Commit | Line | Data |
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29619809 KS |
1 | /* |
2 | * cpfile.c - NILFS checkpoint file. | |
3 | * | |
4 | * Copyright (C) 2006-2008 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 Koji Sato <koji@osrg.net>. | |
21 | */ | |
22 | ||
23 | #include <linux/kernel.h> | |
24 | #include <linux/fs.h> | |
25 | #include <linux/string.h> | |
26 | #include <linux/buffer_head.h> | |
27 | #include <linux/errno.h> | |
28 | #include <linux/nilfs2_fs.h> | |
29 | #include "mdt.h" | |
30 | #include "cpfile.h" | |
31 | ||
32 | ||
33 | static inline unsigned long | |
34 | nilfs_cpfile_checkpoints_per_block(const struct inode *cpfile) | |
35 | { | |
36 | return NILFS_MDT(cpfile)->mi_entries_per_block; | |
37 | } | |
38 | ||
39 | /* block number from the beginning of the file */ | |
40 | static unsigned long | |
41 | nilfs_cpfile_get_blkoff(const struct inode *cpfile, __u64 cno) | |
42 | { | |
1f5abe7e | 43 | __u64 tcno = cno + NILFS_MDT(cpfile)->mi_first_entry_offset - 1; |
29619809 KS |
44 | do_div(tcno, nilfs_cpfile_checkpoints_per_block(cpfile)); |
45 | return (unsigned long)tcno; | |
46 | } | |
47 | ||
48 | /* offset in block */ | |
49 | static unsigned long | |
50 | nilfs_cpfile_get_offset(const struct inode *cpfile, __u64 cno) | |
51 | { | |
52 | __u64 tcno = cno + NILFS_MDT(cpfile)->mi_first_entry_offset - 1; | |
53 | return do_div(tcno, nilfs_cpfile_checkpoints_per_block(cpfile)); | |
54 | } | |
55 | ||
56 | static unsigned long | |
57 | nilfs_cpfile_checkpoints_in_block(const struct inode *cpfile, | |
58 | __u64 curr, | |
59 | __u64 max) | |
60 | { | |
61 | return min_t(__u64, | |
62 | nilfs_cpfile_checkpoints_per_block(cpfile) - | |
63 | nilfs_cpfile_get_offset(cpfile, curr), | |
64 | max - curr); | |
65 | } | |
66 | ||
67 | static inline int nilfs_cpfile_is_in_first(const struct inode *cpfile, | |
68 | __u64 cno) | |
69 | { | |
70 | return nilfs_cpfile_get_blkoff(cpfile, cno) == 0; | |
71 | } | |
72 | ||
73 | static unsigned int | |
74 | nilfs_cpfile_block_add_valid_checkpoints(const struct inode *cpfile, | |
75 | struct buffer_head *bh, | |
76 | void *kaddr, | |
77 | unsigned int n) | |
78 | { | |
79 | struct nilfs_checkpoint *cp = kaddr + bh_offset(bh); | |
80 | unsigned int count; | |
81 | ||
82 | count = le32_to_cpu(cp->cp_checkpoints_count) + n; | |
83 | cp->cp_checkpoints_count = cpu_to_le32(count); | |
84 | return count; | |
85 | } | |
86 | ||
87 | static unsigned int | |
88 | nilfs_cpfile_block_sub_valid_checkpoints(const struct inode *cpfile, | |
89 | struct buffer_head *bh, | |
90 | void *kaddr, | |
91 | unsigned int n) | |
92 | { | |
93 | struct nilfs_checkpoint *cp = kaddr + bh_offset(bh); | |
94 | unsigned int count; | |
95 | ||
1f5abe7e | 96 | WARN_ON(le32_to_cpu(cp->cp_checkpoints_count) < n); |
29619809 KS |
97 | count = le32_to_cpu(cp->cp_checkpoints_count) - n; |
98 | cp->cp_checkpoints_count = cpu_to_le32(count); | |
99 | return count; | |
100 | } | |
101 | ||
102 | static inline struct nilfs_cpfile_header * | |
103 | nilfs_cpfile_block_get_header(const struct inode *cpfile, | |
104 | struct buffer_head *bh, | |
105 | void *kaddr) | |
106 | { | |
107 | return kaddr + bh_offset(bh); | |
108 | } | |
109 | ||
110 | static struct nilfs_checkpoint * | |
111 | nilfs_cpfile_block_get_checkpoint(const struct inode *cpfile, __u64 cno, | |
112 | struct buffer_head *bh, | |
113 | void *kaddr) | |
114 | { | |
115 | return kaddr + bh_offset(bh) + nilfs_cpfile_get_offset(cpfile, cno) * | |
116 | NILFS_MDT(cpfile)->mi_entry_size; | |
117 | } | |
118 | ||
119 | static void nilfs_cpfile_block_init(struct inode *cpfile, | |
120 | struct buffer_head *bh, | |
121 | void *kaddr) | |
122 | { | |
123 | struct nilfs_checkpoint *cp = kaddr + bh_offset(bh); | |
124 | size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size; | |
125 | int n = nilfs_cpfile_checkpoints_per_block(cpfile); | |
126 | ||
127 | while (n-- > 0) { | |
128 | nilfs_checkpoint_set_invalid(cp); | |
129 | cp = (void *)cp + cpsz; | |
130 | } | |
131 | } | |
132 | ||
133 | static inline int nilfs_cpfile_get_header_block(struct inode *cpfile, | |
134 | struct buffer_head **bhp) | |
135 | { | |
136 | return nilfs_mdt_get_block(cpfile, 0, 0, NULL, bhp); | |
137 | } | |
138 | ||
139 | static inline int nilfs_cpfile_get_checkpoint_block(struct inode *cpfile, | |
140 | __u64 cno, | |
141 | int create, | |
142 | struct buffer_head **bhp) | |
143 | { | |
144 | return nilfs_mdt_get_block(cpfile, | |
145 | nilfs_cpfile_get_blkoff(cpfile, cno), | |
146 | create, nilfs_cpfile_block_init, bhp); | |
147 | } | |
148 | ||
149 | static inline int nilfs_cpfile_delete_checkpoint_block(struct inode *cpfile, | |
150 | __u64 cno) | |
151 | { | |
152 | return nilfs_mdt_delete_block(cpfile, | |
153 | nilfs_cpfile_get_blkoff(cpfile, cno)); | |
154 | } | |
155 | ||
156 | /** | |
157 | * nilfs_cpfile_get_checkpoint - get a checkpoint | |
158 | * @cpfile: inode of checkpoint file | |
159 | * @cno: checkpoint number | |
160 | * @create: create flag | |
161 | * @cpp: pointer to a checkpoint | |
162 | * @bhp: pointer to a buffer head | |
163 | * | |
164 | * Description: nilfs_cpfile_get_checkpoint() acquires the checkpoint | |
165 | * specified by @cno. A new checkpoint will be created if @cno is the current | |
166 | * checkpoint number and @create is nonzero. | |
167 | * | |
168 | * Return Value: On success, 0 is returned, and the checkpoint and the | |
169 | * buffer head of the buffer on which the checkpoint is located are stored in | |
170 | * the place pointed by @cpp and @bhp, respectively. On error, one of the | |
171 | * following negative error codes is returned. | |
172 | * | |
173 | * %-EIO - I/O error. | |
174 | * | |
175 | * %-ENOMEM - Insufficient amount of memory available. | |
176 | * | |
177 | * %-ENOENT - No such checkpoint. | |
1f5abe7e RK |
178 | * |
179 | * %-EINVAL - invalid checkpoint. | |
29619809 KS |
180 | */ |
181 | int nilfs_cpfile_get_checkpoint(struct inode *cpfile, | |
182 | __u64 cno, | |
183 | int create, | |
184 | struct nilfs_checkpoint **cpp, | |
185 | struct buffer_head **bhp) | |
186 | { | |
187 | struct buffer_head *header_bh, *cp_bh; | |
188 | struct nilfs_cpfile_header *header; | |
189 | struct nilfs_checkpoint *cp; | |
190 | void *kaddr; | |
191 | int ret; | |
192 | ||
1f5abe7e RK |
193 | if (unlikely(cno < 1 || cno > nilfs_mdt_cno(cpfile) || |
194 | (cno < nilfs_mdt_cno(cpfile) && create))) | |
195 | return -EINVAL; | |
29619809 KS |
196 | |
197 | down_write(&NILFS_MDT(cpfile)->mi_sem); | |
198 | ||
199 | ret = nilfs_cpfile_get_header_block(cpfile, &header_bh); | |
200 | if (ret < 0) | |
201 | goto out_sem; | |
202 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, create, &cp_bh); | |
203 | if (ret < 0) | |
204 | goto out_header; | |
205 | kaddr = kmap(cp_bh->b_page); | |
206 | cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr); | |
207 | if (nilfs_checkpoint_invalid(cp)) { | |
208 | if (!create) { | |
209 | kunmap(cp_bh->b_page); | |
210 | brelse(cp_bh); | |
211 | ret = -ENOENT; | |
212 | goto out_header; | |
213 | } | |
214 | /* a newly-created checkpoint */ | |
215 | nilfs_checkpoint_clear_invalid(cp); | |
216 | if (!nilfs_cpfile_is_in_first(cpfile, cno)) | |
217 | nilfs_cpfile_block_add_valid_checkpoints(cpfile, cp_bh, | |
218 | kaddr, 1); | |
5fc7b141 | 219 | mark_buffer_dirty(cp_bh); |
29619809 | 220 | |
7b9c0976 | 221 | kaddr = kmap_atomic(header_bh->b_page); |
29619809 KS |
222 | header = nilfs_cpfile_block_get_header(cpfile, header_bh, |
223 | kaddr); | |
224 | le64_add_cpu(&header->ch_ncheckpoints, 1); | |
7b9c0976 | 225 | kunmap_atomic(kaddr); |
5fc7b141 | 226 | mark_buffer_dirty(header_bh); |
29619809 KS |
227 | nilfs_mdt_mark_dirty(cpfile); |
228 | } | |
229 | ||
230 | if (cpp != NULL) | |
231 | *cpp = cp; | |
232 | *bhp = cp_bh; | |
233 | ||
234 | out_header: | |
235 | brelse(header_bh); | |
236 | ||
237 | out_sem: | |
238 | up_write(&NILFS_MDT(cpfile)->mi_sem); | |
239 | return ret; | |
240 | } | |
241 | ||
242 | /** | |
243 | * nilfs_cpfile_put_checkpoint - put a checkpoint | |
244 | * @cpfile: inode of checkpoint file | |
245 | * @cno: checkpoint number | |
246 | * @bh: buffer head | |
247 | * | |
248 | * Description: nilfs_cpfile_put_checkpoint() releases the checkpoint | |
249 | * specified by @cno. @bh must be the buffer head which has been returned by | |
250 | * a previous call to nilfs_cpfile_get_checkpoint() with @cno. | |
251 | */ | |
252 | void nilfs_cpfile_put_checkpoint(struct inode *cpfile, __u64 cno, | |
253 | struct buffer_head *bh) | |
254 | { | |
255 | kunmap(bh->b_page); | |
256 | brelse(bh); | |
257 | } | |
258 | ||
259 | /** | |
260 | * nilfs_cpfile_delete_checkpoints - delete checkpoints | |
261 | * @cpfile: inode of checkpoint file | |
262 | * @start: start checkpoint number | |
263 | * @end: end checkpoint numer | |
264 | * | |
265 | * Description: nilfs_cpfile_delete_checkpoints() deletes the checkpoints in | |
266 | * the period from @start to @end, excluding @end itself. The checkpoints | |
267 | * which have been already deleted are ignored. | |
268 | * | |
269 | * Return Value: On success, 0 is returned. On error, one of the following | |
270 | * negative error codes is returned. | |
271 | * | |
272 | * %-EIO - I/O error. | |
273 | * | |
274 | * %-ENOMEM - Insufficient amount of memory available. | |
275 | * | |
276 | * %-EINVAL - invalid checkpoints. | |
277 | */ | |
278 | int nilfs_cpfile_delete_checkpoints(struct inode *cpfile, | |
279 | __u64 start, | |
280 | __u64 end) | |
281 | { | |
282 | struct buffer_head *header_bh, *cp_bh; | |
283 | struct nilfs_cpfile_header *header; | |
284 | struct nilfs_checkpoint *cp; | |
285 | size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size; | |
286 | __u64 cno; | |
287 | void *kaddr; | |
288 | unsigned long tnicps; | |
fe0627e7 | 289 | int ret, ncps, nicps, nss, count, i; |
29619809 | 290 | |
1f5abe7e RK |
291 | if (unlikely(start == 0 || start > end)) { |
292 | printk(KERN_ERR "%s: invalid range of checkpoint numbers: " | |
293 | "[%llu, %llu)\n", __func__, | |
294 | (unsigned long long)start, (unsigned long long)end); | |
295 | return -EINVAL; | |
29619809 KS |
296 | } |
297 | ||
29619809 KS |
298 | down_write(&NILFS_MDT(cpfile)->mi_sem); |
299 | ||
300 | ret = nilfs_cpfile_get_header_block(cpfile, &header_bh); | |
301 | if (ret < 0) | |
302 | goto out_sem; | |
303 | tnicps = 0; | |
fe0627e7 | 304 | nss = 0; |
29619809 KS |
305 | |
306 | for (cno = start; cno < end; cno += ncps) { | |
307 | ncps = nilfs_cpfile_checkpoints_in_block(cpfile, cno, end); | |
308 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh); | |
309 | if (ret < 0) { | |
310 | if (ret != -ENOENT) | |
d9a0a345 | 311 | break; |
29619809 KS |
312 | /* skip hole */ |
313 | ret = 0; | |
314 | continue; | |
315 | } | |
316 | ||
7b9c0976 | 317 | kaddr = kmap_atomic(cp_bh->b_page); |
29619809 KS |
318 | cp = nilfs_cpfile_block_get_checkpoint( |
319 | cpfile, cno, cp_bh, kaddr); | |
320 | nicps = 0; | |
321 | for (i = 0; i < ncps; i++, cp = (void *)cp + cpsz) { | |
fe0627e7 RK |
322 | if (nilfs_checkpoint_snapshot(cp)) { |
323 | nss++; | |
324 | } else if (!nilfs_checkpoint_invalid(cp)) { | |
29619809 KS |
325 | nilfs_checkpoint_set_invalid(cp); |
326 | nicps++; | |
327 | } | |
328 | } | |
329 | if (nicps > 0) { | |
330 | tnicps += nicps; | |
5fc7b141 | 331 | mark_buffer_dirty(cp_bh); |
29619809 | 332 | nilfs_mdt_mark_dirty(cpfile); |
5ee58148 JS |
333 | if (!nilfs_cpfile_is_in_first(cpfile, cno)) { |
334 | count = | |
335 | nilfs_cpfile_block_sub_valid_checkpoints( | |
336 | cpfile, cp_bh, kaddr, nicps); | |
337 | if (count == 0) { | |
338 | /* make hole */ | |
7b9c0976 | 339 | kunmap_atomic(kaddr); |
5ee58148 JS |
340 | brelse(cp_bh); |
341 | ret = | |
342 | nilfs_cpfile_delete_checkpoint_block( | |
343 | cpfile, cno); | |
344 | if (ret == 0) | |
345 | continue; | |
346 | printk(KERN_ERR | |
347 | "%s: cannot delete block\n", | |
348 | __func__); | |
349 | break; | |
350 | } | |
29619809 KS |
351 | } |
352 | } | |
353 | ||
7b9c0976 | 354 | kunmap_atomic(kaddr); |
29619809 KS |
355 | brelse(cp_bh); |
356 | } | |
357 | ||
358 | if (tnicps > 0) { | |
7b9c0976 | 359 | kaddr = kmap_atomic(header_bh->b_page); |
29619809 KS |
360 | header = nilfs_cpfile_block_get_header(cpfile, header_bh, |
361 | kaddr); | |
6c98cd4e | 362 | le64_add_cpu(&header->ch_ncheckpoints, -(u64)tnicps); |
5fc7b141 | 363 | mark_buffer_dirty(header_bh); |
29619809 | 364 | nilfs_mdt_mark_dirty(cpfile); |
7b9c0976 | 365 | kunmap_atomic(kaddr); |
29619809 | 366 | } |
62013ab5 | 367 | |
29619809 | 368 | brelse(header_bh); |
fe0627e7 RK |
369 | if (nss > 0) |
370 | ret = -EBUSY; | |
29619809 KS |
371 | |
372 | out_sem: | |
373 | up_write(&NILFS_MDT(cpfile)->mi_sem); | |
374 | return ret; | |
375 | } | |
376 | ||
377 | static void nilfs_cpfile_checkpoint_to_cpinfo(struct inode *cpfile, | |
378 | struct nilfs_checkpoint *cp, | |
379 | struct nilfs_cpinfo *ci) | |
380 | { | |
381 | ci->ci_flags = le32_to_cpu(cp->cp_flags); | |
382 | ci->ci_cno = le64_to_cpu(cp->cp_cno); | |
383 | ci->ci_create = le64_to_cpu(cp->cp_create); | |
384 | ci->ci_nblk_inc = le64_to_cpu(cp->cp_nblk_inc); | |
385 | ci->ci_inodes_count = le64_to_cpu(cp->cp_inodes_count); | |
386 | ci->ci_blocks_count = le64_to_cpu(cp->cp_blocks_count); | |
387 | ci->ci_next = le64_to_cpu(cp->cp_snapshot_list.ssl_next); | |
388 | } | |
389 | ||
76068c4f | 390 | static ssize_t nilfs_cpfile_do_get_cpinfo(struct inode *cpfile, __u64 *cnop, |
003ff182 | 391 | void *buf, unsigned cisz, size_t nci) |
29619809 KS |
392 | { |
393 | struct nilfs_checkpoint *cp; | |
003ff182 | 394 | struct nilfs_cpinfo *ci = buf; |
29619809 KS |
395 | struct buffer_head *bh; |
396 | size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size; | |
76068c4f | 397 | __u64 cur_cno = nilfs_mdt_cno(cpfile), cno = *cnop; |
29619809 KS |
398 | void *kaddr; |
399 | int n, ret; | |
400 | int ncps, i; | |
401 | ||
1f5abe7e RK |
402 | if (cno == 0) |
403 | return -ENOENT; /* checkpoint number 0 is invalid */ | |
29619809 KS |
404 | down_read(&NILFS_MDT(cpfile)->mi_sem); |
405 | ||
406 | for (n = 0; cno < cur_cno && n < nci; cno += ncps) { | |
407 | ncps = nilfs_cpfile_checkpoints_in_block(cpfile, cno, cur_cno); | |
408 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &bh); | |
409 | if (ret < 0) { | |
410 | if (ret != -ENOENT) | |
411 | goto out; | |
412 | continue; /* skip hole */ | |
413 | } | |
414 | ||
7b9c0976 | 415 | kaddr = kmap_atomic(bh->b_page); |
29619809 KS |
416 | cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr); |
417 | for (i = 0; i < ncps && n < nci; i++, cp = (void *)cp + cpsz) { | |
003ff182 RK |
418 | if (!nilfs_checkpoint_invalid(cp)) { |
419 | nilfs_cpfile_checkpoint_to_cpinfo(cpfile, cp, | |
420 | ci); | |
421 | ci = (void *)ci + cisz; | |
422 | n++; | |
423 | } | |
29619809 | 424 | } |
7b9c0976 | 425 | kunmap_atomic(kaddr); |
29619809 KS |
426 | brelse(bh); |
427 | } | |
428 | ||
429 | ret = n; | |
003ff182 RK |
430 | if (n > 0) { |
431 | ci = (void *)ci - cisz; | |
432 | *cnop = ci->ci_cno + 1; | |
433 | } | |
29619809 KS |
434 | |
435 | out: | |
436 | up_read(&NILFS_MDT(cpfile)->mi_sem); | |
437 | return ret; | |
438 | } | |
439 | ||
b028fcfc | 440 | static ssize_t nilfs_cpfile_do_get_ssinfo(struct inode *cpfile, __u64 *cnop, |
003ff182 | 441 | void *buf, unsigned cisz, size_t nci) |
29619809 KS |
442 | { |
443 | struct buffer_head *bh; | |
444 | struct nilfs_cpfile_header *header; | |
445 | struct nilfs_checkpoint *cp; | |
003ff182 | 446 | struct nilfs_cpinfo *ci = buf; |
b028fcfc | 447 | __u64 curr = *cnop, next; |
29619809 KS |
448 | unsigned long curr_blkoff, next_blkoff; |
449 | void *kaddr; | |
7fa10d20 | 450 | int n = 0, ret; |
29619809 KS |
451 | |
452 | down_read(&NILFS_MDT(cpfile)->mi_sem); | |
453 | ||
b028fcfc | 454 | if (curr == 0) { |
29619809 KS |
455 | ret = nilfs_cpfile_get_header_block(cpfile, &bh); |
456 | if (ret < 0) | |
457 | goto out; | |
7b9c0976 | 458 | kaddr = kmap_atomic(bh->b_page); |
29619809 KS |
459 | header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr); |
460 | curr = le64_to_cpu(header->ch_snapshot_list.ssl_next); | |
7b9c0976 | 461 | kunmap_atomic(kaddr); |
29619809 KS |
462 | brelse(bh); |
463 | if (curr == 0) { | |
464 | ret = 0; | |
465 | goto out; | |
466 | } | |
b028fcfc RK |
467 | } else if (unlikely(curr == ~(__u64)0)) { |
468 | ret = 0; | |
469 | goto out; | |
470 | } | |
471 | ||
29619809 KS |
472 | curr_blkoff = nilfs_cpfile_get_blkoff(cpfile, curr); |
473 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, curr, 0, &bh); | |
7fa10d20 RK |
474 | if (unlikely(ret < 0)) { |
475 | if (ret == -ENOENT) | |
476 | ret = 0; /* No snapshots (started from a hole block) */ | |
29619809 | 477 | goto out; |
7fa10d20 | 478 | } |
7b9c0976 | 479 | kaddr = kmap_atomic(bh->b_page); |
7fa10d20 RK |
480 | while (n < nci) { |
481 | cp = nilfs_cpfile_block_get_checkpoint(cpfile, curr, bh, kaddr); | |
482 | curr = ~(__u64)0; /* Terminator */ | |
483 | if (unlikely(nilfs_checkpoint_invalid(cp) || | |
484 | !nilfs_checkpoint_snapshot(cp))) | |
29619809 | 485 | break; |
003ff182 RK |
486 | nilfs_cpfile_checkpoint_to_cpinfo(cpfile, cp, ci); |
487 | ci = (void *)ci + cisz; | |
488 | n++; | |
7fa10d20 RK |
489 | next = le64_to_cpu(cp->cp_snapshot_list.ssl_next); |
490 | if (next == 0) | |
491 | break; /* reach end of the snapshot list */ | |
492 | ||
29619809 KS |
493 | next_blkoff = nilfs_cpfile_get_blkoff(cpfile, next); |
494 | if (curr_blkoff != next_blkoff) { | |
7b9c0976 | 495 | kunmap_atomic(kaddr); |
29619809 KS |
496 | brelse(bh); |
497 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, next, | |
498 | 0, &bh); | |
7fa10d20 RK |
499 | if (unlikely(ret < 0)) { |
500 | WARN_ON(ret == -ENOENT); | |
29619809 | 501 | goto out; |
7fa10d20 | 502 | } |
7b9c0976 | 503 | kaddr = kmap_atomic(bh->b_page); |
29619809 KS |
504 | } |
505 | curr = next; | |
506 | curr_blkoff = next_blkoff; | |
507 | } | |
7b9c0976 | 508 | kunmap_atomic(kaddr); |
29619809 | 509 | brelse(bh); |
b028fcfc | 510 | *cnop = curr; |
29619809 KS |
511 | ret = n; |
512 | ||
513 | out: | |
514 | up_read(&NILFS_MDT(cpfile)->mi_sem); | |
515 | return ret; | |
516 | } | |
517 | ||
518 | /** | |
519 | * nilfs_cpfile_get_cpinfo - | |
520 | * @cpfile: | |
521 | * @cno: | |
522 | * @ci: | |
523 | * @nci: | |
524 | */ | |
b028fcfc RK |
525 | |
526 | ssize_t nilfs_cpfile_get_cpinfo(struct inode *cpfile, __u64 *cnop, int mode, | |
003ff182 | 527 | void *buf, unsigned cisz, size_t nci) |
29619809 KS |
528 | { |
529 | switch (mode) { | |
530 | case NILFS_CHECKPOINT: | |
003ff182 | 531 | return nilfs_cpfile_do_get_cpinfo(cpfile, cnop, buf, cisz, nci); |
29619809 | 532 | case NILFS_SNAPSHOT: |
003ff182 | 533 | return nilfs_cpfile_do_get_ssinfo(cpfile, cnop, buf, cisz, nci); |
29619809 KS |
534 | default: |
535 | return -EINVAL; | |
536 | } | |
537 | } | |
538 | ||
539 | /** | |
540 | * nilfs_cpfile_delete_checkpoint - | |
541 | * @cpfile: | |
542 | * @cno: | |
543 | */ | |
544 | int nilfs_cpfile_delete_checkpoint(struct inode *cpfile, __u64 cno) | |
545 | { | |
546 | struct nilfs_cpinfo ci; | |
76068c4f | 547 | __u64 tcno = cno; |
29619809 | 548 | ssize_t nci; |
29619809 | 549 | |
003ff182 | 550 | nci = nilfs_cpfile_do_get_cpinfo(cpfile, &tcno, &ci, sizeof(ci), 1); |
29619809 KS |
551 | if (nci < 0) |
552 | return nci; | |
553 | else if (nci == 0 || ci.ci_cno != cno) | |
554 | return -ENOENT; | |
30c25be7 RK |
555 | else if (nilfs_cpinfo_snapshot(&ci)) |
556 | return -EBUSY; | |
29619809 KS |
557 | |
558 | return nilfs_cpfile_delete_checkpoints(cpfile, cno, cno + 1); | |
559 | } | |
560 | ||
561 | static struct nilfs_snapshot_list * | |
562 | nilfs_cpfile_block_get_snapshot_list(const struct inode *cpfile, | |
563 | __u64 cno, | |
564 | struct buffer_head *bh, | |
565 | void *kaddr) | |
566 | { | |
567 | struct nilfs_cpfile_header *header; | |
568 | struct nilfs_checkpoint *cp; | |
569 | struct nilfs_snapshot_list *list; | |
570 | ||
571 | if (cno != 0) { | |
572 | cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr); | |
573 | list = &cp->cp_snapshot_list; | |
574 | } else { | |
575 | header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr); | |
576 | list = &header->ch_snapshot_list; | |
577 | } | |
578 | return list; | |
579 | } | |
580 | ||
581 | static int nilfs_cpfile_set_snapshot(struct inode *cpfile, __u64 cno) | |
582 | { | |
583 | struct buffer_head *header_bh, *curr_bh, *prev_bh, *cp_bh; | |
584 | struct nilfs_cpfile_header *header; | |
585 | struct nilfs_checkpoint *cp; | |
586 | struct nilfs_snapshot_list *list; | |
587 | __u64 curr, prev; | |
588 | unsigned long curr_blkoff, prev_blkoff; | |
589 | void *kaddr; | |
590 | int ret; | |
591 | ||
1f5abe7e RK |
592 | if (cno == 0) |
593 | return -ENOENT; /* checkpoint number 0 is invalid */ | |
29619809 KS |
594 | down_write(&NILFS_MDT(cpfile)->mi_sem); |
595 | ||
596 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh); | |
597 | if (ret < 0) | |
598 | goto out_sem; | |
7b9c0976 | 599 | kaddr = kmap_atomic(cp_bh->b_page); |
29619809 KS |
600 | cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr); |
601 | if (nilfs_checkpoint_invalid(cp)) { | |
602 | ret = -ENOENT; | |
7b9c0976 | 603 | kunmap_atomic(kaddr); |
29619809 KS |
604 | goto out_cp; |
605 | } | |
606 | if (nilfs_checkpoint_snapshot(cp)) { | |
607 | ret = 0; | |
7b9c0976 | 608 | kunmap_atomic(kaddr); |
29619809 KS |
609 | goto out_cp; |
610 | } | |
7b9c0976 | 611 | kunmap_atomic(kaddr); |
29619809 KS |
612 | |
613 | ret = nilfs_cpfile_get_header_block(cpfile, &header_bh); | |
614 | if (ret < 0) | |
615 | goto out_cp; | |
7b9c0976 | 616 | kaddr = kmap_atomic(header_bh->b_page); |
29619809 KS |
617 | header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr); |
618 | list = &header->ch_snapshot_list; | |
619 | curr_bh = header_bh; | |
620 | get_bh(curr_bh); | |
621 | curr = 0; | |
622 | curr_blkoff = 0; | |
623 | prev = le64_to_cpu(list->ssl_prev); | |
624 | while (prev > cno) { | |
625 | prev_blkoff = nilfs_cpfile_get_blkoff(cpfile, prev); | |
626 | curr = prev; | |
627 | if (curr_blkoff != prev_blkoff) { | |
7b9c0976 | 628 | kunmap_atomic(kaddr); |
29619809 KS |
629 | brelse(curr_bh); |
630 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, curr, | |
631 | 0, &curr_bh); | |
632 | if (ret < 0) | |
633 | goto out_header; | |
7b9c0976 | 634 | kaddr = kmap_atomic(curr_bh->b_page); |
29619809 KS |
635 | } |
636 | curr_blkoff = prev_blkoff; | |
637 | cp = nilfs_cpfile_block_get_checkpoint( | |
638 | cpfile, curr, curr_bh, kaddr); | |
639 | list = &cp->cp_snapshot_list; | |
640 | prev = le64_to_cpu(list->ssl_prev); | |
641 | } | |
7b9c0976 | 642 | kunmap_atomic(kaddr); |
29619809 KS |
643 | |
644 | if (prev != 0) { | |
645 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0, | |
646 | &prev_bh); | |
647 | if (ret < 0) | |
648 | goto out_curr; | |
649 | } else { | |
650 | prev_bh = header_bh; | |
651 | get_bh(prev_bh); | |
652 | } | |
653 | ||
7b9c0976 | 654 | kaddr = kmap_atomic(curr_bh->b_page); |
29619809 KS |
655 | list = nilfs_cpfile_block_get_snapshot_list( |
656 | cpfile, curr, curr_bh, kaddr); | |
657 | list->ssl_prev = cpu_to_le64(cno); | |
7b9c0976 | 658 | kunmap_atomic(kaddr); |
29619809 | 659 | |
7b9c0976 | 660 | kaddr = kmap_atomic(cp_bh->b_page); |
29619809 KS |
661 | cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr); |
662 | cp->cp_snapshot_list.ssl_next = cpu_to_le64(curr); | |
663 | cp->cp_snapshot_list.ssl_prev = cpu_to_le64(prev); | |
664 | nilfs_checkpoint_set_snapshot(cp); | |
7b9c0976 | 665 | kunmap_atomic(kaddr); |
29619809 | 666 | |
7b9c0976 | 667 | kaddr = kmap_atomic(prev_bh->b_page); |
29619809 KS |
668 | list = nilfs_cpfile_block_get_snapshot_list( |
669 | cpfile, prev, prev_bh, kaddr); | |
670 | list->ssl_next = cpu_to_le64(cno); | |
7b9c0976 | 671 | kunmap_atomic(kaddr); |
29619809 | 672 | |
7b9c0976 | 673 | kaddr = kmap_atomic(header_bh->b_page); |
29619809 KS |
674 | header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr); |
675 | le64_add_cpu(&header->ch_nsnapshots, 1); | |
7b9c0976 | 676 | kunmap_atomic(kaddr); |
29619809 | 677 | |
5fc7b141 RK |
678 | mark_buffer_dirty(prev_bh); |
679 | mark_buffer_dirty(curr_bh); | |
680 | mark_buffer_dirty(cp_bh); | |
681 | mark_buffer_dirty(header_bh); | |
29619809 KS |
682 | nilfs_mdt_mark_dirty(cpfile); |
683 | ||
684 | brelse(prev_bh); | |
685 | ||
686 | out_curr: | |
687 | brelse(curr_bh); | |
688 | ||
689 | out_header: | |
690 | brelse(header_bh); | |
691 | ||
692 | out_cp: | |
693 | brelse(cp_bh); | |
694 | ||
695 | out_sem: | |
696 | up_write(&NILFS_MDT(cpfile)->mi_sem); | |
697 | return ret; | |
698 | } | |
699 | ||
700 | static int nilfs_cpfile_clear_snapshot(struct inode *cpfile, __u64 cno) | |
701 | { | |
702 | struct buffer_head *header_bh, *next_bh, *prev_bh, *cp_bh; | |
703 | struct nilfs_cpfile_header *header; | |
704 | struct nilfs_checkpoint *cp; | |
705 | struct nilfs_snapshot_list *list; | |
706 | __u64 next, prev; | |
707 | void *kaddr; | |
708 | int ret; | |
709 | ||
1f5abe7e RK |
710 | if (cno == 0) |
711 | return -ENOENT; /* checkpoint number 0 is invalid */ | |
29619809 KS |
712 | down_write(&NILFS_MDT(cpfile)->mi_sem); |
713 | ||
714 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh); | |
715 | if (ret < 0) | |
716 | goto out_sem; | |
7b9c0976 | 717 | kaddr = kmap_atomic(cp_bh->b_page); |
29619809 KS |
718 | cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr); |
719 | if (nilfs_checkpoint_invalid(cp)) { | |
720 | ret = -ENOENT; | |
7b9c0976 | 721 | kunmap_atomic(kaddr); |
29619809 KS |
722 | goto out_cp; |
723 | } | |
724 | if (!nilfs_checkpoint_snapshot(cp)) { | |
725 | ret = 0; | |
7b9c0976 | 726 | kunmap_atomic(kaddr); |
29619809 KS |
727 | goto out_cp; |
728 | } | |
729 | ||
730 | list = &cp->cp_snapshot_list; | |
731 | next = le64_to_cpu(list->ssl_next); | |
732 | prev = le64_to_cpu(list->ssl_prev); | |
7b9c0976 | 733 | kunmap_atomic(kaddr); |
29619809 KS |
734 | |
735 | ret = nilfs_cpfile_get_header_block(cpfile, &header_bh); | |
736 | if (ret < 0) | |
737 | goto out_cp; | |
738 | if (next != 0) { | |
739 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, next, 0, | |
740 | &next_bh); | |
741 | if (ret < 0) | |
742 | goto out_header; | |
743 | } else { | |
744 | next_bh = header_bh; | |
745 | get_bh(next_bh); | |
746 | } | |
747 | if (prev != 0) { | |
748 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0, | |
749 | &prev_bh); | |
750 | if (ret < 0) | |
751 | goto out_next; | |
752 | } else { | |
753 | prev_bh = header_bh; | |
754 | get_bh(prev_bh); | |
755 | } | |
756 | ||
7b9c0976 | 757 | kaddr = kmap_atomic(next_bh->b_page); |
29619809 KS |
758 | list = nilfs_cpfile_block_get_snapshot_list( |
759 | cpfile, next, next_bh, kaddr); | |
760 | list->ssl_prev = cpu_to_le64(prev); | |
7b9c0976 | 761 | kunmap_atomic(kaddr); |
29619809 | 762 | |
7b9c0976 | 763 | kaddr = kmap_atomic(prev_bh->b_page); |
29619809 KS |
764 | list = nilfs_cpfile_block_get_snapshot_list( |
765 | cpfile, prev, prev_bh, kaddr); | |
766 | list->ssl_next = cpu_to_le64(next); | |
7b9c0976 | 767 | kunmap_atomic(kaddr); |
29619809 | 768 | |
7b9c0976 | 769 | kaddr = kmap_atomic(cp_bh->b_page); |
29619809 KS |
770 | cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr); |
771 | cp->cp_snapshot_list.ssl_next = cpu_to_le64(0); | |
772 | cp->cp_snapshot_list.ssl_prev = cpu_to_le64(0); | |
773 | nilfs_checkpoint_clear_snapshot(cp); | |
7b9c0976 | 774 | kunmap_atomic(kaddr); |
29619809 | 775 | |
7b9c0976 | 776 | kaddr = kmap_atomic(header_bh->b_page); |
29619809 KS |
777 | header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr); |
778 | le64_add_cpu(&header->ch_nsnapshots, -1); | |
7b9c0976 | 779 | kunmap_atomic(kaddr); |
29619809 | 780 | |
5fc7b141 RK |
781 | mark_buffer_dirty(next_bh); |
782 | mark_buffer_dirty(prev_bh); | |
783 | mark_buffer_dirty(cp_bh); | |
784 | mark_buffer_dirty(header_bh); | |
29619809 KS |
785 | nilfs_mdt_mark_dirty(cpfile); |
786 | ||
787 | brelse(prev_bh); | |
788 | ||
789 | out_next: | |
790 | brelse(next_bh); | |
791 | ||
792 | out_header: | |
793 | brelse(header_bh); | |
794 | ||
795 | out_cp: | |
796 | brelse(cp_bh); | |
797 | ||
798 | out_sem: | |
799 | up_write(&NILFS_MDT(cpfile)->mi_sem); | |
800 | return ret; | |
801 | } | |
802 | ||
803 | /** | |
804 | * nilfs_cpfile_is_snapshot - | |
805 | * @cpfile: inode of checkpoint file | |
806 | * @cno: checkpoint number | |
807 | * | |
808 | * Description: | |
809 | * | |
810 | * Return Value: On success, 1 is returned if the checkpoint specified by | |
811 | * @cno is a snapshot, or 0 if not. On error, one of the following negative | |
812 | * error codes is returned. | |
813 | * | |
814 | * %-EIO - I/O error. | |
815 | * | |
816 | * %-ENOMEM - Insufficient amount of memory available. | |
817 | * | |
818 | * %-ENOENT - No such checkpoint. | |
819 | */ | |
820 | int nilfs_cpfile_is_snapshot(struct inode *cpfile, __u64 cno) | |
821 | { | |
822 | struct buffer_head *bh; | |
823 | struct nilfs_checkpoint *cp; | |
824 | void *kaddr; | |
825 | int ret; | |
826 | ||
43be0ec0 ZY |
827 | /* CP number is invalid if it's zero or larger than the |
828 | largest exist one.*/ | |
829 | if (cno == 0 || cno >= nilfs_mdt_cno(cpfile)) | |
830 | return -ENOENT; | |
29619809 KS |
831 | down_read(&NILFS_MDT(cpfile)->mi_sem); |
832 | ||
833 | ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &bh); | |
834 | if (ret < 0) | |
835 | goto out; | |
7b9c0976 | 836 | kaddr = kmap_atomic(bh->b_page); |
29619809 | 837 | cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr); |
43be0ec0 ZY |
838 | if (nilfs_checkpoint_invalid(cp)) |
839 | ret = -ENOENT; | |
840 | else | |
841 | ret = nilfs_checkpoint_snapshot(cp); | |
7b9c0976 | 842 | kunmap_atomic(kaddr); |
29619809 KS |
843 | brelse(bh); |
844 | ||
845 | out: | |
846 | up_read(&NILFS_MDT(cpfile)->mi_sem); | |
847 | return ret; | |
848 | } | |
849 | ||
850 | /** | |
851 | * nilfs_cpfile_change_cpmode - change checkpoint mode | |
852 | * @cpfile: inode of checkpoint file | |
853 | * @cno: checkpoint number | |
854 | * @status: mode of checkpoint | |
855 | * | |
856 | * Description: nilfs_change_cpmode() changes the mode of the checkpoint | |
857 | * specified by @cno. The mode @mode is NILFS_CHECKPOINT or NILFS_SNAPSHOT. | |
858 | * | |
859 | * Return Value: On success, 0 is returned. On error, one of the following | |
860 | * negative error codes is returned. | |
861 | * | |
862 | * %-EIO - I/O error. | |
863 | * | |
864 | * %-ENOMEM - Insufficient amount of memory available. | |
865 | * | |
866 | * %-ENOENT - No such checkpoint. | |
867 | */ | |
868 | int nilfs_cpfile_change_cpmode(struct inode *cpfile, __u64 cno, int mode) | |
869 | { | |
29619809 KS |
870 | int ret; |
871 | ||
29619809 KS |
872 | switch (mode) { |
873 | case NILFS_CHECKPOINT: | |
032dbb3b RK |
874 | if (nilfs_checkpoint_is_mounted(cpfile->i_sb, cno)) |
875 | /* | |
876 | * Current implementation does not have to protect | |
877 | * plain read-only mounts since they are exclusive | |
878 | * with a read/write mount and are protected from the | |
879 | * cleaner. | |
880 | */ | |
29619809 | 881 | ret = -EBUSY; |
032dbb3b | 882 | else |
29619809 | 883 | ret = nilfs_cpfile_clear_snapshot(cpfile, cno); |
29619809 KS |
884 | return ret; |
885 | case NILFS_SNAPSHOT: | |
886 | return nilfs_cpfile_set_snapshot(cpfile, cno); | |
887 | default: | |
888 | return -EINVAL; | |
889 | } | |
890 | } | |
891 | ||
892 | /** | |
893 | * nilfs_cpfile_get_stat - get checkpoint statistics | |
894 | * @cpfile: inode of checkpoint file | |
895 | * @stat: pointer to a structure of checkpoint statistics | |
896 | * | |
897 | * Description: nilfs_cpfile_get_stat() returns information about checkpoints. | |
898 | * | |
899 | * Return Value: On success, 0 is returned, and checkpoints information is | |
900 | * stored in the place pointed by @stat. On error, one of the following | |
901 | * negative error codes is returned. | |
902 | * | |
903 | * %-EIO - I/O error. | |
904 | * | |
905 | * %-ENOMEM - Insufficient amount of memory available. | |
906 | */ | |
907 | int nilfs_cpfile_get_stat(struct inode *cpfile, struct nilfs_cpstat *cpstat) | |
908 | { | |
909 | struct buffer_head *bh; | |
910 | struct nilfs_cpfile_header *header; | |
911 | void *kaddr; | |
912 | int ret; | |
913 | ||
914 | down_read(&NILFS_MDT(cpfile)->mi_sem); | |
915 | ||
916 | ret = nilfs_cpfile_get_header_block(cpfile, &bh); | |
917 | if (ret < 0) | |
918 | goto out_sem; | |
7b9c0976 | 919 | kaddr = kmap_atomic(bh->b_page); |
29619809 KS |
920 | header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr); |
921 | cpstat->cs_cno = nilfs_mdt_cno(cpfile); | |
922 | cpstat->cs_ncps = le64_to_cpu(header->ch_ncheckpoints); | |
923 | cpstat->cs_nsss = le64_to_cpu(header->ch_nsnapshots); | |
7b9c0976 | 924 | kunmap_atomic(kaddr); |
29619809 KS |
925 | brelse(bh); |
926 | ||
927 | out_sem: | |
928 | up_read(&NILFS_MDT(cpfile)->mi_sem); | |
929 | return ret; | |
930 | } | |
79739565 | 931 | |
8707df38 | 932 | /** |
f1e89c86 RK |
933 | * nilfs_cpfile_read - read or get cpfile inode |
934 | * @sb: super block instance | |
79739565 | 935 | * @cpsize: size of a checkpoint entry |
f1e89c86 RK |
936 | * @raw_inode: on-disk cpfile inode |
937 | * @inodep: buffer to store the inode | |
79739565 | 938 | */ |
f1e89c86 RK |
939 | int nilfs_cpfile_read(struct super_block *sb, size_t cpsize, |
940 | struct nilfs_inode *raw_inode, struct inode **inodep) | |
79739565 RK |
941 | { |
942 | struct inode *cpfile; | |
f1e89c86 | 943 | int err; |
79739565 | 944 | |
0ec060d1 RK |
945 | if (cpsize > sb->s_blocksize) { |
946 | printk(KERN_ERR | |
947 | "NILFS: too large checkpoint size: %zu bytes.\n", | |
948 | cpsize); | |
949 | return -EINVAL; | |
950 | } else if (cpsize < NILFS_MIN_CHECKPOINT_SIZE) { | |
951 | printk(KERN_ERR | |
952 | "NILFS: too small checkpoint size: %zu bytes.\n", | |
953 | cpsize); | |
954 | return -EINVAL; | |
955 | } | |
956 | ||
f1e89c86 RK |
957 | cpfile = nilfs_iget_locked(sb, NULL, NILFS_CPFILE_INO); |
958 | if (unlikely(!cpfile)) | |
959 | return -ENOMEM; | |
960 | if (!(cpfile->i_state & I_NEW)) | |
961 | goto out; | |
962 | ||
963 | err = nilfs_mdt_init(cpfile, NILFS_MDT_GFP, 0); | |
964 | if (err) | |
965 | goto failed; | |
966 | ||
967 | nilfs_mdt_set_entry_size(cpfile, cpsize, | |
968 | sizeof(struct nilfs_cpfile_header)); | |
969 | ||
970 | err = nilfs_read_inode_common(cpfile, raw_inode); | |
971 | if (err) | |
972 | goto failed; | |
973 | ||
974 | unlock_new_inode(cpfile); | |
975 | out: | |
976 | *inodep = cpfile; | |
977 | return 0; | |
978 | failed: | |
979 | iget_failed(cpfile); | |
980 | return err; | |
79739565 | 981 | } |