blob: 0cdbc5e7655a60129adbbc69ebbae8830f8d1645 [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>
Jiro SEKIBAb58a2852009-06-24 20:06:34 +090053#include <linux/seq_file.h>
54#include <linux/mount.h>
Ryusuke Konishi783f6182009-04-06 19:01:35 -070055#include "nilfs.h"
56#include "mdt.h"
57#include "alloc.h"
58#include "page.h"
59#include "cpfile.h"
60#include "ifile.h"
61#include "dat.h"
62#include "segment.h"
63#include "segbuf.h"
64
65MODULE_AUTHOR("NTT Corp.");
66MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
67 "(NILFS)");
Ryusuke Konishi783f6182009-04-06 19:01:35 -070068MODULE_LICENSE("GPL");
69
70static int nilfs_remount(struct super_block *sb, int *flags, char *data);
Ryusuke Konishi783f6182009-04-06 19:01:35 -070071
72/**
73 * nilfs_error() - report failure condition on a filesystem
74 *
75 * nilfs_error() sets an ERROR_FS flag on the superblock as well as
76 * reporting an error message. It should be called when NILFS detects
77 * incoherences or defects of meta data on disk. As for sustainable
78 * errors such as a single-shot I/O error, nilfs_warning() or the printk()
79 * function should be used instead.
80 *
81 * The segment constructor must not call this function because it can
82 * kill itself.
83 */
84void nilfs_error(struct super_block *sb, const char *function,
85 const char *fmt, ...)
86{
87 struct nilfs_sb_info *sbi = NILFS_SB(sb);
88 va_list args;
89
90 va_start(args, fmt);
91 printk(KERN_CRIT "NILFS error (device %s): %s: ", sb->s_id, function);
92 vprintk(fmt, args);
93 printk("\n");
94 va_end(args);
95
96 if (!(sb->s_flags & MS_RDONLY)) {
97 struct the_nilfs *nilfs = sbi->s_nilfs;
98
Ryusuke Konishi783f6182009-04-06 19:01:35 -070099 down_write(&nilfs->ns_sem);
100 if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
101 nilfs->ns_mount_state |= NILFS_ERROR_FS;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700102 nilfs->ns_sbp[0]->s_state |=
103 cpu_to_le16(NILFS_ERROR_FS);
104 nilfs_commit_super(sbi, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700105 }
106 up_write(&nilfs->ns_sem);
107
108 if (nilfs_test_opt(sbi, ERRORS_RO)) {
109 printk(KERN_CRIT "Remounting filesystem read-only\n");
110 sb->s_flags |= MS_RDONLY;
111 }
112 }
113
114 if (nilfs_test_opt(sbi, ERRORS_PANIC))
115 panic("NILFS (device %s): panic forced after error\n",
116 sb->s_id);
117}
118
119void nilfs_warning(struct super_block *sb, const char *function,
120 const char *fmt, ...)
121{
122 va_list args;
123
124 va_start(args, fmt);
125 printk(KERN_WARNING "NILFS warning (device %s): %s: ",
126 sb->s_id, function);
127 vprintk(fmt, args);
128 printk("\n");
129 va_end(args);
130}
131
132static struct kmem_cache *nilfs_inode_cachep;
133
Ryusuke Konishia53b4752009-05-27 22:11:46 +0900134struct inode *nilfs_alloc_inode_common(struct the_nilfs *nilfs)
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700135{
136 struct nilfs_inode_info *ii;
137
138 ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS);
139 if (!ii)
140 return NULL;
141 ii->i_bh = NULL;
142 ii->i_state = 0;
143 ii->vfs_inode.i_version = 1;
Ryusuke Konishia53b4752009-05-27 22:11:46 +0900144 nilfs_btnode_cache_init(&ii->i_btnode_cache, nilfs->ns_bdi);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700145 return &ii->vfs_inode;
146}
147
Ryusuke Konishia53b4752009-05-27 22:11:46 +0900148struct inode *nilfs_alloc_inode(struct super_block *sb)
149{
150 return nilfs_alloc_inode_common(NILFS_SB(sb)->s_nilfs);
151}
152
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700153void nilfs_destroy_inode(struct inode *inode)
154{
155 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
156}
157
158static void init_once(void *obj)
159{
160 struct nilfs_inode_info *ii = obj;
161
162 INIT_LIST_HEAD(&ii->i_dirty);
163#ifdef CONFIG_NILFS_XATTR
164 init_rwsem(&ii->xattr_sem);
165#endif
166 nilfs_btnode_cache_init_once(&ii->i_btnode_cache);
167 ii->i_bmap = (struct nilfs_bmap *)&ii->i_bmap_union;
168 inode_init_once(&ii->vfs_inode);
169}
170
171static int nilfs_init_inode_cache(void)
172{
173 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
174 sizeof(struct nilfs_inode_info),
175 0, SLAB_RECLAIM_ACCOUNT,
176 init_once);
177
178 return (nilfs_inode_cachep == NULL) ? -ENOMEM : 0;
179}
180
181static inline void nilfs_destroy_inode_cache(void)
182{
183 kmem_cache_destroy(nilfs_inode_cachep);
184}
185
186static void nilfs_clear_inode(struct inode *inode)
187{
188 struct nilfs_inode_info *ii = NILFS_I(inode);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700189
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700190 /*
191 * Free resources allocated in nilfs_read_inode(), here.
192 */
Ryusuke Konishia2e7d2d2009-04-06 19:01:44 -0700193 BUG_ON(!list_empty(&ii->i_dirty));
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700194 brelse(ii->i_bh);
195 ii->i_bh = NULL;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700196
197 if (test_bit(NILFS_I_BMAP, &ii->i_state))
198 nilfs_bmap_clear(ii->i_bmap);
199
200 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700201}
202
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700203static int nilfs_sync_super(struct nilfs_sb_info *sbi, int dupsb)
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700204{
205 struct the_nilfs *nilfs = sbi->s_nilfs;
206 int err;
207 int barrier_done = 0;
208
209 if (nilfs_test_opt(sbi, BARRIER)) {
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700210 set_buffer_ordered(nilfs->ns_sbh[0]);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700211 barrier_done = 1;
212 }
213 retry:
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700214 set_buffer_dirty(nilfs->ns_sbh[0]);
215 err = sync_dirty_buffer(nilfs->ns_sbh[0]);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700216 if (err == -EOPNOTSUPP && barrier_done) {
217 nilfs_warning(sbi->s_super, __func__,
218 "barrier-based sync failed. "
219 "disabling barriers\n");
220 nilfs_clear_opt(sbi, BARRIER);
221 barrier_done = 0;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700222 clear_buffer_ordered(nilfs->ns_sbh[0]);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700223 goto retry;
224 }
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700225 if (unlikely(err)) {
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700226 printk(KERN_ERR
227 "NILFS: unable to write superblock (err=%d)\n", err);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700228 if (err == -EIO && nilfs->ns_sbh[1]) {
229 nilfs_fall_back_super_block(nilfs);
230 goto retry;
231 }
232 } else {
233 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
234
235 /*
236 * The latest segment becomes trailable from the position
237 * written in superblock.
238 */
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700239 clear_nilfs_discontinued(nilfs);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700240
241 /* update GC protection for recent segments */
242 if (nilfs->ns_sbh[1]) {
243 sbp = NULL;
244 if (dupsb) {
245 set_buffer_dirty(nilfs->ns_sbh[1]);
246 if (!sync_dirty_buffer(nilfs->ns_sbh[1]))
247 sbp = nilfs->ns_sbp[1];
248 }
249 }
250 if (sbp) {
251 spin_lock(&nilfs->ns_last_segment_lock);
252 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
253 spin_unlock(&nilfs->ns_last_segment_lock);
254 }
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700255 }
256
257 return err;
258}
259
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700260int nilfs_commit_super(struct nilfs_sb_info *sbi, int dupsb)
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700261{
262 struct the_nilfs *nilfs = sbi->s_nilfs;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700263 struct nilfs_super_block **sbp = nilfs->ns_sbp;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700264 sector_t nfreeblocks;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700265 time_t t;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700266 int err;
267
268 /* nilfs->sem must be locked by the caller. */
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700269 if (sbp[0]->s_magic != NILFS_SUPER_MAGIC) {
270 if (sbp[1] && sbp[1]->s_magic == NILFS_SUPER_MAGIC)
271 nilfs_swap_super_block(nilfs);
272 else {
273 printk(KERN_CRIT "NILFS: superblock broke on dev %s\n",
274 sbi->s_super->s_id);
275 return -EIO;
276 }
277 }
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700278 err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
279 if (unlikely(err)) {
280 printk(KERN_ERR "NILFS: failed to count free blocks\n");
281 return err;
282 }
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700283 spin_lock(&nilfs->ns_last_segment_lock);
284 sbp[0]->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
285 sbp[0]->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
286 sbp[0]->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
287 spin_unlock(&nilfs->ns_last_segment_lock);
288
289 t = get_seconds();
290 nilfs->ns_sbwtime[0] = t;
291 sbp[0]->s_free_blocks_count = cpu_to_le64(nfreeblocks);
292 sbp[0]->s_wtime = cpu_to_le64(t);
293 sbp[0]->s_sum = 0;
294 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
295 (unsigned char *)sbp[0],
296 nilfs->ns_sbsize));
297 if (dupsb && sbp[1]) {
298 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
299 nilfs->ns_sbwtime[1] = t;
300 }
Ryusuke Konishie605f0a2009-12-09 00:57:52 +0900301 clear_nilfs_sb_dirty(nilfs);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700302 return nilfs_sync_super(sbi, dupsb);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700303}
304
305static void nilfs_put_super(struct super_block *sb)
306{
307 struct nilfs_sb_info *sbi = NILFS_SB(sb);
308 struct the_nilfs *nilfs = sbi->s_nilfs;
309
Christoph Hellwig6cfd0142009-05-05 15:40:36 +0200310 lock_kernel();
311
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700312 nilfs_detach_segment_constructor(sbi);
313
314 if (!(sb->s_flags & MS_RDONLY)) {
315 down_write(&nilfs->ns_sem);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700316 nilfs->ns_sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state);
317 nilfs_commit_super(sbi, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700318 up_write(&nilfs->ns_sem);
319 }
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900320 down_write(&nilfs->ns_super_sem);
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900321 if (nilfs->ns_current == sbi)
322 nilfs->ns_current = NULL;
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900323 up_write(&nilfs->ns_super_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700324
325 nilfs_detach_checkpoint(sbi);
326 put_nilfs(sbi->s_nilfs);
327 sbi->s_super = NULL;
328 sb->s_fs_info = NULL;
Ryusuke Konishi6dd47402009-06-08 01:39:31 +0900329 nilfs_put_sbinfo(sbi);
Christoph Hellwig6cfd0142009-05-05 15:40:36 +0200330
331 unlock_kernel();
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700332}
333
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700334static int nilfs_sync_fs(struct super_block *sb, int wait)
335{
Jiro SEKIBA6233caa2009-07-23 01:26:33 +0900336 struct nilfs_sb_info *sbi = NILFS_SB(sb);
337 struct the_nilfs *nilfs = sbi->s_nilfs;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700338 int err = 0;
339
340 /* This function is called when super block should be written back */
341 if (wait)
342 err = nilfs_construct_segment(sb);
Jiro SEKIBA6233caa2009-07-23 01:26:33 +0900343
344 down_write(&nilfs->ns_sem);
Ryusuke Konishie605f0a2009-12-09 00:57:52 +0900345 if (nilfs_sb_dirty(nilfs))
Jiro SEKIBA6233caa2009-07-23 01:26:33 +0900346 nilfs_commit_super(sbi, 1);
347 up_write(&nilfs->ns_sem);
348
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700349 return err;
350}
351
352int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno)
353{
354 struct the_nilfs *nilfs = sbi->s_nilfs;
355 struct nilfs_checkpoint *raw_cp;
356 struct buffer_head *bh_cp;
357 int err;
358
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900359 down_write(&nilfs->ns_super_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700360 list_add(&sbi->s_list, &nilfs->ns_supers);
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900361 up_write(&nilfs->ns_super_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700362
Ryusuke Konishi79739562009-11-12 23:56:43 +0900363 sbi->s_ifile = nilfs_ifile_new(sbi, nilfs->ns_inode_size);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700364 if (!sbi->s_ifile)
365 return -ENOMEM;
366
Zhang Qiang1154ecb2009-08-18 14:58:24 +0800367 down_read(&nilfs->ns_segctor_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700368 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
369 &bh_cp);
Zhang Qiang1154ecb2009-08-18 14:58:24 +0800370 up_read(&nilfs->ns_segctor_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700371 if (unlikely(err)) {
372 if (err == -ENOENT || err == -EINVAL) {
373 printk(KERN_ERR
374 "NILFS: Invalid checkpoint "
375 "(checkpoint number=%llu)\n",
376 (unsigned long long)cno);
377 err = -EINVAL;
378 }
379 goto failed;
380 }
381 err = nilfs_read_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode);
382 if (unlikely(err))
383 goto failed_bh;
384 atomic_set(&sbi->s_inodes_count, le64_to_cpu(raw_cp->cp_inodes_count));
385 atomic_set(&sbi->s_blocks_count, le64_to_cpu(raw_cp->cp_blocks_count));
386
387 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
388 return 0;
389
390 failed_bh:
391 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
392 failed:
393 nilfs_mdt_destroy(sbi->s_ifile);
394 sbi->s_ifile = NULL;
395
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900396 down_write(&nilfs->ns_super_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700397 list_del_init(&sbi->s_list);
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900398 up_write(&nilfs->ns_super_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700399
400 return err;
401}
402
403void nilfs_detach_checkpoint(struct nilfs_sb_info *sbi)
404{
405 struct the_nilfs *nilfs = sbi->s_nilfs;
406
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700407 nilfs_mdt_destroy(sbi->s_ifile);
408 sbi->s_ifile = NULL;
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900409 down_write(&nilfs->ns_super_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700410 list_del_init(&sbi->s_list);
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900411 up_write(&nilfs->ns_super_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700412}
413
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700414static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
415{
416 struct super_block *sb = dentry->d_sb;
417 struct nilfs_sb_info *sbi = NILFS_SB(sb);
Ryusuke Konishic306af22009-03-26 10:16:57 +0900418 struct the_nilfs *nilfs = sbi->s_nilfs;
419 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700420 unsigned long long blocks;
421 unsigned long overhead;
422 unsigned long nrsvblocks;
423 sector_t nfreeblocks;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700424 int err;
425
426 /*
427 * Compute all of the segment blocks
428 *
429 * The blocks before first segment and after last segment
430 * are excluded.
431 */
432 blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments
433 - nilfs->ns_first_data_block;
434 nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment;
435
436 /*
437 * Compute the overhead
438 *
Ryusuke Konishi7a650042010-03-14 03:32:40 +0900439 * When distributing meta data blocks outside segment structure,
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700440 * We must count them as the overhead.
441 */
442 overhead = 0;
443
444 err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
445 if (unlikely(err))
446 return err;
447
448 buf->f_type = NILFS_SUPER_MAGIC;
449 buf->f_bsize = sb->s_blocksize;
450 buf->f_blocks = blocks - overhead;
451 buf->f_bfree = nfreeblocks;
452 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
453 (buf->f_bfree - nrsvblocks) : 0;
454 buf->f_files = atomic_read(&sbi->s_inodes_count);
455 buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */
456 buf->f_namelen = NILFS_NAME_LEN;
Ryusuke Konishic306af22009-03-26 10:16:57 +0900457 buf->f_fsid.val[0] = (u32)id;
458 buf->f_fsid.val[1] = (u32)(id >> 32);
459
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700460 return 0;
461}
462
Jiro SEKIBAb58a2852009-06-24 20:06:34 +0900463static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
464{
465 struct super_block *sb = vfs->mnt_sb;
466 struct nilfs_sb_info *sbi = NILFS_SB(sb);
467
468 if (!nilfs_test_opt(sbi, BARRIER))
Jiro SEKIBA91f19532009-11-12 14:07:26 +0900469 seq_printf(seq, ",nobarrier");
Jiro SEKIBAb58a2852009-06-24 20:06:34 +0900470 if (nilfs_test_opt(sbi, SNAPSHOT))
471 seq_printf(seq, ",cp=%llu",
472 (unsigned long long int)sbi->s_snapshot_cno);
473 if (nilfs_test_opt(sbi, ERRORS_RO))
474 seq_printf(seq, ",errors=remount-ro");
475 if (nilfs_test_opt(sbi, ERRORS_PANIC))
476 seq_printf(seq, ",errors=panic");
477 if (nilfs_test_opt(sbi, STRICT_ORDER))
478 seq_printf(seq, ",order=strict");
Ryusuke Konishi02345762009-11-20 03:28:01 +0900479 if (nilfs_test_opt(sbi, NORECOVERY))
480 seq_printf(seq, ",norecovery");
Jiro SEKIBAe902ec92010-01-30 18:06:35 +0900481 if (nilfs_test_opt(sbi, DISCARD))
482 seq_printf(seq, ",discard");
Jiro SEKIBAb58a2852009-06-24 20:06:34 +0900483
484 return 0;
485}
486
Alexey Dobriyanb87221d2009-09-21 17:01:09 -0700487static const struct super_operations nilfs_sops = {
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700488 .alloc_inode = nilfs_alloc_inode,
489 .destroy_inode = nilfs_destroy_inode,
490 .dirty_inode = nilfs_dirty_inode,
491 /* .write_inode = nilfs_write_inode, */
492 /* .put_inode = nilfs_put_inode, */
493 /* .drop_inode = nilfs_drop_inode, */
494 .delete_inode = nilfs_delete_inode,
495 .put_super = nilfs_put_super,
Jiro SEKIBA1dfa2712009-07-23 01:33:49 +0900496 /* .write_super = nilfs_write_super, */
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700497 .sync_fs = nilfs_sync_fs,
498 /* .write_super_lockfs */
499 /* .unlockfs */
500 .statfs = nilfs_statfs,
501 .remount_fs = nilfs_remount,
502 .clear_inode = nilfs_clear_inode,
503 /* .umount_begin */
Jiro SEKIBAb58a2852009-06-24 20:06:34 +0900504 .show_options = nilfs_show_options
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700505};
506
507static struct inode *
508nilfs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation)
509{
510 struct inode *inode;
511
512 if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO &&
513 ino != NILFS_SKETCH_INO)
514 return ERR_PTR(-ESTALE);
515
516 inode = nilfs_iget(sb, ino);
517 if (IS_ERR(inode))
518 return ERR_CAST(inode);
519 if (generation && inode->i_generation != generation) {
520 iput(inode);
521 return ERR_PTR(-ESTALE);
522 }
523
524 return inode;
525}
526
527static struct dentry *
528nilfs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len,
529 int fh_type)
530{
531 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
532 nilfs_nfs_get_inode);
533}
534
535static struct dentry *
536nilfs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len,
537 int fh_type)
538{
539 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
540 nilfs_nfs_get_inode);
541}
542
Alexey Dobriyanac4cfdd2009-09-21 17:01:10 -0700543static const struct export_operations nilfs_export_ops = {
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700544 .fh_to_dentry = nilfs_fh_to_dentry,
545 .fh_to_parent = nilfs_fh_to_parent,
546 .get_parent = nilfs_get_parent,
547};
548
549enum {
550 Opt_err_cont, Opt_err_panic, Opt_err_ro,
Ryusuke Konishi02345762009-11-20 03:28:01 +0900551 Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,
Jiro SEKIBAe902ec92010-01-30 18:06:35 +0900552 Opt_discard, Opt_err,
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700553};
554
555static match_table_t tokens = {
556 {Opt_err_cont, "errors=continue"},
557 {Opt_err_panic, "errors=panic"},
558 {Opt_err_ro, "errors=remount-ro"},
Jiro SEKIBA91f19532009-11-12 14:07:26 +0900559 {Opt_nobarrier, "nobarrier"},
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700560 {Opt_snapshot, "cp=%u"},
561 {Opt_order, "order=%s"},
Ryusuke Konishi02345762009-11-20 03:28:01 +0900562 {Opt_norecovery, "norecovery"},
Jiro SEKIBAe902ec92010-01-30 18:06:35 +0900563 {Opt_discard, "discard"},
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700564 {Opt_err, NULL}
565};
566
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700567static int parse_options(char *options, struct super_block *sb)
568{
569 struct nilfs_sb_info *sbi = NILFS_SB(sb);
570 char *p;
571 substring_t args[MAX_OPT_ARGS];
572 int option;
573
574 if (!options)
575 return 1;
576
577 while ((p = strsep(&options, ",")) != NULL) {
578 int token;
579 if (!*p)
580 continue;
581
582 token = match_token(p, tokens, args);
583 switch (token) {
Jiro SEKIBA91f19532009-11-12 14:07:26 +0900584 case Opt_nobarrier:
585 nilfs_clear_opt(sbi, BARRIER);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700586 break;
587 case Opt_order:
588 if (strcmp(args[0].from, "relaxed") == 0)
589 /* Ordered data semantics */
590 nilfs_clear_opt(sbi, STRICT_ORDER);
591 else if (strcmp(args[0].from, "strict") == 0)
592 /* Strict in-order semantics */
593 nilfs_set_opt(sbi, STRICT_ORDER);
594 else
595 return 0;
596 break;
597 case Opt_err_panic:
598 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_PANIC);
599 break;
600 case Opt_err_ro:
601 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_RO);
602 break;
603 case Opt_err_cont:
604 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_CONT);
605 break;
606 case Opt_snapshot:
607 if (match_int(&args[0], &option) || option <= 0)
608 return 0;
609 if (!(sb->s_flags & MS_RDONLY))
610 return 0;
611 sbi->s_snapshot_cno = option;
612 nilfs_set_opt(sbi, SNAPSHOT);
613 break;
Ryusuke Konishi02345762009-11-20 03:28:01 +0900614 case Opt_norecovery:
615 nilfs_set_opt(sbi, NORECOVERY);
616 break;
Jiro SEKIBAe902ec92010-01-30 18:06:35 +0900617 case Opt_discard:
618 nilfs_set_opt(sbi, DISCARD);
619 break;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700620 default:
621 printk(KERN_ERR
622 "NILFS: Unrecognized mount option \"%s\"\n", p);
623 return 0;
624 }
625 }
626 return 1;
627}
628
629static inline void
630nilfs_set_default_options(struct nilfs_sb_info *sbi,
631 struct nilfs_super_block *sbp)
632{
633 sbi->s_mount_opt =
634 NILFS_MOUNT_ERRORS_CONT | NILFS_MOUNT_BARRIER;
635}
636
637static int nilfs_setup_super(struct nilfs_sb_info *sbi)
638{
639 struct the_nilfs *nilfs = sbi->s_nilfs;
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700640 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700641 int max_mnt_count = le16_to_cpu(sbp->s_max_mnt_count);
642 int mnt_count = le16_to_cpu(sbp->s_mnt_count);
643
644 /* nilfs->sem must be locked by the caller. */
Ryusuke Konishif50a4c82009-11-19 16:58:40 +0900645 if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700646 printk(KERN_WARNING
647 "NILFS warning: mounting fs with errors\n");
648#if 0
649 } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
650 printk(KERN_WARNING
651 "NILFS warning: maximal mount count reached\n");
652#endif
653 }
654 if (!max_mnt_count)
655 sbp->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
656
657 sbp->s_mnt_count = cpu_to_le16(mnt_count + 1);
658 sbp->s_state = cpu_to_le16(le16_to_cpu(sbp->s_state) & ~NILFS_VALID_FS);
659 sbp->s_mtime = cpu_to_le64(get_seconds());
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700660 return nilfs_commit_super(sbi, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700661}
662
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700663struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
664 u64 pos, int blocksize,
665 struct buffer_head **pbh)
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700666{
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700667 unsigned long long sb_index = pos;
668 unsigned long offset;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700669
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700670 offset = do_div(sb_index, blocksize);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700671 *pbh = sb_bread(sb, sb_index);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700672 if (!*pbh)
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700673 return NULL;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700674 return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
675}
676
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700677int nilfs_store_magic_and_option(struct super_block *sb,
678 struct nilfs_super_block *sbp,
679 char *data)
680{
681 struct nilfs_sb_info *sbi = NILFS_SB(sb);
682
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700683 sb->s_magic = le16_to_cpu(sbp->s_magic);
684
685 /* FS independent flags */
686#ifdef NILFS_ATIME_DISABLE
687 sb->s_flags |= MS_NOATIME;
688#endif
689
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700690 nilfs_set_default_options(sbi, sbp);
691
692 sbi->s_resuid = le16_to_cpu(sbp->s_def_resuid);
693 sbi->s_resgid = le16_to_cpu(sbp->s_def_resgid);
694 sbi->s_interval = le32_to_cpu(sbp->s_c_interval);
695 sbi->s_watermark = le32_to_cpu(sbp->s_c_block_max);
696
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700697 return !parse_options(data, sb) ? -EINVAL : 0 ;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700698}
699
700/**
701 * nilfs_fill_super() - initialize a super block instance
702 * @sb: super_block
703 * @data: mount options
704 * @silent: silent mode flag
705 * @nilfs: the_nilfs struct
706 *
Ryusuke Konishiaa7dfb82009-06-08 01:39:33 +0900707 * This function is called exclusively by nilfs->ns_mount_mutex.
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700708 * So, the recovery process is protected from other simultaneous mounts.
709 */
710static int
711nilfs_fill_super(struct super_block *sb, void *data, int silent,
712 struct the_nilfs *nilfs)
713{
714 struct nilfs_sb_info *sbi;
715 struct inode *root;
716 __u64 cno;
717 int err;
718
719 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
720 if (!sbi)
721 return -ENOMEM;
722
723 sb->s_fs_info = sbi;
724
725 get_nilfs(nilfs);
726 sbi->s_nilfs = nilfs;
727 sbi->s_super = sb;
Ryusuke Konishi6dd47402009-06-08 01:39:31 +0900728 atomic_set(&sbi->s_count, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700729
730 err = init_nilfs(nilfs, sbi, (char *)data);
731 if (err)
732 goto failed_sbi;
733
734 spin_lock_init(&sbi->s_inode_lock);
735 INIT_LIST_HEAD(&sbi->s_dirty_files);
736 INIT_LIST_HEAD(&sbi->s_list);
737
738 /*
739 * Following initialization is overlapped because
740 * nilfs_sb_info structure has been cleared at the beginning.
741 * But we reserve them to keep our interest and make ready
742 * for the future change.
743 */
744 get_random_bytes(&sbi->s_next_generation,
745 sizeof(sbi->s_next_generation));
746 spin_lock_init(&sbi->s_next_gen_lock);
747
748 sb->s_op = &nilfs_sops;
749 sb->s_export_op = &nilfs_export_ops;
750 sb->s_root = NULL;
Ryusuke Konishi61239232009-04-06 19:02:00 -0700751 sb->s_time_gran = 1;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700752
Ryusuke Konishif50a4c82009-11-19 16:58:40 +0900753 err = load_nilfs(nilfs, sbi);
754 if (err)
755 goto failed_sbi;
756
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700757 cno = nilfs_last_cno(nilfs);
758
759 if (sb->s_flags & MS_RDONLY) {
760 if (nilfs_test_opt(sbi, SNAPSHOT)) {
Zhu Yanhai43be0ec2009-08-12 14:17:59 +0800761 down_read(&nilfs->ns_segctor_sem);
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700762 err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,
763 sbi->s_snapshot_cno);
Zhu Yanhai43be0ec2009-08-12 14:17:59 +0800764 up_read(&nilfs->ns_segctor_sem);
765 if (err < 0) {
766 if (err == -ENOENT)
767 err = -EINVAL;
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700768 goto failed_sbi;
Zhu Yanhai43be0ec2009-08-12 14:17:59 +0800769 }
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700770 if (!err) {
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700771 printk(KERN_ERR
772 "NILFS: The specified checkpoint is "
773 "not a snapshot "
774 "(checkpoint number=%llu).\n",
775 (unsigned long long)sbi->s_snapshot_cno);
776 err = -EINVAL;
777 goto failed_sbi;
778 }
779 cno = sbi->s_snapshot_cno;
780 } else
781 /* Read-only mount */
782 sbi->s_snapshot_cno = cno;
783 }
784
785 err = nilfs_attach_checkpoint(sbi, cno);
786 if (err) {
787 printk(KERN_ERR "NILFS: error loading a checkpoint"
788 " (checkpoint number=%llu).\n", (unsigned long long)cno);
789 goto failed_sbi;
790 }
791
792 if (!(sb->s_flags & MS_RDONLY)) {
Ryusuke Konishicece5522009-04-06 19:01:58 -0700793 err = nilfs_attach_segment_constructor(sbi);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700794 if (err)
795 goto failed_checkpoint;
796 }
797
798 root = nilfs_iget(sb, NILFS_ROOT_INO);
799 if (IS_ERR(root)) {
800 printk(KERN_ERR "NILFS: get root inode failed\n");
801 err = PTR_ERR(root);
802 goto failed_segctor;
803 }
804 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
805 iput(root);
806 printk(KERN_ERR "NILFS: corrupt root inode.\n");
807 err = -EINVAL;
808 goto failed_segctor;
809 }
810 sb->s_root = d_alloc_root(root);
811 if (!sb->s_root) {
812 iput(root);
813 printk(KERN_ERR "NILFS: get root dentry failed\n");
814 err = -ENOMEM;
815 goto failed_segctor;
816 }
817
818 if (!(sb->s_flags & MS_RDONLY)) {
819 down_write(&nilfs->ns_sem);
820 nilfs_setup_super(sbi);
821 up_write(&nilfs->ns_sem);
822 }
823
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900824 down_write(&nilfs->ns_super_sem);
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900825 if (!nilfs_test_opt(sbi, SNAPSHOT))
826 nilfs->ns_current = sbi;
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900827 up_write(&nilfs->ns_super_sem);
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900828
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700829 return 0;
830
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700831 failed_segctor:
832 nilfs_detach_segment_constructor(sbi);
833
834 failed_checkpoint:
835 nilfs_detach_checkpoint(sbi);
836
837 failed_sbi:
838 put_nilfs(nilfs);
839 sb->s_fs_info = NULL;
Ryusuke Konishi6dd47402009-06-08 01:39:31 +0900840 nilfs_put_sbinfo(sbi);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700841 return err;
842}
843
844static int nilfs_remount(struct super_block *sb, int *flags, char *data)
845{
846 struct nilfs_sb_info *sbi = NILFS_SB(sb);
847 struct nilfs_super_block *sbp;
848 struct the_nilfs *nilfs = sbi->s_nilfs;
849 unsigned long old_sb_flags;
850 struct nilfs_mount_options old_opts;
851 int err;
852
Alessio Igor Bogani337eb002009-05-12 15:10:54 +0200853 lock_kernel();
854
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900855 down_write(&nilfs->ns_super_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700856 old_sb_flags = sb->s_flags;
857 old_opts.mount_opt = sbi->s_mount_opt;
858 old_opts.snapshot_cno = sbi->s_snapshot_cno;
859
860 if (!parse_options(data, sb)) {
861 err = -EINVAL;
862 goto restore_opts;
863 }
864 sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
865
866 if ((*flags & MS_RDONLY) &&
867 sbi->s_snapshot_cno != old_opts.snapshot_cno) {
868 printk(KERN_WARNING "NILFS (device %s): couldn't "
Ryusuke Konishic91cea12010-03-14 04:01:27 +0900869 "remount to a different snapshot.\n",
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700870 sb->s_id);
871 err = -EINVAL;
872 goto restore_opts;
873 }
874
Ryusuke Konishi02345762009-11-20 03:28:01 +0900875 if (!nilfs_valid_fs(nilfs)) {
876 printk(KERN_WARNING "NILFS (device %s): couldn't "
877 "remount because the filesystem is in an "
878 "incomplete recovery state.\n", sb->s_id);
879 err = -EINVAL;
880 goto restore_opts;
881 }
882
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700883 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
884 goto out;
885 if (*flags & MS_RDONLY) {
886 /* Shutting down the segment constructor */
887 nilfs_detach_segment_constructor(sbi);
888 sb->s_flags |= MS_RDONLY;
889
890 sbi->s_snapshot_cno = nilfs_last_cno(nilfs);
891 /* nilfs_set_opt(sbi, SNAPSHOT); */
892
893 /*
894 * Remounting a valid RW partition RDONLY, so set
895 * the RDONLY flag and then mark the partition as valid again.
896 */
897 down_write(&nilfs->ns_sem);
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700898 sbp = nilfs->ns_sbp[0];
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700899 if (!(sbp->s_state & le16_to_cpu(NILFS_VALID_FS)) &&
900 (nilfs->ns_mount_state & NILFS_VALID_FS))
901 sbp->s_state = cpu_to_le16(nilfs->ns_mount_state);
902 sbp->s_mtime = cpu_to_le64(get_seconds());
Ryusuke Konishie339ad32009-04-06 19:01:59 -0700903 nilfs_commit_super(sbi, 1);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700904 up_write(&nilfs->ns_sem);
905 } else {
906 /*
907 * Mounting a RDONLY partition read-write, so reread and
908 * store the current valid flag. (It may have been changed
909 * by fsck since we originally mounted the partition.)
910 */
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900911 if (nilfs->ns_current && nilfs->ns_current != sbi) {
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700912 printk(KERN_WARNING "NILFS (device %s): couldn't "
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +0900913 "remount because an RW-mount exists.\n",
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700914 sb->s_id);
915 err = -EBUSY;
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900916 goto restore_opts;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700917 }
918 if (sbi->s_snapshot_cno != nilfs_last_cno(nilfs)) {
919 printk(KERN_WARNING "NILFS (device %s): couldn't "
920 "remount because the current RO-mount is not "
921 "the latest one.\n",
922 sb->s_id);
923 err = -EINVAL;
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900924 goto restore_opts;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700925 }
926 sb->s_flags &= ~MS_RDONLY;
927 nilfs_clear_opt(sbi, SNAPSHOT);
928 sbi->s_snapshot_cno = 0;
929
Ryusuke Konishicece5522009-04-06 19:01:58 -0700930 err = nilfs_attach_segment_constructor(sbi);
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700931 if (err)
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900932 goto restore_opts;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700933
934 down_write(&nilfs->ns_sem);
935 nilfs_setup_super(sbi);
936 up_write(&nilfs->ns_sem);
937
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900938 nilfs->ns_current = sbi;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700939 }
940 out:
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900941 up_write(&nilfs->ns_super_sem);
Alessio Igor Bogani337eb002009-05-12 15:10:54 +0200942 unlock_kernel();
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700943 return 0;
944
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700945 restore_opts:
946 sb->s_flags = old_sb_flags;
947 sbi->s_mount_opt = old_opts.mount_opt;
948 sbi->s_snapshot_cno = old_opts.snapshot_cno;
Ryusuke Konishie59399d2009-06-08 01:39:32 +0900949 up_write(&nilfs->ns_super_sem);
Alessio Igor Bogani337eb002009-05-12 15:10:54 +0200950 unlock_kernel();
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700951 return err;
952}
953
954struct nilfs_super_data {
955 struct block_device *bdev;
Ryusuke Konishi6dd47402009-06-08 01:39:31 +0900956 struct nilfs_sb_info *sbi;
Ryusuke Konishi783f6182009-04-06 19:01:35 -0700957 __u64 cno;
958 int flags;
959};
960
961/**
962 * nilfs_identify - pre-read mount options needed to identify mount instance
963 * @data: mount options
964 * @sd: nilfs_super_data
965 */
966static int nilfs_identify(char *data, struct nilfs_super_data *sd)
967{
968 char *p, *options = data;
969 substring_t args[MAX_OPT_ARGS];
970 int option, token;
971 int ret = 0;
972
973 do {
974 p = strsep(&options, ",");
975 if (p != NULL && *p) {
976 token = match_token(p, tokens, args);
977 if (token == Opt_snapshot) {
978 if (!(sd->flags & MS_RDONLY))
979 ret++;
980 else {
981 ret = match_int(&args[0], &option);
982 if (!ret) {
983 if (option > 0)
984 sd->cno = option;
985 else
986 ret++;
987 }
988 }
989 }
990 if (ret)
991 printk(KERN_ERR
992 "NILFS: invalid mount option: %s\n", p);
993 }
994 if (!options)
995 break;
996 BUG_ON(options == data);
997 *(options - 1) = ',';
998 } while (!ret);
999 return ret;
1000}
1001
1002static int nilfs_set_bdev_super(struct super_block *s, void *data)
1003{
1004 struct nilfs_super_data *sd = data;
1005
1006 s->s_bdev = sd->bdev;
1007 s->s_dev = s->s_bdev->bd_dev;
1008 return 0;
1009}
1010
1011static int nilfs_test_bdev_super(struct super_block *s, void *data)
1012{
1013 struct nilfs_super_data *sd = data;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001014
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001015 return sd->sbi && s->s_fs_info == (void *)sd->sbi;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001016}
1017
1018static int
1019nilfs_get_sb(struct file_system_type *fs_type, int flags,
1020 const char *dev_name, void *data, struct vfsmount *mnt)
1021{
1022 struct nilfs_super_data sd;
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001023 struct super_block *s;
1024 struct the_nilfs *nilfs;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001025 int err, need_to_close = 1;
1026
1027 sd.bdev = open_bdev_exclusive(dev_name, flags, fs_type);
1028 if (IS_ERR(sd.bdev))
1029 return PTR_ERR(sd.bdev);
1030
1031 /*
1032 * To get mount instance using sget() vfs-routine, NILFS needs
1033 * much more information than normal filesystems to identify mount
1034 * instance. For snapshot mounts, not only a mount type (ro-mount
1035 * or rw-mount) but also a checkpoint number is required.
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001036 */
1037 sd.cno = 0;
1038 sd.flags = flags;
1039 if (nilfs_identify((char *)data, &sd)) {
1040 err = -EINVAL;
1041 goto failed;
1042 }
1043
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001044 nilfs = find_or_create_nilfs(sd.bdev);
1045 if (!nilfs) {
1046 err = -ENOMEM;
1047 goto failed;
1048 }
1049
Ryusuke Konishiaa7dfb82009-06-08 01:39:33 +09001050 mutex_lock(&nilfs->ns_mount_mutex);
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +09001051
1052 if (!sd.cno) {
1053 /*
1054 * Check if an exclusive mount exists or not.
1055 * Snapshot mounts coexist with a current mount
1056 * (i.e. rw-mount or ro-mount), whereas rw-mount and
1057 * ro-mount are mutually exclusive.
1058 */
Ryusuke Konishie59399d2009-06-08 01:39:32 +09001059 down_read(&nilfs->ns_super_sem);
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +09001060 if (nilfs->ns_current &&
1061 ((nilfs->ns_current->s_super->s_flags ^ flags)
1062 & MS_RDONLY)) {
Ryusuke Konishie59399d2009-06-08 01:39:32 +09001063 up_read(&nilfs->ns_super_sem);
Ryusuke Konishi3f82ff52009-06-08 01:39:30 +09001064 err = -EBUSY;
1065 goto failed_unlock;
1066 }
Ryusuke Konishie59399d2009-06-08 01:39:32 +09001067 up_read(&nilfs->ns_super_sem);
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001068 }
1069
1070 /*
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001071 * Find existing nilfs_sb_info struct
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001072 */
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001073 sd.sbi = nilfs_find_sbinfo(nilfs, !(flags & MS_RDONLY), sd.cno);
1074
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001075 /*
1076 * Get super block instance holding the nilfs_sb_info struct.
1077 * A new instance is allocated if no existing mount is present or
1078 * existing instance has been unmounted.
1079 */
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001080 s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, &sd);
Ryusuke Konishi6dd47402009-06-08 01:39:31 +09001081 if (sd.sbi)
1082 nilfs_put_sbinfo(sd.sbi);
1083
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001084 if (IS_ERR(s)) {
1085 err = PTR_ERR(s);
1086 goto failed_unlock;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001087 }
1088
1089 if (!s->s_root) {
1090 char b[BDEVNAME_SIZE];
1091
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001092 /* New superblock instance created */
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001093 s->s_flags = flags;
1094 strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
1095 sb_set_blocksize(s, block_size(sd.bdev));
1096
1097 err = nilfs_fill_super(s, data, flags & MS_VERBOSE, nilfs);
1098 if (err)
1099 goto cancel_new;
1100
1101 s->s_flags |= MS_ACTIVE;
1102 need_to_close = 0;
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001103 }
1104
Ryusuke Konishiaa7dfb82009-06-08 01:39:33 +09001105 mutex_unlock(&nilfs->ns_mount_mutex);
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001106 put_nilfs(nilfs);
1107 if (need_to_close)
1108 close_bdev_exclusive(sd.bdev, flags);
1109 simple_set_mnt(mnt, s);
1110 return 0;
1111
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001112 failed_unlock:
Ryusuke Konishiaa7dfb82009-06-08 01:39:33 +09001113 mutex_unlock(&nilfs->ns_mount_mutex);
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001114 put_nilfs(nilfs);
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001115 failed:
1116 close_bdev_exclusive(sd.bdev, flags);
1117
1118 return err;
1119
1120 cancel_new:
1121 /* Abandoning the newly allocated superblock */
Ryusuke Konishiaa7dfb82009-06-08 01:39:33 +09001122 mutex_unlock(&nilfs->ns_mount_mutex);
Ryusuke Konishi33c8e572009-06-08 01:39:29 +09001123 put_nilfs(nilfs);
Al Viroa95161a2009-08-09 00:52:02 +04001124 deactivate_locked_super(s);
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001125 /*
1126 * deactivate_super() invokes close_bdev_exclusive().
1127 * We must finish all post-cleaning before this call;
Ryusuke Konishiaa7dfb82009-06-08 01:39:33 +09001128 * put_nilfs() needs the block device.
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001129 */
1130 return err;
1131}
1132
Ryusuke Konishi783f6182009-04-06 19:01:35 -07001133struct file_system_type nilfs_fs_type = {
1134 .owner = THIS_MODULE,
1135 .name = "nilfs2",
1136 .get_sb = nilfs_get_sb,
1137 .kill_sb = kill_block_super,
1138 .fs_flags = FS_REQUIRES_DEV,
1139};
1140
1141static int __init init_nilfs_fs(void)
1142{
1143 int err;
1144
1145 err = nilfs_init_inode_cache();
1146 if (err)
1147 goto failed;
1148
1149 err = nilfs_init_transaction_cache();
1150 if (err)
1151 goto failed_inode_cache;
1152
1153 err = nilfs_init_segbuf_cache();
1154 if (err)
1155 goto failed_transaction_cache;
1156
1157 err = nilfs_btree_path_cache_init();
1158 if (err)
1159 goto failed_segbuf_cache;
1160
1161 err = register_filesystem(&nilfs_fs_type);
1162 if (err)
1163 goto failed_btree_path_cache;
1164
1165 return 0;
1166
1167 failed_btree_path_cache:
1168 nilfs_btree_path_cache_destroy();
1169
1170 failed_segbuf_cache:
1171 nilfs_destroy_segbuf_cache();
1172
1173 failed_transaction_cache:
1174 nilfs_destroy_transaction_cache();
1175
1176 failed_inode_cache:
1177 nilfs_destroy_inode_cache();
1178
1179 failed:
1180 return err;
1181}
1182
1183static void __exit exit_nilfs_fs(void)
1184{
1185 nilfs_destroy_segbuf_cache();
1186 nilfs_destroy_transaction_cache();
1187 nilfs_destroy_inode_cache();
1188 nilfs_btree_path_cache_destroy();
1189 unregister_filesystem(&nilfs_fs_type);
1190}
1191
1192module_init(init_nilfs_fs)
1193module_exit(exit_nilfs_fs)