkno) >>
 464                                                         bits_per_unit;
 465                                 mlog(0, "find the victim group: #%llu, "
 466                                      "total_bits: %u, vict_bit: %u\n",
 467                                      blkno, le16_to_cpu(bg->bg_bits),
 468                                      *vict_bit);
 469                                 goto out;
 470                         }
 471
 472                 } while (le64_to_cpu(bg->bg_next_group));
 473         }
 474
 475         ret = -EINVAL;
 476 out:
 477         brelse(ac_bh);
 478
 479         /*
 480          * caller has to release the gd_bh properly.
 481          */
 482         return ret;
 483 }
 484
 485 /*
 486  * XXX: helper to validate and adjust moving goal.
 487  */
 488 static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
 489                                                struct ocfs2_move_extents *range)
 490 {
 491         int ret, goal_bit = 0;
 492
 493         struct buffer_head *gd_bh = NULL;
 494         struct ocfs2_group_desc *bg;
 495         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 496         int c_to_b = 1 << (osb->s_clustersize_bits -
 497                                         inode->i_sb->s_blocksize_bits);
 498
 499         /*
 500          * make goal become cluster aligned.
 501          */
 502         range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb,
 503                                                       range->me_goal);
 504         /*
 505          * validate goal sits within global_bitmap, and return the victim
 506          * group desc
 507          */
 508         ret = ocfs2_find_victim_alloc_group(inode, range->me_goal,
 509                                             GLOBAL_BITMAP_SYSTEM_INODE,
 510                                             OCFS2_INVALID_SLOT,
 511                                             &goal_bit, &gd_bh);
 512         if (ret)
 513                 goto out;
 514
 515         bg = (struct ocfs2_group_desc *)gd_bh->b_data;
 516
 517         /*
 518          * moving goal is not allowd to start with a group desc blok(#0 blk)
 519          * let's compromise to the latter cluster.
 520          */
 521         if (range->me_goal == le64_to_cpu(bg->bg_blkno))
 522                 range->me_goal += c_to_b;
 523
 524         /*
 525          * movement is not gonna cross two groups.
 526          */
 527         if ((le16_to_cpu(bg->bg_bits) - goal_bit) * osb->s_clustersize <
 528                                                                 range->me_len) {
 529                 ret = -EINVAL;
 530                 goto out;
 531         }
 532         /*
 533          * more exact validations/adjustments will be performed later during
 534          * moving operation for each extent range.
 535          */
 536         mlog(0, "extents get ready to be moved to #%llu block\n",
 537              range->me_goal);
 538
 539 out:
 540         brelse(gd_bh);
 541
 542         return ret;
 543 }
 544
 545 static void ocfs2_probe_alloc_group(struct inode *inode, struct buffer_head *bh,
 546                                     int *goal_bit, u32 move_len, u32 max_hop,
 547                                     u32 *phys_cpos)
 548 {
 549         int i, used, last_free_bits = 0, base_bit = *goal_bit;
 550         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 551         u32 base_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
 552                                                  le64_to_cpu(gd->bg_blkno));
 553
 554         for (i = base_bit; i < le16_to_cpu(gd->bg_bits); i++) {
 555
 556                 used = ocfs2_test_bit(i, (unsigned long *)gd->bg_bitmap);
 557                 if (used) {
 558                         /*
 559                          * we even tried searching the free chunk by jumping
 560                          * a 'max_hop' distance, but still failed.
 561                          */
 562                         if ((i - base_bit) > max_hop) {
 563                                 *phys_cpos = 0;
 564                                 break;
 565                         }
 566
 567                         if (last_free_bits)
 568                                 last_free_bits = 0;
 569
 570                         continue;
 571                 } else
 572                         last_free_bits++;
 573
 574                 if (last_free_bits == move_len) {
 575                         *goal_bit = i;
 576                         *phys_cpos = base_cpos + i;
 577                         break;
 578                 }
 579         }
 580
 581         mlog(0, "found phys_cpos: %u to fit the wanted moving.\n", *phys_cpos);
 582 }
 583
 584 static int ocfs2_move_extent(struct ocfs2_move_extents_context *context,
 585                              u32 cpos, u32 phys_cpos, u32 *new_phys_cpos,
 586                              u32 len, int ext_flags)
 587 {
 588         int ret, credits = 0, extra_blocks = 0, goal_bit = 0;
 589         handle_t *handle;
 590         struct inode *inode = context->inode;
 591         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 592         struct inode *tl_inode = osb->osb_tl_inode;
 593         struct inode *gb_inode = NULL;
 594         struct buffer_head *gb_bh = NULL;
 595         struct buffer_head *gd_bh = NULL;
 596         struct ocfs2_group_desc *gd;
 597         struct ocfs2_refcount_tree *ref_tree = NULL;
 598         u32 move_max_hop = ocfs2_blocks_to_clusters(inode->i_sb,
 599                                                     context->range->me_threshold);
 600         u64 phys_blkno, new_phys_blkno;
 601
 602         phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
 603
 604         if ((ext_flags & OCFS2_EXT_REFCOUNTED) && len) {
 605
 606                 BUG_ON(!(OCFS2_I(inode)->ip_dyn_features &
 607                          OCFS2_HAS_REFCOUNT_FL));
 608
 609                 BUG_ON(!context->refcount_loc);
 610
 611                 ret = ocfs2_lock_refcount_tree(osb, context->refcount_loc, 1,
 612                                                &ref_tree, NULL);
 613                 if (ret) {
 614                         mlog_errno(ret);
 615                         return ret;
 616                 }
 617
 618                 ret = ocfs2_prepare_refcount_change_for_del(inode,
 619                                                         context->refcount_loc,
 620                                                         phys_blkno,
 621                                                         len,
 622                                                         &credits,
 623                                                         &extra_blocks);
 624                 if (ret) {
 625                         mlog_errno(ret);
 626                         goto out;
 627                 }
 628         }
 629
 630         ret = ocfs2_lock_meta_allocator_move_extents(inode, &context->et,
 631                                                 len, 1,
 632                                                 &context->meta_ac,
 633                                                 extra_blocks, &credits);
 634         if (ret) {
 635                 mlog_errno(ret);
 636                 goto out;
 637         }
 638
 639         /*
 640          * need to count 2 extra credits for global_bitmap inode and
 641          * group descriptor.
 642          */
 643         credits += OCFS2_INODE_UPDATE_CREDITS + 1;
 644
 645         /*
 646          * ocfs2_move_extent() didn't reserve any clusters in lock_allocators()
 647          * logic, while we still need to lock the global_bitmap.
 648          */
 649         gb_inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE,
 650                                                OCFS2_INVALID_SLOT);
 651         if (!gb_inode) {
 652                 mlog(ML_ERROR, "unable to get global_bitmap inode\n");
 653                 ret = -EIO;
 654                 goto out;
 655         }
 656
 657         mutex_lock(&gb_inode->i_mutex);
 658
 659         ret = ocfs2_inode_lock(gb_inode, &gb_bh, 1);
 660         if (ret) {
 661                 mlog_errno(ret);
 662                 goto out_unlock_gb_mutex;
 663         }
 664
 665         mutex_lock(&tl_inode->i_mutex);
 666
 667         handle = ocfs2_start_trans(osb, credits);
 668         if (IS_ERR(handle)) {
 669                 ret = PTR_ERR(handle);
 670                 mlog_errno(ret);
 671                 goto out_unlock_tl_inode;
 672         }
 673
 674         new_phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, *new_phys_cpos);
 675         ret = ocfs2_find_victim_alloc_group(inode, new_phys_blkno,
 676                                             GLOBAL_BITMAP_SYSTEM_INODE,
 677                                             OCFS2_INVALID_SLOT,
 678                                             &goal_bit, &gd_bh);
 679         if (ret) {
 680                 mlog_errno(ret);
 681                 goto out_commit;
 682         }
 683
 684         /*
 685          * probe the victim cluster group to find a proper
 686          * region to fit wanted movement, it even will perfrom
 687          * a best-effort attempt by compromising to a threshold
 688          * around the goal.
 689          */
 690         ocfs2_probe_alloc_group(inode, gd_bh, &goal_bit, len, move_max_hop,
 691                                 new_phys_cpos);
 692         if (!*new_phys_cpos) {
 693                 ret = -ENOSPC;
 694                 goto out_commit;
 695         }
 696
 697         ret = __ocfs2_move_extent(handle, context, cpos, len, phys_cpos,
 698                                   *new_phys_cpos, ext_flags);
 699         if (ret) {
 700                 mlog_errno(ret);
 701                 goto out_commit;
 702         }
 703
 704         gd = (struct ocfs2_group_desc *)gd_bh->b_data;
 705         ret = ocfs2_alloc_dinode_update_counts(gb_inode, handle, gb_bh, len,
 706                                                le16_to_cpu(gd->bg_chain));
 707         if (ret) {
 708                 mlog_errno(ret);
 709                 goto out_commit;
 710         }
 711
 712         ret = ocfs2_block_group_set_bits(handle, gb_inode, gd, gd_bh,
 713                                          goal_bit, len);
 714         if (ret) {
 715                 ocfs2_rollback_alloc_dinode_counts(gb_inode, gb_bh, len,
 716                                                le16_to_cpu(gd->bg_chain));
 717                 mlog_errno(ret);
 718         }
 719
 720         /*
 721          * Here we should write the new page out first if we are
 722          * in write-back mode.
 723          */
 724         ret = ocfs2_cow_sync_writeback(inode->i_sb, context->inode, cpos, len);
 725         if (ret)
 726                 mlog_errno(ret);
 727
 728 out_commit:
 729         ocfs2_commit_trans(osb, handle);
 730         brelse(gd_bh);
 731
 732 out_unlock_tl_inode:
 733         mutex_unlock(&tl_inode->i_mutex);
 734
 735         ocfs2_inode_unlock(gb_inode, 1);
 736 out_unlock_gb_mutex:
 737         mutex_unlock(&gb_inode->i_mutex);
 738         brelse(gb_bh);
 739         iput(gb_inode);
 740
 741 out:
 742         if (context->meta_ac) {
 743                 ocfs2_free_alloc_context(context->meta_ac);
 744                 context->meta_ac = NULL;
 745         }
 746
 747         if (ref_tree)
 748                 ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
 749
 750         return ret;
 751 }
 752
 753 /*
 754  * Helper to calculate the defraging length in one run according to threshold.
 755  */
 756 static void ocfs2_calc_extent_defrag_len(u32 *alloc_size, u32 *len_defraged,
 757                                          u32 threshold, int *skip)
 758 {
 759         if ((*alloc_size + *len_defraged) < threshold) {
 760                 /*
 761                  * proceed defragmentation until we meet the thresh
 762                  */
 763                 *len_defraged += *alloc_size;
 764         } else if (*len_defraged == 0) {
 765                 /*
 766                  * XXX: skip a large extent.
 767                  */
 768                 *skip = 1;
 769         } else {
 770                 /*
 771                  * split this extent to coalesce with former pieces as
 772                  * to reach the threshold.
 773                  *
 774                  * we're done here with one cycle of defragmentation
 775                  * in a size of 'thresh', resetting 'len_defraged'
 776                  * forces a new defragmentation.
 777                  */
 778                 *alloc_size = threshold - *len_defraged;
 779                 *len_defraged = 0;
 780         }
 781 }
 782
 783 static int __ocfs2_move_extents_range(struct buffer_head *di_bh,
 784                                 struct ocfs2_move_extents_context *context)
 785 {
 786         int ret = 0, flags, do_defrag, skip = 0;
 787         u32 cpos, phys_cpos, move_start, len_to_move, alloc_size;
 788         u32 len_defraged = 0, defrag_thresh = 0, new_phys_cpos = 0;
 789
 790         struct inode *inode = context->inode;
 791         struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 792         struct ocfs2_move_extents *range = context->range;
 793         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 794
 795         if ((i_size_read(inode) == 0) || (range->me_len == 0))
 796                 return 0;
 797
 798         if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
 799                 return 0;
 800
 801         context->refcount_loc = le64_to_cpu(di->i_refcount_loc);
 802
 803         ocfs2_init_dinode_extent_tree(&context->et, INODE_CACHE(inode), di_bh);
 804         ocfs2_init_dealloc_ctxt(&context->dealloc);
 805
 806         /*
 807          * TO-DO XXX:
 808          *
 809          * - xattr extents.
 810          */
 811
 812         do_defrag = context->auto_defrag;
 813
 814         /*
 815          * extents moving happens in unit of clusters, for the sake
 816          * of simplicity, we may ignore two clusters where 'byte_start'
 817          * and 'byte_start + len' were within.
 818          */
 819         move_start = ocfs2_clusters_for_bytes(osb->sb, range->me_start);
 820         len_to_move = (range->me_start + range->me_len) >>
 821                                                 osb->s_clustersize_bits;
 822         if (len_to_move >= move_start)
 823                 len_to_move -= move_start;
 824         else
 825                 len_to_move = 0;
 826
 827         if (do_defrag) {
 828                 defrag_thresh = range->me_threshold >> osb->s_clustersize_bits;
 829                 if (defrag_thresh <= 1)
 830                         goto done;
 831         } else
 832                 new_phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb,
 833                                                          range->me_goal);
 834
 835         mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, clen: %u, "
 836              "thresh: %u\n",
 837              (unsigned long long)OCFS2_I(inode)->ip_blkno,
 838              (unsigned long long)range->me_start,
 839              (unsigned long long)range->me_len,
 840              move_start, len_to_move, defrag_thresh);
 841
 842         cpos = move_start;
 843         while (len_to_move) {
 844                 ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &alloc_size,
 845                                          &flags);
 846                 if (ret) {
 847                         mlog_errno(ret);
 848                         goto out;
 849                 }
 850
 851                 if (alloc_size > len_to_move)
 852                         alloc_size = len_to_move;
 853
 854                 /*
 855                  * XXX: how to deal with a hole:
 856                  *
 857                  * - skip the hole of course
 858                  * - force a new defragmentation
 859                  */
 860                 if (!phys_cpos) {
 861                         if (do_defrag)
 862                                 len_defraged = 0;
 863
 864                         goto next;
 865                 }
 866
 867                 if (do_defrag) {
 868                         ocfs2_calc_extent_defrag_len(&alloc_size, &len_defraged,
 869                                                      defrag_thresh, &skip);
 870                         /*
 871                          * skip large extents
 872                          */
 873                         if (skip) {
 874                                 skip = 0;
 875                                 goto next;
 876                         }
 877
 878                         mlog(0, "#Defrag: cpos: %u, phys_cpos: %u, "
 879                              "alloc_size: %u, len_defraged: %u\n",
 880                              cpos, phys_cpos, alloc_size, len_defraged);
 881
 882                         ret = ocfs2_defrag_extent(context, cpos, phys_cpos,
 883                                                   &alloc_size, flags);
 884                 } else {
 885                         ret = ocfs2_move_extent(context, cpos, phys_cpos,
 886                                                 &new_phys_cpos, alloc_size,
 887                                                 flags);
 888
 889                         new_phys_cpos += alloc_size;
 890                 }
 891
 892                 if (ret < 0) {
 893                         mlog_errno(ret);
 894                         goto out;
 895                 }
 896
 897                 context->clusters_moved += alloc_size;
 898 next:
 899                 cpos += alloc_size;
 900                 len_to_move -= alloc_size;
 901         }
 902
 903 done:
 904         range->me_flags |= OCFS2_MOVE_EXT_FL_COMPLETE;
 905
 906 out:
 907         range->me_moved_len = ocfs2_clusters_to_bytes(osb->sb,
 908                                                       context->clusters_moved);
 909         range->me_new_offset = ocfs2_clusters_to_bytes(osb->sb,
 910                                                        context->new_phys_cpos);
 911
 912         ocfs2_schedule_truncate_log_flush(osb, 1);
 913         ocfs2_run_deallocs(osb, &context->dealloc);
 914
 915         return ret;
 916 }
 917
 918 static int ocfs2_move_extents(struct ocfs2_move_extents_context *context)
 919 {
 920         int status;
 921         handle_t *handle;
 922         struct inode *inode = context->inode;
 923         struct ocfs2_dinode *di;
 924         struct buffer_head *di_bh = NULL;
 925         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 926
 927         if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
 928                 return -EROFS;
 929
 930         mutex_lock(&inode->i_mutex);
 931
 932         /*
 933          * This prevents concurrent writes from other nodes
 934          */
 935         status = ocfs2_rw_lock(inode, 1);
 936         if (status) {
 937                 mlog_errno(status);
 938                 goto out;
 939         }
 940
 941         status = ocfs2_inode_lock(inode, &di_bh, 1);
 942         if (status) {
 943                 mlog_errno(status);
 944                 goto out_rw_unlock;
 945         }
 946
 947         /*
 948          * rememer ip_xattr_sem also needs to be held if necessary
 949          */
 950         down_write(&OCFS2_I(inode)->ip_alloc_sem);
 951
 952         status = __ocfs2_move_extents_range(di_bh, context);
 953
 954         up_write(&OCFS2_I(inode)->ip_alloc_sem);
 955         if (status) {
 956                 mlog_errno(status);
 957                 goto out_inode_unlock;
 958         }
 959
 960         /*
 961          * We update ctime for these changes
 962          */
 963         handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
 964         if (IS_ERR(handle)) {
 965                 status = PTR_ERR(handle);
 966                 mlog_errno(status);
 967                 goto out_inode_unlock;
 968         }
 969
 970         status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
 971                                          OCFS2_JOURNAL_ACCESS_WRITE);
 972         if (status) {
 973                 mlog_errno(status);
 974                 goto out_commit;
 975         }
 976
 977         di = (struct ocfs2_dinode *)di_bh->b_data;
 978         inode->i_ctime = CURRENT_TIME;
 979         di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
 980         di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 981         ocfs2_update_inode_fsync_trans(handle, inode, 0);
 982
 983         ocfs2_journal_dirty(handle, di_bh);
 984
 985 out_commit:
 986         ocfs2_commit_trans(osb, handle);
 987
 988 out_inode_unlock:
 989         brelse(di_bh);
 990         ocfs2_inode_unlock(inode, 1);
 991 out_rw_unlock:
 992         ocfs2_rw_unlock(inode, 1);
 993 out:
 994         mutex_unlock(&inode->i_mutex);
 995
 996         return status;
 997 }
 998
 999 int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp)
1000 {
1001         int status;
1002
1003         struct inode *inode = file_inode(filp);
1004         struct ocfs2_move_extents range;
1005         struct ocfs2_move_extents_context *context;
1006
1007         if (!argp)
1008                 return -EINVAL;
1009
1010         status = mnt_want_write_file(filp);
1011         if (status)
1012                 return status;
1013
1014         if ((!S_ISREG(inode->i_mode)) || !(filp->f_mode & FMODE_WRITE)) {
1015                 status = -EPERM;
1016                 goto out_drop;
1017         }
1018
1019         if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
1020                 status = -EPERM;
1021                 goto out_drop;
1022         }
1023
1024         context = kzalloc(sizeof(struct ocfs2_move_extents_context), GFP_NOFS);
1025         if (!context) {
1026                 status = -ENOMEM;
1027                 mlog_errno(status);
1028                 goto out_drop;
1029         }
1030
1031         context->inode = inode;
1032         context->file = filp;
1033
1034         if (copy_from_user(&range, argp, sizeof(range))) {
1035                 status = -EFAULT;
1036                 goto out_free;
1037         }
1038
1039         if (range.me_start > i_size_read(inode)) {
1040                 status = -EINVAL;
1041                 goto out_free;
1042         }
1043
1044         if (range.me_start + range.me_len > i_size_read(inode))
1045                         range.me_len = i_size_read(inode) - range.me_start;
1046
1047         context->range = &range;
1048
1049         if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG) {
1050                 context->auto_defrag = 1;
1051                 /*
1052                  * ok, the default theshold for the defragmentation
1053                  * is 1M, since our maximum clustersize was 1M also.
1054                  * any thought?
1055                  */
1056                 if (!range.me_threshold)
1057                         range.me_threshold = 1024 * 1024;
1058
1059                 if (range.me_threshold > i_size_read(inode))
1060                         range.me_threshold = i_size_read(inode);
1061
1062                 if (range.me_flags & OCFS2_MOVE_EXT_FL_PART_DEFRAG)
1063                         context->partial = 1;
1064         } else {
1065                 /*
1066                  * first best-effort attempt to validate and adjust the goal
1067                  * (physical address in block), while it can't guarantee later
1068                  * operation can succeed all the time since global_bitmap may
1069                  * change a bit over time.
1070                  */
1071
1072                 status = ocfs2_validate_and_adjust_move_goal(inode, &range);
1073                 if (status)
1074                         goto out_copy;
1075         }
1076
1077         status = ocfs2_move_extents(context);
1078         if (status)
1079                 mlog_errno(status);
1080 out_copy:
1081         /*
1082          * movement/defragmentation may end up being partially completed,
1083          * that's the reason why we need to return userspace the finished
1084          * length and new_offset even if failure happens somewhere.
1085          */
1086         if (copy_to_user(argp, &range, sizeof(range)))
1087                 status = -EFAULT;
1088
1089 out_free:
1090         kfree(context);
1091 out_drop:
1092         mnt_drop_write_file(filp);
1093
1094         return status;
1095 }