blob: 1d1b6e1251593ae16753f30bca38e351c0a9d163 [file] [log] [blame]
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001/*
2 * super.c - NILFS module and super block management.
3 *
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
21 */
22/*
23 * linux/fs/ext2/super.c
24 *
25 * Copyright (C) 1992, 1993, 1994, 1995
26 * Remy Card (card@masi.ibp.fr)
27 * Laboratoire MASI - Institut Blaise Pascal
28 * Universite Pierre et Marie Curie (Paris VI)
29 *
30 * from
31 *
32 * linux/fs/minix/inode.c
33 *
34 * Copyright (C) 1991, 1992 Linus Torvalds
35 *
36 * Big-endian to little-endian byte-swapping/bitmaps by
37 * David S. Miller (davem@caip.rutgers.edu), 1995
38 */
39
40#include <linux/module.h>
41#include <linux/string.h>
42#include <linux/slab.h>
43#include <linux/init.h>
44#include <linux/blkdev.h>
45#include <linux/parser.h>
46#include <linux/random.h>
47#include <linux/crc32.h>
48#include <linux/smp_lock.h>
49#include <linux/vfs.h>
50#include <linux/writeback.h>
51#include <linux/kobject.h>
52#include <linux/exportfs.h>
53#include "nilfs.h"
54#include "mdt.h"
55#include "alloc.h"
56#include "page.h"
57#include "cpfile.h"
58#include "ifile.h"
59#include "dat.h"
60#include "segment.h"
61#include "segbuf.h"
62
63MODULE_AUTHOR("NTT Corp.");
64MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
65 "(NILFS)");
Ryusuke Konishi783f6182009-04-06 19:01:35 -070066MODULE_LICENSE("GPL");
67
Christoph Hellwig8c85e122009-04-28 18:00:26 +020068static void nilfs_write_super(struct super_block *sb);
Ryusuke Konishi783f6182009-04-06 19:01:35 -070069static int nilfs_remount(struct super_block *sb, int *flags, char *data);
Ryusuke Konishi783f6182009-04-06 19:01:35 -070070
71/**
72 * nilfs_error() - report failure condition on a filesystem
73 *
74 * nilfs_error() sets an ERROR_FS flag on the superblock as well as
75 * reporting an error message. It should be called when NILFS detects
76 * incoherences or defects of meta data on disk. As for sustainable
77 * errors such as a single-shot I/O error, nilfs_warning() or the printk()
78 * function should be used instead.
79 *
80 * The segment constructor must not call this function because it can
81 * kill itself.
82 */
83void nilfs_error(struct super_block *sb, const char *function,
84 const char *fmt, ...)
85{
86 struct nilfs_sb_info *sbi = NILFS_SB(sb);
87 va_list args;
88
89 va_start(args, fmt);
90 printk(KERN_CRIT "NILFS error (device %s): %s: ", sb->s_id, function);
91 vprintk(fmt, args);
92 printk("\n");
93 va_end(args);
94
95 if (!(sb->s_flags & MS_RDONLY)) {
96 struct the_nilfs *nilfs = sbi->s_nilfs;
97
98 if (!nilfs_test_opt(sbi, ERRORS_CONT))
99 nilfs_detach_segment_constructor(sbi);
100
101 down_write(&nilfs->ns_sem);
102 if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
103 nilfs->ns_mount_state |= NILFS_ERROR_FS;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700104 nilfs->ns_sbp[0]->s_state |=
105 cpu_to_le16(NILFS_ERROR_FS);
106 nilfs_commit_super(sbi, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700107 }
108 up_write(&nilfs->ns_sem);
109
110 if (nilfs_test_opt(sbi, ERRORS_RO)) {
111 printk(KERN_CRIT "Remounting filesystem read-only\n");
112 sb->s_flags |= MS_RDONLY;
113 }
114 }
115
116 if (nilfs_test_opt(sbi, ERRORS_PANIC))
117 panic("NILFS (device %s): panic forced after error\n",
118 sb->s_id);
119}
120
121void nilfs_warning(struct super_block *sb, const char *function,
122 const char *fmt, ...)
123{
124 va_list args;
125
126 va_start(args, fmt);
127 printk(KERN_WARNING "NILFS warning (device %s): %s: ",
128 sb->s_id, function);
129 vprintk(fmt, args);
130 printk("\n");
131 va_end(args);
132}
133
134static struct kmem_cache *nilfs_inode_cachep;
135
136struct inode *nilfs_alloc_inode(struct super_block *sb)
137{
138 struct nilfs_inode_info *ii;
139
140 ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS);
141 if (!ii)
142 return NULL;
143 ii->i_bh = NULL;
144 ii->i_state = 0;
145 ii->vfs_inode.i_version = 1;
146 nilfs_btnode_cache_init(&ii->i_btnode_cache);
147 return &ii->vfs_inode;
148}
149
150void nilfs_destroy_inode(struct inode *inode)
151{
152 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
153}
154
155static void init_once(void *obj)
156{
157 struct nilfs_inode_info *ii = obj;
158
159 INIT_LIST_HEAD(&ii->i_dirty);
160#ifdef CONFIG_NILFS_XATTR
161 init_rwsem(&ii->xattr_sem);
162#endif
163 nilfs_btnode_cache_init_once(&ii->i_btnode_cache);
164 ii->i_bmap = (struct nilfs_bmap *)&ii->i_bmap_union;
165 inode_init_once(&ii->vfs_inode);
166}
167
168static int nilfs_init_inode_cache(void)
169{
170 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
171 sizeof(struct nilfs_inode_info),
172 0, SLAB_RECLAIM_ACCOUNT,
173 init_once);
174
175 return (nilfs_inode_cachep == NULL) ? -ENOMEM : 0;
176}
177
178static inline void nilfs_destroy_inode_cache(void)
179{
180 kmem_cache_destroy(nilfs_inode_cachep);
181}
182
183static void nilfs_clear_inode(struct inode *inode)
184{
185 struct nilfs_inode_info *ii = NILFS_I(inode);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700186
187#ifdef CONFIG_NILFS_POSIX_ACL
188 if (ii->i_acl && ii->i_acl != NILFS_ACL_NOT_CACHED) {
189 posix_acl_release(ii->i_acl);
190 ii->i_acl = NILFS_ACL_NOT_CACHED;
191 }
192 if (ii->i_default_acl && ii->i_default_acl != NILFS_ACL_NOT_CACHED) {
193 posix_acl_release(ii->i_default_acl);
194 ii->i_default_acl = NILFS_ACL_NOT_CACHED;
195 }
196#endif
197 /*
198 * Free resources allocated in nilfs_read_inode(), here.
199 */
Ryusuke Konishia2e7d2d2009-04-06 19:01:44 -0700200 BUG_ON(!list_empty(&ii->i_dirty));
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700201 brelse(ii->i_bh);
202 ii->i_bh = NULL;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700203
204 if (test_bit(NILFS_I_BMAP, &ii->i_state))
205 nilfs_bmap_clear(ii->i_bmap);
206
207 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700208}
209
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700210static int nilfs_sync_super(struct nilfs_sb_info *sbi, int dupsb)
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700211{
212 struct the_nilfs *nilfs = sbi->s_nilfs;
213 int err;
214 int barrier_done = 0;
215
216 if (nilfs_test_opt(sbi, BARRIER)) {
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700217 set_buffer_ordered(nilfs->ns_sbh[0]);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700218 barrier_done = 1;
219 }
220 retry:
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700221 set_buffer_dirty(nilfs->ns_sbh[0]);
222 err = sync_dirty_buffer(nilfs->ns_sbh[0]);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700223 if (err == -EOPNOTSUPP && barrier_done) {
224 nilfs_warning(sbi->s_super, __func__,
225 "barrier-based sync failed. "
226 "disabling barriers\n");
227 nilfs_clear_opt(sbi, BARRIER);
228 barrier_done = 0;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700229 clear_buffer_ordered(nilfs->ns_sbh[0]);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700230 goto retry;
231 }
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700232 if (unlikely(err)) {
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700233 printk(KERN_ERR
234 "NILFS: unable to write superblock (err=%d)\n", err);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700235 if (err == -EIO && nilfs->ns_sbh[1]) {
236 nilfs_fall_back_super_block(nilfs);
237 goto retry;
238 }
239 } else {
240 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
241
242 /*
243 * The latest segment becomes trailable from the position
244 * written in superblock.
245 */
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700246 clear_nilfs_discontinued(nilfs);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700247
248 /* update GC protection for recent segments */
249 if (nilfs->ns_sbh[1]) {
250 sbp = NULL;
251 if (dupsb) {
252 set_buffer_dirty(nilfs->ns_sbh[1]);
253 if (!sync_dirty_buffer(nilfs->ns_sbh[1]))
254 sbp = nilfs->ns_sbp[1];
255 }
256 }
257 if (sbp) {
258 spin_lock(&nilfs->ns_last_segment_lock);
259 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
260 spin_unlock(&nilfs->ns_last_segment_lock);
261 }
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700262 }
263
264 return err;
265}
266
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700267int nilfs_commit_super(struct nilfs_sb_info *sbi, int dupsb)
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700268{
269 struct the_nilfs *nilfs = sbi->s_nilfs;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700270 struct nilfs_super_block **sbp = nilfs->ns_sbp;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700271 sector_t nfreeblocks;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700272 time_t t;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700273 int err;
274
275 /* nilfs->sem must be locked by the caller. */
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700276 if (sbp[0]->s_magic != NILFS_SUPER_MAGIC) {
277 if (sbp[1] && sbp[1]->s_magic == NILFS_SUPER_MAGIC)
278 nilfs_swap_super_block(nilfs);
279 else {
280 printk(KERN_CRIT "NILFS: superblock broke on dev %s\n",
281 sbi->s_super->s_id);
282 return -EIO;
283 }
284 }
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700285 err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
286 if (unlikely(err)) {
287 printk(KERN_ERR "NILFS: failed to count free blocks\n");
288 return err;
289 }
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700290 spin_lock(&nilfs->ns_last_segment_lock);
291 sbp[0]->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
292 sbp[0]->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
293 sbp[0]->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
294 spin_unlock(&nilfs->ns_last_segment_lock);
295
296 t = get_seconds();
297 nilfs->ns_sbwtime[0] = t;
298 sbp[0]->s_free_blocks_count = cpu_to_le64(nfreeblocks);
299 sbp[0]->s_wtime = cpu_to_le64(t);
300 sbp[0]->s_sum = 0;
301 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
302 (unsigned char *)sbp[0],
303 nilfs->ns_sbsize));
304 if (dupsb && sbp[1]) {
305 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
306 nilfs->ns_sbwtime[1] = t;
307 }
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700308 sbi->s_super->s_dirt = 0;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700309 return nilfs_sync_super(sbi, dupsb);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700310}
311
312static void nilfs_put_super(struct super_block *sb)
313{
314 struct nilfs_sb_info *sbi = NILFS_SB(sb);
315 struct the_nilfs *nilfs = sbi->s_nilfs;
316
Christoph Hellwig6cfd0142009-05-05 15:40:36 +0200317 lock_kernel();
318
Christoph Hellwig8c85e122009-04-28 18:00:26 +0200319 if (sb->s_dirt)
320 nilfs_write_super(sb);
321
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700322 nilfs_detach_segment_constructor(sbi);
323
324 if (!(sb->s_flags & MS_RDONLY)) {
325 down_write(&nilfs->ns_sem);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700326 nilfs->ns_sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state);
327 nilfs_commit_super(sbi, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700328 up_write(&nilfs->ns_sem);
329 }
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900330 down_write(&nilfs->ns_sem);
331 if (nilfs->ns_current == sbi)
332 nilfs->ns_current = NULL;
333 up_write(&nilfs->ns_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700334
335 nilfs_detach_checkpoint(sbi);
336 put_nilfs(sbi->s_nilfs);
337 sbi->s_super = NULL;
338 sb->s_fs_info = NULL;
Ryusuke Konishi6dd47402009-06-08 01:39:31 +0900339 nilfs_put_sbinfo(sbi);
Christoph Hellwig6cfd0142009-05-05 15:40:36 +0200340
341 unlock_kernel();
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700342}
343
344/**
345 * nilfs_write_super - write super block(s) of NILFS
346 * @sb: super_block
347 *
348 * nilfs_write_super() gets a fs-dependent lock, writes super block(s), and
349 * clears s_dirt. This function is called in the section protected by
350 * lock_super().
351 *
352 * The s_dirt flag is managed by each filesystem and we protect it by ns_sem
353 * of the struct the_nilfs. Lock order must be as follows:
354 *
355 * 1. lock_super()
356 * 2. down_write(&nilfs->ns_sem)
357 *
358 * Inside NILFS, locking ns_sem is enough to protect s_dirt and the buffer
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700359 * of the super block (nilfs->ns_sbp[]).
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700360 *
361 * In most cases, VFS functions call lock_super() before calling these
362 * methods. So we must be careful not to bring on deadlocks when using
363 * lock_super(); see generic_shutdown_super(), write_super(), and so on.
364 *
365 * Note that order of lock_kernel() and lock_super() depends on contexts
366 * of VFS. We should also note that lock_kernel() can be used in its
367 * protective section and only the outermost one has an effect.
368 */
369static void nilfs_write_super(struct super_block *sb)
370{
371 struct nilfs_sb_info *sbi = NILFS_SB(sb);
372 struct the_nilfs *nilfs = sbi->s_nilfs;
373
374 down_write(&nilfs->ns_sem);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700375 if (!(sb->s_flags & MS_RDONLY)) {
376 struct nilfs_super_block **sbp = nilfs->ns_sbp;
377 u64 t = get_seconds();
378 int dupsb;
379
380 if (!nilfs_discontinued(nilfs) && t >= nilfs->ns_sbwtime[0] &&
381 t < nilfs->ns_sbwtime[0] + NILFS_SB_FREQ) {
382 up_write(&nilfs->ns_sem);
383 return;
384 }
385 dupsb = sbp[1] && t > nilfs->ns_sbwtime[1] + NILFS_ALTSB_FREQ;
386 nilfs_commit_super(sbi, dupsb);
387 }
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700388 sb->s_dirt = 0;
389 up_write(&nilfs->ns_sem);
390}
391
392static int nilfs_sync_fs(struct super_block *sb, int wait)
393{
394 int err = 0;
395
Christoph Hellwigd731e062009-06-08 10:08:36 +0200396 nilfs_write_super(sb);
397
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700398 /* This function is called when super block should be written back */
399 if (wait)
400 err = nilfs_construct_segment(sb);
401 return err;
402}
403
404int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno)
405{
406 struct the_nilfs *nilfs = sbi->s_nilfs;
407 struct nilfs_checkpoint *raw_cp;
408 struct buffer_head *bh_cp;
409 int err;
410
411 down_write(&nilfs->ns_sem);
412 list_add(&sbi->s_list, &nilfs->ns_supers);
413 up_write(&nilfs->ns_sem);
414
415 sbi->s_ifile = nilfs_mdt_new(
416 nilfs, sbi->s_super, NILFS_IFILE_INO, NILFS_IFILE_GFP);
417 if (!sbi->s_ifile)
418 return -ENOMEM;
419
420 err = nilfs_palloc_init_blockgroup(sbi->s_ifile, nilfs->ns_inode_size);
421 if (unlikely(err))
422 goto failed;
423
424 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
425 &bh_cp);
426 if (unlikely(err)) {
427 if (err == -ENOENT || err == -EINVAL) {
428 printk(KERN_ERR
429 "NILFS: Invalid checkpoint "
430 "(checkpoint number=%llu)\n",
431 (unsigned long long)cno);
432 err = -EINVAL;
433 }
434 goto failed;
435 }
436 err = nilfs_read_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode);
437 if (unlikely(err))
438 goto failed_bh;
439 atomic_set(&sbi->s_inodes_count, le64_to_cpu(raw_cp->cp_inodes_count));
440 atomic_set(&sbi->s_blocks_count, le64_to_cpu(raw_cp->cp_blocks_count));
441
442 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
443 return 0;
444
445 failed_bh:
446 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
447 failed:
448 nilfs_mdt_destroy(sbi->s_ifile);
449 sbi->s_ifile = NULL;
450
451 down_write(&nilfs->ns_sem);
452 list_del_init(&sbi->s_list);
453 up_write(&nilfs->ns_sem);
454
455 return err;
456}
457
458void nilfs_detach_checkpoint(struct nilfs_sb_info *sbi)
459{
460 struct the_nilfs *nilfs = sbi->s_nilfs;
461
462 nilfs_mdt_clear(sbi->s_ifile);
463 nilfs_mdt_destroy(sbi->s_ifile);
464 sbi->s_ifile = NULL;
465 down_write(&nilfs->ns_sem);
466 list_del_init(&sbi->s_list);
467 up_write(&nilfs->ns_sem);
468}
469
470static int nilfs_mark_recovery_complete(struct nilfs_sb_info *sbi)
471{
472 struct the_nilfs *nilfs = sbi->s_nilfs;
473 int err = 0;
474
475 down_write(&nilfs->ns_sem);
476 if (!(nilfs->ns_mount_state & NILFS_VALID_FS)) {
477 nilfs->ns_mount_state |= NILFS_VALID_FS;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700478 err = nilfs_commit_super(sbi, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700479 if (likely(!err))
480 printk(KERN_INFO "NILFS: recovery complete.\n");
481 }
482 up_write(&nilfs->ns_sem);
483 return err;
484}
485
486static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
487{
488 struct super_block *sb = dentry->d_sb;
489 struct nilfs_sb_info *sbi = NILFS_SB(sb);
Ryusuke Konishic306af22009-03-26 10:16:57 +0900490 struct the_nilfs *nilfs = sbi->s_nilfs;
491 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700492 unsigned long long blocks;
493 unsigned long overhead;
494 unsigned long nrsvblocks;
495 sector_t nfreeblocks;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700496 int err;
497
498 /*
499 * Compute all of the segment blocks
500 *
501 * The blocks before first segment and after last segment
502 * are excluded.
503 */
504 blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments
505 - nilfs->ns_first_data_block;
506 nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment;
507
508 /*
509 * Compute the overhead
510 *
511 * When distributing meta data blocks outside semgent structure,
512 * We must count them as the overhead.
513 */
514 overhead = 0;
515
516 err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
517 if (unlikely(err))
518 return err;
519
520 buf->f_type = NILFS_SUPER_MAGIC;
521 buf->f_bsize = sb->s_blocksize;
522 buf->f_blocks = blocks - overhead;
523 buf->f_bfree = nfreeblocks;
524 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
525 (buf->f_bfree - nrsvblocks) : 0;
526 buf->f_files = atomic_read(&sbi->s_inodes_count);
527 buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */
528 buf->f_namelen = NILFS_NAME_LEN;
Ryusuke Konishic306af22009-03-26 10:16:57 +0900529 buf->f_fsid.val[0] = (u32)id;
530 buf->f_fsid.val[1] = (u32)(id >> 32);
531
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700532 return 0;
533}
534
535static struct super_operations nilfs_sops = {
536 .alloc_inode = nilfs_alloc_inode,
537 .destroy_inode = nilfs_destroy_inode,
538 .dirty_inode = nilfs_dirty_inode,
539 /* .write_inode = nilfs_write_inode, */
540 /* .put_inode = nilfs_put_inode, */
541 /* .drop_inode = nilfs_drop_inode, */
542 .delete_inode = nilfs_delete_inode,
543 .put_super = nilfs_put_super,
544 .write_super = nilfs_write_super,
545 .sync_fs = nilfs_sync_fs,
546 /* .write_super_lockfs */
547 /* .unlockfs */
548 .statfs = nilfs_statfs,
549 .remount_fs = nilfs_remount,
550 .clear_inode = nilfs_clear_inode,
551 /* .umount_begin */
552 /* .show_options */
553};
554
555static struct inode *
556nilfs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation)
557{
558 struct inode *inode;
559
560 if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO &&
561 ino != NILFS_SKETCH_INO)
562 return ERR_PTR(-ESTALE);
563
564 inode = nilfs_iget(sb, ino);
565 if (IS_ERR(inode))
566 return ERR_CAST(inode);
567 if (generation && inode->i_generation != generation) {
568 iput(inode);
569 return ERR_PTR(-ESTALE);
570 }
571
572 return inode;
573}
574
575static struct dentry *
576nilfs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len,
577 int fh_type)
578{
579 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
580 nilfs_nfs_get_inode);
581}
582
583static struct dentry *
584nilfs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len,
585 int fh_type)
586{
587 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
588 nilfs_nfs_get_inode);
589}
590
591static struct export_operations nilfs_export_ops = {
592 .fh_to_dentry = nilfs_fh_to_dentry,
593 .fh_to_parent = nilfs_fh_to_parent,
594 .get_parent = nilfs_get_parent,
595};
596
597enum {
598 Opt_err_cont, Opt_err_panic, Opt_err_ro,
599 Opt_barrier, Opt_snapshot, Opt_order,
600 Opt_err,
601};
602
603static match_table_t tokens = {
604 {Opt_err_cont, "errors=continue"},
605 {Opt_err_panic, "errors=panic"},
606 {Opt_err_ro, "errors=remount-ro"},
607 {Opt_barrier, "barrier=%s"},
608 {Opt_snapshot, "cp=%u"},
609 {Opt_order, "order=%s"},
610 {Opt_err, NULL}
611};
612
613static int match_bool(substring_t *s, int *result)
614{
615 int len = s->to - s->from;
616
617 if (strncmp(s->from, "on", len) == 0)
618 *result = 1;
619 else if (strncmp(s->from, "off", len) == 0)
620 *result = 0;
621 else
622 return 1;
623 return 0;
624}
625
626static int parse_options(char *options, struct super_block *sb)
627{
628 struct nilfs_sb_info *sbi = NILFS_SB(sb);
629 char *p;
630 substring_t args[MAX_OPT_ARGS];
631 int option;
632
633 if (!options)
634 return 1;
635
636 while ((p = strsep(&options, ",")) != NULL) {
637 int token;
638 if (!*p)
639 continue;
640
641 token = match_token(p, tokens, args);
642 switch (token) {
643 case Opt_barrier:
644 if (match_bool(&args[0], &option))
645 return 0;
646 if (option)
647 nilfs_set_opt(sbi, BARRIER);
648 else
649 nilfs_clear_opt(sbi, BARRIER);
650 break;
651 case Opt_order:
652 if (strcmp(args[0].from, "relaxed") == 0)
653 /* Ordered data semantics */
654 nilfs_clear_opt(sbi, STRICT_ORDER);
655 else if (strcmp(args[0].from, "strict") == 0)
656 /* Strict in-order semantics */
657 nilfs_set_opt(sbi, STRICT_ORDER);
658 else
659 return 0;
660 break;
661 case Opt_err_panic:
662 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_PANIC);
663 break;
664 case Opt_err_ro:
665 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_RO);
666 break;
667 case Opt_err_cont:
668 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_CONT);
669 break;
670 case Opt_snapshot:
671 if (match_int(&args[0], &option) || option <= 0)
672 return 0;
673 if (!(sb->s_flags & MS_RDONLY))
674 return 0;
675 sbi->s_snapshot_cno = option;
676 nilfs_set_opt(sbi, SNAPSHOT);
677 break;
678 default:
679 printk(KERN_ERR
680 "NILFS: Unrecognized mount option \"%s\"\n", p);
681 return 0;
682 }
683 }
684 return 1;
685}
686
687static inline void
688nilfs_set_default_options(struct nilfs_sb_info *sbi,
689 struct nilfs_super_block *sbp)
690{
691 sbi->s_mount_opt =
692 NILFS_MOUNT_ERRORS_CONT | NILFS_MOUNT_BARRIER;
693}
694
695static int nilfs_setup_super(struct nilfs_sb_info *sbi)
696{
697 struct the_nilfs *nilfs = sbi->s_nilfs;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700698 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700699 int max_mnt_count = le16_to_cpu(sbp->s_max_mnt_count);
700 int mnt_count = le16_to_cpu(sbp->s_mnt_count);
701
702 /* nilfs->sem must be locked by the caller. */
703 if (!(nilfs->ns_mount_state & NILFS_VALID_FS)) {
704 printk(KERN_WARNING "NILFS warning: mounting unchecked fs\n");
705 } else if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
706 printk(KERN_WARNING
707 "NILFS warning: mounting fs with errors\n");
708#if 0
709 } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
710 printk(KERN_WARNING
711 "NILFS warning: maximal mount count reached\n");
712#endif
713 }
714 if (!max_mnt_count)
715 sbp->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
716
717 sbp->s_mnt_count = cpu_to_le16(mnt_count + 1);
718 sbp->s_state = cpu_to_le16(le16_to_cpu(sbp->s_state) & ~NILFS_VALID_FS);
719 sbp->s_mtime = cpu_to_le64(get_seconds());
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700720 return nilfs_commit_super(sbi, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700721}
722
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700723struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
724 u64 pos, int blocksize,
725 struct buffer_head **pbh)
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700726{
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700727 unsigned long long sb_index = pos;
728 unsigned long offset;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700729
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700730 offset = do_div(sb_index, blocksize);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700731 *pbh = sb_bread(sb, sb_index);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700732 if (!*pbh)
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700733 return NULL;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700734 return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
735}
736
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700737int nilfs_store_magic_and_option(struct super_block *sb,
738 struct nilfs_super_block *sbp,
739 char *data)
740{
741 struct nilfs_sb_info *sbi = NILFS_SB(sb);
742
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700743 sb->s_magic = le16_to_cpu(sbp->s_magic);
744
745 /* FS independent flags */
746#ifdef NILFS_ATIME_DISABLE
747 sb->s_flags |= MS_NOATIME;
748#endif
749
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700750 nilfs_set_default_options(sbi, sbp);
751
752 sbi->s_resuid = le16_to_cpu(sbp->s_def_resuid);
753 sbi->s_resgid = le16_to_cpu(sbp->s_def_resgid);
754 sbi->s_interval = le32_to_cpu(sbp->s_c_interval);
755 sbi->s_watermark = le32_to_cpu(sbp->s_c_block_max);
756
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700757 return !parse_options(data, sb) ? -EINVAL : 0 ;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700758}
759
760/**
761 * nilfs_fill_super() - initialize a super block instance
762 * @sb: super_block
763 * @data: mount options
764 * @silent: silent mode flag
765 * @nilfs: the_nilfs struct
766 *
767 * This function is called exclusively by bd_mount_mutex.
768 * So, the recovery process is protected from other simultaneous mounts.
769 */
770static int
771nilfs_fill_super(struct super_block *sb, void *data, int silent,
772 struct the_nilfs *nilfs)
773{
774 struct nilfs_sb_info *sbi;
775 struct inode *root;
776 __u64 cno;
777 int err;
778
779 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
780 if (!sbi)
781 return -ENOMEM;
782
783 sb->s_fs_info = sbi;
784
785 get_nilfs(nilfs);
786 sbi->s_nilfs = nilfs;
787 sbi->s_super = sb;
Ryusuke Konishi6dd47402009-06-08 01:39:31 +0900788 atomic_set(&sbi->s_count, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700789
790 err = init_nilfs(nilfs, sbi, (char *)data);
791 if (err)
792 goto failed_sbi;
793
794 spin_lock_init(&sbi->s_inode_lock);
795 INIT_LIST_HEAD(&sbi->s_dirty_files);
796 INIT_LIST_HEAD(&sbi->s_list);
797
798 /*
799 * Following initialization is overlapped because
800 * nilfs_sb_info structure has been cleared at the beginning.
801 * But we reserve them to keep our interest and make ready
802 * for the future change.
803 */
804 get_random_bytes(&sbi->s_next_generation,
805 sizeof(sbi->s_next_generation));
806 spin_lock_init(&sbi->s_next_gen_lock);
807
808 sb->s_op = &nilfs_sops;
809 sb->s_export_op = &nilfs_export_ops;
810 sb->s_root = NULL;
Ryusuke Konishi61239232009-04-06 19:02:00 -0700811 sb->s_time_gran = 1;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700812
813 if (!nilfs_loaded(nilfs)) {
814 err = load_nilfs(nilfs, sbi);
815 if (err)
816 goto failed_sbi;
817 }
818 cno = nilfs_last_cno(nilfs);
819
820 if (sb->s_flags & MS_RDONLY) {
821 if (nilfs_test_opt(sbi, SNAPSHOT)) {
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700822 err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,
823 sbi->s_snapshot_cno);
824 if (err < 0)
825 goto failed_sbi;
826 if (!err) {
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700827 printk(KERN_ERR
828 "NILFS: The specified checkpoint is "
829 "not a snapshot "
830 "(checkpoint number=%llu).\n",
831 (unsigned long long)sbi->s_snapshot_cno);
832 err = -EINVAL;
833 goto failed_sbi;
834 }
835 cno = sbi->s_snapshot_cno;
836 } else
837 /* Read-only mount */
838 sbi->s_snapshot_cno = cno;
839 }
840
841 err = nilfs_attach_checkpoint(sbi, cno);
842 if (err) {
843 printk(KERN_ERR "NILFS: error loading a checkpoint"
844 " (checkpoint number=%llu).\n", (unsigned long long)cno);
845 goto failed_sbi;
846 }
847
848 if (!(sb->s_flags & MS_RDONLY)) {
Ryusuke Konishicece5522009-04-06 19:01:58 -0700849 err = nilfs_attach_segment_constructor(sbi);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700850 if (err)
851 goto failed_checkpoint;
852 }
853
854 root = nilfs_iget(sb, NILFS_ROOT_INO);
855 if (IS_ERR(root)) {
856 printk(KERN_ERR "NILFS: get root inode failed\n");
857 err = PTR_ERR(root);
858 goto failed_segctor;
859 }
860 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
861 iput(root);
862 printk(KERN_ERR "NILFS: corrupt root inode.\n");
863 err = -EINVAL;
864 goto failed_segctor;
865 }
866 sb->s_root = d_alloc_root(root);
867 if (!sb->s_root) {
868 iput(root);
869 printk(KERN_ERR "NILFS: get root dentry failed\n");
870 err = -ENOMEM;
871 goto failed_segctor;
872 }
873
874 if (!(sb->s_flags & MS_RDONLY)) {
875 down_write(&nilfs->ns_sem);
876 nilfs_setup_super(sbi);
877 up_write(&nilfs->ns_sem);
878 }
879
880 err = nilfs_mark_recovery_complete(sbi);
881 if (unlikely(err)) {
882 printk(KERN_ERR "NILFS: recovery failed.\n");
883 goto failed_root;
884 }
885
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900886 down_write(&nilfs->ns_sem);
887 if (!nilfs_test_opt(sbi, SNAPSHOT))
888 nilfs->ns_current = sbi;
889 up_write(&nilfs->ns_sem);
890
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700891 return 0;
892
893 failed_root:
894 dput(sb->s_root);
895 sb->s_root = NULL;
896
897 failed_segctor:
898 nilfs_detach_segment_constructor(sbi);
899
900 failed_checkpoint:
901 nilfs_detach_checkpoint(sbi);
902
903 failed_sbi:
904 put_nilfs(nilfs);
905 sb->s_fs_info = NULL;
Ryusuke Konishi6dd47402009-06-08 01:39:31 +0900906 nilfs_put_sbinfo(sbi);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700907 return err;
908}
909
910static int nilfs_remount(struct super_block *sb, int *flags, char *data)
911{
912 struct nilfs_sb_info *sbi = NILFS_SB(sb);
913 struct nilfs_super_block *sbp;
914 struct the_nilfs *nilfs = sbi->s_nilfs;
915 unsigned long old_sb_flags;
916 struct nilfs_mount_options old_opts;
917 int err;
918
Alessio Igor Bogani337eb002009-05-12 15:10:54 +0200919 lock_kernel();
920
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700921 old_sb_flags = sb->s_flags;
922 old_opts.mount_opt = sbi->s_mount_opt;
923 old_opts.snapshot_cno = sbi->s_snapshot_cno;
924
925 if (!parse_options(data, sb)) {
926 err = -EINVAL;
927 goto restore_opts;
928 }
929 sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
930
931 if ((*flags & MS_RDONLY) &&
932 sbi->s_snapshot_cno != old_opts.snapshot_cno) {
933 printk(KERN_WARNING "NILFS (device %s): couldn't "
934 "remount to a different snapshot. \n",
935 sb->s_id);
936 err = -EINVAL;
937 goto restore_opts;
938 }
939
940 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
941 goto out;
942 if (*flags & MS_RDONLY) {
943 /* Shutting down the segment constructor */
944 nilfs_detach_segment_constructor(sbi);
945 sb->s_flags |= MS_RDONLY;
946
947 sbi->s_snapshot_cno = nilfs_last_cno(nilfs);
948 /* nilfs_set_opt(sbi, SNAPSHOT); */
949
950 /*
951 * Remounting a valid RW partition RDONLY, so set
952 * the RDONLY flag and then mark the partition as valid again.
953 */
954 down_write(&nilfs->ns_sem);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700955 sbp = nilfs->ns_sbp[0];
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700956 if (!(sbp->s_state & le16_to_cpu(NILFS_VALID_FS)) &&
957 (nilfs->ns_mount_state & NILFS_VALID_FS))
958 sbp->s_state = cpu_to_le16(nilfs->ns_mount_state);
959 sbp->s_mtime = cpu_to_le64(get_seconds());
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700960 nilfs_commit_super(sbi, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700961 up_write(&nilfs->ns_sem);
962 } else {
963 /*
964 * Mounting a RDONLY partition read-write, so reread and
965 * store the current valid flag. (It may have been changed
966 * by fsck since we originally mounted the partition.)
967 */
968 down(&sb->s_bdev->bd_mount_sem);
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900969 down_read(&nilfs->ns_sem);
970 if (nilfs->ns_current && nilfs->ns_current != sbi) {
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700971 printk(KERN_WARNING "NILFS (device %s): couldn't "
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900972 "remount because an RW-mount exists.\n",
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700973 sb->s_id);
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900974 up_read(&nilfs->ns_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700975 err = -EBUSY;
976 goto rw_remount_failed;
977 }
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900978 up_read(&nilfs->ns_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700979 if (sbi->s_snapshot_cno != nilfs_last_cno(nilfs)) {
980 printk(KERN_WARNING "NILFS (device %s): couldn't "
981 "remount because the current RO-mount is not "
982 "the latest one.\n",
983 sb->s_id);
984 err = -EINVAL;
985 goto rw_remount_failed;
986 }
987 sb->s_flags &= ~MS_RDONLY;
988 nilfs_clear_opt(sbi, SNAPSHOT);
989 sbi->s_snapshot_cno = 0;
990
Ryusuke Konishicece5522009-04-06 19:01:58 -0700991 err = nilfs_attach_segment_constructor(sbi);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700992 if (err)
993 goto rw_remount_failed;
994
995 down_write(&nilfs->ns_sem);
996 nilfs_setup_super(sbi);
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900997 nilfs->ns_current = sbi;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700998 up_write(&nilfs->ns_sem);
999
1000 up(&sb->s_bdev->bd_mount_sem);
1001 }
1002 out:
Alessio Igor Bogani337eb002009-05-12 15:10:54 +02001003 unlock_kernel();
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001004 return 0;
1005
1006 rw_remount_failed:
1007 up(&sb->s_bdev->bd_mount_sem);
1008 restore_opts:
1009 sb->s_flags = old_sb_flags;
1010 sbi->s_mount_opt = old_opts.mount_opt;
1011 sbi->s_snapshot_cno = old_opts.snapshot_cno;
Alessio Igor Bogani337eb002009-05-12 15:10:54 +02001012 unlock_kernel();
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001013 return err;
1014}
1015
1016struct nilfs_super_data {
1017 struct block_device *bdev;
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001018 struct nilfs_sb_info *sbi;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001019 __u64 cno;
1020 int flags;
1021};
1022
1023/**
1024 * nilfs_identify - pre-read mount options needed to identify mount instance
1025 * @data: mount options
1026 * @sd: nilfs_super_data
1027 */
1028static int nilfs_identify(char *data, struct nilfs_super_data *sd)
1029{
1030 char *p, *options = data;
1031 substring_t args[MAX_OPT_ARGS];
1032 int option, token;
1033 int ret = 0;
1034
1035 do {
1036 p = strsep(&options, ",");
1037 if (p != NULL && *p) {
1038 token = match_token(p, tokens, args);
1039 if (token == Opt_snapshot) {
1040 if (!(sd->flags & MS_RDONLY))
1041 ret++;
1042 else {
1043 ret = match_int(&args[0], &option);
1044 if (!ret) {
1045 if (option > 0)
1046 sd->cno = option;
1047 else
1048 ret++;
1049 }
1050 }
1051 }
1052 if (ret)
1053 printk(KERN_ERR
1054 "NILFS: invalid mount option: %s\n", p);
1055 }
1056 if (!options)
1057 break;
1058 BUG_ON(options == data);
1059 *(options - 1) = ',';
1060 } while (!ret);
1061 return ret;
1062}
1063
1064static int nilfs_set_bdev_super(struct super_block *s, void *data)
1065{
1066 struct nilfs_super_data *sd = data;
1067
1068 s->s_bdev = sd->bdev;
1069 s->s_dev = s->s_bdev->bd_dev;
1070 return 0;
1071}
1072
1073static int nilfs_test_bdev_super(struct super_block *s, void *data)
1074{
1075 struct nilfs_super_data *sd = data;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001076
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001077 return sd->sbi && s->s_fs_info == (void *)sd->sbi;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001078}
1079
1080static int
1081nilfs_get_sb(struct file_system_type *fs_type, int flags,
1082 const char *dev_name, void *data, struct vfsmount *mnt)
1083{
1084 struct nilfs_super_data sd;
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001085 struct super_block *s;
1086 struct the_nilfs *nilfs;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001087 int err, need_to_close = 1;
1088
1089 sd.bdev = open_bdev_exclusive(dev_name, flags, fs_type);
1090 if (IS_ERR(sd.bdev))
1091 return PTR_ERR(sd.bdev);
1092
1093 /*
1094 * To get mount instance using sget() vfs-routine, NILFS needs
1095 * much more information than normal filesystems to identify mount
1096 * instance. For snapshot mounts, not only a mount type (ro-mount
1097 * or rw-mount) but also a checkpoint number is required.
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001098 */
1099 sd.cno = 0;
1100 sd.flags = flags;
1101 if (nilfs_identify((char *)data, &sd)) {
1102 err = -EINVAL;
1103 goto failed;
1104 }
1105
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001106 nilfs = find_or_create_nilfs(sd.bdev);
1107 if (!nilfs) {
1108 err = -ENOMEM;
1109 goto failed;
1110 }
1111
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001112 down(&sd.bdev->bd_mount_sem);
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +09001113
1114 if (!sd.cno) {
1115 /*
1116 * Check if an exclusive mount exists or not.
1117 * Snapshot mounts coexist with a current mount
1118 * (i.e. rw-mount or ro-mount), whereas rw-mount and
1119 * ro-mount are mutually exclusive.
1120 */
1121 down_read(&nilfs->ns_sem);
1122 if (nilfs->ns_current &&
1123 ((nilfs->ns_current->s_super->s_flags ^ flags)
1124 & MS_RDONLY)) {
1125 up_read(&nilfs->ns_sem);
1126 err = -EBUSY;
1127 goto failed_unlock;
1128 }
1129 up_read(&nilfs->ns_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001130 }
1131
1132 /*
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001133 * Find existing nilfs_sb_info struct
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001134 */
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001135 sd.sbi = nilfs_find_sbinfo(nilfs, !(flags & MS_RDONLY), sd.cno);
1136
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001137 if (!sd.cno)
1138 /* trying to get the latest checkpoint. */
1139 sd.cno = nilfs_last_cno(nilfs);
1140
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001141 /*
1142 * Get super block instance holding the nilfs_sb_info struct.
1143 * A new instance is allocated if no existing mount is present or
1144 * existing instance has been unmounted.
1145 */
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001146 s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, &sd);
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001147 if (sd.sbi)
1148 nilfs_put_sbinfo(sd.sbi);
1149
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001150 if (IS_ERR(s)) {
1151 err = PTR_ERR(s);
1152 goto failed_unlock;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001153 }
1154
1155 if (!s->s_root) {
1156 char b[BDEVNAME_SIZE];
1157
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001158 /* New superblock instance created */
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001159 s->s_flags = flags;
1160 strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
1161 sb_set_blocksize(s, block_size(sd.bdev));
1162
1163 err = nilfs_fill_super(s, data, flags & MS_VERBOSE, nilfs);
1164 if (err)
1165 goto cancel_new;
1166
1167 s->s_flags |= MS_ACTIVE;
1168 need_to_close = 0;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001169 }
1170
1171 up(&sd.bdev->bd_mount_sem);
1172 put_nilfs(nilfs);
1173 if (need_to_close)
1174 close_bdev_exclusive(sd.bdev, flags);
1175 simple_set_mnt(mnt, s);
1176 return 0;
1177
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001178 failed_unlock:
1179 up(&sd.bdev->bd_mount_sem);
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001180 put_nilfs(nilfs);
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001181 failed:
1182 close_bdev_exclusive(sd.bdev, flags);
1183
1184 return err;
1185
1186 cancel_new:
1187 /* Abandoning the newly allocated superblock */
1188 up(&sd.bdev->bd_mount_sem);
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001189 put_nilfs(nilfs);
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001190 up_write(&s->s_umount);
1191 deactivate_super(s);
1192 /*
1193 * deactivate_super() invokes close_bdev_exclusive().
1194 * We must finish all post-cleaning before this call;
1195 * put_nilfs() and unlocking bd_mount_sem need the block device.
1196 */
1197 return err;
1198}
1199
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001200struct file_system_type nilfs_fs_type = {
1201 .owner = THIS_MODULE,
1202 .name = "nilfs2",
1203 .get_sb = nilfs_get_sb,
1204 .kill_sb = kill_block_super,
1205 .fs_flags = FS_REQUIRES_DEV,
1206};
1207
1208static int __init init_nilfs_fs(void)
1209{
1210 int err;
1211
1212 err = nilfs_init_inode_cache();
1213 if (err)
1214 goto failed;
1215
1216 err = nilfs_init_transaction_cache();
1217 if (err)
1218 goto failed_inode_cache;
1219
1220 err = nilfs_init_segbuf_cache();
1221 if (err)
1222 goto failed_transaction_cache;
1223
1224 err = nilfs_btree_path_cache_init();
1225 if (err)
1226 goto failed_segbuf_cache;
1227
1228 err = register_filesystem(&nilfs_fs_type);
1229 if (err)
1230 goto failed_btree_path_cache;
1231
1232 return 0;
1233
1234 failed_btree_path_cache:
1235 nilfs_btree_path_cache_destroy();
1236
1237 failed_segbuf_cache:
1238 nilfs_destroy_segbuf_cache();
1239
1240 failed_transaction_cache:
1241 nilfs_destroy_transaction_cache();
1242
1243 failed_inode_cache:
1244 nilfs_destroy_inode_cache();
1245
1246 failed:
1247 return err;
1248}
1249
1250static void __exit exit_nilfs_fs(void)
1251{
1252 nilfs_destroy_segbuf_cache();
1253 nilfs_destroy_transaction_cache();
1254 nilfs_destroy_inode_cache();
1255 nilfs_btree_path_cache_destroy();
1256 unregister_filesystem(&nilfs_fs_type);
1257}
1258
1259module_init(init_nilfs_fs)
1260module_exit(exit_nilfs_fs)