GNU Linux-libre 4.19.264-gnu1
[releases.git] / fs / exofs / super.c
1 /*
2  * Copyright (C) 2005, 2006
3  * Avishay Traeger (avishay@gmail.com)
4  * Copyright (C) 2008, 2009
5  * Boaz Harrosh <ooo@electrozaur.com>
6  *
7  * Copyrights for code taken from ext2:
8  *     Copyright (C) 1992, 1993, 1994, 1995
9  *     Remy Card (card@masi.ibp.fr)
10  *     Laboratoire MASI - Institut Blaise Pascal
11  *     Universite Pierre et Marie Curie (Paris VI)
12  *     from
13  *     linux/fs/minix/inode.c
14  *     Copyright (C) 1991, 1992  Linus Torvalds
15  *
16  * This file is part of exofs.
17  *
18  * exofs is free software; you can redistribute it and/or modify
19  * it under the terms of the GNU General Public License as published by
20  * the Free Software Foundation.  Since it is based on ext2, and the only
21  * valid version of GPL for the Linux kernel is version 2, the only valid
22  * version of GPL for exofs is version 2.
23  *
24  * exofs is distributed in the hope that it will be useful,
25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
27  * GNU General Public License for more details.
28  *
29  * You should have received a copy of the GNU General Public License
30  * along with exofs; if not, write to the Free Software
31  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
32  */
33
34 #include <linux/string.h>
35 #include <linux/parser.h>
36 #include <linux/vfs.h>
37 #include <linux/random.h>
38 #include <linux/module.h>
39 #include <linux/exportfs.h>
40 #include <linux/slab.h>
41 #include <linux/iversion.h>
42
43 #include "exofs.h"
44
45 #define EXOFS_DBGMSG2(M...) do {} while (0)
46
47 /******************************************************************************
48  * MOUNT OPTIONS
49  *****************************************************************************/
50
51 /*
52  * struct to hold what we get from mount options
53  */
54 struct exofs_mountopt {
55         bool is_osdname;
56         const char *dev_name;
57         uint64_t pid;
58         int timeout;
59 };
60
61 /*
62  * exofs-specific mount-time options.
63  */
64 enum { Opt_name, Opt_pid, Opt_to, Opt_err };
65
66 /*
67  * Our mount-time options.  These should ideally be 64-bit unsigned, but the
68  * kernel's parsing functions do not currently support that.  32-bit should be
69  * sufficient for most applications now.
70  */
71 static match_table_t tokens = {
72         {Opt_name, "osdname=%s"},
73         {Opt_pid, "pid=%u"},
74         {Opt_to, "to=%u"},
75         {Opt_err, NULL}
76 };
77
78 /*
79  * The main option parsing method.  Also makes sure that all of the mandatory
80  * mount options were set.
81  */
82 static int parse_options(char *options, struct exofs_mountopt *opts)
83 {
84         char *p;
85         substring_t args[MAX_OPT_ARGS];
86         int option;
87         bool s_pid = false;
88
89         EXOFS_DBGMSG("parse_options %s\n", options);
90         /* defaults */
91         memset(opts, 0, sizeof(*opts));
92         opts->timeout = BLK_DEFAULT_SG_TIMEOUT;
93
94         while ((p = strsep(&options, ",")) != NULL) {
95                 int token;
96                 char str[32];
97
98                 if (!*p)
99                         continue;
100
101                 token = match_token(p, tokens, args);
102                 switch (token) {
103                 case Opt_name:
104                         kfree(opts->dev_name);
105                         opts->dev_name = match_strdup(&args[0]);
106                         if (unlikely(!opts->dev_name)) {
107                                 EXOFS_ERR("Error allocating dev_name");
108                                 return -ENOMEM;
109                         }
110                         opts->is_osdname = true;
111                         break;
112                 case Opt_pid:
113                         if (0 == match_strlcpy(str, &args[0], sizeof(str)))
114                                 return -EINVAL;
115                         opts->pid = simple_strtoull(str, NULL, 0);
116                         if (opts->pid < EXOFS_MIN_PID) {
117                                 EXOFS_ERR("Partition ID must be >= %u",
118                                           EXOFS_MIN_PID);
119                                 return -EINVAL;
120                         }
121                         s_pid = 1;
122                         break;
123                 case Opt_to:
124                         if (match_int(&args[0], &option))
125                                 return -EINVAL;
126                         if (option <= 0) {
127                                 EXOFS_ERR("Timeout must be > 0");
128                                 return -EINVAL;
129                         }
130                         opts->timeout = option * HZ;
131                         break;
132                 }
133         }
134
135         if (!s_pid) {
136                 EXOFS_ERR("Need to specify the following options:\n");
137                 EXOFS_ERR("    -o pid=pid_no_to_use\n");
138                 return -EINVAL;
139         }
140
141         return 0;
142 }
143
144 /******************************************************************************
145  * INODE CACHE
146  *****************************************************************************/
147
148 /*
149  * Our inode cache.  Isn't it pretty?
150  */
151 static struct kmem_cache *exofs_inode_cachep;
152
153 /*
154  * Allocate an inode in the cache
155  */
156 static struct inode *exofs_alloc_inode(struct super_block *sb)
157 {
158         struct exofs_i_info *oi;
159
160         oi = kmem_cache_alloc(exofs_inode_cachep, GFP_KERNEL);
161         if (!oi)
162                 return NULL;
163
164         inode_set_iversion(&oi->vfs_inode, 1);
165         return &oi->vfs_inode;
166 }
167
168 static void exofs_i_callback(struct rcu_head *head)
169 {
170         struct inode *inode = container_of(head, struct inode, i_rcu);
171         kmem_cache_free(exofs_inode_cachep, exofs_i(inode));
172 }
173
174 /*
175  * Remove an inode from the cache
176  */
177 static void exofs_destroy_inode(struct inode *inode)
178 {
179         call_rcu(&inode->i_rcu, exofs_i_callback);
180 }
181
182 /*
183  * Initialize the inode
184  */
185 static void exofs_init_once(void *foo)
186 {
187         struct exofs_i_info *oi = foo;
188
189         inode_init_once(&oi->vfs_inode);
190 }
191
192 /*
193  * Create and initialize the inode cache
194  */
195 static int init_inodecache(void)
196 {
197         exofs_inode_cachep = kmem_cache_create_usercopy("exofs_inode_cache",
198                                 sizeof(struct exofs_i_info), 0,
199                                 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD |
200                                 SLAB_ACCOUNT,
201                                 offsetof(struct exofs_i_info, i_data),
202                                 sizeof_field(struct exofs_i_info, i_data),
203                                 exofs_init_once);
204         if (exofs_inode_cachep == NULL)
205                 return -ENOMEM;
206         return 0;
207 }
208
209 /*
210  * Destroy the inode cache
211  */
212 static void destroy_inodecache(void)
213 {
214         /*
215          * Make sure all delayed rcu free inodes are flushed before we
216          * destroy cache.
217          */
218         rcu_barrier();
219         kmem_cache_destroy(exofs_inode_cachep);
220 }
221
222 /******************************************************************************
223  * Some osd helpers
224  *****************************************************************************/
225 void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
226 {
227         osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
228 }
229
230 static int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
231                     u64 offset, void *p, unsigned length)
232 {
233         struct osd_request *or = osd_start_request(od);
234 /*      struct osd_sense_info osi = {.key = 0};*/
235         int ret;
236
237         if (unlikely(!or)) {
238                 EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
239                 return -ENOMEM;
240         }
241         ret = osd_req_read_kern(or, obj, offset, p, length);
242         if (unlikely(ret)) {
243                 EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
244                 goto out;
245         }
246
247         ret = osd_finalize_request(or, 0, cred, NULL);
248         if (unlikely(ret)) {
249                 EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n", ret);
250                 goto out;
251         }
252
253         ret = osd_execute_request(or);
254         if (unlikely(ret))
255                 EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
256         /* osd_req_decode_sense(or, ret); */
257
258 out:
259         osd_end_request(or);
260         EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
261                       "length=0x%llx dev=%p ret=>%d\n",
262                       _LLU(obj->id), _LLU(offset), _LLU(length), od, ret);
263         return ret;
264 }
265
266 static const struct osd_attr g_attr_sb_stats = ATTR_DEF(
267         EXOFS_APAGE_SB_DATA,
268         EXOFS_ATTR_SB_STATS,
269         sizeof(struct exofs_sb_stats));
270
271 static int __sbi_read_stats(struct exofs_sb_info *sbi)
272 {
273         struct osd_attr attrs[] = {
274                 [0] = g_attr_sb_stats,
275         };
276         struct ore_io_state *ios;
277         int ret;
278
279         ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
280         if (unlikely(ret)) {
281                 EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
282                 return ret;
283         }
284
285         ios->in_attr = attrs;
286         ios->in_attr_len = ARRAY_SIZE(attrs);
287
288         ret = ore_read(ios);
289         if (unlikely(ret)) {
290                 EXOFS_ERR("Error reading super_block stats => %d\n", ret);
291                 goto out;
292         }
293
294         ret = extract_attr_from_ios(ios, &attrs[0]);
295         if (ret) {
296                 EXOFS_ERR("%s: extract_attr of sb_stats failed\n", __func__);
297                 goto out;
298         }
299         if (attrs[0].len) {
300                 struct exofs_sb_stats *ess;
301
302                 if (unlikely(attrs[0].len != sizeof(*ess))) {
303                         EXOFS_ERR("%s: Wrong version of exofs_sb_stats "
304                                   "size(%d) != expected(%zd)\n",
305                                   __func__, attrs[0].len, sizeof(*ess));
306                         goto out;
307                 }
308
309                 ess = attrs[0].val_ptr;
310                 sbi->s_nextid = le64_to_cpu(ess->s_nextid);
311                 sbi->s_numfiles = le32_to_cpu(ess->s_numfiles);
312         }
313
314 out:
315         ore_put_io_state(ios);
316         return ret;
317 }
318
319 static void stats_done(struct ore_io_state *ios, void *p)
320 {
321         ore_put_io_state(ios);
322         /* Good thanks nothing to do anymore */
323 }
324
325 /* Asynchronously write the stats attribute */
326 int exofs_sbi_write_stats(struct exofs_sb_info *sbi)
327 {
328         struct osd_attr attrs[] = {
329                 [0] = g_attr_sb_stats,
330         };
331         struct ore_io_state *ios;
332         int ret;
333
334         ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
335         if (unlikely(ret)) {
336                 EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
337                 return ret;
338         }
339
340         sbi->s_ess.s_nextid   = cpu_to_le64(sbi->s_nextid);
341         sbi->s_ess.s_numfiles = cpu_to_le64(sbi->s_numfiles);
342         attrs[0].val_ptr = &sbi->s_ess;
343
344
345         ios->done = stats_done;
346         ios->private = sbi;
347         ios->out_attr = attrs;
348         ios->out_attr_len = ARRAY_SIZE(attrs);
349
350         ret = ore_write(ios);
351         if (unlikely(ret)) {
352                 EXOFS_ERR("%s: ore_write failed.\n", __func__);
353                 ore_put_io_state(ios);
354         }
355
356         return ret;
357 }
358
359 /******************************************************************************
360  * SUPERBLOCK FUNCTIONS
361  *****************************************************************************/
362 static const struct super_operations exofs_sops;
363 static const struct export_operations exofs_export_ops;
364
365 /*
366  * Write the superblock to the OSD
367  */
368 static int exofs_sync_fs(struct super_block *sb, int wait)
369 {
370         struct exofs_sb_info *sbi;
371         struct exofs_fscb *fscb;
372         struct ore_comp one_comp;
373         struct ore_components oc;
374         struct ore_io_state *ios;
375         int ret = -ENOMEM;
376
377         fscb = kmalloc(sizeof(*fscb), GFP_KERNEL);
378         if (unlikely(!fscb))
379                 return -ENOMEM;
380
381         sbi = sb->s_fs_info;
382
383         /* NOTE: We no longer dirty the super_block anywhere in exofs. The
384          * reason we write the fscb here on unmount is so we can stay backwards
385          * compatible with fscb->s_version == 1. (What we are not compatible
386          * with is if a new version FS crashed and then we try to mount an old
387          * version). Otherwise the exofs_fscb is read-only from mkfs time. All
388          * the writeable info is set in exofs_sbi_write_stats() above.
389          */
390
391         exofs_init_comps(&oc, &one_comp, sbi, EXOFS_SUPER_ID);
392
393         ret = ore_get_io_state(&sbi->layout, &oc, &ios);
394         if (unlikely(ret))
395                 goto out;
396
397         ios->length = offsetof(struct exofs_fscb, s_dev_table_oid);
398         memset(fscb, 0, ios->length);
399         fscb->s_nextid = cpu_to_le64(sbi->s_nextid);
400         fscb->s_numfiles = cpu_to_le64(sbi->s_numfiles);
401         fscb->s_magic = cpu_to_le16(sb->s_magic);
402         fscb->s_newfs = 0;
403         fscb->s_version = EXOFS_FSCB_VER;
404
405         ios->offset = 0;
406         ios->kern_buff = fscb;
407
408         ret = ore_write(ios);
409         if (unlikely(ret))
410                 EXOFS_ERR("%s: ore_write failed.\n", __func__);
411
412 out:
413         EXOFS_DBGMSG("s_nextid=0x%llx ret=%d\n", _LLU(sbi->s_nextid), ret);
414         ore_put_io_state(ios);
415         kfree(fscb);
416         return ret;
417 }
418
419 static void _exofs_print_device(const char *msg, const char *dev_path,
420                                 struct osd_dev *od, u64 pid)
421 {
422         const struct osd_dev_info *odi = osduld_device_info(od);
423
424         printk(KERN_NOTICE "exofs: %s %s osd_name-%s pid-0x%llx\n",
425                 msg, dev_path ?: "", odi->osdname, _LLU(pid));
426 }
427
428 static void exofs_free_sbi(struct exofs_sb_info *sbi)
429 {
430         unsigned numdevs = sbi->oc.numdevs;
431
432         while (numdevs) {
433                 unsigned i = --numdevs;
434                 struct osd_dev *od = ore_comp_dev(&sbi->oc, i);
435
436                 if (od) {
437                         ore_comp_set_dev(&sbi->oc, i, NULL);
438                         osduld_put_device(od);
439                 }
440         }
441         kfree(sbi->oc.ods);
442         kfree(sbi);
443 }
444
445 /*
446  * This function is called when the vfs is freeing the superblock.  We just
447  * need to free our own part.
448  */
449 static void exofs_put_super(struct super_block *sb)
450 {
451         int num_pend;
452         struct exofs_sb_info *sbi = sb->s_fs_info;
453
454         /* make sure there are no pending commands */
455         for (num_pend = atomic_read(&sbi->s_curr_pending); num_pend > 0;
456              num_pend = atomic_read(&sbi->s_curr_pending)) {
457                 wait_queue_head_t wq;
458
459                 printk(KERN_NOTICE "%s: !!Pending operations in flight. "
460                        "This is a BUG. please report to osd-dev@open-osd.org\n",
461                        __func__);
462                 init_waitqueue_head(&wq);
463                 wait_event_timeout(wq,
464                                   (atomic_read(&sbi->s_curr_pending) == 0),
465                                   msecs_to_jiffies(100));
466         }
467
468         _exofs_print_device("Unmounting", NULL, ore_comp_dev(&sbi->oc, 0),
469                             sbi->one_comp.obj.partition);
470
471         exofs_sysfs_sb_del(sbi);
472         exofs_free_sbi(sbi);
473         sb->s_fs_info = NULL;
474 }
475
476 static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
477                                     struct exofs_device_table *dt)
478 {
479         int ret;
480
481         sbi->layout.stripe_unit =
482                                 le64_to_cpu(dt->dt_data_map.cb_stripe_unit);
483         sbi->layout.group_width =
484                                 le32_to_cpu(dt->dt_data_map.cb_group_width);
485         sbi->layout.group_depth =
486                                 le32_to_cpu(dt->dt_data_map.cb_group_depth);
487         sbi->layout.mirrors_p1  =
488                                 le32_to_cpu(dt->dt_data_map.cb_mirror_cnt) + 1;
489         sbi->layout.raid_algorithm  =
490                                 le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
491
492         ret = ore_verify_layout(numdevs, &sbi->layout);
493
494         EXOFS_DBGMSG("exofs: layout: "
495                 "num_comps=%u stripe_unit=0x%x group_width=%u "
496                 "group_depth=0x%llx mirrors_p1=%u raid_algorithm=%u\n",
497                 numdevs,
498                 sbi->layout.stripe_unit,
499                 sbi->layout.group_width,
500                 _LLU(sbi->layout.group_depth),
501                 sbi->layout.mirrors_p1,
502                 sbi->layout.raid_algorithm);
503         return ret;
504 }
505
506 static unsigned __ra_pages(struct ore_layout *layout)
507 {
508         const unsigned _MIN_RA = 32; /* min 128K read-ahead */
509         unsigned ra_pages = layout->group_width * layout->stripe_unit /
510                                 PAGE_SIZE;
511         unsigned max_io_pages = exofs_max_io_pages(layout, ~0);
512
513         ra_pages *= 2; /* two stripes */
514         if (ra_pages < _MIN_RA)
515                 ra_pages = roundup(_MIN_RA, ra_pages / 2);
516
517         if (ra_pages > max_io_pages)
518                 ra_pages = max_io_pages;
519
520         return ra_pages;
521 }
522
523 /* @odi is valid only as long as @fscb_dev is valid */
524 static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev,
525                              struct osd_dev_info *odi)
526 {
527         odi->systemid_len = le32_to_cpu(dt_dev->systemid_len);
528         if (likely(odi->systemid_len))
529                 memcpy(odi->systemid, dt_dev->systemid, OSD_SYSTEMID_LEN);
530
531         odi->osdname_len = le32_to_cpu(dt_dev->osdname_len);
532         odi->osdname = dt_dev->osdname;
533
534         /* FIXME support long names. Will need a _put function */
535         if (dt_dev->long_name_offset)
536                 return -EINVAL;
537
538         /* Make sure osdname is printable!
539          * mkexofs should give us space for a null-terminator else the
540          * device-table is invalid.
541          */
542         if (unlikely(odi->osdname_len >= sizeof(dt_dev->osdname)))
543                 odi->osdname_len = sizeof(dt_dev->osdname) - 1;
544         dt_dev->osdname[odi->osdname_len] = 0;
545
546         /* If it's all zeros something is bad we read past end-of-obj */
547         return !(odi->systemid_len || odi->osdname_len);
548 }
549
550 static int __alloc_dev_table(struct exofs_sb_info *sbi, unsigned numdevs,
551                       struct exofs_dev **peds)
552 {
553         /* Twice bigger table: See exofs_init_comps() and comment at
554          * exofs_read_lookup_dev_table()
555          */
556         const size_t numores = numdevs * 2 - 1;
557         struct exofs_dev *eds;
558         unsigned i;
559
560         sbi->oc.ods = kzalloc(numores * sizeof(struct ore_dev *) +
561                               numdevs * sizeof(struct exofs_dev), GFP_KERNEL);
562         if (unlikely(!sbi->oc.ods)) {
563                 EXOFS_ERR("ERROR: failed allocating Device array[%d]\n",
564                           numdevs);
565                 return -ENOMEM;
566         }
567
568         /* Start of allocated struct exofs_dev entries */
569         *peds = eds = (void *)sbi->oc.ods[numores];
570         /* Initialize pointers into struct exofs_dev */
571         for (i = 0; i < numdevs; ++i)
572                 sbi->oc.ods[i] = &eds[i].ored;
573         return 0;
574 }
575
576 static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi,
577                                        struct osd_dev *fscb_od,
578                                        unsigned table_count)
579 {
580         struct ore_comp comp;
581         struct exofs_device_table *dt;
582         struct exofs_dev *eds;
583         unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) +
584                                              sizeof(*dt);
585         unsigned numdevs, i;
586         int ret;
587
588         dt = kmalloc(table_bytes, GFP_KERNEL);
589         if (unlikely(!dt)) {
590                 EXOFS_ERR("ERROR: allocating %x bytes for device table\n",
591                           table_bytes);
592                 return -ENOMEM;
593         }
594
595         sbi->oc.numdevs = 0;
596
597         comp.obj.partition = sbi->one_comp.obj.partition;
598         comp.obj.id = EXOFS_DEVTABLE_ID;
599         exofs_make_credential(comp.cred, &comp.obj);
600
601         ret = exofs_read_kern(fscb_od, comp.cred, &comp.obj, 0, dt,
602                               table_bytes);
603         if (unlikely(ret)) {
604                 EXOFS_ERR("ERROR: reading device table\n");
605                 goto out;
606         }
607
608         numdevs = le64_to_cpu(dt->dt_num_devices);
609         if (unlikely(!numdevs)) {
610                 ret = -EINVAL;
611                 goto out;
612         }
613         WARN_ON(table_count != numdevs);
614
615         ret = _read_and_match_data_map(sbi, numdevs, dt);
616         if (unlikely(ret))
617                 goto out;
618
619         ret = __alloc_dev_table(sbi, numdevs, &eds);
620         if (unlikely(ret))
621                 goto out;
622         /* exofs round-robins the device table view according to inode
623          * number. We hold a: twice bigger table hence inodes can point
624          * to any device and have a sequential view of the table
625          * starting at this device. See exofs_init_comps()
626          */
627         memcpy(&sbi->oc.ods[numdevs], &sbi->oc.ods[0],
628                 (numdevs - 1) * sizeof(sbi->oc.ods[0]));
629
630         /* create sysfs subdir under which we put the device table
631          * And cluster layout. A Superblock is identified by the string:
632          *      "dev[0].osdname"_"pid"
633          */
634         exofs_sysfs_sb_add(sbi, &dt->dt_dev_table[0]);
635
636         for (i = 0; i < numdevs; i++) {
637                 struct exofs_fscb fscb;
638                 struct osd_dev_info odi;
639                 struct osd_dev *od;
640
641                 if (exofs_devs_2_odi(&dt->dt_dev_table[i], &odi)) {
642                         EXOFS_ERR("ERROR: Read all-zeros device entry\n");
643                         ret = -EINVAL;
644                         goto out;
645                 }
646
647                 printk(KERN_NOTICE "Add device[%d]: osd_name-%s\n",
648                        i, odi.osdname);
649
650                 /* the exofs id is currently the table index */
651                 eds[i].did = i;
652
653                 /* On all devices the device table is identical. The user can
654                  * specify any one of the participating devices on the command
655                  * line. We always keep them in device-table order.
656                  */
657                 if (fscb_od && osduld_device_same(fscb_od, &odi)) {
658                         eds[i].ored.od = fscb_od;
659                         ++sbi->oc.numdevs;
660                         fscb_od = NULL;
661                         exofs_sysfs_odev_add(&eds[i], sbi);
662                         continue;
663                 }
664
665                 od = osduld_info_lookup(&odi);
666                 if (IS_ERR(od)) {
667                         ret = PTR_ERR(od);
668                         EXOFS_ERR("ERROR: device requested is not found "
669                                   "osd_name-%s =>%d\n", odi.osdname, ret);
670                         goto out;
671                 }
672
673                 eds[i].ored.od = od;
674                 ++sbi->oc.numdevs;
675
676                 /* Read the fscb of the other devices to make sure the FS
677                  * partition is there.
678                  */
679                 ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb,
680                                       sizeof(fscb));
681                 if (unlikely(ret)) {
682                         EXOFS_ERR("ERROR: Malformed participating device "
683                                   "error reading fscb osd_name-%s\n",
684                                   odi.osdname);
685                         goto out;
686                 }
687                 exofs_sysfs_odev_add(&eds[i], sbi);
688
689                 /* TODO: verify other information is correct and FS-uuid
690                  *       matches. Benny what did you say about device table
691                  *       generation and old devices?
692                  */
693         }
694
695 out:
696         kfree(dt);
697         if (unlikely(fscb_od && !ret)) {
698                         EXOFS_ERR("ERROR: Bad device-table container device not present\n");
699                         osduld_put_device(fscb_od);
700                         return -EINVAL;
701         }
702         return ret;
703 }
704
705 /*
706  * Read the superblock from the OSD and fill in the fields
707  */
708 static int exofs_fill_super(struct super_block *sb,
709                                 struct exofs_mountopt *opts,
710                                 struct exofs_sb_info *sbi,
711                                 int silent)
712 {
713         struct inode *root;
714         struct osd_dev *od;             /* Master device                 */
715         struct exofs_fscb fscb;         /*on-disk superblock info        */
716         struct ore_comp comp;
717         unsigned table_count;
718         int ret;
719
720         /* use mount options to fill superblock */
721         if (opts->is_osdname) {
722                 struct osd_dev_info odi = {.systemid_len = 0};
723
724                 odi.osdname_len = strlen(opts->dev_name);
725                 odi.osdname = (u8 *)opts->dev_name;
726                 od = osduld_info_lookup(&odi);
727                 kfree(opts->dev_name);
728                 opts->dev_name = NULL;
729         } else {
730                 od = osduld_path_lookup(opts->dev_name);
731         }
732         if (IS_ERR(od)) {
733                 ret = -EINVAL;
734                 goto free_sbi;
735         }
736
737         /* Default layout in case we do not have a device-table */
738         sbi->layout.stripe_unit = PAGE_SIZE;
739         sbi->layout.mirrors_p1 = 1;
740         sbi->layout.group_width = 1;
741         sbi->layout.group_depth = -1;
742         sbi->layout.group_count = 1;
743         sbi->s_timeout = opts->timeout;
744
745         sbi->one_comp.obj.partition = opts->pid;
746         sbi->one_comp.obj.id = 0;
747         exofs_make_credential(sbi->one_comp.cred, &sbi->one_comp.obj);
748         sbi->oc.single_comp = EC_SINGLE_COMP;
749         sbi->oc.comps = &sbi->one_comp;
750
751         /* fill in some other data by hand */
752         memset(sb->s_id, 0, sizeof(sb->s_id));
753         strcpy(sb->s_id, "exofs");
754         sb->s_blocksize = EXOFS_BLKSIZE;
755         sb->s_blocksize_bits = EXOFS_BLKSHIFT;
756         sb->s_maxbytes = MAX_LFS_FILESIZE;
757         sb->s_max_links = EXOFS_LINK_MAX;
758         atomic_set(&sbi->s_curr_pending, 0);
759         sb->s_bdev = NULL;
760         sb->s_dev = 0;
761
762         comp.obj.partition = sbi->one_comp.obj.partition;
763         comp.obj.id = EXOFS_SUPER_ID;
764         exofs_make_credential(comp.cred, &comp.obj);
765
766         ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb, sizeof(fscb));
767         if (unlikely(ret))
768                 goto free_sbi;
769
770         sb->s_magic = le16_to_cpu(fscb.s_magic);
771         /* NOTE: we read below to be backward compatible with old versions */
772         sbi->s_nextid = le64_to_cpu(fscb.s_nextid);
773         sbi->s_numfiles = le32_to_cpu(fscb.s_numfiles);
774
775         /* make sure what we read from the object store is correct */
776         if (sb->s_magic != EXOFS_SUPER_MAGIC) {
777                 if (!silent)
778                         EXOFS_ERR("ERROR: Bad magic value\n");
779                 ret = -EINVAL;
780                 goto free_sbi;
781         }
782         if (le32_to_cpu(fscb.s_version) > EXOFS_FSCB_VER) {
783                 EXOFS_ERR("ERROR: Bad FSCB version expected-%d got-%d\n",
784                           EXOFS_FSCB_VER, le32_to_cpu(fscb.s_version));
785                 ret = -EINVAL;
786                 goto free_sbi;
787         }
788
789         /* start generation numbers from a random point */
790         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
791         spin_lock_init(&sbi->s_next_gen_lock);
792
793         table_count = le64_to_cpu(fscb.s_dev_table_count);
794         if (table_count) {
795                 ret = exofs_read_lookup_dev_table(sbi, od, table_count);
796                 if (unlikely(ret))
797                         goto free_sbi;
798         } else {
799                 struct exofs_dev *eds;
800
801                 ret = __alloc_dev_table(sbi, 1, &eds);
802                 if (unlikely(ret))
803                         goto free_sbi;
804
805                 ore_comp_set_dev(&sbi->oc, 0, od);
806                 sbi->oc.numdevs = 1;
807         }
808
809         __sbi_read_stats(sbi);
810
811         /* set up operation vectors */
812         ret = super_setup_bdi(sb);
813         if (ret) {
814                 EXOFS_DBGMSG("Failed to super_setup_bdi\n");
815                 goto free_sbi;
816         }
817         sb->s_bdi->ra_pages = __ra_pages(&sbi->layout);
818         sb->s_fs_info = sbi;
819         sb->s_op = &exofs_sops;
820         sb->s_export_op = &exofs_export_ops;
821         root = exofs_iget(sb, EXOFS_ROOT_ID - EXOFS_OBJ_OFF);
822         if (IS_ERR(root)) {
823                 EXOFS_ERR("ERROR: exofs_iget failed\n");
824                 ret = PTR_ERR(root);
825                 goto free_sbi;
826         }
827         sb->s_root = d_make_root(root);
828         if (!sb->s_root) {
829                 EXOFS_ERR("ERROR: get root inode failed\n");
830                 ret = -ENOMEM;
831                 goto free_sbi;
832         }
833
834         if (!S_ISDIR(root->i_mode)) {
835                 dput(sb->s_root);
836                 sb->s_root = NULL;
837                 EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
838                        root->i_mode);
839                 ret = -EINVAL;
840                 goto free_sbi;
841         }
842
843         exofs_sysfs_dbg_print();
844         _exofs_print_device("Mounting", opts->dev_name,
845                             ore_comp_dev(&sbi->oc, 0),
846                             sbi->one_comp.obj.partition);
847         return 0;
848
849 free_sbi:
850         EXOFS_ERR("Unable to mount exofs on %s pid=0x%llx err=%d\n",
851                   opts->dev_name, sbi->one_comp.obj.partition, ret);
852         exofs_free_sbi(sbi);
853         return ret;
854 }
855
856 /*
857  * Set up the superblock (calls exofs_fill_super eventually)
858  */
859 static struct dentry *exofs_mount(struct file_system_type *type,
860                           int flags, const char *dev_name,
861                           void *data)
862 {
863         struct super_block *s;
864         struct exofs_mountopt opts;
865         struct exofs_sb_info *sbi;
866         int ret;
867
868         ret = parse_options(data, &opts);
869         if (ret) {
870                 kfree(opts.dev_name);
871                 return ERR_PTR(ret);
872         }
873
874         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
875         if (!sbi) {
876                 kfree(opts.dev_name);
877                 return ERR_PTR(-ENOMEM);
878         }
879
880         s = sget(type, NULL, set_anon_super, flags, NULL);
881
882         if (IS_ERR(s)) {
883                 kfree(opts.dev_name);
884                 kfree(sbi);
885                 return ERR_CAST(s);
886         }
887
888         if (!opts.dev_name)
889                 opts.dev_name = dev_name;
890
891
892         ret = exofs_fill_super(s, &opts, sbi, flags & SB_SILENT ? 1 : 0);
893         if (ret) {
894                 deactivate_locked_super(s);
895                 return ERR_PTR(ret);
896         }
897         s->s_flags |= SB_ACTIVE;
898         return dget(s->s_root);
899 }
900
901 /*
902  * Return information about the file system state in the buffer.  This is used
903  * by the 'df' command, for example.
904  */
905 static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
906 {
907         struct super_block *sb = dentry->d_sb;
908         struct exofs_sb_info *sbi = sb->s_fs_info;
909         struct ore_io_state *ios;
910         struct osd_attr attrs[] = {
911                 ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
912                         OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
913                 ATTR_DEF(OSD_APAGE_PARTITION_INFORMATION,
914                         OSD_ATTR_PI_USED_CAPACITY, sizeof(__be64)),
915         };
916         uint64_t capacity = ULLONG_MAX;
917         uint64_t used = ULLONG_MAX;
918         int ret;
919
920         ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
921         if (ret) {
922                 EXOFS_DBGMSG("ore_get_io_state failed.\n");
923                 return ret;
924         }
925
926         ios->in_attr = attrs;
927         ios->in_attr_len = ARRAY_SIZE(attrs);
928
929         ret = ore_read(ios);
930         if (unlikely(ret))
931                 goto out;
932
933         ret = extract_attr_from_ios(ios, &attrs[0]);
934         if (likely(!ret)) {
935                 capacity = get_unaligned_be64(attrs[0].val_ptr);
936                 if (unlikely(!capacity))
937                         capacity = ULLONG_MAX;
938         } else
939                 EXOFS_DBGMSG("exofs_statfs: get capacity failed.\n");
940
941         ret = extract_attr_from_ios(ios, &attrs[1]);
942         if (likely(!ret))
943                 used = get_unaligned_be64(attrs[1].val_ptr);
944         else
945                 EXOFS_DBGMSG("exofs_statfs: get used-space failed.\n");
946
947         /* fill in the stats buffer */
948         buf->f_type = EXOFS_SUPER_MAGIC;
949         buf->f_bsize = EXOFS_BLKSIZE;
950         buf->f_blocks = capacity >> 9;
951         buf->f_bfree = (capacity - used) >> 9;
952         buf->f_bavail = buf->f_bfree;
953         buf->f_files = sbi->s_numfiles;
954         buf->f_ffree = EXOFS_MAX_ID - sbi->s_numfiles;
955         buf->f_namelen = EXOFS_NAME_LEN;
956
957 out:
958         ore_put_io_state(ios);
959         return ret;
960 }
961
962 static const struct super_operations exofs_sops = {
963         .alloc_inode    = exofs_alloc_inode,
964         .destroy_inode  = exofs_destroy_inode,
965         .write_inode    = exofs_write_inode,
966         .evict_inode    = exofs_evict_inode,
967         .put_super      = exofs_put_super,
968         .sync_fs        = exofs_sync_fs,
969         .statfs         = exofs_statfs,
970 };
971
972 /******************************************************************************
973  * EXPORT OPERATIONS
974  *****************************************************************************/
975
976 static struct dentry *exofs_get_parent(struct dentry *child)
977 {
978         unsigned long ino = exofs_parent_ino(child);
979
980         if (!ino)
981                 return ERR_PTR(-ESTALE);
982
983         return d_obtain_alias(exofs_iget(child->d_sb, ino));
984 }
985
986 static struct inode *exofs_nfs_get_inode(struct super_block *sb,
987                 u64 ino, u32 generation)
988 {
989         struct inode *inode;
990
991         inode = exofs_iget(sb, ino);
992         if (IS_ERR(inode))
993                 return ERR_CAST(inode);
994         if (generation && inode->i_generation != generation) {
995                 /* we didn't find the right inode.. */
996                 iput(inode);
997                 return ERR_PTR(-ESTALE);
998         }
999         return inode;
1000 }
1001
1002 static struct dentry *exofs_fh_to_dentry(struct super_block *sb,
1003                                 struct fid *fid, int fh_len, int fh_type)
1004 {
1005         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1006                                     exofs_nfs_get_inode);
1007 }
1008
1009 static struct dentry *exofs_fh_to_parent(struct super_block *sb,
1010                                 struct fid *fid, int fh_len, int fh_type)
1011 {
1012         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1013                                     exofs_nfs_get_inode);
1014 }
1015
1016 static const struct export_operations exofs_export_ops = {
1017         .fh_to_dentry = exofs_fh_to_dentry,
1018         .fh_to_parent = exofs_fh_to_parent,
1019         .get_parent = exofs_get_parent,
1020 };
1021
1022 /******************************************************************************
1023  * INSMOD/RMMOD
1024  *****************************************************************************/
1025
1026 /*
1027  * struct that describes this file system
1028  */
1029 static struct file_system_type exofs_type = {
1030         .owner          = THIS_MODULE,
1031         .name           = "exofs",
1032         .mount          = exofs_mount,
1033         .kill_sb        = generic_shutdown_super,
1034 };
1035 MODULE_ALIAS_FS("exofs");
1036
1037 static int __init init_exofs(void)
1038 {
1039         int err;
1040
1041         err = init_inodecache();
1042         if (err)
1043                 goto out;
1044
1045         err = register_filesystem(&exofs_type);
1046         if (err)
1047                 goto out_d;
1048
1049         /* We don't fail if sysfs creation failed */
1050         exofs_sysfs_init();
1051
1052         return 0;
1053 out_d:
1054         destroy_inodecache();
1055 out:
1056         return err;
1057 }
1058
1059 static void __exit exit_exofs(void)
1060 {
1061         exofs_sysfs_uninit();
1062         unregister_filesystem(&exofs_type);
1063         destroy_inodecache();
1064 }
1065
1066 MODULE_AUTHOR("Avishay Traeger <avishay@gmail.com>");
1067 MODULE_DESCRIPTION("exofs");
1068 MODULE_LICENSE("GPL");
1069
1070 module_init(init_exofs)
1071 module_exit(exit_exofs)