]>
Commit | Line | Data |
---|---|---|
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 | * Written by Ryusuke Konishi. | |
17 | */ | |
18 | /* | |
19 | * linux/fs/ext2/super.c | |
20 | * | |
21 | * Copyright (C) 1992, 1993, 1994, 1995 | |
22 | * Remy Card (card@masi.ibp.fr) | |
23 | * Laboratoire MASI - Institut Blaise Pascal | |
24 | * Universite Pierre et Marie Curie (Paris VI) | |
25 | * | |
26 | * from | |
27 | * | |
28 | * linux/fs/minix/inode.c | |
29 | * | |
30 | * Copyright (C) 1991, 1992 Linus Torvalds | |
31 | * | |
32 | * Big-endian to little-endian byte-swapping/bitmaps by | |
33 | * David S. Miller (davem@caip.rutgers.edu), 1995 | |
34 | */ | |
35 | ||
36 | #include <linux/module.h> | |
37 | #include <linux/string.h> | |
38 | #include <linux/slab.h> | |
39 | #include <linux/init.h> | |
40 | #include <linux/blkdev.h> | |
41 | #include <linux/parser.h> | |
42 | #include <linux/crc32.h> | |
43 | #include <linux/vfs.h> | |
44 | #include <linux/writeback.h> | |
45 | #include <linux/seq_file.h> | |
46 | #include <linux/mount.h> | |
47 | #include "nilfs.h" | |
48 | #include "export.h" | |
49 | #include "mdt.h" | |
50 | #include "alloc.h" | |
51 | #include "btree.h" | |
52 | #include "btnode.h" | |
53 | #include "page.h" | |
54 | #include "cpfile.h" | |
55 | #include "sufile.h" /* nilfs_sufile_resize(), nilfs_sufile_set_alloc_range() */ | |
56 | #include "ifile.h" | |
57 | #include "dat.h" | |
58 | #include "segment.h" | |
59 | #include "segbuf.h" | |
60 | ||
61 | MODULE_AUTHOR("NTT Corp."); | |
62 | MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem " | |
63 | "(NILFS)"); | |
64 | MODULE_LICENSE("GPL"); | |
65 | ||
66 | static struct kmem_cache *nilfs_inode_cachep; | |
67 | struct kmem_cache *nilfs_transaction_cachep; | |
68 | struct kmem_cache *nilfs_segbuf_cachep; | |
69 | struct kmem_cache *nilfs_btree_path_cache; | |
70 | ||
71 | static int nilfs_setup_super(struct super_block *sb, int is_mount); | |
72 | static int nilfs_remount(struct super_block *sb, int *flags, char *data); | |
73 | ||
74 | void __nilfs_msg(struct super_block *sb, const char *level, const char *fmt, | |
75 | ...) | |
76 | { | |
77 | struct va_format vaf; | |
78 | va_list args; | |
79 | ||
80 | va_start(args, fmt); | |
81 | vaf.fmt = fmt; | |
82 | vaf.va = &args; | |
83 | if (sb) | |
84 | printk("%sNILFS (%s): %pV\n", level, sb->s_id, &vaf); | |
85 | else | |
86 | printk("%sNILFS: %pV\n", level, &vaf); | |
87 | va_end(args); | |
88 | } | |
89 | ||
90 | static void nilfs_set_error(struct super_block *sb) | |
91 | { | |
92 | struct the_nilfs *nilfs = sb->s_fs_info; | |
93 | struct nilfs_super_block **sbp; | |
94 | ||
95 | down_write(&nilfs->ns_sem); | |
96 | if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) { | |
97 | nilfs->ns_mount_state |= NILFS_ERROR_FS; | |
98 | sbp = nilfs_prepare_super(sb, 0); | |
99 | if (likely(sbp)) { | |
100 | sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS); | |
101 | if (sbp[1]) | |
102 | sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS); | |
103 | nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); | |
104 | } | |
105 | } | |
106 | up_write(&nilfs->ns_sem); | |
107 | } | |
108 | ||
109 | /** | |
110 | * __nilfs_error() - report failure condition on a filesystem | |
111 | * | |
112 | * __nilfs_error() sets an ERROR_FS flag on the superblock as well as | |
113 | * reporting an error message. This function should be called when | |
114 | * NILFS detects incoherences or defects of meta data on disk. | |
115 | * | |
116 | * This implements the body of nilfs_error() macro. Normally, | |
117 | * nilfs_error() should be used. As for sustainable errors such as a | |
118 | * single-shot I/O error, nilfs_msg() should be used instead. | |
119 | * | |
120 | * Callers should not add a trailing newline since this will do it. | |
121 | */ | |
122 | void __nilfs_error(struct super_block *sb, const char *function, | |
123 | const char *fmt, ...) | |
124 | { | |
125 | struct the_nilfs *nilfs = sb->s_fs_info; | |
126 | struct va_format vaf; | |
127 | va_list args; | |
128 | ||
129 | va_start(args, fmt); | |
130 | ||
131 | vaf.fmt = fmt; | |
132 | vaf.va = &args; | |
133 | ||
134 | printk(KERN_CRIT "NILFS error (device %s): %s: %pV\n", | |
135 | sb->s_id, function, &vaf); | |
136 | ||
137 | va_end(args); | |
138 | ||
139 | if (!(sb->s_flags & MS_RDONLY)) { | |
140 | nilfs_set_error(sb); | |
141 | ||
142 | if (nilfs_test_opt(nilfs, ERRORS_RO)) { | |
143 | printk(KERN_CRIT "Remounting filesystem read-only\n"); | |
144 | sb->s_flags |= MS_RDONLY; | |
145 | } | |
146 | } | |
147 | ||
148 | if (nilfs_test_opt(nilfs, ERRORS_PANIC)) | |
149 | panic("NILFS (device %s): panic forced after error\n", | |
150 | sb->s_id); | |
151 | } | |
152 | ||
153 | struct inode *nilfs_alloc_inode(struct super_block *sb) | |
154 | { | |
155 | struct nilfs_inode_info *ii; | |
156 | ||
157 | ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS); | |
158 | if (!ii) | |
159 | return NULL; | |
160 | ii->i_bh = NULL; | |
161 | ii->i_state = 0; | |
162 | ii->i_cno = 0; | |
163 | ii->vfs_inode.i_version = 1; | |
164 | nilfs_mapping_init(&ii->i_btnode_cache, &ii->vfs_inode); | |
165 | return &ii->vfs_inode; | |
166 | } | |
167 | ||
168 | static void nilfs_i_callback(struct rcu_head *head) | |
169 | { | |
170 | struct inode *inode = container_of(head, struct inode, i_rcu); | |
171 | ||
172 | if (nilfs_is_metadata_file_inode(inode)) | |
173 | nilfs_mdt_destroy(inode); | |
174 | ||
175 | kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode)); | |
176 | } | |
177 | ||
178 | void nilfs_destroy_inode(struct inode *inode) | |
179 | { | |
180 | call_rcu(&inode->i_rcu, nilfs_i_callback); | |
181 | } | |
182 | ||
183 | static int nilfs_sync_super(struct super_block *sb, int flag) | |
184 | { | |
185 | struct the_nilfs *nilfs = sb->s_fs_info; | |
186 | int err; | |
187 | ||
188 | retry: | |
189 | set_buffer_dirty(nilfs->ns_sbh[0]); | |
190 | if (nilfs_test_opt(nilfs, BARRIER)) { | |
191 | err = __sync_dirty_buffer(nilfs->ns_sbh[0], | |
192 | REQ_SYNC | REQ_PREFLUSH | REQ_FUA); | |
193 | } else { | |
194 | err = sync_dirty_buffer(nilfs->ns_sbh[0]); | |
195 | } | |
196 | ||
197 | if (unlikely(err)) { | |
198 | nilfs_msg(sb, KERN_ERR, "unable to write superblock: err=%d", | |
199 | err); | |
200 | if (err == -EIO && nilfs->ns_sbh[1]) { | |
201 | /* | |
202 | * sbp[0] points to newer log than sbp[1], | |
203 | * so copy sbp[0] to sbp[1] to take over sbp[0]. | |
204 | */ | |
205 | memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0], | |
206 | nilfs->ns_sbsize); | |
207 | nilfs_fall_back_super_block(nilfs); | |
208 | goto retry; | |
209 | } | |
210 | } else { | |
211 | struct nilfs_super_block *sbp = nilfs->ns_sbp[0]; | |
212 | ||
213 | nilfs->ns_sbwcount++; | |
214 | ||
215 | /* | |
216 | * The latest segment becomes trailable from the position | |
217 | * written in superblock. | |
218 | */ | |
219 | clear_nilfs_discontinued(nilfs); | |
220 | ||
221 | /* update GC protection for recent segments */ | |
222 | if (nilfs->ns_sbh[1]) { | |
223 | if (flag == NILFS_SB_COMMIT_ALL) { | |
224 | set_buffer_dirty(nilfs->ns_sbh[1]); | |
225 | if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0) | |
226 | goto out; | |
227 | } | |
228 | if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) < | |
229 | le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno)) | |
230 | sbp = nilfs->ns_sbp[1]; | |
231 | } | |
232 | ||
233 | spin_lock(&nilfs->ns_last_segment_lock); | |
234 | nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq); | |
235 | spin_unlock(&nilfs->ns_last_segment_lock); | |
236 | } | |
237 | out: | |
238 | return err; | |
239 | } | |
240 | ||
241 | void nilfs_set_log_cursor(struct nilfs_super_block *sbp, | |
242 | struct the_nilfs *nilfs) | |
243 | { | |
244 | sector_t nfreeblocks; | |
245 | ||
246 | /* nilfs->ns_sem must be locked by the caller. */ | |
247 | nilfs_count_free_blocks(nilfs, &nfreeblocks); | |
248 | sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks); | |
249 | ||
250 | spin_lock(&nilfs->ns_last_segment_lock); | |
251 | sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq); | |
252 | sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg); | |
253 | sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno); | |
254 | spin_unlock(&nilfs->ns_last_segment_lock); | |
255 | } | |
256 | ||
257 | struct nilfs_super_block **nilfs_prepare_super(struct super_block *sb, | |
258 | int flip) | |
259 | { | |
260 | struct the_nilfs *nilfs = sb->s_fs_info; | |
261 | struct nilfs_super_block **sbp = nilfs->ns_sbp; | |
262 | ||
263 | /* nilfs->ns_sem must be locked by the caller. */ | |
264 | if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { | |
265 | if (sbp[1] && | |
266 | sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) { | |
267 | memcpy(sbp[0], sbp[1], nilfs->ns_sbsize); | |
268 | } else { | |
269 | nilfs_msg(sb, KERN_CRIT, "superblock broke"); | |
270 | return NULL; | |
271 | } | |
272 | } else if (sbp[1] && | |
273 | sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { | |
274 | memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); | |
275 | } | |
276 | ||
277 | if (flip && sbp[1]) | |
278 | nilfs_swap_super_block(nilfs); | |
279 | ||
280 | return sbp; | |
281 | } | |
282 | ||
283 | int nilfs_commit_super(struct super_block *sb, int flag) | |
284 | { | |
285 | struct the_nilfs *nilfs = sb->s_fs_info; | |
286 | struct nilfs_super_block **sbp = nilfs->ns_sbp; | |
287 | time_t t; | |
288 | ||
289 | /* nilfs->ns_sem must be locked by the caller. */ | |
290 | t = get_seconds(); | |
291 | nilfs->ns_sbwtime = t; | |
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 (flag == NILFS_SB_COMMIT_ALL && sbp[1]) { | |
298 | sbp[1]->s_wtime = sbp[0]->s_wtime; | |
299 | sbp[1]->s_sum = 0; | |
300 | sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, | |
301 | (unsigned char *)sbp[1], | |
302 | nilfs->ns_sbsize)); | |
303 | } | |
304 | clear_nilfs_sb_dirty(nilfs); | |
305 | nilfs->ns_flushed_device = 1; | |
306 | /* make sure store to ns_flushed_device cannot be reordered */ | |
307 | smp_wmb(); | |
308 | return nilfs_sync_super(sb, flag); | |
309 | } | |
310 | ||
311 | /** | |
312 | * nilfs_cleanup_super() - write filesystem state for cleanup | |
313 | * @sb: super block instance to be unmounted or degraded to read-only | |
314 | * | |
315 | * This function restores state flags in the on-disk super block. | |
316 | * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the | |
317 | * filesystem was not clean previously. | |
318 | */ | |
319 | int nilfs_cleanup_super(struct super_block *sb) | |
320 | { | |
321 | struct the_nilfs *nilfs = sb->s_fs_info; | |
322 | struct nilfs_super_block **sbp; | |
323 | int flag = NILFS_SB_COMMIT; | |
324 | int ret = -EIO; | |
325 | ||
326 | sbp = nilfs_prepare_super(sb, 0); | |
327 | if (sbp) { | |
328 | sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state); | |
329 | nilfs_set_log_cursor(sbp[0], nilfs); | |
330 | if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) { | |
331 | /* | |
332 | * make the "clean" flag also to the opposite | |
333 | * super block if both super blocks point to | |
334 | * the same checkpoint. | |
335 | */ | |
336 | sbp[1]->s_state = sbp[0]->s_state; | |
337 | flag = NILFS_SB_COMMIT_ALL; | |
338 | } | |
339 | ret = nilfs_commit_super(sb, flag); | |
340 | } | |
341 | return ret; | |
342 | } | |
343 | ||
344 | /** | |
345 | * nilfs_move_2nd_super - relocate secondary super block | |
346 | * @sb: super block instance | |
347 | * @sb2off: new offset of the secondary super block (in bytes) | |
348 | */ | |
349 | static int nilfs_move_2nd_super(struct super_block *sb, loff_t sb2off) | |
350 | { | |
351 | struct the_nilfs *nilfs = sb->s_fs_info; | |
352 | struct buffer_head *nsbh; | |
353 | struct nilfs_super_block *nsbp; | |
354 | sector_t blocknr, newblocknr; | |
355 | unsigned long offset; | |
356 | int sb2i; /* array index of the secondary superblock */ | |
357 | int ret = 0; | |
358 | ||
359 | /* nilfs->ns_sem must be locked by the caller. */ | |
360 | if (nilfs->ns_sbh[1] && | |
361 | nilfs->ns_sbh[1]->b_blocknr > nilfs->ns_first_data_block) { | |
362 | sb2i = 1; | |
363 | blocknr = nilfs->ns_sbh[1]->b_blocknr; | |
364 | } else if (nilfs->ns_sbh[0]->b_blocknr > nilfs->ns_first_data_block) { | |
365 | sb2i = 0; | |
366 | blocknr = nilfs->ns_sbh[0]->b_blocknr; | |
367 | } else { | |
368 | sb2i = -1; | |
369 | blocknr = 0; | |
370 | } | |
371 | if (sb2i >= 0 && (u64)blocknr << nilfs->ns_blocksize_bits == sb2off) | |
372 | goto out; /* super block location is unchanged */ | |
373 | ||
374 | /* Get new super block buffer */ | |
375 | newblocknr = sb2off >> nilfs->ns_blocksize_bits; | |
376 | offset = sb2off & (nilfs->ns_blocksize - 1); | |
377 | nsbh = sb_getblk(sb, newblocknr); | |
378 | if (!nsbh) { | |
379 | nilfs_msg(sb, KERN_WARNING, | |
380 | "unable to move secondary superblock to block %llu", | |
381 | (unsigned long long)newblocknr); | |
382 | ret = -EIO; | |
383 | goto out; | |
384 | } | |
385 | nsbp = (void *)nsbh->b_data + offset; | |
386 | memset(nsbp, 0, nilfs->ns_blocksize); | |
387 | ||
388 | if (sb2i >= 0) { | |
389 | memcpy(nsbp, nilfs->ns_sbp[sb2i], nilfs->ns_sbsize); | |
390 | brelse(nilfs->ns_sbh[sb2i]); | |
391 | nilfs->ns_sbh[sb2i] = nsbh; | |
392 | nilfs->ns_sbp[sb2i] = nsbp; | |
393 | } else if (nilfs->ns_sbh[0]->b_blocknr < nilfs->ns_first_data_block) { | |
394 | /* secondary super block will be restored to index 1 */ | |
395 | nilfs->ns_sbh[1] = nsbh; | |
396 | nilfs->ns_sbp[1] = nsbp; | |
397 | } else { | |
398 | brelse(nsbh); | |
399 | } | |
400 | out: | |
401 | return ret; | |
402 | } | |
403 | ||
404 | /** | |
405 | * nilfs_resize_fs - resize the filesystem | |
406 | * @sb: super block instance | |
407 | * @newsize: new size of the filesystem (in bytes) | |
408 | */ | |
409 | int nilfs_resize_fs(struct super_block *sb, __u64 newsize) | |
410 | { | |
411 | struct the_nilfs *nilfs = sb->s_fs_info; | |
412 | struct nilfs_super_block **sbp; | |
413 | __u64 devsize, newnsegs; | |
414 | loff_t sb2off; | |
415 | int ret; | |
416 | ||
417 | ret = -ERANGE; | |
418 | devsize = i_size_read(sb->s_bdev->bd_inode); | |
419 | if (newsize > devsize) | |
420 | goto out; | |
421 | ||
422 | /* | |
423 | * Write lock is required to protect some functions depending | |
424 | * on the number of segments, the number of reserved segments, | |
425 | * and so forth. | |
426 | */ | |
427 | down_write(&nilfs->ns_segctor_sem); | |
428 | ||
429 | sb2off = NILFS_SB2_OFFSET_BYTES(newsize); | |
430 | newnsegs = sb2off >> nilfs->ns_blocksize_bits; | |
431 | do_div(newnsegs, nilfs->ns_blocks_per_segment); | |
432 | ||
433 | ret = nilfs_sufile_resize(nilfs->ns_sufile, newnsegs); | |
434 | up_write(&nilfs->ns_segctor_sem); | |
435 | if (ret < 0) | |
436 | goto out; | |
437 | ||
438 | ret = nilfs_construct_segment(sb); | |
439 | if (ret < 0) | |
440 | goto out; | |
441 | ||
442 | down_write(&nilfs->ns_sem); | |
443 | nilfs_move_2nd_super(sb, sb2off); | |
444 | ret = -EIO; | |
445 | sbp = nilfs_prepare_super(sb, 0); | |
446 | if (likely(sbp)) { | |
447 | nilfs_set_log_cursor(sbp[0], nilfs); | |
448 | /* | |
449 | * Drop NILFS_RESIZE_FS flag for compatibility with | |
450 | * mount-time resize which may be implemented in a | |
451 | * future release. | |
452 | */ | |
453 | sbp[0]->s_state = cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & | |
454 | ~NILFS_RESIZE_FS); | |
455 | sbp[0]->s_dev_size = cpu_to_le64(newsize); | |
456 | sbp[0]->s_nsegments = cpu_to_le64(nilfs->ns_nsegments); | |
457 | if (sbp[1]) | |
458 | memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); | |
459 | ret = nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); | |
460 | } | |
461 | up_write(&nilfs->ns_sem); | |
462 | ||
463 | /* | |
464 | * Reset the range of allocatable segments last. This order | |
465 | * is important in the case of expansion because the secondary | |
466 | * superblock must be protected from log write until migration | |
467 | * completes. | |
468 | */ | |
469 | if (!ret) | |
470 | nilfs_sufile_set_alloc_range(nilfs->ns_sufile, 0, newnsegs - 1); | |
471 | out: | |
472 | return ret; | |
473 | } | |
474 | ||
475 | static void nilfs_put_super(struct super_block *sb) | |
476 | { | |
477 | struct the_nilfs *nilfs = sb->s_fs_info; | |
478 | ||
479 | nilfs_detach_log_writer(sb); | |
480 | ||
481 | if (!(sb->s_flags & MS_RDONLY)) { | |
482 | down_write(&nilfs->ns_sem); | |
483 | nilfs_cleanup_super(sb); | |
484 | up_write(&nilfs->ns_sem); | |
485 | } | |
486 | ||
487 | iput(nilfs->ns_sufile); | |
488 | iput(nilfs->ns_cpfile); | |
489 | iput(nilfs->ns_dat); | |
490 | ||
491 | destroy_nilfs(nilfs); | |
492 | sb->s_fs_info = NULL; | |
493 | } | |
494 | ||
495 | static int nilfs_sync_fs(struct super_block *sb, int wait) | |
496 | { | |
497 | struct the_nilfs *nilfs = sb->s_fs_info; | |
498 | struct nilfs_super_block **sbp; | |
499 | int err = 0; | |
500 | ||
501 | /* This function is called when super block should be written back */ | |
502 | if (wait) | |
503 | err = nilfs_construct_segment(sb); | |
504 | ||
505 | down_write(&nilfs->ns_sem); | |
506 | if (nilfs_sb_dirty(nilfs)) { | |
507 | sbp = nilfs_prepare_super(sb, nilfs_sb_will_flip(nilfs)); | |
508 | if (likely(sbp)) { | |
509 | nilfs_set_log_cursor(sbp[0], nilfs); | |
510 | nilfs_commit_super(sb, NILFS_SB_COMMIT); | |
511 | } | |
512 | } | |
513 | up_write(&nilfs->ns_sem); | |
514 | ||
515 | if (!err) | |
516 | err = nilfs_flush_device(nilfs); | |
517 | ||
518 | return err; | |
519 | } | |
520 | ||
521 | int nilfs_attach_checkpoint(struct super_block *sb, __u64 cno, int curr_mnt, | |
522 | struct nilfs_root **rootp) | |
523 | { | |
524 | struct the_nilfs *nilfs = sb->s_fs_info; | |
525 | struct nilfs_root *root; | |
526 | struct nilfs_checkpoint *raw_cp; | |
527 | struct buffer_head *bh_cp; | |
528 | int err = -ENOMEM; | |
529 | ||
530 | root = nilfs_find_or_create_root( | |
531 | nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno); | |
532 | if (!root) | |
533 | return err; | |
534 | ||
535 | if (root->ifile) | |
536 | goto reuse; /* already attached checkpoint */ | |
537 | ||
538 | down_read(&nilfs->ns_segctor_sem); | |
539 | err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp, | |
540 | &bh_cp); | |
541 | up_read(&nilfs->ns_segctor_sem); | |
542 | if (unlikely(err)) { | |
543 | if (err == -ENOENT || err == -EINVAL) { | |
544 | nilfs_msg(sb, KERN_ERR, | |
545 | "Invalid checkpoint (checkpoint number=%llu)", | |
546 | (unsigned long long)cno); | |
547 | err = -EINVAL; | |
548 | } | |
549 | goto failed; | |
550 | } | |
551 | ||
552 | err = nilfs_ifile_read(sb, root, nilfs->ns_inode_size, | |
553 | &raw_cp->cp_ifile_inode, &root->ifile); | |
554 | if (err) | |
555 | goto failed_bh; | |
556 | ||
557 | atomic64_set(&root->inodes_count, | |
558 | le64_to_cpu(raw_cp->cp_inodes_count)); | |
559 | atomic64_set(&root->blocks_count, | |
560 | le64_to_cpu(raw_cp->cp_blocks_count)); | |
561 | ||
562 | nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); | |
563 | ||
564 | reuse: | |
565 | *rootp = root; | |
566 | return 0; | |
567 | ||
568 | failed_bh: | |
569 | nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp); | |
570 | failed: | |
571 | nilfs_put_root(root); | |
572 | ||
573 | return err; | |
574 | } | |
575 | ||
576 | static int nilfs_freeze(struct super_block *sb) | |
577 | { | |
578 | struct the_nilfs *nilfs = sb->s_fs_info; | |
579 | int err; | |
580 | ||
581 | if (sb->s_flags & MS_RDONLY) | |
582 | return 0; | |
583 | ||
584 | /* Mark super block clean */ | |
585 | down_write(&nilfs->ns_sem); | |
586 | err = nilfs_cleanup_super(sb); | |
587 | up_write(&nilfs->ns_sem); | |
588 | return err; | |
589 | } | |
590 | ||
591 | static int nilfs_unfreeze(struct super_block *sb) | |
592 | { | |
593 | struct the_nilfs *nilfs = sb->s_fs_info; | |
594 | ||
595 | if (sb->s_flags & MS_RDONLY) | |
596 | return 0; | |
597 | ||
598 | down_write(&nilfs->ns_sem); | |
599 | nilfs_setup_super(sb, false); | |
600 | up_write(&nilfs->ns_sem); | |
601 | return 0; | |
602 | } | |
603 | ||
604 | static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf) | |
605 | { | |
606 | struct super_block *sb = dentry->d_sb; | |
607 | struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root; | |
608 | struct the_nilfs *nilfs = root->nilfs; | |
609 | u64 id = huge_encode_dev(sb->s_bdev->bd_dev); | |
610 | unsigned long long blocks; | |
611 | unsigned long overhead; | |
612 | unsigned long nrsvblocks; | |
613 | sector_t nfreeblocks; | |
614 | u64 nmaxinodes, nfreeinodes; | |
615 | int err; | |
616 | ||
617 | /* | |
618 | * Compute all of the segment blocks | |
619 | * | |
620 | * The blocks before first segment and after last segment | |
621 | * are excluded. | |
622 | */ | |
623 | blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments | |
624 | - nilfs->ns_first_data_block; | |
625 | nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment; | |
626 | ||
627 | /* | |
628 | * Compute the overhead | |
629 | * | |
630 | * When distributing meta data blocks outside segment structure, | |
631 | * We must count them as the overhead. | |
632 | */ | |
633 | overhead = 0; | |
634 | ||
635 | err = nilfs_count_free_blocks(nilfs, &nfreeblocks); | |
636 | if (unlikely(err)) | |
637 | return err; | |
638 | ||
639 | err = nilfs_ifile_count_free_inodes(root->ifile, | |
640 | &nmaxinodes, &nfreeinodes); | |
641 | if (unlikely(err)) { | |
642 | nilfs_msg(sb, KERN_WARNING, | |
643 | "failed to count free inodes: err=%d", err); | |
644 | if (err == -ERANGE) { | |
645 | /* | |
646 | * If nilfs_palloc_count_max_entries() returns | |
647 | * -ERANGE error code then we simply treat | |
648 | * curent inodes count as maximum possible and | |
649 | * zero as free inodes value. | |
650 | */ | |
651 | nmaxinodes = atomic64_read(&root->inodes_count); | |
652 | nfreeinodes = 0; | |
653 | err = 0; | |
654 | } else | |
655 | return err; | |
656 | } | |
657 | ||
658 | buf->f_type = NILFS_SUPER_MAGIC; | |
659 | buf->f_bsize = sb->s_blocksize; | |
660 | buf->f_blocks = blocks - overhead; | |
661 | buf->f_bfree = nfreeblocks; | |
662 | buf->f_bavail = (buf->f_bfree >= nrsvblocks) ? | |
663 | (buf->f_bfree - nrsvblocks) : 0; | |
664 | buf->f_files = nmaxinodes; | |
665 | buf->f_ffree = nfreeinodes; | |
666 | buf->f_namelen = NILFS_NAME_LEN; | |
667 | buf->f_fsid.val[0] = (u32)id; | |
668 | buf->f_fsid.val[1] = (u32)(id >> 32); | |
669 | ||
670 | return 0; | |
671 | } | |
672 | ||
673 | static int nilfs_show_options(struct seq_file *seq, struct dentry *dentry) | |
674 | { | |
675 | struct super_block *sb = dentry->d_sb; | |
676 | struct the_nilfs *nilfs = sb->s_fs_info; | |
677 | struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root; | |
678 | ||
679 | if (!nilfs_test_opt(nilfs, BARRIER)) | |
680 | seq_puts(seq, ",nobarrier"); | |
681 | if (root->cno != NILFS_CPTREE_CURRENT_CNO) | |
682 | seq_printf(seq, ",cp=%llu", (unsigned long long)root->cno); | |
683 | if (nilfs_test_opt(nilfs, ERRORS_PANIC)) | |
684 | seq_puts(seq, ",errors=panic"); | |
685 | if (nilfs_test_opt(nilfs, ERRORS_CONT)) | |
686 | seq_puts(seq, ",errors=continue"); | |
687 | if (nilfs_test_opt(nilfs, STRICT_ORDER)) | |
688 | seq_puts(seq, ",order=strict"); | |
689 | if (nilfs_test_opt(nilfs, NORECOVERY)) | |
690 | seq_puts(seq, ",norecovery"); | |
691 | if (nilfs_test_opt(nilfs, DISCARD)) | |
692 | seq_puts(seq, ",discard"); | |
693 | ||
694 | return 0; | |
695 | } | |
696 | ||
697 | static const struct super_operations nilfs_sops = { | |
698 | .alloc_inode = nilfs_alloc_inode, | |
699 | .destroy_inode = nilfs_destroy_inode, | |
700 | .dirty_inode = nilfs_dirty_inode, | |
701 | .evict_inode = nilfs_evict_inode, | |
702 | .put_super = nilfs_put_super, | |
703 | .sync_fs = nilfs_sync_fs, | |
704 | .freeze_fs = nilfs_freeze, | |
705 | .unfreeze_fs = nilfs_unfreeze, | |
706 | .statfs = nilfs_statfs, | |
707 | .remount_fs = nilfs_remount, | |
708 | .show_options = nilfs_show_options | |
709 | }; | |
710 | ||
711 | enum { | |
712 | Opt_err_cont, Opt_err_panic, Opt_err_ro, | |
713 | Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery, | |
714 | Opt_discard, Opt_nodiscard, Opt_err, | |
715 | }; | |
716 | ||
717 | static match_table_t tokens = { | |
718 | {Opt_err_cont, "errors=continue"}, | |
719 | {Opt_err_panic, "errors=panic"}, | |
720 | {Opt_err_ro, "errors=remount-ro"}, | |
721 | {Opt_barrier, "barrier"}, | |
722 | {Opt_nobarrier, "nobarrier"}, | |
723 | {Opt_snapshot, "cp=%u"}, | |
724 | {Opt_order, "order=%s"}, | |
725 | {Opt_norecovery, "norecovery"}, | |
726 | {Opt_discard, "discard"}, | |
727 | {Opt_nodiscard, "nodiscard"}, | |
728 | {Opt_err, NULL} | |
729 | }; | |
730 | ||
731 | static int parse_options(char *options, struct super_block *sb, int is_remount) | |
732 | { | |
733 | struct the_nilfs *nilfs = sb->s_fs_info; | |
734 | char *p; | |
735 | substring_t args[MAX_OPT_ARGS]; | |
736 | ||
737 | if (!options) | |
738 | return 1; | |
739 | ||
740 | while ((p = strsep(&options, ",")) != NULL) { | |
741 | int token; | |
742 | ||
743 | if (!*p) | |
744 | continue; | |
745 | ||
746 | token = match_token(p, tokens, args); | |
747 | switch (token) { | |
748 | case Opt_barrier: | |
749 | nilfs_set_opt(nilfs, BARRIER); | |
750 | break; | |
751 | case Opt_nobarrier: | |
752 | nilfs_clear_opt(nilfs, BARRIER); | |
753 | break; | |
754 | case Opt_order: | |
755 | if (strcmp(args[0].from, "relaxed") == 0) | |
756 | /* Ordered data semantics */ | |
757 | nilfs_clear_opt(nilfs, STRICT_ORDER); | |
758 | else if (strcmp(args[0].from, "strict") == 0) | |
759 | /* Strict in-order semantics */ | |
760 | nilfs_set_opt(nilfs, STRICT_ORDER); | |
761 | else | |
762 | return 0; | |
763 | break; | |
764 | case Opt_err_panic: | |
765 | nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_PANIC); | |
766 | break; | |
767 | case Opt_err_ro: | |
768 | nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_RO); | |
769 | break; | |
770 | case Opt_err_cont: | |
771 | nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_CONT); | |
772 | break; | |
773 | case Opt_snapshot: | |
774 | if (is_remount) { | |
775 | nilfs_msg(sb, KERN_ERR, | |
776 | "\"%s\" option is invalid for remount", | |
777 | p); | |
778 | return 0; | |
779 | } | |
780 | break; | |
781 | case Opt_norecovery: | |
782 | nilfs_set_opt(nilfs, NORECOVERY); | |
783 | break; | |
784 | case Opt_discard: | |
785 | nilfs_set_opt(nilfs, DISCARD); | |
786 | break; | |
787 | case Opt_nodiscard: | |
788 | nilfs_clear_opt(nilfs, DISCARD); | |
789 | break; | |
790 | default: | |
791 | nilfs_msg(sb, KERN_ERR, | |
792 | "unrecognized mount option \"%s\"", p); | |
793 | return 0; | |
794 | } | |
795 | } | |
796 | return 1; | |
797 | } | |
798 | ||
799 | static inline void | |
800 | nilfs_set_default_options(struct super_block *sb, | |
801 | struct nilfs_super_block *sbp) | |
802 | { | |
803 | struct the_nilfs *nilfs = sb->s_fs_info; | |
804 | ||
805 | nilfs->ns_mount_opt = | |
806 | NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER; | |
807 | } | |
808 | ||
809 | static int nilfs_setup_super(struct super_block *sb, int is_mount) | |
810 | { | |
811 | struct the_nilfs *nilfs = sb->s_fs_info; | |
812 | struct nilfs_super_block **sbp; | |
813 | int max_mnt_count; | |
814 | int mnt_count; | |
815 | ||
816 | /* nilfs->ns_sem must be locked by the caller. */ | |
817 | sbp = nilfs_prepare_super(sb, 0); | |
818 | if (!sbp) | |
819 | return -EIO; | |
820 | ||
821 | if (!is_mount) | |
822 | goto skip_mount_setup; | |
823 | ||
824 | max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count); | |
825 | mnt_count = le16_to_cpu(sbp[0]->s_mnt_count); | |
826 | ||
827 | if (nilfs->ns_mount_state & NILFS_ERROR_FS) { | |
828 | nilfs_msg(sb, KERN_WARNING, "mounting fs with errors"); | |
829 | #if 0 | |
830 | } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) { | |
831 | nilfs_msg(sb, KERN_WARNING, "maximal mount count reached"); | |
832 | #endif | |
833 | } | |
834 | if (!max_mnt_count) | |
835 | sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT); | |
836 | ||
837 | sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1); | |
838 | sbp[0]->s_mtime = cpu_to_le64(get_seconds()); | |
839 | ||
840 | skip_mount_setup: | |
841 | sbp[0]->s_state = | |
842 | cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS); | |
843 | /* synchronize sbp[1] with sbp[0] */ | |
844 | if (sbp[1]) | |
845 | memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); | |
846 | return nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL); | |
847 | } | |
848 | ||
849 | struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb, | |
850 | u64 pos, int blocksize, | |
851 | struct buffer_head **pbh) | |
852 | { | |
853 | unsigned long long sb_index = pos; | |
854 | unsigned long offset; | |
855 | ||
856 | offset = do_div(sb_index, blocksize); | |
857 | *pbh = sb_bread(sb, sb_index); | |
858 | if (!*pbh) | |
859 | return NULL; | |
860 | return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset); | |
861 | } | |
862 | ||
863 | int nilfs_store_magic_and_option(struct super_block *sb, | |
864 | struct nilfs_super_block *sbp, | |
865 | char *data) | |
866 | { | |
867 | struct the_nilfs *nilfs = sb->s_fs_info; | |
868 | ||
869 | sb->s_magic = le16_to_cpu(sbp->s_magic); | |
870 | ||
871 | /* FS independent flags */ | |
872 | #ifdef NILFS_ATIME_DISABLE | |
873 | sb->s_flags |= MS_NOATIME; | |
874 | #endif | |
875 | ||
876 | nilfs_set_default_options(sb, sbp); | |
877 | ||
878 | nilfs->ns_resuid = le16_to_cpu(sbp->s_def_resuid); | |
879 | nilfs->ns_resgid = le16_to_cpu(sbp->s_def_resgid); | |
880 | nilfs->ns_interval = le32_to_cpu(sbp->s_c_interval); | |
881 | nilfs->ns_watermark = le32_to_cpu(sbp->s_c_block_max); | |
882 | ||
883 | return !parse_options(data, sb, 0) ? -EINVAL : 0; | |
884 | } | |
885 | ||
886 | int nilfs_check_feature_compatibility(struct super_block *sb, | |
887 | struct nilfs_super_block *sbp) | |
888 | { | |
889 | __u64 features; | |
890 | ||
891 | features = le64_to_cpu(sbp->s_feature_incompat) & | |
892 | ~NILFS_FEATURE_INCOMPAT_SUPP; | |
893 | if (features) { | |
894 | nilfs_msg(sb, KERN_ERR, | |
895 | "couldn't mount because of unsupported optional features (%llx)", | |
896 | (unsigned long long)features); | |
897 | return -EINVAL; | |
898 | } | |
899 | features = le64_to_cpu(sbp->s_feature_compat_ro) & | |
900 | ~NILFS_FEATURE_COMPAT_RO_SUPP; | |
901 | if (!(sb->s_flags & MS_RDONLY) && features) { | |
902 | nilfs_msg(sb, KERN_ERR, | |
903 | "couldn't mount RDWR because of unsupported optional features (%llx)", | |
904 | (unsigned long long)features); | |
905 | return -EINVAL; | |
906 | } | |
907 | return 0; | |
908 | } | |
909 | ||
910 | static int nilfs_get_root_dentry(struct super_block *sb, | |
911 | struct nilfs_root *root, | |
912 | struct dentry **root_dentry) | |
913 | { | |
914 | struct inode *inode; | |
915 | struct dentry *dentry; | |
916 | int ret = 0; | |
917 | ||
918 | inode = nilfs_iget(sb, root, NILFS_ROOT_INO); | |
919 | if (IS_ERR(inode)) { | |
920 | ret = PTR_ERR(inode); | |
921 | nilfs_msg(sb, KERN_ERR, "error %d getting root inode", ret); | |
922 | goto out; | |
923 | } | |
924 | if (!S_ISDIR(inode->i_mode) || !inode->i_blocks || !inode->i_size) { | |
925 | iput(inode); | |
926 | nilfs_msg(sb, KERN_ERR, "corrupt root inode"); | |
927 | ret = -EINVAL; | |
928 | goto out; | |
929 | } | |
930 | ||
931 | if (root->cno == NILFS_CPTREE_CURRENT_CNO) { | |
932 | dentry = d_find_alias(inode); | |
933 | if (!dentry) { | |
934 | dentry = d_make_root(inode); | |
935 | if (!dentry) { | |
936 | ret = -ENOMEM; | |
937 | goto failed_dentry; | |
938 | } | |
939 | } else { | |
940 | iput(inode); | |
941 | } | |
942 | } else { | |
943 | dentry = d_obtain_root(inode); | |
944 | if (IS_ERR(dentry)) { | |
945 | ret = PTR_ERR(dentry); | |
946 | goto failed_dentry; | |
947 | } | |
948 | } | |
949 | *root_dentry = dentry; | |
950 | out: | |
951 | return ret; | |
952 | ||
953 | failed_dentry: | |
954 | nilfs_msg(sb, KERN_ERR, "error %d getting root dentry", ret); | |
955 | goto out; | |
956 | } | |
957 | ||
958 | static int nilfs_attach_snapshot(struct super_block *s, __u64 cno, | |
959 | struct dentry **root_dentry) | |
960 | { | |
961 | struct the_nilfs *nilfs = s->s_fs_info; | |
962 | struct nilfs_root *root; | |
963 | int ret; | |
964 | ||
965 | mutex_lock(&nilfs->ns_snapshot_mount_mutex); | |
966 | ||
967 | down_read(&nilfs->ns_segctor_sem); | |
968 | ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno); | |
969 | up_read(&nilfs->ns_segctor_sem); | |
970 | if (ret < 0) { | |
971 | ret = (ret == -ENOENT) ? -EINVAL : ret; | |
972 | goto out; | |
973 | } else if (!ret) { | |
974 | nilfs_msg(s, KERN_ERR, | |
975 | "The specified checkpoint is not a snapshot (checkpoint number=%llu)", | |
976 | (unsigned long long)cno); | |
977 | ret = -EINVAL; | |
978 | goto out; | |
979 | } | |
980 | ||
981 | ret = nilfs_attach_checkpoint(s, cno, false, &root); | |
982 | if (ret) { | |
983 | nilfs_msg(s, KERN_ERR, | |
984 | "error %d while loading snapshot (checkpoint number=%llu)", | |
985 | ret, (unsigned long long)cno); | |
986 | goto out; | |
987 | } | |
988 | ret = nilfs_get_root_dentry(s, root, root_dentry); | |
989 | nilfs_put_root(root); | |
990 | out: | |
991 | mutex_unlock(&nilfs->ns_snapshot_mount_mutex); | |
992 | return ret; | |
993 | } | |
994 | ||
995 | /** | |
996 | * nilfs_tree_is_busy() - try to shrink dentries of a checkpoint | |
997 | * @root_dentry: root dentry of the tree to be shrunk | |
998 | * | |
999 | * This function returns true if the tree was in-use. | |
1000 | */ | |
1001 | static bool nilfs_tree_is_busy(struct dentry *root_dentry) | |
1002 | { | |
1003 | shrink_dcache_parent(root_dentry); | |
1004 | return d_count(root_dentry) > 1; | |
1005 | } | |
1006 | ||
1007 | int nilfs_checkpoint_is_mounted(struct super_block *sb, __u64 cno) | |
1008 | { | |
1009 | struct the_nilfs *nilfs = sb->s_fs_info; | |
1010 | struct nilfs_root *root; | |
1011 | struct inode *inode; | |
1012 | struct dentry *dentry; | |
1013 | int ret; | |
1014 | ||
1015 | if (cno > nilfs->ns_cno) | |
1016 | return false; | |
1017 | ||
1018 | if (cno >= nilfs_last_cno(nilfs)) | |
1019 | return true; /* protect recent checkpoints */ | |
1020 | ||
1021 | ret = false; | |
1022 | root = nilfs_lookup_root(nilfs, cno); | |
1023 | if (root) { | |
1024 | inode = nilfs_ilookup(sb, root, NILFS_ROOT_INO); | |
1025 | if (inode) { | |
1026 | dentry = d_find_alias(inode); | |
1027 | if (dentry) { | |
1028 | ret = nilfs_tree_is_busy(dentry); | |
1029 | dput(dentry); | |
1030 | } | |
1031 | iput(inode); | |
1032 | } | |
1033 | nilfs_put_root(root); | |
1034 | } | |
1035 | return ret; | |
1036 | } | |
1037 | ||
1038 | /** | |
1039 | * nilfs_fill_super() - initialize a super block instance | |
1040 | * @sb: super_block | |
1041 | * @data: mount options | |
1042 | * @silent: silent mode flag | |
1043 | * | |
1044 | * This function is called exclusively by nilfs->ns_mount_mutex. | |
1045 | * So, the recovery process is protected from other simultaneous mounts. | |
1046 | */ | |
1047 | static int | |
1048 | nilfs_fill_super(struct super_block *sb, void *data, int silent) | |
1049 | { | |
1050 | struct the_nilfs *nilfs; | |
1051 | struct nilfs_root *fsroot; | |
1052 | __u64 cno; | |
1053 | int err; | |
1054 | ||
1055 | nilfs = alloc_nilfs(sb); | |
1056 | if (!nilfs) | |
1057 | return -ENOMEM; | |
1058 | ||
1059 | sb->s_fs_info = nilfs; | |
1060 | ||
1061 | err = init_nilfs(nilfs, sb, (char *)data); | |
1062 | if (err) | |
1063 | goto failed_nilfs; | |
1064 | ||
1065 | sb->s_op = &nilfs_sops; | |
1066 | sb->s_export_op = &nilfs_export_ops; | |
1067 | sb->s_root = NULL; | |
1068 | sb->s_time_gran = 1; | |
1069 | sb->s_max_links = NILFS_LINK_MAX; | |
1070 | ||
1071 | sb->s_bdi = &bdev_get_queue(sb->s_bdev)->backing_dev_info; | |
1072 | ||
1073 | err = load_nilfs(nilfs, sb); | |
1074 | if (err) | |
1075 | goto failed_nilfs; | |
1076 | ||
1077 | cno = nilfs_last_cno(nilfs); | |
1078 | err = nilfs_attach_checkpoint(sb, cno, true, &fsroot); | |
1079 | if (err) { | |
1080 | nilfs_msg(sb, KERN_ERR, | |
1081 | "error %d while loading last checkpoint (checkpoint number=%llu)", | |
1082 | err, (unsigned long long)cno); | |
1083 | goto failed_unload; | |
1084 | } | |
1085 | ||
1086 | if (!(sb->s_flags & MS_RDONLY)) { | |
1087 | err = nilfs_attach_log_writer(sb, fsroot); | |
1088 | if (err) | |
1089 | goto failed_checkpoint; | |
1090 | } | |
1091 | ||
1092 | err = nilfs_get_root_dentry(sb, fsroot, &sb->s_root); | |
1093 | if (err) | |
1094 | goto failed_segctor; | |
1095 | ||
1096 | nilfs_put_root(fsroot); | |
1097 | ||
1098 | if (!(sb->s_flags & MS_RDONLY)) { | |
1099 | down_write(&nilfs->ns_sem); | |
1100 | nilfs_setup_super(sb, true); | |
1101 | up_write(&nilfs->ns_sem); | |
1102 | } | |
1103 | ||
1104 | return 0; | |
1105 | ||
1106 | failed_segctor: | |
1107 | nilfs_detach_log_writer(sb); | |
1108 | ||
1109 | failed_checkpoint: | |
1110 | nilfs_put_root(fsroot); | |
1111 | ||
1112 | failed_unload: | |
1113 | iput(nilfs->ns_sufile); | |
1114 | iput(nilfs->ns_cpfile); | |
1115 | iput(nilfs->ns_dat); | |
1116 | ||
1117 | failed_nilfs: | |
1118 | destroy_nilfs(nilfs); | |
1119 | return err; | |
1120 | } | |
1121 | ||
1122 | static int nilfs_remount(struct super_block *sb, int *flags, char *data) | |
1123 | { | |
1124 | struct the_nilfs *nilfs = sb->s_fs_info; | |
1125 | unsigned long old_sb_flags; | |
1126 | unsigned long old_mount_opt; | |
1127 | int err; | |
1128 | ||
1129 | sync_filesystem(sb); | |
1130 | old_sb_flags = sb->s_flags; | |
1131 | old_mount_opt = nilfs->ns_mount_opt; | |
1132 | ||
1133 | if (!parse_options(data, sb, 1)) { | |
1134 | err = -EINVAL; | |
1135 | goto restore_opts; | |
1136 | } | |
1137 | sb->s_flags = (sb->s_flags & ~MS_POSIXACL); | |
1138 | ||
1139 | err = -EINVAL; | |
1140 | ||
1141 | if (!nilfs_valid_fs(nilfs)) { | |
1142 | nilfs_msg(sb, KERN_WARNING, | |
1143 | "couldn't remount because the filesystem is in an incomplete recovery state"); | |
1144 | goto restore_opts; | |
1145 | } | |
1146 | ||
1147 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) | |
1148 | goto out; | |
1149 | if (*flags & MS_RDONLY) { | |
1150 | /* Shutting down log writer */ | |
1151 | nilfs_detach_log_writer(sb); | |
1152 | sb->s_flags |= MS_RDONLY; | |
1153 | ||
1154 | /* | |
1155 | * Remounting a valid RW partition RDONLY, so set | |
1156 | * the RDONLY flag and then mark the partition as valid again. | |
1157 | */ | |
1158 | down_write(&nilfs->ns_sem); | |
1159 | nilfs_cleanup_super(sb); | |
1160 | up_write(&nilfs->ns_sem); | |
1161 | } else { | |
1162 | __u64 features; | |
1163 | struct nilfs_root *root; | |
1164 | ||
1165 | /* | |
1166 | * Mounting a RDONLY partition read-write, so reread and | |
1167 | * store the current valid flag. (It may have been changed | |
1168 | * by fsck since we originally mounted the partition.) | |
1169 | */ | |
1170 | down_read(&nilfs->ns_sem); | |
1171 | features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) & | |
1172 | ~NILFS_FEATURE_COMPAT_RO_SUPP; | |
1173 | up_read(&nilfs->ns_sem); | |
1174 | if (features) { | |
1175 | nilfs_msg(sb, KERN_WARNING, | |
1176 | "couldn't remount RDWR because of unsupported optional features (%llx)", | |
1177 | (unsigned long long)features); | |
1178 | err = -EROFS; | |
1179 | goto restore_opts; | |
1180 | } | |
1181 | ||
1182 | sb->s_flags &= ~MS_RDONLY; | |
1183 | ||
1184 | root = NILFS_I(d_inode(sb->s_root))->i_root; | |
1185 | err = nilfs_attach_log_writer(sb, root); | |
1186 | if (err) | |
1187 | goto restore_opts; | |
1188 | ||
1189 | down_write(&nilfs->ns_sem); | |
1190 | nilfs_setup_super(sb, true); | |
1191 | up_write(&nilfs->ns_sem); | |
1192 | } | |
1193 | out: | |
1194 | return 0; | |
1195 | ||
1196 | restore_opts: | |
1197 | sb->s_flags = old_sb_flags; | |
1198 | nilfs->ns_mount_opt = old_mount_opt; | |
1199 | return err; | |
1200 | } | |
1201 | ||
1202 | struct nilfs_super_data { | |
1203 | struct block_device *bdev; | |
1204 | __u64 cno; | |
1205 | int flags; | |
1206 | }; | |
1207 | ||
1208 | static int nilfs_parse_snapshot_option(const char *option, | |
1209 | const substring_t *arg, | |
1210 | struct nilfs_super_data *sd) | |
1211 | { | |
1212 | unsigned long long val; | |
1213 | const char *msg = NULL; | |
1214 | int err; | |
1215 | ||
1216 | if (!(sd->flags & MS_RDONLY)) { | |
1217 | msg = "read-only option is not specified"; | |
1218 | goto parse_error; | |
1219 | } | |
1220 | ||
1221 | err = kstrtoull(arg->from, 0, &val); | |
1222 | if (err) { | |
1223 | if (err == -ERANGE) | |
1224 | msg = "too large checkpoint number"; | |
1225 | else | |
1226 | msg = "malformed argument"; | |
1227 | goto parse_error; | |
1228 | } else if (val == 0) { | |
1229 | msg = "invalid checkpoint number 0"; | |
1230 | goto parse_error; | |
1231 | } | |
1232 | sd->cno = val; | |
1233 | return 0; | |
1234 | ||
1235 | parse_error: | |
1236 | nilfs_msg(NULL, KERN_ERR, "invalid option \"%s\": %s", option, msg); | |
1237 | return 1; | |
1238 | } | |
1239 | ||
1240 | /** | |
1241 | * nilfs_identify - pre-read mount options needed to identify mount instance | |
1242 | * @data: mount options | |
1243 | * @sd: nilfs_super_data | |
1244 | */ | |
1245 | static int nilfs_identify(char *data, struct nilfs_super_data *sd) | |
1246 | { | |
1247 | char *p, *options = data; | |
1248 | substring_t args[MAX_OPT_ARGS]; | |
1249 | int token; | |
1250 | int ret = 0; | |
1251 | ||
1252 | do { | |
1253 | p = strsep(&options, ","); | |
1254 | if (p != NULL && *p) { | |
1255 | token = match_token(p, tokens, args); | |
1256 | if (token == Opt_snapshot) | |
1257 | ret = nilfs_parse_snapshot_option(p, &args[0], | |
1258 | sd); | |
1259 | } | |
1260 | if (!options) | |
1261 | break; | |
1262 | BUG_ON(options == data); | |
1263 | *(options - 1) = ','; | |
1264 | } while (!ret); | |
1265 | return ret; | |
1266 | } | |
1267 | ||
1268 | static int nilfs_set_bdev_super(struct super_block *s, void *data) | |
1269 | { | |
1270 | s->s_bdev = data; | |
1271 | s->s_dev = s->s_bdev->bd_dev; | |
1272 | return 0; | |
1273 | } | |
1274 | ||
1275 | static int nilfs_test_bdev_super(struct super_block *s, void *data) | |
1276 | { | |
1277 | return (void *)s->s_bdev == data; | |
1278 | } | |
1279 | ||
1280 | static struct dentry * | |
1281 | nilfs_mount(struct file_system_type *fs_type, int flags, | |
1282 | const char *dev_name, void *data) | |
1283 | { | |
1284 | struct nilfs_super_data sd; | |
1285 | struct super_block *s; | |
1286 | fmode_t mode = FMODE_READ | FMODE_EXCL; | |
1287 | struct dentry *root_dentry; | |
1288 | int err, s_new = false; | |
1289 | ||
1290 | if (!(flags & MS_RDONLY)) | |
1291 | mode |= FMODE_WRITE; | |
1292 | ||
1293 | sd.bdev = blkdev_get_by_path(dev_name, mode, fs_type); | |
1294 | if (IS_ERR(sd.bdev)) | |
1295 | return ERR_CAST(sd.bdev); | |
1296 | ||
1297 | sd.cno = 0; | |
1298 | sd.flags = flags; | |
1299 | if (nilfs_identify((char *)data, &sd)) { | |
1300 | err = -EINVAL; | |
1301 | goto failed; | |
1302 | } | |
1303 | ||
1304 | /* | |
1305 | * once the super is inserted into the list by sget, s_umount | |
1306 | * will protect the lockfs code from trying to start a snapshot | |
1307 | * while we are mounting | |
1308 | */ | |
1309 | mutex_lock(&sd.bdev->bd_fsfreeze_mutex); | |
1310 | if (sd.bdev->bd_fsfreeze_count > 0) { | |
1311 | mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); | |
1312 | err = -EBUSY; | |
1313 | goto failed; | |
1314 | } | |
1315 | s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, flags, | |
1316 | sd.bdev); | |
1317 | mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); | |
1318 | if (IS_ERR(s)) { | |
1319 | err = PTR_ERR(s); | |
1320 | goto failed; | |
1321 | } | |
1322 | ||
1323 | if (!s->s_root) { | |
1324 | s_new = true; | |
1325 | ||
1326 | /* New superblock instance created */ | |
1327 | s->s_mode = mode; | |
1328 | snprintf(s->s_id, sizeof(s->s_id), "%pg", sd.bdev); | |
1329 | sb_set_blocksize(s, block_size(sd.bdev)); | |
1330 | ||
1331 | err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0); | |
1332 | if (err) | |
1333 | goto failed_super; | |
1334 | ||
1335 | s->s_flags |= MS_ACTIVE; | |
1336 | } else if (!sd.cno) { | |
1337 | if (nilfs_tree_is_busy(s->s_root)) { | |
1338 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
1339 | nilfs_msg(s, KERN_ERR, | |
1340 | "the device already has a %s mount.", | |
1341 | (s->s_flags & MS_RDONLY) ? | |
1342 | "read-only" : "read/write"); | |
1343 | err = -EBUSY; | |
1344 | goto failed_super; | |
1345 | } | |
1346 | } else { | |
1347 | /* | |
1348 | * Try remount to setup mount states if the current | |
1349 | * tree is not mounted and only snapshots use this sb. | |
1350 | */ | |
1351 | err = nilfs_remount(s, &flags, data); | |
1352 | if (err) | |
1353 | goto failed_super; | |
1354 | } | |
1355 | } | |
1356 | ||
1357 | if (sd.cno) { | |
1358 | err = nilfs_attach_snapshot(s, sd.cno, &root_dentry); | |
1359 | if (err) | |
1360 | goto failed_super; | |
1361 | } else { | |
1362 | root_dentry = dget(s->s_root); | |
1363 | } | |
1364 | ||
1365 | if (!s_new) | |
1366 | blkdev_put(sd.bdev, mode); | |
1367 | ||
1368 | return root_dentry; | |
1369 | ||
1370 | failed_super: | |
1371 | deactivate_locked_super(s); | |
1372 | ||
1373 | failed: | |
1374 | if (!s_new) | |
1375 | blkdev_put(sd.bdev, mode); | |
1376 | return ERR_PTR(err); | |
1377 | } | |
1378 | ||
1379 | struct file_system_type nilfs_fs_type = { | |
1380 | .owner = THIS_MODULE, | |
1381 | .name = "nilfs2", | |
1382 | .mount = nilfs_mount, | |
1383 | .kill_sb = kill_block_super, | |
1384 | .fs_flags = FS_REQUIRES_DEV, | |
1385 | }; | |
1386 | MODULE_ALIAS_FS("nilfs2"); | |
1387 | ||
1388 | static void nilfs_inode_init_once(void *obj) | |
1389 | { | |
1390 | struct nilfs_inode_info *ii = obj; | |
1391 | ||
1392 | INIT_LIST_HEAD(&ii->i_dirty); | |
1393 | #ifdef CONFIG_NILFS_XATTR | |
1394 | init_rwsem(&ii->xattr_sem); | |
1395 | #endif | |
1396 | address_space_init_once(&ii->i_btnode_cache); | |
1397 | ii->i_bmap = &ii->i_bmap_data; | |
1398 | inode_init_once(&ii->vfs_inode); | |
1399 | } | |
1400 | ||
1401 | static void nilfs_segbuf_init_once(void *obj) | |
1402 | { | |
1403 | memset(obj, 0, sizeof(struct nilfs_segment_buffer)); | |
1404 | } | |
1405 | ||
1406 | static void nilfs_destroy_cachep(void) | |
1407 | { | |
1408 | /* | |
1409 | * Make sure all delayed rcu free inodes are flushed before we | |
1410 | * destroy cache. | |
1411 | */ | |
1412 | rcu_barrier(); | |
1413 | ||
1414 | kmem_cache_destroy(nilfs_inode_cachep); | |
1415 | kmem_cache_destroy(nilfs_transaction_cachep); | |
1416 | kmem_cache_destroy(nilfs_segbuf_cachep); | |
1417 | kmem_cache_destroy(nilfs_btree_path_cache); | |
1418 | } | |
1419 | ||
1420 | static int __init nilfs_init_cachep(void) | |
1421 | { | |
1422 | nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache", | |
1423 | sizeof(struct nilfs_inode_info), 0, | |
1424 | SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT, | |
1425 | nilfs_inode_init_once); | |
1426 | if (!nilfs_inode_cachep) | |
1427 | goto fail; | |
1428 | ||
1429 | nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache", | |
1430 | sizeof(struct nilfs_transaction_info), 0, | |
1431 | SLAB_RECLAIM_ACCOUNT, NULL); | |
1432 | if (!nilfs_transaction_cachep) | |
1433 | goto fail; | |
1434 | ||
1435 | nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache", | |
1436 | sizeof(struct nilfs_segment_buffer), 0, | |
1437 | SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once); | |
1438 | if (!nilfs_segbuf_cachep) | |
1439 | goto fail; | |
1440 | ||
1441 | nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache", | |
1442 | sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX, | |
1443 | 0, 0, NULL); | |
1444 | if (!nilfs_btree_path_cache) | |
1445 | goto fail; | |
1446 | ||
1447 | return 0; | |
1448 | ||
1449 | fail: | |
1450 | nilfs_destroy_cachep(); | |
1451 | return -ENOMEM; | |
1452 | } | |
1453 | ||
1454 | static int __init init_nilfs_fs(void) | |
1455 | { | |
1456 | int err; | |
1457 | ||
1458 | err = nilfs_init_cachep(); | |
1459 | if (err) | |
1460 | goto fail; | |
1461 | ||
1462 | err = nilfs_sysfs_init(); | |
1463 | if (err) | |
1464 | goto free_cachep; | |
1465 | ||
1466 | err = register_filesystem(&nilfs_fs_type); | |
1467 | if (err) | |
1468 | goto deinit_sysfs_entry; | |
1469 | ||
1470 | printk(KERN_INFO "NILFS version 2 loaded\n"); | |
1471 | return 0; | |
1472 | ||
1473 | deinit_sysfs_entry: | |
1474 | nilfs_sysfs_exit(); | |
1475 | free_cachep: | |
1476 | nilfs_destroy_cachep(); | |
1477 | fail: | |
1478 | return err; | |
1479 | } | |
1480 | ||
1481 | static void __exit exit_nilfs_fs(void) | |
1482 | { | |
1483 | nilfs_destroy_cachep(); | |
1484 | nilfs_sysfs_exit(); | |
1485 | unregister_filesystem(&nilfs_fs_type); | |
1486 | } | |
1487 | ||
1488 | module_init(init_nilfs_fs) | |
1489 | module_exit(exit_nilfs_fs) |