Reduce path_lookup() abuses
[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
21 #include "gfs2.h"
22 #include "incore.h"
23 #include "bmap.h"
24 #include "glock.h"
25 #include "glops.h"
26 #include "inode.h"
27 #include "recovery.h"
28 #include "rgrp.h"
29 #include "super.h"
30 #include "sys.h"
31 #include "util.h"
32 #include "log.h"
33 #include "quota.h"
34 #include "dir.h"
35
36 #define DO 0
37 #define UNDO 1
38
39 static const u32 gfs2_old_fs_formats[] = {
40         0
41 };
42
43 static const u32 gfs2_old_multihost_formats[] = {
44         0
45 };
46
47 /**
48  * gfs2_tune_init - Fill a gfs2_tune structure with default values
49  * @gt: tune
50  *
51  */
52
53 static void gfs2_tune_init(struct gfs2_tune *gt)
54 {
55         spin_lock_init(&gt->gt_spin);
56
57         gt->gt_incore_log_blocks = 1024;
58         gt->gt_log_flush_secs = 60;
59         gt->gt_recoverd_secs = 60;
60         gt->gt_logd_secs = 1;
61         gt->gt_quota_simul_sync = 64;
62         gt->gt_quota_warn_period = 10;
63         gt->gt_quota_scale_num = 1;
64         gt->gt_quota_scale_den = 1;
65         gt->gt_quota_quantum = 60;
66         gt->gt_new_files_jdata = 0;
67         gt->gt_max_readahead = 1 << 18;
68         gt->gt_stall_secs = 600;
69         gt->gt_complain_secs = 10;
70         gt->gt_statfs_quantum = 30;
71         gt->gt_statfs_slow = 0;
72 }
73
74 static struct gfs2_sbd *init_sbd(struct super_block *sb)
75 {
76         struct gfs2_sbd *sdp;
77
78         sdp = kzalloc(sizeof(struct gfs2_sbd), GFP_KERNEL);
79         if (!sdp)
80                 return NULL;
81
82         sb->s_fs_info = sdp;
83         sdp->sd_vfs = sb;
84
85         gfs2_tune_init(&sdp->sd_tune);
86
87         mutex_init(&sdp->sd_inum_mutex);
88         spin_lock_init(&sdp->sd_statfs_spin);
89
90         spin_lock_init(&sdp->sd_rindex_spin);
91         mutex_init(&sdp->sd_rindex_mutex);
92         INIT_LIST_HEAD(&sdp->sd_rindex_list);
93         INIT_LIST_HEAD(&sdp->sd_rindex_mru_list);
94
95         INIT_LIST_HEAD(&sdp->sd_jindex_list);
96         spin_lock_init(&sdp->sd_jindex_spin);
97         mutex_init(&sdp->sd_jindex_mutex);
98
99         INIT_LIST_HEAD(&sdp->sd_quota_list);
100         mutex_init(&sdp->sd_quota_mutex);
101         init_waitqueue_head(&sdp->sd_quota_wait);
102         INIT_LIST_HEAD(&sdp->sd_trunc_list);
103         spin_lock_init(&sdp->sd_trunc_lock);
104
105         spin_lock_init(&sdp->sd_log_lock);
106
107         INIT_LIST_HEAD(&sdp->sd_log_le_buf);
108         INIT_LIST_HEAD(&sdp->sd_log_le_revoke);
109         INIT_LIST_HEAD(&sdp->sd_log_le_rg);
110         INIT_LIST_HEAD(&sdp->sd_log_le_databuf);
111         INIT_LIST_HEAD(&sdp->sd_log_le_ordered);
112
113         mutex_init(&sdp->sd_log_reserve_mutex);
114         INIT_LIST_HEAD(&sdp->sd_ail1_list);
115         INIT_LIST_HEAD(&sdp->sd_ail2_list);
116
117         init_rwsem(&sdp->sd_log_flush_lock);
118         atomic_set(&sdp->sd_log_in_flight, 0);
119         init_waitqueue_head(&sdp->sd_log_flush_wait);
120
121         INIT_LIST_HEAD(&sdp->sd_revoke_list);
122
123         mutex_init(&sdp->sd_freeze_lock);
124
125         return sdp;
126 }
127
128
129 /**
130  * gfs2_check_sb - Check superblock
131  * @sdp: the filesystem
132  * @sb: The superblock
133  * @silent: Don't print a message if the check fails
134  *
135  * Checks the version code of the FS is one that we understand how to
136  * read and that the sizes of the various on-disk structures have not
137  * changed.
138  */
139
140 static int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb_host *sb, int silent)
141 {
142         unsigned int x;
143
144         if (sb->sb_magic != GFS2_MAGIC ||
145             sb->sb_type != GFS2_METATYPE_SB) {
146                 if (!silent)
147                         printk(KERN_WARNING "GFS2: not a GFS2 filesystem\n");
148                 return -EINVAL;
149         }
150
151         /*  If format numbers match exactly, we're done.  */
152
153         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
154             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
155                 return 0;
156
157         if (sb->sb_fs_format != GFS2_FORMAT_FS) {
158                 for (x = 0; gfs2_old_fs_formats[x]; x++)
159                         if (gfs2_old_fs_formats[x] == sb->sb_fs_format)
160                                 break;
161
162                 if (!gfs2_old_fs_formats[x]) {
163                         printk(KERN_WARNING
164                                "GFS2: code version (%u, %u) is incompatible "
165                                "with ondisk format (%u, %u)\n",
166                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
167                                sb->sb_fs_format, sb->sb_multihost_format);
168                         printk(KERN_WARNING
169                                "GFS2: I don't know how to upgrade this FS\n");
170                         return -EINVAL;
171                 }
172         }
173
174         if (sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
175                 for (x = 0; gfs2_old_multihost_formats[x]; x++)
176                         if (gfs2_old_multihost_formats[x] ==
177                             sb->sb_multihost_format)
178                                 break;
179
180                 if (!gfs2_old_multihost_formats[x]) {
181                         printk(KERN_WARNING
182                                "GFS2: code version (%u, %u) is incompatible "
183                                "with ondisk format (%u, %u)\n",
184                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
185                                sb->sb_fs_format, sb->sb_multihost_format);
186                         printk(KERN_WARNING
187                                "GFS2: I don't know how to upgrade this FS\n");
188                         return -EINVAL;
189                 }
190         }
191
192         if (!sdp->sd_args.ar_upgrade) {
193                 printk(KERN_WARNING
194                        "GFS2: code version (%u, %u) is incompatible "
195                        "with ondisk format (%u, %u)\n",
196                        GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
197                        sb->sb_fs_format, sb->sb_multihost_format);
198                 printk(KERN_INFO
199                        "GFS2: Use the \"upgrade\" mount option to upgrade "
200                        "the FS\n");
201                 printk(KERN_INFO "GFS2: See the manual for more details\n");
202                 return -EINVAL;
203         }
204
205         return 0;
206 }
207
208 static void end_bio_io_page(struct bio *bio, int error)
209 {
210         struct page *page = bio->bi_private;
211
212         if (!error)
213                 SetPageUptodate(page);
214         else
215                 printk(KERN_WARNING "gfs2: error %d reading superblock\n", error);
216         unlock_page(page);
217 }
218
219 static void gfs2_sb_in(struct gfs2_sb_host *sb, const void *buf)
220 {
221         const struct gfs2_sb *str = buf;
222
223         sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
224         sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
225         sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
226         sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
227         sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
228         sb->sb_bsize = be32_to_cpu(str->sb_bsize);
229         sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
230         sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
231         sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
232         sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
233         sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
234
235         memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
236         memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
237         memcpy(sb->sb_uuid, str->sb_uuid, 16);
238 }
239
240 /**
241  * gfs2_read_super - Read the gfs2 super block from disk
242  * @sdp: The GFS2 super block
243  * @sector: The location of the super block
244  * @error: The error code to return
245  *
246  * This uses the bio functions to read the super block from disk
247  * because we want to be 100% sure that we never read cached data.
248  * A super block is read twice only during each GFS2 mount and is
249  * never written to by the filesystem. The first time its read no
250  * locks are held, and the only details which are looked at are those
251  * relating to the locking protocol. Once locking is up and working,
252  * the sb is read again under the lock to establish the location of
253  * the master directory (contains pointers to journals etc) and the
254  * root directory.
255  *
256  * Returns: 0 on success or error
257  */
258
259 static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector)
260 {
261         struct super_block *sb = sdp->sd_vfs;
262         struct gfs2_sb *p;
263         struct page *page;
264         struct bio *bio;
265
266         page = alloc_page(GFP_NOFS);
267         if (unlikely(!page))
268                 return -ENOBUFS;
269
270         ClearPageUptodate(page);
271         ClearPageDirty(page);
272         lock_page(page);
273
274         bio = bio_alloc(GFP_NOFS, 1);
275         bio->bi_sector = sector * (sb->s_blocksize >> 9);
276         bio->bi_bdev = sb->s_bdev;
277         bio_add_page(bio, page, PAGE_SIZE, 0);
278
279         bio->bi_end_io = end_bio_io_page;
280         bio->bi_private = page;
281         submit_bio(READ_SYNC | (1 << BIO_RW_META), bio);
282         wait_on_page_locked(page);
283         bio_put(bio);
284         if (!PageUptodate(page)) {
285                 __free_page(page);
286                 return -EIO;
287         }
288         p = kmap(page);
289         gfs2_sb_in(&sdp->sd_sb, p);
290         kunmap(page);
291         __free_page(page);
292         return 0;
293 }
294
295 /**
296  * gfs2_read_sb - Read super block
297  * @sdp: The GFS2 superblock
298  * @silent: Don't print message if mount fails
299  *
300  */
301
302 static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
303 {
304         u32 hash_blocks, ind_blocks, leaf_blocks;
305         u32 tmp_blocks;
306         unsigned int x;
307         int error;
308
309         error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
310         if (error) {
311                 if (!silent)
312                         fs_err(sdp, "can't read superblock\n");
313                 return error;
314         }
315
316         error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
317         if (error)
318                 return error;
319
320         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
321                                GFS2_BASIC_BLOCK_SHIFT;
322         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
323         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
324                           sizeof(struct gfs2_dinode)) / sizeof(u64);
325         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
326                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
327         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
328         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
329         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
330         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
331         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
332                                 sizeof(struct gfs2_meta_header)) /
333                                 sizeof(struct gfs2_quota_change);
334
335         /* Compute maximum reservation required to add a entry to a directory */
336
337         hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << GFS2_DIR_MAX_DEPTH),
338                              sdp->sd_jbsize);
339
340         ind_blocks = 0;
341         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
342                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
343                 ind_blocks += tmp_blocks;
344         }
345
346         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
347
348         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
349
350         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
351                                 sizeof(struct gfs2_dinode);
352         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
353         for (x = 2;; x++) {
354                 u64 space, d;
355                 u32 m;
356
357                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
358                 d = space;
359                 m = do_div(d, sdp->sd_inptrs);
360
361                 if (d != sdp->sd_heightsize[x - 1] || m)
362                         break;
363                 sdp->sd_heightsize[x] = space;
364         }
365         sdp->sd_max_height = x;
366         sdp->sd_heightsize[x] = ~0;
367         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
368
369         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
370                                  sizeof(struct gfs2_dinode);
371         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
372         for (x = 2;; x++) {
373                 u64 space, d;
374                 u32 m;
375
376                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
377                 d = space;
378                 m = do_div(d, sdp->sd_inptrs);
379
380                 if (d != sdp->sd_jheightsize[x - 1] || m)
381                         break;
382                 sdp->sd_jheightsize[x] = space;
383         }
384         sdp->sd_max_jheight = x;
385         sdp->sd_jheightsize[x] = ~0;
386         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
387
388         return 0;
389 }
390
391 static int init_names(struct gfs2_sbd *sdp, int silent)
392 {
393         char *proto, *table;
394         int error = 0;
395
396         proto = sdp->sd_args.ar_lockproto;
397         table = sdp->sd_args.ar_locktable;
398
399         /*  Try to autodetect  */
400
401         if (!proto[0] || !table[0]) {
402                 error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
403                 if (error)
404                         return error;
405
406                 error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
407                 if (error)
408                         goto out;
409
410                 if (!proto[0])
411                         proto = sdp->sd_sb.sb_lockproto;
412                 if (!table[0])
413                         table = sdp->sd_sb.sb_locktable;
414         }
415
416         if (!table[0])
417                 table = sdp->sd_vfs->s_id;
418
419         strlcpy(sdp->sd_proto_name, proto, GFS2_FSNAME_LEN);
420         strlcpy(sdp->sd_table_name, table, GFS2_FSNAME_LEN);
421
422         table = sdp->sd_table_name;
423         while ((table = strchr(table, '/')))
424                 *table = '_';
425
426 out:
427         return error;
428 }
429
430 static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
431                         int undo)
432 {
433         int error = 0;
434
435         if (undo)
436                 goto fail_trans;
437
438         error = gfs2_glock_nq_num(sdp,
439                                   GFS2_MOUNT_LOCK, &gfs2_nondisk_glops,
440                                   LM_ST_EXCLUSIVE, LM_FLAG_NOEXP | GL_NOCACHE,
441                                   mount_gh);
442         if (error) {
443                 fs_err(sdp, "can't acquire mount glock: %d\n", error);
444                 goto fail;
445         }
446
447         error = gfs2_glock_nq_num(sdp,
448                                   GFS2_LIVE_LOCK, &gfs2_nondisk_glops,
449                                   LM_ST_SHARED,
450                                   LM_FLAG_NOEXP | GL_EXACT,
451                                   &sdp->sd_live_gh);
452         if (error) {
453                 fs_err(sdp, "can't acquire live glock: %d\n", error);
454                 goto fail_mount;
455         }
456
457         error = gfs2_glock_get(sdp, GFS2_RENAME_LOCK, &gfs2_nondisk_glops,
458                                CREATE, &sdp->sd_rename_gl);
459         if (error) {
460                 fs_err(sdp, "can't create rename glock: %d\n", error);
461                 goto fail_live;
462         }
463
464         error = gfs2_glock_get(sdp, GFS2_TRANS_LOCK, &gfs2_trans_glops,
465                                CREATE, &sdp->sd_trans_gl);
466         if (error) {
467                 fs_err(sdp, "can't create transaction glock: %d\n", error);
468                 goto fail_rename;
469         }
470
471         return 0;
472
473 fail_trans:
474         gfs2_glock_put(sdp->sd_trans_gl);
475 fail_rename:
476         gfs2_glock_put(sdp->sd_rename_gl);
477 fail_live:
478         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
479 fail_mount:
480         gfs2_glock_dq_uninit(mount_gh);
481 fail:
482         return error;
483 }
484
485 static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
486                             u64 no_addr, const char *name)
487 {
488         struct gfs2_sbd *sdp = sb->s_fs_info;
489         struct dentry *dentry;
490         struct inode *inode;
491
492         inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0, 0);
493         if (IS_ERR(inode)) {
494                 fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
495                 return PTR_ERR(inode);
496         }
497         dentry = d_alloc_root(inode);
498         if (!dentry) {
499                 fs_err(sdp, "can't alloc %s dentry\n", name);
500                 iput(inode);
501                 return -ENOMEM;
502         }
503         dentry->d_op = &gfs2_dops;
504         *dptr = dentry;
505         return 0;
506 }
507
508 static int init_sb(struct gfs2_sbd *sdp, int silent)
509 {
510         struct super_block *sb = sdp->sd_vfs;
511         struct gfs2_holder sb_gh;
512         u64 no_addr;
513         int ret;
514
515         ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
516                                 LM_ST_SHARED, 0, &sb_gh);
517         if (ret) {
518                 fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
519                 return ret;
520         }
521
522         ret = gfs2_read_sb(sdp, silent);
523         if (ret) {
524                 fs_err(sdp, "can't read superblock: %d\n", ret);
525                 goto out;
526         }
527
528         /* Set up the buffer cache and SB for real */
529         if (sdp->sd_sb.sb_bsize < bdev_hardsect_size(sb->s_bdev)) {
530                 ret = -EINVAL;
531                 fs_err(sdp, "FS block size (%u) is too small for device "
532                        "block size (%u)\n",
533                        sdp->sd_sb.sb_bsize, bdev_hardsect_size(sb->s_bdev));
534                 goto out;
535         }
536         if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
537                 ret = -EINVAL;
538                 fs_err(sdp, "FS block size (%u) is too big for machine "
539                        "page size (%u)\n",
540                        sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
541                 goto out;
542         }
543         sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
544
545         /* Get the root inode */
546         no_addr = sdp->sd_sb.sb_root_dir.no_addr;
547         ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
548         if (ret)
549                 goto out;
550
551         /* Get the master inode */
552         no_addr = sdp->sd_sb.sb_master_dir.no_addr;
553         ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
554         if (ret) {
555                 dput(sdp->sd_root_dir);
556                 goto out;
557         }
558         sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
559 out:
560         gfs2_glock_dq_uninit(&sb_gh);
561         return ret;
562 }
563
564 /**
565  * map_journal_extents - create a reusable "extent" mapping from all logical
566  * blocks to all physical blocks for the given journal.  This will save
567  * us time when writing journal blocks.  Most journals will have only one
568  * extent that maps all their logical blocks.  That's because gfs2.mkfs
569  * arranges the journal blocks sequentially to maximize performance.
570  * So the extent would map the first block for the entire file length.
571  * However, gfs2_jadd can happen while file activity is happening, so
572  * those journals may not be sequential.  Less likely is the case where
573  * the users created their own journals by mounting the metafs and
574  * laying it out.  But it's still possible.  These journals might have
575  * several extents.
576  *
577  * TODO: This should be done in bigger chunks rather than one block at a time,
578  *       but since it's only done at mount time, I'm not worried about the
579  *       time it takes.
580  */
581 static int map_journal_extents(struct gfs2_sbd *sdp)
582 {
583         struct gfs2_jdesc *jd = sdp->sd_jdesc;
584         unsigned int lb;
585         u64 db, prev_db; /* logical block, disk block, prev disk block */
586         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
587         struct gfs2_journal_extent *jext = NULL;
588         struct buffer_head bh;
589         int rc = 0;
590
591         prev_db = 0;
592
593         for (lb = 0; lb < ip->i_disksize >> sdp->sd_sb.sb_bsize_shift; lb++) {
594                 bh.b_state = 0;
595                 bh.b_blocknr = 0;
596                 bh.b_size = 1 << ip->i_inode.i_blkbits;
597                 rc = gfs2_block_map(jd->jd_inode, lb, &bh, 0);
598                 db = bh.b_blocknr;
599                 if (rc || !db) {
600                         printk(KERN_INFO "GFS2 journal mapping error %d: lb="
601                                "%u db=%llu\n", rc, lb, (unsigned long long)db);
602                         break;
603                 }
604                 if (!prev_db || db != prev_db + 1) {
605                         jext = kzalloc(sizeof(struct gfs2_journal_extent),
606                                        GFP_KERNEL);
607                         if (!jext) {
608                                 printk(KERN_INFO "GFS2 error: out of memory "
609                                        "mapping journal extents.\n");
610                                 rc = -ENOMEM;
611                                 break;
612                         }
613                         jext->dblock = db;
614                         jext->lblock = lb;
615                         jext->blocks = 1;
616                         list_add_tail(&jext->extent_list, &jd->extent_list);
617                 } else {
618                         jext->blocks++;
619                 }
620                 prev_db = db;
621         }
622         return rc;
623 }
624
625 static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
626 {
627         char *message = "FIRSTMOUNT=Done";
628         char *envp[] = { message, NULL };
629         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
630         ls->ls_first_done = 1;
631         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
632 }
633
634 /**
635  * gfs2_jindex_hold - Grab a lock on the jindex
636  * @sdp: The GFS2 superblock
637  * @ji_gh: the holder for the jindex glock
638  *
639  * Returns: errno
640  */
641
642 static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
643 {
644         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
645         struct qstr name;
646         char buf[20];
647         struct gfs2_jdesc *jd;
648         int error;
649
650         name.name = buf;
651
652         mutex_lock(&sdp->sd_jindex_mutex);
653
654         for (;;) {
655                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
656                 if (error)
657                         break;
658
659                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
660                 name.hash = gfs2_disk_hash(name.name, name.len);
661
662                 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
663                 if (error == -ENOENT) {
664                         error = 0;
665                         break;
666                 }
667
668                 gfs2_glock_dq_uninit(ji_gh);
669
670                 if (error)
671                         break;
672
673                 error = -ENOMEM;
674                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
675                 if (!jd)
676                         break;
677
678                 INIT_LIST_HEAD(&jd->extent_list);
679                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
680                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
681                         if (!jd->jd_inode)
682                                 error = -ENOENT;
683                         else
684                                 error = PTR_ERR(jd->jd_inode);
685                         kfree(jd);
686                         break;
687                 }
688
689                 spin_lock(&sdp->sd_jindex_spin);
690                 jd->jd_jid = sdp->sd_journals++;
691                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
692                 spin_unlock(&sdp->sd_jindex_spin);
693         }
694
695         mutex_unlock(&sdp->sd_jindex_mutex);
696
697         return error;
698 }
699
700 static int init_journal(struct gfs2_sbd *sdp, int undo)
701 {
702         struct inode *master = sdp->sd_master_dir->d_inode;
703         struct gfs2_holder ji_gh;
704         struct task_struct *p;
705         struct gfs2_inode *ip;
706         int jindex = 1;
707         int error = 0;
708
709         if (undo) {
710                 jindex = 0;
711                 goto fail_recoverd;
712         }
713
714         sdp->sd_jindex = gfs2_lookup_simple(master, "jindex");
715         if (IS_ERR(sdp->sd_jindex)) {
716                 fs_err(sdp, "can't lookup journal index: %d\n", error);
717                 return PTR_ERR(sdp->sd_jindex);
718         }
719         ip = GFS2_I(sdp->sd_jindex);
720
721         /* Load in the journal index special file */
722
723         error = gfs2_jindex_hold(sdp, &ji_gh);
724         if (error) {
725                 fs_err(sdp, "can't read journal index: %d\n", error);
726                 goto fail;
727         }
728
729         error = -EINVAL;
730         if (!gfs2_jindex_size(sdp)) {
731                 fs_err(sdp, "no journals!\n");
732                 goto fail_jindex;
733         }
734
735         if (sdp->sd_args.ar_spectator) {
736                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
737                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
738         } else {
739                 if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
740                         fs_err(sdp, "can't mount journal #%u\n",
741                                sdp->sd_lockstruct.ls_jid);
742                         fs_err(sdp, "there are only %u journals (0 - %u)\n",
743                                gfs2_jindex_size(sdp),
744                                gfs2_jindex_size(sdp) - 1);
745                         goto fail_jindex;
746                 }
747                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);
748
749                 error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
750                                           &gfs2_journal_glops,
751                                           LM_ST_EXCLUSIVE, LM_FLAG_NOEXP,
752                                           &sdp->sd_journal_gh);
753                 if (error) {
754                         fs_err(sdp, "can't acquire journal glock: %d\n", error);
755                         goto fail_jindex;
756                 }
757
758                 ip = GFS2_I(sdp->sd_jdesc->jd_inode);
759                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
760                                            LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE,
761                                            &sdp->sd_jinode_gh);
762                 if (error) {
763                         fs_err(sdp, "can't acquire journal inode glock: %d\n",
764                                error);
765                         goto fail_journal_gh;
766                 }
767
768                 error = gfs2_jdesc_check(sdp->sd_jdesc);
769                 if (error) {
770                         fs_err(sdp, "my journal (%u) is bad: %d\n",
771                                sdp->sd_jdesc->jd_jid, error);
772                         goto fail_jinode_gh;
773                 }
774                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
775
776                 /* Map the extents for this journal's blocks */
777                 map_journal_extents(sdp);
778         }
779
780         if (sdp->sd_lockstruct.ls_first) {
781                 unsigned int x;
782                 for (x = 0; x < sdp->sd_journals; x++) {
783                         error = gfs2_recover_journal(gfs2_jdesc_find(sdp, x));
784                         if (error) {
785                                 fs_err(sdp, "error recovering journal %u: %d\n",
786                                        x, error);
787                                 goto fail_jinode_gh;
788                         }
789                 }
790
791                 gfs2_others_may_mount(sdp);
792         } else if (!sdp->sd_args.ar_spectator) {
793                 error = gfs2_recover_journal(sdp->sd_jdesc);
794                 if (error) {
795                         fs_err(sdp, "error recovering my journal: %d\n", error);
796                         goto fail_jinode_gh;
797                 }
798         }
799
800         set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
801         gfs2_glock_dq_uninit(&ji_gh);
802         jindex = 0;
803
804         p = kthread_run(gfs2_recoverd, sdp, "gfs2_recoverd");
805         error = IS_ERR(p);
806         if (error) {
807                 fs_err(sdp, "can't start recoverd thread: %d\n", error);
808                 goto fail_jinode_gh;
809         }
810         sdp->sd_recoverd_process = p;
811
812         return 0;
813
814 fail_recoverd:
815         kthread_stop(sdp->sd_recoverd_process);
816 fail_jinode_gh:
817         if (!sdp->sd_args.ar_spectator)
818                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
819 fail_journal_gh:
820         if (!sdp->sd_args.ar_spectator)
821                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
822 fail_jindex:
823         gfs2_jindex_free(sdp);
824         if (jindex)
825                 gfs2_glock_dq_uninit(&ji_gh);
826 fail:
827         iput(sdp->sd_jindex);
828         return error;
829 }
830
831
832 static int init_inodes(struct gfs2_sbd *sdp, int undo)
833 {
834         int error = 0;
835         struct gfs2_inode *ip;
836         struct inode *master = sdp->sd_master_dir->d_inode;
837
838         if (undo)
839                 goto fail_qinode;
840
841         error = init_journal(sdp, undo);
842         if (error)
843                 goto fail;
844
845         /* Read in the master inode number inode */
846         sdp->sd_inum_inode = gfs2_lookup_simple(master, "inum");
847         if (IS_ERR(sdp->sd_inum_inode)) {
848                 error = PTR_ERR(sdp->sd_inum_inode);
849                 fs_err(sdp, "can't read in inum inode: %d\n", error);
850                 goto fail_journal;
851         }
852
853
854         /* Read in the master statfs inode */
855         sdp->sd_statfs_inode = gfs2_lookup_simple(master, "statfs");
856         if (IS_ERR(sdp->sd_statfs_inode)) {
857                 error = PTR_ERR(sdp->sd_statfs_inode);
858                 fs_err(sdp, "can't read in statfs inode: %d\n", error);
859                 goto fail_inum;
860         }
861
862         /* Read in the resource index inode */
863         sdp->sd_rindex = gfs2_lookup_simple(master, "rindex");
864         if (IS_ERR(sdp->sd_rindex)) {
865                 error = PTR_ERR(sdp->sd_rindex);
866                 fs_err(sdp, "can't get resource index inode: %d\n", error);
867                 goto fail_statfs;
868         }
869         ip = GFS2_I(sdp->sd_rindex);
870         sdp->sd_rindex_uptodate = 0;
871
872         /* Read in the quota inode */
873         sdp->sd_quota_inode = gfs2_lookup_simple(master, "quota");
874         if (IS_ERR(sdp->sd_quota_inode)) {
875                 error = PTR_ERR(sdp->sd_quota_inode);
876                 fs_err(sdp, "can't get quota file inode: %d\n", error);
877                 goto fail_rindex;
878         }
879         return 0;
880
881 fail_qinode:
882         iput(sdp->sd_quota_inode);
883 fail_rindex:
884         gfs2_clear_rgrpd(sdp);
885         iput(sdp->sd_rindex);
886 fail_statfs:
887         iput(sdp->sd_statfs_inode);
888 fail_inum:
889         iput(sdp->sd_inum_inode);
890 fail_journal:
891         init_journal(sdp, UNDO);
892 fail:
893         return error;
894 }
895
896 static int init_per_node(struct gfs2_sbd *sdp, int undo)
897 {
898         struct inode *pn = NULL;
899         char buf[30];
900         int error = 0;
901         struct gfs2_inode *ip;
902         struct inode *master = sdp->sd_master_dir->d_inode;
903
904         if (sdp->sd_args.ar_spectator)
905                 return 0;
906
907         if (undo)
908                 goto fail_qc_gh;
909
910         pn = gfs2_lookup_simple(master, "per_node");
911         if (IS_ERR(pn)) {
912                 error = PTR_ERR(pn);
913                 fs_err(sdp, "can't find per_node directory: %d\n", error);
914                 return error;
915         }
916
917         sprintf(buf, "inum_range%u", sdp->sd_jdesc->jd_jid);
918         sdp->sd_ir_inode = gfs2_lookup_simple(pn, buf);
919         if (IS_ERR(sdp->sd_ir_inode)) {
920                 error = PTR_ERR(sdp->sd_ir_inode);
921                 fs_err(sdp, "can't find local \"ir\" file: %d\n", error);
922                 goto fail;
923         }
924
925         sprintf(buf, "statfs_change%u", sdp->sd_jdesc->jd_jid);
926         sdp->sd_sc_inode = gfs2_lookup_simple(pn, buf);
927         if (IS_ERR(sdp->sd_sc_inode)) {
928                 error = PTR_ERR(sdp->sd_sc_inode);
929                 fs_err(sdp, "can't find local \"sc\" file: %d\n", error);
930                 goto fail_ir_i;
931         }
932
933         sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
934         sdp->sd_qc_inode = gfs2_lookup_simple(pn, buf);
935         if (IS_ERR(sdp->sd_qc_inode)) {
936                 error = PTR_ERR(sdp->sd_qc_inode);
937                 fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
938                 goto fail_ut_i;
939         }
940
941         iput(pn);
942         pn = NULL;
943
944         ip = GFS2_I(sdp->sd_ir_inode);
945         error = gfs2_glock_nq_init(ip->i_gl,
946                                    LM_ST_EXCLUSIVE, 0,
947                                    &sdp->sd_ir_gh);
948         if (error) {
949                 fs_err(sdp, "can't lock local \"ir\" file: %d\n", error);
950                 goto fail_qc_i;
951         }
952
953         ip = GFS2_I(sdp->sd_sc_inode);
954         error = gfs2_glock_nq_init(ip->i_gl,
955                                    LM_ST_EXCLUSIVE, 0,
956                                    &sdp->sd_sc_gh);
957         if (error) {
958                 fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
959                 goto fail_ir_gh;
960         }
961
962         ip = GFS2_I(sdp->sd_qc_inode);
963         error = gfs2_glock_nq_init(ip->i_gl,
964                                    LM_ST_EXCLUSIVE, 0,
965                                    &sdp->sd_qc_gh);
966         if (error) {
967                 fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
968                 goto fail_ut_gh;
969         }
970
971         return 0;
972
973 fail_qc_gh:
974         gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
975 fail_ut_gh:
976         gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
977 fail_ir_gh:
978         gfs2_glock_dq_uninit(&sdp->sd_ir_gh);
979 fail_qc_i:
980         iput(sdp->sd_qc_inode);
981 fail_ut_i:
982         iput(sdp->sd_sc_inode);
983 fail_ir_i:
984         iput(sdp->sd_ir_inode);
985 fail:
986         if (pn)
987                 iput(pn);
988         return error;
989 }
990
991 static int init_threads(struct gfs2_sbd *sdp, int undo)
992 {
993         struct task_struct *p;
994         int error = 0;
995
996         if (undo)
997                 goto fail_quotad;
998
999         sdp->sd_log_flush_time = jiffies;
1000
1001         p = kthread_run(gfs2_logd, sdp, "gfs2_logd");
1002         error = IS_ERR(p);
1003         if (error) {
1004                 fs_err(sdp, "can't start logd thread: %d\n", error);
1005                 return error;
1006         }
1007         sdp->sd_logd_process = p;
1008
1009         p = kthread_run(gfs2_quotad, sdp, "gfs2_quotad");
1010         error = IS_ERR(p);
1011         if (error) {
1012                 fs_err(sdp, "can't start quotad thread: %d\n", error);
1013                 goto fail;
1014         }
1015         sdp->sd_quotad_process = p;
1016
1017         return 0;
1018
1019
1020 fail_quotad:
1021         kthread_stop(sdp->sd_quotad_process);
1022 fail:
1023         kthread_stop(sdp->sd_logd_process);
1024         return error;
1025 }
1026
1027 static const match_table_t nolock_tokens = {
1028         { Opt_jid, "jid=%d\n", },
1029         { Opt_err, NULL },
1030 };
1031
1032 static const struct lm_lockops nolock_ops = {
1033         .lm_proto_name = "lock_nolock",
1034         .lm_put_lock = kmem_cache_free,
1035         .lm_tokens = &nolock_tokens,
1036 };
1037
1038 /**
1039  * gfs2_lm_mount - mount a locking protocol
1040  * @sdp: the filesystem
1041  * @args: mount arguements
1042  * @silent: if 1, don't complain if the FS isn't a GFS2 fs
1043  *
1044  * Returns: errno
1045  */
1046
1047 static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
1048 {
1049         const struct lm_lockops *lm;
1050         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
1051         struct gfs2_args *args = &sdp->sd_args;
1052         const char *proto = sdp->sd_proto_name;
1053         const char *table = sdp->sd_table_name;
1054         const char *fsname;
1055         char *o, *options;
1056         int ret;
1057
1058         if (!strcmp("lock_nolock", proto)) {
1059                 lm = &nolock_ops;
1060                 sdp->sd_args.ar_localflocks = 1;
1061                 sdp->sd_args.ar_localcaching = 1;
1062 #ifdef CONFIG_GFS2_FS_LOCKING_DLM
1063         } else if (!strcmp("lock_dlm", proto)) {
1064                 lm = &gfs2_dlm_ops;
1065 #endif
1066         } else {
1067                 printk(KERN_INFO "GFS2: can't find protocol %s\n", proto);
1068                 return -ENOENT;
1069         }
1070
1071         fs_info(sdp, "Trying to join cluster \"%s\", \"%s\"\n", proto, table);
1072
1073         ls->ls_ops = lm;
1074         ls->ls_first = 1;
1075         ls->ls_id = 0;
1076
1077         for (options = args->ar_hostdata; (o = strsep(&options, ":")); ) {
1078                 substring_t tmp[MAX_OPT_ARGS];
1079                 int token, option;
1080
1081                 if (!o || !*o)
1082                         continue;
1083
1084                 token = match_token(o, *lm->lm_tokens, tmp);
1085                 switch (token) {
1086                 case Opt_jid:
1087                         ret = match_int(&tmp[0], &option);
1088                         if (ret || option < 0) 
1089                                 goto hostdata_error;
1090                         ls->ls_jid = option;
1091                         break;
1092                 case Opt_id:
1093                         ret = match_int(&tmp[0], &option);
1094                         if (ret)
1095                                 goto hostdata_error;
1096                         ls->ls_id = option;
1097                         break;
1098                 case Opt_first:
1099                         ret = match_int(&tmp[0], &option);
1100                         if (ret || (option != 0 && option != 1))
1101                                 goto hostdata_error;
1102                         ls->ls_first = option;
1103                         break;
1104                 case Opt_nodir:
1105                         ret = match_int(&tmp[0], &option);
1106                         if (ret || (option != 0 && option != 1))
1107                                 goto hostdata_error;
1108                         ls->ls_nodir = option;
1109                         break;
1110                 case Opt_err:
1111                 default:
1112 hostdata_error:
1113                         fs_info(sdp, "unknown hostdata (%s)\n", o);
1114                         return -EINVAL;
1115                 }
1116         }
1117
1118         if (sdp->sd_args.ar_spectator)
1119                 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.s", table);
1120         else
1121                 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.%u", table,
1122                          sdp->sd_lockstruct.ls_jid);
1123
1124         fsname = strchr(table, ':');
1125         if (fsname)
1126                 fsname++;
1127         if (lm->lm_mount == NULL) {
1128                 fs_info(sdp, "Now mounting FS...\n");
1129                 return 0;
1130         }
1131         ret = lm->lm_mount(sdp, fsname);
1132         if (ret == 0)
1133                 fs_info(sdp, "Joined cluster. Now mounting FS...\n");
1134         return ret;
1135 }
1136
1137 void gfs2_lm_unmount(struct gfs2_sbd *sdp)
1138 {
1139         const struct lm_lockops *lm = sdp->sd_lockstruct.ls_ops;
1140         if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) &&
1141             lm->lm_unmount)
1142                 lm->lm_unmount(sdp);
1143 }
1144
1145 /**
1146  * fill_super - Read in superblock
1147  * @sb: The VFS superblock
1148  * @data: Mount options
1149  * @silent: Don't complain if it's not a GFS2 filesystem
1150  *
1151  * Returns: errno
1152  */
1153
1154 static int fill_super(struct super_block *sb, void *data, int silent)
1155 {
1156         struct gfs2_sbd *sdp;
1157         struct gfs2_holder mount_gh;
1158         int error;
1159
1160         sdp = init_sbd(sb);
1161         if (!sdp) {
1162                 printk(KERN_WARNING "GFS2: can't alloc struct gfs2_sbd\n");
1163                 return -ENOMEM;
1164         }
1165
1166         sdp->sd_args.ar_quota = GFS2_QUOTA_DEFAULT;
1167         sdp->sd_args.ar_data = GFS2_DATA_DEFAULT;
1168
1169         error = gfs2_mount_args(sdp, &sdp->sd_args, data);
1170         if (error) {
1171                 printk(KERN_WARNING "GFS2: can't parse mount arguments\n");
1172                 goto fail;
1173         }
1174
1175         if (sdp->sd_args.ar_spectator)
1176                 sb->s_flags |= MS_RDONLY;
1177         if (sdp->sd_args.ar_posix_acl)
1178                 sb->s_flags |= MS_POSIXACL;
1179
1180         sb->s_magic = GFS2_MAGIC;
1181         sb->s_op = &gfs2_super_ops;
1182         sb->s_export_op = &gfs2_export_ops;
1183         sb->s_time_gran = 1;
1184         sb->s_maxbytes = MAX_LFS_FILESIZE;
1185
1186         /* Set up the buffer cache and fill in some fake block size values
1187            to allow us to read-in the on-disk superblock. */
1188         sdp->sd_sb.sb_bsize = sb_min_blocksize(sb, GFS2_BASIC_BLOCK);
1189         sdp->sd_sb.sb_bsize_shift = sb->s_blocksize_bits;
1190         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
1191                                GFS2_BASIC_BLOCK_SHIFT;
1192         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
1193
1194         error = init_names(sdp, silent);
1195         if (error)
1196                 goto fail;
1197
1198         gfs2_create_debugfs_file(sdp);
1199
1200         error = gfs2_sys_fs_add(sdp);
1201         if (error)
1202                 goto fail;
1203
1204         error = gfs2_lm_mount(sdp, silent);
1205         if (error)
1206                 goto fail_sys;
1207
1208         error = init_locking(sdp, &mount_gh, DO);
1209         if (error)
1210                 goto fail_lm;
1211
1212         error = init_sb(sdp, silent);
1213         if (error)
1214                 goto fail_locking;
1215
1216         error = init_inodes(sdp, DO);
1217         if (error)
1218                 goto fail_sb;
1219
1220         error = init_per_node(sdp, DO);
1221         if (error)
1222                 goto fail_inodes;
1223
1224         error = gfs2_statfs_init(sdp);
1225         if (error) {
1226                 fs_err(sdp, "can't initialize statfs subsystem: %d\n", error);
1227                 goto fail_per_node;
1228         }
1229
1230         error = init_threads(sdp, DO);
1231         if (error)
1232                 goto fail_per_node;
1233
1234         if (!(sb->s_flags & MS_RDONLY)) {
1235                 error = gfs2_make_fs_rw(sdp);
1236                 if (error) {
1237                         fs_err(sdp, "can't make FS RW: %d\n", error);
1238                         goto fail_threads;
1239                 }
1240         }
1241
1242         gfs2_glock_dq_uninit(&mount_gh);
1243
1244         return 0;
1245
1246 fail_threads:
1247         init_threads(sdp, UNDO);
1248 fail_per_node:
1249         init_per_node(sdp, UNDO);
1250 fail_inodes:
1251         init_inodes(sdp, UNDO);
1252 fail_sb:
1253         if (sdp->sd_root_dir)
1254                 dput(sdp->sd_root_dir);
1255         if (sdp->sd_master_dir)
1256                 dput(sdp->sd_master_dir);
1257         if (sb->s_root)
1258                 dput(sb->s_root);
1259         sb->s_root = NULL;
1260 fail_locking:
1261         init_locking(sdp, &mount_gh, UNDO);
1262 fail_lm:
1263         gfs2_gl_hash_clear(sdp);
1264         gfs2_lm_unmount(sdp);
1265         while (invalidate_inodes(sb))
1266                 yield();
1267 fail_sys:
1268         gfs2_sys_fs_del(sdp);
1269 fail:
1270         gfs2_delete_debugfs_file(sdp);
1271         kfree(sdp);
1272         sb->s_fs_info = NULL;
1273         return error;
1274 }
1275
1276 static int gfs2_get_sb(struct file_system_type *fs_type, int flags,
1277                        const char *dev_name, void *data, struct vfsmount *mnt)
1278 {
1279         return get_sb_bdev(fs_type, flags, dev_name, data, fill_super, mnt);
1280 }
1281
1282 static struct super_block *get_gfs2_sb(const char *dev_name)
1283 {
1284         struct super_block *sb;
1285         struct path path;
1286         int error;
1287
1288         error = kern_path(dev_name, LOOKUP_FOLLOW, &path);
1289         if (error) {
1290                 printk(KERN_WARNING "GFS2: path_lookup on %s returned error %d\n",
1291                        dev_name, error);
1292                 return NULL;
1293         }
1294         sb = path.dentry->d_inode->i_sb;
1295         if (sb && (sb->s_type == &gfs2_fs_type))
1296                 atomic_inc(&sb->s_active);
1297         else
1298                 sb = NULL;
1299         path_put(&path);
1300         return sb;
1301 }
1302
1303 static int gfs2_get_sb_meta(struct file_system_type *fs_type, int flags,
1304                             const char *dev_name, void *data, struct vfsmount *mnt)
1305 {
1306         struct super_block *sb = NULL;
1307         struct gfs2_sbd *sdp;
1308
1309         sb = get_gfs2_sb(dev_name);
1310         if (!sb) {
1311                 printk(KERN_WARNING "GFS2: gfs2 mount does not exist\n");
1312                 return -ENOENT;
1313         }
1314         sdp = sb->s_fs_info;
1315         mnt->mnt_sb = sb;
1316         mnt->mnt_root = dget(sdp->sd_master_dir);
1317         return 0;
1318 }
1319
1320 static void gfs2_kill_sb(struct super_block *sb)
1321 {
1322         struct gfs2_sbd *sdp = sb->s_fs_info;
1323
1324         if (sdp == NULL) {
1325                 kill_block_super(sb);
1326                 return;
1327         }
1328
1329         gfs2_meta_syncfs(sdp);
1330         dput(sdp->sd_root_dir);
1331         dput(sdp->sd_master_dir);
1332         sdp->sd_root_dir = NULL;
1333         sdp->sd_master_dir = NULL;
1334         shrink_dcache_sb(sb);
1335         kill_block_super(sb);
1336         gfs2_delete_debugfs_file(sdp);
1337         kfree(sdp);
1338 }
1339
1340 struct file_system_type gfs2_fs_type = {
1341         .name = "gfs2",
1342         .fs_flags = FS_REQUIRES_DEV,
1343         .get_sb = gfs2_get_sb,
1344         .kill_sb = gfs2_kill_sb,
1345         .owner = THIS_MODULE,
1346 };
1347
1348 struct file_system_type gfs2meta_fs_type = {
1349         .name = "gfs2meta",
1350         .fs_flags = FS_REQUIRES_DEV,
1351         .get_sb = gfs2_get_sb_meta,
1352         .owner = THIS_MODULE,
1353 };
1354