1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * NILFS module and super block management. |
4 | * |
5 | * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. |
6 | * |
7 | * Written by Ryusuke Konishi. |
8 | */ |
9 | /* |
10 | * linux/fs/ext2/super.c |
11 | * |
12 | * Copyright (C) 1992, 1993, 1994, 1995 |
13 | * Remy Card (card@masi.ibp.fr) |
14 | * Laboratoire MASI - Institut Blaise Pascal |
15 | * Universite Pierre et Marie Curie (Paris VI) |
16 | * |
17 | * from |
18 | * |
19 | * linux/fs/minix/inode.c |
20 | * |
21 | * Copyright (C) 1991, 1992 Linus Torvalds |
22 | * |
23 | * Big-endian to little-endian byte-swapping/bitmaps by |
24 | * David S. Miller (davem@caip.rutgers.edu), 1995 |
25 | */ |
26 | |
27 | #include <linux/module.h> |
28 | #include <linux/string.h> |
29 | #include <linux/slab.h> |
30 | #include <linux/init.h> |
31 | #include <linux/blkdev.h> |
32 | #include <linux/parser.h> |
33 | #include <linux/crc32.h> |
34 | #include <linux/vfs.h> |
35 | #include <linux/writeback.h> |
36 | #include <linux/seq_file.h> |
37 | #include <linux/mount.h> |
38 | #include <linux/fs_context.h> |
39 | #include "nilfs.h" |
40 | #include "export.h" |
41 | #include "mdt.h" |
42 | #include "alloc.h" |
43 | #include "btree.h" |
44 | #include "btnode.h" |
45 | #include "page.h" |
46 | #include "cpfile.h" |
47 | #include "sufile.h" /* nilfs_sufile_resize(), nilfs_sufile_set_alloc_range() */ |
48 | #include "ifile.h" |
49 | #include "dat.h" |
50 | #include "segment.h" |
51 | #include "segbuf.h" |
52 | |
53 | MODULE_AUTHOR("NTT Corp." ); |
54 | MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem " |
55 | "(NILFS)" ); |
56 | MODULE_LICENSE("GPL" ); |
57 | |
58 | static struct kmem_cache *nilfs_inode_cachep; |
59 | struct kmem_cache *nilfs_transaction_cachep; |
60 | struct kmem_cache *nilfs_segbuf_cachep; |
61 | struct kmem_cache *nilfs_btree_path_cache; |
62 | |
63 | static int nilfs_setup_super(struct super_block *sb, int is_mount); |
64 | static int nilfs_remount(struct super_block *sb, int *flags, char *data); |
65 | |
66 | void __nilfs_msg(struct super_block *sb, const char *fmt, ...) |
67 | { |
68 | struct va_format vaf; |
69 | va_list args; |
70 | int level; |
71 | |
72 | va_start(args, fmt); |
73 | |
74 | level = printk_get_level(buffer: fmt); |
75 | vaf.fmt = printk_skip_level(buffer: fmt); |
76 | vaf.va = &args; |
77 | |
78 | if (sb) |
79 | printk("%c%cNILFS (%s): %pV\n" , |
80 | KERN_SOH_ASCII, level, sb->s_id, &vaf); |
81 | else |
82 | printk("%c%cNILFS: %pV\n" , |
83 | KERN_SOH_ASCII, level, &vaf); |
84 | |
85 | va_end(args); |
86 | } |
87 | |
88 | static void nilfs_set_error(struct super_block *sb) |
89 | { |
90 | struct the_nilfs *nilfs = sb->s_fs_info; |
91 | struct nilfs_super_block **sbp; |
92 | |
93 | down_write(sem: &nilfs->ns_sem); |
94 | if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) { |
95 | nilfs->ns_mount_state |= NILFS_ERROR_FS; |
96 | sbp = nilfs_prepare_super(sb, flip: 0); |
97 | if (likely(sbp)) { |
98 | sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS); |
99 | if (sbp[1]) |
100 | sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS); |
101 | nilfs_commit_super(sb, flag: NILFS_SB_COMMIT_ALL); |
102 | } |
103 | } |
104 | up_write(sem: &nilfs->ns_sem); |
105 | } |
106 | |
107 | /** |
108 | * __nilfs_error() - report failure condition on a filesystem |
109 | * |
110 | * __nilfs_error() sets an ERROR_FS flag on the superblock as well as |
111 | * reporting an error message. This function should be called when |
112 | * NILFS detects incoherences or defects of meta data on disk. |
113 | * |
114 | * This implements the body of nilfs_error() macro. Normally, |
115 | * nilfs_error() should be used. As for sustainable errors such as a |
116 | * single-shot I/O error, nilfs_err() should be used instead. |
117 | * |
118 | * Callers should not add a trailing newline since this will do it. |
119 | */ |
120 | void __nilfs_error(struct super_block *sb, const char *function, |
121 | const char *fmt, ...) |
122 | { |
123 | struct the_nilfs *nilfs = sb->s_fs_info; |
124 | struct va_format vaf; |
125 | va_list args; |
126 | |
127 | va_start(args, fmt); |
128 | |
129 | vaf.fmt = fmt; |
130 | vaf.va = &args; |
131 | |
132 | printk(KERN_CRIT "NILFS error (device %s): %s: %pV\n" , |
133 | sb->s_id, function, &vaf); |
134 | |
135 | va_end(args); |
136 | |
137 | if (!sb_rdonly(sb)) { |
138 | nilfs_set_error(sb); |
139 | |
140 | if (nilfs_test_opt(nilfs, ERRORS_RO)) { |
141 | printk(KERN_CRIT "Remounting filesystem read-only\n" ); |
142 | sb->s_flags |= SB_RDONLY; |
143 | } |
144 | } |
145 | |
146 | if (nilfs_test_opt(nilfs, ERRORS_PANIC)) |
147 | panic(fmt: "NILFS (device %s): panic forced after error\n" , |
148 | sb->s_id); |
149 | } |
150 | |
151 | struct inode *nilfs_alloc_inode(struct super_block *sb) |
152 | { |
153 | struct nilfs_inode_info *ii; |
154 | |
155 | ii = alloc_inode_sb(sb, cache: nilfs_inode_cachep, GFP_NOFS); |
156 | if (!ii) |
157 | return NULL; |
158 | ii->i_bh = NULL; |
159 | ii->i_state = 0; |
160 | ii->i_cno = 0; |
161 | ii->i_assoc_inode = NULL; |
162 | ii->i_bmap = &ii->i_bmap_data; |
163 | return &ii->vfs_inode; |
164 | } |
165 | |
166 | static void nilfs_free_inode(struct inode *inode) |
167 | { |
168 | if (nilfs_is_metadata_file_inode(inode)) |
169 | nilfs_mdt_destroy(inode); |
170 | |
171 | kmem_cache_free(s: nilfs_inode_cachep, objp: NILFS_I(inode)); |
172 | } |
173 | |
174 | static int nilfs_sync_super(struct super_block *sb, int flag) |
175 | { |
176 | struct the_nilfs *nilfs = sb->s_fs_info; |
177 | int err; |
178 | |
179 | retry: |
180 | set_buffer_dirty(nilfs->ns_sbh[0]); |
181 | if (nilfs_test_opt(nilfs, BARRIER)) { |
182 | err = __sync_dirty_buffer(bh: nilfs->ns_sbh[0], |
183 | REQ_SYNC | REQ_PREFLUSH | REQ_FUA); |
184 | } else { |
185 | err = sync_dirty_buffer(bh: nilfs->ns_sbh[0]); |
186 | } |
187 | |
188 | if (unlikely(err)) { |
189 | nilfs_err(sb, "unable to write superblock: err=%d" , err); |
190 | if (err == -EIO && nilfs->ns_sbh[1]) { |
191 | /* |
192 | * sbp[0] points to newer log than sbp[1], |
193 | * so copy sbp[0] to sbp[1] to take over sbp[0]. |
194 | */ |
195 | memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0], |
196 | nilfs->ns_sbsize); |
197 | nilfs_fall_back_super_block(nilfs); |
198 | goto retry; |
199 | } |
200 | } else { |
201 | struct nilfs_super_block *sbp = nilfs->ns_sbp[0]; |
202 | |
203 | nilfs->ns_sbwcount++; |
204 | |
205 | /* |
206 | * The latest segment becomes trailable from the position |
207 | * written in superblock. |
208 | */ |
209 | clear_nilfs_discontinued(nilfs); |
210 | |
211 | /* update GC protection for recent segments */ |
212 | if (nilfs->ns_sbh[1]) { |
213 | if (flag == NILFS_SB_COMMIT_ALL) { |
214 | set_buffer_dirty(nilfs->ns_sbh[1]); |
215 | if (sync_dirty_buffer(bh: nilfs->ns_sbh[1]) < 0) |
216 | goto out; |
217 | } |
218 | if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) < |
219 | le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno)) |
220 | sbp = nilfs->ns_sbp[1]; |
221 | } |
222 | |
223 | spin_lock(lock: &nilfs->ns_last_segment_lock); |
224 | nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq); |
225 | spin_unlock(lock: &nilfs->ns_last_segment_lock); |
226 | } |
227 | out: |
228 | return err; |
229 | } |
230 | |
231 | void nilfs_set_log_cursor(struct nilfs_super_block *sbp, |
232 | struct the_nilfs *nilfs) |
233 | { |
234 | sector_t nfreeblocks; |
235 | |
236 | /* nilfs->ns_sem must be locked by the caller. */ |
237 | nilfs_count_free_blocks(nilfs, &nfreeblocks); |
238 | sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks); |
239 | |
240 | spin_lock(lock: &nilfs->ns_last_segment_lock); |
241 | sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq); |
242 | sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg); |
243 | sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno); |
244 | spin_unlock(lock: &nilfs->ns_last_segment_lock); |
245 | } |
246 | |
247 | struct nilfs_super_block **nilfs_prepare_super(struct super_block *sb, |
248 | int flip) |
249 | { |
250 | struct the_nilfs *nilfs = sb->s_fs_info; |
251 | struct nilfs_super_block **sbp = nilfs->ns_sbp; |
252 | |
253 | /* nilfs->ns_sem must be locked by the caller. */ |
254 | if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { |
255 | if (sbp[1] && |
256 | sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) { |
257 | memcpy(sbp[0], sbp[1], nilfs->ns_sbsize); |
258 | } else { |
259 | nilfs_crit(sb, "superblock broke" ); |
260 | return NULL; |
261 | } |
262 | } else if (sbp[1] && |
263 | sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) { |
264 | memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); |
265 | } |
266 | |
267 | if (flip && sbp[1]) |
268 | nilfs_swap_super_block(nilfs); |
269 | |
270 | return sbp; |
271 | } |
272 | |
273 | int nilfs_commit_super(struct super_block *sb, int flag) |
274 | { |
275 | struct the_nilfs *nilfs = sb->s_fs_info; |
276 | struct nilfs_super_block **sbp = nilfs->ns_sbp; |
277 | time64_t t; |
278 | |
279 | /* nilfs->ns_sem must be locked by the caller. */ |
280 | t = ktime_get_real_seconds(); |
281 | nilfs->ns_sbwtime = t; |
282 | sbp[0]->s_wtime = cpu_to_le64(t); |
283 | sbp[0]->s_sum = 0; |
284 | sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, |
285 | (unsigned char *)sbp[0], |
286 | nilfs->ns_sbsize)); |
287 | if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) { |
288 | sbp[1]->s_wtime = sbp[0]->s_wtime; |
289 | sbp[1]->s_sum = 0; |
290 | sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed, |
291 | (unsigned char *)sbp[1], |
292 | nilfs->ns_sbsize)); |
293 | } |
294 | clear_nilfs_sb_dirty(nilfs); |
295 | nilfs->ns_flushed_device = 1; |
296 | /* make sure store to ns_flushed_device cannot be reordered */ |
297 | smp_wmb(); |
298 | return nilfs_sync_super(sb, flag); |
299 | } |
300 | |
301 | /** |
302 | * nilfs_cleanup_super() - write filesystem state for cleanup |
303 | * @sb: super block instance to be unmounted or degraded to read-only |
304 | * |
305 | * This function restores state flags in the on-disk super block. |
306 | * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the |
307 | * filesystem was not clean previously. |
308 | */ |
309 | int nilfs_cleanup_super(struct super_block *sb) |
310 | { |
311 | struct the_nilfs *nilfs = sb->s_fs_info; |
312 | struct nilfs_super_block **sbp; |
313 | int flag = NILFS_SB_COMMIT; |
314 | int ret = -EIO; |
315 | |
316 | sbp = nilfs_prepare_super(sb, flip: 0); |
317 | if (sbp) { |
318 | sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state); |
319 | nilfs_set_log_cursor(sbp: sbp[0], nilfs); |
320 | if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) { |
321 | /* |
322 | * make the "clean" flag also to the opposite |
323 | * super block if both super blocks point to |
324 | * the same checkpoint. |
325 | */ |
326 | sbp[1]->s_state = sbp[0]->s_state; |
327 | flag = NILFS_SB_COMMIT_ALL; |
328 | } |
329 | ret = nilfs_commit_super(sb, flag); |
330 | } |
331 | return ret; |
332 | } |
333 | |
334 | /** |
335 | * nilfs_move_2nd_super - relocate secondary super block |
336 | * @sb: super block instance |
337 | * @sb2off: new offset of the secondary super block (in bytes) |
338 | */ |
339 | static int nilfs_move_2nd_super(struct super_block *sb, loff_t sb2off) |
340 | { |
341 | struct the_nilfs *nilfs = sb->s_fs_info; |
342 | struct buffer_head *nsbh; |
343 | struct nilfs_super_block *nsbp; |
344 | sector_t blocknr, newblocknr; |
345 | unsigned long offset; |
346 | int sb2i; /* array index of the secondary superblock */ |
347 | int ret = 0; |
348 | |
349 | /* nilfs->ns_sem must be locked by the caller. */ |
350 | if (nilfs->ns_sbh[1] && |
351 | nilfs->ns_sbh[1]->b_blocknr > nilfs->ns_first_data_block) { |
352 | sb2i = 1; |
353 | blocknr = nilfs->ns_sbh[1]->b_blocknr; |
354 | } else if (nilfs->ns_sbh[0]->b_blocknr > nilfs->ns_first_data_block) { |
355 | sb2i = 0; |
356 | blocknr = nilfs->ns_sbh[0]->b_blocknr; |
357 | } else { |
358 | sb2i = -1; |
359 | blocknr = 0; |
360 | } |
361 | if (sb2i >= 0 && (u64)blocknr << nilfs->ns_blocksize_bits == sb2off) |
362 | goto out; /* super block location is unchanged */ |
363 | |
364 | /* Get new super block buffer */ |
365 | newblocknr = sb2off >> nilfs->ns_blocksize_bits; |
366 | offset = sb2off & (nilfs->ns_blocksize - 1); |
367 | nsbh = sb_getblk(sb, block: newblocknr); |
368 | if (!nsbh) { |
369 | nilfs_warn(sb, |
370 | "unable to move secondary superblock to block %llu" , |
371 | (unsigned long long)newblocknr); |
372 | ret = -EIO; |
373 | goto out; |
374 | } |
375 | nsbp = (void *)nsbh->b_data + offset; |
376 | |
377 | lock_buffer(bh: nsbh); |
378 | if (sb2i >= 0) { |
379 | /* |
380 | * The position of the second superblock only changes by 4KiB, |
381 | * which is larger than the maximum superblock data size |
382 | * (= 1KiB), so there is no need to use memmove() to allow |
383 | * overlap between source and destination. |
384 | */ |
385 | memcpy(nsbp, nilfs->ns_sbp[sb2i], nilfs->ns_sbsize); |
386 | |
387 | /* |
388 | * Zero fill after copy to avoid overwriting in case of move |
389 | * within the same block. |
390 | */ |
391 | memset(nsbh->b_data, 0, offset); |
392 | memset((void *)nsbp + nilfs->ns_sbsize, 0, |
393 | nsbh->b_size - offset - nilfs->ns_sbsize); |
394 | } else { |
395 | memset(nsbh->b_data, 0, nsbh->b_size); |
396 | } |
397 | set_buffer_uptodate(nsbh); |
398 | unlock_buffer(bh: nsbh); |
399 | |
400 | if (sb2i >= 0) { |
401 | brelse(bh: nilfs->ns_sbh[sb2i]); |
402 | nilfs->ns_sbh[sb2i] = nsbh; |
403 | nilfs->ns_sbp[sb2i] = nsbp; |
404 | } else if (nilfs->ns_sbh[0]->b_blocknr < nilfs->ns_first_data_block) { |
405 | /* secondary super block will be restored to index 1 */ |
406 | nilfs->ns_sbh[1] = nsbh; |
407 | nilfs->ns_sbp[1] = nsbp; |
408 | } else { |
409 | brelse(bh: nsbh); |
410 | } |
411 | out: |
412 | return ret; |
413 | } |
414 | |
415 | /** |
416 | * nilfs_resize_fs - resize the filesystem |
417 | * @sb: super block instance |
418 | * @newsize: new size of the filesystem (in bytes) |
419 | */ |
420 | int nilfs_resize_fs(struct super_block *sb, __u64 newsize) |
421 | { |
422 | struct the_nilfs *nilfs = sb->s_fs_info; |
423 | struct nilfs_super_block **sbp; |
424 | __u64 devsize, newnsegs; |
425 | loff_t sb2off; |
426 | int ret; |
427 | |
428 | ret = -ERANGE; |
429 | devsize = bdev_nr_bytes(bdev: sb->s_bdev); |
430 | if (newsize > devsize) |
431 | goto out; |
432 | |
433 | /* |
434 | * Prevent underflow in second superblock position calculation. |
435 | * The exact minimum size check is done in nilfs_sufile_resize(). |
436 | */ |
437 | if (newsize < 4096) { |
438 | ret = -ENOSPC; |
439 | goto out; |
440 | } |
441 | |
442 | /* |
443 | * Write lock is required to protect some functions depending |
444 | * on the number of segments, the number of reserved segments, |
445 | * and so forth. |
446 | */ |
447 | down_write(sem: &nilfs->ns_segctor_sem); |
448 | |
449 | sb2off = NILFS_SB2_OFFSET_BYTES(newsize); |
450 | newnsegs = sb2off >> nilfs->ns_blocksize_bits; |
451 | newnsegs = div64_ul(newnsegs, nilfs->ns_blocks_per_segment); |
452 | |
453 | ret = nilfs_sufile_resize(sufile: nilfs->ns_sufile, newnsegs); |
454 | up_write(sem: &nilfs->ns_segctor_sem); |
455 | if (ret < 0) |
456 | goto out; |
457 | |
458 | ret = nilfs_construct_segment(sb); |
459 | if (ret < 0) |
460 | goto out; |
461 | |
462 | down_write(sem: &nilfs->ns_sem); |
463 | nilfs_move_2nd_super(sb, sb2off); |
464 | ret = -EIO; |
465 | sbp = nilfs_prepare_super(sb, flip: 0); |
466 | if (likely(sbp)) { |
467 | nilfs_set_log_cursor(sbp: sbp[0], nilfs); |
468 | /* |
469 | * Drop NILFS_RESIZE_FS flag for compatibility with |
470 | * mount-time resize which may be implemented in a |
471 | * future release. |
472 | */ |
473 | sbp[0]->s_state = cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & |
474 | ~NILFS_RESIZE_FS); |
475 | sbp[0]->s_dev_size = cpu_to_le64(newsize); |
476 | sbp[0]->s_nsegments = cpu_to_le64(nilfs->ns_nsegments); |
477 | if (sbp[1]) |
478 | memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); |
479 | ret = nilfs_commit_super(sb, flag: NILFS_SB_COMMIT_ALL); |
480 | } |
481 | up_write(sem: &nilfs->ns_sem); |
482 | |
483 | /* |
484 | * Reset the range of allocatable segments last. This order |
485 | * is important in the case of expansion because the secondary |
486 | * superblock must be protected from log write until migration |
487 | * completes. |
488 | */ |
489 | if (!ret) |
490 | nilfs_sufile_set_alloc_range(sufile: nilfs->ns_sufile, start: 0, end: newnsegs - 1); |
491 | out: |
492 | return ret; |
493 | } |
494 | |
495 | static void nilfs_put_super(struct super_block *sb) |
496 | { |
497 | struct the_nilfs *nilfs = sb->s_fs_info; |
498 | |
499 | nilfs_detach_log_writer(sb); |
500 | |
501 | if (!sb_rdonly(sb)) { |
502 | down_write(sem: &nilfs->ns_sem); |
503 | nilfs_cleanup_super(sb); |
504 | up_write(sem: &nilfs->ns_sem); |
505 | } |
506 | |
507 | nilfs_sysfs_delete_device_group(nilfs); |
508 | iput(nilfs->ns_sufile); |
509 | iput(nilfs->ns_cpfile); |
510 | iput(nilfs->ns_dat); |
511 | |
512 | destroy_nilfs(nilfs); |
513 | sb->s_fs_info = NULL; |
514 | } |
515 | |
516 | static int nilfs_sync_fs(struct super_block *sb, int wait) |
517 | { |
518 | struct the_nilfs *nilfs = sb->s_fs_info; |
519 | struct nilfs_super_block **sbp; |
520 | int err = 0; |
521 | |
522 | /* This function is called when super block should be written back */ |
523 | if (wait) |
524 | err = nilfs_construct_segment(sb); |
525 | |
526 | down_write(sem: &nilfs->ns_sem); |
527 | if (nilfs_sb_dirty(nilfs)) { |
528 | sbp = nilfs_prepare_super(sb, flip: nilfs_sb_will_flip(nilfs)); |
529 | if (likely(sbp)) { |
530 | nilfs_set_log_cursor(sbp: sbp[0], nilfs); |
531 | nilfs_commit_super(sb, flag: NILFS_SB_COMMIT); |
532 | } |
533 | } |
534 | up_write(sem: &nilfs->ns_sem); |
535 | |
536 | if (!err) |
537 | err = nilfs_flush_device(nilfs); |
538 | |
539 | return err; |
540 | } |
541 | |
542 | int nilfs_attach_checkpoint(struct super_block *sb, __u64 cno, int curr_mnt, |
543 | struct nilfs_root **rootp) |
544 | { |
545 | struct the_nilfs *nilfs = sb->s_fs_info; |
546 | struct nilfs_root *root; |
547 | int err = -ENOMEM; |
548 | |
549 | root = nilfs_find_or_create_root( |
550 | nilfs, cno: curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno); |
551 | if (!root) |
552 | return err; |
553 | |
554 | if (root->ifile) |
555 | goto reuse; /* already attached checkpoint */ |
556 | |
557 | down_read(sem: &nilfs->ns_segctor_sem); |
558 | err = nilfs_ifile_read(sb, root, cno, inode_size: nilfs->ns_inode_size); |
559 | up_read(sem: &nilfs->ns_segctor_sem); |
560 | if (unlikely(err)) |
561 | goto failed; |
562 | |
563 | reuse: |
564 | *rootp = root; |
565 | return 0; |
566 | |
567 | failed: |
568 | if (err == -EINVAL) |
569 | nilfs_err(sb, "Invalid checkpoint (checkpoint number=%llu)" , |
570 | (unsigned long long)cno); |
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_rdonly(sb)) |
582 | return 0; |
583 | |
584 | /* Mark super block clean */ |
585 | down_write(sem: &nilfs->ns_sem); |
586 | err = nilfs_cleanup_super(sb); |
587 | up_write(sem: &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_rdonly(sb)) |
596 | return 0; |
597 | |
598 | down_write(sem: &nilfs->ns_sem); |
599 | nilfs_setup_super(sb, is_mount: false); |
600 | up_write(sem: &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(inode: d_inode(dentry))->i_root; |
608 | struct the_nilfs *nilfs = root->nilfs; |
609 | u64 id = huge_encode_dev(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_warn(sb, "failed to count free inodes: err=%d" , err); |
643 | if (err == -ERANGE) { |
644 | /* |
645 | * If nilfs_palloc_count_max_entries() returns |
646 | * -ERANGE error code then we simply treat |
647 | * curent inodes count as maximum possible and |
648 | * zero as free inodes value. |
649 | */ |
650 | nmaxinodes = atomic64_read(v: &root->inodes_count); |
651 | nfreeinodes = 0; |
652 | err = 0; |
653 | } else |
654 | return err; |
655 | } |
656 | |
657 | buf->f_type = NILFS_SUPER_MAGIC; |
658 | buf->f_bsize = sb->s_blocksize; |
659 | buf->f_blocks = blocks - overhead; |
660 | buf->f_bfree = nfreeblocks; |
661 | buf->f_bavail = (buf->f_bfree >= nrsvblocks) ? |
662 | (buf->f_bfree - nrsvblocks) : 0; |
663 | buf->f_files = nmaxinodes; |
664 | buf->f_ffree = nfreeinodes; |
665 | buf->f_namelen = NILFS_NAME_LEN; |
666 | buf->f_fsid = u64_to_fsid(v: id); |
667 | |
668 | return 0; |
669 | } |
670 | |
671 | static int nilfs_show_options(struct seq_file *seq, struct dentry *dentry) |
672 | { |
673 | struct super_block *sb = dentry->d_sb; |
674 | struct the_nilfs *nilfs = sb->s_fs_info; |
675 | struct nilfs_root *root = NILFS_I(inode: d_inode(dentry))->i_root; |
676 | |
677 | if (!nilfs_test_opt(nilfs, BARRIER)) |
678 | seq_puts(m: seq, s: ",nobarrier" ); |
679 | if (root->cno != NILFS_CPTREE_CURRENT_CNO) |
680 | seq_printf(m: seq, fmt: ",cp=%llu" , (unsigned long long)root->cno); |
681 | if (nilfs_test_opt(nilfs, ERRORS_PANIC)) |
682 | seq_puts(m: seq, s: ",errors=panic" ); |
683 | if (nilfs_test_opt(nilfs, ERRORS_CONT)) |
684 | seq_puts(m: seq, s: ",errors=continue" ); |
685 | if (nilfs_test_opt(nilfs, STRICT_ORDER)) |
686 | seq_puts(m: seq, s: ",order=strict" ); |
687 | if (nilfs_test_opt(nilfs, NORECOVERY)) |
688 | seq_puts(m: seq, s: ",norecovery" ); |
689 | if (nilfs_test_opt(nilfs, DISCARD)) |
690 | seq_puts(m: seq, s: ",discard" ); |
691 | |
692 | return 0; |
693 | } |
694 | |
695 | static const struct super_operations nilfs_sops = { |
696 | .alloc_inode = nilfs_alloc_inode, |
697 | .free_inode = nilfs_free_inode, |
698 | .dirty_inode = nilfs_dirty_inode, |
699 | .evict_inode = nilfs_evict_inode, |
700 | .put_super = nilfs_put_super, |
701 | .sync_fs = nilfs_sync_fs, |
702 | .freeze_fs = nilfs_freeze, |
703 | .unfreeze_fs = nilfs_unfreeze, |
704 | .statfs = nilfs_statfs, |
705 | .remount_fs = nilfs_remount, |
706 | .show_options = nilfs_show_options |
707 | }; |
708 | |
709 | enum { |
710 | Opt_err_cont, Opt_err_panic, Opt_err_ro, |
711 | Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery, |
712 | Opt_discard, Opt_nodiscard, Opt_err, |
713 | }; |
714 | |
715 | static match_table_t tokens = { |
716 | {Opt_err_cont, "errors=continue" }, |
717 | {Opt_err_panic, "errors=panic" }, |
718 | {Opt_err_ro, "errors=remount-ro" }, |
719 | {Opt_barrier, "barrier" }, |
720 | {Opt_nobarrier, "nobarrier" }, |
721 | {Opt_snapshot, "cp=%u" }, |
722 | {Opt_order, "order=%s" }, |
723 | {Opt_norecovery, "norecovery" }, |
724 | {Opt_discard, "discard" }, |
725 | {Opt_nodiscard, "nodiscard" }, |
726 | {Opt_err, NULL} |
727 | }; |
728 | |
729 | static int parse_options(char *options, struct super_block *sb, int is_remount) |
730 | { |
731 | struct the_nilfs *nilfs = sb->s_fs_info; |
732 | char *p; |
733 | substring_t args[MAX_OPT_ARGS]; |
734 | |
735 | if (!options) |
736 | return 1; |
737 | |
738 | while ((p = strsep(&options, "," )) != NULL) { |
739 | int token; |
740 | |
741 | if (!*p) |
742 | continue; |
743 | |
744 | token = match_token(p, table: tokens, args); |
745 | switch (token) { |
746 | case Opt_barrier: |
747 | nilfs_set_opt(nilfs, BARRIER); |
748 | break; |
749 | case Opt_nobarrier: |
750 | nilfs_clear_opt(nilfs, BARRIER); |
751 | break; |
752 | case Opt_order: |
753 | if (strcmp(args[0].from, "relaxed" ) == 0) |
754 | /* Ordered data semantics */ |
755 | nilfs_clear_opt(nilfs, STRICT_ORDER); |
756 | else if (strcmp(args[0].from, "strict" ) == 0) |
757 | /* Strict in-order semantics */ |
758 | nilfs_set_opt(nilfs, STRICT_ORDER); |
759 | else |
760 | return 0; |
761 | break; |
762 | case Opt_err_panic: |
763 | nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_PANIC); |
764 | break; |
765 | case Opt_err_ro: |
766 | nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_RO); |
767 | break; |
768 | case Opt_err_cont: |
769 | nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_CONT); |
770 | break; |
771 | case Opt_snapshot: |
772 | if (is_remount) { |
773 | nilfs_err(sb, |
774 | "\"%s\" option is invalid for remount" , |
775 | p); |
776 | return 0; |
777 | } |
778 | break; |
779 | case Opt_norecovery: |
780 | nilfs_set_opt(nilfs, NORECOVERY); |
781 | break; |
782 | case Opt_discard: |
783 | nilfs_set_opt(nilfs, DISCARD); |
784 | break; |
785 | case Opt_nodiscard: |
786 | nilfs_clear_opt(nilfs, DISCARD); |
787 | break; |
788 | default: |
789 | nilfs_err(sb, "unrecognized mount option \"%s\"" , p); |
790 | return 0; |
791 | } |
792 | } |
793 | return 1; |
794 | } |
795 | |
796 | static inline void |
797 | nilfs_set_default_options(struct super_block *sb, |
798 | struct nilfs_super_block *sbp) |
799 | { |
800 | struct the_nilfs *nilfs = sb->s_fs_info; |
801 | |
802 | nilfs->ns_mount_opt = |
803 | NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER; |
804 | } |
805 | |
806 | static int nilfs_setup_super(struct super_block *sb, int is_mount) |
807 | { |
808 | struct the_nilfs *nilfs = sb->s_fs_info; |
809 | struct nilfs_super_block **sbp; |
810 | int max_mnt_count; |
811 | int mnt_count; |
812 | |
813 | /* nilfs->ns_sem must be locked by the caller. */ |
814 | sbp = nilfs_prepare_super(sb, flip: 0); |
815 | if (!sbp) |
816 | return -EIO; |
817 | |
818 | if (!is_mount) |
819 | goto skip_mount_setup; |
820 | |
821 | max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count); |
822 | mnt_count = le16_to_cpu(sbp[0]->s_mnt_count); |
823 | |
824 | if (nilfs->ns_mount_state & NILFS_ERROR_FS) { |
825 | nilfs_warn(sb, "mounting fs with errors" ); |
826 | #if 0 |
827 | } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) { |
828 | nilfs_warn(sb, "maximal mount count reached" ); |
829 | #endif |
830 | } |
831 | if (!max_mnt_count) |
832 | sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT); |
833 | |
834 | sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1); |
835 | sbp[0]->s_mtime = cpu_to_le64(ktime_get_real_seconds()); |
836 | |
837 | skip_mount_setup: |
838 | sbp[0]->s_state = |
839 | cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS); |
840 | /* synchronize sbp[1] with sbp[0] */ |
841 | if (sbp[1]) |
842 | memcpy(sbp[1], sbp[0], nilfs->ns_sbsize); |
843 | return nilfs_commit_super(sb, flag: NILFS_SB_COMMIT_ALL); |
844 | } |
845 | |
846 | struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb, |
847 | u64 pos, int blocksize, |
848 | struct buffer_head **pbh) |
849 | { |
850 | unsigned long long sb_index = pos; |
851 | unsigned long offset; |
852 | |
853 | offset = do_div(sb_index, blocksize); |
854 | *pbh = sb_bread(sb, block: sb_index); |
855 | if (!*pbh) |
856 | return NULL; |
857 | return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset); |
858 | } |
859 | |
860 | int nilfs_store_magic_and_option(struct super_block *sb, |
861 | struct nilfs_super_block *sbp, |
862 | char *data) |
863 | { |
864 | struct the_nilfs *nilfs = sb->s_fs_info; |
865 | |
866 | sb->s_magic = le16_to_cpu(sbp->s_magic); |
867 | |
868 | /* FS independent flags */ |
869 | #ifdef NILFS_ATIME_DISABLE |
870 | sb->s_flags |= SB_NOATIME; |
871 | #endif |
872 | |
873 | nilfs_set_default_options(sb, sbp); |
874 | |
875 | nilfs->ns_resuid = le16_to_cpu(sbp->s_def_resuid); |
876 | nilfs->ns_resgid = le16_to_cpu(sbp->s_def_resgid); |
877 | nilfs->ns_interval = le32_to_cpu(sbp->s_c_interval); |
878 | nilfs->ns_watermark = le32_to_cpu(sbp->s_c_block_max); |
879 | |
880 | return !parse_options(options: data, sb, is_remount: 0) ? -EINVAL : 0; |
881 | } |
882 | |
883 | int nilfs_check_feature_compatibility(struct super_block *sb, |
884 | struct nilfs_super_block *sbp) |
885 | { |
886 | __u64 features; |
887 | |
888 | features = le64_to_cpu(sbp->s_feature_incompat) & |
889 | ~NILFS_FEATURE_INCOMPAT_SUPP; |
890 | if (features) { |
891 | nilfs_err(sb, |
892 | "couldn't mount because of unsupported optional features (%llx)" , |
893 | (unsigned long long)features); |
894 | return -EINVAL; |
895 | } |
896 | features = le64_to_cpu(sbp->s_feature_compat_ro) & |
897 | ~NILFS_FEATURE_COMPAT_RO_SUPP; |
898 | if (!sb_rdonly(sb) && features) { |
899 | nilfs_err(sb, |
900 | "couldn't mount RDWR because of unsupported optional features (%llx)" , |
901 | (unsigned long long)features); |
902 | return -EINVAL; |
903 | } |
904 | return 0; |
905 | } |
906 | |
907 | static int nilfs_get_root_dentry(struct super_block *sb, |
908 | struct nilfs_root *root, |
909 | struct dentry **root_dentry) |
910 | { |
911 | struct inode *inode; |
912 | struct dentry *dentry; |
913 | int ret = 0; |
914 | |
915 | inode = nilfs_iget(sb, root, NILFS_ROOT_INO); |
916 | if (IS_ERR(ptr: inode)) { |
917 | ret = PTR_ERR(ptr: inode); |
918 | nilfs_err(sb, "error %d getting root inode" , ret); |
919 | goto out; |
920 | } |
921 | if (!S_ISDIR(inode->i_mode) || !inode->i_blocks || !inode->i_size) { |
922 | iput(inode); |
923 | nilfs_err(sb, "corrupt root inode" ); |
924 | ret = -EINVAL; |
925 | goto out; |
926 | } |
927 | |
928 | if (root->cno == NILFS_CPTREE_CURRENT_CNO) { |
929 | dentry = d_find_alias(inode); |
930 | if (!dentry) { |
931 | dentry = d_make_root(inode); |
932 | if (!dentry) { |
933 | ret = -ENOMEM; |
934 | goto failed_dentry; |
935 | } |
936 | } else { |
937 | iput(inode); |
938 | } |
939 | } else { |
940 | dentry = d_obtain_root(inode); |
941 | if (IS_ERR(ptr: dentry)) { |
942 | ret = PTR_ERR(ptr: dentry); |
943 | goto failed_dentry; |
944 | } |
945 | } |
946 | *root_dentry = dentry; |
947 | out: |
948 | return ret; |
949 | |
950 | failed_dentry: |
951 | nilfs_err(sb, "error %d getting root dentry" , ret); |
952 | goto out; |
953 | } |
954 | |
955 | static int nilfs_attach_snapshot(struct super_block *s, __u64 cno, |
956 | struct dentry **root_dentry) |
957 | { |
958 | struct the_nilfs *nilfs = s->s_fs_info; |
959 | struct nilfs_root *root; |
960 | int ret; |
961 | |
962 | mutex_lock(&nilfs->ns_snapshot_mount_mutex); |
963 | |
964 | down_read(sem: &nilfs->ns_segctor_sem); |
965 | ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno); |
966 | up_read(sem: &nilfs->ns_segctor_sem); |
967 | if (ret < 0) { |
968 | ret = (ret == -ENOENT) ? -EINVAL : ret; |
969 | goto out; |
970 | } else if (!ret) { |
971 | nilfs_err(s, |
972 | "The specified checkpoint is not a snapshot (checkpoint number=%llu)" , |
973 | (unsigned long long)cno); |
974 | ret = -EINVAL; |
975 | goto out; |
976 | } |
977 | |
978 | ret = nilfs_attach_checkpoint(sb: s, cno, curr_mnt: false, rootp: &root); |
979 | if (ret) { |
980 | nilfs_err(s, |
981 | "error %d while loading snapshot (checkpoint number=%llu)" , |
982 | ret, (unsigned long long)cno); |
983 | goto out; |
984 | } |
985 | ret = nilfs_get_root_dentry(sb: s, root, root_dentry); |
986 | nilfs_put_root(root); |
987 | out: |
988 | mutex_unlock(lock: &nilfs->ns_snapshot_mount_mutex); |
989 | return ret; |
990 | } |
991 | |
992 | /** |
993 | * nilfs_tree_is_busy() - try to shrink dentries of a checkpoint |
994 | * @root_dentry: root dentry of the tree to be shrunk |
995 | * |
996 | * This function returns true if the tree was in-use. |
997 | */ |
998 | static bool nilfs_tree_is_busy(struct dentry *root_dentry) |
999 | { |
1000 | shrink_dcache_parent(root_dentry); |
1001 | return d_count(dentry: root_dentry) > 1; |
1002 | } |
1003 | |
1004 | int nilfs_checkpoint_is_mounted(struct super_block *sb, __u64 cno) |
1005 | { |
1006 | struct the_nilfs *nilfs = sb->s_fs_info; |
1007 | struct nilfs_root *root; |
1008 | struct inode *inode; |
1009 | struct dentry *dentry; |
1010 | int ret; |
1011 | |
1012 | if (cno > nilfs->ns_cno) |
1013 | return false; |
1014 | |
1015 | if (cno >= nilfs_last_cno(nilfs)) |
1016 | return true; /* protect recent checkpoints */ |
1017 | |
1018 | ret = false; |
1019 | root = nilfs_lookup_root(nilfs, cno); |
1020 | if (root) { |
1021 | inode = nilfs_ilookup(sb, root, NILFS_ROOT_INO); |
1022 | if (inode) { |
1023 | dentry = d_find_alias(inode); |
1024 | if (dentry) { |
1025 | ret = nilfs_tree_is_busy(root_dentry: dentry); |
1026 | dput(dentry); |
1027 | } |
1028 | iput(inode); |
1029 | } |
1030 | nilfs_put_root(root); |
1031 | } |
1032 | return ret; |
1033 | } |
1034 | |
1035 | /** |
1036 | * nilfs_fill_super() - initialize a super block instance |
1037 | * @sb: super_block |
1038 | * @data: mount options |
1039 | * @silent: silent mode flag |
1040 | * |
1041 | * This function is called exclusively by nilfs->ns_mount_mutex. |
1042 | * So, the recovery process is protected from other simultaneous mounts. |
1043 | */ |
1044 | static int |
1045 | nilfs_fill_super(struct super_block *sb, void *data, int silent) |
1046 | { |
1047 | struct the_nilfs *nilfs; |
1048 | struct nilfs_root *fsroot; |
1049 | __u64 cno; |
1050 | int err; |
1051 | |
1052 | nilfs = alloc_nilfs(sb); |
1053 | if (!nilfs) |
1054 | return -ENOMEM; |
1055 | |
1056 | sb->s_fs_info = nilfs; |
1057 | |
1058 | err = init_nilfs(nilfs, sb, data: (char *)data); |
1059 | if (err) |
1060 | goto failed_nilfs; |
1061 | |
1062 | sb->s_op = &nilfs_sops; |
1063 | sb->s_export_op = &nilfs_export_ops; |
1064 | sb->s_root = NULL; |
1065 | sb->s_time_gran = 1; |
1066 | sb->s_max_links = NILFS_LINK_MAX; |
1067 | |
1068 | sb->s_bdi = bdi_get(bdi: sb->s_bdev->bd_disk->bdi); |
1069 | |
1070 | err = load_nilfs(nilfs, sb); |
1071 | if (err) |
1072 | goto failed_nilfs; |
1073 | |
1074 | cno = nilfs_last_cno(nilfs); |
1075 | err = nilfs_attach_checkpoint(sb, cno, curr_mnt: true, rootp: &fsroot); |
1076 | if (err) { |
1077 | nilfs_err(sb, |
1078 | "error %d while loading last checkpoint (checkpoint number=%llu)" , |
1079 | err, (unsigned long long)cno); |
1080 | goto failed_unload; |
1081 | } |
1082 | |
1083 | if (!sb_rdonly(sb)) { |
1084 | err = nilfs_attach_log_writer(sb, root: fsroot); |
1085 | if (err) |
1086 | goto failed_checkpoint; |
1087 | } |
1088 | |
1089 | err = nilfs_get_root_dentry(sb, root: fsroot, root_dentry: &sb->s_root); |
1090 | if (err) |
1091 | goto failed_segctor; |
1092 | |
1093 | nilfs_put_root(root: fsroot); |
1094 | |
1095 | if (!sb_rdonly(sb)) { |
1096 | down_write(sem: &nilfs->ns_sem); |
1097 | nilfs_setup_super(sb, is_mount: true); |
1098 | up_write(sem: &nilfs->ns_sem); |
1099 | } |
1100 | |
1101 | return 0; |
1102 | |
1103 | failed_segctor: |
1104 | nilfs_detach_log_writer(sb); |
1105 | |
1106 | failed_checkpoint: |
1107 | nilfs_put_root(root: fsroot); |
1108 | |
1109 | failed_unload: |
1110 | nilfs_sysfs_delete_device_group(nilfs); |
1111 | iput(nilfs->ns_sufile); |
1112 | iput(nilfs->ns_cpfile); |
1113 | iput(nilfs->ns_dat); |
1114 | |
1115 | failed_nilfs: |
1116 | destroy_nilfs(nilfs); |
1117 | return err; |
1118 | } |
1119 | |
1120 | static int nilfs_remount(struct super_block *sb, int *flags, char *data) |
1121 | { |
1122 | struct the_nilfs *nilfs = sb->s_fs_info; |
1123 | unsigned long old_sb_flags; |
1124 | unsigned long old_mount_opt; |
1125 | int err; |
1126 | |
1127 | sync_filesystem(sb); |
1128 | old_sb_flags = sb->s_flags; |
1129 | old_mount_opt = nilfs->ns_mount_opt; |
1130 | |
1131 | if (!parse_options(options: data, sb, is_remount: 1)) { |
1132 | err = -EINVAL; |
1133 | goto restore_opts; |
1134 | } |
1135 | sb->s_flags = (sb->s_flags & ~SB_POSIXACL); |
1136 | |
1137 | err = -EINVAL; |
1138 | |
1139 | if (!nilfs_valid_fs(nilfs)) { |
1140 | nilfs_warn(sb, |
1141 | "couldn't remount because the filesystem is in an incomplete recovery state" ); |
1142 | goto restore_opts; |
1143 | } |
1144 | |
1145 | if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) |
1146 | goto out; |
1147 | if (*flags & SB_RDONLY) { |
1148 | sb->s_flags |= SB_RDONLY; |
1149 | |
1150 | /* |
1151 | * Remounting a valid RW partition RDONLY, so set |
1152 | * the RDONLY flag and then mark the partition as valid again. |
1153 | */ |
1154 | down_write(sem: &nilfs->ns_sem); |
1155 | nilfs_cleanup_super(sb); |
1156 | up_write(sem: &nilfs->ns_sem); |
1157 | } else { |
1158 | __u64 features; |
1159 | struct nilfs_root *root; |
1160 | |
1161 | /* |
1162 | * Mounting a RDONLY partition read-write, so reread and |
1163 | * store the current valid flag. (It may have been changed |
1164 | * by fsck since we originally mounted the partition.) |
1165 | */ |
1166 | down_read(sem: &nilfs->ns_sem); |
1167 | features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) & |
1168 | ~NILFS_FEATURE_COMPAT_RO_SUPP; |
1169 | up_read(sem: &nilfs->ns_sem); |
1170 | if (features) { |
1171 | nilfs_warn(sb, |
1172 | "couldn't remount RDWR because of unsupported optional features (%llx)" , |
1173 | (unsigned long long)features); |
1174 | err = -EROFS; |
1175 | goto restore_opts; |
1176 | } |
1177 | |
1178 | sb->s_flags &= ~SB_RDONLY; |
1179 | |
1180 | root = NILFS_I(inode: d_inode(dentry: sb->s_root))->i_root; |
1181 | err = nilfs_attach_log_writer(sb, root); |
1182 | if (err) |
1183 | goto restore_opts; |
1184 | |
1185 | down_write(sem: &nilfs->ns_sem); |
1186 | nilfs_setup_super(sb, is_mount: true); |
1187 | up_write(sem: &nilfs->ns_sem); |
1188 | } |
1189 | out: |
1190 | return 0; |
1191 | |
1192 | restore_opts: |
1193 | sb->s_flags = old_sb_flags; |
1194 | nilfs->ns_mount_opt = old_mount_opt; |
1195 | return err; |
1196 | } |
1197 | |
1198 | struct nilfs_super_data { |
1199 | __u64 cno; |
1200 | int flags; |
1201 | }; |
1202 | |
1203 | static int nilfs_parse_snapshot_option(const char *option, |
1204 | const substring_t *arg, |
1205 | struct nilfs_super_data *sd) |
1206 | { |
1207 | unsigned long long val; |
1208 | const char *msg = NULL; |
1209 | int err; |
1210 | |
1211 | if (!(sd->flags & SB_RDONLY)) { |
1212 | msg = "read-only option is not specified" ; |
1213 | goto parse_error; |
1214 | } |
1215 | |
1216 | err = kstrtoull(s: arg->from, base: 0, res: &val); |
1217 | if (err) { |
1218 | if (err == -ERANGE) |
1219 | msg = "too large checkpoint number" ; |
1220 | else |
1221 | msg = "malformed argument" ; |
1222 | goto parse_error; |
1223 | } else if (val == 0) { |
1224 | msg = "invalid checkpoint number 0" ; |
1225 | goto parse_error; |
1226 | } |
1227 | sd->cno = val; |
1228 | return 0; |
1229 | |
1230 | parse_error: |
1231 | nilfs_err(NULL, "invalid option \"%s\": %s" , option, msg); |
1232 | return 1; |
1233 | } |
1234 | |
1235 | /** |
1236 | * nilfs_identify - pre-read mount options needed to identify mount instance |
1237 | * @data: mount options |
1238 | * @sd: nilfs_super_data |
1239 | */ |
1240 | static int nilfs_identify(char *data, struct nilfs_super_data *sd) |
1241 | { |
1242 | char *p, *options = data; |
1243 | substring_t args[MAX_OPT_ARGS]; |
1244 | int token; |
1245 | int ret = 0; |
1246 | |
1247 | do { |
1248 | p = strsep(&options, "," ); |
1249 | if (p != NULL && *p) { |
1250 | token = match_token(p, table: tokens, args); |
1251 | if (token == Opt_snapshot) |
1252 | ret = nilfs_parse_snapshot_option(option: p, arg: &args[0], |
1253 | sd); |
1254 | } |
1255 | if (!options) |
1256 | break; |
1257 | BUG_ON(options == data); |
1258 | *(options - 1) = ','; |
1259 | } while (!ret); |
1260 | return ret; |
1261 | } |
1262 | |
1263 | static int nilfs_set_bdev_super(struct super_block *s, void *data) |
1264 | { |
1265 | s->s_dev = *(dev_t *)data; |
1266 | return 0; |
1267 | } |
1268 | |
1269 | static int nilfs_test_bdev_super(struct super_block *s, void *data) |
1270 | { |
1271 | return !(s->s_iflags & SB_I_RETIRED) && s->s_dev == *(dev_t *)data; |
1272 | } |
1273 | |
1274 | static struct dentry * |
1275 | nilfs_mount(struct file_system_type *fs_type, int flags, |
1276 | const char *dev_name, void *data) |
1277 | { |
1278 | struct nilfs_super_data sd = { .flags = flags }; |
1279 | struct super_block *s; |
1280 | dev_t dev; |
1281 | int err; |
1282 | |
1283 | if (nilfs_identify(data, sd: &sd)) |
1284 | return ERR_PTR(error: -EINVAL); |
1285 | |
1286 | err = lookup_bdev(pathname: dev_name, dev: &dev); |
1287 | if (err) |
1288 | return ERR_PTR(error: err); |
1289 | |
1290 | s = sget(type: fs_type, test: nilfs_test_bdev_super, set: nilfs_set_bdev_super, flags, |
1291 | data: &dev); |
1292 | if (IS_ERR(ptr: s)) |
1293 | return ERR_CAST(ptr: s); |
1294 | |
1295 | if (!s->s_root) { |
1296 | err = setup_bdev_super(sb: s, sb_flags: flags, NULL); |
1297 | if (!err) |
1298 | err = nilfs_fill_super(sb: s, data, |
1299 | silent: flags & SB_SILENT ? 1 : 0); |
1300 | if (err) |
1301 | goto failed_super; |
1302 | |
1303 | s->s_flags |= SB_ACTIVE; |
1304 | } else if (!sd.cno) { |
1305 | if (nilfs_tree_is_busy(root_dentry: s->s_root)) { |
1306 | if ((flags ^ s->s_flags) & SB_RDONLY) { |
1307 | nilfs_err(s, |
1308 | "the device already has a %s mount." , |
1309 | sb_rdonly(s) ? "read-only" : "read/write" ); |
1310 | err = -EBUSY; |
1311 | goto failed_super; |
1312 | } |
1313 | } else { |
1314 | /* |
1315 | * Try remount to setup mount states if the current |
1316 | * tree is not mounted and only snapshots use this sb. |
1317 | */ |
1318 | err = nilfs_remount(sb: s, flags: &flags, data); |
1319 | if (err) |
1320 | goto failed_super; |
1321 | } |
1322 | } |
1323 | |
1324 | if (sd.cno) { |
1325 | struct dentry *root_dentry; |
1326 | |
1327 | err = nilfs_attach_snapshot(s, cno: sd.cno, root_dentry: &root_dentry); |
1328 | if (err) |
1329 | goto failed_super; |
1330 | return root_dentry; |
1331 | } |
1332 | |
1333 | return dget(dentry: s->s_root); |
1334 | |
1335 | failed_super: |
1336 | deactivate_locked_super(sb: s); |
1337 | return ERR_PTR(error: err); |
1338 | } |
1339 | |
1340 | struct file_system_type nilfs_fs_type = { |
1341 | .owner = THIS_MODULE, |
1342 | .name = "nilfs2" , |
1343 | .mount = nilfs_mount, |
1344 | .kill_sb = kill_block_super, |
1345 | .fs_flags = FS_REQUIRES_DEV, |
1346 | }; |
1347 | MODULE_ALIAS_FS("nilfs2" ); |
1348 | |
1349 | static void nilfs_inode_init_once(void *obj) |
1350 | { |
1351 | struct nilfs_inode_info *ii = obj; |
1352 | |
1353 | INIT_LIST_HEAD(list: &ii->i_dirty); |
1354 | #ifdef CONFIG_NILFS_XATTR |
1355 | init_rwsem(&ii->xattr_sem); |
1356 | #endif |
1357 | inode_init_once(&ii->vfs_inode); |
1358 | } |
1359 | |
1360 | static void nilfs_segbuf_init_once(void *obj) |
1361 | { |
1362 | memset(obj, 0, sizeof(struct nilfs_segment_buffer)); |
1363 | } |
1364 | |
1365 | static void nilfs_destroy_cachep(void) |
1366 | { |
1367 | /* |
1368 | * Make sure all delayed rcu free inodes are flushed before we |
1369 | * destroy cache. |
1370 | */ |
1371 | rcu_barrier(); |
1372 | |
1373 | kmem_cache_destroy(s: nilfs_inode_cachep); |
1374 | kmem_cache_destroy(s: nilfs_transaction_cachep); |
1375 | kmem_cache_destroy(s: nilfs_segbuf_cachep); |
1376 | kmem_cache_destroy(s: nilfs_btree_path_cache); |
1377 | } |
1378 | |
1379 | static int __init nilfs_init_cachep(void) |
1380 | { |
1381 | nilfs_inode_cachep = kmem_cache_create(name: "nilfs2_inode_cache" , |
1382 | size: sizeof(struct nilfs_inode_info), align: 0, |
1383 | SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT, |
1384 | ctor: nilfs_inode_init_once); |
1385 | if (!nilfs_inode_cachep) |
1386 | goto fail; |
1387 | |
1388 | nilfs_transaction_cachep = kmem_cache_create(name: "nilfs2_transaction_cache" , |
1389 | size: sizeof(struct nilfs_transaction_info), align: 0, |
1390 | SLAB_RECLAIM_ACCOUNT, NULL); |
1391 | if (!nilfs_transaction_cachep) |
1392 | goto fail; |
1393 | |
1394 | nilfs_segbuf_cachep = kmem_cache_create(name: "nilfs2_segbuf_cache" , |
1395 | size: sizeof(struct nilfs_segment_buffer), align: 0, |
1396 | SLAB_RECLAIM_ACCOUNT, ctor: nilfs_segbuf_init_once); |
1397 | if (!nilfs_segbuf_cachep) |
1398 | goto fail; |
1399 | |
1400 | nilfs_btree_path_cache = kmem_cache_create(name: "nilfs2_btree_path_cache" , |
1401 | size: sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX, |
1402 | align: 0, flags: 0, NULL); |
1403 | if (!nilfs_btree_path_cache) |
1404 | goto fail; |
1405 | |
1406 | return 0; |
1407 | |
1408 | fail: |
1409 | nilfs_destroy_cachep(); |
1410 | return -ENOMEM; |
1411 | } |
1412 | |
1413 | static int __init init_nilfs_fs(void) |
1414 | { |
1415 | int err; |
1416 | |
1417 | err = nilfs_init_cachep(); |
1418 | if (err) |
1419 | goto fail; |
1420 | |
1421 | err = nilfs_sysfs_init(); |
1422 | if (err) |
1423 | goto free_cachep; |
1424 | |
1425 | err = register_filesystem(&nilfs_fs_type); |
1426 | if (err) |
1427 | goto deinit_sysfs_entry; |
1428 | |
1429 | printk(KERN_INFO "NILFS version 2 loaded\n" ); |
1430 | return 0; |
1431 | |
1432 | deinit_sysfs_entry: |
1433 | nilfs_sysfs_exit(); |
1434 | free_cachep: |
1435 | nilfs_destroy_cachep(); |
1436 | fail: |
1437 | return err; |
1438 | } |
1439 | |
1440 | static void __exit exit_nilfs_fs(void) |
1441 | { |
1442 | nilfs_destroy_cachep(); |
1443 | nilfs_sysfs_exit(); |
1444 | unregister_filesystem(&nilfs_fs_type); |
1445 | } |
1446 | |
1447 | module_init(init_nilfs_fs) |
1448 | module_exit(exit_nilfs_fs) |
1449 | |