Commit | Line | Data |
---|---|---|
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 | |
38 | static LIST_HEAD(nilfs_objects); | |
39 | static DEFINE_SPINLOCK(nilfs_lock); | |
40 | ||
8a9d2191 RK |
41 | void 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 | 61 | static 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 | */ | |
96 | struct 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 | */ | |
131 | void 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 | ||
8b94025c | 162 | static int nilfs_load_super_root(struct the_nilfs *nilfs, sector_t sr_block) |
8a9d2191 RK |
163 | { |
164 | struct buffer_head *bh_sr; | |
165 | struct nilfs_super_root *raw_sr; | |
e339ad31 | 166 | struct nilfs_super_block **sbp = nilfs->ns_sbp; |
8a9d2191 RK |
167 | unsigned dat_entry_size, segment_usage_size, checkpoint_size; |
168 | unsigned inode_size; | |
169 | int err; | |
170 | ||
8b94025c | 171 | err = nilfs_read_super_root_block(nilfs, sr_block, &bh_sr, 1); |
8a9d2191 RK |
172 | if (unlikely(err)) |
173 | return err; | |
174 | ||
175 | down_read(&nilfs->ns_sem); | |
e339ad31 RK |
176 | dat_entry_size = le16_to_cpu(sbp[0]->s_dat_entry_size); |
177 | checkpoint_size = le16_to_cpu(sbp[0]->s_checkpoint_size); | |
178 | segment_usage_size = le16_to_cpu(sbp[0]->s_segment_usage_size); | |
8a9d2191 RK |
179 | up_read(&nilfs->ns_sem); |
180 | ||
181 | inode_size = nilfs->ns_inode_size; | |
182 | ||
183 | err = -ENOMEM; | |
79739565 | 184 | nilfs->ns_dat = nilfs_dat_new(nilfs, dat_entry_size); |
8a9d2191 RK |
185 | if (unlikely(!nilfs->ns_dat)) |
186 | goto failed; | |
187 | ||
79739565 | 188 | nilfs->ns_gc_dat = nilfs_dat_new(nilfs, dat_entry_size); |
8a9d2191 RK |
189 | if (unlikely(!nilfs->ns_gc_dat)) |
190 | goto failed_dat; | |
191 | ||
79739565 | 192 | nilfs->ns_cpfile = nilfs_cpfile_new(nilfs, checkpoint_size); |
8a9d2191 RK |
193 | if (unlikely(!nilfs->ns_cpfile)) |
194 | goto failed_gc_dat; | |
195 | ||
79739565 | 196 | nilfs->ns_sufile = nilfs_sufile_new(nilfs, segment_usage_size); |
8a9d2191 RK |
197 | if (unlikely(!nilfs->ns_sufile)) |
198 | goto failed_cpfile; | |
199 | ||
8a9d2191 | 200 | nilfs_mdt_set_shadow(nilfs->ns_dat, nilfs->ns_gc_dat); |
8a9d2191 | 201 | |
8707df38 RK |
202 | err = nilfs_dat_read(nilfs->ns_dat, (void *)bh_sr->b_data + |
203 | NILFS_SR_DAT_OFFSET(inode_size)); | |
8a9d2191 RK |
204 | if (unlikely(err)) |
205 | goto failed_sufile; | |
206 | ||
8707df38 RK |
207 | err = nilfs_cpfile_read(nilfs->ns_cpfile, (void *)bh_sr->b_data + |
208 | NILFS_SR_CPFILE_OFFSET(inode_size)); | |
8a9d2191 RK |
209 | if (unlikely(err)) |
210 | goto failed_sufile; | |
211 | ||
8707df38 RK |
212 | err = nilfs_sufile_read(nilfs->ns_sufile, (void *)bh_sr->b_data + |
213 | NILFS_SR_SUFILE_OFFSET(inode_size)); | |
8a9d2191 RK |
214 | if (unlikely(err)) |
215 | goto failed_sufile; | |
216 | ||
217 | raw_sr = (struct nilfs_super_root *)bh_sr->b_data; | |
218 | nilfs->ns_nongc_ctime = le64_to_cpu(raw_sr->sr_nongc_ctime); | |
219 | ||
220 | failed: | |
221 | brelse(bh_sr); | |
222 | return err; | |
223 | ||
224 | failed_sufile: | |
225 | nilfs_mdt_destroy(nilfs->ns_sufile); | |
226 | ||
227 | failed_cpfile: | |
228 | nilfs_mdt_destroy(nilfs->ns_cpfile); | |
229 | ||
230 | failed_gc_dat: | |
231 | nilfs_mdt_destroy(nilfs->ns_gc_dat); | |
232 | ||
233 | failed_dat: | |
234 | nilfs_mdt_destroy(nilfs->ns_dat); | |
235 | goto failed; | |
236 | } | |
237 | ||
238 | static void nilfs_init_recovery_info(struct nilfs_recovery_info *ri) | |
239 | { | |
240 | memset(ri, 0, sizeof(*ri)); | |
241 | INIT_LIST_HEAD(&ri->ri_used_segments); | |
242 | } | |
243 | ||
244 | static void nilfs_clear_recovery_info(struct nilfs_recovery_info *ri) | |
245 | { | |
246 | nilfs_dispose_segment_list(&ri->ri_used_segments); | |
247 | } | |
248 | ||
843d63ba RK |
249 | /** |
250 | * nilfs_store_log_cursor - load log cursor from a super block | |
251 | * @nilfs: nilfs object | |
252 | * @sbp: buffer storing super block to be read | |
253 | * | |
254 | * nilfs_store_log_cursor() reads the last position of the log | |
255 | * containing a super root from a given super block, and initializes | |
256 | * relevant information on the nilfs object preparatory for log | |
257 | * scanning and recovery. | |
258 | */ | |
259 | static int nilfs_store_log_cursor(struct the_nilfs *nilfs, | |
260 | struct nilfs_super_block *sbp) | |
261 | { | |
262 | int ret = 0; | |
263 | ||
264 | nilfs->ns_last_pseg = le64_to_cpu(sbp->s_last_pseg); | |
265 | nilfs->ns_last_cno = le64_to_cpu(sbp->s_last_cno); | |
266 | nilfs->ns_last_seq = le64_to_cpu(sbp->s_last_seq); | |
267 | ||
268 | nilfs->ns_seg_seq = nilfs->ns_last_seq; | |
269 | nilfs->ns_segnum = | |
270 | nilfs_get_segnum_of_block(nilfs, nilfs->ns_last_pseg); | |
271 | nilfs->ns_cno = nilfs->ns_last_cno + 1; | |
272 | if (nilfs->ns_segnum >= nilfs->ns_nsegments) { | |
273 | printk(KERN_ERR "NILFS invalid last segment number.\n"); | |
274 | ret = -EINVAL; | |
275 | } | |
276 | return ret; | |
277 | } | |
278 | ||
8a9d2191 RK |
279 | /** |
280 | * load_nilfs - load and recover the nilfs | |
281 | * @nilfs: the_nilfs structure to be released | |
282 | * @sbi: nilfs_sb_info used to recover past segment | |
283 | * | |
284 | * load_nilfs() searches and load the latest super root, | |
285 | * attaches the last segment, and does recovery if needed. | |
286 | * The caller must call this exclusively for simultaneous mounts. | |
287 | */ | |
288 | int load_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi) | |
289 | { | |
290 | struct nilfs_recovery_info ri; | |
291 | unsigned int s_flags = sbi->s_super->s_flags; | |
292 | int really_read_only = bdev_read_only(nilfs->ns_bdev); | |
a057d2c0 | 293 | int valid_fs = nilfs_valid_fs(nilfs); |
f50a4c81 | 294 | int err; |
8a9d2191 | 295 | |
0234576d RK |
296 | if (nilfs_loaded(nilfs)) { |
297 | if (valid_fs || | |
298 | ((s_flags & MS_RDONLY) && nilfs_test_opt(sbi, NORECOVERY))) | |
299 | return 0; | |
300 | printk(KERN_ERR "NILFS: the filesystem is in an incomplete " | |
301 | "recovery state.\n"); | |
302 | return -EINVAL; | |
303 | } | |
8a9d2191 | 304 | |
f50a4c81 RK |
305 | if (!valid_fs) { |
306 | printk(KERN_WARNING "NILFS warning: mounting unchecked fs\n"); | |
307 | if (s_flags & MS_RDONLY) { | |
308 | printk(KERN_INFO "NILFS: INFO: recovery " | |
309 | "required for readonly filesystem.\n"); | |
310 | printk(KERN_INFO "NILFS: write access will " | |
311 | "be enabled during recovery.\n"); | |
8a9d2191 | 312 | } |
8a9d2191 RK |
313 | } |
314 | ||
f50a4c81 RK |
315 | nilfs_init_recovery_info(&ri); |
316 | ||
8b94025c | 317 | err = nilfs_search_super_root(nilfs, &ri); |
8a9d2191 RK |
318 | if (unlikely(err)) { |
319 | printk(KERN_ERR "NILFS: error searching super root.\n"); | |
320 | goto failed; | |
321 | } | |
322 | ||
8b94025c | 323 | err = nilfs_load_super_root(nilfs, ri.ri_super_root); |
8a9d2191 RK |
324 | if (unlikely(err)) { |
325 | printk(KERN_ERR "NILFS: error loading super root.\n"); | |
326 | goto failed; | |
327 | } | |
328 | ||
f50a4c81 RK |
329 | if (valid_fs) |
330 | goto skip_recovery; | |
331 | ||
332 | if (s_flags & MS_RDONLY) { | |
0234576d RK |
333 | if (nilfs_test_opt(sbi, NORECOVERY)) { |
334 | printk(KERN_INFO "NILFS: norecovery option specified. " | |
335 | "skipping roll-forward recovery\n"); | |
336 | goto skip_recovery; | |
337 | } | |
f50a4c81 RK |
338 | if (really_read_only) { |
339 | printk(KERN_ERR "NILFS: write access " | |
340 | "unavailable, cannot proceed.\n"); | |
341 | err = -EROFS; | |
342 | goto failed_unload; | |
8a9d2191 | 343 | } |
f50a4c81 | 344 | sbi->s_super->s_flags &= ~MS_RDONLY; |
0234576d RK |
345 | } else if (nilfs_test_opt(sbi, NORECOVERY)) { |
346 | printk(KERN_ERR "NILFS: recovery cancelled because norecovery " | |
347 | "option was specified for a read/write mount\n"); | |
348 | err = -EINVAL; | |
349 | goto failed_unload; | |
f50a4c81 RK |
350 | } |
351 | ||
aee5ce2f | 352 | err = nilfs_salvage_orphan_logs(nilfs, sbi, &ri); |
f50a4c81 RK |
353 | if (err) |
354 | goto failed_unload; | |
355 | ||
356 | down_write(&nilfs->ns_sem); | |
7ecaa46c RK |
357 | nilfs->ns_mount_state |= NILFS_VALID_FS; /* set "clean" flag */ |
358 | err = nilfs_cleanup_super(sbi); | |
f50a4c81 RK |
359 | up_write(&nilfs->ns_sem); |
360 | ||
361 | if (err) { | |
362 | printk(KERN_ERR "NILFS: failed to update super block. " | |
363 | "recovery unfinished.\n"); | |
364 | goto failed_unload; | |
8a9d2191 | 365 | } |
f50a4c81 | 366 | printk(KERN_INFO "NILFS: recovery complete.\n"); |
8a9d2191 | 367 | |
f50a4c81 | 368 | skip_recovery: |
8a9d2191 | 369 | set_nilfs_loaded(nilfs); |
f50a4c81 RK |
370 | nilfs_clear_recovery_info(&ri); |
371 | sbi->s_super->s_flags = s_flags; | |
372 | return 0; | |
373 | ||
374 | failed_unload: | |
375 | nilfs_mdt_destroy(nilfs->ns_cpfile); | |
376 | nilfs_mdt_destroy(nilfs->ns_sufile); | |
377 | nilfs_mdt_destroy(nilfs->ns_dat); | |
8a9d2191 RK |
378 | |
379 | failed: | |
380 | nilfs_clear_recovery_info(&ri); | |
381 | sbi->s_super->s_flags = s_flags; | |
382 | return err; | |
383 | } | |
384 | ||
385 | static unsigned long long nilfs_max_size(unsigned int blkbits) | |
386 | { | |
387 | unsigned int max_bits; | |
388 | unsigned long long res = MAX_LFS_FILESIZE; /* page cache limit */ | |
389 | ||
390 | max_bits = blkbits + NILFS_BMAP_KEY_BIT; /* bmap size limit */ | |
391 | if (max_bits < 64) | |
392 | res = min_t(unsigned long long, res, (1ULL << max_bits) - 1); | |
393 | return res; | |
394 | } | |
395 | ||
e339ad31 RK |
396 | static int nilfs_store_disk_layout(struct the_nilfs *nilfs, |
397 | struct nilfs_super_block *sbp) | |
8a9d2191 RK |
398 | { |
399 | if (le32_to_cpu(sbp->s_rev_level) != NILFS_CURRENT_REV) { | |
400 | printk(KERN_ERR "NILFS: revision mismatch " | |
401 | "(superblock rev.=%d.%d, current rev.=%d.%d). " | |
402 | "Please check the version of mkfs.nilfs.\n", | |
403 | le32_to_cpu(sbp->s_rev_level), | |
404 | le16_to_cpu(sbp->s_minor_rev_level), | |
405 | NILFS_CURRENT_REV, NILFS_MINOR_REV); | |
406 | return -EINVAL; | |
407 | } | |
e339ad31 RK |
408 | nilfs->ns_sbsize = le16_to_cpu(sbp->s_bytes); |
409 | if (nilfs->ns_sbsize > BLOCK_SIZE) | |
410 | return -EINVAL; | |
411 | ||
8a9d2191 RK |
412 | nilfs->ns_inode_size = le16_to_cpu(sbp->s_inode_size); |
413 | nilfs->ns_first_ino = le32_to_cpu(sbp->s_first_ino); | |
414 | ||
415 | nilfs->ns_blocks_per_segment = le32_to_cpu(sbp->s_blocks_per_segment); | |
416 | if (nilfs->ns_blocks_per_segment < NILFS_SEG_MIN_BLOCKS) { | |
c91cea11 | 417 | printk(KERN_ERR "NILFS: too short segment.\n"); |
8a9d2191 RK |
418 | return -EINVAL; |
419 | } | |
420 | ||
421 | nilfs->ns_first_data_block = le64_to_cpu(sbp->s_first_data_block); | |
422 | nilfs->ns_nsegments = le64_to_cpu(sbp->s_nsegments); | |
423 | nilfs->ns_r_segments_percentage = | |
424 | le32_to_cpu(sbp->s_r_segments_percentage); | |
425 | nilfs->ns_nrsvsegs = | |
426 | max_t(unsigned long, NILFS_MIN_NRSVSEGS, | |
427 | DIV_ROUND_UP(nilfs->ns_nsegments * | |
428 | nilfs->ns_r_segments_percentage, 100)); | |
429 | nilfs->ns_crc_seed = le32_to_cpu(sbp->s_crc_seed); | |
430 | return 0; | |
431 | } | |
432 | ||
e339ad31 RK |
433 | static int nilfs_valid_sb(struct nilfs_super_block *sbp) |
434 | { | |
435 | static unsigned char sum[4]; | |
436 | const int sumoff = offsetof(struct nilfs_super_block, s_sum); | |
437 | size_t bytes; | |
438 | u32 crc; | |
439 | ||
440 | if (!sbp || le16_to_cpu(sbp->s_magic) != NILFS_SUPER_MAGIC) | |
441 | return 0; | |
442 | bytes = le16_to_cpu(sbp->s_bytes); | |
443 | if (bytes > BLOCK_SIZE) | |
444 | return 0; | |
445 | crc = crc32_le(le32_to_cpu(sbp->s_crc_seed), (unsigned char *)sbp, | |
446 | sumoff); | |
447 | crc = crc32_le(crc, sum, 4); | |
448 | crc = crc32_le(crc, (unsigned char *)sbp + sumoff + 4, | |
449 | bytes - sumoff - 4); | |
450 | return crc == le32_to_cpu(sbp->s_sum); | |
451 | } | |
452 | ||
453 | static int nilfs_sb2_bad_offset(struct nilfs_super_block *sbp, u64 offset) | |
454 | { | |
455 | return offset < ((le64_to_cpu(sbp->s_nsegments) * | |
456 | le32_to_cpu(sbp->s_blocks_per_segment)) << | |
457 | (le32_to_cpu(sbp->s_log_block_size) + 10)); | |
458 | } | |
459 | ||
460 | static void nilfs_release_super_block(struct the_nilfs *nilfs) | |
461 | { | |
462 | int i; | |
463 | ||
464 | for (i = 0; i < 2; i++) { | |
465 | if (nilfs->ns_sbp[i]) { | |
466 | brelse(nilfs->ns_sbh[i]); | |
467 | nilfs->ns_sbh[i] = NULL; | |
468 | nilfs->ns_sbp[i] = NULL; | |
469 | } | |
470 | } | |
471 | } | |
472 | ||
473 | void nilfs_fall_back_super_block(struct the_nilfs *nilfs) | |
474 | { | |
475 | brelse(nilfs->ns_sbh[0]); | |
476 | nilfs->ns_sbh[0] = nilfs->ns_sbh[1]; | |
477 | nilfs->ns_sbp[0] = nilfs->ns_sbp[1]; | |
478 | nilfs->ns_sbh[1] = NULL; | |
479 | nilfs->ns_sbp[1] = NULL; | |
480 | } | |
481 | ||
482 | void nilfs_swap_super_block(struct the_nilfs *nilfs) | |
483 | { | |
484 | struct buffer_head *tsbh = nilfs->ns_sbh[0]; | |
485 | struct nilfs_super_block *tsbp = nilfs->ns_sbp[0]; | |
486 | ||
487 | nilfs->ns_sbh[0] = nilfs->ns_sbh[1]; | |
488 | nilfs->ns_sbp[0] = nilfs->ns_sbp[1]; | |
489 | nilfs->ns_sbh[1] = tsbh; | |
490 | nilfs->ns_sbp[1] = tsbp; | |
491 | } | |
492 | ||
493 | static int nilfs_load_super_block(struct the_nilfs *nilfs, | |
494 | struct super_block *sb, int blocksize, | |
495 | struct nilfs_super_block **sbpp) | |
496 | { | |
497 | struct nilfs_super_block **sbp = nilfs->ns_sbp; | |
498 | struct buffer_head **sbh = nilfs->ns_sbh; | |
499 | u64 sb2off = NILFS_SB2_OFFSET_BYTES(nilfs->ns_bdev->bd_inode->i_size); | |
500 | int valid[2], swp = 0; | |
501 | ||
502 | sbp[0] = nilfs_read_super_block(sb, NILFS_SB_OFFSET_BYTES, blocksize, | |
503 | &sbh[0]); | |
504 | sbp[1] = nilfs_read_super_block(sb, sb2off, blocksize, &sbh[1]); | |
505 | ||
506 | if (!sbp[0]) { | |
507 | if (!sbp[1]) { | |
508 | printk(KERN_ERR "NILFS: unable to read superblock\n"); | |
509 | return -EIO; | |
510 | } | |
511 | printk(KERN_WARNING | |
512 | "NILFS warning: unable to read primary superblock\n"); | |
513 | } else if (!sbp[1]) | |
514 | printk(KERN_WARNING | |
515 | "NILFS warning: unable to read secondary superblock\n"); | |
516 | ||
25294d8c RK |
517 | /* |
518 | * Compare two super blocks and set 1 in swp if the secondary | |
519 | * super block is valid and newer. Otherwise, set 0 in swp. | |
520 | */ | |
e339ad31 RK |
521 | valid[0] = nilfs_valid_sb(sbp[0]); |
522 | valid[1] = nilfs_valid_sb(sbp[1]); | |
25294d8c RK |
523 | swp = valid[1] && (!valid[0] || |
524 | le64_to_cpu(sbp[1]->s_last_cno) > | |
525 | le64_to_cpu(sbp[0]->s_last_cno)); | |
e339ad31 RK |
526 | |
527 | if (valid[swp] && nilfs_sb2_bad_offset(sbp[swp], sb2off)) { | |
528 | brelse(sbh[1]); | |
529 | sbh[1] = NULL; | |
530 | sbp[1] = NULL; | |
531 | swp = 0; | |
532 | } | |
533 | if (!valid[swp]) { | |
534 | nilfs_release_super_block(nilfs); | |
535 | printk(KERN_ERR "NILFS: Can't find nilfs on dev %s.\n", | |
536 | sb->s_id); | |
537 | return -EINVAL; | |
538 | } | |
539 | ||
540 | if (swp) { | |
541 | printk(KERN_WARNING "NILFS warning: broken superblock. " | |
542 | "using spare superblock.\n"); | |
543 | nilfs_swap_super_block(nilfs); | |
544 | } | |
545 | ||
b2ac86e1 JS |
546 | nilfs->ns_sbwcount = 0; |
547 | nilfs->ns_sbwtime = le64_to_cpu(sbp[0]->s_wtime); | |
e339ad31 RK |
548 | nilfs->ns_prot_seq = le64_to_cpu(sbp[valid[1] & !swp]->s_last_seq); |
549 | *sbpp = sbp[0]; | |
550 | return 0; | |
551 | } | |
552 | ||
8a9d2191 RK |
553 | /** |
554 | * init_nilfs - initialize a NILFS instance. | |
555 | * @nilfs: the_nilfs structure | |
556 | * @sbi: nilfs_sb_info | |
557 | * @sb: super block | |
558 | * @data: mount options | |
559 | * | |
560 | * init_nilfs() performs common initialization per block device (e.g. | |
561 | * reading the super block, getting disk layout information, initializing | |
562 | * shared fields in the_nilfs). It takes on some portion of the jobs | |
563 | * typically done by a fill_super() routine. This division arises from | |
564 | * the nature that multiple NILFS instances may be simultaneously | |
565 | * mounted on a device. | |
566 | * For multiple mounts on the same device, only the first mount | |
567 | * invokes these tasks. | |
568 | * | |
569 | * Return Value: On success, 0 is returned. On error, a negative error | |
570 | * code is returned. | |
571 | */ | |
572 | int init_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi, char *data) | |
573 | { | |
574 | struct super_block *sb = sbi->s_super; | |
8a9d2191 RK |
575 | struct nilfs_super_block *sbp; |
576 | struct backing_dev_info *bdi; | |
577 | int blocksize; | |
e339ad31 | 578 | int err; |
8a9d2191 RK |
579 | |
580 | down_write(&nilfs->ns_sem); | |
581 | if (nilfs_init(nilfs)) { | |
582 | /* Load values from existing the_nilfs */ | |
e339ad31 | 583 | sbp = nilfs->ns_sbp[0]; |
8a9d2191 RK |
584 | err = nilfs_store_magic_and_option(sb, sbp, data); |
585 | if (err) | |
586 | goto out; | |
587 | ||
588 | blocksize = BLOCK_SIZE << le32_to_cpu(sbp->s_log_block_size); | |
589 | if (sb->s_blocksize != blocksize && | |
590 | !sb_set_blocksize(sb, blocksize)) { | |
591 | printk(KERN_ERR "NILFS: blocksize %d unfit to device\n", | |
592 | blocksize); | |
593 | err = -EINVAL; | |
594 | } | |
595 | sb->s_maxbytes = nilfs_max_size(sb->s_blocksize_bits); | |
596 | goto out; | |
597 | } | |
598 | ||
e339ad31 RK |
599 | blocksize = sb_min_blocksize(sb, BLOCK_SIZE); |
600 | if (!blocksize) { | |
601 | printk(KERN_ERR "NILFS: unable to set blocksize\n"); | |
8a9d2191 RK |
602 | err = -EINVAL; |
603 | goto out; | |
604 | } | |
e339ad31 RK |
605 | err = nilfs_load_super_block(nilfs, sb, blocksize, &sbp); |
606 | if (err) | |
607 | goto out; | |
608 | ||
8a9d2191 RK |
609 | err = nilfs_store_magic_and_option(sb, sbp, data); |
610 | if (err) | |
611 | goto failed_sbh; | |
612 | ||
613 | blocksize = BLOCK_SIZE << le32_to_cpu(sbp->s_log_block_size); | |
614 | if (sb->s_blocksize != blocksize) { | |
e1defc4f | 615 | int hw_blocksize = bdev_logical_block_size(sb->s_bdev); |
e339ad31 RK |
616 | |
617 | if (blocksize < hw_blocksize) { | |
618 | printk(KERN_ERR | |
619 | "NILFS: blocksize %d too small for device " | |
620 | "(sector-size = %d).\n", | |
621 | blocksize, hw_blocksize); | |
8a9d2191 | 622 | err = -EINVAL; |
e339ad31 RK |
623 | goto failed_sbh; |
624 | } | |
625 | nilfs_release_super_block(nilfs); | |
626 | sb_set_blocksize(sb, blocksize); | |
627 | ||
628 | err = nilfs_load_super_block(nilfs, sb, blocksize, &sbp); | |
629 | if (err) | |
8a9d2191 RK |
630 | goto out; |
631 | /* not failed_sbh; sbh is released automatically | |
632 | when reloading fails. */ | |
8a9d2191 RK |
633 | } |
634 | nilfs->ns_blocksize_bits = sb->s_blocksize_bits; | |
92c60cca | 635 | nilfs->ns_blocksize = blocksize; |
8a9d2191 | 636 | |
e339ad31 | 637 | err = nilfs_store_disk_layout(nilfs, sbp); |
8a9d2191 RK |
638 | if (err) |
639 | goto failed_sbh; | |
640 | ||
641 | sb->s_maxbytes = nilfs_max_size(sb->s_blocksize_bits); | |
642 | ||
643 | nilfs->ns_mount_state = le16_to_cpu(sbp->s_state); | |
8a9d2191 | 644 | |
2c96ce9f | 645 | bdi = nilfs->ns_bdev->bd_inode->i_mapping->backing_dev_info; |
8a9d2191 RK |
646 | nilfs->ns_bdi = bdi ? : &default_backing_dev_info; |
647 | ||
843d63ba RK |
648 | err = nilfs_store_log_cursor(nilfs, sbp); |
649 | if (err) | |
8a9d2191 | 650 | goto failed_sbh; |
8a9d2191 RK |
651 | |
652 | /* Initialize gcinode cache */ | |
653 | err = nilfs_init_gccache(nilfs); | |
654 | if (err) | |
655 | goto failed_sbh; | |
656 | ||
657 | set_nilfs_init(nilfs); | |
658 | err = 0; | |
659 | out: | |
660 | up_write(&nilfs->ns_sem); | |
661 | return err; | |
662 | ||
663 | failed_sbh: | |
e339ad31 | 664 | nilfs_release_super_block(nilfs); |
8a9d2191 RK |
665 | goto out; |
666 | } | |
667 | ||
e902ec99 JS |
668 | int nilfs_discard_segments(struct the_nilfs *nilfs, __u64 *segnump, |
669 | size_t nsegs) | |
670 | { | |
671 | sector_t seg_start, seg_end; | |
672 | sector_t start = 0, nblocks = 0; | |
673 | unsigned int sects_per_block; | |
674 | __u64 *sn; | |
675 | int ret = 0; | |
676 | ||
677 | sects_per_block = (1 << nilfs->ns_blocksize_bits) / | |
678 | bdev_logical_block_size(nilfs->ns_bdev); | |
679 | for (sn = segnump; sn < segnump + nsegs; sn++) { | |
680 | nilfs_get_segment_range(nilfs, *sn, &seg_start, &seg_end); | |
681 | ||
682 | if (!nblocks) { | |
683 | start = seg_start; | |
684 | nblocks = seg_end - seg_start + 1; | |
685 | } else if (start + nblocks == seg_start) { | |
686 | nblocks += seg_end - seg_start + 1; | |
687 | } else { | |
688 | ret = blkdev_issue_discard(nilfs->ns_bdev, | |
689 | start * sects_per_block, | |
690 | nblocks * sects_per_block, | |
691 | GFP_NOFS, | |
6a47dc14 | 692 | BLKDEV_IFL_BARRIER); |
e902ec99 JS |
693 | if (ret < 0) |
694 | return ret; | |
695 | nblocks = 0; | |
696 | } | |
697 | } | |
698 | if (nblocks) | |
699 | ret = blkdev_issue_discard(nilfs->ns_bdev, | |
700 | start * sects_per_block, | |
701 | nblocks * sects_per_block, | |
6a47dc14 | 702 | GFP_NOFS, BLKDEV_IFL_BARRIER); |
e902ec99 JS |
703 | return ret; |
704 | } | |
705 | ||
8a9d2191 RK |
706 | int nilfs_count_free_blocks(struct the_nilfs *nilfs, sector_t *nblocks) |
707 | { | |
708 | struct inode *dat = nilfs_dat_inode(nilfs); | |
709 | unsigned long ncleansegs; | |
8a9d2191 RK |
710 | |
711 | down_read(&NILFS_MDT(dat)->mi_sem); /* XXX */ | |
ef7d4757 | 712 | ncleansegs = nilfs_sufile_get_ncleansegs(nilfs->ns_sufile); |
8a9d2191 | 713 | up_read(&NILFS_MDT(dat)->mi_sem); /* XXX */ |
ef7d4757 RK |
714 | *nblocks = (sector_t)ncleansegs * nilfs->ns_blocks_per_segment; |
715 | return 0; | |
8a9d2191 RK |
716 | } |
717 | ||
8a9d2191 RK |
718 | int nilfs_near_disk_full(struct the_nilfs *nilfs) |
719 | { | |
8a9d2191 | 720 | unsigned long ncleansegs, nincsegs; |
ef7d4757 RK |
721 | |
722 | ncleansegs = nilfs_sufile_get_ncleansegs(nilfs->ns_sufile); | |
723 | nincsegs = atomic_read(&nilfs->ns_ndirtyblks) / | |
724 | nilfs->ns_blocks_per_segment + 1; | |
725 | ||
726 | return ncleansegs <= nilfs->ns_nrsvsegs + nincsegs; | |
8a9d2191 RK |
727 | } |
728 | ||
6dd47406 RK |
729 | /** |
730 | * nilfs_find_sbinfo - find existing nilfs_sb_info structure | |
731 | * @nilfs: nilfs object | |
732 | * @rw_mount: mount type (non-zero value for read/write mount) | |
733 | * @cno: checkpoint number (zero for read-only mount) | |
734 | * | |
735 | * nilfs_find_sbinfo() returns the nilfs_sb_info structure which | |
736 | * @rw_mount and @cno (in case of snapshots) matched. If no instance | |
737 | * was found, NULL is returned. Although the super block instance can | |
738 | * be unmounted after this function returns, the nilfs_sb_info struct | |
739 | * is kept on memory until nilfs_put_sbinfo() is called. | |
740 | */ | |
741 | struct nilfs_sb_info *nilfs_find_sbinfo(struct the_nilfs *nilfs, | |
742 | int rw_mount, __u64 cno) | |
743 | { | |
744 | struct nilfs_sb_info *sbi; | |
745 | ||
e59399d0 | 746 | down_read(&nilfs->ns_super_sem); |
6dd47406 RK |
747 | /* |
748 | * The SNAPSHOT flag and sb->s_flags are supposed to be | |
e59399d0 | 749 | * protected with nilfs->ns_super_sem. |
6dd47406 RK |
750 | */ |
751 | sbi = nilfs->ns_current; | |
752 | if (rw_mount) { | |
753 | if (sbi && !(sbi->s_super->s_flags & MS_RDONLY)) | |
754 | goto found; /* read/write mount */ | |
755 | else | |
756 | goto out; | |
757 | } else if (cno == 0) { | |
758 | if (sbi && (sbi->s_super->s_flags & MS_RDONLY)) | |
759 | goto found; /* read-only mount */ | |
760 | else | |
761 | goto out; | |
762 | } | |
763 | ||
764 | list_for_each_entry(sbi, &nilfs->ns_supers, s_list) { | |
765 | if (nilfs_test_opt(sbi, SNAPSHOT) && | |
766 | sbi->s_snapshot_cno == cno) | |
767 | goto found; /* snapshot mount */ | |
768 | } | |
769 | out: | |
e59399d0 | 770 | up_read(&nilfs->ns_super_sem); |
6dd47406 RK |
771 | return NULL; |
772 | ||
773 | found: | |
774 | atomic_inc(&sbi->s_count); | |
e59399d0 | 775 | up_read(&nilfs->ns_super_sem); |
6dd47406 RK |
776 | return sbi; |
777 | } | |
778 | ||
8a9d2191 RK |
779 | int nilfs_checkpoint_is_mounted(struct the_nilfs *nilfs, __u64 cno, |
780 | int snapshot_mount) | |
781 | { | |
782 | struct nilfs_sb_info *sbi; | |
783 | int ret = 0; | |
784 | ||
e59399d0 | 785 | down_read(&nilfs->ns_super_sem); |
8a9d2191 RK |
786 | if (cno == 0 || cno > nilfs->ns_cno) |
787 | goto out_unlock; | |
788 | ||
789 | list_for_each_entry(sbi, &nilfs->ns_supers, s_list) { | |
790 | if (sbi->s_snapshot_cno == cno && | |
791 | (!snapshot_mount || nilfs_test_opt(sbi, SNAPSHOT))) { | |
792 | /* exclude read-only mounts */ | |
793 | ret++; | |
794 | break; | |
795 | } | |
796 | } | |
797 | /* for protecting recent checkpoints */ | |
798 | if (cno >= nilfs_last_cno(nilfs)) | |
799 | ret++; | |
800 | ||
801 | out_unlock: | |
e59399d0 | 802 | up_read(&nilfs->ns_super_sem); |
8a9d2191 RK |
803 | return ret; |
804 | } |