GFS2: Fix use-after-free bug on umount
[linux-2.6.git] / fs / gfs2 / ops_fstype.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/blkdev.h>
16 #include <linux/kthread.h>
17 #include <linux/namei.h>
18 #include <linux/mount.h>
19 #include <linux/gfs2_ondisk.h>
20 #include <linux/lm_interface.h>
21
22 #include "gfs2.h"
23 #include "incore.h"
24 #include "bmap.h"
25 #include "glock.h"
26 #include "glops.h"
27 #include "inode.h"
28 #include "mount.h"
29 #include "recovery.h"
30 #include "rgrp.h"
31 #include "super.h"
32 #include "sys.h"
33 #include "util.h"
34 #include "log.h"
35 #include "quota.h"
36 #include "dir.h"
37
38 #define DO 0
39 #define UNDO 1
40
41 static const u32 gfs2_old_fs_formats[] = {
42         0
43 };
44
45 static const u32 gfs2_old_multihost_formats[] = {
46         0
47 };
48
49 /**
50  * gfs2_tune_init - Fill a gfs2_tune structure with default values
51  * @gt: tune
52  *
53  */
54
55 static void gfs2_tune_init(struct gfs2_tune *gt)
56 {
57         spin_lock_init(&gt->gt_spin);
58
59         gt->gt_incore_log_blocks = 1024;
60         gt->gt_log_flush_secs = 60;
61         gt->gt_recoverd_secs = 60;
62         gt->gt_logd_secs = 1;
63         gt->gt_quota_simul_sync = 64;
64         gt->gt_quota_warn_period = 10;
65         gt->gt_quota_scale_num = 1;
66         gt->gt_quota_scale_den = 1;
67         gt->gt_quota_cache_secs = 300;
68         gt->gt_quota_quantum = 60;
69         gt->gt_new_files_jdata = 0;
70         gt->gt_max_readahead = 1 << 18;
71         gt->gt_stall_secs = 600;
72         gt->gt_complain_secs = 10;
73         gt->gt_statfs_quantum = 30;
74         gt->gt_statfs_slow = 0;
75 }
76
77 static struct gfs2_sbd *init_sbd(struct super_block *sb)
78 {
79         struct gfs2_sbd *sdp;
80
81         sdp = kzalloc(sizeof(struct gfs2_sbd), GFP_KERNEL);
82         if (!sdp)
83                 return NULL;
84
85         sb->s_fs_info = sdp;
86         sdp->sd_vfs = sb;
87
88         gfs2_tune_init(&sdp->sd_tune);
89
90         mutex_init(&sdp->sd_inum_mutex);
91         spin_lock_init(&sdp->sd_statfs_spin);
92
93         spin_lock_init(&sdp->sd_rindex_spin);
94         mutex_init(&sdp->sd_rindex_mutex);
95         INIT_LIST_HEAD(&sdp->sd_rindex_list);
96         INIT_LIST_HEAD(&sdp->sd_rindex_mru_list);
97
98         INIT_LIST_HEAD(&sdp->sd_jindex_list);
99         spin_lock_init(&sdp->sd_jindex_spin);
100         mutex_init(&sdp->sd_jindex_mutex);
101
102         INIT_LIST_HEAD(&sdp->sd_quota_list);
103         spin_lock_init(&sdp->sd_quota_spin);
104         mutex_init(&sdp->sd_quota_mutex);
105         init_waitqueue_head(&sdp->sd_quota_wait);
106         INIT_LIST_HEAD(&sdp->sd_trunc_list);
107         spin_lock_init(&sdp->sd_trunc_lock);
108
109         spin_lock_init(&sdp->sd_log_lock);
110
111         INIT_LIST_HEAD(&sdp->sd_log_le_buf);
112         INIT_LIST_HEAD(&sdp->sd_log_le_revoke);
113         INIT_LIST_HEAD(&sdp->sd_log_le_rg);
114         INIT_LIST_HEAD(&sdp->sd_log_le_databuf);
115         INIT_LIST_HEAD(&sdp->sd_log_le_ordered);
116
117         mutex_init(&sdp->sd_log_reserve_mutex);
118         INIT_LIST_HEAD(&sdp->sd_ail1_list);
119         INIT_LIST_HEAD(&sdp->sd_ail2_list);
120
121         init_rwsem(&sdp->sd_log_flush_lock);
122         atomic_set(&sdp->sd_log_in_flight, 0);
123         init_waitqueue_head(&sdp->sd_log_flush_wait);
124
125         INIT_LIST_HEAD(&sdp->sd_revoke_list);
126
127         mutex_init(&sdp->sd_freeze_lock);
128
129         return sdp;
130 }
131
132
133 /**
134  * gfs2_check_sb - Check superblock
135  * @sdp: the filesystem
136  * @sb: The superblock
137  * @silent: Don't print a message if the check fails
138  *
139  * Checks the version code of the FS is one that we understand how to
140  * read and that the sizes of the various on-disk structures have not
141  * changed.
142  */
143
144 static int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb_host *sb, int silent)
145 {
146         unsigned int x;
147
148         if (sb->sb_magic != GFS2_MAGIC ||
149             sb->sb_type != GFS2_METATYPE_SB) {
150                 if (!silent)
151                         printk(KERN_WARNING "GFS2: not a GFS2 filesystem\n");
152                 return -EINVAL;
153         }
154
155         /*  If format numbers match exactly, we're done.  */
156
157         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
158             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
159                 return 0;
160
161         if (sb->sb_fs_format != GFS2_FORMAT_FS) {
162                 for (x = 0; gfs2_old_fs_formats[x]; x++)
163                         if (gfs2_old_fs_formats[x] == sb->sb_fs_format)
164                                 break;
165
166                 if (!gfs2_old_fs_formats[x]) {
167                         printk(KERN_WARNING
168                                "GFS2: code version (%u, %u) is incompatible "
169                                "with ondisk format (%u, %u)\n",
170                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
171                                sb->sb_fs_format, sb->sb_multihost_format);
172                         printk(KERN_WARNING
173                                "GFS2: I don't know how to upgrade this FS\n");
174                         return -EINVAL;
175                 }
176         }
177
178         if (sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
179                 for (x = 0; gfs2_old_multihost_formats[x]; x++)
180                         if (gfs2_old_multihost_formats[x] ==
181                             sb->sb_multihost_format)
182                                 break;
183
184                 if (!gfs2_old_multihost_formats[x]) {
185                         printk(KERN_WARNING
186                                "GFS2: code version (%u, %u) is incompatible "
187                                "with ondisk format (%u, %u)\n",
188                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
189                                sb->sb_fs_format, sb->sb_multihost_format);
190                         printk(KERN_WARNING
191                                "GFS2: I don't know how to upgrade this FS\n");
192                         return -EINVAL;
193                 }
194         }
195
196         if (!sdp->sd_args.ar_upgrade) {
197                 printk(KERN_WARNING
198                        "GFS2: code version (%u, %u) is incompatible "
199                        "with ondisk format (%u, %u)\n",
200                        GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
201                        sb->sb_fs_format, sb->sb_multihost_format);
202                 printk(KERN_INFO
203                        "GFS2: Use the \"upgrade\" mount option to upgrade "
204                        "the FS\n");
205                 printk(KERN_INFO "GFS2: See the manual for more details\n");
206                 return -EINVAL;
207         }
208
209         return 0;
210 }
211
212 static void end_bio_io_page(struct bio *bio, int error)
213 {
214         struct page *page = bio->bi_private;
215
216         if (!error)
217                 SetPageUptodate(page);
218         else
219                 printk(KERN_WARNING "gfs2: error %d reading superblock\n", error);
220         unlock_page(page);
221 }
222
223 static void gfs2_sb_in(struct gfs2_sb_host *sb, const void *buf)
224 {
225         const struct gfs2_sb *str = buf;
226
227         sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
228         sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
229         sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
230         sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
231         sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
232         sb->sb_bsize = be32_to_cpu(str->sb_bsize);
233         sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
234         sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
235         sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
236         sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
237         sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
238
239         memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
240         memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
241 }
242
243 /**
244  * gfs2_read_super - Read the gfs2 super block from disk
245  * @sdp: The GFS2 super block
246  * @sector: The location of the super block
247  * @error: The error code to return
248  *
249  * This uses the bio functions to read the super block from disk
250  * because we want to be 100% sure that we never read cached data.
251  * A super block is read twice only during each GFS2 mount and is
252  * never written to by the filesystem. The first time its read no
253  * locks are held, and the only details which are looked at are those
254  * relating to the locking protocol. Once locking is up and working,
255  * the sb is read again under the lock to establish the location of
256  * the master directory (contains pointers to journals etc) and the
257  * root directory.
258  *
259  * Returns: 0 on success or error
260  */
261
262 static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector)
263 {
264         struct super_block *sb = sdp->sd_vfs;
265         struct gfs2_sb *p;
266         struct page *page;
267         struct bio *bio;
268
269         page = alloc_page(GFP_NOFS);
270         if (unlikely(!page))
271                 return -ENOBUFS;
272
273         ClearPageUptodate(page);
274         ClearPageDirty(page);
275         lock_page(page);
276
277         bio = bio_alloc(GFP_NOFS, 1);
278         if (unlikely(!bio)) {
279                 __free_page(page);
280                 return -ENOBUFS;
281         }
282
283         bio->bi_sector = sector * (sb->s_blocksize >> 9);
284         bio->bi_bdev = sb->s_bdev;
285         bio_add_page(bio, page, PAGE_SIZE, 0);
286
287         bio->bi_end_io = end_bio_io_page;
288         bio->bi_private = page;
289         submit_bio(READ_SYNC | (1 << BIO_RW_META), bio);
290         wait_on_page_locked(page);
291         bio_put(bio);
292         if (!PageUptodate(page)) {
293                 __free_page(page);
294                 return -EIO;
295         }
296         p = kmap(page);
297         gfs2_sb_in(&sdp->sd_sb, p);
298         kunmap(page);
299         __free_page(page);
300         return 0;
301 }
302 /**
303  * gfs2_read_sb - Read super block
304  * @sdp: The GFS2 superblock
305  * @gl: the glock for the superblock (assumed to be held)
306  * @silent: Don't print message if mount fails
307  *
308  */
309
310 static int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
311 {
312         u32 hash_blocks, ind_blocks, leaf_blocks;
313         u32 tmp_blocks;
314         unsigned int x;
315         int error;
316
317         error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
318         if (error) {
319                 if (!silent)
320                         fs_err(sdp, "can't read superblock\n");
321                 return error;
322         }
323
324         error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
325         if (error)
326                 return error;
327
328         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
329                                GFS2_BASIC_BLOCK_SHIFT;
330         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
331         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
332                           sizeof(struct gfs2_dinode)) / sizeof(u64);
333         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
334                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
335         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
336         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
337         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
338         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
339         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
340                                 sizeof(struct gfs2_meta_header)) /
341                                 sizeof(struct gfs2_quota_change);
342
343         /* Compute maximum reservation required to add a entry to a directory */
344
345         hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << GFS2_DIR_MAX_DEPTH),
346                              sdp->sd_jbsize);
347
348         ind_blocks = 0;
349         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
350                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
351                 ind_blocks += tmp_blocks;
352         }
353
354         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
355
356         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
357
358         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
359                                 sizeof(struct gfs2_dinode);
360         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
361         for (x = 2;; x++) {
362                 u64 space, d;
363                 u32 m;
364
365                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
366                 d = space;
367                 m = do_div(d, sdp->sd_inptrs);
368
369                 if (d != sdp->sd_heightsize[x - 1] || m)
370                         break;
371                 sdp->sd_heightsize[x] = space;
372         }
373         sdp->sd_max_height = x;
374         sdp->sd_heightsize[x] = ~0;
375         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
376
377         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
378                                  sizeof(struct gfs2_dinode);
379         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
380         for (x = 2;; x++) {
381                 u64 space, d;
382                 u32 m;
383
384                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
385                 d = space;
386                 m = do_div(d, sdp->sd_inptrs);
387
388                 if (d != sdp->sd_jheightsize[x - 1] || m)
389                         break;
390                 sdp->sd_jheightsize[x] = space;
391         }
392         sdp->sd_max_jheight = x;
393         sdp->sd_jheightsize[x] = ~0;
394         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
395
396         return 0;
397 }
398
399 static int init_names(struct gfs2_sbd *sdp, int silent)
400 {
401         char *proto, *table;
402         int error = 0;
403
404         proto = sdp->sd_args.ar_lockproto;
405         table = sdp->sd_args.ar_locktable;
406
407         /*  Try to autodetect  */
408
409         if (!proto[0] || !table[0]) {
410                 error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
411                 if (error)
412                         return error;
413
414                 error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
415                 if (error)
416                         goto out;
417
418                 if (!proto[0])
419                         proto = sdp->sd_sb.sb_lockproto;
420                 if (!table[0])
421                         table = sdp->sd_sb.sb_locktable;
422         }
423
424         if (!table[0])
425                 table = sdp->sd_vfs->s_id;
426
427         strlcpy(sdp->sd_proto_name, proto, GFS2_FSNAME_LEN);
428         strlcpy(sdp->sd_table_name, table, GFS2_FSNAME_LEN);
429
430         table = sdp->sd_table_name;
431         while ((table = strchr(table, '/')))
432                 *table = '_';
433
434 out:
435         return error;
436 }
437
438 static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
439                         int undo)
440 {
441         int error = 0;
442
443         if (undo)
444                 goto fail_trans;
445
446         error = gfs2_glock_nq_num(sdp,
447                                   GFS2_MOUNT_LOCK, &gfs2_nondisk_glops,
448                                   LM_ST_EXCLUSIVE, LM_FLAG_NOEXP | GL_NOCACHE,
449                                   mount_gh);
450         if (error) {
451                 fs_err(sdp, "can't acquire mount glock: %d\n", error);
452                 goto fail;
453         }
454
455         error = gfs2_glock_nq_num(sdp,
456                                   GFS2_LIVE_LOCK, &gfs2_nondisk_glops,
457                                   LM_ST_SHARED,
458                                   LM_FLAG_NOEXP | GL_EXACT,
459                                   &sdp->sd_live_gh);
460         if (error) {
461                 fs_err(sdp, "can't acquire live glock: %d\n", error);
462                 goto fail_mount;
463         }
464
465         error = gfs2_glock_get(sdp, GFS2_RENAME_LOCK, &gfs2_nondisk_glops,
466                                CREATE, &sdp->sd_rename_gl);
467         if (error) {
468                 fs_err(sdp, "can't create rename glock: %d\n", error);
469                 goto fail_live;
470         }
471
472         error = gfs2_glock_get(sdp, GFS2_TRANS_LOCK, &gfs2_trans_glops,
473                                CREATE, &sdp->sd_trans_gl);
474         if (error) {
475                 fs_err(sdp, "can't create transaction glock: %d\n", error);
476                 goto fail_rename;
477         }
478
479         return 0;
480
481 fail_trans:
482         gfs2_glock_put(sdp->sd_trans_gl);
483 fail_rename:
484         gfs2_glock_put(sdp->sd_rename_gl);
485 fail_live:
486         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
487 fail_mount:
488         gfs2_glock_dq_uninit(mount_gh);
489 fail:
490         return error;
491 }
492
493 static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
494                             u64 no_addr, const char *name)
495 {
496         struct gfs2_sbd *sdp = sb->s_fs_info;
497         struct dentry *dentry;
498         struct inode *inode;
499
500         inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0, 0);
501         if (IS_ERR(inode)) {
502                 fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
503                 return PTR_ERR(inode);
504         }
505         dentry = d_alloc_root(inode);
506         if (!dentry) {
507                 fs_err(sdp, "can't alloc %s dentry\n", name);
508                 iput(inode);
509                 return -ENOMEM;
510         }
511         dentry->d_op = &gfs2_dops;
512         *dptr = dentry;
513         return 0;
514 }
515
516 static int init_sb(struct gfs2_sbd *sdp, int silent)
517 {
518         struct super_block *sb = sdp->sd_vfs;
519         struct gfs2_holder sb_gh;
520         u64 no_addr;
521         int ret;
522
523         ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
524                                 LM_ST_SHARED, 0, &sb_gh);
525         if (ret) {
526                 fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
527                 return ret;
528         }
529
530         ret = gfs2_read_sb(sdp, sb_gh.gh_gl, silent);
531         if (ret) {
532                 fs_err(sdp, "can't read superblock: %d\n", ret);
533                 goto out;
534         }
535
536         /* Set up the buffer cache and SB for real */
537         if (sdp->sd_sb.sb_bsize < bdev_hardsect_size(sb->s_bdev)) {
538                 ret = -EINVAL;
539                 fs_err(sdp, "FS block size (%u) is too small for device "
540                        "block size (%u)\n",
541                        sdp->sd_sb.sb_bsize, bdev_hardsect_size(sb->s_bdev));
542                 goto out;
543         }
544         if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
545                 ret = -EINVAL;
546                 fs_err(sdp, "FS block size (%u) is too big for machine "
547                        "page size (%u)\n",
548                        sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
549                 goto out;
550         }
551         sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
552
553         /* Get the root inode */
554         no_addr = sdp->sd_sb.sb_root_dir.no_addr;
555         ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
556         if (ret)
557                 goto out;
558
559         /* Get the master inode */
560         no_addr = sdp->sd_sb.sb_master_dir.no_addr;
561         ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
562         if (ret) {
563                 dput(sdp->sd_root_dir);
564                 goto out;
565         }
566         sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
567 out:
568         gfs2_glock_dq_uninit(&sb_gh);
569         return ret;
570 }
571
572 /**
573  * map_journal_extents - create a reusable "extent" mapping from all logical
574  * blocks to all physical blocks for the given journal.  This will save
575  * us time when writing journal blocks.  Most journals will have only one
576  * extent that maps all their logical blocks.  That's because gfs2.mkfs
577  * arranges the journal blocks sequentially to maximize performance.
578  * So the extent would map the first block for the entire file length.
579  * However, gfs2_jadd can happen while file activity is happening, so
580  * those journals may not be sequential.  Less likely is the case where
581  * the users created their own journals by mounting the metafs and
582  * laying it out.  But it's still possible.  These journals might have
583  * several extents.
584  *
585  * TODO: This should be done in bigger chunks rather than one block at a time,
586  *       but since it's only done at mount time, I'm not worried about the
587  *       time it takes.
588  */
589 static int map_journal_extents(struct gfs2_sbd *sdp)
590 {
591         struct gfs2_jdesc *jd = sdp->sd_jdesc;
592         unsigned int lb;
593         u64 db, prev_db; /* logical block, disk block, prev disk block */
594         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
595         struct gfs2_journal_extent *jext = NULL;
596         struct buffer_head bh;
597         int rc = 0;
598
599         prev_db = 0;
600
601         for (lb = 0; lb < ip->i_disksize >> sdp->sd_sb.sb_bsize_shift; lb++) {
602                 bh.b_state = 0;
603                 bh.b_blocknr = 0;
604                 bh.b_size = 1 << ip->i_inode.i_blkbits;
605                 rc = gfs2_block_map(jd->jd_inode, lb, &bh, 0);
606                 db = bh.b_blocknr;
607                 if (rc || !db) {
608                         printk(KERN_INFO "GFS2 journal mapping error %d: lb="
609                                "%u db=%llu\n", rc, lb, (unsigned long long)db);
610                         break;
611                 }
612                 if (!prev_db || db != prev_db + 1) {
613                         jext = kzalloc(sizeof(struct gfs2_journal_extent),
614                                        GFP_KERNEL);
615                         if (!jext) {
616                                 printk(KERN_INFO "GFS2 error: out of memory "
617                                        "mapping journal extents.\n");
618                                 rc = -ENOMEM;
619                                 break;
620                         }
621                         jext->dblock = db;
622                         jext->lblock = lb;
623                         jext->blocks = 1;
624                         list_add_tail(&jext->extent_list, &jd->extent_list);
625                 } else {
626                         jext->blocks++;
627                 }
628                 prev_db = db;
629         }
630         return rc;
631 }
632
633 static void gfs2_lm_others_may_mount(struct gfs2_sbd *sdp)
634 {
635         if (!sdp->sd_lockstruct.ls_ops->lm_others_may_mount)
636                 return;
637         if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
638                 sdp->sd_lockstruct.ls_ops->lm_others_may_mount(
639                                         sdp->sd_lockstruct.ls_lockspace);
640 }
641
642 /**
643  * gfs2_jindex_hold - Grab a lock on the jindex
644  * @sdp: The GFS2 superblock
645  * @ji_gh: the holder for the jindex glock
646  *
647  * Returns: errno
648  */
649
650 static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
651 {
652         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
653         struct qstr name;
654         char buf[20];
655         struct gfs2_jdesc *jd;
656         int error;
657
658         name.name = buf;
659
660         mutex_lock(&sdp->sd_jindex_mutex);
661
662         for (;;) {
663                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
664                 if (error)
665                         break;
666
667                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
668                 name.hash = gfs2_disk_hash(name.name, name.len);
669
670                 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
671                 if (error == -ENOENT) {
672                         error = 0;
673                         break;
674                 }
675
676                 gfs2_glock_dq_uninit(ji_gh);
677
678                 if (error)
679                         break;
680
681                 error = -ENOMEM;
682                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
683                 if (!jd)
684                         break;
685
686                 INIT_LIST_HEAD(&jd->extent_list);
687                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
688                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
689                         if (!jd->jd_inode)
690                                 error = -ENOENT;
691                         else
692                                 error = PTR_ERR(jd->jd_inode);
693                         kfree(jd);
694                         break;
695                 }
696
697                 spin_lock(&sdp->sd_jindex_spin);
698                 jd->jd_jid = sdp->sd_journals++;
699                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
700                 spin_unlock(&sdp->sd_jindex_spin);
701         }
702
703         mutex_unlock(&sdp->sd_jindex_mutex);
704
705         return error;
706 }
707
708 /**
709  * gfs2_jindex_free - Clear all the journal index information
710  * @sdp: The GFS2 superblock
711  *
712  */
713
714 static void gfs2_jindex_free(struct gfs2_sbd *sdp)
715 {
716         struct list_head list, *head;
717         struct gfs2_jdesc *jd;
718         struct gfs2_journal_extent *jext;
719
720         spin_lock(&sdp->sd_jindex_spin);
721         list_add(&list, &sdp->sd_jindex_list);
722         list_del_init(&sdp->sd_jindex_list);
723         sdp->sd_journals = 0;
724         spin_unlock(&sdp->sd_jindex_spin);
725
726         while (!list_empty(&list)) {
727                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
728                 head = &jd->extent_list;
729                 while (!list_empty(head)) {
730                         jext = list_entry(head->next,
731                                           struct gfs2_journal_extent,
732                                           extent_list);
733                         list_del(&jext->extent_list);
734                         kfree(jext);
735                 }
736                 list_del(&jd->jd_list);
737                 iput(jd->jd_inode);
738                 kfree(jd);
739         }
740 }
741
742 static int init_journal(struct gfs2_sbd *sdp, int undo)
743 {
744         struct inode *master = sdp->sd_master_dir->d_inode;
745         struct gfs2_holder ji_gh;
746         struct task_struct *p;
747         struct gfs2_inode *ip;
748         int jindex = 1;
749         int error = 0;
750
751         if (undo) {
752                 jindex = 0;
753                 goto fail_recoverd;
754         }
755
756         sdp->sd_jindex = gfs2_lookup_simple(master, "jindex");
757         if (IS_ERR(sdp->sd_jindex)) {
758                 fs_err(sdp, "can't lookup journal index: %d\n", error);
759                 return PTR_ERR(sdp->sd_jindex);
760         }
761         ip = GFS2_I(sdp->sd_jindex);
762
763         /* Load in the journal index special file */
764
765         error = gfs2_jindex_hold(sdp, &ji_gh);
766         if (error) {
767                 fs_err(sdp, "can't read journal index: %d\n", error);
768                 goto fail;
769         }
770
771         error = -EINVAL;
772         if (!gfs2_jindex_size(sdp)) {
773                 fs_err(sdp, "no journals!\n");
774                 goto fail_jindex;
775         }
776
777         if (sdp->sd_args.ar_spectator) {
778                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
779                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
780         } else {
781                 if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
782                         fs_err(sdp, "can't mount journal #%u\n",
783                                sdp->sd_lockstruct.ls_jid);
784                         fs_err(sdp, "there are only %u journals (0 - %u)\n",
785                                gfs2_jindex_size(sdp),
786                                gfs2_jindex_size(sdp) - 1);
787                         goto fail_jindex;
788                 }
789                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);
790
791                 error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
792                                           &gfs2_journal_glops,
793                                           LM_ST_EXCLUSIVE, LM_FLAG_NOEXP,
794                                           &sdp->sd_journal_gh);
795                 if (error) {
796                         fs_err(sdp, "can't acquire journal glock: %d\n", error);
797                         goto fail_jindex;
798                 }
799
800                 ip = GFS2_I(sdp->sd_jdesc->jd_inode);
801                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
802                                            LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE,
803                                            &sdp->sd_jinode_gh);
804                 if (error) {
805                         fs_err(sdp, "can't acquire journal inode glock: %d\n",
806                                error);
807                         goto fail_journal_gh;
808                 }
809
810                 error = gfs2_jdesc_check(sdp->sd_jdesc);
811                 if (error) {
812                         fs_err(sdp, "my journal (%u) is bad: %d\n",
813                                sdp->sd_jdesc->jd_jid, error);
814                         goto fail_jinode_gh;
815                 }
816                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
817
818                 /* Map the extents for this journal's blocks */
819                 map_journal_extents(sdp);
820         }
821
822         if (sdp->sd_lockstruct.ls_first) {
823                 unsigned int x;
824                 for (x = 0; x < sdp->sd_journals; x++) {
825                         error = gfs2_recover_journal(gfs2_jdesc_find(sdp, x));
826                         if (error) {
827                                 fs_err(sdp, "error recovering journal %u: %d\n",
828                                        x, error);
829                                 goto fail_jinode_gh;
830                         }
831                 }
832
833                 gfs2_lm_others_may_mount(sdp);
834         } else if (!sdp->sd_args.ar_spectator) {
835                 error = gfs2_recover_journal(sdp->sd_jdesc);
836                 if (error) {
837                         fs_err(sdp, "error recovering my journal: %d\n", error);
838                         goto fail_jinode_gh;
839                 }
840         }
841
842         set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
843         gfs2_glock_dq_uninit(&ji_gh);
844         jindex = 0;
845
846         p = kthread_run(gfs2_recoverd, sdp, "gfs2_recoverd");
847         error = IS_ERR(p);
848         if (error) {
849                 fs_err(sdp, "can't start recoverd thread: %d\n", error);
850                 goto fail_jinode_gh;
851         }
852         sdp->sd_recoverd_process = p;
853
854         return 0;
855
856 fail_recoverd:
857         kthread_stop(sdp->sd_recoverd_process);
858 fail_jinode_gh:
859         if (!sdp->sd_args.ar_spectator)
860                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
861 fail_journal_gh:
862         if (!sdp->sd_args.ar_spectator)
863                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
864 fail_jindex:
865         gfs2_jindex_free(sdp);
866         if (jindex)
867                 gfs2_glock_dq_uninit(&ji_gh);
868 fail:
869         iput(sdp->sd_jindex);
870         return error;
871 }
872
873
874 static int init_inodes(struct gfs2_sbd *sdp, int undo)
875 {
876         int error = 0;
877         struct gfs2_inode *ip;
878         struct inode *master = sdp->sd_master_dir->d_inode;
879
880         if (undo)
881                 goto fail_qinode;
882
883         error = init_journal(sdp, undo);
884         if (error)
885                 goto fail;
886
887         /* Read in the master inode number inode */
888         sdp->sd_inum_inode = gfs2_lookup_simple(master, "inum");
889         if (IS_ERR(sdp->sd_inum_inode)) {
890                 error = PTR_ERR(sdp->sd_inum_inode);
891                 fs_err(sdp, "can't read in inum inode: %d\n", error);
892                 goto fail_journal;
893         }
894
895
896         /* Read in the master statfs inode */
897         sdp->sd_statfs_inode = gfs2_lookup_simple(master, "statfs");
898         if (IS_ERR(sdp->sd_statfs_inode)) {
899                 error = PTR_ERR(sdp->sd_statfs_inode);
900                 fs_err(sdp, "can't read in statfs inode: %d\n", error);
901                 goto fail_inum;
902         }
903
904         /* Read in the resource index inode */
905         sdp->sd_rindex = gfs2_lookup_simple(master, "rindex");
906         if (IS_ERR(sdp->sd_rindex)) {
907                 error = PTR_ERR(sdp->sd_rindex);
908                 fs_err(sdp, "can't get resource index inode: %d\n", error);
909                 goto fail_statfs;
910         }
911         ip = GFS2_I(sdp->sd_rindex);
912         sdp->sd_rindex_uptodate = 0;
913
914         /* Read in the quota inode */
915         sdp->sd_quota_inode = gfs2_lookup_simple(master, "quota");
916         if (IS_ERR(sdp->sd_quota_inode)) {
917                 error = PTR_ERR(sdp->sd_quota_inode);
918                 fs_err(sdp, "can't get quota file inode: %d\n", error);
919                 goto fail_rindex;
920         }
921         return 0;
922
923 fail_qinode:
924         iput(sdp->sd_quota_inode);
925 fail_rindex:
926         gfs2_clear_rgrpd(sdp);
927         iput(sdp->sd_rindex);
928 fail_statfs:
929         iput(sdp->sd_statfs_inode);
930 fail_inum:
931         iput(sdp->sd_inum_inode);
932 fail_journal:
933         init_journal(sdp, UNDO);
934 fail:
935         return error;
936 }
937
938 static int init_per_node(struct gfs2_sbd *sdp, int undo)
939 {
940         struct inode *pn = NULL;
941         char buf[30];
942         int error = 0;
943         struct gfs2_inode *ip;
944         struct inode *master = sdp->sd_master_dir->d_inode;
945
946         if (sdp->sd_args.ar_spectator)
947                 return 0;
948
949         if (undo)
950                 goto fail_qc_gh;
951
952         pn = gfs2_lookup_simple(master, "per_node");
953         if (IS_ERR(pn)) {
954                 error = PTR_ERR(pn);
955                 fs_err(sdp, "can't find per_node directory: %d\n", error);
956                 return error;
957         }
958
959         sprintf(buf, "inum_range%u", sdp->sd_jdesc->jd_jid);
960         sdp->sd_ir_inode = gfs2_lookup_simple(pn, buf);
961         if (IS_ERR(sdp->sd_ir_inode)) {
962                 error = PTR_ERR(sdp->sd_ir_inode);
963                 fs_err(sdp, "can't find local \"ir\" file: %d\n", error);
964                 goto fail;
965         }
966
967         sprintf(buf, "statfs_change%u", sdp->sd_jdesc->jd_jid);
968         sdp->sd_sc_inode = gfs2_lookup_simple(pn, buf);
969         if (IS_ERR(sdp->sd_sc_inode)) {
970                 error = PTR_ERR(sdp->sd_sc_inode);
971                 fs_err(sdp, "can't find local \"sc\" file: %d\n", error);
972                 goto fail_ir_i;
973         }
974
975         sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
976         sdp->sd_qc_inode = gfs2_lookup_simple(pn, buf);
977         if (IS_ERR(sdp->sd_qc_inode)) {
978                 error = PTR_ERR(sdp->sd_qc_inode);
979                 fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
980                 goto fail_ut_i;
981         }
982
983         iput(pn);
984         pn = NULL;
985
986         ip = GFS2_I(sdp->sd_ir_inode);
987         error = gfs2_glock_nq_init(ip->i_gl,
988                                    LM_ST_EXCLUSIVE, 0,
989                                    &sdp->sd_ir_gh);
990         if (error) {
991                 fs_err(sdp, "can't lock local \"ir\" file: %d\n", error);
992                 goto fail_qc_i;
993         }
994
995         ip = GFS2_I(sdp->sd_sc_inode);
996         error = gfs2_glock_nq_init(ip->i_gl,
997                                    LM_ST_EXCLUSIVE, 0,
998                                    &sdp->sd_sc_gh);
999         if (error) {
1000                 fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
1001                 goto fail_ir_gh;
1002         }
1003
1004         ip = GFS2_I(sdp->sd_qc_inode);
1005         error = gfs2_glock_nq_init(ip->i_gl,
1006                                    LM_ST_EXCLUSIVE, 0,
1007                                    &sdp->sd_qc_gh);
1008         if (error) {
1009                 fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
1010                 goto fail_ut_gh;
1011         }
1012
1013         return 0;
1014
1015 fail_qc_gh:
1016         gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
1017 fail_ut_gh:
1018         gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
1019 fail_ir_gh:
1020         gfs2_glock_dq_uninit(&sdp->sd_ir_gh);
1021 fail_qc_i:
1022         iput(sdp->sd_qc_inode);
1023 fail_ut_i:
1024         iput(sdp->sd_sc_inode);
1025 fail_ir_i:
1026         iput(sdp->sd_ir_inode);
1027 fail:
1028         if (pn)
1029                 iput(pn);
1030         return error;
1031 }
1032
1033 static int init_threads(struct gfs2_sbd *sdp, int undo)
1034 {
1035         struct task_struct *p;
1036         int error = 0;
1037
1038         if (undo)
1039                 goto fail_quotad;
1040
1041         sdp->sd_log_flush_time = jiffies;
1042         sdp->sd_jindex_refresh_time = jiffies;
1043
1044         p = kthread_run(gfs2_logd, sdp, "gfs2_logd");
1045         error = IS_ERR(p);
1046         if (error) {
1047                 fs_err(sdp, "can't start logd thread: %d\n", error);
1048                 return error;
1049         }
1050         sdp->sd_logd_process = p;
1051
1052         p = kthread_run(gfs2_quotad, sdp, "gfs2_quotad");
1053         error = IS_ERR(p);
1054         if (error) {
1055                 fs_err(sdp, "can't start quotad thread: %d\n", error);
1056                 goto fail;
1057         }
1058         sdp->sd_quotad_process = p;
1059
1060         return 0;
1061
1062
1063 fail_quotad:
1064         kthread_stop(sdp->sd_quotad_process);
1065 fail:
1066         kthread_stop(sdp->sd_logd_process);
1067         return error;
1068 }
1069
1070 /**
1071  * gfs2_lm_mount - mount a locking protocol
1072  * @sdp: the filesystem
1073  * @args: mount arguements
1074  * @silent: if 1, don't complain if the FS isn't a GFS2 fs
1075  *
1076  * Returns: errno
1077  */
1078
1079 static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
1080 {
1081         char *proto = sdp->sd_proto_name;
1082         char *table = sdp->sd_table_name;
1083         int flags = LM_MFLAG_CONV_NODROP;
1084         int error;
1085
1086         if (sdp->sd_args.ar_spectator)
1087                 flags |= LM_MFLAG_SPECTATOR;
1088
1089         fs_info(sdp, "Trying to join cluster \"%s\", \"%s\"\n", proto, table);
1090
1091         error = gfs2_mount_lockproto(proto, table, sdp->sd_args.ar_hostdata,
1092                                      gfs2_glock_cb, sdp,
1093                                      GFS2_MIN_LVB_SIZE, flags,
1094                                      &sdp->sd_lockstruct, &sdp->sd_kobj);
1095         if (error) {
1096                 fs_info(sdp, "can't mount proto=%s, table=%s, hostdata=%s\n",
1097                         proto, table, sdp->sd_args.ar_hostdata);
1098                 goto out;
1099         }
1100
1101         if (gfs2_assert_warn(sdp, sdp->sd_lockstruct.ls_ops) ||
1102             gfs2_assert_warn(sdp, sdp->sd_lockstruct.ls_lvb_size >=
1103                                   GFS2_MIN_LVB_SIZE)) {
1104                 gfs2_unmount_lockproto(&sdp->sd_lockstruct);
1105                 goto out;
1106         }
1107
1108         if (sdp->sd_args.ar_spectator)
1109                 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.s", table);
1110         else
1111                 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.%u", table,
1112                          sdp->sd_lockstruct.ls_jid);
1113
1114         fs_info(sdp, "Joined cluster. Now mounting FS...\n");
1115
1116         if ((sdp->sd_lockstruct.ls_flags & LM_LSFLAG_LOCAL) &&
1117             !sdp->sd_args.ar_ignore_local_fs) {
1118                 sdp->sd_args.ar_localflocks = 1;
1119                 sdp->sd_args.ar_localcaching = 1;
1120         }
1121
1122 out:
1123         return error;
1124 }
1125
1126 void gfs2_lm_unmount(struct gfs2_sbd *sdp)
1127 {
1128         if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
1129                 gfs2_unmount_lockproto(&sdp->sd_lockstruct);
1130 }
1131
1132 /**
1133  * fill_super - Read in superblock
1134  * @sb: The VFS superblock
1135  * @data: Mount options
1136  * @silent: Don't complain if it's not a GFS2 filesystem
1137  *
1138  * Returns: errno
1139  */
1140
1141 static int fill_super(struct super_block *sb, void *data, int silent)
1142 {
1143         struct gfs2_sbd *sdp;
1144         struct gfs2_holder mount_gh;
1145         int error;
1146
1147         sdp = init_sbd(sb);
1148         if (!sdp) {
1149                 printk(KERN_WARNING "GFS2: can't alloc struct gfs2_sbd\n");
1150                 return -ENOMEM;
1151         }
1152
1153         error = gfs2_mount_args(sdp, (char *)data, 0);
1154         if (error) {
1155                 printk(KERN_WARNING "GFS2: can't parse mount arguments\n");
1156                 goto fail;
1157         }
1158
1159         sb->s_magic = GFS2_MAGIC;
1160         sb->s_op = &gfs2_super_ops;
1161         sb->s_export_op = &gfs2_export_ops;
1162         sb->s_time_gran = 1;
1163         sb->s_maxbytes = MAX_LFS_FILESIZE;
1164
1165         /* Set up the buffer cache and fill in some fake block size values
1166            to allow us to read-in the on-disk superblock. */
1167         sdp->sd_sb.sb_bsize = sb_min_blocksize(sb, GFS2_BASIC_BLOCK);
1168         sdp->sd_sb.sb_bsize_shift = sb->s_blocksize_bits;
1169         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
1170                                GFS2_BASIC_BLOCK_SHIFT;
1171         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
1172
1173         error = init_names(sdp, silent);
1174         if (error)
1175                 goto fail;
1176
1177         gfs2_create_debugfs_file(sdp);
1178
1179         error = gfs2_sys_fs_add(sdp);
1180         if (error)
1181                 goto fail;
1182
1183         error = gfs2_lm_mount(sdp, silent);
1184         if (error)
1185                 goto fail_sys;
1186
1187         error = init_locking(sdp, &mount_gh, DO);
1188         if (error)
1189                 goto fail_lm;
1190
1191         error = init_sb(sdp, silent);
1192         if (error)
1193                 goto fail_locking;
1194
1195         error = init_inodes(sdp, DO);
1196         if (error)
1197                 goto fail_sb;
1198
1199         error = init_per_node(sdp, DO);
1200         if (error)
1201                 goto fail_inodes;
1202
1203         error = gfs2_statfs_init(sdp);
1204         if (error) {
1205                 fs_err(sdp, "can't initialize statfs subsystem: %d\n", error);
1206                 goto fail_per_node;
1207         }
1208
1209         error = init_threads(sdp, DO);
1210         if (error)
1211                 goto fail_per_node;
1212
1213         if (!(sb->s_flags & MS_RDONLY)) {
1214                 error = gfs2_make_fs_rw(sdp);
1215                 if (error) {
1216                         fs_err(sdp, "can't make FS RW: %d\n", error);
1217                         goto fail_threads;
1218                 }
1219         }
1220
1221         gfs2_glock_dq_uninit(&mount_gh);
1222
1223         return 0;
1224
1225 fail_threads:
1226         init_threads(sdp, UNDO);
1227 fail_per_node:
1228         init_per_node(sdp, UNDO);
1229 fail_inodes:
1230         init_inodes(sdp, UNDO);
1231 fail_sb:
1232         if (sdp->sd_root_dir)
1233                 dput(sdp->sd_root_dir);
1234         if (sdp->sd_master_dir)
1235                 dput(sdp->sd_master_dir);
1236         sb->s_root = NULL;
1237 fail_locking:
1238         init_locking(sdp, &mount_gh, UNDO);
1239 fail_lm:
1240         gfs2_gl_hash_clear(sb);
1241         gfs2_lm_unmount(sdp);
1242         while (invalidate_inodes(sb))
1243                 yield();
1244 fail_sys:
1245         gfs2_sys_fs_del(sdp);
1246 fail:
1247         gfs2_delete_debugfs_file(sdp);
1248         kfree(sdp);
1249         sb->s_fs_info = NULL;
1250         return error;
1251 }
1252
1253 static int gfs2_get_sb(struct file_system_type *fs_type, int flags,
1254                        const char *dev_name, void *data, struct vfsmount *mnt)
1255 {
1256         return get_sb_bdev(fs_type, flags, dev_name, data, fill_super, mnt);
1257 }
1258
1259 static struct super_block *get_gfs2_sb(const char *dev_name)
1260 {
1261         struct super_block *sb;
1262         struct nameidata nd;
1263         int error;
1264
1265         error = path_lookup(dev_name, LOOKUP_FOLLOW, &nd);
1266         if (error) {
1267                 printk(KERN_WARNING "GFS2: path_lookup on %s returned error %d\n",
1268                        dev_name, error);
1269                 return NULL;
1270         }
1271         sb = nd.path.dentry->d_inode->i_sb;
1272         if (sb && (sb->s_type == &gfs2_fs_type))
1273                 atomic_inc(&sb->s_active);
1274         else
1275                 sb = NULL;
1276         path_put(&nd.path);
1277         return sb;
1278 }
1279
1280 static int gfs2_get_sb_meta(struct file_system_type *fs_type, int flags,
1281                             const char *dev_name, void *data, struct vfsmount *mnt)
1282 {
1283         struct super_block *sb = NULL;
1284         struct gfs2_sbd *sdp;
1285
1286         sb = get_gfs2_sb(dev_name);
1287         if (!sb) {
1288                 printk(KERN_WARNING "GFS2: gfs2 mount does not exist\n");
1289                 return -ENOENT;
1290         }
1291         sdp = sb->s_fs_info;
1292         mnt->mnt_sb = sb;
1293         mnt->mnt_root = dget(sdp->sd_master_dir);
1294         return 0;
1295 }
1296
1297 static void gfs2_kill_sb(struct super_block *sb)
1298 {
1299         struct gfs2_sbd *sdp = sb->s_fs_info;
1300
1301         if (sdp == NULL) {
1302                 kill_block_super(sb);
1303                 return;
1304         }
1305         gfs2_meta_syncfs(sdp);
1306         dput(sdp->sd_root_dir);
1307         dput(sdp->sd_master_dir);
1308         sdp->sd_root_dir = NULL;
1309         sdp->sd_master_dir = NULL;
1310
1311         /*  Unfreeze the filesystem, if we need to  */
1312         mutex_lock(&sdp->sd_freeze_lock);
1313         if (sdp->sd_freeze_count)
1314                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
1315         mutex_unlock(&sdp->sd_freeze_lock);
1316
1317         kthread_stop(sdp->sd_quotad_process);
1318         kthread_stop(sdp->sd_logd_process);
1319         kthread_stop(sdp->sd_recoverd_process);
1320
1321         if (!(sb->s_flags & MS_RDONLY)) {
1322                 int error = gfs2_make_fs_ro(sdp);
1323                 if (error)
1324                         gfs2_io_error(sdp);
1325         }
1326
1327         /* At this point, we're through modifying the disk */
1328         gfs2_jindex_free(sdp);
1329         gfs2_clear_rgrpd(sdp);
1330         iput(sdp->sd_jindex);
1331         iput(sdp->sd_inum_inode);
1332         iput(sdp->sd_statfs_inode);
1333         iput(sdp->sd_rindex);
1334         iput(sdp->sd_quota_inode);
1335
1336         gfs2_glock_put(sdp->sd_rename_gl);
1337         gfs2_glock_put(sdp->sd_trans_gl);
1338
1339         if (!sdp->sd_args.ar_spectator) {
1340                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
1341                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
1342                 gfs2_glock_dq_uninit(&sdp->sd_ir_gh);
1343                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
1344                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
1345                 iput(sdp->sd_ir_inode);
1346                 iput(sdp->sd_sc_inode);
1347                 iput(sdp->sd_qc_inode);
1348         }
1349         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
1350         kill_block_super(sb);
1351         gfs2_lm_unmount(sdp);
1352         gfs2_sys_fs_del(sdp);
1353         gfs2_delete_debugfs_file(sdp);
1354         kfree(sdp);
1355 }
1356
1357 struct file_system_type gfs2_fs_type = {
1358         .name = "gfs2",
1359         .fs_flags = FS_REQUIRES_DEV,
1360         .get_sb = gfs2_get_sb,
1361         .kill_sb = gfs2_kill_sb,
1362         .owner = THIS_MODULE,
1363 };
1364
1365 struct file_system_type gfs2meta_fs_type = {
1366         .name = "gfs2meta",
1367         .fs_flags = FS_REQUIRES_DEV,
1368         .get_sb = gfs2_get_sb_meta,
1369         .owner = THIS_MODULE,
1370 };
1371