?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Merge tag 'block-5.11-2021-01-10' of git://git.kernel.dk/linux-block
[linux/fpc-iii.git] / fs / nilfs2 / super.c
blob4abd928b0bc839db191e75d4dff935bee6ab7e29
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * super.c - 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 "nilfs.h"
39 #include "export.h"
40 #include "mdt.h"
41 #include "alloc.h"
42 #include "btree.h"
43 #include "btnode.h"
44 #include "page.h"
45 #include "cpfile.h"
46 #include "sufile.h" /* nilfs_sufile_resize(), nilfs_sufile_set_alloc_range() */
47 #include "ifile.h"
48 #include "dat.h"
49 #include "segment.h"
50 #include "segbuf.h"
51
52 MODULE_AUTHOR("NTT Corp.");
53 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
54 "(NILFS)");
55 MODULE_LICENSE("GPL");
56
57 static struct kmem_cache *nilfs_inode_cachep;
58 struct kmem_cache *nilfs_transaction_cachep;
59 struct kmem_cache *nilfs_segbuf_cachep;
60 struct kmem_cache *nilfs_btree_path_cache;
61
62 static int nilfs_setup_super(struct super_block *sb, int is_mount);
63 static int nilfs_remount(struct super_block *sb, int *flags, char *data);
64
65 void __nilfs_msg(struct super_block *sb, const char *fmt, ...)
66 {
67 struct va_format vaf;
68 va_list args;
69 int level;
70
71 va_start(args, fmt);
72
73 level = printk_get_level(fmt);
74 vaf.fmt = printk_skip_level(fmt);
75 vaf.va = &args;
76
77 if (sb)
78 printk("%c%cNILFS (%s): %pV\n",
79 KERN_SOH_ASCII, level, sb->s_id, &vaf);
80 else
81 printk("%c%cNILFS: %pV\n",
82 KERN_SOH_ASCII, level, &vaf);
83
84 va_end(args);
85 }
86
87 static void nilfs_set_error(struct super_block *sb)
88 {
89 struct the_nilfs *nilfs = sb->s_fs_info;
90 struct nilfs_super_block **sbp;
91
92 down_write(&nilfs->ns_sem);
93 if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
94 nilfs->ns_mount_state |= NILFS_ERROR_FS;
95 sbp = nilfs_prepare_super(sb, 0);
96 if (likely(sbp)) {
97 sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
98 if (sbp[1])
99 sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
100 nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
101 }
102 }
103 up_write(&nilfs->ns_sem);
104 }
105
106 /**
107 * __nilfs_error() - report failure condition on a filesystem
108 *
109 * __nilfs_error() sets an ERROR_FS flag on the superblock as well as
110 * reporting an error message. This function should be called when
111 * NILFS detects incoherences or defects of meta data on disk.
112 *
113 * This implements the body of nilfs_error() macro. Normally,
114 * nilfs_error() should be used. As for sustainable errors such as a
115 * single-shot I/O error, nilfs_err() should be used instead.
116 *
117 * Callers should not add a trailing newline since this will do it.
118 */
119 void __nilfs_error(struct super_block *sb, const char *function,
120 const char *fmt, ...)
121 {
122 struct the_nilfs *nilfs = sb->s_fs_info;
123 struct va_format vaf;
124 va_list args;
125
126 va_start(args, fmt);
127
128 vaf.fmt = fmt;
129 vaf.va = &args;
130
131 printk(KERN_CRIT "NILFS error (device %s): %s: %pV\n",
132 sb->s_id, function, &vaf);
133
134 va_end(args);
135
136 if (!sb_rdonly(sb)) {
137 nilfs_set_error(sb);
138
139 if (nilfs_test_opt(nilfs, ERRORS_RO)) {
140 printk(KERN_CRIT "Remounting filesystem read-only\n");
141 sb->s_flags |= SB_RDONLY;
142 }
143 }
144
145 if (nilfs_test_opt(nilfs, ERRORS_PANIC))
146 panic("NILFS (device %s): panic forced after error\n",
147 sb->s_id);
148 }
149
150 struct inode *nilfs_alloc_inode(struct super_block *sb)
151 {
152 struct nilfs_inode_info *ii;
153
154 ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS);
155 if (!ii)
156 return NULL;
157 ii->i_bh = NULL;
158 ii->i_state = 0;
159 ii->i_cno = 0;
160 nilfs_mapping_init(&ii->i_btnode_cache, &ii->vfs_inode);
161 return &ii->vfs_inode;
162 }
163
164 static void nilfs_free_inode(struct inode *inode)
165 {
166 if (nilfs_is_metadata_file_inode(inode))
167 nilfs_mdt_destroy(inode);
168
169 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
170 }
171
172 static int nilfs_sync_super(struct super_block *sb, int flag)
173 {
174 struct the_nilfs *nilfs = sb->s_fs_info;
175 int err;
176
177 retry:
178 set_buffer_dirty(nilfs->ns_sbh[0]);
179 if (nilfs_test_opt(nilfs, BARRIER)) {
180 err = __sync_dirty_buffer(nilfs->ns_sbh[0],
181 REQ_SYNC | REQ_PREFLUSH | REQ_FUA);
182 } else {
183 err = sync_dirty_buffer(nilfs->ns_sbh[0]);
184 }
185
186 if (unlikely(err)) {
187 nilfs_err(sb, "unable to write superblock: err=%d", err);
188 if (err == -EIO && nilfs->ns_sbh[1]) {
189 /*
190 * sbp[0] points to newer log than sbp[1],
191 * so copy sbp[0] to sbp[1] to take over sbp[0].
192 */
193 memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0],
194 nilfs->ns_sbsize);
195 nilfs_fall_back_super_block(nilfs);
196 goto retry;
197 }
198 } else {
199 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
200
201 nilfs->ns_sbwcount++;
202
203 /*
204 * The latest segment becomes trailable from the position
205 * written in superblock.
206 */
207 clear_nilfs_discontinued(nilfs);
208
209 /* update GC protection for recent segments */
210 if (nilfs->ns_sbh[1]) {
211 if (flag == NILFS_SB_COMMIT_ALL) {
212 set_buffer_dirty(nilfs->ns_sbh[1]);
213 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0)
214 goto out;
215 }
216 if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) <
217 le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno))
218 sbp = nilfs->ns_sbp[1];
219 }
220
221 spin_lock(&nilfs->ns_last_segment_lock);
222 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
223 spin_unlock(&nilfs->ns_last_segment_lock);
224 }
225 out:
226 return err;
227 }
228
229 void nilfs_set_log_cursor(struct nilfs_super_block *sbp,
230 struct the_nilfs *nilfs)
231 {
232 sector_t nfreeblocks;
233
234 /* nilfs->ns_sem must be locked by the caller. */
235 nilfs_count_free_blocks(nilfs, &nfreeblocks);
236 sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks);
237
238 spin_lock(&nilfs->ns_last_segment_lock);
239 sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
240 sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
241 sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
242 spin_unlock(&nilfs->ns_last_segment_lock);
243 }
244
245 struct nilfs_super_block **nilfs_prepare_super(struct super_block *sb,
246 int flip)
247 {
248 struct the_nilfs *nilfs = sb->s_fs_info;
249 struct nilfs_super_block **sbp = nilfs->ns_sbp;
250
251 /* nilfs->ns_sem must be locked by the caller. */
252 if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
253 if (sbp[1] &&
254 sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) {
255 memcpy(sbp[0], sbp[1], nilfs->ns_sbsize);
256 } else {
257 nilfs_crit(sb, "superblock broke");
258 return NULL;
259 }
260 } else if (sbp[1] &&
261 sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
262 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
263 }
264
265 if (flip && sbp[1])
266 nilfs_swap_super_block(nilfs);
267
268 return sbp;
269 }
270
271 int nilfs_commit_super(struct super_block *sb, int flag)
272 {
273 struct the_nilfs *nilfs = sb->s_fs_info;
274 struct nilfs_super_block **sbp = nilfs->ns_sbp;
275 time64_t t;
276
277 /* nilfs->ns_sem must be locked by the caller. */
278 t = ktime_get_real_seconds();
279 nilfs->ns_sbwtime = t;
280 sbp[0]->s_wtime = cpu_to_le64(t);
281 sbp[0]->s_sum = 0;
282 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
283 (unsigned char *)sbp[0],
284 nilfs->ns_sbsize));
285 if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) {
286 sbp[1]->s_wtime = sbp[0]->s_wtime;
287 sbp[1]->s_sum = 0;
288 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
289 (unsigned char *)sbp[1],
290 nilfs->ns_sbsize));
291 }
292 clear_nilfs_sb_dirty(nilfs);
293 nilfs->ns_flushed_device = 1;
294 /* make sure store to ns_flushed_device cannot be reordered */
295 smp_wmb();
296 return nilfs_sync_super(sb, flag);
297 }
298
299 /**
300 * nilfs_cleanup_super() - write filesystem state for cleanup
301 * @sb: super block instance to be unmounted or degraded to read-only
302 *
303 * This function restores state flags in the on-disk super block.
304 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
305 * filesystem was not clean previously.
306 */
307 int nilfs_cleanup_super(struct super_block *sb)
308 {
309 struct the_nilfs *nilfs = sb->s_fs_info;
310 struct nilfs_super_block **sbp;
311 int flag = NILFS_SB_COMMIT;
312 int ret = -EIO;
313
314 sbp = nilfs_prepare_super(sb, 0);
315 if (sbp) {
316 sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state);
317 nilfs_set_log_cursor(sbp[0], nilfs);
318 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) {
319 /*
320 * make the "clean" flag also to the opposite
321 * super block if both super blocks point to
322 * the same checkpoint.
323 */
324 sbp[1]->s_state = sbp[0]->s_state;
325 flag = NILFS_SB_COMMIT_ALL;
326 }
327 ret = nilfs_commit_super(sb, flag);
328 }
329 return ret;
330 }
331
332 /**
333 * nilfs_move_2nd_super - relocate secondary super block
334 * @sb: super block instance
335 * @sb2off: new offset of the secondary super block (in bytes)
336 */
337 static int nilfs_move_2nd_super(struct super_block *sb, loff_t sb2off)
338 {
339 struct the_nilfs *nilfs = sb->s_fs_info;
340 struct buffer_head *nsbh;
341 struct nilfs_super_block *nsbp;
342 sector_t blocknr, newblocknr;
343 unsigned long offset;
344 int sb2i; /* array index of the secondary superblock */
345 int ret = 0;
346
347 /* nilfs->ns_sem must be locked by the caller. */
348 if (nilfs->ns_sbh[1] &&
349 nilfs->ns_sbh[1]->b_blocknr > nilfs->ns_first_data_block) {
350 sb2i = 1;
351 blocknr = nilfs->ns_sbh[1]->b_blocknr;
352 } else if (nilfs->ns_sbh[0]->b_blocknr > nilfs->ns_first_data_block) {
353 sb2i = 0;
354 blocknr = nilfs->ns_sbh[0]->b_blocknr;
355 } else {
356 sb2i = -1;
357 blocknr = 0;
358 }
359 if (sb2i >= 0 && (u64)blocknr << nilfs->ns_blocksize_bits == sb2off)
360 goto out; /* super block location is unchanged */
361
362 /* Get new super block buffer */
363 newblocknr = sb2off >> nilfs->ns_blocksize_bits;
364 offset = sb2off & (nilfs->ns_blocksize - 1);
365 nsbh = sb_getblk(sb, newblocknr);
366 if (!nsbh) {
367 nilfs_warn(sb,
368 "unable to move secondary superblock to block %llu",
369 (unsigned long long)newblocknr);
370 ret = -EIO;
371 goto out;
372 }
373 nsbp = (void *)nsbh->b_data + offset;
374 memset(nsbp, 0, nilfs->ns_blocksize);
375
376 if (sb2i >= 0) {
377 memcpy(nsbp, nilfs->ns_sbp[sb2i], nilfs->ns_sbsize);
378 brelse(nilfs->ns_sbh[sb2i]);
379 nilfs->ns_sbh[sb2i] = nsbh;
380 nilfs->ns_sbp[sb2i] = nsbp;
381 } else if (nilfs->ns_sbh[0]->b_blocknr < nilfs->ns_first_data_block) {
382 /* secondary super block will be restored to index 1 */
383 nilfs->ns_sbh[1] = nsbh;
384 nilfs->ns_sbp[1] = nsbp;
385 } else {
386 brelse(nsbh);
387 }
388 out:
389 return ret;
390 }
391
392 /**
393 * nilfs_resize_fs - resize the filesystem
394 * @sb: super block instance
395 * @newsize: new size of the filesystem (in bytes)
396 */
397 int nilfs_resize_fs(struct super_block *sb, __u64 newsize)
398 {
399 struct the_nilfs *nilfs = sb->s_fs_info;
400 struct nilfs_super_block **sbp;
401 __u64 devsize, newnsegs;
402 loff_t sb2off;
403 int ret;
404
405 ret = -ERANGE;
406 devsize = i_size_read(sb->s_bdev->bd_inode);
407 if (newsize > devsize)
408 goto out;
409
410 /*
411 * Write lock is required to protect some functions depending
412 * on the number of segments, the number of reserved segments,
413 * and so forth.
414 */
415 down_write(&nilfs->ns_segctor_sem);
416
417 sb2off = NILFS_SB2_OFFSET_BYTES(newsize);
418 newnsegs = sb2off >> nilfs->ns_blocksize_bits;
419 do_div(newnsegs, nilfs->ns_blocks_per_segment);
420
421 ret = nilfs_sufile_resize(nilfs->ns_sufile, newnsegs);
422 up_write(&nilfs->ns_segctor_sem);
423 if (ret < 0)
424 goto out;
425
426 ret = nilfs_construct_segment(sb);
427 if (ret < 0)
428 goto out;
429
430 down_write(&nilfs->ns_sem);
431 nilfs_move_2nd_super(sb, sb2off);
432 ret = -EIO;
433 sbp = nilfs_prepare_super(sb, 0);
434 if (likely(sbp)) {
435 nilfs_set_log_cursor(sbp[0], nilfs);
436 /*
437 * Drop NILFS_RESIZE_FS flag for compatibility with
438 * mount-time resize which may be implemented in a
439 * future release.
440 */
441 sbp[0]->s_state = cpu_to_le16(le16_to_cpu(sbp[0]->s_state) &
442 ~NILFS_RESIZE_FS);
443 sbp[0]->s_dev_size = cpu_to_le64(newsize);
444 sbp[0]->s_nsegments = cpu_to_le64(nilfs->ns_nsegments);
445 if (sbp[1])
446 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
447 ret = nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
448 }
449 up_write(&nilfs->ns_sem);
450
451 /*
452 * Reset the range of allocatable segments last. This order
453 * is important in the case of expansion because the secondary
454 * superblock must be protected from log write until migration
455 * completes.
456 */
457 if (!ret)
458 nilfs_sufile_set_alloc_range(nilfs->ns_sufile, 0, newnsegs - 1);
459 out:
460 return ret;
461 }
462
463 static void nilfs_put_super(struct super_block *sb)
464 {
465 struct the_nilfs *nilfs = sb->s_fs_info;
466
467 nilfs_detach_log_writer(sb);
468
469 if (!sb_rdonly(sb)) {
470 down_write(&nilfs->ns_sem);
471 nilfs_cleanup_super(sb);
472 up_write(&nilfs->ns_sem);
473 }
474
475 iput(nilfs->ns_sufile);
476 iput(nilfs->ns_cpfile);
477 iput(nilfs->ns_dat);
478
479 destroy_nilfs(nilfs);
480 sb->s_fs_info = NULL;
481 }
482
483 static int nilfs_sync_fs(struct super_block *sb, int wait)
484 {
485 struct the_nilfs *nilfs = sb->s_fs_info;
486 struct nilfs_super_block **sbp;
487 int err = 0;
488
489 /* This function is called when super block should be written back */
490 if (wait)
491 err = nilfs_construct_segment(sb);
492
493 down_write(&nilfs->ns_sem);
494 if (nilfs_sb_dirty(nilfs)) {
495 sbp = nilfs_prepare_super(sb, nilfs_sb_will_flip(nilfs));
496 if (likely(sbp)) {
497 nilfs_set_log_cursor(sbp[0], nilfs);
498 nilfs_commit_super(sb, NILFS_SB_COMMIT);
499 }
500 }
501 up_write(&nilfs->ns_sem);
502
503 if (!err)
504 err = nilfs_flush_device(nilfs);
505
506 return err;
507 }
508
509 int nilfs_attach_checkpoint(struct super_block *sb, __u64 cno, int curr_mnt,
510 struct nilfs_root **rootp)
511 {
512 struct the_nilfs *nilfs = sb->s_fs_info;
513 struct nilfs_root *root;
514 struct nilfs_checkpoint *raw_cp;
515 struct buffer_head *bh_cp;
516 int err = -ENOMEM;
517
518 root = nilfs_find_or_create_root(
519 nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno);
520 if (!root)
521 return err;
522
523 if (root->ifile)
524 goto reuse; /* already attached checkpoint */
525
526 down_read(&nilfs->ns_segctor_sem);
527 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
528 &bh_cp);
529 up_read(&nilfs->ns_segctor_sem);
530 if (unlikely(err)) {
531 if (err == -ENOENT || err == -EINVAL) {
532 nilfs_err(sb,
533 "Invalid checkpoint (checkpoint number=%llu)",
534 (unsigned long long)cno);
535 err = -EINVAL;
536 }
537 goto failed;
538 }
539
540 err = nilfs_ifile_read(sb, root, nilfs->ns_inode_size,
541 &raw_cp->cp_ifile_inode, &root->ifile);
542 if (err)
543 goto failed_bh;
544
545 atomic64_set(&root->inodes_count,
546 le64_to_cpu(raw_cp->cp_inodes_count));
547 atomic64_set(&root->blocks_count,
548 le64_to_cpu(raw_cp->cp_blocks_count));
549
550 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
551
552 reuse:
553 *rootp = root;
554 return 0;
555
556 failed_bh:
557 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
558 failed:
559 nilfs_put_root(root);
560
561 return err;
562 }
563
564 static int nilfs_freeze(struct super_block *sb)
565 {
566 struct the_nilfs *nilfs = sb->s_fs_info;
567 int err;
568
569 if (sb_rdonly(sb))
570 return 0;
571
572 /* Mark super block clean */
573 down_write(&nilfs->ns_sem);
574 err = nilfs_cleanup_super(sb);
575 up_write(&nilfs->ns_sem);
576 return err;
577 }
578
579 static int nilfs_unfreeze(struct super_block *sb)
580 {
581 struct the_nilfs *nilfs = sb->s_fs_info;
582
583 if (sb_rdonly(sb))
584 return 0;
585
586 down_write(&nilfs->ns_sem);
587 nilfs_setup_super(sb, false);
588 up_write(&nilfs->ns_sem);
589 return 0;
590 }
591
592 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
593 {
594 struct super_block *sb = dentry->d_sb;
595 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root;
596 struct the_nilfs *nilfs = root->nilfs;
597 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
598 unsigned long long blocks;
599 unsigned long overhead;
600 unsigned long nrsvblocks;
601 sector_t nfreeblocks;
602 u64 nmaxinodes, nfreeinodes;
603 int err;
604
605 /*
606 * Compute all of the segment blocks
607 *
608 * The blocks before first segment and after last segment
609 * are excluded.
610 */
611 blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments
612 - nilfs->ns_first_data_block;
613 nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment;
614
615 /*
616 * Compute the overhead
617 *
618 * When distributing meta data blocks outside segment structure,
619 * We must count them as the overhead.
620 */
621 overhead = 0;
622
623 err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
624 if (unlikely(err))
625 return err;
626
627 err = nilfs_ifile_count_free_inodes(root->ifile,
628 &nmaxinodes, &nfreeinodes);
629 if (unlikely(err)) {
630 nilfs_warn(sb, "failed to count free inodes: err=%d", err);
631 if (err == -ERANGE) {
632 /*
633 * If nilfs_palloc_count_max_entries() returns
634 * -ERANGE error code then we simply treat
635 * curent inodes count as maximum possible and
636 * zero as free inodes value.
637 */
638 nmaxinodes = atomic64_read(&root->inodes_count);
639 nfreeinodes = 0;
640 err = 0;
641 } else
642 return err;
643 }
644
645 buf->f_type = NILFS_SUPER_MAGIC;
646 buf->f_bsize = sb->s_blocksize;
647 buf->f_blocks = blocks - overhead;
648 buf->f_bfree = nfreeblocks;
649 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
650 (buf->f_bfree - nrsvblocks) : 0;
651 buf->f_files = nmaxinodes;
652 buf->f_ffree = nfreeinodes;
653 buf->f_namelen = NILFS_NAME_LEN;
654 buf->f_fsid = u64_to_fsid(id);
655
656 return 0;
657 }
658
659 static int nilfs_show_options(struct seq_file *seq, struct dentry *dentry)
660 {
661 struct super_block *sb = dentry->d_sb;
662 struct the_nilfs *nilfs = sb->s_fs_info;
663 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root;
664
665 if (!nilfs_test_opt(nilfs, BARRIER))
666 seq_puts(seq, ",nobarrier");
667 if (root->cno != NILFS_CPTREE_CURRENT_CNO)
668 seq_printf(seq, ",cp=%llu", (unsigned long long)root->cno);
669 if (nilfs_test_opt(nilfs, ERRORS_PANIC))
670 seq_puts(seq, ",errors=panic");
671 if (nilfs_test_opt(nilfs, ERRORS_CONT))
672 seq_puts(seq, ",errors=continue");
673 if (nilfs_test_opt(nilfs, STRICT_ORDER))
674 seq_puts(seq, ",order=strict");
675 if (nilfs_test_opt(nilfs, NORECOVERY))
676 seq_puts(seq, ",norecovery");
677 if (nilfs_test_opt(nilfs, DISCARD))
678 seq_puts(seq, ",discard");
679
680 return 0;
681 }
682
683 static const struct super_operations nilfs_sops = {
684 .alloc_inode = nilfs_alloc_inode,
685 .free_inode = nilfs_free_inode,
686 .dirty_inode = nilfs_dirty_inode,
687 .evict_inode = nilfs_evict_inode,
688 .put_super = nilfs_put_super,
689 .sync_fs = nilfs_sync_fs,
690 .freeze_fs = nilfs_freeze,
691 .unfreeze_fs = nilfs_unfreeze,
692 .statfs = nilfs_statfs,
693 .remount_fs = nilfs_remount,
694 .show_options = nilfs_show_options
695 };
696
697 enum {
698 Opt_err_cont, Opt_err_panic, Opt_err_ro,
699 Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,
700 Opt_discard, Opt_nodiscard, Opt_err,
701 };
702
703 static match_table_t tokens = {
704 {Opt_err_cont, "errors=continue"},
705 {Opt_err_panic, "errors=panic"},
706 {Opt_err_ro, "errors=remount-ro"},
707 {Opt_barrier, "barrier"},
708 {Opt_nobarrier, "nobarrier"},
709 {Opt_snapshot, "cp=%u"},
710 {Opt_order, "order=%s"},
711 {Opt_norecovery, "norecovery"},
712 {Opt_discard, "discard"},
713 {Opt_nodiscard, "nodiscard"},
714 {Opt_err, NULL}
715 };
716
717 static int parse_options(char *options, struct super_block *sb, int is_remount)
718 {
719 struct the_nilfs *nilfs = sb->s_fs_info;
720 char *p;
721 substring_t args[MAX_OPT_ARGS];
722
723 if (!options)
724 return 1;
725
726 while ((p = strsep(&options, ",")) != NULL) {
727 int token;
728
729 if (!*p)
730 continue;
731
732 token = match_token(p, tokens, args);
733 switch (token) {
734 case Opt_barrier:
735 nilfs_set_opt(nilfs, BARRIER);
736 break;
737 case Opt_nobarrier:
738 nilfs_clear_opt(nilfs, BARRIER);
739 break;
740 case Opt_order:
741 if (strcmp(args[0].from, "relaxed") == 0)
742 /* Ordered data semantics */
743 nilfs_clear_opt(nilfs, STRICT_ORDER);
744 else if (strcmp(args[0].from, "strict") == 0)
745 /* Strict in-order semantics */
746 nilfs_set_opt(nilfs, STRICT_ORDER);
747 else
748 return 0;
749 break;
750 case Opt_err_panic:
751 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_PANIC);
752 break;
753 case Opt_err_ro:
754 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_RO);
755 break;
756 case Opt_err_cont:
757 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_CONT);
758 break;
759 case Opt_snapshot:
760 if (is_remount) {
761 nilfs_err(sb,
762 "\"%s\" option is invalid for remount",
763 p);
764 return 0;
765 }
766 break;
767 case Opt_norecovery:
768 nilfs_set_opt(nilfs, NORECOVERY);
769 break;
770 case Opt_discard:
771 nilfs_set_opt(nilfs, DISCARD);
772 break;
773 case Opt_nodiscard:
774 nilfs_clear_opt(nilfs, DISCARD);
775 break;
776 default:
777 nilfs_err(sb, "unrecognized mount option \"%s\"", p);
778 return 0;
779 }
780 }
781 return 1;
782 }
783
784 static inline void
785 nilfs_set_default_options(struct super_block *sb,
786 struct nilfs_super_block *sbp)
787 {
788 struct the_nilfs *nilfs = sb->s_fs_info;
789
790 nilfs->ns_mount_opt =
791 NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER;
792 }
793
794 static int nilfs_setup_super(struct super_block *sb, int is_mount)
795 {
796 struct the_nilfs *nilfs = sb->s_fs_info;
797 struct nilfs_super_block **sbp;
798 int max_mnt_count;
799 int mnt_count;
800
801 /* nilfs->ns_sem must be locked by the caller. */
802 sbp = nilfs_prepare_super(sb, 0);
803 if (!sbp)
804 return -EIO;
805
806 if (!is_mount)
807 goto skip_mount_setup;
808
809 max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count);
810 mnt_count = le16_to_cpu(sbp[0]->s_mnt_count);
811
812 if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
813 nilfs_warn(sb, "mounting fs with errors");
814 #if 0
815 } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
816 nilfs_warn(sb, "maximal mount count reached");
817 #endif
818 }
819 if (!max_mnt_count)
820 sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
821
822 sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1);
823 sbp[0]->s_mtime = cpu_to_le64(ktime_get_real_seconds());
824
825 skip_mount_setup:
826 sbp[0]->s_state =
827 cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
828 /* synchronize sbp[1] with sbp[0] */
829 if (sbp[1])
830 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
831 return nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
832 }
833
834 struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
835 u64 pos, int blocksize,
836 struct buffer_head **pbh)
837 {
838 unsigned long long sb_index = pos;
839 unsigned long offset;
840
841 offset = do_div(sb_index, blocksize);
842 *pbh = sb_bread(sb, sb_index);
843 if (!*pbh)
844 return NULL;
845 return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
846 }
847
848 int nilfs_store_magic_and_option(struct super_block *sb,
849 struct nilfs_super_block *sbp,
850 char *data)
851 {
852 struct the_nilfs *nilfs = sb->s_fs_info;
853
854 sb->s_magic = le16_to_cpu(sbp->s_magic);
855
856 /* FS independent flags */
857 #ifdef NILFS_ATIME_DISABLE
858 sb->s_flags |= SB_NOATIME;
859 #endif
860
861 nilfs_set_default_options(sb, sbp);
862
863 nilfs->ns_resuid = le16_to_cpu(sbp->s_def_resuid);
864 nilfs->ns_resgid = le16_to_cpu(sbp->s_def_resgid);
865 nilfs->ns_interval = le32_to_cpu(sbp->s_c_interval);
866 nilfs->ns_watermark = le32_to_cpu(sbp->s_c_block_max);
867
868 return !parse_options(data, sb, 0) ? -EINVAL : 0;
869 }
870
871 int nilfs_check_feature_compatibility(struct super_block *sb,
872 struct nilfs_super_block *sbp)
873 {
874 __u64 features;
875
876 features = le64_to_cpu(sbp->s_feature_incompat) &
877 ~NILFS_FEATURE_INCOMPAT_SUPP;
878 if (features) {
879 nilfs_err(sb,
880 "couldn't mount because of unsupported optional features (%llx)",
881 (unsigned long long)features);
882 return -EINVAL;
883 }
884 features = le64_to_cpu(sbp->s_feature_compat_ro) &
885 ~NILFS_FEATURE_COMPAT_RO_SUPP;
886 if (!sb_rdonly(sb) && features) {
887 nilfs_err(sb,
888 "couldn't mount RDWR because of unsupported optional features (%llx)",
889 (unsigned long long)features);
890 return -EINVAL;
891 }
892 return 0;
893 }
894
895 static int nilfs_get_root_dentry(struct super_block *sb,
896 struct nilfs_root *root,
897 struct dentry **root_dentry)
898 {
899 struct inode *inode;
900 struct dentry *dentry;
901 int ret = 0;
902
903 inode = nilfs_iget(sb, root, NILFS_ROOT_INO);
904 if (IS_ERR(inode)) {
905 ret = PTR_ERR(inode);
906 nilfs_err(sb, "error %d getting root inode", ret);
907 goto out;
908 }
909 if (!S_ISDIR(inode->i_mode) || !inode->i_blocks || !inode->i_size) {
910 iput(inode);
911 nilfs_err(sb, "corrupt root inode");
912 ret = -EINVAL;
913 goto out;
914 }
915
916 if (root->cno == NILFS_CPTREE_CURRENT_CNO) {
917 dentry = d_find_alias(inode);
918 if (!dentry) {
919 dentry = d_make_root(inode);
920 if (!dentry) {
921 ret = -ENOMEM;
922 goto failed_dentry;
923 }
924 } else {
925 iput(inode);
926 }
927 } else {
928 dentry = d_obtain_root(inode);
929 if (IS_ERR(dentry)) {
930 ret = PTR_ERR(dentry);
931 goto failed_dentry;
932 }
933 }
934 *root_dentry = dentry;
935 out:
936 return ret;
937
938 failed_dentry:
939 nilfs_err(sb, "error %d getting root dentry", ret);
940 goto out;
941 }
942
943 static int nilfs_attach_snapshot(struct super_block *s, __u64 cno,
944 struct dentry **root_dentry)
945 {
946 struct the_nilfs *nilfs = s->s_fs_info;
947 struct nilfs_root *root;
948 int ret;
949
950 mutex_lock(&nilfs->ns_snapshot_mount_mutex);
951
952 down_read(&nilfs->ns_segctor_sem);
953 ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno);
954 up_read(&nilfs->ns_segctor_sem);
955 if (ret < 0) {
956 ret = (ret == -ENOENT) ? -EINVAL : ret;
957 goto out;
958 } else if (!ret) {
959 nilfs_err(s,
960 "The specified checkpoint is not a snapshot (checkpoint number=%llu)",
961 (unsigned long long)cno);
962 ret = -EINVAL;
963 goto out;
964 }
965
966 ret = nilfs_attach_checkpoint(s, cno, false, &root);
967 if (ret) {
968 nilfs_err(s,
969 "error %d while loading snapshot (checkpoint number=%llu)",
970 ret, (unsigned long long)cno);
971 goto out;
972 }
973 ret = nilfs_get_root_dentry(s, root, root_dentry);
974 nilfs_put_root(root);
975 out:
976 mutex_unlock(&nilfs->ns_snapshot_mount_mutex);
977 return ret;
978 }
979
980 /**
981 * nilfs_tree_is_busy() - try to shrink dentries of a checkpoint
982 * @root_dentry: root dentry of the tree to be shrunk
983 *
984 * This function returns true if the tree was in-use.
985 */
986 static bool nilfs_tree_is_busy(struct dentry *root_dentry)
987 {
988 shrink_dcache_parent(root_dentry);
989 return d_count(root_dentry) > 1;
990 }
991
992 int nilfs_checkpoint_is_mounted(struct super_block *sb, __u64 cno)
993 {
994 struct the_nilfs *nilfs = sb->s_fs_info;
995 struct nilfs_root *root;
996 struct inode *inode;
997 struct dentry *dentry;
998 int ret;
999
1000 if (cno > nilfs->ns_cno)
1001 return false;
1002
1003 if (cno >= nilfs_last_cno(nilfs))
1004 return true; /* protect recent checkpoints */
1005
1006 ret = false;
1007 root = nilfs_lookup_root(nilfs, cno);
1008 if (root) {
1009 inode = nilfs_ilookup(sb, root, NILFS_ROOT_INO);
1010 if (inode) {
1011 dentry = d_find_alias(inode);
1012 if (dentry) {
1013 ret = nilfs_tree_is_busy(dentry);
1014 dput(dentry);
1015 }
1016 iput(inode);
1017 }
1018 nilfs_put_root(root);
1019 }
1020 return ret;
1021 }
1022
1023 /**
1024 * nilfs_fill_super() - initialize a super block instance
1025 * @sb: super_block
1026 * @data: mount options
1027 * @silent: silent mode flag
1028 *
1029 * This function is called exclusively by nilfs->ns_mount_mutex.
1030 * So, the recovery process is protected from other simultaneous mounts.
1031 */
1032 static int
1033 nilfs_fill_super(struct super_block *sb, void *data, int silent)
1034 {
1035 struct the_nilfs *nilfs;
1036 struct nilfs_root *fsroot;
1037 __u64 cno;
1038 int err;
1039
1040 nilfs = alloc_nilfs(sb);
1041 if (!nilfs)
1042 return -ENOMEM;
1043
1044 sb->s_fs_info = nilfs;
1045
1046 err = init_nilfs(nilfs, sb, (char *)data);
1047 if (err)
1048 goto failed_nilfs;
1049
1050 sb->s_op = &nilfs_sops;
1051 sb->s_export_op = &nilfs_export_ops;
1052 sb->s_root = NULL;
1053 sb->s_time_gran = 1;
1054 sb->s_max_links = NILFS_LINK_MAX;
1055
1056 sb->s_bdi = bdi_get(sb->s_bdev->bd_bdi);
1057
1058 err = load_nilfs(nilfs, sb);
1059 if (err)
1060 goto failed_nilfs;
1061
1062 cno = nilfs_last_cno(nilfs);
1063 err = nilfs_attach_checkpoint(sb, cno, true, &fsroot);
1064 if (err) {
1065 nilfs_err(sb,
1066 "error %d while loading last checkpoint (checkpoint number=%llu)",
1067 err, (unsigned long long)cno);
1068 goto failed_unload;
1069 }
1070
1071 if (!sb_rdonly(sb)) {
1072 err = nilfs_attach_log_writer(sb, fsroot);
1073 if (err)
1074 goto failed_checkpoint;
1075 }
1076
1077 err = nilfs_get_root_dentry(sb, fsroot, &sb->s_root);
1078 if (err)
1079 goto failed_segctor;
1080
1081 nilfs_put_root(fsroot);
1082
1083 if (!sb_rdonly(sb)) {
1084 down_write(&nilfs->ns_sem);
1085 nilfs_setup_super(sb, true);
1086 up_write(&nilfs->ns_sem);
1087 }
1088
1089 return 0;
1090
1091 failed_segctor:
1092 nilfs_detach_log_writer(sb);
1093
1094 failed_checkpoint:
1095 nilfs_put_root(fsroot);
1096
1097 failed_unload:
1098 iput(nilfs->ns_sufile);
1099 iput(nilfs->ns_cpfile);
1100 iput(nilfs->ns_dat);
1101
1102 failed_nilfs:
1103 destroy_nilfs(nilfs);
1104 return err;
1105 }
1106
1107 static int nilfs_remount(struct super_block *sb, int *flags, char *data)
1108 {
1109 struct the_nilfs *nilfs = sb->s_fs_info;
1110 unsigned long old_sb_flags;
1111 unsigned long old_mount_opt;
1112 int err;
1113
1114 sync_filesystem(sb);
1115 old_sb_flags = sb->s_flags;
1116 old_mount_opt = nilfs->ns_mount_opt;
1117
1118 if (!parse_options(data, sb, 1)) {
1119 err = -EINVAL;
1120 goto restore_opts;
1121 }
1122 sb->s_flags = (sb->s_flags & ~SB_POSIXACL);
1123
1124 err = -EINVAL;
1125
1126 if (!nilfs_valid_fs(nilfs)) {
1127 nilfs_warn(sb,
1128 "couldn't remount because the filesystem is in an incomplete recovery state");
1129 goto restore_opts;
1130 }
1131
1132 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
1133 goto out;
1134 if (*flags & SB_RDONLY) {
1135 /* Shutting down log writer */
1136 nilfs_detach_log_writer(sb);
1137 sb->s_flags |= SB_RDONLY;
1138
1139 /*
1140 * Remounting a valid RW partition RDONLY, so set
1141 * the RDONLY flag and then mark the partition as valid again.
1142 */
1143 down_write(&nilfs->ns_sem);
1144 nilfs_cleanup_super(sb);
1145 up_write(&nilfs->ns_sem);
1146 } else {
1147 __u64 features;
1148 struct nilfs_root *root;
1149
1150 /*
1151 * Mounting a RDONLY partition read-write, so reread and
1152 * store the current valid flag. (It may have been changed
1153 * by fsck since we originally mounted the partition.)
1154 */
1155 down_read(&nilfs->ns_sem);
1156 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) &
1157 ~NILFS_FEATURE_COMPAT_RO_SUPP;
1158 up_read(&nilfs->ns_sem);
1159 if (features) {
1160 nilfs_warn(sb,
1161 "couldn't remount RDWR because of unsupported optional features (%llx)",
1162 (unsigned long long)features);
1163 err = -EROFS;
1164 goto restore_opts;
1165 }
1166
1167 sb->s_flags &= ~SB_RDONLY;
1168
1169 root = NILFS_I(d_inode(sb->s_root))->i_root;
1170 err = nilfs_attach_log_writer(sb, root);
1171 if (err)
1172 goto restore_opts;
1173
1174 down_write(&nilfs->ns_sem);
1175 nilfs_setup_super(sb, true);
1176 up_write(&nilfs->ns_sem);
1177 }
1178 out:
1179 return 0;
1180
1181 restore_opts:
1182 sb->s_flags = old_sb_flags;
1183 nilfs->ns_mount_opt = old_mount_opt;
1184 return err;
1185 }
1186
1187 struct nilfs_super_data {
1188 struct block_device *bdev;
1189 __u64 cno;
1190 int flags;
1191 };
1192
1193 static int nilfs_parse_snapshot_option(const char *option,
1194 const substring_t *arg,
1195 struct nilfs_super_data *sd)
1196 {
1197 unsigned long long val;
1198 const char *msg = NULL;
1199 int err;
1200
1201 if (!(sd->flags & SB_RDONLY)) {
1202 msg = "read-only option is not specified";
1203 goto parse_error;
1204 }
1205
1206 err = kstrtoull(arg->from, 0, &val);
1207 if (err) {
1208 if (err == -ERANGE)
1209 msg = "too large checkpoint number";
1210 else
1211 msg = "malformed argument";
1212 goto parse_error;
1213 } else if (val == 0) {
1214 msg = "invalid checkpoint number 0";
1215 goto parse_error;
1216 }
1217 sd->cno = val;
1218 return 0;
1219
1220 parse_error:
1221 nilfs_err(NULL, "invalid option \"%s\": %s", option, msg);
1222 return 1;
1223 }
1224
1225 /**
1226 * nilfs_identify - pre-read mount options needed to identify mount instance
1227 * @data: mount options
1228 * @sd: nilfs_super_data
1229 */
1230 static int nilfs_identify(char *data, struct nilfs_super_data *sd)
1231 {
1232 char *p, *options = data;
1233 substring_t args[MAX_OPT_ARGS];
1234 int token;
1235 int ret = 0;
1236
1237 do {
1238 p = strsep(&options, ",");
1239 if (p != NULL && *p) {
1240 token = match_token(p, tokens, args);
1241 if (token == Opt_snapshot)
1242 ret = nilfs_parse_snapshot_option(p, &args[0],
1243 sd);
1244 }
1245 if (!options)
1246 break;
1247 BUG_ON(options == data);
1248 *(options - 1) = ',';
1249 } while (!ret);
1250 return ret;
1251 }
1252
1253 static int nilfs_set_bdev_super(struct super_block *s, void *data)
1254 {
1255 s->s_bdev = data;
1256 s->s_dev = s->s_bdev->bd_dev;
1257 return 0;
1258 }
1259
1260 static int nilfs_test_bdev_super(struct super_block *s, void *data)
1261 {
1262 return (void *)s->s_bdev == data;
1263 }
1264
1265 static struct dentry *
1266 nilfs_mount(struct file_system_type *fs_type, int flags,
1267 const char *dev_name, void *data)
1268 {
1269 struct nilfs_super_data sd;
1270 struct super_block *s;
1271 fmode_t mode = FMODE_READ | FMODE_EXCL;
1272 struct dentry *root_dentry;
1273 int err, s_new = false;
1274
1275 if (!(flags & SB_RDONLY))
1276 mode |= FMODE_WRITE;
1277
1278 sd.bdev = blkdev_get_by_path(dev_name, mode, fs_type);
1279 if (IS_ERR(sd.bdev))
1280 return ERR_CAST(sd.bdev);
1281
1282 sd.cno = 0;
1283 sd.flags = flags;
1284 if (nilfs_identify((char *)data, &sd)) {
1285 err = -EINVAL;
1286 goto failed;
1287 }
1288
1289 /*
1290 * once the super is inserted into the list by sget, s_umount
1291 * will protect the lockfs code from trying to start a snapshot
1292 * while we are mounting
1293 */
1294 mutex_lock(&sd.bdev->bd_fsfreeze_mutex);
1295 if (sd.bdev->bd_fsfreeze_count > 0) {
1296 mutex_unlock(&sd.bdev->bd_fsfreeze_mutex);
1297 err = -EBUSY;
1298 goto failed;
1299 }
1300 s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, flags,
1301 sd.bdev);
1302 mutex_unlock(&sd.bdev->bd_fsfreeze_mutex);
1303 if (IS_ERR(s)) {
1304 err = PTR_ERR(s);
1305 goto failed;
1306 }
1307
1308 if (!s->s_root) {
1309 s_new = true;
1310
1311 /* New superblock instance created */
1312 s->s_mode = mode;
1313 snprintf(s->s_id, sizeof(s->s_id), "%pg", sd.bdev);
1314 sb_set_blocksize(s, block_size(sd.bdev));
1315
1316 err = nilfs_fill_super(s, data, flags & SB_SILENT ? 1 : 0);
1317 if (err)
1318 goto failed_super;
1319
1320 s->s_flags |= SB_ACTIVE;
1321 } else if (!sd.cno) {
1322 if (nilfs_tree_is_busy(s->s_root)) {
1323 if ((flags ^ s->s_flags) & SB_RDONLY) {
1324 nilfs_err(s,
1325 "the device already has a %s mount.",
1326 sb_rdonly(s) ? "read-only" : "read/write");
1327 err = -EBUSY;
1328 goto failed_super;
1329 }
1330 } else {
1331 /*
1332 * Try remount to setup mount states if the current
1333 * tree is not mounted and only snapshots use this sb.
1334 */
1335 err = nilfs_remount(s, &flags, data);
1336 if (err)
1337 goto failed_super;
1338 }
1339 }
1340
1341 if (sd.cno) {
1342 err = nilfs_attach_snapshot(s, sd.cno, &root_dentry);
1343 if (err)
1344 goto failed_super;
1345 } else {
1346 root_dentry = dget(s->s_root);
1347 }
1348
1349 if (!s_new)
1350 blkdev_put(sd.bdev, mode);
1351
1352 return root_dentry;
1353
1354 failed_super:
1355 deactivate_locked_super(s);
1356
1357 failed:
1358 if (!s_new)
1359 blkdev_put(sd.bdev, mode);
1360 return ERR_PTR(err);
1361 }
1362
1363 struct file_system_type nilfs_fs_type = {
1364 .owner = THIS_MODULE,
1365 .name = "nilfs2",
1366 .mount = nilfs_mount,
1367 .kill_sb = kill_block_super,
1368 .fs_flags = FS_REQUIRES_DEV,
1369 };
1370 MODULE_ALIAS_FS("nilfs2");
1371
1372 static void nilfs_inode_init_once(void *obj)
1373 {
1374 struct nilfs_inode_info *ii = obj;
1375
1376 INIT_LIST_HEAD(&ii->i_dirty);
1377 #ifdef CONFIG_NILFS_XATTR
1378 init_rwsem(&ii->xattr_sem);
1379 #endif
1380 address_space_init_once(&ii->i_btnode_cache);
1381 ii->i_bmap = &ii->i_bmap_data;
1382 inode_init_once(&ii->vfs_inode);
1383 }
1384
1385 static void nilfs_segbuf_init_once(void *obj)
1386 {
1387 memset(obj, 0, sizeof(struct nilfs_segment_buffer));
1388 }
1389
1390 static void nilfs_destroy_cachep(void)
1391 {
1392 /*
1393 * Make sure all delayed rcu free inodes are flushed before we
1394 * destroy cache.
1395 */
1396 rcu_barrier();
1397
1398 kmem_cache_destroy(nilfs_inode_cachep);
1399 kmem_cache_destroy(nilfs_transaction_cachep);
1400 kmem_cache_destroy(nilfs_segbuf_cachep);
1401 kmem_cache_destroy(nilfs_btree_path_cache);
1402 }
1403
1404 static int __init nilfs_init_cachep(void)
1405 {
1406 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
1407 sizeof(struct nilfs_inode_info), 0,
1408 SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT,
1409 nilfs_inode_init_once);
1410 if (!nilfs_inode_cachep)
1411 goto fail;
1412
1413 nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache",
1414 sizeof(struct nilfs_transaction_info), 0,
1415 SLAB_RECLAIM_ACCOUNT, NULL);
1416 if (!nilfs_transaction_cachep)
1417 goto fail;
1418
1419 nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache",
1420 sizeof(struct nilfs_segment_buffer), 0,
1421 SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once);
1422 if (!nilfs_segbuf_cachep)
1423 goto fail;
1424
1425 nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache",
1426 sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX,
1427 0, 0, NULL);
1428 if (!nilfs_btree_path_cache)
1429 goto fail;
1430
1431 return 0;
1432
1433 fail:
1434 nilfs_destroy_cachep();
1435 return -ENOMEM;
1436 }
1437
1438 static int __init init_nilfs_fs(void)
1439 {
1440 int err;
1441
1442 err = nilfs_init_cachep();
1443 if (err)
1444 goto fail;
1445
1446 err = nilfs_sysfs_init();
1447 if (err)
1448 goto free_cachep;
1449
1450 err = register_filesystem(&nilfs_fs_type);
1451 if (err)
1452 goto deinit_sysfs_entry;
1453
1454 printk(KERN_INFO "NILFS version 2 loaded\n");
1455 return 0;
1456
1457 deinit_sysfs_entry:
1458 nilfs_sysfs_exit();
1459 free_cachep:
1460 nilfs_destroy_cachep();
1461 fail:
1462 return err;
1463 }
1464
1465 static void __exit exit_nilfs_fs(void)
1466 {
1467 nilfs_destroy_cachep();
1468 nilfs_sysfs_exit();
1469 unregister_filesystem(&nilfs_fs_type);
1470 }
1471
1472 module_init(init_nilfs_fs)
1473 module_exit(exit_nilfs_fs)
Linux with added FPC-III support