Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[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/slow-work.h>
21 #include <linux/quotaops.h>
22
23 #include "gfs2.h"
24 #include "incore.h"
25 #include "bmap.h"
26 #include "glock.h"
27 #include "glops.h"
28 #include "inode.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 #include "trace_gfs2.h"
38
39 #define DO 0
40 #define UNDO 1
41
42 static const u32 gfs2_old_fs_formats[] = {
43         0
44 };
45
46 static const u32 gfs2_old_multihost_formats[] = {
47         0
48 };
49
50 /**
51  * gfs2_tune_init - Fill a gfs2_tune structure with default values
52  * @gt: tune
53  *
54  */
55
56 static void gfs2_tune_init(struct gfs2_tune *gt)
57 {
58         spin_lock_init(&gt->gt_spin);
59
60         gt->gt_incore_log_blocks = 1024;
61         gt->gt_logd_secs = 1;
62         gt->gt_quota_simul_sync = 64;
63         gt->gt_quota_warn_period = 10;
64         gt->gt_quota_scale_num = 1;
65         gt->gt_quota_scale_den = 1;
66         gt->gt_new_files_jdata = 0;
67         gt->gt_max_readahead = 1 << 18;
68         gt->gt_complain_secs = 10;
69 }
70
71 static struct gfs2_sbd *init_sbd(struct super_block *sb)
72 {
73         struct gfs2_sbd *sdp;
74
75         sdp = kzalloc(sizeof(struct gfs2_sbd), GFP_KERNEL);
76         if (!sdp)
77                 return NULL;
78
79         sb->s_fs_info = sdp;
80         sdp->sd_vfs = sb;
81
82         gfs2_tune_init(&sdp->sd_tune);
83
84         init_waitqueue_head(&sdp->sd_glock_wait);
85         atomic_set(&sdp->sd_glock_disposal, 0);
86         spin_lock_init(&sdp->sd_statfs_spin);
87
88         spin_lock_init(&sdp->sd_rindex_spin);
89         mutex_init(&sdp->sd_rindex_mutex);
90         INIT_LIST_HEAD(&sdp->sd_rindex_list);
91         INIT_LIST_HEAD(&sdp->sd_rindex_mru_list);
92
93         INIT_LIST_HEAD(&sdp->sd_jindex_list);
94         spin_lock_init(&sdp->sd_jindex_spin);
95         mutex_init(&sdp->sd_jindex_mutex);
96
97         INIT_LIST_HEAD(&sdp->sd_quota_list);
98         mutex_init(&sdp->sd_quota_mutex);
99         init_waitqueue_head(&sdp->sd_quota_wait);
100         INIT_LIST_HEAD(&sdp->sd_trunc_list);
101         spin_lock_init(&sdp->sd_trunc_lock);
102
103         spin_lock_init(&sdp->sd_log_lock);
104
105         INIT_LIST_HEAD(&sdp->sd_log_le_buf);
106         INIT_LIST_HEAD(&sdp->sd_log_le_revoke);
107         INIT_LIST_HEAD(&sdp->sd_log_le_rg);
108         INIT_LIST_HEAD(&sdp->sd_log_le_databuf);
109         INIT_LIST_HEAD(&sdp->sd_log_le_ordered);
110
111         mutex_init(&sdp->sd_log_reserve_mutex);
112         INIT_LIST_HEAD(&sdp->sd_ail1_list);
113         INIT_LIST_HEAD(&sdp->sd_ail2_list);
114
115         init_rwsem(&sdp->sd_log_flush_lock);
116         atomic_set(&sdp->sd_log_in_flight, 0);
117         init_waitqueue_head(&sdp->sd_log_flush_wait);
118
119         INIT_LIST_HEAD(&sdp->sd_revoke_list);
120
121         mutex_init(&sdp->sd_freeze_lock);
122
123         return sdp;
124 }
125
126
127 /**
128  * gfs2_check_sb - Check superblock
129  * @sdp: the filesystem
130  * @sb: The superblock
131  * @silent: Don't print a message if the check fails
132  *
133  * Checks the version code of the FS is one that we understand how to
134  * read and that the sizes of the various on-disk structures have not
135  * changed.
136  */
137
138 static int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb_host *sb, int silent)
139 {
140         unsigned int x;
141
142         if (sb->sb_magic != GFS2_MAGIC ||
143             sb->sb_type != GFS2_METATYPE_SB) {
144                 if (!silent)
145                         printk(KERN_WARNING "GFS2: not a GFS2 filesystem\n");
146                 return -EINVAL;
147         }
148
149         /*  If format numbers match exactly, we're done.  */
150
151         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
152             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
153                 return 0;
154
155         if (sb->sb_fs_format != GFS2_FORMAT_FS) {
156                 for (x = 0; gfs2_old_fs_formats[x]; x++)
157                         if (gfs2_old_fs_formats[x] == sb->sb_fs_format)
158                                 break;
159
160                 if (!gfs2_old_fs_formats[x]) {
161                         printk(KERN_WARNING
162                                "GFS2: code version (%u, %u) is incompatible "
163                                "with ondisk format (%u, %u)\n",
164                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
165                                sb->sb_fs_format, sb->sb_multihost_format);
166                         printk(KERN_WARNING
167                                "GFS2: I don't know how to upgrade this FS\n");
168                         return -EINVAL;
169                 }
170         }
171
172         if (sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
173                 for (x = 0; gfs2_old_multihost_formats[x]; x++)
174                         if (gfs2_old_multihost_formats[x] ==
175                             sb->sb_multihost_format)
176                                 break;
177
178                 if (!gfs2_old_multihost_formats[x]) {
179                         printk(KERN_WARNING
180                                "GFS2: code version (%u, %u) is incompatible "
181                                "with ondisk format (%u, %u)\n",
182                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
183                                sb->sb_fs_format, sb->sb_multihost_format);
184                         printk(KERN_WARNING
185                                "GFS2: I don't know how to upgrade this FS\n");
186                         return -EINVAL;
187                 }
188         }
189
190         if (!sdp->sd_args.ar_upgrade) {
191                 printk(KERN_WARNING
192                        "GFS2: code version (%u, %u) is incompatible "
193                        "with ondisk format (%u, %u)\n",
194                        GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
195                        sb->sb_fs_format, sb->sb_multihost_format);
196                 printk(KERN_INFO
197                        "GFS2: Use the \"upgrade\" mount option to upgrade "
198                        "the FS\n");
199                 printk(KERN_INFO "GFS2: See the manual for more details\n");
200                 return -EINVAL;
201         }
202
203         return 0;
204 }
205
206 static void end_bio_io_page(struct bio *bio, int error)
207 {
208         struct page *page = bio->bi_private;
209
210         if (!error)
211                 SetPageUptodate(page);
212         else
213                 printk(KERN_WARNING "gfs2: error %d reading superblock\n", error);
214         unlock_page(page);
215 }
216
217 static void gfs2_sb_in(struct gfs2_sb_host *sb, const void *buf)
218 {
219         const struct gfs2_sb *str = buf;
220
221         sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
222         sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
223         sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
224         sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
225         sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
226         sb->sb_bsize = be32_to_cpu(str->sb_bsize);
227         sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
228         sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
229         sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
230         sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
231         sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
232
233         memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
234         memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
235         memcpy(sb->sb_uuid, str->sb_uuid, 16);
236 }
237
238 /**
239  * gfs2_read_super - Read the gfs2 super block from disk
240  * @sdp: The GFS2 super block
241  * @sector: The location of the super block
242  * @error: The error code to return
243  *
244  * This uses the bio functions to read the super block from disk
245  * because we want to be 100% sure that we never read cached data.
246  * A super block is read twice only during each GFS2 mount and is
247  * never written to by the filesystem. The first time its read no
248  * locks are held, and the only details which are looked at are those
249  * relating to the locking protocol. Once locking is up and working,
250  * the sb is read again under the lock to establish the location of
251  * the master directory (contains pointers to journals etc) and the
252  * root directory.
253  *
254  * Returns: 0 on success or error
255  */
256
257 static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector)
258 {
259         struct super_block *sb = sdp->sd_vfs;
260         struct gfs2_sb *p;
261         struct page *page;
262         struct bio *bio;
263
264         page = alloc_page(GFP_NOFS);
265         if (unlikely(!page))
266                 return -ENOBUFS;
267
268         ClearPageUptodate(page);
269         ClearPageDirty(page);
270         lock_page(page);
271
272         bio = bio_alloc(GFP_NOFS, 1);
273         bio->bi_sector = sector * (sb->s_blocksize >> 9);
274         bio->bi_bdev = sb->s_bdev;
275         bio_add_page(bio, page, PAGE_SIZE, 0);
276
277         bio->bi_end_io = end_bio_io_page;
278         bio->bi_private = page;
279         submit_bio(READ_SYNC | (1 << BIO_RW_META), bio);
280         wait_on_page_locked(page);
281         bio_put(bio);
282         if (!PageUptodate(page)) {
283                 __free_page(page);
284                 return -EIO;
285         }
286         p = kmap(page);
287         gfs2_sb_in(&sdp->sd_sb, p);
288         kunmap(page);
289         __free_page(page);
290         return 0;
291 }
292
293 /**
294  * gfs2_read_sb - Read super block
295  * @sdp: The GFS2 superblock
296  * @silent: Don't print message if mount fails
297  *
298  */
299
300 static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
301 {
302         u32 hash_blocks, ind_blocks, leaf_blocks;
303         u32 tmp_blocks;
304         unsigned int x;
305         int error;
306
307         error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
308         if (error) {
309                 if (!silent)
310                         fs_err(sdp, "can't read superblock\n");
311                 return error;
312         }
313
314         error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
315         if (error)
316                 return error;
317
318         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
319                                GFS2_BASIC_BLOCK_SHIFT;
320         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
321         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
322                           sizeof(struct gfs2_dinode)) / sizeof(u64);
323         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
324                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
325         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
326         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
327         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
328         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
329         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
330                                 sizeof(struct gfs2_meta_header)) /
331                                 sizeof(struct gfs2_quota_change);
332
333         /* Compute maximum reservation required to add a entry to a directory */
334
335         hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << GFS2_DIR_MAX_DEPTH),
336                              sdp->sd_jbsize);
337
338         ind_blocks = 0;
339         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
340                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
341                 ind_blocks += tmp_blocks;
342         }
343
344         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
345
346         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
347
348         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
349                                 sizeof(struct gfs2_dinode);
350         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
351         for (x = 2;; x++) {
352                 u64 space, d;
353                 u32 m;
354
355                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
356                 d = space;
357                 m = do_div(d, sdp->sd_inptrs);
358
359                 if (d != sdp->sd_heightsize[x - 1] || m)
360                         break;
361                 sdp->sd_heightsize[x] = space;
362         }
363         sdp->sd_max_height = x;
364         sdp->sd_heightsize[x] = ~0;
365         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
366
367         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
368                                  sizeof(struct gfs2_dinode);
369         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
370         for (x = 2;; x++) {
371                 u64 space, d;
372                 u32 m;
373
374                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
375                 d = space;
376                 m = do_div(d, sdp->sd_inptrs);
377
378                 if (d != sdp->sd_jheightsize[x - 1] || m)
379                         break;
380                 sdp->sd_jheightsize[x] = space;
381         }
382         sdp->sd_max_jheight = x;
383         sdp->sd_jheightsize[x] = ~0;
384         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
385
386         return 0;
387 }
388
389 static int init_names(struct gfs2_sbd *sdp, int silent)
390 {
391         char *proto, *table;
392         int error = 0;
393
394         proto = sdp->sd_args.ar_lockproto;
395         table = sdp->sd_args.ar_locktable;
396
397         /*  Try to autodetect  */
398
399         if (!proto[0] || !table[0]) {
400                 error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
401                 if (error)
402                         return error;
403
404                 error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
405                 if (error)
406                         goto out;
407
408                 if (!proto[0])
409                         proto = sdp->sd_sb.sb_lockproto;
410                 if (!table[0])
411                         table = sdp->sd_sb.sb_locktable;
412         }
413
414         if (!table[0])
415                 table = sdp->sd_vfs->s_id;
416
417         strlcpy(sdp->sd_proto_name, proto, GFS2_FSNAME_LEN);
418         strlcpy(sdp->sd_table_name, table, GFS2_FSNAME_LEN);
419
420         table = sdp->sd_table_name;
421         while ((table = strchr(table, '/')))
422                 *table = '_';
423
424 out:
425         return error;
426 }
427
428 static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
429                         int undo)
430 {
431         int error = 0;
432
433         if (undo)
434                 goto fail_trans;
435
436         error = gfs2_glock_nq_num(sdp,
437                                   GFS2_MOUNT_LOCK, &gfs2_nondisk_glops,
438                                   LM_ST_EXCLUSIVE, LM_FLAG_NOEXP | GL_NOCACHE,
439                                   mount_gh);
440         if (error) {
441                 fs_err(sdp, "can't acquire mount glock: %d\n", error);
442                 goto fail;
443         }
444
445         error = gfs2_glock_nq_num(sdp,
446                                   GFS2_LIVE_LOCK, &gfs2_nondisk_glops,
447                                   LM_ST_SHARED,
448                                   LM_FLAG_NOEXP | GL_EXACT,
449                                   &sdp->sd_live_gh);
450         if (error) {
451                 fs_err(sdp, "can't acquire live glock: %d\n", error);
452                 goto fail_mount;
453         }
454
455         error = gfs2_glock_get(sdp, GFS2_RENAME_LOCK, &gfs2_nondisk_glops,
456                                CREATE, &sdp->sd_rename_gl);
457         if (error) {
458                 fs_err(sdp, "can't create rename glock: %d\n", error);
459                 goto fail_live;
460         }
461
462         error = gfs2_glock_get(sdp, GFS2_TRANS_LOCK, &gfs2_trans_glops,
463                                CREATE, &sdp->sd_trans_gl);
464         if (error) {
465                 fs_err(sdp, "can't create transaction glock: %d\n", error);
466                 goto fail_rename;
467         }
468
469         return 0;
470
471 fail_trans:
472         gfs2_glock_put(sdp->sd_trans_gl);
473 fail_rename:
474         gfs2_glock_put(sdp->sd_rename_gl);
475 fail_live:
476         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
477 fail_mount:
478         gfs2_glock_dq_uninit(mount_gh);
479 fail:
480         return error;
481 }
482
483 static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
484                             u64 no_addr, const char *name)
485 {
486         struct gfs2_sbd *sdp = sb->s_fs_info;
487         struct dentry *dentry;
488         struct inode *inode;
489
490         inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0, 0);
491         if (IS_ERR(inode)) {
492                 fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
493                 return PTR_ERR(inode);
494         }
495         dentry = d_alloc_root(inode);
496         if (!dentry) {
497                 fs_err(sdp, "can't alloc %s dentry\n", name);
498                 iput(inode);
499                 return -ENOMEM;
500         }
501         dentry->d_op = &gfs2_dops;
502         *dptr = dentry;
503         return 0;
504 }
505
506 static int init_sb(struct gfs2_sbd *sdp, int silent)
507 {
508         struct super_block *sb = sdp->sd_vfs;
509         struct gfs2_holder sb_gh;
510         u64 no_addr;
511         int ret;
512
513         ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
514                                 LM_ST_SHARED, 0, &sb_gh);
515         if (ret) {
516                 fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
517                 return ret;
518         }
519
520         ret = gfs2_read_sb(sdp, silent);
521         if (ret) {
522                 fs_err(sdp, "can't read superblock: %d\n", ret);
523                 goto out;
524         }
525
526         /* Set up the buffer cache and SB for real */
527         if (sdp->sd_sb.sb_bsize < bdev_logical_block_size(sb->s_bdev)) {
528                 ret = -EINVAL;
529                 fs_err(sdp, "FS block size (%u) is too small for device "
530                        "block size (%u)\n",
531                        sdp->sd_sb.sb_bsize, bdev_logical_block_size(sb->s_bdev));
532                 goto out;
533         }
534         if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
535                 ret = -EINVAL;
536                 fs_err(sdp, "FS block size (%u) is too big for machine "
537                        "page size (%u)\n",
538                        sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
539                 goto out;
540         }
541         sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
542
543         /* Get the root inode */
544         no_addr = sdp->sd_sb.sb_root_dir.no_addr;
545         ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
546         if (ret)
547                 goto out;
548
549         /* Get the master inode */
550         no_addr = sdp->sd_sb.sb_master_dir.no_addr;
551         ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
552         if (ret) {
553                 dput(sdp->sd_root_dir);
554                 goto out;
555         }
556         sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
557 out:
558         gfs2_glock_dq_uninit(&sb_gh);
559         return ret;
560 }
561
562 /**
563  * map_journal_extents - create a reusable "extent" mapping from all logical
564  * blocks to all physical blocks for the given journal.  This will save
565  * us time when writing journal blocks.  Most journals will have only one
566  * extent that maps all their logical blocks.  That's because gfs2.mkfs
567  * arranges the journal blocks sequentially to maximize performance.
568  * So the extent would map the first block for the entire file length.
569  * However, gfs2_jadd can happen while file activity is happening, so
570  * those journals may not be sequential.  Less likely is the case where
571  * the users created their own journals by mounting the metafs and
572  * laying it out.  But it's still possible.  These journals might have
573  * several extents.
574  *
575  * TODO: This should be done in bigger chunks rather than one block at a time,
576  *       but since it's only done at mount time, I'm not worried about the
577  *       time it takes.
578  */
579 static int map_journal_extents(struct gfs2_sbd *sdp)
580 {
581         struct gfs2_jdesc *jd = sdp->sd_jdesc;
582         unsigned int lb;
583         u64 db, prev_db; /* logical block, disk block, prev disk block */
584         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
585         struct gfs2_journal_extent *jext = NULL;
586         struct buffer_head bh;
587         int rc = 0;
588
589         prev_db = 0;
590
591         for (lb = 0; lb < ip->i_disksize >> sdp->sd_sb.sb_bsize_shift; lb++) {
592                 bh.b_state = 0;
593                 bh.b_blocknr = 0;
594                 bh.b_size = 1 << ip->i_inode.i_blkbits;
595                 rc = gfs2_block_map(jd->jd_inode, lb, &bh, 0);
596                 db = bh.b_blocknr;
597                 if (rc || !db) {
598                         printk(KERN_INFO "GFS2 journal mapping error %d: lb="
599                                "%u db=%llu\n", rc, lb, (unsigned long long)db);
600                         break;
601                 }
602                 if (!prev_db || db != prev_db + 1) {
603                         jext = kzalloc(sizeof(struct gfs2_journal_extent),
604                                        GFP_KERNEL);
605                         if (!jext) {
606                                 printk(KERN_INFO "GFS2 error: out of memory "
607                                        "mapping journal extents.\n");
608                                 rc = -ENOMEM;
609                                 break;
610                         }
611                         jext->dblock = db;
612                         jext->lblock = lb;
613                         jext->blocks = 1;
614                         list_add_tail(&jext->extent_list, &jd->extent_list);
615                 } else {
616                         jext->blocks++;
617                 }
618                 prev_db = db;
619         }
620         return rc;
621 }
622
623 static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
624 {
625         char *message = "FIRSTMOUNT=Done";
626         char *envp[] = { message, NULL };
627         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
628         ls->ls_first_done = 1;
629         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
630 }
631
632 /**
633  * gfs2_jindex_hold - Grab a lock on the jindex
634  * @sdp: The GFS2 superblock
635  * @ji_gh: the holder for the jindex glock
636  *
637  * Returns: errno
638  */
639
640 static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
641 {
642         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
643         struct qstr name;
644         char buf[20];
645         struct gfs2_jdesc *jd;
646         int error;
647
648         name.name = buf;
649
650         mutex_lock(&sdp->sd_jindex_mutex);
651
652         for (;;) {
653                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
654                 if (error)
655                         break;
656
657                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
658                 name.hash = gfs2_disk_hash(name.name, name.len);
659
660                 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
661                 if (error == -ENOENT) {
662                         error = 0;
663                         break;
664                 }
665
666                 gfs2_glock_dq_uninit(ji_gh);
667
668                 if (error)
669                         break;
670
671                 error = -ENOMEM;
672                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
673                 if (!jd)
674                         break;
675
676                 INIT_LIST_HEAD(&jd->extent_list);
677                 slow_work_init(&jd->jd_work, &gfs2_recover_ops);
678                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
679                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
680                         if (!jd->jd_inode)
681                                 error = -ENOENT;
682                         else
683                                 error = PTR_ERR(jd->jd_inode);
684                         kfree(jd);
685                         break;
686                 }
687
688                 spin_lock(&sdp->sd_jindex_spin);
689                 jd->jd_jid = sdp->sd_journals++;
690                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
691                 spin_unlock(&sdp->sd_jindex_spin);
692         }
693
694         mutex_unlock(&sdp->sd_jindex_mutex);
695
696         return error;
697 }
698
699 static int init_journal(struct gfs2_sbd *sdp, int undo)
700 {
701         struct inode *master = sdp->sd_master_dir->d_inode;
702         struct gfs2_holder ji_gh;
703         struct gfs2_inode *ip;
704         int jindex = 1;
705         int error = 0;
706
707         if (undo) {
708                 jindex = 0;
709                 goto fail_jinode_gh;
710         }
711
712         sdp->sd_jindex = gfs2_lookup_simple(master, "jindex");
713         if (IS_ERR(sdp->sd_jindex)) {
714                 fs_err(sdp, "can't lookup journal index: %d\n", error);
715                 return PTR_ERR(sdp->sd_jindex);
716         }
717         ip = GFS2_I(sdp->sd_jindex);
718
719         /* Load in the journal index special file */
720
721         error = gfs2_jindex_hold(sdp, &ji_gh);
722         if (error) {
723                 fs_err(sdp, "can't read journal index: %d\n", error);
724                 goto fail;
725         }
726
727         error = -EUSERS;
728         if (!gfs2_jindex_size(sdp)) {
729                 fs_err(sdp, "no journals!\n");
730                 goto fail_jindex;
731         }
732
733         if (sdp->sd_args.ar_spectator) {
734                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
735                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
736         } else {
737                 if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
738                         fs_err(sdp, "can't mount journal #%u\n",
739                                sdp->sd_lockstruct.ls_jid);
740                         fs_err(sdp, "there are only %u journals (0 - %u)\n",
741                                gfs2_jindex_size(sdp),
742                                gfs2_jindex_size(sdp) - 1);
743                         goto fail_jindex;
744                 }
745                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);
746
747                 error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
748                                           &gfs2_journal_glops,
749                                           LM_ST_EXCLUSIVE, LM_FLAG_NOEXP,
750                                           &sdp->sd_journal_gh);
751                 if (error) {
752                         fs_err(sdp, "can't acquire journal glock: %d\n", error);
753                         goto fail_jindex;
754                 }
755
756                 ip = GFS2_I(sdp->sd_jdesc->jd_inode);
757                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
758                                            LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE,
759                                            &sdp->sd_jinode_gh);
760                 if (error) {
761                         fs_err(sdp, "can't acquire journal inode glock: %d\n",
762                                error);
763                         goto fail_journal_gh;
764                 }
765
766                 error = gfs2_jdesc_check(sdp->sd_jdesc);
767                 if (error) {
768                         fs_err(sdp, "my journal (%u) is bad: %d\n",
769                                sdp->sd_jdesc->jd_jid, error);
770                         goto fail_jinode_gh;
771                 }
772                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
773
774                 /* Map the extents for this journal's blocks */
775                 map_journal_extents(sdp);
776         }
777         trace_gfs2_log_blocks(sdp, atomic_read(&sdp->sd_log_blks_free));
778
779         if (sdp->sd_lockstruct.ls_first) {
780                 unsigned int x;
781                 for (x = 0; x < sdp->sd_journals; x++) {
782                         error = gfs2_recover_journal(gfs2_jdesc_find(sdp, x));
783                         if (error) {
784                                 fs_err(sdp, "error recovering journal %u: %d\n",
785                                        x, error);
786                                 goto fail_jinode_gh;
787                         }
788                 }
789
790                 gfs2_others_may_mount(sdp);
791         } else if (!sdp->sd_args.ar_spectator) {
792                 error = gfs2_recover_journal(sdp->sd_jdesc);
793                 if (error) {
794                         fs_err(sdp, "error recovering my journal: %d\n", error);
795                         goto fail_jinode_gh;
796                 }
797         }
798
799         set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
800         gfs2_glock_dq_uninit(&ji_gh);
801         jindex = 0;
802
803         return 0;
804
805 fail_jinode_gh:
806         if (!sdp->sd_args.ar_spectator)
807                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
808 fail_journal_gh:
809         if (!sdp->sd_args.ar_spectator)
810                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
811 fail_jindex:
812         gfs2_jindex_free(sdp);
813         if (jindex)
814                 gfs2_glock_dq_uninit(&ji_gh);
815 fail:
816         iput(sdp->sd_jindex);
817         return error;
818 }
819
820
821 static int init_inodes(struct gfs2_sbd *sdp, int undo)
822 {
823         int error = 0;
824         struct gfs2_inode *ip;
825         struct inode *master = sdp->sd_master_dir->d_inode;
826
827         if (undo)
828                 goto fail_qinode;
829
830         error = init_journal(sdp, undo);
831         if (error)
832                 goto fail;
833
834         /* Read in the master statfs inode */
835         sdp->sd_statfs_inode = gfs2_lookup_simple(master, "statfs");
836         if (IS_ERR(sdp->sd_statfs_inode)) {
837                 error = PTR_ERR(sdp->sd_statfs_inode);
838                 fs_err(sdp, "can't read in statfs inode: %d\n", error);
839                 goto fail_journal;
840         }
841
842         /* Read in the resource index inode */
843         sdp->sd_rindex = gfs2_lookup_simple(master, "rindex");
844         if (IS_ERR(sdp->sd_rindex)) {
845                 error = PTR_ERR(sdp->sd_rindex);
846                 fs_err(sdp, "can't get resource index inode: %d\n", error);
847                 goto fail_statfs;
848         }
849         ip = GFS2_I(sdp->sd_rindex);
850         sdp->sd_rindex_uptodate = 0;
851
852         /* Read in the quota inode */
853         sdp->sd_quota_inode = gfs2_lookup_simple(master, "quota");
854         if (IS_ERR(sdp->sd_quota_inode)) {
855                 error = PTR_ERR(sdp->sd_quota_inode);
856                 fs_err(sdp, "can't get quota file inode: %d\n", error);
857                 goto fail_rindex;
858         }
859         return 0;
860
861 fail_qinode:
862         iput(sdp->sd_quota_inode);
863 fail_rindex:
864         gfs2_clear_rgrpd(sdp);
865         iput(sdp->sd_rindex);
866 fail_statfs:
867         iput(sdp->sd_statfs_inode);
868 fail_journal:
869         init_journal(sdp, UNDO);
870 fail:
871         return error;
872 }
873
874 static int init_per_node(struct gfs2_sbd *sdp, int undo)
875 {
876         struct inode *pn = NULL;
877         char buf[30];
878         int error = 0;
879         struct gfs2_inode *ip;
880         struct inode *master = sdp->sd_master_dir->d_inode;
881
882         if (sdp->sd_args.ar_spectator)
883                 return 0;
884
885         if (undo)
886                 goto fail_qc_gh;
887
888         pn = gfs2_lookup_simple(master, "per_node");
889         if (IS_ERR(pn)) {
890                 error = PTR_ERR(pn);
891                 fs_err(sdp, "can't find per_node directory: %d\n", error);
892                 return error;
893         }
894
895         sprintf(buf, "statfs_change%u", sdp->sd_jdesc->jd_jid);
896         sdp->sd_sc_inode = gfs2_lookup_simple(pn, buf);
897         if (IS_ERR(sdp->sd_sc_inode)) {
898                 error = PTR_ERR(sdp->sd_sc_inode);
899                 fs_err(sdp, "can't find local \"sc\" file: %d\n", error);
900                 goto fail;
901         }
902
903         sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
904         sdp->sd_qc_inode = gfs2_lookup_simple(pn, buf);
905         if (IS_ERR(sdp->sd_qc_inode)) {
906                 error = PTR_ERR(sdp->sd_qc_inode);
907                 fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
908                 goto fail_ut_i;
909         }
910
911         iput(pn);
912         pn = NULL;
913
914         ip = GFS2_I(sdp->sd_sc_inode);
915         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
916                                    &sdp->sd_sc_gh);
917         if (error) {
918                 fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
919                 goto fail_qc_i;
920         }
921
922         ip = GFS2_I(sdp->sd_qc_inode);
923         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
924                                    &sdp->sd_qc_gh);
925         if (error) {
926                 fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
927                 goto fail_ut_gh;
928         }
929
930         return 0;
931
932 fail_qc_gh:
933         gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
934 fail_ut_gh:
935         gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
936 fail_qc_i:
937         iput(sdp->sd_qc_inode);
938 fail_ut_i:
939         iput(sdp->sd_sc_inode);
940 fail:
941         if (pn)
942                 iput(pn);
943         return error;
944 }
945
946 static int init_threads(struct gfs2_sbd *sdp, int undo)
947 {
948         struct task_struct *p;
949         int error = 0;
950
951         if (undo)
952                 goto fail_quotad;
953
954         sdp->sd_log_flush_time = jiffies;
955
956         p = kthread_run(gfs2_logd, sdp, "gfs2_logd");
957         error = IS_ERR(p);
958         if (error) {
959                 fs_err(sdp, "can't start logd thread: %d\n", error);
960                 return error;
961         }
962         sdp->sd_logd_process = p;
963
964         p = kthread_run(gfs2_quotad, sdp, "gfs2_quotad");
965         error = IS_ERR(p);
966         if (error) {
967                 fs_err(sdp, "can't start quotad thread: %d\n", error);
968                 goto fail;
969         }
970         sdp->sd_quotad_process = p;
971
972         return 0;
973
974
975 fail_quotad:
976         kthread_stop(sdp->sd_quotad_process);
977 fail:
978         kthread_stop(sdp->sd_logd_process);
979         return error;
980 }
981
982 static const match_table_t nolock_tokens = {
983         { Opt_jid, "jid=%d\n", },
984         { Opt_err, NULL },
985 };
986
987 static void nolock_put_lock(struct kmem_cache *cachep, struct gfs2_glock *gl)
988 {
989         struct gfs2_sbd *sdp = gl->gl_sbd;
990         kmem_cache_free(cachep, gl);
991         if (atomic_dec_and_test(&sdp->sd_glock_disposal))
992                 wake_up(&sdp->sd_glock_wait);
993 }
994
995 static const struct lm_lockops nolock_ops = {
996         .lm_proto_name = "lock_nolock",
997         .lm_put_lock = nolock_put_lock,
998         .lm_tokens = &nolock_tokens,
999 };
1000
1001 /**
1002  * gfs2_lm_mount - mount a locking protocol
1003  * @sdp: the filesystem
1004  * @args: mount arguments
1005  * @silent: if 1, don't complain if the FS isn't a GFS2 fs
1006  *
1007  * Returns: errno
1008  */
1009
1010 static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
1011 {
1012         const struct lm_lockops *lm;
1013         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
1014         struct gfs2_args *args = &sdp->sd_args;
1015         const char *proto = sdp->sd_proto_name;
1016         const char *table = sdp->sd_table_name;
1017         const char *fsname;
1018         char *o, *options;
1019         int ret;
1020
1021         if (!strcmp("lock_nolock", proto)) {
1022                 lm = &nolock_ops;
1023                 sdp->sd_args.ar_localflocks = 1;
1024                 sdp->sd_args.ar_localcaching = 1;
1025 #ifdef CONFIG_GFS2_FS_LOCKING_DLM
1026         } else if (!strcmp("lock_dlm", proto)) {
1027                 lm = &gfs2_dlm_ops;
1028 #endif
1029         } else {
1030                 printk(KERN_INFO "GFS2: can't find protocol %s\n", proto);
1031                 return -ENOENT;
1032         }
1033
1034         fs_info(sdp, "Trying to join cluster \"%s\", \"%s\"\n", proto, table);
1035
1036         ls->ls_ops = lm;
1037         ls->ls_first = 1;
1038
1039         for (options = args->ar_hostdata; (o = strsep(&options, ":")); ) {
1040                 substring_t tmp[MAX_OPT_ARGS];
1041                 int token, option;
1042
1043                 if (!o || !*o)
1044                         continue;
1045
1046                 token = match_token(o, *lm->lm_tokens, tmp);
1047                 switch (token) {
1048                 case Opt_jid:
1049                         ret = match_int(&tmp[0], &option);
1050                         if (ret || option < 0) 
1051                                 goto hostdata_error;
1052                         ls->ls_jid = option;
1053                         break;
1054                 case Opt_id:
1055                         /* Obsolete, but left for backward compat purposes */
1056                         break;
1057                 case Opt_first:
1058                         ret = match_int(&tmp[0], &option);
1059                         if (ret || (option != 0 && option != 1))
1060                                 goto hostdata_error;
1061                         ls->ls_first = option;
1062                         break;
1063                 case Opt_nodir:
1064                         ret = match_int(&tmp[0], &option);
1065                         if (ret || (option != 0 && option != 1))
1066                                 goto hostdata_error;
1067                         ls->ls_nodir = option;
1068                         break;
1069                 case Opt_err:
1070                 default:
1071 hostdata_error:
1072                         fs_info(sdp, "unknown hostdata (%s)\n", o);
1073                         return -EINVAL;
1074                 }
1075         }
1076
1077         if (sdp->sd_args.ar_spectator)
1078                 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.s", table);
1079         else
1080                 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.%u", table,
1081                          sdp->sd_lockstruct.ls_jid);
1082
1083         fsname = strchr(table, ':');
1084         if (fsname)
1085                 fsname++;
1086         if (lm->lm_mount == NULL) {
1087                 fs_info(sdp, "Now mounting FS...\n");
1088                 return 0;
1089         }
1090         ret = lm->lm_mount(sdp, fsname);
1091         if (ret == 0)
1092                 fs_info(sdp, "Joined cluster. Now mounting FS...\n");
1093         return ret;
1094 }
1095
1096 void gfs2_lm_unmount(struct gfs2_sbd *sdp)
1097 {
1098         const struct lm_lockops *lm = sdp->sd_lockstruct.ls_ops;
1099         if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) &&
1100             lm->lm_unmount)
1101                 lm->lm_unmount(sdp);
1102 }
1103
1104 void gfs2_online_uevent(struct gfs2_sbd *sdp)
1105 {
1106         struct super_block *sb = sdp->sd_vfs;
1107         char ro[20];
1108         char spectator[20];
1109         char *envp[] = { ro, spectator, NULL };
1110         sprintf(ro, "RDONLY=%d", (sb->s_flags & MS_RDONLY) ? 1 : 0);
1111         sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
1112         kobject_uevent_env(&sdp->sd_kobj, KOBJ_ONLINE, envp);
1113 }
1114
1115 /**
1116  * fill_super - Read in superblock
1117  * @sb: The VFS superblock
1118  * @data: Mount options
1119  * @silent: Don't complain if it's not a GFS2 filesystem
1120  *
1121  * Returns: errno
1122  */
1123
1124 static int fill_super(struct super_block *sb, struct gfs2_args *args, int silent)
1125 {
1126         struct gfs2_sbd *sdp;
1127         struct gfs2_holder mount_gh;
1128         int error;
1129
1130         sdp = init_sbd(sb);
1131         if (!sdp) {
1132                 printk(KERN_WARNING "GFS2: can't alloc struct gfs2_sbd\n");
1133                 return -ENOMEM;
1134         }
1135         sdp->sd_args = *args;
1136
1137         if (sdp->sd_args.ar_spectator) {
1138                 sb->s_flags |= MS_RDONLY;
1139                 set_bit(SDF_NORECOVERY, &sdp->sd_flags);
1140         }
1141         if (sdp->sd_args.ar_posix_acl)
1142                 sb->s_flags |= MS_POSIXACL;
1143         if (sdp->sd_args.ar_nobarrier)
1144                 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1145
1146         sb->s_magic = GFS2_MAGIC;
1147         sb->s_op = &gfs2_super_ops;
1148         sb->s_export_op = &gfs2_export_ops;
1149         sb->s_xattr = gfs2_xattr_handlers;
1150         sb->s_qcop = &gfs2_quotactl_ops;
1151         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
1152         sb->s_time_gran = 1;
1153         sb->s_maxbytes = MAX_LFS_FILESIZE;
1154
1155         /* Set up the buffer cache and fill in some fake block size values
1156            to allow us to read-in the on-disk superblock. */
1157         sdp->sd_sb.sb_bsize = sb_min_blocksize(sb, GFS2_BASIC_BLOCK);
1158         sdp->sd_sb.sb_bsize_shift = sb->s_blocksize_bits;
1159         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
1160                                GFS2_BASIC_BLOCK_SHIFT;
1161         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
1162
1163         sdp->sd_tune.gt_log_flush_secs = sdp->sd_args.ar_commit;
1164         sdp->sd_tune.gt_quota_quantum = sdp->sd_args.ar_quota_quantum;
1165         if (sdp->sd_args.ar_statfs_quantum) {
1166                 sdp->sd_tune.gt_statfs_slow = 0;
1167                 sdp->sd_tune.gt_statfs_quantum = sdp->sd_args.ar_statfs_quantum;
1168         }
1169         else {
1170                 sdp->sd_tune.gt_statfs_slow = 1;
1171                 sdp->sd_tune.gt_statfs_quantum = 30;
1172         }
1173
1174         error = init_names(sdp, silent);
1175         if (error)
1176                 goto fail;
1177
1178         gfs2_create_debugfs_file(sdp);
1179
1180         error = gfs2_sys_fs_add(sdp);
1181         if (error)
1182                 goto fail;
1183
1184         error = gfs2_lm_mount(sdp, silent);
1185         if (error)
1186                 goto fail_sys;
1187
1188         error = init_locking(sdp, &mount_gh, DO);
1189         if (error)
1190                 goto fail_lm;
1191
1192         error = init_sb(sdp, silent);
1193         if (error)
1194                 goto fail_locking;
1195
1196         error = init_inodes(sdp, DO);
1197         if (error)
1198                 goto fail_sb;
1199
1200         error = init_per_node(sdp, DO);
1201         if (error)
1202                 goto fail_inodes;
1203
1204         error = gfs2_statfs_init(sdp);
1205         if (error) {
1206                 fs_err(sdp, "can't initialize statfs subsystem: %d\n", error);
1207                 goto fail_per_node;
1208         }
1209
1210         error = init_threads(sdp, DO);
1211         if (error)
1212                 goto fail_per_node;
1213
1214         if (!(sb->s_flags & MS_RDONLY)) {
1215                 error = gfs2_make_fs_rw(sdp);
1216                 if (error) {
1217                         fs_err(sdp, "can't make FS RW: %d\n", error);
1218                         goto fail_threads;
1219                 }
1220         }
1221
1222         gfs2_glock_dq_uninit(&mount_gh);
1223         gfs2_online_uevent(sdp);
1224         return 0;
1225
1226 fail_threads:
1227         init_threads(sdp, UNDO);
1228 fail_per_node:
1229         init_per_node(sdp, UNDO);
1230 fail_inodes:
1231         init_inodes(sdp, UNDO);
1232 fail_sb:
1233         if (sdp->sd_root_dir)
1234                 dput(sdp->sd_root_dir);
1235         if (sdp->sd_master_dir)
1236                 dput(sdp->sd_master_dir);
1237         if (sb->s_root)
1238                 dput(sb->s_root);
1239         sb->s_root = NULL;
1240 fail_locking:
1241         init_locking(sdp, &mount_gh, UNDO);
1242 fail_lm:
1243         invalidate_inodes(sb);
1244         gfs2_gl_hash_clear(sdp);
1245         gfs2_lm_unmount(sdp);
1246 fail_sys:
1247         gfs2_sys_fs_del(sdp);
1248 fail:
1249         gfs2_delete_debugfs_file(sdp);
1250         kfree(sdp);
1251         sb->s_fs_info = NULL;
1252         return error;
1253 }
1254
1255 static int set_gfs2_super(struct super_block *s, void *data)
1256 {
1257         s->s_bdev = data;
1258         s->s_dev = s->s_bdev->bd_dev;
1259
1260         /*
1261          * We set the bdi here to the queue backing, file systems can
1262          * overwrite this in ->fill_super()
1263          */
1264         s->s_bdi = &bdev_get_queue(s->s_bdev)->backing_dev_info;
1265         return 0;
1266 }
1267
1268 static int test_gfs2_super(struct super_block *s, void *ptr)
1269 {
1270         struct block_device *bdev = ptr;
1271         return (bdev == s->s_bdev);
1272 }
1273
1274 /**
1275  * gfs2_get_sb - Get the GFS2 superblock
1276  * @fs_type: The GFS2 filesystem type
1277  * @flags: Mount flags
1278  * @dev_name: The name of the device
1279  * @data: The mount arguments
1280  * @mnt: The vfsmnt for this mount
1281  *
1282  * Q. Why not use get_sb_bdev() ?
1283  * A. We need to select one of two root directories to mount, independent
1284  *    of whether this is the initial, or subsequent, mount of this sb
1285  *
1286  * Returns: 0 or -ve on error
1287  */
1288
1289 static int gfs2_get_sb(struct file_system_type *fs_type, int flags,
1290                        const char *dev_name, void *data, struct vfsmount *mnt)
1291 {
1292         struct block_device *bdev;
1293         struct super_block *s;
1294         fmode_t mode = FMODE_READ;
1295         int error;
1296         struct gfs2_args args;
1297         struct gfs2_sbd *sdp;
1298
1299         if (!(flags & MS_RDONLY))
1300                 mode |= FMODE_WRITE;
1301
1302         bdev = open_bdev_exclusive(dev_name, mode, fs_type);
1303         if (IS_ERR(bdev))
1304                 return PTR_ERR(bdev);
1305
1306         /*
1307          * once the super is inserted into the list by sget, s_umount
1308          * will protect the lockfs code from trying to start a snapshot
1309          * while we are mounting
1310          */
1311         mutex_lock(&bdev->bd_fsfreeze_mutex);
1312         if (bdev->bd_fsfreeze_count > 0) {
1313                 mutex_unlock(&bdev->bd_fsfreeze_mutex);
1314                 error = -EBUSY;
1315                 goto error_bdev;
1316         }
1317         s = sget(fs_type, test_gfs2_super, set_gfs2_super, bdev);
1318         mutex_unlock(&bdev->bd_fsfreeze_mutex);
1319         error = PTR_ERR(s);
1320         if (IS_ERR(s))
1321                 goto error_bdev;
1322
1323         memset(&args, 0, sizeof(args));
1324         args.ar_quota = GFS2_QUOTA_DEFAULT;
1325         args.ar_data = GFS2_DATA_DEFAULT;
1326         args.ar_commit = 60;
1327         args.ar_statfs_quantum = 30;
1328         args.ar_quota_quantum = 60;
1329         args.ar_errors = GFS2_ERRORS_DEFAULT;
1330
1331         error = gfs2_mount_args(&args, data);
1332         if (error) {
1333                 printk(KERN_WARNING "GFS2: can't parse mount arguments\n");
1334                 if (s->s_root)
1335                         goto error_super;
1336                 deactivate_locked_super(s);
1337                 return error;
1338         }
1339
1340         if (s->s_root) {
1341                 error = -EBUSY;
1342                 if ((flags ^ s->s_flags) & MS_RDONLY)
1343                         goto error_super;
1344                 close_bdev_exclusive(bdev, mode);
1345         } else {
1346                 char b[BDEVNAME_SIZE];
1347
1348                 s->s_flags = flags;
1349                 s->s_mode = mode;
1350                 strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
1351                 sb_set_blocksize(s, block_size(bdev));
1352                 error = fill_super(s, &args, flags & MS_SILENT ? 1 : 0);
1353                 if (error) {
1354                         deactivate_locked_super(s);
1355                         return error;
1356                 }
1357                 s->s_flags |= MS_ACTIVE;
1358                 bdev->bd_super = s;
1359         }
1360
1361         sdp = s->s_fs_info;
1362         mnt->mnt_sb = s;
1363         if (args.ar_meta)
1364                 mnt->mnt_root = dget(sdp->sd_master_dir);
1365         else
1366                 mnt->mnt_root = dget(sdp->sd_root_dir);
1367         return 0;
1368
1369 error_super:
1370         deactivate_locked_super(s);
1371 error_bdev:
1372         close_bdev_exclusive(bdev, mode);
1373         return error;
1374 }
1375
1376 static int set_meta_super(struct super_block *s, void *ptr)
1377 {
1378         return -EINVAL;
1379 }
1380
1381 static int gfs2_get_sb_meta(struct file_system_type *fs_type, int flags,
1382                             const char *dev_name, void *data, struct vfsmount *mnt)
1383 {
1384         struct super_block *s;
1385         struct gfs2_sbd *sdp;
1386         struct path path;
1387         int error;
1388
1389         error = kern_path(dev_name, LOOKUP_FOLLOW, &path);
1390         if (error) {
1391                 printk(KERN_WARNING "GFS2: path_lookup on %s returned error %d\n",
1392                        dev_name, error);
1393                 return error;
1394         }
1395         s = sget(&gfs2_fs_type, test_gfs2_super, set_meta_super,
1396                  path.dentry->d_inode->i_sb->s_bdev);
1397         path_put(&path);
1398         if (IS_ERR(s)) {
1399                 printk(KERN_WARNING "GFS2: gfs2 mount does not exist\n");
1400                 return PTR_ERR(s);
1401         }
1402         if ((flags ^ s->s_flags) & MS_RDONLY) {
1403                 deactivate_locked_super(s);
1404                 return -EBUSY;
1405         }
1406         sdp = s->s_fs_info;
1407         mnt->mnt_sb = s;
1408         mnt->mnt_root = dget(sdp->sd_master_dir);
1409         return 0;
1410 }
1411
1412 static void gfs2_kill_sb(struct super_block *sb)
1413 {
1414         struct gfs2_sbd *sdp = sb->s_fs_info;
1415
1416         if (sdp == NULL) {
1417                 kill_block_super(sb);
1418                 return;
1419         }
1420
1421         gfs2_meta_syncfs(sdp);
1422         dput(sdp->sd_root_dir);
1423         dput(sdp->sd_master_dir);
1424         sdp->sd_root_dir = NULL;
1425         sdp->sd_master_dir = NULL;
1426         shrink_dcache_sb(sb);
1427         kill_block_super(sb);
1428         gfs2_delete_debugfs_file(sdp);
1429         kfree(sdp);
1430 }
1431
1432 struct file_system_type gfs2_fs_type = {
1433         .name = "gfs2",
1434         .fs_flags = FS_REQUIRES_DEV,
1435         .get_sb = gfs2_get_sb,
1436         .kill_sb = gfs2_kill_sb,
1437         .owner = THIS_MODULE,
1438 };
1439
1440 struct file_system_type gfs2meta_fs_type = {
1441         .name = "gfs2meta",
1442         .fs_flags = FS_REQUIRES_DEV,
1443         .get_sb = gfs2_get_sb_meta,
1444         .owner = THIS_MODULE,
1445 };
1446