]> bbs.cooldavid.org Git - net-next-2.6.git/blame - fs/nilfs2/the_nilfs.c
git://bbs.cooldavid.org / net-next-2.6.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
Staging: batman-adv: fix function prototype
[net-next-2.6.git] / fs / nilfs2 / the_nilfs.c
CommitLineData
8a9d2191
RK		 1/*
2 * the_nilfs.c - the_nilfs shared structure.
3 *
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
21 *
22 */
23
24#include <linux/buffer_head.h>
25#include <linux/slab.h>
26#include <linux/blkdev.h>
27#include <linux/backing-dev.h>
e339ad31 28#include <linux/crc32.h>
8a9d2191
RK		 29#include "nilfs.h"
30#include "segment.h"
31#include "alloc.h"
32#include "cpfile.h"
33#include "sufile.h"
34#include "dat.h"
8a9d2191
RK		 35#include "segbuf.h"
36
33c8e57c
RK		 37
38static LIST_HEAD(nilfs_objects);
39static DEFINE_SPINLOCK(nilfs_lock);
40
8a9d2191
RK		 41void nilfs_set_last_segment(struct the_nilfs *nilfs,
42 sector_t start_blocknr, u64 seq, __u64 cno)
43{
44 spin_lock(&nilfs->ns_last_segment_lock);
45 nilfs->ns_last_pseg = start_blocknr;
46 nilfs->ns_last_seq = seq;
47 nilfs->ns_last_cno = cno;
48 spin_unlock(&nilfs->ns_last_segment_lock);
49}
50
51/**
52 * alloc_nilfs - allocate the_nilfs structure
53 * @bdev: block device to which the_nilfs is related
54 *
55 * alloc_nilfs() allocates memory for the_nilfs and
56 * initializes its reference count and locks.
57 *
58 * Return Value: On success, pointer to the_nilfs is returned.
59 * On error, NULL is returned.
60 */
33c8e57c 61static struct the_nilfs *alloc_nilfs(struct block_device *bdev)
8a9d2191
RK		 62{
63 struct the_nilfs *nilfs;
64
65 nilfs = kzalloc(sizeof(*nilfs), GFP_KERNEL);
66 if (!nilfs)
67 return NULL;
68
69 nilfs->ns_bdev = bdev;
70 atomic_set(&nilfs->ns_count, 1);
8a9d2191
RK		 71 atomic_set(&nilfs->ns_ndirtyblks, 0);
72 init_rwsem(&nilfs->ns_sem);
e59399d0 73 init_rwsem(&nilfs->ns_super_sem);
aa7dfb89 74 mutex_init(&nilfs->ns_mount_mutex);
027d6404 75 init_rwsem(&nilfs->ns_writer_sem);
33c8e57c 76 INIT_LIST_HEAD(&nilfs->ns_list);
8a9d2191
RK		 77 INIT_LIST_HEAD(&nilfs->ns_supers);
78 spin_lock_init(&nilfs->ns_last_segment_lock);
79 nilfs->ns_gc_inodes_h = NULL;
8a9d2191 80 init_rwsem(&nilfs->ns_segctor_sem);
8a9d2191
RK		 81
82 return nilfs;
83}
84
33c8e57c
RK		 85/**
86 * find_or_create_nilfs - find or create nilfs object
87 * @bdev: block device to which the_nilfs is related
88 *
89 * find_nilfs() looks up an existent nilfs object created on the
90 * device and gets the reference count of the object. If no nilfs object
91 * is found on the device, a new nilfs object is allocated.
92 *
93 * Return Value: On success, pointer to the nilfs object is returned.
94 * On error, NULL is returned.
95 */
96struct the_nilfs *find_or_create_nilfs(struct block_device *bdev)
97{
98 struct the_nilfs *nilfs, *new = NULL;
99
100 retry:
101 spin_lock(&nilfs_lock);
102 list_for_each_entry(nilfs, &nilfs_objects, ns_list) {
103 if (nilfs->ns_bdev == bdev) {
104 get_nilfs(nilfs);
105 spin_unlock(&nilfs_lock);
106 if (new)
107 put_nilfs(new);
108 return nilfs; /* existing object */
109 }
110 }
111 if (new) {
112 list_add_tail(&new->ns_list, &nilfs_objects);
113 spin_unlock(&nilfs_lock);
114 return new; /* new object */
115 }
116 spin_unlock(&nilfs_lock);
117
118 new = alloc_nilfs(bdev);
119 if (new)
120 goto retry;
121 return NULL; /* insufficient memory */
122}
123
8a9d2191
RK		 124/**
125 * put_nilfs - release a reference to the_nilfs
126 * @nilfs: the_nilfs structure to be released
127 *
128 * put_nilfs() decrements a reference counter of the_nilfs.
129 * If the reference count reaches zero, the_nilfs is freed.
130 */
131void put_nilfs(struct the_nilfs *nilfs)
132{
33c8e57c
RK		 133 spin_lock(&nilfs_lock);
134 if (!atomic_dec_and_test(&nilfs->ns_count)) {
135 spin_unlock(&nilfs_lock);
8a9d2191 136 return;
33c8e57c
RK		 137 }
138 list_del_init(&nilfs->ns_list);
139 spin_unlock(&nilfs_lock);
140
8a9d2191 141 /*
33c8e57c 142 * Increment of ns_count never occurs below because the caller
8a9d2191
RK		 143 * of get_nilfs() holds at least one reference to the_nilfs.
144 * Thus its exclusion control is not required here.
145 */
33c8e57c 146
8a9d2191
RK		 147 might_sleep();
148 if (nilfs_loaded(nilfs)) {
8a9d2191 149 nilfs_mdt_destroy(nilfs->ns_sufile);
8a9d2191 150 nilfs_mdt_destroy(nilfs->ns_cpfile);
8a9d2191 151 nilfs_mdt_destroy(nilfs->ns_dat);
8a9d2191
RK		 152 nilfs_mdt_destroy(nilfs->ns_gc_dat);
153 }
154 if (nilfs_init(nilfs)) {
155 nilfs_destroy_gccache(nilfs);
e339ad31
RK		 156 brelse(nilfs->ns_sbh[0]);
157 brelse(nilfs->ns_sbh[1]);
8a9d2191
RK		 158 }
159 kfree(nilfs);
160}
161
162static int nilfs_load_super_root(struct the_nilfs *nilfs,
163 struct nilfs_sb_info *sbi, sector_t sr_block)
164{
165 struct buffer_head *bh_sr;
166 struct nilfs_super_root *raw_sr;
e339ad31 167 struct nilfs_super_block **sbp = nilfs->ns_sbp;
8a9d2191
RK		 168 unsigned dat_entry_size, segment_usage_size, checkpoint_size;
169 unsigned inode_size;
170 int err;
171
172 err = nilfs_read_super_root_block(sbi->s_super, sr_block, &bh_sr, 1);
173 if (unlikely(err))
174 return err;
175
176 down_read(&nilfs->ns_sem);
e339ad31
RK		 177 dat_entry_size = le16_to_cpu(sbp[0]->s_dat_entry_size);
178 checkpoint_size = le16_to_cpu(sbp[0]->s_checkpoint_size);
179 segment_usage_size = le16_to_cpu(sbp[0]->s_segment_usage_size);
8a9d2191
RK		 180 up_read(&nilfs->ns_sem);
181
182 inode_size = nilfs->ns_inode_size;
183
184 err = -ENOMEM;
79739565 185 nilfs->ns_dat = nilfs_dat_new(nilfs, dat_entry_size);
8a9d2191
RK		 186 if (unlikely(!nilfs->ns_dat))
187 goto failed;
188
79739565 189 nilfs->ns_gc_dat = nilfs_dat_new(nilfs, dat_entry_size);
8a9d2191
RK		 190 if (unlikely(!nilfs->ns_gc_dat))
191 goto failed_dat;
192
79739565 193 nilfs->ns_cpfile = nilfs_cpfile_new(nilfs, checkpoint_size);
8a9d2191
RK		 194 if (unlikely(!nilfs->ns_cpfile))
195 goto failed_gc_dat;
196
79739565 197 nilfs->ns_sufile = nilfs_sufile_new(nilfs, segment_usage_size);
8a9d2191
RK		 198 if (unlikely(!nilfs->ns_sufile))
199 goto failed_cpfile;
200
8a9d2191 201 nilfs_mdt_set_shadow(nilfs->ns_dat, nilfs->ns_gc_dat);
8a9d2191 202
8707df38
RK		 203 err = nilfs_dat_read(nilfs->ns_dat, (void *)bh_sr->b_data +
204 NILFS_SR_DAT_OFFSET(inode_size));
8a9d2191
RK		 205 if (unlikely(err))
206 goto failed_sufile;
207
8707df38
RK		 208 err = nilfs_cpfile_read(nilfs->ns_cpfile, (void *)bh_sr->b_data +
209 NILFS_SR_CPFILE_OFFSET(inode_size));
8a9d2191
RK		 210 if (unlikely(err))
211 goto failed_sufile;
212
8707df38
RK		 213 err = nilfs_sufile_read(nilfs->ns_sufile, (void *)bh_sr->b_data +
214 NILFS_SR_SUFILE_OFFSET(inode_size));
8a9d2191
RK		 215 if (unlikely(err))
216 goto failed_sufile;
217
218 raw_sr = (struct nilfs_super_root *)bh_sr->b_data;
219 nilfs->ns_nongc_ctime = le64_to_cpu(raw_sr->sr_nongc_ctime);
220
221 failed:
222 brelse(bh_sr);
223 return err;
224
225 failed_sufile:
226 nilfs_mdt_destroy(nilfs->ns_sufile);
227
228 failed_cpfile:
229 nilfs_mdt_destroy(nilfs->ns_cpfile);
230
231 failed_gc_dat:
232 nilfs_mdt_destroy(nilfs->ns_gc_dat);
233
234 failed_dat:
235 nilfs_mdt_destroy(nilfs->ns_dat);
236 goto failed;
237}
238
239static void nilfs_init_recovery_info(struct nilfs_recovery_info *ri)
240{
241 memset(ri, 0, sizeof(*ri));
242 INIT_LIST_HEAD(&ri->ri_used_segments);
243}
244
245static void nilfs_clear_recovery_info(struct nilfs_recovery_info *ri)
246{
247 nilfs_dispose_segment_list(&ri->ri_used_segments);
248}
249
250/**
251 * load_nilfs - load and recover the nilfs
252 * @nilfs: the_nilfs structure to be released
253 * @sbi: nilfs_sb_info used to recover past segment
254 *
255 * load_nilfs() searches and load the latest super root,
256 * attaches the last segment, and does recovery if needed.
257 * The caller must call this exclusively for simultaneous mounts.
258 */
259int load_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi)
260{
261 struct nilfs_recovery_info ri;
262 unsigned int s_flags = sbi->s_super->s_flags;
263 int really_read_only = bdev_read_only(nilfs->ns_bdev);
a057d2c0 264 int valid_fs = nilfs_valid_fs(nilfs);
f50a4c81 265 int err;
8a9d2191 266
0234576d
RK		 267 if (nilfs_loaded(nilfs)) {
268 if (valid_fs ||
269 ((s_flags & MS_RDONLY) && nilfs_test_opt(sbi, NORECOVERY)))
270 return 0;
271 printk(KERN_ERR "NILFS: the filesystem is in an incomplete "
272 "recovery state.\n");
273 return -EINVAL;
274 }
8a9d2191 275
f50a4c81
RK		 276 if (!valid_fs) {
277 printk(KERN_WARNING "NILFS warning: mounting unchecked fs\n");
278 if (s_flags & MS_RDONLY) {
279 printk(KERN_INFO "NILFS: INFO: recovery "
280 "required for readonly filesystem.\n");
281 printk(KERN_INFO "NILFS: write access will "
282 "be enabled during recovery.\n");
8a9d2191 283 }
8a9d2191
RK		 284 }
285
f50a4c81
RK		 286 nilfs_init_recovery_info(&ri);
287
8a9d2191
RK		 288 err = nilfs_search_super_root(nilfs, sbi, &ri);
289 if (unlikely(err)) {
290 printk(KERN_ERR "NILFS: error searching super root.\n");
291 goto failed;
292 }
293
294 err = nilfs_load_super_root(nilfs, sbi, ri.ri_super_root);
295 if (unlikely(err)) {
296 printk(KERN_ERR "NILFS: error loading super root.\n");
297 goto failed;
298 }
299
f50a4c81
RK		 300 if (valid_fs)
301 goto skip_recovery;
302
303 if (s_flags & MS_RDONLY) {
0234576d
RK		 304 if (nilfs_test_opt(sbi, NORECOVERY)) {
305 printk(KERN_INFO "NILFS: norecovery option specified. "
306 "skipping roll-forward recovery\n");
307 goto skip_recovery;
308 }
f50a4c81
RK		 309 if (really_read_only) {
310 printk(KERN_ERR "NILFS: write access "
311 "unavailable, cannot proceed.\n");
312 err = -EROFS;
313 goto failed_unload;
8a9d2191 314 }
f50a4c81 315 sbi->s_super->s_flags &= ~MS_RDONLY;
0234576d
RK		 316 } else if (nilfs_test_opt(sbi, NORECOVERY)) {
317 printk(KERN_ERR "NILFS: recovery cancelled because norecovery "
318 "option was specified for a read/write mount\n");
319 err = -EINVAL;
320 goto failed_unload;
f50a4c81
RK		 321 }
322
323 err = nilfs_recover_logical_segments(nilfs, sbi, &ri);
324 if (err)
325 goto failed_unload;
326
327 down_write(&nilfs->ns_sem);
328 nilfs->ns_mount_state |= NILFS_VALID_FS;
329 nilfs->ns_sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state);
330 err = nilfs_commit_super(sbi, 1);
331 up_write(&nilfs->ns_sem);
332
333 if (err) {
334 printk(KERN_ERR "NILFS: failed to update super block. "
335 "recovery unfinished.\n");
336 goto failed_unload;
8a9d2191 337 }
f50a4c81 338 printk(KERN_INFO "NILFS: recovery complete.\n");
8a9d2191 339
f50a4c81 340 skip_recovery:
8a9d2191 341 set_nilfs_loaded(nilfs);
f50a4c81
RK		 342 nilfs_clear_recovery_info(&ri);
343 sbi->s_super->s_flags = s_flags;
344 return 0;
345
346 failed_unload:
347 nilfs_mdt_destroy(nilfs->ns_cpfile);
348 nilfs_mdt_destroy(nilfs->ns_sufile);
349 nilfs_mdt_destroy(nilfs->ns_dat);
8a9d2191
RK		 350
351 failed:
352 nilfs_clear_recovery_info(&ri);
353 sbi->s_super->s_flags = s_flags;
354 return err;
355}
356
357static unsigned long long nilfs_max_size(unsigned int blkbits)
358{
359 unsigned int max_bits;
360 unsigned long long res = MAX_LFS_FILESIZE; /* page cache limit */
361
362 max_bits = blkbits + NILFS_BMAP_KEY_BIT; /* bmap size limit */
363 if (max_bits < 64)
364 res = min_t(unsigned long long, res, (1ULL << max_bits) - 1);
365 return res;
366}
367
e339ad31
RK		 368static int nilfs_store_disk_layout(struct the_nilfs *nilfs,
369 struct nilfs_super_block *sbp)
8a9d2191
RK		 370{
371 if (le32_to_cpu(sbp->s_rev_level) != NILFS_CURRENT_REV) {
372 printk(KERN_ERR "NILFS: revision mismatch "
373 "(superblock rev.=%d.%d, current rev.=%d.%d). "
374 "Please check the version of mkfs.nilfs.\n",
375 le32_to_cpu(sbp->s_rev_level),
376 le16_to_cpu(sbp->s_minor_rev_level),
377 NILFS_CURRENT_REV, NILFS_MINOR_REV);
378 return -EINVAL;
379 }
e339ad31
RK		 380 nilfs->ns_sbsize = le16_to_cpu(sbp->s_bytes);
381 if (nilfs->ns_sbsize > BLOCK_SIZE)
382 return -EINVAL;
383
8a9d2191
RK		 384 nilfs->ns_inode_size = le16_to_cpu(sbp->s_inode_size);
385 nilfs->ns_first_ino = le32_to_cpu(sbp->s_first_ino);
386
387 nilfs->ns_blocks_per_segment = le32_to_cpu(sbp->s_blocks_per_segment);
388 if (nilfs->ns_blocks_per_segment < NILFS_SEG_MIN_BLOCKS) {
c91cea11 389 printk(KERN_ERR "NILFS: too short segment.\n");
8a9d2191
RK		 390 return -EINVAL;
391 }
392
393 nilfs->ns_first_data_block = le64_to_cpu(sbp->s_first_data_block);
394 nilfs->ns_nsegments = le64_to_cpu(sbp->s_nsegments);
395 nilfs->ns_r_segments_percentage =
396 le32_to_cpu(sbp->s_r_segments_percentage);
397 nilfs->ns_nrsvsegs =
398 max_t(unsigned long, NILFS_MIN_NRSVSEGS,
399 DIV_ROUND_UP(nilfs->ns_nsegments *
400 nilfs->ns_r_segments_percentage, 100));
401 nilfs->ns_crc_seed = le32_to_cpu(sbp->s_crc_seed);
402 return 0;
403}
404
e339ad31
RK		 405static int nilfs_valid_sb(struct nilfs_super_block *sbp)
406{
407 static unsigned char sum[4];
408 const int sumoff = offsetof(struct nilfs_super_block, s_sum);
409 size_t bytes;
410 u32 crc;
411
412 if (!sbp || le16_to_cpu(sbp->s_magic) != NILFS_SUPER_MAGIC)
413 return 0;
414 bytes = le16_to_cpu(sbp->s_bytes);
415 if (bytes > BLOCK_SIZE)
416 return 0;
417 crc = crc32_le(le32_to_cpu(sbp->s_crc_seed), (unsigned char *)sbp,
418 sumoff);
419 crc = crc32_le(crc, sum, 4);
420 crc = crc32_le(crc, (unsigned char *)sbp + sumoff + 4,
421 bytes - sumoff - 4);
422 return crc == le32_to_cpu(sbp->s_sum);
423}
424
425static int nilfs_sb2_bad_offset(struct nilfs_super_block *sbp, u64 offset)
426{
427 return offset < ((le64_to_cpu(sbp->s_nsegments) *
428 le32_to_cpu(sbp->s_blocks_per_segment)) <<
429 (le32_to_cpu(sbp->s_log_block_size) + 10));
430}
431
432static void nilfs_release_super_block(struct the_nilfs *nilfs)
433{
434 int i;
435
436 for (i = 0; i < 2; i++) {
437 if (nilfs->ns_sbp[i]) {
438 brelse(nilfs->ns_sbh[i]);
439 nilfs->ns_sbh[i] = NULL;
440 nilfs->ns_sbp[i] = NULL;
441 }
442 }
443}
444
445void nilfs_fall_back_super_block(struct the_nilfs *nilfs)
446{
447 brelse(nilfs->ns_sbh[0]);
448 nilfs->ns_sbh[0] = nilfs->ns_sbh[1];
449 nilfs->ns_sbp[0] = nilfs->ns_sbp[1];
450 nilfs->ns_sbh[1] = NULL;
451 nilfs->ns_sbp[1] = NULL;
452}
453
454void nilfs_swap_super_block(struct the_nilfs *nilfs)
455{
456 struct buffer_head *tsbh = nilfs->ns_sbh[0];
457 struct nilfs_super_block *tsbp = nilfs->ns_sbp[0];
458
459 nilfs->ns_sbh[0] = nilfs->ns_sbh[1];
460 nilfs->ns_sbp[0] = nilfs->ns_sbp[1];
461 nilfs->ns_sbh[1] = tsbh;
462 nilfs->ns_sbp[1] = tsbp;
463}
464
465static int nilfs_load_super_block(struct the_nilfs *nilfs,
466 struct super_block *sb, int blocksize,
467 struct nilfs_super_block **sbpp)
468{
469 struct nilfs_super_block **sbp = nilfs->ns_sbp;
470 struct buffer_head **sbh = nilfs->ns_sbh;
471 u64 sb2off = NILFS_SB2_OFFSET_BYTES(nilfs->ns_bdev->bd_inode->i_size);
472 int valid[2], swp = 0;
473
474 sbp[0] = nilfs_read_super_block(sb, NILFS_SB_OFFSET_BYTES, blocksize,
475 &sbh[0]);
476 sbp[1] = nilfs_read_super_block(sb, sb2off, blocksize, &sbh[1]);
477
478 if (!sbp[0]) {
479 if (!sbp[1]) {
480 printk(KERN_ERR "NILFS: unable to read superblock\n");
481 return -EIO;
482 }
483 printk(KERN_WARNING
484 "NILFS warning: unable to read primary superblock\n");
485 } else if (!sbp[1])
486 printk(KERN_WARNING
487 "NILFS warning: unable to read secondary superblock\n");
488
25294d8c
RK		 489 /*
490 * Compare two super blocks and set 1 in swp if the secondary
491 * super block is valid and newer. Otherwise, set 0 in swp.
492 */
e339ad31
RK		 493 valid[0] = nilfs_valid_sb(sbp[0]);
494 valid[1] = nilfs_valid_sb(sbp[1]);
25294d8c
RK		 495 swp = valid[1] && (!valid[0] ||
496 le64_to_cpu(sbp[1]->s_last_cno) >
497 le64_to_cpu(sbp[0]->s_last_cno));
e339ad31
RK		 498
499 if (valid[swp] && nilfs_sb2_bad_offset(sbp[swp], sb2off)) {
500 brelse(sbh[1]);
501 sbh[1] = NULL;
502 sbp[1] = NULL;
503 swp = 0;
504 }
505 if (!valid[swp]) {
506 nilfs_release_super_block(nilfs);
507 printk(KERN_ERR "NILFS: Can't find nilfs on dev %s.\n",
508 sb->s_id);
509 return -EINVAL;
510 }
511
512 if (swp) {
513 printk(KERN_WARNING "NILFS warning: broken superblock. "
514 "using spare superblock.\n");
515 nilfs_swap_super_block(nilfs);
516 }
517
518 nilfs->ns_sbwtime[0] = le64_to_cpu(sbp[0]->s_wtime);
519 nilfs->ns_sbwtime[1] = valid[!swp] ? le64_to_cpu(sbp[1]->s_wtime) : 0;
520 nilfs->ns_prot_seq = le64_to_cpu(sbp[valid[1] & !swp]->s_last_seq);
521 *sbpp = sbp[0];
522 return 0;
523}
524
8a9d2191
RK		 525/**
526 * init_nilfs - initialize a NILFS instance.
527 * @nilfs: the_nilfs structure
528 * @sbi: nilfs_sb_info
529 * @sb: super block
530 * @data: mount options
531 *
532 * init_nilfs() performs common initialization per block device (e.g.
533 * reading the super block, getting disk layout information, initializing
534 * shared fields in the_nilfs). It takes on some portion of the jobs
535 * typically done by a fill_super() routine. This division arises from
536 * the nature that multiple NILFS instances may be simultaneously
537 * mounted on a device.
538 * For multiple mounts on the same device, only the first mount
539 * invokes these tasks.
540 *
541 * Return Value: On success, 0 is returned. On error, a negative error
542 * code is returned.
543 */
544int init_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi, char *data)
545{
546 struct super_block *sb = sbi->s_super;
8a9d2191
RK		 547 struct nilfs_super_block *sbp;
548 struct backing_dev_info *bdi;
549 int blocksize;
e339ad31 550 int err;
8a9d2191
RK		 551
552 down_write(&nilfs->ns_sem);
553 if (nilfs_init(nilfs)) {
554 /* Load values from existing the_nilfs */
e339ad31 555 sbp = nilfs->ns_sbp[0];
8a9d2191
RK		 556 err = nilfs_store_magic_and_option(sb, sbp, data);
557 if (err)
558 goto out;
559
560 blocksize = BLOCK_SIZE << le32_to_cpu(sbp->s_log_block_size);
561 if (sb->s_blocksize != blocksize &&
562 !sb_set_blocksize(sb, blocksize)) {
563 printk(KERN_ERR "NILFS: blocksize %d unfit to device\n",
564 blocksize);
565 err = -EINVAL;
566 }
567 sb->s_maxbytes = nilfs_max_size(sb->s_blocksize_bits);
568 goto out;
569 }
570
e339ad31
RK		 571 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
572 if (!blocksize) {
573 printk(KERN_ERR "NILFS: unable to set blocksize\n");
8a9d2191
RK		 574 err = -EINVAL;
575 goto out;
576 }
e339ad31
RK		 577 err = nilfs_load_super_block(nilfs, sb, blocksize, &sbp);
578 if (err)
579 goto out;
580
8a9d2191
RK		 581 err = nilfs_store_magic_and_option(sb, sbp, data);
582 if (err)
583 goto failed_sbh;
584
585 blocksize = BLOCK_SIZE << le32_to_cpu(sbp->s_log_block_size);
586 if (sb->s_blocksize != blocksize) {
e1defc4f 587 int hw_blocksize = bdev_logical_block_size(sb->s_bdev);
e339ad31
RK		 588
589 if (blocksize < hw_blocksize) {
590 printk(KERN_ERR
591 "NILFS: blocksize %d too small for device "
592 "(sector-size = %d).\n",
593 blocksize, hw_blocksize);
8a9d2191 594 err = -EINVAL;
e339ad31
RK		 595 goto failed_sbh;
596 }
597 nilfs_release_super_block(nilfs);
598 sb_set_blocksize(sb, blocksize);
599
600 err = nilfs_load_super_block(nilfs, sb, blocksize, &sbp);
601 if (err)
8a9d2191
RK		 602 goto out;
603 /* not failed_sbh; sbh is released automatically
604 when reloading fails. */
8a9d2191
RK		 605 }
606 nilfs->ns_blocksize_bits = sb->s_blocksize_bits;
607
e339ad31 608 err = nilfs_store_disk_layout(nilfs, sbp);
8a9d2191
RK		 609 if (err)
610 goto failed_sbh;
611
612 sb->s_maxbytes = nilfs_max_size(sb->s_blocksize_bits);
613
614 nilfs->ns_mount_state = le16_to_cpu(sbp->s_state);
8a9d2191 615
2c96ce9f 616 bdi = nilfs->ns_bdev->bd_inode->i_mapping->backing_dev_info;
8a9d2191
RK		 617 nilfs->ns_bdi = bdi ? : &default_backing_dev_info;
618
619 /* Finding last segment */
620 nilfs->ns_last_pseg = le64_to_cpu(sbp->s_last_pseg);
621 nilfs->ns_last_cno = le64_to_cpu(sbp->s_last_cno);
622 nilfs->ns_last_seq = le64_to_cpu(sbp->s_last_seq);
623
624 nilfs->ns_seg_seq = nilfs->ns_last_seq;
625 nilfs->ns_segnum =
626 nilfs_get_segnum_of_block(nilfs, nilfs->ns_last_pseg);
627 nilfs->ns_cno = nilfs->ns_last_cno + 1;
628 if (nilfs->ns_segnum >= nilfs->ns_nsegments) {
629 printk(KERN_ERR "NILFS invalid last segment number.\n");
630 err = -EINVAL;
631 goto failed_sbh;
632 }
633 /* Dummy values */
634 nilfs->ns_free_segments_count =
635 nilfs->ns_nsegments - (nilfs->ns_segnum + 1);
636
637 /* Initialize gcinode cache */
638 err = nilfs_init_gccache(nilfs);
639 if (err)
640 goto failed_sbh;
641
642 set_nilfs_init(nilfs);
643 err = 0;
644 out:
645 up_write(&nilfs->ns_sem);
646 return err;
647
648 failed_sbh:
e339ad31 649 nilfs_release_super_block(nilfs);
8a9d2191
RK		 650 goto out;
651}
652
e902ec99
JS		 653int nilfs_discard_segments(struct the_nilfs *nilfs, __u64 *segnump,
654 size_t nsegs)
655{
656 sector_t seg_start, seg_end;
657 sector_t start = 0, nblocks = 0;
658 unsigned int sects_per_block;
659 __u64 *sn;
660 int ret = 0;
661
662 sects_per_block = (1 << nilfs->ns_blocksize_bits) /
663 bdev_logical_block_size(nilfs->ns_bdev);
664 for (sn = segnump; sn < segnump + nsegs; sn++) {
665 nilfs_get_segment_range(nilfs, *sn, &seg_start, &seg_end);
666
667 if (!nblocks) {
668 start = seg_start;
669 nblocks = seg_end - seg_start + 1;
670 } else if (start + nblocks == seg_start) {
671 nblocks += seg_end - seg_start + 1;
672 } else {
673 ret = blkdev_issue_discard(nilfs->ns_bdev,
674 start * sects_per_block,
675 nblocks * sects_per_block,
676 GFP_NOFS,
6a47dc14 677 BLKDEV_IFL_BARRIER);
e902ec99
JS		 678 if (ret < 0)
679 return ret;
680 nblocks = 0;
681 }
682 }
683 if (nblocks)
684 ret = blkdev_issue_discard(nilfs->ns_bdev,
685 start * sects_per_block,
686 nblocks * sects_per_block,
6a47dc14 687 GFP_NOFS, BLKDEV_IFL_BARRIER);
e902ec99
JS		 688 return ret;
689}
690
8a9d2191
RK		 691int nilfs_count_free_blocks(struct the_nilfs *nilfs, sector_t *nblocks)
692{
693 struct inode *dat = nilfs_dat_inode(nilfs);
694 unsigned long ncleansegs;
8a9d2191
RK		 695
696 down_read(&NILFS_MDT(dat)->mi_sem); /* XXX */
ef7d4757 697 ncleansegs = nilfs_sufile_get_ncleansegs(nilfs->ns_sufile);
8a9d2191 698 up_read(&NILFS_MDT(dat)->mi_sem); /* XXX */
ef7d4757
RK		 699 *nblocks = (sector_t)ncleansegs * nilfs->ns_blocks_per_segment;
700 return 0;
8a9d2191
RK		 701}
702
8a9d2191
RK		 703int nilfs_near_disk_full(struct the_nilfs *nilfs)
704{
8a9d2191 705 unsigned long ncleansegs, nincsegs;
ef7d4757
RK		 706
707 ncleansegs = nilfs_sufile_get_ncleansegs(nilfs->ns_sufile);
708 nincsegs = atomic_read(&nilfs->ns_ndirtyblks) /
709 nilfs->ns_blocks_per_segment + 1;
710
711 return ncleansegs <= nilfs->ns_nrsvsegs + nincsegs;
8a9d2191
RK		 712}
713
6dd47406
RK		 714/**
715 * nilfs_find_sbinfo - find existing nilfs_sb_info structure
716 * @nilfs: nilfs object
717 * @rw_mount: mount type (non-zero value for read/write mount)
718 * @cno: checkpoint number (zero for read-only mount)
719 *
720 * nilfs_find_sbinfo() returns the nilfs_sb_info structure which
721 * @rw_mount and @cno (in case of snapshots) matched. If no instance
722 * was found, NULL is returned. Although the super block instance can
723 * be unmounted after this function returns, the nilfs_sb_info struct
724 * is kept on memory until nilfs_put_sbinfo() is called.
725 */
726struct nilfs_sb_info *nilfs_find_sbinfo(struct the_nilfs *nilfs,
727 int rw_mount, __u64 cno)
728{
729 struct nilfs_sb_info *sbi;
730
e59399d0 731 down_read(&nilfs->ns_super_sem);
6dd47406
RK		 732 /*
733 * The SNAPSHOT flag and sb->s_flags are supposed to be
e59399d0 734 * protected with nilfs->ns_super_sem.
6dd47406
RK		 735 */
736 sbi = nilfs->ns_current;
737 if (rw_mount) {
738 if (sbi && !(sbi->s_super->s_flags & MS_RDONLY))
739 goto found; /* read/write mount */
740 else
741 goto out;
742 } else if (cno == 0) {
743 if (sbi && (sbi->s_super->s_flags & MS_RDONLY))
744 goto found; /* read-only mount */
745 else
746 goto out;
747 }
748
749 list_for_each_entry(sbi, &nilfs->ns_supers, s_list) {
750 if (nilfs_test_opt(sbi, SNAPSHOT) &&
751 sbi->s_snapshot_cno == cno)
752 goto found; /* snapshot mount */
753 }
754 out:
e59399d0 755 up_read(&nilfs->ns_super_sem);
6dd47406
RK		 756 return NULL;
757
758 found:
759 atomic_inc(&sbi->s_count);
e59399d0 760 up_read(&nilfs->ns_super_sem);
6dd47406
RK		 761 return sbi;
762}
763
8a9d2191
RK		 764int nilfs_checkpoint_is_mounted(struct the_nilfs *nilfs, __u64 cno,
765 int snapshot_mount)
766{
767 struct nilfs_sb_info *sbi;
768 int ret = 0;
769
e59399d0 770 down_read(&nilfs->ns_super_sem);
8a9d2191
RK		 771 if (cno == 0 || cno > nilfs->ns_cno)
772 goto out_unlock;
773
774 list_for_each_entry(sbi, &nilfs->ns_supers, s_list) {
775 if (sbi->s_snapshot_cno == cno &&
776 (!snapshot_mount || nilfs_test_opt(sbi, SNAPSHOT))) {
777 /* exclude read-only mounts */
778 ret++;
779 break;
780 }
781 }
782 /* for protecting recent checkpoints */
783 if (cno >= nilfs_last_cno(nilfs))
784 ret++;
785
786 out_unlock:
e59399d0 787 up_read(&nilfs->ns_super_sem);
8a9d2191
RK		 788 return ret;
789}
Clone of davem's net-next-2.6 tree