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783f6184 RK |
1 | /* |
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> | |
b58a285b JS |
53 | #include <linux/seq_file.h> |
54 | #include <linux/mount.h> | |
783f6184 RK |
55 | #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 | ||
65 | MODULE_AUTHOR("NTT Corp."); | |
66 | MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem " | |
67 | "(NILFS)"); | |
783f6184 RK |
68 | MODULE_LICENSE("GPL"); |
69 | ||
8c85e125 | 70 | static void nilfs_write_super(struct super_block *sb); |
783f6184 | 71 | static int nilfs_remount(struct super_block *sb, int *flags, char *data); |
783f6184 RK |
72 | |
73 | /** | |
74 | * nilfs_error() - report failure condition on a filesystem | |
75 | * | |
76 | * nilfs_error() sets an ERROR_FS flag on the superblock as well as | |
77 | * reporting an error message. It should be called when NILFS detects | |
78 | * incoherences or defects of meta data on disk. As for sustainable | |
79 | * errors such as a single-shot I/O error, nilfs_warning() or the printk() | |
80 | * function should be used instead. | |
81 | * | |
82 | * The segment constructor must not call this function because it can | |
83 | * kill itself. | |
84 | */ | |
85 | void nilfs_error(struct super_block *sb, const char *function, | |
86 | const char *fmt, ...) | |
87 | { | |
88 | struct nilfs_sb_info *sbi = NILFS_SB(sb); | |
89 | va_list args; | |
90 | ||
91 | va_start(args, fmt); | |
92 | printk(KERN_CRIT "NILFS error (device %s): %s: ", sb->s_id, function); | |
93 | vprintk(fmt, args); | |
94 | printk("\n"); | |
95 | va_end(args); | |
96 | ||
97 | if (!(sb->s_flags & MS_RDONLY)) { | |
98 | struct the_nilfs *nilfs = sbi->s_nilfs; | |
99 | ||
100 | if (!nilfs_test_opt(sbi, ERRORS_CONT)) | |
101 | nilfs_detach_segment_constructor(sbi); | |
102 | ||
103 | down_write(&nilfs->ns_sem); | |
104 | if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) { | |
105 | nilfs->ns_mount_state |= NILFS_ERROR_FS; | |
e339ad31 RK |
106 | nilfs->ns_sbp[0]->s_state |= |
107 | cpu_to_le16(NILFS_ERROR_FS); | |
108 | nilfs_commit_super(sbi, 1); | |
783f6184 RK |
109 | } |
110 | up_write(&nilfs->ns_sem); | |
111 | ||
112 | if (nilfs_test_opt(sbi, ERRORS_RO)) { | |
113 | printk(KERN_CRIT "Remounting filesystem read-only\n"); | |
114 | sb->s_flags |= MS_RDONLY; | |
115 | } | |
116 | } | |
117 | ||
118 | if (nilfs_test_opt(sbi, ERRORS_PANIC)) | |
119 | panic("NILFS (device %s): panic forced after error\n", | |
120 | sb->s_id); | |
121 | } | |
122 | ||
123 | void nilfs_warning(struct super_block *sb, const char *function, | |
124 | const char *fmt, ...) | |
125 | { | |
126 | va_list args; | |
127 | ||
128 | va_start(args, fmt); | |
129 | printk(KERN_WARNING "NILFS warning (device %s): %s: ", | |
130 | sb->s_id, function); | |
131 | vprintk(fmt, args); | |
132 | printk("\n"); | |
133 | va_end(args); | |
134 | } | |
135 | ||
136 | static struct kmem_cache *nilfs_inode_cachep; | |
137 | ||
a53b4751 | 138 | struct inode *nilfs_alloc_inode_common(struct the_nilfs *nilfs) |
783f6184 RK |
139 | { |
140 | struct nilfs_inode_info *ii; | |
141 | ||
142 | ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS); | |
143 | if (!ii) | |
144 | return NULL; | |
145 | ii->i_bh = NULL; | |
146 | ii->i_state = 0; | |
147 | ii->vfs_inode.i_version = 1; | |
a53b4751 | 148 | nilfs_btnode_cache_init(&ii->i_btnode_cache, nilfs->ns_bdi); |
783f6184 RK |
149 | return &ii->vfs_inode; |
150 | } | |
151 | ||
a53b4751 RK |
152 | struct inode *nilfs_alloc_inode(struct super_block *sb) |
153 | { | |
154 | return nilfs_alloc_inode_common(NILFS_SB(sb)->s_nilfs); | |
155 | } | |
156 | ||
783f6184 RK |
157 | void nilfs_destroy_inode(struct inode *inode) |
158 | { | |
159 | kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode)); | |
160 | } | |
161 | ||
162 | static void init_once(void *obj) | |
163 | { | |
164 | struct nilfs_inode_info *ii = obj; | |
165 | ||
166 | INIT_LIST_HEAD(&ii->i_dirty); | |
167 | #ifdef CONFIG_NILFS_XATTR | |
168 | init_rwsem(&ii->xattr_sem); | |
169 | #endif | |
170 | nilfs_btnode_cache_init_once(&ii->i_btnode_cache); | |
171 | ii->i_bmap = (struct nilfs_bmap *)&ii->i_bmap_union; | |
172 | inode_init_once(&ii->vfs_inode); | |
173 | } | |
174 | ||
175 | static int nilfs_init_inode_cache(void) | |
176 | { | |
177 | nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache", | |
178 | sizeof(struct nilfs_inode_info), | |
179 | 0, SLAB_RECLAIM_ACCOUNT, | |
180 | init_once); | |
181 | ||
182 | return (nilfs_inode_cachep == NULL) ? -ENOMEM : 0; | |
183 | } | |
184 | ||
185 | static inline void nilfs_destroy_inode_cache(void) | |
186 | { | |
187 | kmem_cache_destroy(nilfs_inode_cachep); | |
188 | } | |
189 | ||
190 | static void nilfs_clear_inode(struct inode *inode) | |
191 | { | |
192 | struct nilfs_inode_info *ii = NILFS_I(inode); | |
783f6184 | 193 | |
783f6184 RK |
194 | /* |
195 | * Free resources allocated in nilfs_read_inode(), here. | |
196 | */ | |
a2e7d2df | 197 | BUG_ON(!list_empty(&ii->i_dirty)); |
783f6184 RK |
198 | brelse(ii->i_bh); |
199 | ii->i_bh = NULL; | |
783f6184 RK |
200 | |
201 | if (test_bit(NILFS_I_BMAP, &ii->i_state)) | |
202 | nilfs_bmap_clear(ii->i_bmap); | |
203 | ||
204 | nilfs_btnode_cache_clear(&ii->i_btnode_cache); | |
783f6184 RK |
205 | } |
206 | ||
e339ad31 | 207 | static int nilfs_sync_super(struct nilfs_sb_info *sbi, int dupsb) |
783f6184 RK |
208 | { |
209 | struct the_nilfs *nilfs = sbi->s_nilfs; | |
210 | int err; | |
211 | int barrier_done = 0; | |
212 | ||
213 | if (nilfs_test_opt(sbi, BARRIER)) { | |
e339ad31 | 214 | set_buffer_ordered(nilfs->ns_sbh[0]); |
783f6184 RK |
215 | barrier_done = 1; |
216 | } | |
217 | retry: | |
e339ad31 RK |
218 | set_buffer_dirty(nilfs->ns_sbh[0]); |
219 | err = sync_dirty_buffer(nilfs->ns_sbh[0]); | |
783f6184 RK |
220 | if (err == -EOPNOTSUPP && barrier_done) { |
221 | nilfs_warning(sbi->s_super, __func__, | |
222 | "barrier-based sync failed. " | |
223 | "disabling barriers\n"); | |
224 | nilfs_clear_opt(sbi, BARRIER); | |
225 | barrier_done = 0; | |
e339ad31 | 226 | clear_buffer_ordered(nilfs->ns_sbh[0]); |
783f6184 RK |
227 | goto retry; |
228 | } | |
e339ad31 | 229 | if (unlikely(err)) { |
783f6184 RK |
230 | printk(KERN_ERR |
231 | "NILFS: unable to write superblock (err=%d)\n", err); | |
e339ad31 RK |
232 | if (err == -EIO && nilfs->ns_sbh[1]) { |
233 | nilfs_fall_back_super_block(nilfs); | |
234 | goto retry; | |
235 | } | |
236 | } else { | |
237 | struct nilfs_super_block *sbp = nilfs->ns_sbp[0]; | |
238 | ||
239 | /* | |
240 | * The latest segment becomes trailable from the position | |
241 | * written in superblock. | |
242 | */ | |
783f6184 | 243 | clear_nilfs_discontinued(nilfs); |
e339ad31 RK |
244 | |
245 | /* update GC protection for recent segments */ | |
246 | if (nilfs->ns_sbh[1]) { | |
247 | sbp = NULL; | |
248 | if (dupsb) { | |
249 | set_buffer_dirty(nilfs->ns_sbh[1]); | |
250 | if (!sync_dirty_buffer(nilfs->ns_sbh[1])) | |
251 | sbp = nilfs->ns_sbp[1]; | |
252 | } | |
253 | } | |
254 | if (sbp) { | |
255 | spin_lock(&nilfs->ns_last_segment_lock); | |
256 | nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq); | |
257 | spin_unlock(&nilfs->ns_last_segment_lock); | |
258 | } | |
783f6184 RK |
259 | } |
260 | ||
261 | return err; | |
262 | } | |
263 | ||
e339ad31 | 264 | int nilfs_commit_super(struct nilfs_sb_info *sbi, int dupsb) |
783f6184 RK |
265 | { |
266 | struct the_nilfs *nilfs = sbi->s_nilfs; | |
e339ad31 | 267 | struct nilfs_super_block **sbp = nilfs->ns_sbp; |
783f6184 | 268 | sector_t nfreeblocks; |
e339ad31 | 269 | time_t t; |
783f6184 RK |
270 | int err; |
271 | ||
272 | /* nilfs->sem must be locked by the caller. */ | |
e339ad31 RK |
273 | if (sbp[0]->s_magic != NILFS_SUPER_MAGIC) { |
274 | if (sbp[1] && sbp[1]->s_magic == NILFS_SUPER_MAGIC) | |
275 | nilfs_swap_super_block(nilfs); | |
276 | else { | |
277 | printk(KERN_CRIT "NILFS: superblock broke on dev %s\n", | |
278 | sbi->s_super->s_id); | |
279 | return -EIO; | |
280 | } | |
281 | } | |
783f6184 RK |
282 | err = nilfs_count_free_blocks(nilfs, &nfreeblocks); |
283 | if (unlikely(err)) { | |
284 | printk(KERN_ERR "NILFS: failed to count free blocks\n"); | |
285 | return err; | |
286 | } | |
e339ad31 RK |
287 | spin_lock(&nilfs->ns_last_segment_lock); |
288 | sbp[0]->s_last_seq = cpu_to_le64(nilfs->ns_last_seq); | |
289 | sbp[0]->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg); | |
290 | sbp[0]->s_last_cno = cpu_to_le64(nilfs->ns_last_cno); | |
291 | spin_unlock(&nilfs->ns_last_segment_lock); | |
292 | ||
293 | t = get_seconds(); | |
294 | nilfs->ns_sbwtime[0] = t; | |
295 | sbp[0]->s_free_blocks_count = cpu_to_le64(nfreeblocks); | |
296 | sbp[0]->s_wtime = cpu_to_le64(t); | |
297 | sbp[0]->s_sum = 0; | |
298 | sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, | |
299 | (unsigned char *)sbp[0], | |
300 | nilfs->ns_sbsize)); | |
301 | if (dupsb && sbp[1]) { | |
302 | memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); | |
303 | nilfs->ns_sbwtime[1] = t; | |
304 | } | |
783f6184 | 305 | sbi->s_super->s_dirt = 0; |
e339ad31 | 306 | return nilfs_sync_super(sbi, dupsb); |
783f6184 RK |
307 | } |
308 | ||
309 | static void nilfs_put_super(struct super_block *sb) | |
310 | { | |
311 | struct nilfs_sb_info *sbi = NILFS_SB(sb); | |
312 | struct the_nilfs *nilfs = sbi->s_nilfs; | |
313 | ||
6cfd0148 CH |
314 | lock_kernel(); |
315 | ||
783f6184 RK |
316 | nilfs_detach_segment_constructor(sbi); |
317 | ||
318 | if (!(sb->s_flags & MS_RDONLY)) { | |
319 | down_write(&nilfs->ns_sem); | |
e339ad31 RK |
320 | nilfs->ns_sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state); |
321 | nilfs_commit_super(sbi, 1); | |
783f6184 RK |
322 | up_write(&nilfs->ns_sem); |
323 | } | |
e59399d0 | 324 | down_write(&nilfs->ns_super_sem); |
3f82ff55 RK |
325 | if (nilfs->ns_current == sbi) |
326 | nilfs->ns_current = NULL; | |
e59399d0 | 327 | up_write(&nilfs->ns_super_sem); |
783f6184 RK |
328 | |
329 | nilfs_detach_checkpoint(sbi); | |
330 | put_nilfs(sbi->s_nilfs); | |
331 | sbi->s_super = NULL; | |
332 | sb->s_fs_info = NULL; | |
6dd47406 | 333 | nilfs_put_sbinfo(sbi); |
6cfd0148 CH |
334 | |
335 | unlock_kernel(); | |
783f6184 RK |
336 | } |
337 | ||
338 | /** | |
339 | * nilfs_write_super - write super block(s) of NILFS | |
340 | * @sb: super_block | |
341 | * | |
342 | * nilfs_write_super() gets a fs-dependent lock, writes super block(s), and | |
343 | * clears s_dirt. This function is called in the section protected by | |
344 | * lock_super(). | |
345 | * | |
346 | * The s_dirt flag is managed by each filesystem and we protect it by ns_sem | |
347 | * of the struct the_nilfs. Lock order must be as follows: | |
348 | * | |
349 | * 1. lock_super() | |
350 | * 2. down_write(&nilfs->ns_sem) | |
351 | * | |
352 | * Inside NILFS, locking ns_sem is enough to protect s_dirt and the buffer | |
e339ad31 | 353 | * of the super block (nilfs->ns_sbp[]). |
783f6184 RK |
354 | * |
355 | * In most cases, VFS functions call lock_super() before calling these | |
356 | * methods. So we must be careful not to bring on deadlocks when using | |
357 | * lock_super(); see generic_shutdown_super(), write_super(), and so on. | |
358 | * | |
359 | * Note that order of lock_kernel() and lock_super() depends on contexts | |
360 | * of VFS. We should also note that lock_kernel() can be used in its | |
361 | * protective section and only the outermost one has an effect. | |
362 | */ | |
363 | static void nilfs_write_super(struct super_block *sb) | |
364 | { | |
365 | struct nilfs_sb_info *sbi = NILFS_SB(sb); | |
366 | struct the_nilfs *nilfs = sbi->s_nilfs; | |
367 | ||
368 | down_write(&nilfs->ns_sem); | |
e339ad31 RK |
369 | if (!(sb->s_flags & MS_RDONLY)) { |
370 | struct nilfs_super_block **sbp = nilfs->ns_sbp; | |
371 | u64 t = get_seconds(); | |
372 | int dupsb; | |
373 | ||
374 | if (!nilfs_discontinued(nilfs) && t >= nilfs->ns_sbwtime[0] && | |
375 | t < nilfs->ns_sbwtime[0] + NILFS_SB_FREQ) { | |
376 | up_write(&nilfs->ns_sem); | |
377 | return; | |
378 | } | |
379 | dupsb = sbp[1] && t > nilfs->ns_sbwtime[1] + NILFS_ALTSB_FREQ; | |
380 | nilfs_commit_super(sbi, dupsb); | |
381 | } | |
783f6184 RK |
382 | sb->s_dirt = 0; |
383 | up_write(&nilfs->ns_sem); | |
384 | } | |
385 | ||
386 | static int nilfs_sync_fs(struct super_block *sb, int wait) | |
387 | { | |
388 | int err = 0; | |
389 | ||
d731e063 CH |
390 | nilfs_write_super(sb); |
391 | ||
783f6184 RK |
392 | /* This function is called when super block should be written back */ |
393 | if (wait) | |
394 | err = nilfs_construct_segment(sb); | |
395 | return err; | |
396 | } | |
397 | ||
398 | int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno) | |
399 | { | |
400 | struct the_nilfs *nilfs = sbi->s_nilfs; | |
401 | struct nilfs_checkpoint *raw_cp; | |
402 | struct buffer_head *bh_cp; | |
403 | int err; | |
404 | ||
e59399d0 | 405 | down_write(&nilfs->ns_super_sem); |
783f6184 | 406 | list_add(&sbi->s_list, &nilfs->ns_supers); |
e59399d0 | 407 | up_write(&nilfs->ns_super_sem); |
783f6184 RK |
408 | |
409 | sbi->s_ifile = nilfs_mdt_new( | |
410 | nilfs, sbi->s_super, NILFS_IFILE_INO, NILFS_IFILE_GFP); | |
411 | if (!sbi->s_ifile) | |
412 | return -ENOMEM; | |
413 | ||
414 | err = nilfs_palloc_init_blockgroup(sbi->s_ifile, nilfs->ns_inode_size); | |
415 | if (unlikely(err)) | |
416 | goto failed; | |
417 | ||
1154ecbd | 418 | down_read(&nilfs->ns_segctor_sem); |
783f6184 RK |
419 | err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp, |
420 | &bh_cp); | |
1154ecbd | 421 | up_read(&nilfs->ns_segctor_sem); |
783f6184 RK |
422 | if (unlikely(err)) { |
423 | if (err == -ENOENT || err == -EINVAL) { | |
424 | printk(KERN_ERR | |
425 | "NILFS: Invalid checkpoint " | |
426 | "(checkpoint number=%llu)\n", | |
427 | (unsigned long long)cno); | |
428 | err = -EINVAL; | |
429 | } | |
430 | goto failed; | |
431 | } | |
432 | err = nilfs_read_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode); | |
433 | if (unlikely(err)) | |
434 | goto failed_bh; | |
435 | atomic_set(&sbi->s_inodes_count, le64_to_cpu(raw_cp->cp_inodes_count)); | |
436 | atomic_set(&sbi->s_blocks_count, le64_to_cpu(raw_cp->cp_blocks_count)); | |
437 | ||
438 | nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); | |
439 | return 0; | |
440 | ||
441 | failed_bh: | |
442 | nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); | |
443 | failed: | |
444 | nilfs_mdt_destroy(sbi->s_ifile); | |
445 | sbi->s_ifile = NULL; | |
446 | ||
e59399d0 | 447 | down_write(&nilfs->ns_super_sem); |
783f6184 | 448 | list_del_init(&sbi->s_list); |
e59399d0 | 449 | up_write(&nilfs->ns_super_sem); |
783f6184 RK |
450 | |
451 | return err; | |
452 | } | |
453 | ||
454 | void nilfs_detach_checkpoint(struct nilfs_sb_info *sbi) | |
455 | { | |
456 | struct the_nilfs *nilfs = sbi->s_nilfs; | |
457 | ||
458 | nilfs_mdt_clear(sbi->s_ifile); | |
459 | nilfs_mdt_destroy(sbi->s_ifile); | |
460 | sbi->s_ifile = NULL; | |
e59399d0 | 461 | down_write(&nilfs->ns_super_sem); |
783f6184 | 462 | list_del_init(&sbi->s_list); |
e59399d0 | 463 | up_write(&nilfs->ns_super_sem); |
783f6184 RK |
464 | } |
465 | ||
466 | static int nilfs_mark_recovery_complete(struct nilfs_sb_info *sbi) | |
467 | { | |
468 | struct the_nilfs *nilfs = sbi->s_nilfs; | |
469 | int err = 0; | |
470 | ||
471 | down_write(&nilfs->ns_sem); | |
472 | if (!(nilfs->ns_mount_state & NILFS_VALID_FS)) { | |
473 | nilfs->ns_mount_state |= NILFS_VALID_FS; | |
e339ad31 | 474 | err = nilfs_commit_super(sbi, 1); |
783f6184 RK |
475 | if (likely(!err)) |
476 | printk(KERN_INFO "NILFS: recovery complete.\n"); | |
477 | } | |
478 | up_write(&nilfs->ns_sem); | |
479 | return err; | |
480 | } | |
481 | ||
482 | static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf) | |
483 | { | |
484 | struct super_block *sb = dentry->d_sb; | |
485 | struct nilfs_sb_info *sbi = NILFS_SB(sb); | |
c306af23 RK |
486 | struct the_nilfs *nilfs = sbi->s_nilfs; |
487 | u64 id = huge_encode_dev(sb->s_bdev->bd_dev); | |
783f6184 RK |
488 | unsigned long long blocks; |
489 | unsigned long overhead; | |
490 | unsigned long nrsvblocks; | |
491 | sector_t nfreeblocks; | |
783f6184 RK |
492 | int err; |
493 | ||
494 | /* | |
495 | * Compute all of the segment blocks | |
496 | * | |
497 | * The blocks before first segment and after last segment | |
498 | * are excluded. | |
499 | */ | |
500 | blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments | |
501 | - nilfs->ns_first_data_block; | |
502 | nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment; | |
503 | ||
504 | /* | |
505 | * Compute the overhead | |
506 | * | |
507 | * When distributing meta data blocks outside semgent structure, | |
508 | * We must count them as the overhead. | |
509 | */ | |
510 | overhead = 0; | |
511 | ||
512 | err = nilfs_count_free_blocks(nilfs, &nfreeblocks); | |
513 | if (unlikely(err)) | |
514 | return err; | |
515 | ||
516 | buf->f_type = NILFS_SUPER_MAGIC; | |
517 | buf->f_bsize = sb->s_blocksize; | |
518 | buf->f_blocks = blocks - overhead; | |
519 | buf->f_bfree = nfreeblocks; | |
520 | buf->f_bavail = (buf->f_bfree >= nrsvblocks) ? | |
521 | (buf->f_bfree - nrsvblocks) : 0; | |
522 | buf->f_files = atomic_read(&sbi->s_inodes_count); | |
523 | buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */ | |
524 | buf->f_namelen = NILFS_NAME_LEN; | |
c306af23 RK |
525 | buf->f_fsid.val[0] = (u32)id; |
526 | buf->f_fsid.val[1] = (u32)(id >> 32); | |
527 | ||
783f6184 RK |
528 | return 0; |
529 | } | |
530 | ||
b58a285b JS |
531 | static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs) |
532 | { | |
533 | struct super_block *sb = vfs->mnt_sb; | |
534 | struct nilfs_sb_info *sbi = NILFS_SB(sb); | |
535 | ||
536 | if (!nilfs_test_opt(sbi, BARRIER)) | |
537 | seq_printf(seq, ",barrier=off"); | |
538 | if (nilfs_test_opt(sbi, SNAPSHOT)) | |
539 | seq_printf(seq, ",cp=%llu", | |
540 | (unsigned long long int)sbi->s_snapshot_cno); | |
541 | if (nilfs_test_opt(sbi, ERRORS_RO)) | |
542 | seq_printf(seq, ",errors=remount-ro"); | |
543 | if (nilfs_test_opt(sbi, ERRORS_PANIC)) | |
544 | seq_printf(seq, ",errors=panic"); | |
545 | if (nilfs_test_opt(sbi, STRICT_ORDER)) | |
546 | seq_printf(seq, ",order=strict"); | |
547 | ||
548 | return 0; | |
549 | } | |
550 | ||
783f6184 RK |
551 | static struct super_operations nilfs_sops = { |
552 | .alloc_inode = nilfs_alloc_inode, | |
553 | .destroy_inode = nilfs_destroy_inode, | |
554 | .dirty_inode = nilfs_dirty_inode, | |
555 | /* .write_inode = nilfs_write_inode, */ | |
556 | /* .put_inode = nilfs_put_inode, */ | |
557 | /* .drop_inode = nilfs_drop_inode, */ | |
558 | .delete_inode = nilfs_delete_inode, | |
559 | .put_super = nilfs_put_super, | |
560 | .write_super = nilfs_write_super, | |
561 | .sync_fs = nilfs_sync_fs, | |
562 | /* .write_super_lockfs */ | |
563 | /* .unlockfs */ | |
564 | .statfs = nilfs_statfs, | |
565 | .remount_fs = nilfs_remount, | |
566 | .clear_inode = nilfs_clear_inode, | |
567 | /* .umount_begin */ | |
b58a285b | 568 | .show_options = nilfs_show_options |
783f6184 RK |
569 | }; |
570 | ||
571 | static struct inode * | |
572 | nilfs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation) | |
573 | { | |
574 | struct inode *inode; | |
575 | ||
576 | if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO && | |
577 | ino != NILFS_SKETCH_INO) | |
578 | return ERR_PTR(-ESTALE); | |
579 | ||
580 | inode = nilfs_iget(sb, ino); | |
581 | if (IS_ERR(inode)) | |
582 | return ERR_CAST(inode); | |
583 | if (generation && inode->i_generation != generation) { | |
584 | iput(inode); | |
585 | return ERR_PTR(-ESTALE); | |
586 | } | |
587 | ||
588 | return inode; | |
589 | } | |
590 | ||
591 | static struct dentry * | |
592 | nilfs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, | |
593 | int fh_type) | |
594 | { | |
595 | return generic_fh_to_dentry(sb, fid, fh_len, fh_type, | |
596 | nilfs_nfs_get_inode); | |
597 | } | |
598 | ||
599 | static struct dentry * | |
600 | nilfs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len, | |
601 | int fh_type) | |
602 | { | |
603 | return generic_fh_to_parent(sb, fid, fh_len, fh_type, | |
604 | nilfs_nfs_get_inode); | |
605 | } | |
606 | ||
607 | static struct export_operations nilfs_export_ops = { | |
608 | .fh_to_dentry = nilfs_fh_to_dentry, | |
609 | .fh_to_parent = nilfs_fh_to_parent, | |
610 | .get_parent = nilfs_get_parent, | |
611 | }; | |
612 | ||
613 | enum { | |
614 | Opt_err_cont, Opt_err_panic, Opt_err_ro, | |
615 | Opt_barrier, Opt_snapshot, Opt_order, | |
616 | Opt_err, | |
617 | }; | |
618 | ||
619 | static match_table_t tokens = { | |
620 | {Opt_err_cont, "errors=continue"}, | |
621 | {Opt_err_panic, "errors=panic"}, | |
622 | {Opt_err_ro, "errors=remount-ro"}, | |
623 | {Opt_barrier, "barrier=%s"}, | |
624 | {Opt_snapshot, "cp=%u"}, | |
625 | {Opt_order, "order=%s"}, | |
626 | {Opt_err, NULL} | |
627 | }; | |
628 | ||
629 | static int match_bool(substring_t *s, int *result) | |
630 | { | |
631 | int len = s->to - s->from; | |
632 | ||
633 | if (strncmp(s->from, "on", len) == 0) | |
634 | *result = 1; | |
635 | else if (strncmp(s->from, "off", len) == 0) | |
636 | *result = 0; | |
637 | else | |
638 | return 1; | |
639 | return 0; | |
640 | } | |
641 | ||
642 | static int parse_options(char *options, struct super_block *sb) | |
643 | { | |
644 | struct nilfs_sb_info *sbi = NILFS_SB(sb); | |
645 | char *p; | |
646 | substring_t args[MAX_OPT_ARGS]; | |
647 | int option; | |
648 | ||
649 | if (!options) | |
650 | return 1; | |
651 | ||
652 | while ((p = strsep(&options, ",")) != NULL) { | |
653 | int token; | |
654 | if (!*p) | |
655 | continue; | |
656 | ||
657 | token = match_token(p, tokens, args); | |
658 | switch (token) { | |
659 | case Opt_barrier: | |
660 | if (match_bool(&args[0], &option)) | |
661 | return 0; | |
662 | if (option) | |
663 | nilfs_set_opt(sbi, BARRIER); | |
664 | else | |
665 | nilfs_clear_opt(sbi, BARRIER); | |
666 | break; | |
667 | case Opt_order: | |
668 | if (strcmp(args[0].from, "relaxed") == 0) | |
669 | /* Ordered data semantics */ | |
670 | nilfs_clear_opt(sbi, STRICT_ORDER); | |
671 | else if (strcmp(args[0].from, "strict") == 0) | |
672 | /* Strict in-order semantics */ | |
673 | nilfs_set_opt(sbi, STRICT_ORDER); | |
674 | else | |
675 | return 0; | |
676 | break; | |
677 | case Opt_err_panic: | |
678 | nilfs_write_opt(sbi, ERROR_MODE, ERRORS_PANIC); | |
679 | break; | |
680 | case Opt_err_ro: | |
681 | nilfs_write_opt(sbi, ERROR_MODE, ERRORS_RO); | |
682 | break; | |
683 | case Opt_err_cont: | |
684 | nilfs_write_opt(sbi, ERROR_MODE, ERRORS_CONT); | |
685 | break; | |
686 | case Opt_snapshot: | |
687 | if (match_int(&args[0], &option) || option <= 0) | |
688 | return 0; | |
689 | if (!(sb->s_flags & MS_RDONLY)) | |
690 | return 0; | |
691 | sbi->s_snapshot_cno = option; | |
692 | nilfs_set_opt(sbi, SNAPSHOT); | |
693 | break; | |
694 | default: | |
695 | printk(KERN_ERR | |
696 | "NILFS: Unrecognized mount option \"%s\"\n", p); | |
697 | return 0; | |
698 | } | |
699 | } | |
700 | return 1; | |
701 | } | |
702 | ||
703 | static inline void | |
704 | nilfs_set_default_options(struct nilfs_sb_info *sbi, | |
705 | struct nilfs_super_block *sbp) | |
706 | { | |
707 | sbi->s_mount_opt = | |
708 | NILFS_MOUNT_ERRORS_CONT | NILFS_MOUNT_BARRIER; | |
709 | } | |
710 | ||
711 | static int nilfs_setup_super(struct nilfs_sb_info *sbi) | |
712 | { | |
713 | struct the_nilfs *nilfs = sbi->s_nilfs; | |
e339ad31 | 714 | struct nilfs_super_block *sbp = nilfs->ns_sbp[0]; |
783f6184 RK |
715 | int max_mnt_count = le16_to_cpu(sbp->s_max_mnt_count); |
716 | int mnt_count = le16_to_cpu(sbp->s_mnt_count); | |
717 | ||
718 | /* nilfs->sem must be locked by the caller. */ | |
719 | if (!(nilfs->ns_mount_state & NILFS_VALID_FS)) { | |
720 | printk(KERN_WARNING "NILFS warning: mounting unchecked fs\n"); | |
721 | } else if (nilfs->ns_mount_state & NILFS_ERROR_FS) { | |
722 | printk(KERN_WARNING | |
723 | "NILFS warning: mounting fs with errors\n"); | |
724 | #if 0 | |
725 | } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) { | |
726 | printk(KERN_WARNING | |
727 | "NILFS warning: maximal mount count reached\n"); | |
728 | #endif | |
729 | } | |
730 | if (!max_mnt_count) | |
731 | sbp->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT); | |
732 | ||
733 | sbp->s_mnt_count = cpu_to_le16(mnt_count + 1); | |
734 | sbp->s_state = cpu_to_le16(le16_to_cpu(sbp->s_state) & ~NILFS_VALID_FS); | |
735 | sbp->s_mtime = cpu_to_le64(get_seconds()); | |
e339ad31 | 736 | return nilfs_commit_super(sbi, 1); |
783f6184 RK |
737 | } |
738 | ||
e339ad31 RK |
739 | struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb, |
740 | u64 pos, int blocksize, | |
741 | struct buffer_head **pbh) | |
783f6184 | 742 | { |
e339ad31 RK |
743 | unsigned long long sb_index = pos; |
744 | unsigned long offset; | |
783f6184 | 745 | |
e339ad31 | 746 | offset = do_div(sb_index, blocksize); |
783f6184 | 747 | *pbh = sb_bread(sb, sb_index); |
e339ad31 | 748 | if (!*pbh) |
783f6184 | 749 | return NULL; |
783f6184 RK |
750 | return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset); |
751 | } | |
752 | ||
783f6184 RK |
753 | int nilfs_store_magic_and_option(struct super_block *sb, |
754 | struct nilfs_super_block *sbp, | |
755 | char *data) | |
756 | { | |
757 | struct nilfs_sb_info *sbi = NILFS_SB(sb); | |
758 | ||
783f6184 RK |
759 | sb->s_magic = le16_to_cpu(sbp->s_magic); |
760 | ||
761 | /* FS independent flags */ | |
762 | #ifdef NILFS_ATIME_DISABLE | |
763 | sb->s_flags |= MS_NOATIME; | |
764 | #endif | |
765 | ||
783f6184 RK |
766 | nilfs_set_default_options(sbi, sbp); |
767 | ||
768 | sbi->s_resuid = le16_to_cpu(sbp->s_def_resuid); | |
769 | sbi->s_resgid = le16_to_cpu(sbp->s_def_resgid); | |
770 | sbi->s_interval = le32_to_cpu(sbp->s_c_interval); | |
771 | sbi->s_watermark = le32_to_cpu(sbp->s_c_block_max); | |
772 | ||
e339ad31 | 773 | return !parse_options(data, sb) ? -EINVAL : 0 ; |
783f6184 RK |
774 | } |
775 | ||
776 | /** | |
777 | * nilfs_fill_super() - initialize a super block instance | |
778 | * @sb: super_block | |
779 | * @data: mount options | |
780 | * @silent: silent mode flag | |
781 | * @nilfs: the_nilfs struct | |
782 | * | |
aa7dfb89 | 783 | * This function is called exclusively by nilfs->ns_mount_mutex. |
783f6184 RK |
784 | * So, the recovery process is protected from other simultaneous mounts. |
785 | */ | |
786 | static int | |
787 | nilfs_fill_super(struct super_block *sb, void *data, int silent, | |
788 | struct the_nilfs *nilfs) | |
789 | { | |
790 | struct nilfs_sb_info *sbi; | |
791 | struct inode *root; | |
792 | __u64 cno; | |
793 | int err; | |
794 | ||
795 | sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); | |
796 | if (!sbi) | |
797 | return -ENOMEM; | |
798 | ||
799 | sb->s_fs_info = sbi; | |
800 | ||
801 | get_nilfs(nilfs); | |
802 | sbi->s_nilfs = nilfs; | |
803 | sbi->s_super = sb; | |
6dd47406 | 804 | atomic_set(&sbi->s_count, 1); |
783f6184 RK |
805 | |
806 | err = init_nilfs(nilfs, sbi, (char *)data); | |
807 | if (err) | |
808 | goto failed_sbi; | |
809 | ||
810 | spin_lock_init(&sbi->s_inode_lock); | |
811 | INIT_LIST_HEAD(&sbi->s_dirty_files); | |
812 | INIT_LIST_HEAD(&sbi->s_list); | |
813 | ||
814 | /* | |
815 | * Following initialization is overlapped because | |
816 | * nilfs_sb_info structure has been cleared at the beginning. | |
817 | * But we reserve them to keep our interest and make ready | |
818 | * for the future change. | |
819 | */ | |
820 | get_random_bytes(&sbi->s_next_generation, | |
821 | sizeof(sbi->s_next_generation)); | |
822 | spin_lock_init(&sbi->s_next_gen_lock); | |
823 | ||
824 | sb->s_op = &nilfs_sops; | |
825 | sb->s_export_op = &nilfs_export_ops; | |
826 | sb->s_root = NULL; | |
61239230 | 827 | sb->s_time_gran = 1; |
783f6184 RK |
828 | |
829 | if (!nilfs_loaded(nilfs)) { | |
830 | err = load_nilfs(nilfs, sbi); | |
831 | if (err) | |
832 | goto failed_sbi; | |
833 | } | |
834 | cno = nilfs_last_cno(nilfs); | |
835 | ||
836 | if (sb->s_flags & MS_RDONLY) { | |
837 | if (nilfs_test_opt(sbi, SNAPSHOT)) { | |
1f5abe7e RK |
838 | err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, |
839 | sbi->s_snapshot_cno); | |
840 | if (err < 0) | |
841 | goto failed_sbi; | |
842 | if (!err) { | |
783f6184 RK |
843 | printk(KERN_ERR |
844 | "NILFS: The specified checkpoint is " | |
845 | "not a snapshot " | |
846 | "(checkpoint number=%llu).\n", | |
847 | (unsigned long long)sbi->s_snapshot_cno); | |
848 | err = -EINVAL; | |
849 | goto failed_sbi; | |
850 | } | |
851 | cno = sbi->s_snapshot_cno; | |
852 | } else | |
853 | /* Read-only mount */ | |
854 | sbi->s_snapshot_cno = cno; | |
855 | } | |
856 | ||
857 | err = nilfs_attach_checkpoint(sbi, cno); | |
858 | if (err) { | |
859 | printk(KERN_ERR "NILFS: error loading a checkpoint" | |
860 | " (checkpoint number=%llu).\n", (unsigned long long)cno); | |
861 | goto failed_sbi; | |
862 | } | |
863 | ||
864 | if (!(sb->s_flags & MS_RDONLY)) { | |
cece5520 | 865 | err = nilfs_attach_segment_constructor(sbi); |
783f6184 RK |
866 | if (err) |
867 | goto failed_checkpoint; | |
868 | } | |
869 | ||
870 | root = nilfs_iget(sb, NILFS_ROOT_INO); | |
871 | if (IS_ERR(root)) { | |
872 | printk(KERN_ERR "NILFS: get root inode failed\n"); | |
873 | err = PTR_ERR(root); | |
874 | goto failed_segctor; | |
875 | } | |
876 | if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) { | |
877 | iput(root); | |
878 | printk(KERN_ERR "NILFS: corrupt root inode.\n"); | |
879 | err = -EINVAL; | |
880 | goto failed_segctor; | |
881 | } | |
882 | sb->s_root = d_alloc_root(root); | |
883 | if (!sb->s_root) { | |
884 | iput(root); | |
885 | printk(KERN_ERR "NILFS: get root dentry failed\n"); | |
886 | err = -ENOMEM; | |
887 | goto failed_segctor; | |
888 | } | |
889 | ||
890 | if (!(sb->s_flags & MS_RDONLY)) { | |
891 | down_write(&nilfs->ns_sem); | |
892 | nilfs_setup_super(sbi); | |
893 | up_write(&nilfs->ns_sem); | |
894 | } | |
895 | ||
896 | err = nilfs_mark_recovery_complete(sbi); | |
897 | if (unlikely(err)) { | |
898 | printk(KERN_ERR "NILFS: recovery failed.\n"); | |
899 | goto failed_root; | |
900 | } | |
901 | ||
e59399d0 | 902 | down_write(&nilfs->ns_super_sem); |
3f82ff55 RK |
903 | if (!nilfs_test_opt(sbi, SNAPSHOT)) |
904 | nilfs->ns_current = sbi; | |
e59399d0 | 905 | up_write(&nilfs->ns_super_sem); |
3f82ff55 | 906 | |
783f6184 RK |
907 | return 0; |
908 | ||
909 | failed_root: | |
910 | dput(sb->s_root); | |
911 | sb->s_root = NULL; | |
912 | ||
913 | failed_segctor: | |
914 | nilfs_detach_segment_constructor(sbi); | |
915 | ||
916 | failed_checkpoint: | |
917 | nilfs_detach_checkpoint(sbi); | |
918 | ||
919 | failed_sbi: | |
920 | put_nilfs(nilfs); | |
921 | sb->s_fs_info = NULL; | |
6dd47406 | 922 | nilfs_put_sbinfo(sbi); |
783f6184 RK |
923 | return err; |
924 | } | |
925 | ||
926 | static int nilfs_remount(struct super_block *sb, int *flags, char *data) | |
927 | { | |
928 | struct nilfs_sb_info *sbi = NILFS_SB(sb); | |
929 | struct nilfs_super_block *sbp; | |
930 | struct the_nilfs *nilfs = sbi->s_nilfs; | |
931 | unsigned long old_sb_flags; | |
932 | struct nilfs_mount_options old_opts; | |
933 | int err; | |
934 | ||
337eb00a AIB |
935 | lock_kernel(); |
936 | ||
e59399d0 | 937 | down_write(&nilfs->ns_super_sem); |
783f6184 RK |
938 | old_sb_flags = sb->s_flags; |
939 | old_opts.mount_opt = sbi->s_mount_opt; | |
940 | old_opts.snapshot_cno = sbi->s_snapshot_cno; | |
941 | ||
942 | if (!parse_options(data, sb)) { | |
943 | err = -EINVAL; | |
944 | goto restore_opts; | |
945 | } | |
946 | sb->s_flags = (sb->s_flags & ~MS_POSIXACL); | |
947 | ||
948 | if ((*flags & MS_RDONLY) && | |
949 | sbi->s_snapshot_cno != old_opts.snapshot_cno) { | |
950 | printk(KERN_WARNING "NILFS (device %s): couldn't " | |
951 | "remount to a different snapshot. \n", | |
952 | sb->s_id); | |
953 | err = -EINVAL; | |
954 | goto restore_opts; | |
955 | } | |
956 | ||
957 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) | |
958 | goto out; | |
959 | if (*flags & MS_RDONLY) { | |
960 | /* Shutting down the segment constructor */ | |
961 | nilfs_detach_segment_constructor(sbi); | |
962 | sb->s_flags |= MS_RDONLY; | |
963 | ||
964 | sbi->s_snapshot_cno = nilfs_last_cno(nilfs); | |
965 | /* nilfs_set_opt(sbi, SNAPSHOT); */ | |
966 | ||
967 | /* | |
968 | * Remounting a valid RW partition RDONLY, so set | |
969 | * the RDONLY flag and then mark the partition as valid again. | |
970 | */ | |
971 | down_write(&nilfs->ns_sem); | |
e339ad31 | 972 | sbp = nilfs->ns_sbp[0]; |
783f6184 RK |
973 | if (!(sbp->s_state & le16_to_cpu(NILFS_VALID_FS)) && |
974 | (nilfs->ns_mount_state & NILFS_VALID_FS)) | |
975 | sbp->s_state = cpu_to_le16(nilfs->ns_mount_state); | |
976 | sbp->s_mtime = cpu_to_le64(get_seconds()); | |
e339ad31 | 977 | nilfs_commit_super(sbi, 1); |
783f6184 RK |
978 | up_write(&nilfs->ns_sem); |
979 | } else { | |
980 | /* | |
981 | * Mounting a RDONLY partition read-write, so reread and | |
982 | * store the current valid flag. (It may have been changed | |
983 | * by fsck since we originally mounted the partition.) | |
984 | */ | |
3f82ff55 | 985 | if (nilfs->ns_current && nilfs->ns_current != sbi) { |
783f6184 | 986 | printk(KERN_WARNING "NILFS (device %s): couldn't " |
3f82ff55 | 987 | "remount because an RW-mount exists.\n", |
783f6184 RK |
988 | sb->s_id); |
989 | err = -EBUSY; | |
e59399d0 | 990 | goto restore_opts; |
783f6184 RK |
991 | } |
992 | if (sbi->s_snapshot_cno != nilfs_last_cno(nilfs)) { | |
993 | printk(KERN_WARNING "NILFS (device %s): couldn't " | |
994 | "remount because the current RO-mount is not " | |
995 | "the latest one.\n", | |
996 | sb->s_id); | |
997 | err = -EINVAL; | |
e59399d0 | 998 | goto restore_opts; |
783f6184 RK |
999 | } |
1000 | sb->s_flags &= ~MS_RDONLY; | |
1001 | nilfs_clear_opt(sbi, SNAPSHOT); | |
1002 | sbi->s_snapshot_cno = 0; | |
1003 | ||
cece5520 | 1004 | err = nilfs_attach_segment_constructor(sbi); |
783f6184 | 1005 | if (err) |
e59399d0 | 1006 | goto restore_opts; |
783f6184 RK |
1007 | |
1008 | down_write(&nilfs->ns_sem); | |
1009 | nilfs_setup_super(sbi); | |
1010 | up_write(&nilfs->ns_sem); | |
1011 | ||
e59399d0 | 1012 | nilfs->ns_current = sbi; |
783f6184 RK |
1013 | } |
1014 | out: | |
e59399d0 | 1015 | up_write(&nilfs->ns_super_sem); |
337eb00a | 1016 | unlock_kernel(); |
783f6184 RK |
1017 | return 0; |
1018 | ||
783f6184 RK |
1019 | restore_opts: |
1020 | sb->s_flags = old_sb_flags; | |
1021 | sbi->s_mount_opt = old_opts.mount_opt; | |
1022 | sbi->s_snapshot_cno = old_opts.snapshot_cno; | |
e59399d0 | 1023 | up_write(&nilfs->ns_super_sem); |
337eb00a | 1024 | unlock_kernel(); |
783f6184 RK |
1025 | return err; |
1026 | } | |
1027 | ||
1028 | struct nilfs_super_data { | |
1029 | struct block_device *bdev; | |
6dd47406 | 1030 | struct nilfs_sb_info *sbi; |
783f6184 RK |
1031 | __u64 cno; |
1032 | int flags; | |
1033 | }; | |
1034 | ||
1035 | /** | |
1036 | * nilfs_identify - pre-read mount options needed to identify mount instance | |
1037 | * @data: mount options | |
1038 | * @sd: nilfs_super_data | |
1039 | */ | |
1040 | static int nilfs_identify(char *data, struct nilfs_super_data *sd) | |
1041 | { | |
1042 | char *p, *options = data; | |
1043 | substring_t args[MAX_OPT_ARGS]; | |
1044 | int option, token; | |
1045 | int ret = 0; | |
1046 | ||
1047 | do { | |
1048 | p = strsep(&options, ","); | |
1049 | if (p != NULL && *p) { | |
1050 | token = match_token(p, tokens, args); | |
1051 | if (token == Opt_snapshot) { | |
1052 | if (!(sd->flags & MS_RDONLY)) | |
1053 | ret++; | |
1054 | else { | |
1055 | ret = match_int(&args[0], &option); | |
1056 | if (!ret) { | |
1057 | if (option > 0) | |
1058 | sd->cno = option; | |
1059 | else | |
1060 | ret++; | |
1061 | } | |
1062 | } | |
1063 | } | |
1064 | if (ret) | |
1065 | printk(KERN_ERR | |
1066 | "NILFS: invalid mount option: %s\n", p); | |
1067 | } | |
1068 | if (!options) | |
1069 | break; | |
1070 | BUG_ON(options == data); | |
1071 | *(options - 1) = ','; | |
1072 | } while (!ret); | |
1073 | return ret; | |
1074 | } | |
1075 | ||
1076 | static int nilfs_set_bdev_super(struct super_block *s, void *data) | |
1077 | { | |
1078 | struct nilfs_super_data *sd = data; | |
1079 | ||
1080 | s->s_bdev = sd->bdev; | |
1081 | s->s_dev = s->s_bdev->bd_dev; | |
1082 | return 0; | |
1083 | } | |
1084 | ||
1085 | static int nilfs_test_bdev_super(struct super_block *s, void *data) | |
783f6184 RK |
1086 | { |
1087 | struct nilfs_super_data *sd = data; | |
6dd47406 RK |
1088 | |
1089 | return sd->sbi && s->s_fs_info == (void *)sd->sbi; | |
783f6184 RK |
1090 | } |
1091 | ||
1092 | static int | |
1093 | nilfs_get_sb(struct file_system_type *fs_type, int flags, | |
1094 | const char *dev_name, void *data, struct vfsmount *mnt) | |
1095 | { | |
1096 | struct nilfs_super_data sd; | |
33c8e57c RK |
1097 | struct super_block *s; |
1098 | struct the_nilfs *nilfs; | |
783f6184 RK |
1099 | int err, need_to_close = 1; |
1100 | ||
1101 | sd.bdev = open_bdev_exclusive(dev_name, flags, fs_type); | |
1102 | if (IS_ERR(sd.bdev)) | |
1103 | return PTR_ERR(sd.bdev); | |
1104 | ||
1105 | /* | |
1106 | * To get mount instance using sget() vfs-routine, NILFS needs | |
1107 | * much more information than normal filesystems to identify mount | |
1108 | * instance. For snapshot mounts, not only a mount type (ro-mount | |
1109 | * or rw-mount) but also a checkpoint number is required. | |
783f6184 RK |
1110 | */ |
1111 | sd.cno = 0; | |
1112 | sd.flags = flags; | |
1113 | if (nilfs_identify((char *)data, &sd)) { | |
1114 | err = -EINVAL; | |
1115 | goto failed; | |
1116 | } | |
1117 | ||
33c8e57c RK |
1118 | nilfs = find_or_create_nilfs(sd.bdev); |
1119 | if (!nilfs) { | |
1120 | err = -ENOMEM; | |
1121 | goto failed; | |
1122 | } | |
1123 | ||
aa7dfb89 | 1124 | mutex_lock(&nilfs->ns_mount_mutex); |
3f82ff55 RK |
1125 | |
1126 | if (!sd.cno) { | |
1127 | /* | |
1128 | * Check if an exclusive mount exists or not. | |
1129 | * Snapshot mounts coexist with a current mount | |
1130 | * (i.e. rw-mount or ro-mount), whereas rw-mount and | |
1131 | * ro-mount are mutually exclusive. | |
1132 | */ | |
e59399d0 | 1133 | down_read(&nilfs->ns_super_sem); |
3f82ff55 RK |
1134 | if (nilfs->ns_current && |
1135 | ((nilfs->ns_current->s_super->s_flags ^ flags) | |
1136 | & MS_RDONLY)) { | |
e59399d0 | 1137 | up_read(&nilfs->ns_super_sem); |
3f82ff55 RK |
1138 | err = -EBUSY; |
1139 | goto failed_unlock; | |
1140 | } | |
e59399d0 | 1141 | up_read(&nilfs->ns_super_sem); |
783f6184 RK |
1142 | } |
1143 | ||
1144 | /* | |
6dd47406 | 1145 | * Find existing nilfs_sb_info struct |
783f6184 | 1146 | */ |
6dd47406 RK |
1147 | sd.sbi = nilfs_find_sbinfo(nilfs, !(flags & MS_RDONLY), sd.cno); |
1148 | ||
33c8e57c RK |
1149 | if (!sd.cno) |
1150 | /* trying to get the latest checkpoint. */ | |
1151 | sd.cno = nilfs_last_cno(nilfs); | |
783f6184 | 1152 | |
6dd47406 RK |
1153 | /* |
1154 | * Get super block instance holding the nilfs_sb_info struct. | |
1155 | * A new instance is allocated if no existing mount is present or | |
1156 | * existing instance has been unmounted. | |
1157 | */ | |
33c8e57c | 1158 | s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, &sd); |
6dd47406 RK |
1159 | if (sd.sbi) |
1160 | nilfs_put_sbinfo(sd.sbi); | |
1161 | ||
33c8e57c RK |
1162 | if (IS_ERR(s)) { |
1163 | err = PTR_ERR(s); | |
1164 | goto failed_unlock; | |
783f6184 RK |
1165 | } |
1166 | ||
1167 | if (!s->s_root) { | |
1168 | char b[BDEVNAME_SIZE]; | |
1169 | ||
33c8e57c | 1170 | /* New superblock instance created */ |
783f6184 RK |
1171 | s->s_flags = flags; |
1172 | strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id)); | |
1173 | sb_set_blocksize(s, block_size(sd.bdev)); | |
1174 | ||
1175 | err = nilfs_fill_super(s, data, flags & MS_VERBOSE, nilfs); | |
1176 | if (err) | |
1177 | goto cancel_new; | |
1178 | ||
1179 | s->s_flags |= MS_ACTIVE; | |
1180 | need_to_close = 0; | |
783f6184 RK |
1181 | } |
1182 | ||
aa7dfb89 | 1183 | mutex_unlock(&nilfs->ns_mount_mutex); |
783f6184 RK |
1184 | put_nilfs(nilfs); |
1185 | if (need_to_close) | |
1186 | close_bdev_exclusive(sd.bdev, flags); | |
1187 | simple_set_mnt(mnt, s); | |
1188 | return 0; | |
1189 | ||
783f6184 | 1190 | failed_unlock: |
aa7dfb89 | 1191 | mutex_unlock(&nilfs->ns_mount_mutex); |
33c8e57c | 1192 | put_nilfs(nilfs); |
783f6184 RK |
1193 | failed: |
1194 | close_bdev_exclusive(sd.bdev, flags); | |
1195 | ||
1196 | return err; | |
1197 | ||
1198 | cancel_new: | |
1199 | /* Abandoning the newly allocated superblock */ | |
aa7dfb89 | 1200 | mutex_unlock(&nilfs->ns_mount_mutex); |
33c8e57c | 1201 | put_nilfs(nilfs); |
783f6184 RK |
1202 | up_write(&s->s_umount); |
1203 | deactivate_super(s); | |
1204 | /* | |
1205 | * deactivate_super() invokes close_bdev_exclusive(). | |
1206 | * We must finish all post-cleaning before this call; | |
aa7dfb89 | 1207 | * put_nilfs() needs the block device. |
783f6184 RK |
1208 | */ |
1209 | return err; | |
1210 | } | |
1211 | ||
783f6184 RK |
1212 | struct file_system_type nilfs_fs_type = { |
1213 | .owner = THIS_MODULE, | |
1214 | .name = "nilfs2", | |
1215 | .get_sb = nilfs_get_sb, | |
1216 | .kill_sb = kill_block_super, | |
1217 | .fs_flags = FS_REQUIRES_DEV, | |
1218 | }; | |
1219 | ||
1220 | static int __init init_nilfs_fs(void) | |
1221 | { | |
1222 | int err; | |
1223 | ||
1224 | err = nilfs_init_inode_cache(); | |
1225 | if (err) | |
1226 | goto failed; | |
1227 | ||
1228 | err = nilfs_init_transaction_cache(); | |
1229 | if (err) | |
1230 | goto failed_inode_cache; | |
1231 | ||
1232 | err = nilfs_init_segbuf_cache(); | |
1233 | if (err) | |
1234 | goto failed_transaction_cache; | |
1235 | ||
1236 | err = nilfs_btree_path_cache_init(); | |
1237 | if (err) | |
1238 | goto failed_segbuf_cache; | |
1239 | ||
1240 | err = register_filesystem(&nilfs_fs_type); | |
1241 | if (err) | |
1242 | goto failed_btree_path_cache; | |
1243 | ||
1244 | return 0; | |
1245 | ||
1246 | failed_btree_path_cache: | |
1247 | nilfs_btree_path_cache_destroy(); | |
1248 | ||
1249 | failed_segbuf_cache: | |
1250 | nilfs_destroy_segbuf_cache(); | |
1251 | ||
1252 | failed_transaction_cache: | |
1253 | nilfs_destroy_transaction_cache(); | |
1254 | ||
1255 | failed_inode_cache: | |
1256 | nilfs_destroy_inode_cache(); | |
1257 | ||
1258 | failed: | |
1259 | return err; | |
1260 | } | |
1261 | ||
1262 | static void __exit exit_nilfs_fs(void) | |
1263 | { | |
1264 | nilfs_destroy_segbuf_cache(); | |
1265 | nilfs_destroy_transaction_cache(); | |
1266 | nilfs_destroy_inode_cache(); | |
1267 | nilfs_btree_path_cache_destroy(); | |
1268 | unregister_filesystem(&nilfs_fs_type); | |
1269 | } | |
1270 | ||
1271 | module_init(init_nilfs_fs) | |
1272 | module_exit(exit_nilfs_fs) |