Version:  2.0.40 2.2.26 2.4.37 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8

Linux/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 #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 
 53 static void gfs2_tune_init(struct gfs2_tune *gt)
 54 {
 55         spin_lock_init(&gt->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 
 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         sb->s_fs_info = sdp;
 75         sdp->sd_vfs = sb;
 76         sdp->sd_lkstats = alloc_percpu(struct gfs2_pcpu_lkstats);
 77         if (!sdp->sd_lkstats) {
 78                 kfree(sdp);
 79                 return NULL;
 80         }
 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 
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 format numbers match exactly, we're done.  */
164 
165         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
166             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
167                 return 0;
168 
169         fs_warn(sdp, "Unknown on-disk format, unable to mount\n");
170 
171         return -EINVAL;
172 }
173 
174 static void end_bio_io_page(struct bio *bio)
175 {
176         struct page *page = bio->bi_private;
177 
178         if (!bio->bi_error)
179                 SetPageUptodate(page);
180         else
181                 pr_warn("error %d reading superblock\n", bio->bi_error);
182         unlock_page(page);
183 }
184 
185 static void gfs2_sb_in(struct gfs2_sbd *sdp, const void *buf)
186 {
187         struct gfs2_sb_host *sb = &sdp->sd_sb;
188         struct super_block *s = sdp->sd_vfs;
189         const struct gfs2_sb *str = buf;
190 
191         sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
192         sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
193         sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
194         sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
195         sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
196         sb->sb_bsize = be32_to_cpu(str->sb_bsize);
197         sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
198         sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
199         sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
200         sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
201         sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
202 
203         memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
204         memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
205         memcpy(s->s_uuid, str->sb_uuid, 16);
206 }
207 
208 /**
209  * gfs2_read_super - Read the gfs2 super block from disk
210  * @sdp: The GFS2 super block
211  * @sector: The location of the super block
212  * @error: The error code to return
213  *
214  * This uses the bio functions to read the super block from disk
215  * because we want to be 100% sure that we never read cached data.
216  * A super block is read twice only during each GFS2 mount and is
217  * never written to by the filesystem. The first time its read no
218  * locks are held, and the only details which are looked at are those
219  * relating to the locking protocol. Once locking is up and working,
220  * the sb is read again under the lock to establish the location of
221  * the master directory (contains pointers to journals etc) and the
222  * root directory.
223  *
224  * Returns: 0 on success or error
225  */
226 
227 static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector, int silent)
228 {
229         struct super_block *sb = sdp->sd_vfs;
230         struct gfs2_sb *p;
231         struct page *page;
232         struct bio *bio;
233 
234         page = alloc_page(GFP_NOFS);
235         if (unlikely(!page))
236                 return -ENOMEM;
237 
238         ClearPageUptodate(page);
239         ClearPageDirty(page);
240         lock_page(page);
241 
242         bio = bio_alloc(GFP_NOFS, 1);
243         bio->bi_iter.bi_sector = sector * (sb->s_blocksize >> 9);
244         bio->bi_bdev = sb->s_bdev;
245         bio_add_page(bio, page, PAGE_SIZE, 0);
246 
247         bio->bi_end_io = end_bio_io_page;
248         bio->bi_private = page;
249         bio_set_op_attrs(bio, REQ_OP_READ, READ_SYNC | REQ_META);
250         submit_bio(bio);
251         wait_on_page_locked(page);
252         bio_put(bio);
253         if (!PageUptodate(page)) {
254                 __free_page(page);
255                 return -EIO;
256         }
257         p = kmap(page);
258         gfs2_sb_in(sdp, p);
259         kunmap(page);
260         __free_page(page);
261         return gfs2_check_sb(sdp, silent);
262 }
263 
264 /**
265  * gfs2_read_sb - Read super block
266  * @sdp: The GFS2 superblock
267  * @silent: Don't print message if mount fails
268  *
269  */
270 
271 static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
272 {
273         u32 hash_blocks, ind_blocks, leaf_blocks;
274         u32 tmp_blocks;
275         unsigned int x;
276         int error;
277 
278         error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
279         if (error) {
280                 if (!silent)
281                         fs_err(sdp, "can't read superblock\n");
282                 return error;
283         }
284 
285         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
286                                GFS2_BASIC_BLOCK_SHIFT;
287         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
288         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
289                           sizeof(struct gfs2_dinode)) / sizeof(u64);
290         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
291                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
292         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
293         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
294         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
295         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
296         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
297                                 sizeof(struct gfs2_meta_header)) /
298                                 sizeof(struct gfs2_quota_change);
299         sdp->sd_blocks_per_bitmap = (sdp->sd_sb.sb_bsize -
300                                      sizeof(struct gfs2_meta_header))
301                 * GFS2_NBBY; /* not the rgrp bitmap, subsequent bitmaps only */
302 
303         /* Compute maximum reservation required to add a entry to a directory */
304 
305         hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << GFS2_DIR_MAX_DEPTH),
306                              sdp->sd_jbsize);
307 
308         ind_blocks = 0;
309         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
310                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
311                 ind_blocks += tmp_blocks;
312         }
313 
314         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
315 
316         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
317 
318         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
319                                 sizeof(struct gfs2_dinode);
320         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
321         for (x = 2;; x++) {
322                 u64 space, d;
323                 u32 m;
324 
325                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
326                 d = space;
327                 m = do_div(d, sdp->sd_inptrs);
328 
329                 if (d != sdp->sd_heightsize[x - 1] || m)
330                         break;
331                 sdp->sd_heightsize[x] = space;
332         }
333         sdp->sd_max_height = x;
334         sdp->sd_heightsize[x] = ~0;
335         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
336 
337         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
338                                  sizeof(struct gfs2_dinode);
339         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
340         for (x = 2;; x++) {
341                 u64 space, d;
342                 u32 m;
343 
344                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
345                 d = space;
346                 m = do_div(d, sdp->sd_inptrs);
347 
348                 if (d != sdp->sd_jheightsize[x - 1] || m)
349                         break;
350                 sdp->sd_jheightsize[x] = space;
351         }
352         sdp->sd_max_jheight = x;
353         sdp->sd_jheightsize[x] = ~0;
354         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
355 
356         sdp->sd_max_dents_per_leaf = (sdp->sd_sb.sb_bsize -
357                                       sizeof(struct gfs2_leaf)) /
358                                      GFS2_MIN_DIRENT_SIZE;
359         return 0;
360 }
361 
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 
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 
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,
459                                   GFS2_BLKST_FREE /* ignore */);
460         if (IS_ERR(inode)) {
461                 fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
462                 return PTR_ERR(inode);
463         }
464         dentry = d_make_root(inode);
465         if (!dentry) {
466                 fs_err(sdp, "can't alloc %s dentry\n", name);
467                 return -ENOMEM;
468         }
469         *dptr = dentry;
470         return 0;
471 }
472 
473 static int init_sb(struct gfs2_sbd *sdp, int silent)
474 {
475         struct super_block *sb = sdp->sd_vfs;
476         struct gfs2_holder sb_gh;
477         u64 no_addr;
478         int ret;
479 
480         ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
481                                 LM_ST_SHARED, 0, &sb_gh);
482         if (ret) {
483                 fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
484                 return ret;
485         }
486 
487         ret = gfs2_read_sb(sdp, silent);
488         if (ret) {
489                 fs_err(sdp, "can't read superblock: %d\n", ret);
490                 goto out;
491         }
492 
493         /* Set up the buffer cache and SB for real */
494         if (sdp->sd_sb.sb_bsize < bdev_logical_block_size(sb->s_bdev)) {
495                 ret = -EINVAL;
496                 fs_err(sdp, "FS block size (%u) is too small for device "
497                        "block size (%u)\n",
498                        sdp->sd_sb.sb_bsize, bdev_logical_block_size(sb->s_bdev));
499                 goto out;
500         }
501         if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
502                 ret = -EINVAL;
503                 fs_err(sdp, "FS block size (%u) is too big for machine "
504                        "page size (%u)\n",
505                        sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
506                 goto out;
507         }
508         sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
509 
510         /* Get the root inode */
511         no_addr = sdp->sd_sb.sb_root_dir.no_addr;
512         ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
513         if (ret)
514                 goto out;
515 
516         /* Get the master inode */
517         no_addr = sdp->sd_sb.sb_master_dir.no_addr;
518         ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
519         if (ret) {
520                 dput(sdp->sd_root_dir);
521                 goto out;
522         }
523         sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
524 out:
525         gfs2_glock_dq_uninit(&sb_gh);
526         return ret;
527 }
528 
529 static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
530 {
531         char *message = "FIRSTMOUNT=Done";
532         char *envp[] = { message, NULL };
533 
534         fs_info(sdp, "first mount done, others may mount\n");
535 
536         if (sdp->sd_lockstruct.ls_ops->lm_first_done)
537                 sdp->sd_lockstruct.ls_ops->lm_first_done(sdp);
538 
539         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
540 }
541 
542 /**
543  * gfs2_jindex_hold - Grab a lock on the jindex
544  * @sdp: The GFS2 superblock
545  * @ji_gh: the holder for the jindex glock
546  *
547  * Returns: errno
548  */
549 
550 static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
551 {
552         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
553         struct qstr name;
554         char buf[20];
555         struct gfs2_jdesc *jd;
556         int error;
557 
558         name.name = buf;
559 
560         mutex_lock(&sdp->sd_jindex_mutex);
561 
562         for (;;) {
563                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
564                 if (error)
565                         break;
566 
567                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
568                 name.hash = gfs2_disk_hash(name.name, name.len);
569 
570                 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
571                 if (error == -ENOENT) {
572                         error = 0;
573                         break;
574                 }
575 
576                 gfs2_glock_dq_uninit(ji_gh);
577 
578                 if (error)
579                         break;
580 
581                 error = -ENOMEM;
582                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
583                 if (!jd)
584                         break;
585 
586                 INIT_LIST_HEAD(&jd->extent_list);
587                 INIT_LIST_HEAD(&jd->jd_revoke_list);
588 
589                 INIT_WORK(&jd->jd_work, gfs2_recover_func);
590                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
591                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
592                         if (!jd->jd_inode)
593                                 error = -ENOENT;
594                         else
595                                 error = PTR_ERR(jd->jd_inode);
596                         kfree(jd);
597                         break;
598                 }
599 
600                 spin_lock(&sdp->sd_jindex_spin);
601                 jd->jd_jid = sdp->sd_journals++;
602                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
603                 spin_unlock(&sdp->sd_jindex_spin);
604         }
605 
606         mutex_unlock(&sdp->sd_jindex_mutex);
607 
608         return error;
609 }
610 
611 /**
612  * check_journal_clean - Make sure a journal is clean for a spectator mount
613  * @sdp: The GFS2 superblock
614  * @jd: The journal descriptor
615  *
616  * Returns: 0 if the journal is clean or locked, else an error
617  */
618 static int check_journal_clean(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd)
619 {
620         int error;
621         struct gfs2_holder j_gh;
622         struct gfs2_log_header_host head;
623         struct gfs2_inode *ip;
624 
625         ip = GFS2_I(jd->jd_inode);
626         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_NOEXP |
627                                    GL_EXACT | GL_NOCACHE, &j_gh);
628         if (error) {
629                 fs_err(sdp, "Error locking journal for spectator mount.\n");
630                 return -EPERM;
631         }
632         error = gfs2_jdesc_check(jd);
633         if (error) {
634                 fs_err(sdp, "Error checking journal for spectator mount.\n");
635                 goto out_unlock;
636         }
637         error = gfs2_find_jhead(jd, &head);
638         if (error) {
639                 fs_err(sdp, "Error parsing journal for spectator mount.\n");
640                 goto out_unlock;
641         }
642         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
643                 error = -EPERM;
644                 fs_err(sdp, "jid=%u: Journal is dirty, so the first mounter "
645                        "must not be a spectator.\n", jd->jd_jid);
646         }
647 
648 out_unlock:
649         gfs2_glock_dq_uninit(&j_gh);
650         return error;
651 }
652 
653 static int init_journal(struct gfs2_sbd *sdp, int undo)
654 {
655         struct inode *master = d_inode(sdp->sd_master_dir);
656         struct gfs2_holder ji_gh;
657         struct gfs2_inode *ip;
658         int jindex = 1;
659         int error = 0;
660 
661         if (undo) {
662                 jindex = 0;
663                 goto fail_jinode_gh;
664         }
665 
666         sdp->sd_jindex = gfs2_lookup_simple(master, "jindex");
667         if (IS_ERR(sdp->sd_jindex)) {
668                 fs_err(sdp, "can't lookup journal index: %d\n", error);
669                 return PTR_ERR(sdp->sd_jindex);
670         }
671 
672         /* Load in the journal index special file */
673 
674         error = gfs2_jindex_hold(sdp, &ji_gh);
675         if (error) {
676                 fs_err(sdp, "can't read journal index: %d\n", error);
677                 goto fail;
678         }
679 
680         error = -EUSERS;
681         if (!gfs2_jindex_size(sdp)) {
682                 fs_err(sdp, "no journals!\n");
683                 goto fail_jindex;
684         }
685 
686         if (sdp->sd_args.ar_spectator) {
687                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
688                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
689                 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
690                 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
691         } else {
692                 if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
693                         fs_err(sdp, "can't mount journal #%u\n",
694                                sdp->sd_lockstruct.ls_jid);
695                         fs_err(sdp, "there are only %u journals (0 - %u)\n",
696                                gfs2_jindex_size(sdp),
697                                gfs2_jindex_size(sdp) - 1);
698                         goto fail_jindex;
699                 }
700                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);
701 
702                 error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
703                                           &gfs2_journal_glops,
704                                           LM_ST_EXCLUSIVE, LM_FLAG_NOEXP,
705                                           &sdp->sd_journal_gh);
706                 if (error) {
707                         fs_err(sdp, "can't acquire journal glock: %d\n", error);
708                         goto fail_jindex;
709                 }
710 
711                 ip = GFS2_I(sdp->sd_jdesc->jd_inode);
712                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
713                                            LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE,
714                                            &sdp->sd_jinode_gh);
715                 if (error) {
716                         fs_err(sdp, "can't acquire journal inode glock: %d\n",
717                                error);
718                         goto fail_journal_gh;
719                 }
720 
721                 error = gfs2_jdesc_check(sdp->sd_jdesc);
722                 if (error) {
723                         fs_err(sdp, "my journal (%u) is bad: %d\n",
724                                sdp->sd_jdesc->jd_jid, error);
725                         goto fail_jinode_gh;
726                 }
727                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
728                 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
729                 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
730 
731                 /* Map the extents for this journal's blocks */
732                 gfs2_map_journal_extents(sdp, sdp->sd_jdesc);
733         }
734         trace_gfs2_log_blocks(sdp, atomic_read(&sdp->sd_log_blks_free));
735 
736         if (sdp->sd_lockstruct.ls_first) {
737                 unsigned int x;
738                 for (x = 0; x < sdp->sd_journals; x++) {
739                         struct gfs2_jdesc *jd = gfs2_jdesc_find(sdp, x);
740 
741                         if (sdp->sd_args.ar_spectator) {
742                                 error = check_journal_clean(sdp, jd);
743                                 if (error)
744                                         goto fail_jinode_gh;
745                                 continue;
746                         }
747                         error = gfs2_recover_journal(jd, true);
748                         if (error) {
749                                 fs_err(sdp, "error recovering journal %u: %d\n",
750                                        x, error);
751                                 goto fail_jinode_gh;
752                         }
753                 }
754 
755                 gfs2_others_may_mount(sdp);
756         } else if (!sdp->sd_args.ar_spectator) {
757                 error = gfs2_recover_journal(sdp->sd_jdesc, true);
758                 if (error) {
759                         fs_err(sdp, "error recovering my journal: %d\n", error);
760                         goto fail_jinode_gh;
761                 }
762         }
763 
764         sdp->sd_log_idle = 1;
765         set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
766         gfs2_glock_dq_uninit(&ji_gh);
767         jindex = 0;
768         INIT_WORK(&sdp->sd_freeze_work, gfs2_freeze_func);
769         return 0;
770 
771 fail_jinode_gh:
772         if (!sdp->sd_args.ar_spectator)
773                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
774 fail_journal_gh:
775         if (!sdp->sd_args.ar_spectator)
776                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
777 fail_jindex:
778         gfs2_jindex_free(sdp);
779         if (jindex)
780                 gfs2_glock_dq_uninit(&ji_gh);
781 fail:
782         iput(sdp->sd_jindex);
783         return error;
784 }
785 
786 static struct lock_class_key gfs2_quota_imutex_key;
787 
788 static int init_inodes(struct gfs2_sbd *sdp, int undo)
789 {
790         int error = 0;
791         struct inode *master = d_inode(sdp->sd_master_dir);
792 
793         if (undo)
794                 goto fail_qinode;
795 
796         error = init_journal(sdp, undo);
797         complete_all(&sdp->sd_journal_ready);
798         if (error)
799                 goto fail;
800 
801         /* Read in the master statfs inode */
802         sdp->sd_statfs_inode = gfs2_lookup_simple(master, "statfs");
803         if (IS_ERR(sdp->sd_statfs_inode)) {
804                 error = PTR_ERR(sdp->sd_statfs_inode);
805                 fs_err(sdp, "can't read in statfs inode: %d\n", error);
806                 goto fail_journal;
807         }
808 
809         /* Read in the resource index inode */
810         sdp->sd_rindex = gfs2_lookup_simple(master, "rindex");
811         if (IS_ERR(sdp->sd_rindex)) {
812                 error = PTR_ERR(sdp->sd_rindex);
813                 fs_err(sdp, "can't get resource index inode: %d\n", error);
814                 goto fail_statfs;
815         }
816         sdp->sd_rindex_uptodate = 0;
817 
818         /* Read in the quota inode */
819         sdp->sd_quota_inode = gfs2_lookup_simple(master, "quota");
820         if (IS_ERR(sdp->sd_quota_inode)) {
821                 error = PTR_ERR(sdp->sd_quota_inode);
822                 fs_err(sdp, "can't get quota file inode: %d\n", error);
823                 goto fail_rindex;
824         }
825         /*
826          * i_mutex on quota files is special. Since this inode is hidden system
827          * file, we are safe to define locking ourselves.
828          */
829         lockdep_set_class(&sdp->sd_quota_inode->i_rwsem,
830                           &gfs2_quota_imutex_key);
831 
832         error = gfs2_rindex_update(sdp);
833         if (error)
834                 goto fail_qinode;
835 
836         return 0;
837 
838 fail_qinode:
839         iput(sdp->sd_quota_inode);
840 fail_rindex:
841         gfs2_clear_rgrpd(sdp);
842         iput(sdp->sd_rindex);
843 fail_statfs:
844         iput(sdp->sd_statfs_inode);
845 fail_journal:
846         init_journal(sdp, UNDO);
847 fail:
848         return error;
849 }
850 
851 static int init_per_node(struct gfs2_sbd *sdp, int undo)
852 {
853         struct inode *pn = NULL;
854         char buf[30];
855         int error = 0;
856         struct gfs2_inode *ip;
857         struct inode *master = d_inode(sdp->sd_master_dir);
858 
859         if (sdp->sd_args.ar_spectator)
860                 return 0;
861 
862         if (undo)
863                 goto fail_qc_gh;
864 
865         pn = gfs2_lookup_simple(master, "per_node");
866         if (IS_ERR(pn)) {
867                 error = PTR_ERR(pn);
868                 fs_err(sdp, "can't find per_node directory: %d\n", error);
869                 return error;
870         }
871 
872         sprintf(buf, "statfs_change%u", sdp->sd_jdesc->jd_jid);
873         sdp->sd_sc_inode = gfs2_lookup_simple(pn, buf);
874         if (IS_ERR(sdp->sd_sc_inode)) {
875                 error = PTR_ERR(sdp->sd_sc_inode);
876                 fs_err(sdp, "can't find local \"sc\" file: %d\n", error);
877                 goto fail;
878         }
879 
880         sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
881         sdp->sd_qc_inode = gfs2_lookup_simple(pn, buf);
882         if (IS_ERR(sdp->sd_qc_inode)) {
883                 error = PTR_ERR(sdp->sd_qc_inode);
884                 fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
885                 goto fail_ut_i;
886         }
887 
888         iput(pn);
889         pn = NULL;
890 
891         ip = GFS2_I(sdp->sd_sc_inode);
892         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
893                                    &sdp->sd_sc_gh);
894         if (error) {
895                 fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
896                 goto fail_qc_i;
897         }
898 
899         ip = GFS2_I(sdp->sd_qc_inode);
900         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
901                                    &sdp->sd_qc_gh);
902         if (error) {
903                 fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
904                 goto fail_ut_gh;
905         }
906 
907         return 0;
908 
909 fail_qc_gh:
910         gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
911 fail_ut_gh:
912         gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
913 fail_qc_i:
914         iput(sdp->sd_qc_inode);
915 fail_ut_i:
916         iput(sdp->sd_sc_inode);
917 fail:
918         iput(pn);
919         return error;
920 }
921 
922 static const match_table_t nolock_tokens = {
923         { Opt_jid, "jid=%d\n", },
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 
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 
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 
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 
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 
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 
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 
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 
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                 snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev);
1323                 sb_set_blocksize(s, block_size(bdev));
1324                 error = fill_super(s, &args, flags & MS_SILENT ? 1 : 0);
1325                 if (error)
1326                         goto error_super;
1327                 s->s_flags |= MS_ACTIVE;
1328                 bdev->bd_super = s;
1329         }
1330 
1331         sdp = s->s_fs_info;
1332         if (args.ar_meta)
1333                 return dget(sdp->sd_master_dir);
1334         else
1335                 return dget(sdp->sd_root_dir);
1336 
1337 error_super:
1338         deactivate_locked_super(s);
1339         return ERR_PTR(error);
1340 error_bdev:
1341         blkdev_put(bdev, mode);
1342         return ERR_PTR(error);
1343 }
1344 
1345 static int set_meta_super(struct super_block *s, void *ptr)
1346 {
1347         return -EINVAL;
1348 }
1349 
1350 static struct dentry *gfs2_mount_meta(struct file_system_type *fs_type,
1351                         int flags, const char *dev_name, void *data)
1352 {
1353         struct super_block *s;
1354         struct gfs2_sbd *sdp;
1355         struct path path;
1356         int error;
1357 
1358         error = kern_path(dev_name, LOOKUP_FOLLOW, &path);
1359         if (error) {
1360                 pr_warn("path_lookup on %s returned error %d\n",
1361                         dev_name, error);
1362                 return ERR_PTR(error);
1363         }
1364         s = sget(&gfs2_fs_type, test_gfs2_super, set_meta_super, flags,
1365                  path.dentry->d_sb->s_bdev);
1366         path_put(&path);
1367         if (IS_ERR(s)) {
1368                 pr_warn("gfs2 mount does not exist\n");
1369                 return ERR_CAST(s);
1370         }
1371         if ((flags ^ s->s_flags) & MS_RDONLY) {
1372                 deactivate_locked_super(s);
1373                 return ERR_PTR(-EBUSY);
1374         }
1375         sdp = s->s_fs_info;
1376         return dget(sdp->sd_master_dir);
1377 }
1378 
1379 static void gfs2_kill_sb(struct super_block *sb)
1380 {
1381         struct gfs2_sbd *sdp = sb->s_fs_info;
1382 
1383         if (sdp == NULL) {
1384                 kill_block_super(sb);
1385                 return;
1386         }
1387 
1388         gfs2_log_flush(sdp, NULL, SYNC_FLUSH);
1389         dput(sdp->sd_root_dir);
1390         dput(sdp->sd_master_dir);
1391         sdp->sd_root_dir = NULL;
1392         sdp->sd_master_dir = NULL;
1393         shrink_dcache_sb(sb);
1394         gfs2_delete_debugfs_file(sdp);
1395         free_percpu(sdp->sd_lkstats);
1396         kill_block_super(sb);
1397 }
1398 
1399 struct file_system_type gfs2_fs_type = {
1400         .name = "gfs2",
1401         .fs_flags = FS_REQUIRES_DEV,
1402         .mount = gfs2_mount,
1403         .kill_sb = gfs2_kill_sb,
1404         .owner = THIS_MODULE,
1405 };
1406 MODULE_ALIAS_FS("gfs2");
1407 
1408 struct file_system_type gfs2meta_fs_type = {
1409         .name = "gfs2meta",
1410         .fs_flags = FS_REQUIRES_DEV,
1411         .mount = gfs2_mount_meta,
1412         .owner = THIS_MODULE,
1413 };
1414 MODULE_ALIAS_FS("gfs2meta");
1415 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us