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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12 #include <linux/sched.h>
13 #include <linux/slab.h>
14 #include <linux/spinlock.h>
15 #include <linux/completion.h>
16 #include <linux/buffer_head.h>
17 #include <linux/blkdev.h>
18 #include <linux/kthread.h>
19 #include <linux/export.h>
20 #include <linux/namei.h>
21 #include <linux/mount.h>
22 #include <linux/gfs2_ondisk.h>
23 #include <linux/quotaops.h>
24 #include <linux/lockdep.h>
25 #include <linux/module.h>
26
27 #include "gfs2.h"
28 #include "incore.h"
29 #include "bmap.h"
30 #include "glock.h"
31 #include "glops.h"
32 #include "inode.h"
33 #include "recovery.h"
34 #include "rgrp.h"
35 #include "super.h"
36 #include "sys.h"
37 #include "util.h"
38 #include "log.h"
39 #include "quota.h"
40 #include "dir.h"
41 #include "meta_io.h"
42 #include "trace_gfs2.h"
43
44 #define DO 0
45 #define UNDO 1
46
47 /**
48 * gfs2_tune_init - Fill a gfs2_tune structure with default values
49 * @gt: tune
50 *
51 */
52
gfs2_tune_init(struct gfs2_tune * gt)53 static void gfs2_tune_init(struct gfs2_tune *gt)
54 {
55 spin_lock_init(>->gt_spin);
56
57 gt->gt_quota_warn_period = 10;
58 gt->gt_quota_scale_num = 1;
59 gt->gt_quota_scale_den = 1;
60 gt->gt_new_files_jdata = 0;
61 gt->gt_max_readahead = 1 << 18;
62 gt->gt_complain_secs = 10;
63 }
64
init_sbd(struct super_block * sb)65 static struct gfs2_sbd *init_sbd(struct super_block *sb)
66 {
67 struct gfs2_sbd *sdp;
68 struct address_space *mapping;
69
70 sdp = kzalloc(sizeof(struct gfs2_sbd), GFP_KERNEL);
71 if (!sdp)
72 return NULL;
73
74 sdp->sd_vfs = sb;
75 sdp->sd_lkstats = alloc_percpu(struct gfs2_pcpu_lkstats);
76 if (!sdp->sd_lkstats) {
77 kfree(sdp);
78 return NULL;
79 }
80 sb->s_fs_info = sdp;
81
82 set_bit(SDF_NOJOURNALID, &sdp->sd_flags);
83 gfs2_tune_init(&sdp->sd_tune);
84
85 init_waitqueue_head(&sdp->sd_glock_wait);
86 atomic_set(&sdp->sd_glock_disposal, 0);
87 init_completion(&sdp->sd_locking_init);
88 init_completion(&sdp->sd_wdack);
89 spin_lock_init(&sdp->sd_statfs_spin);
90
91 spin_lock_init(&sdp->sd_rindex_spin);
92 sdp->sd_rindex_tree.rb_node = NULL;
93
94 INIT_LIST_HEAD(&sdp->sd_jindex_list);
95 spin_lock_init(&sdp->sd_jindex_spin);
96 mutex_init(&sdp->sd_jindex_mutex);
97 init_completion(&sdp->sd_journal_ready);
98
99 INIT_LIST_HEAD(&sdp->sd_quota_list);
100 mutex_init(&sdp->sd_quota_mutex);
101 mutex_init(&sdp->sd_quota_sync_mutex);
102 init_waitqueue_head(&sdp->sd_quota_wait);
103 INIT_LIST_HEAD(&sdp->sd_trunc_list);
104 spin_lock_init(&sdp->sd_trunc_lock);
105 spin_lock_init(&sdp->sd_bitmap_lock);
106
107 mapping = &sdp->sd_aspace;
108
109 address_space_init_once(mapping);
110 mapping->a_ops = &gfs2_rgrp_aops;
111 mapping->host = sb->s_bdev->bd_inode;
112 mapping->flags = 0;
113 mapping_set_gfp_mask(mapping, GFP_NOFS);
114 mapping->private_data = NULL;
115 mapping->writeback_index = 0;
116
117 spin_lock_init(&sdp->sd_log_lock);
118 atomic_set(&sdp->sd_log_pinned, 0);
119 INIT_LIST_HEAD(&sdp->sd_log_le_revoke);
120 INIT_LIST_HEAD(&sdp->sd_log_le_ordered);
121 spin_lock_init(&sdp->sd_ordered_lock);
122
123 init_waitqueue_head(&sdp->sd_log_waitq);
124 init_waitqueue_head(&sdp->sd_logd_waitq);
125 spin_lock_init(&sdp->sd_ail_lock);
126 INIT_LIST_HEAD(&sdp->sd_ail1_list);
127 INIT_LIST_HEAD(&sdp->sd_ail2_list);
128
129 init_rwsem(&sdp->sd_log_flush_lock);
130 atomic_set(&sdp->sd_log_in_flight, 0);
131 atomic_set(&sdp->sd_reserving_log, 0);
132 init_waitqueue_head(&sdp->sd_reserving_log_wait);
133 init_waitqueue_head(&sdp->sd_log_flush_wait);
134 atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
135 mutex_init(&sdp->sd_freeze_mutex);
136
137 return sdp;
138 }
139
140
141 /**
142 * gfs2_check_sb - Check superblock
143 * @sdp: the filesystem
144 * @sb: The superblock
145 * @silent: Don't print a message if the check fails
146 *
147 * Checks the version code of the FS is one that we understand how to
148 * read and that the sizes of the various on-disk structures have not
149 * changed.
150 */
151
gfs2_check_sb(struct gfs2_sbd * sdp,int silent)152 static int gfs2_check_sb(struct gfs2_sbd *sdp, int silent)
153 {
154 struct gfs2_sb_host *sb = &sdp->sd_sb;
155
156 if (sb->sb_magic != GFS2_MAGIC ||
157 sb->sb_type != GFS2_METATYPE_SB) {
158 if (!silent)
159 pr_warn("not a GFS2 filesystem\n");
160 return -EINVAL;
161 }
162
163 if (sb->sb_fs_format != GFS2_FORMAT_FS ||
164 sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
165 fs_warn(sdp, "Unknown on-disk format, unable to mount\n");
166 return -EINVAL;
167 }
168
169 if (sb->sb_bsize < 512 || sb->sb_bsize > PAGE_SIZE ||
170 (sb->sb_bsize & (sb->sb_bsize - 1))) {
171 pr_warn("Invalid superblock size\n");
172 return -EINVAL;
173 }
174
175 return 0;
176 }
177
end_bio_io_page(struct bio * bio)178 static void end_bio_io_page(struct bio *bio)
179 {
180 struct page *page = bio->bi_private;
181
182 if (!bio->bi_error)
183 SetPageUptodate(page);
184 else
185 pr_warn("error %d reading superblock\n", bio->bi_error);
186 unlock_page(page);
187 }
188
gfs2_sb_in(struct gfs2_sbd * sdp,const void * buf)189 static void gfs2_sb_in(struct gfs2_sbd *sdp, const void *buf)
190 {
191 struct gfs2_sb_host *sb = &sdp->sd_sb;
192 struct super_block *s = sdp->sd_vfs;
193 const struct gfs2_sb *str = buf;
194
195 sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
196 sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
197 sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
198 sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
199 sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
200 sb->sb_bsize = be32_to_cpu(str->sb_bsize);
201 sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
202 sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
203 sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
204 sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
205 sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
206
207 memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
208 memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
209 memcpy(s->s_uuid, str->sb_uuid, 16);
210 }
211
212 /**
213 * gfs2_read_super - Read the gfs2 super block from disk
214 * @sdp: The GFS2 super block
215 * @sector: The location of the super block
216 * @error: The error code to return
217 *
218 * This uses the bio functions to read the super block from disk
219 * because we want to be 100% sure that we never read cached data.
220 * A super block is read twice only during each GFS2 mount and is
221 * never written to by the filesystem. The first time its read no
222 * locks are held, and the only details which are looked at are those
223 * relating to the locking protocol. Once locking is up and working,
224 * the sb is read again under the lock to establish the location of
225 * the master directory (contains pointers to journals etc) and the
226 * root directory.
227 *
228 * Returns: 0 on success or error
229 */
230
gfs2_read_super(struct gfs2_sbd * sdp,sector_t sector,int silent)231 static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector, int silent)
232 {
233 struct super_block *sb = sdp->sd_vfs;
234 struct gfs2_sb *p;
235 struct page *page;
236 struct bio *bio;
237
238 page = alloc_page(GFP_NOFS);
239 if (unlikely(!page))
240 return -ENOMEM;
241
242 ClearPageUptodate(page);
243 ClearPageDirty(page);
244 lock_page(page);
245
246 bio = bio_alloc(GFP_NOFS, 1);
247 bio->bi_iter.bi_sector = sector * (sb->s_blocksize >> 9);
248 bio->bi_bdev = sb->s_bdev;
249 bio_add_page(bio, page, PAGE_SIZE, 0);
250
251 bio->bi_end_io = end_bio_io_page;
252 bio->bi_private = page;
253 submit_bio(READ_SYNC | REQ_META, bio);
254 wait_on_page_locked(page);
255 bio_put(bio);
256 if (!PageUptodate(page)) {
257 __free_page(page);
258 return -EIO;
259 }
260 p = kmap(page);
261 gfs2_sb_in(sdp, p);
262 kunmap(page);
263 __free_page(page);
264 return gfs2_check_sb(sdp, silent);
265 }
266
267 /**
268 * gfs2_read_sb - Read super block
269 * @sdp: The GFS2 superblock
270 * @silent: Don't print message if mount fails
271 *
272 */
273
gfs2_read_sb(struct gfs2_sbd * sdp,int silent)274 static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
275 {
276 u32 hash_blocks, ind_blocks, leaf_blocks;
277 u32 tmp_blocks;
278 unsigned int x;
279 int error;
280
281 error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
282 if (error) {
283 if (!silent)
284 fs_err(sdp, "can't read superblock\n");
285 return error;
286 }
287
288 sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
289 GFS2_BASIC_BLOCK_SHIFT;
290 sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
291 sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
292 sizeof(struct gfs2_dinode)) / sizeof(u64);
293 sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
294 sizeof(struct gfs2_meta_header)) / sizeof(u64);
295 sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
296 sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
297 sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
298 sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
299 sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
300 sizeof(struct gfs2_meta_header)) /
301 sizeof(struct gfs2_quota_change);
302 sdp->sd_blocks_per_bitmap = (sdp->sd_sb.sb_bsize -
303 sizeof(struct gfs2_meta_header))
304 * GFS2_NBBY; /* not the rgrp bitmap, subsequent bitmaps only */
305
306 /* Compute maximum reservation required to add a entry to a directory */
307
308 hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << GFS2_DIR_MAX_DEPTH),
309 sdp->sd_jbsize);
310
311 ind_blocks = 0;
312 for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
313 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
314 ind_blocks += tmp_blocks;
315 }
316
317 leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
318
319 sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
320
321 sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
322 sizeof(struct gfs2_dinode);
323 sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
324 for (x = 2;; x++) {
325 u64 space, d;
326 u32 m;
327
328 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
329 d = space;
330 m = do_div(d, sdp->sd_inptrs);
331
332 if (d != sdp->sd_heightsize[x - 1] || m)
333 break;
334 sdp->sd_heightsize[x] = space;
335 }
336 sdp->sd_max_height = x;
337 sdp->sd_heightsize[x] = ~0;
338 gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
339
340 sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
341 sizeof(struct gfs2_dinode);
342 sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
343 for (x = 2;; x++) {
344 u64 space, d;
345 u32 m;
346
347 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
348 d = space;
349 m = do_div(d, sdp->sd_inptrs);
350
351 if (d != sdp->sd_jheightsize[x - 1] || m)
352 break;
353 sdp->sd_jheightsize[x] = space;
354 }
355 sdp->sd_max_jheight = x;
356 sdp->sd_jheightsize[x] = ~0;
357 gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
358
359 return 0;
360 }
361
init_names(struct gfs2_sbd * sdp,int silent)362 static int init_names(struct gfs2_sbd *sdp, int silent)
363 {
364 char *proto, *table;
365 int error = 0;
366
367 proto = sdp->sd_args.ar_lockproto;
368 table = sdp->sd_args.ar_locktable;
369
370 /* Try to autodetect */
371
372 if (!proto[0] || !table[0]) {
373 error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
374 if (error)
375 return error;
376
377 if (!proto[0])
378 proto = sdp->sd_sb.sb_lockproto;
379 if (!table[0])
380 table = sdp->sd_sb.sb_locktable;
381 }
382
383 if (!table[0])
384 table = sdp->sd_vfs->s_id;
385
386 strlcpy(sdp->sd_proto_name, proto, GFS2_FSNAME_LEN);
387 strlcpy(sdp->sd_table_name, table, GFS2_FSNAME_LEN);
388
389 table = sdp->sd_table_name;
390 while ((table = strchr(table, '/')))
391 *table = '_';
392
393 return error;
394 }
395
init_locking(struct gfs2_sbd * sdp,struct gfs2_holder * mount_gh,int undo)396 static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
397 int undo)
398 {
399 int error = 0;
400
401 if (undo)
402 goto fail_trans;
403
404 error = gfs2_glock_nq_num(sdp,
405 GFS2_MOUNT_LOCK, &gfs2_nondisk_glops,
406 LM_ST_EXCLUSIVE, LM_FLAG_NOEXP | GL_NOCACHE,
407 mount_gh);
408 if (error) {
409 fs_err(sdp, "can't acquire mount glock: %d\n", error);
410 goto fail;
411 }
412
413 error = gfs2_glock_nq_num(sdp,
414 GFS2_LIVE_LOCK, &gfs2_nondisk_glops,
415 LM_ST_SHARED,
416 LM_FLAG_NOEXP | GL_EXACT,
417 &sdp->sd_live_gh);
418 if (error) {
419 fs_err(sdp, "can't acquire live glock: %d\n", error);
420 goto fail_mount;
421 }
422
423 error = gfs2_glock_get(sdp, GFS2_RENAME_LOCK, &gfs2_nondisk_glops,
424 CREATE, &sdp->sd_rename_gl);
425 if (error) {
426 fs_err(sdp, "can't create rename glock: %d\n", error);
427 goto fail_live;
428 }
429
430 error = gfs2_glock_get(sdp, GFS2_FREEZE_LOCK, &gfs2_freeze_glops,
431 CREATE, &sdp->sd_freeze_gl);
432 if (error) {
433 fs_err(sdp, "can't create transaction glock: %d\n", error);
434 goto fail_rename;
435 }
436
437 return 0;
438
439 fail_trans:
440 gfs2_glock_put(sdp->sd_freeze_gl);
441 fail_rename:
442 gfs2_glock_put(sdp->sd_rename_gl);
443 fail_live:
444 gfs2_glock_dq_uninit(&sdp->sd_live_gh);
445 fail_mount:
446 gfs2_glock_dq_uninit(mount_gh);
447 fail:
448 return error;
449 }
450
gfs2_lookup_root(struct super_block * sb,struct dentry ** dptr,u64 no_addr,const char * name)451 static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
452 u64 no_addr, const char *name)
453 {
454 struct gfs2_sbd *sdp = sb->s_fs_info;
455 struct dentry *dentry;
456 struct inode *inode;
457
458 inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0, 0);
459 if (IS_ERR(inode)) {
460 fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
461 return PTR_ERR(inode);
462 }
463 dentry = d_make_root(inode);
464 if (!dentry) {
465 fs_err(sdp, "can't alloc %s dentry\n", name);
466 return -ENOMEM;
467 }
468 *dptr = dentry;
469 return 0;
470 }
471
init_sb(struct gfs2_sbd * sdp,int silent)472 static int init_sb(struct gfs2_sbd *sdp, int silent)
473 {
474 struct super_block *sb = sdp->sd_vfs;
475 struct gfs2_holder sb_gh;
476 u64 no_addr;
477 int ret;
478
479 ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
480 LM_ST_SHARED, 0, &sb_gh);
481 if (ret) {
482 fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
483 return ret;
484 }
485
486 ret = gfs2_read_sb(sdp, silent);
487 if (ret) {
488 fs_err(sdp, "can't read superblock: %d\n", ret);
489 goto out;
490 }
491
492 /* Set up the buffer cache and SB for real */
493 if (sdp->sd_sb.sb_bsize < bdev_logical_block_size(sb->s_bdev)) {
494 ret = -EINVAL;
495 fs_err(sdp, "FS block size (%u) is too small for device "
496 "block size (%u)\n",
497 sdp->sd_sb.sb_bsize, bdev_logical_block_size(sb->s_bdev));
498 goto out;
499 }
500 if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
501 ret = -EINVAL;
502 fs_err(sdp, "FS block size (%u) is too big for machine "
503 "page size (%u)\n",
504 sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
505 goto out;
506 }
507 sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
508
509 /* Get the root inode */
510 no_addr = sdp->sd_sb.sb_root_dir.no_addr;
511 ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
512 if (ret)
513 goto out;
514
515 /* Get the master inode */
516 no_addr = sdp->sd_sb.sb_master_dir.no_addr;
517 ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
518 if (ret) {
519 dput(sdp->sd_root_dir);
520 goto out;
521 }
522 sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
523 out:
524 gfs2_glock_dq_uninit(&sb_gh);
525 return ret;
526 }
527
gfs2_others_may_mount(struct gfs2_sbd * sdp)528 static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
529 {
530 char *message = "FIRSTMOUNT=Done";
531 char *envp[] = { message, NULL };
532
533 fs_info(sdp, "first mount done, others may mount\n");
534
535 if (sdp->sd_lockstruct.ls_ops->lm_first_done)
536 sdp->sd_lockstruct.ls_ops->lm_first_done(sdp);
537
538 kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
539 }
540
541 /**
542 * gfs2_jindex_hold - Grab a lock on the jindex
543 * @sdp: The GFS2 superblock
544 * @ji_gh: the holder for the jindex glock
545 *
546 * Returns: errno
547 */
548
gfs2_jindex_hold(struct gfs2_sbd * sdp,struct gfs2_holder * ji_gh)549 static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
550 {
551 struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
552 struct qstr name;
553 char buf[20];
554 struct gfs2_jdesc *jd;
555 int error;
556
557 name.name = buf;
558
559 mutex_lock(&sdp->sd_jindex_mutex);
560
561 for (;;) {
562 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
563 if (error)
564 break;
565
566 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
567 name.hash = gfs2_disk_hash(name.name, name.len);
568
569 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
570 if (error == -ENOENT) {
571 error = 0;
572 break;
573 }
574
575 gfs2_glock_dq_uninit(ji_gh);
576
577 if (error)
578 break;
579
580 error = -ENOMEM;
581 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
582 if (!jd)
583 break;
584
585 INIT_LIST_HEAD(&jd->extent_list);
586 INIT_LIST_HEAD(&jd->jd_revoke_list);
587
588 INIT_WORK(&jd->jd_work, gfs2_recover_func);
589 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
590 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
591 if (!jd->jd_inode)
592 error = -ENOENT;
593 else
594 error = PTR_ERR(jd->jd_inode);
595 kfree(jd);
596 break;
597 }
598
599 spin_lock(&sdp->sd_jindex_spin);
600 jd->jd_jid = sdp->sd_journals++;
601 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
602 spin_unlock(&sdp->sd_jindex_spin);
603 }
604
605 mutex_unlock(&sdp->sd_jindex_mutex);
606
607 return error;
608 }
609
610 /**
611 * check_journal_clean - Make sure a journal is clean for a spectator mount
612 * @sdp: The GFS2 superblock
613 * @jd: The journal descriptor
614 *
615 * Returns: 0 if the journal is clean or locked, else an error
616 */
check_journal_clean(struct gfs2_sbd * sdp,struct gfs2_jdesc * jd)617 static int check_journal_clean(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd)
618 {
619 int error;
620 struct gfs2_holder j_gh;
621 struct gfs2_log_header_host head;
622 struct gfs2_inode *ip;
623
624 ip = GFS2_I(jd->jd_inode);
625 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_NOEXP |
626 GL_EXACT | GL_NOCACHE, &j_gh);
627 if (error) {
628 fs_err(sdp, "Error locking journal for spectator mount.\n");
629 return -EPERM;
630 }
631 error = gfs2_jdesc_check(jd);
632 if (error) {
633 fs_err(sdp, "Error checking journal for spectator mount.\n");
634 goto out_unlock;
635 }
636 error = gfs2_find_jhead(jd, &head);
637 if (error) {
638 fs_err(sdp, "Error parsing journal for spectator mount.\n");
639 goto out_unlock;
640 }
641 if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
642 error = -EPERM;
643 fs_err(sdp, "jid=%u: Journal is dirty, so the first mounter "
644 "must not be a spectator.\n", jd->jd_jid);
645 }
646
647 out_unlock:
648 gfs2_glock_dq_uninit(&j_gh);
649 return error;
650 }
651
init_journal(struct gfs2_sbd * sdp,int undo)652 static int init_journal(struct gfs2_sbd *sdp, int undo)
653 {
654 struct inode *master = d_inode(sdp->sd_master_dir);
655 struct gfs2_holder ji_gh;
656 struct gfs2_inode *ip;
657 int jindex = 1;
658 int error = 0;
659
660 if (undo) {
661 jindex = 0;
662 goto fail_jinode_gh;
663 }
664
665 sdp->sd_jindex = gfs2_lookup_simple(master, "jindex");
666 if (IS_ERR(sdp->sd_jindex)) {
667 fs_err(sdp, "can't lookup journal index: %d\n", error);
668 return PTR_ERR(sdp->sd_jindex);
669 }
670
671 /* Load in the journal index special file */
672
673 error = gfs2_jindex_hold(sdp, &ji_gh);
674 if (error) {
675 fs_err(sdp, "can't read journal index: %d\n", error);
676 goto fail;
677 }
678
679 error = -EUSERS;
680 if (!gfs2_jindex_size(sdp)) {
681 fs_err(sdp, "no journals!\n");
682 goto fail_jindex;
683 }
684
685 if (sdp->sd_args.ar_spectator) {
686 sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
687 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
688 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
689 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
690 } else {
691 if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
692 fs_err(sdp, "can't mount journal #%u\n",
693 sdp->sd_lockstruct.ls_jid);
694 fs_err(sdp, "there are only %u journals (0 - %u)\n",
695 gfs2_jindex_size(sdp),
696 gfs2_jindex_size(sdp) - 1);
697 goto fail_jindex;
698 }
699 sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);
700
701 error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
702 &gfs2_journal_glops,
703 LM_ST_EXCLUSIVE, LM_FLAG_NOEXP,
704 &sdp->sd_journal_gh);
705 if (error) {
706 fs_err(sdp, "can't acquire journal glock: %d\n", error);
707 goto fail_jindex;
708 }
709
710 ip = GFS2_I(sdp->sd_jdesc->jd_inode);
711 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
712 LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE,
713 &sdp->sd_jinode_gh);
714 if (error) {
715 fs_err(sdp, "can't acquire journal inode glock: %d\n",
716 error);
717 goto fail_journal_gh;
718 }
719
720 error = gfs2_jdesc_check(sdp->sd_jdesc);
721 if (error) {
722 fs_err(sdp, "my journal (%u) is bad: %d\n",
723 sdp->sd_jdesc->jd_jid, error);
724 goto fail_jinode_gh;
725 }
726 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
727 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
728 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
729
730 /* Map the extents for this journal's blocks */
731 gfs2_map_journal_extents(sdp, sdp->sd_jdesc);
732 }
733 trace_gfs2_log_blocks(sdp, atomic_read(&sdp->sd_log_blks_free));
734
735 if (sdp->sd_lockstruct.ls_first) {
736 unsigned int x;
737 for (x = 0; x < sdp->sd_journals; x++) {
738 struct gfs2_jdesc *jd = gfs2_jdesc_find(sdp, x);
739
740 if (sdp->sd_args.ar_spectator) {
741 error = check_journal_clean(sdp, jd);
742 if (error)
743 goto fail_jinode_gh;
744 continue;
745 }
746 error = gfs2_recover_journal(jd, true);
747 if (error) {
748 fs_err(sdp, "error recovering journal %u: %d\n",
749 x, error);
750 goto fail_jinode_gh;
751 }
752 }
753
754 gfs2_others_may_mount(sdp);
755 } else if (!sdp->sd_args.ar_spectator) {
756 error = gfs2_recover_journal(sdp->sd_jdesc, true);
757 if (error) {
758 fs_err(sdp, "error recovering my journal: %d\n", error);
759 goto fail_jinode_gh;
760 }
761 }
762
763 sdp->sd_log_idle = 1;
764 set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
765 gfs2_glock_dq_uninit(&ji_gh);
766 jindex = 0;
767 INIT_WORK(&sdp->sd_freeze_work, gfs2_freeze_func);
768 return 0;
769
770 fail_jinode_gh:
771 if (!sdp->sd_args.ar_spectator)
772 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
773 fail_journal_gh:
774 if (!sdp->sd_args.ar_spectator)
775 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
776 fail_jindex:
777 gfs2_jindex_free(sdp);
778 if (jindex)
779 gfs2_glock_dq_uninit(&ji_gh);
780 fail:
781 iput(sdp->sd_jindex);
782 return error;
783 }
784
785 static struct lock_class_key gfs2_quota_imutex_key;
786
init_inodes(struct gfs2_sbd * sdp,int undo)787 static int init_inodes(struct gfs2_sbd *sdp, int undo)
788 {
789 int error = 0;
790 struct inode *master = d_inode(sdp->sd_master_dir);
791
792 if (undo)
793 goto fail_qinode;
794
795 error = init_journal(sdp, undo);
796 complete_all(&sdp->sd_journal_ready);
797 if (error)
798 goto fail;
799
800 /* Read in the master statfs inode */
801 sdp->sd_statfs_inode = gfs2_lookup_simple(master, "statfs");
802 if (IS_ERR(sdp->sd_statfs_inode)) {
803 error = PTR_ERR(sdp->sd_statfs_inode);
804 fs_err(sdp, "can't read in statfs inode: %d\n", error);
805 goto fail_journal;
806 }
807
808 /* Read in the resource index inode */
809 sdp->sd_rindex = gfs2_lookup_simple(master, "rindex");
810 if (IS_ERR(sdp->sd_rindex)) {
811 error = PTR_ERR(sdp->sd_rindex);
812 fs_err(sdp, "can't get resource index inode: %d\n", error);
813 goto fail_statfs;
814 }
815 sdp->sd_rindex_uptodate = 0;
816
817 /* Read in the quota inode */
818 sdp->sd_quota_inode = gfs2_lookup_simple(master, "quota");
819 if (IS_ERR(sdp->sd_quota_inode)) {
820 error = PTR_ERR(sdp->sd_quota_inode);
821 fs_err(sdp, "can't get quota file inode: %d\n", error);
822 goto fail_rindex;
823 }
824 /*
825 * i_mutex on quota files is special. Since this inode is hidden system
826 * file, we are safe to define locking ourselves.
827 */
828 lockdep_set_class(&sdp->sd_quota_inode->i_mutex,
829 &gfs2_quota_imutex_key);
830
831 error = gfs2_rindex_update(sdp);
832 if (error)
833 goto fail_qinode;
834
835 return 0;
836
837 fail_qinode:
838 iput(sdp->sd_quota_inode);
839 fail_rindex:
840 gfs2_clear_rgrpd(sdp);
841 iput(sdp->sd_rindex);
842 fail_statfs:
843 iput(sdp->sd_statfs_inode);
844 fail_journal:
845 init_journal(sdp, UNDO);
846 fail:
847 return error;
848 }
849
init_per_node(struct gfs2_sbd * sdp,int undo)850 static int init_per_node(struct gfs2_sbd *sdp, int undo)
851 {
852 struct inode *pn = NULL;
853 char buf[30];
854 int error = 0;
855 struct gfs2_inode *ip;
856 struct inode *master = d_inode(sdp->sd_master_dir);
857
858 if (sdp->sd_args.ar_spectator)
859 return 0;
860
861 if (undo)
862 goto fail_qc_gh;
863
864 pn = gfs2_lookup_simple(master, "per_node");
865 if (IS_ERR(pn)) {
866 error = PTR_ERR(pn);
867 fs_err(sdp, "can't find per_node directory: %d\n", error);
868 return error;
869 }
870
871 sprintf(buf, "statfs_change%u", sdp->sd_jdesc->jd_jid);
872 sdp->sd_sc_inode = gfs2_lookup_simple(pn, buf);
873 if (IS_ERR(sdp->sd_sc_inode)) {
874 error = PTR_ERR(sdp->sd_sc_inode);
875 fs_err(sdp, "can't find local \"sc\" file: %d\n", error);
876 goto fail;
877 }
878
879 sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
880 sdp->sd_qc_inode = gfs2_lookup_simple(pn, buf);
881 if (IS_ERR(sdp->sd_qc_inode)) {
882 error = PTR_ERR(sdp->sd_qc_inode);
883 fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
884 goto fail_ut_i;
885 }
886
887 iput(pn);
888 pn = NULL;
889
890 ip = GFS2_I(sdp->sd_sc_inode);
891 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
892 &sdp->sd_sc_gh);
893 if (error) {
894 fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
895 goto fail_qc_i;
896 }
897
898 ip = GFS2_I(sdp->sd_qc_inode);
899 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
900 &sdp->sd_qc_gh);
901 if (error) {
902 fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
903 goto fail_ut_gh;
904 }
905
906 return 0;
907
908 fail_qc_gh:
909 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
910 fail_ut_gh:
911 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
912 fail_qc_i:
913 iput(sdp->sd_qc_inode);
914 fail_ut_i:
915 iput(sdp->sd_sc_inode);
916 fail:
917 if (pn)
918 iput(pn);
919 return error;
920 }
921
922 static const match_table_t nolock_tokens = {
923 { Opt_jid, "jid=%d", },
924 { Opt_err, NULL },
925 };
926
927 static const struct lm_lockops nolock_ops = {
928 .lm_proto_name = "lock_nolock",
929 .lm_put_lock = gfs2_glock_free,
930 .lm_tokens = &nolock_tokens,
931 };
932
933 /**
934 * gfs2_lm_mount - mount a locking protocol
935 * @sdp: the filesystem
936 * @args: mount arguments
937 * @silent: if 1, don't complain if the FS isn't a GFS2 fs
938 *
939 * Returns: errno
940 */
941
gfs2_lm_mount(struct gfs2_sbd * sdp,int silent)942 static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
943 {
944 const struct lm_lockops *lm;
945 struct lm_lockstruct *ls = &sdp->sd_lockstruct;
946 struct gfs2_args *args = &sdp->sd_args;
947 const char *proto = sdp->sd_proto_name;
948 const char *table = sdp->sd_table_name;
949 char *o, *options;
950 int ret;
951
952 if (!strcmp("lock_nolock", proto)) {
953 lm = &nolock_ops;
954 sdp->sd_args.ar_localflocks = 1;
955 #ifdef CONFIG_GFS2_FS_LOCKING_DLM
956 } else if (!strcmp("lock_dlm", proto)) {
957 lm = &gfs2_dlm_ops;
958 #endif
959 } else {
960 pr_info("can't find protocol %s\n", proto);
961 return -ENOENT;
962 }
963
964 fs_info(sdp, "Trying to join cluster \"%s\", \"%s\"\n", proto, table);
965
966 ls->ls_ops = lm;
967 ls->ls_first = 1;
968
969 for (options = args->ar_hostdata; (o = strsep(&options, ":")); ) {
970 substring_t tmp[MAX_OPT_ARGS];
971 int token, option;
972
973 if (!o || !*o)
974 continue;
975
976 token = match_token(o, *lm->lm_tokens, tmp);
977 switch (token) {
978 case Opt_jid:
979 ret = match_int(&tmp[0], &option);
980 if (ret || option < 0)
981 goto hostdata_error;
982 if (test_and_clear_bit(SDF_NOJOURNALID, &sdp->sd_flags))
983 ls->ls_jid = option;
984 break;
985 case Opt_id:
986 case Opt_nodir:
987 /* Obsolete, but left for backward compat purposes */
988 break;
989 case Opt_first:
990 ret = match_int(&tmp[0], &option);
991 if (ret || (option != 0 && option != 1))
992 goto hostdata_error;
993 ls->ls_first = option;
994 break;
995 case Opt_err:
996 default:
997 hostdata_error:
998 fs_info(sdp, "unknown hostdata (%s)\n", o);
999 return -EINVAL;
1000 }
1001 }
1002
1003 if (lm->lm_mount == NULL) {
1004 fs_info(sdp, "Now mounting FS...\n");
1005 complete_all(&sdp->sd_locking_init);
1006 return 0;
1007 }
1008 ret = lm->lm_mount(sdp, table);
1009 if (ret == 0)
1010 fs_info(sdp, "Joined cluster. Now mounting FS...\n");
1011 complete_all(&sdp->sd_locking_init);
1012 return ret;
1013 }
1014
gfs2_lm_unmount(struct gfs2_sbd * sdp)1015 void gfs2_lm_unmount(struct gfs2_sbd *sdp)
1016 {
1017 const struct lm_lockops *lm = sdp->sd_lockstruct.ls_ops;
1018 if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) &&
1019 lm->lm_unmount)
1020 lm->lm_unmount(sdp);
1021 }
1022
wait_on_journal(struct gfs2_sbd * sdp)1023 static int wait_on_journal(struct gfs2_sbd *sdp)
1024 {
1025 if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
1026 return 0;
1027
1028 return wait_on_bit(&sdp->sd_flags, SDF_NOJOURNALID, TASK_INTERRUPTIBLE)
1029 ? -EINTR : 0;
1030 }
1031
gfs2_online_uevent(struct gfs2_sbd * sdp)1032 void gfs2_online_uevent(struct gfs2_sbd *sdp)
1033 {
1034 struct super_block *sb = sdp->sd_vfs;
1035 char ro[20];
1036 char spectator[20];
1037 char *envp[] = { ro, spectator, NULL };
1038 sprintf(ro, "RDONLY=%d", (sb->s_flags & MS_RDONLY) ? 1 : 0);
1039 sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
1040 kobject_uevent_env(&sdp->sd_kobj, KOBJ_ONLINE, envp);
1041 }
1042
1043 /**
1044 * fill_super - Read in superblock
1045 * @sb: The VFS superblock
1046 * @data: Mount options
1047 * @silent: Don't complain if it's not a GFS2 filesystem
1048 *
1049 * Returns: errno
1050 */
1051
fill_super(struct super_block * sb,struct gfs2_args * args,int silent)1052 static int fill_super(struct super_block *sb, struct gfs2_args *args, int silent)
1053 {
1054 struct gfs2_sbd *sdp;
1055 struct gfs2_holder mount_gh;
1056 int error;
1057
1058 sdp = init_sbd(sb);
1059 if (!sdp) {
1060 pr_warn("can't alloc struct gfs2_sbd\n");
1061 return -ENOMEM;
1062 }
1063 sdp->sd_args = *args;
1064
1065 if (sdp->sd_args.ar_spectator) {
1066 sb->s_flags |= MS_RDONLY;
1067 set_bit(SDF_RORECOVERY, &sdp->sd_flags);
1068 }
1069 if (sdp->sd_args.ar_posix_acl)
1070 sb->s_flags |= MS_POSIXACL;
1071 if (sdp->sd_args.ar_nobarrier)
1072 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1073
1074 sb->s_flags |= MS_NOSEC;
1075 sb->s_magic = GFS2_MAGIC;
1076 sb->s_op = &gfs2_super_ops;
1077 sb->s_d_op = &gfs2_dops;
1078 sb->s_export_op = &gfs2_export_ops;
1079 sb->s_xattr = gfs2_xattr_handlers;
1080 sb->s_qcop = &gfs2_quotactl_ops;
1081 sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1082 sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
1083 sb->s_time_gran = 1;
1084 sb->s_maxbytes = MAX_LFS_FILESIZE;
1085
1086 /* Set up the buffer cache and fill in some fake block size values
1087 to allow us to read-in the on-disk superblock. */
1088 sdp->sd_sb.sb_bsize = sb_min_blocksize(sb, GFS2_BASIC_BLOCK);
1089 sdp->sd_sb.sb_bsize_shift = sb->s_blocksize_bits;
1090 sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
1091 GFS2_BASIC_BLOCK_SHIFT;
1092 sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
1093
1094 sdp->sd_tune.gt_logd_secs = sdp->sd_args.ar_commit;
1095 sdp->sd_tune.gt_quota_quantum = sdp->sd_args.ar_quota_quantum;
1096 if (sdp->sd_args.ar_statfs_quantum) {
1097 sdp->sd_tune.gt_statfs_slow = 0;
1098 sdp->sd_tune.gt_statfs_quantum = sdp->sd_args.ar_statfs_quantum;
1099 } else {
1100 sdp->sd_tune.gt_statfs_slow = 1;
1101 sdp->sd_tune.gt_statfs_quantum = 30;
1102 }
1103
1104 error = init_names(sdp, silent);
1105 if (error) {
1106 /* In this case, we haven't initialized sysfs, so we have to
1107 manually free the sdp. */
1108 free_percpu(sdp->sd_lkstats);
1109 kfree(sdp);
1110 sb->s_fs_info = NULL;
1111 return error;
1112 }
1113
1114 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s", sdp->sd_table_name);
1115
1116 error = gfs2_sys_fs_add(sdp);
1117 /*
1118 * If we hit an error here, gfs2_sys_fs_add will have called function
1119 * kobject_put which causes the sysfs usage count to go to zero, which
1120 * causes sysfs to call function gfs2_sbd_release, which frees sdp.
1121 * Subsequent error paths here will call gfs2_sys_fs_del, which also
1122 * kobject_put to free sdp.
1123 */
1124 if (error)
1125 return error;
1126
1127 gfs2_create_debugfs_file(sdp);
1128
1129 error = gfs2_lm_mount(sdp, silent);
1130 if (error)
1131 goto fail_debug;
1132
1133 error = init_locking(sdp, &mount_gh, DO);
1134 if (error)
1135 goto fail_lm;
1136
1137 error = init_sb(sdp, silent);
1138 if (error)
1139 goto fail_locking;
1140
1141 error = wait_on_journal(sdp);
1142 if (error)
1143 goto fail_sb;
1144
1145 /*
1146 * If user space has failed to join the cluster or some similar
1147 * failure has occurred, then the journal id will contain a
1148 * negative (error) number. This will then be returned to the
1149 * caller (of the mount syscall). We do this even for spectator
1150 * mounts (which just write a jid of 0 to indicate "ok" even though
1151 * the jid is unused in the spectator case)
1152 */
1153 if (sdp->sd_lockstruct.ls_jid < 0) {
1154 error = sdp->sd_lockstruct.ls_jid;
1155 sdp->sd_lockstruct.ls_jid = 0;
1156 goto fail_sb;
1157 }
1158
1159 if (sdp->sd_args.ar_spectator)
1160 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.s",
1161 sdp->sd_table_name);
1162 else
1163 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.%u",
1164 sdp->sd_table_name, sdp->sd_lockstruct.ls_jid);
1165
1166 error = init_inodes(sdp, DO);
1167 if (error)
1168 goto fail_sb;
1169
1170 error = init_per_node(sdp, DO);
1171 if (error)
1172 goto fail_inodes;
1173
1174 error = gfs2_statfs_init(sdp);
1175 if (error) {
1176 fs_err(sdp, "can't initialize statfs subsystem: %d\n", error);
1177 goto fail_per_node;
1178 }
1179
1180 if (!(sb->s_flags & MS_RDONLY)) {
1181 error = gfs2_make_fs_rw(sdp);
1182 if (error) {
1183 fs_err(sdp, "can't make FS RW: %d\n", error);
1184 goto fail_per_node;
1185 }
1186 }
1187
1188 gfs2_glock_dq_uninit(&mount_gh);
1189 gfs2_online_uevent(sdp);
1190 return 0;
1191
1192 fail_per_node:
1193 init_per_node(sdp, UNDO);
1194 fail_inodes:
1195 init_inodes(sdp, UNDO);
1196 fail_sb:
1197 if (sdp->sd_root_dir)
1198 dput(sdp->sd_root_dir);
1199 if (sdp->sd_master_dir)
1200 dput(sdp->sd_master_dir);
1201 if (sb->s_root)
1202 dput(sb->s_root);
1203 sb->s_root = NULL;
1204 fail_locking:
1205 init_locking(sdp, &mount_gh, UNDO);
1206 fail_lm:
1207 complete_all(&sdp->sd_journal_ready);
1208 gfs2_gl_hash_clear(sdp);
1209 gfs2_lm_unmount(sdp);
1210 fail_debug:
1211 gfs2_delete_debugfs_file(sdp);
1212 free_percpu(sdp->sd_lkstats);
1213 /* gfs2_sys_fs_del must be the last thing we do, since it causes
1214 * sysfs to call function gfs2_sbd_release, which frees sdp. */
1215 gfs2_sys_fs_del(sdp);
1216 sb->s_fs_info = NULL;
1217 return error;
1218 }
1219
set_gfs2_super(struct super_block * s,void * data)1220 static int set_gfs2_super(struct super_block *s, void *data)
1221 {
1222 s->s_bdev = data;
1223 s->s_dev = s->s_bdev->bd_dev;
1224
1225 /*
1226 * We set the bdi here to the queue backing, file systems can
1227 * overwrite this in ->fill_super()
1228 */
1229 s->s_bdi = &bdev_get_queue(s->s_bdev)->backing_dev_info;
1230 return 0;
1231 }
1232
test_gfs2_super(struct super_block * s,void * ptr)1233 static int test_gfs2_super(struct super_block *s, void *ptr)
1234 {
1235 struct block_device *bdev = ptr;
1236 return (bdev == s->s_bdev);
1237 }
1238
1239 /**
1240 * gfs2_mount - Get the GFS2 superblock
1241 * @fs_type: The GFS2 filesystem type
1242 * @flags: Mount flags
1243 * @dev_name: The name of the device
1244 * @data: The mount arguments
1245 *
1246 * Q. Why not use get_sb_bdev() ?
1247 * A. We need to select one of two root directories to mount, independent
1248 * of whether this is the initial, or subsequent, mount of this sb
1249 *
1250 * Returns: 0 or -ve on error
1251 */
1252
gfs2_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * data)1253 static struct dentry *gfs2_mount(struct file_system_type *fs_type, int flags,
1254 const char *dev_name, void *data)
1255 {
1256 struct block_device *bdev;
1257 struct super_block *s;
1258 fmode_t mode = FMODE_READ | FMODE_EXCL;
1259 int error;
1260 struct gfs2_args args;
1261 struct gfs2_sbd *sdp;
1262
1263 if (!(flags & MS_RDONLY))
1264 mode |= FMODE_WRITE;
1265
1266 bdev = blkdev_get_by_path(dev_name, mode, fs_type);
1267 if (IS_ERR(bdev))
1268 return ERR_CAST(bdev);
1269
1270 /*
1271 * once the super is inserted into the list by sget, s_umount
1272 * will protect the lockfs code from trying to start a snapshot
1273 * while we are mounting
1274 */
1275 mutex_lock(&bdev->bd_fsfreeze_mutex);
1276 if (bdev->bd_fsfreeze_count > 0) {
1277 mutex_unlock(&bdev->bd_fsfreeze_mutex);
1278 error = -EBUSY;
1279 goto error_bdev;
1280 }
1281 s = sget(fs_type, test_gfs2_super, set_gfs2_super, flags, bdev);
1282 mutex_unlock(&bdev->bd_fsfreeze_mutex);
1283 error = PTR_ERR(s);
1284 if (IS_ERR(s))
1285 goto error_bdev;
1286
1287 if (s->s_root) {
1288 /*
1289 * s_umount nests inside bd_mutex during
1290 * __invalidate_device(). blkdev_put() acquires
1291 * bd_mutex and can't be called under s_umount. Drop
1292 * s_umount temporarily. This is safe as we're
1293 * holding an active reference.
1294 */
1295 up_write(&s->s_umount);
1296 blkdev_put(bdev, mode);
1297 down_write(&s->s_umount);
1298 } else {
1299 /* s_mode must be set before deactivate_locked_super calls */
1300 s->s_mode = mode;
1301 }
1302
1303 memset(&args, 0, sizeof(args));
1304 args.ar_quota = GFS2_QUOTA_DEFAULT;
1305 args.ar_data = GFS2_DATA_DEFAULT;
1306 args.ar_commit = 30;
1307 args.ar_statfs_quantum = 30;
1308 args.ar_quota_quantum = 60;
1309 args.ar_errors = GFS2_ERRORS_DEFAULT;
1310
1311 error = gfs2_mount_args(&args, data);
1312 if (error) {
1313 pr_warn("can't parse mount arguments\n");
1314 goto error_super;
1315 }
1316
1317 if (s->s_root) {
1318 error = -EBUSY;
1319 if ((flags ^ s->s_flags) & MS_RDONLY)
1320 goto error_super;
1321 } else {
1322 char b[BDEVNAME_SIZE];
1323
1324 strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
1325 sb_set_blocksize(s, block_size(bdev));
1326 error = fill_super(s, &args, flags & MS_SILENT ? 1 : 0);
1327 if (error)
1328 goto error_super;
1329 s->s_flags |= MS_ACTIVE;
1330 bdev->bd_super = s;
1331 }
1332
1333 sdp = s->s_fs_info;
1334 if (args.ar_meta)
1335 return dget(sdp->sd_master_dir);
1336 else
1337 return dget(sdp->sd_root_dir);
1338
1339 error_super:
1340 deactivate_locked_super(s);
1341 return ERR_PTR(error);
1342 error_bdev:
1343 blkdev_put(bdev, mode);
1344 return ERR_PTR(error);
1345 }
1346
set_meta_super(struct super_block * s,void * ptr)1347 static int set_meta_super(struct super_block *s, void *ptr)
1348 {
1349 return -EINVAL;
1350 }
1351
gfs2_mount_meta(struct file_system_type * fs_type,int flags,const char * dev_name,void * data)1352 static struct dentry *gfs2_mount_meta(struct file_system_type *fs_type,
1353 int flags, const char *dev_name, void *data)
1354 {
1355 struct super_block *s;
1356 struct gfs2_sbd *sdp;
1357 struct path path;
1358 int error;
1359
1360 if (!dev_name || !*dev_name)
1361 return ERR_PTR(-EINVAL);
1362
1363 error = kern_path(dev_name, LOOKUP_FOLLOW, &path);
1364 if (error) {
1365 pr_warn("path_lookup on %s returned error %d\n",
1366 dev_name, error);
1367 return ERR_PTR(error);
1368 }
1369 s = sget(&gfs2_fs_type, test_gfs2_super, set_meta_super, flags,
1370 d_inode(path.dentry)->i_sb->s_bdev);
1371 path_put(&path);
1372 if (IS_ERR(s)) {
1373 pr_warn("gfs2 mount does not exist\n");
1374 return ERR_CAST(s);
1375 }
1376 if ((flags ^ s->s_flags) & MS_RDONLY) {
1377 deactivate_locked_super(s);
1378 return ERR_PTR(-EBUSY);
1379 }
1380 sdp = s->s_fs_info;
1381 return dget(sdp->sd_master_dir);
1382 }
1383
gfs2_kill_sb(struct super_block * sb)1384 static void gfs2_kill_sb(struct super_block *sb)
1385 {
1386 struct gfs2_sbd *sdp = sb->s_fs_info;
1387
1388 if (sdp == NULL) {
1389 kill_block_super(sb);
1390 return;
1391 }
1392
1393 gfs2_log_flush(sdp, NULL, SYNC_FLUSH);
1394 dput(sdp->sd_root_dir);
1395 dput(sdp->sd_master_dir);
1396 sdp->sd_root_dir = NULL;
1397 sdp->sd_master_dir = NULL;
1398 shrink_dcache_sb(sb);
1399 gfs2_delete_debugfs_file(sdp);
1400 free_percpu(sdp->sd_lkstats);
1401 kill_block_super(sb);
1402 }
1403
1404 struct file_system_type gfs2_fs_type = {
1405 .name = "gfs2",
1406 .fs_flags = FS_REQUIRES_DEV,
1407 .mount = gfs2_mount,
1408 .kill_sb = gfs2_kill_sb,
1409 .owner = THIS_MODULE,
1410 };
1411 MODULE_ALIAS_FS("gfs2");
1412
1413 struct file_system_type gfs2meta_fs_type = {
1414 .name = "gfs2meta",
1415 .fs_flags = FS_REQUIRES_DEV,
1416 .mount = gfs2_mount_meta,
1417 .owner = THIS_MODULE,
1418 };
1419 MODULE_ALIAS_FS("gfs2meta");
1420