blob: b6596cab9e99e4a2e680b54750b9da09e8946c86 [file] [log] [blame]
Koji Sato29619802009-04-06 19:01:31 -07001/*
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
33static inline unsigned long
34nilfs_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 */
40static unsigned long
41nilfs_cpfile_get_blkoff(const struct inode *cpfile, __u64 cno)
42{
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -070043 __u64 tcno = cno + NILFS_MDT(cpfile)->mi_first_entry_offset - 1;
Koji Sato29619802009-04-06 19:01:31 -070044 do_div(tcno, nilfs_cpfile_checkpoints_per_block(cpfile));
45 return (unsigned long)tcno;
46}
47
48/* offset in block */
49static unsigned long
50nilfs_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
Ryusuke Konishi53a2c3b2015-04-16 12:46:42 -070056static __u64 nilfs_cpfile_first_checkpoint_in_block(const struct inode *cpfile,
57 unsigned long blkoff)
58{
59 return (__u64)nilfs_cpfile_checkpoints_per_block(cpfile) * blkoff
60 + 1 - NILFS_MDT(cpfile)->mi_first_entry_offset;
61}
62
Koji Sato29619802009-04-06 19:01:31 -070063static unsigned long
64nilfs_cpfile_checkpoints_in_block(const struct inode *cpfile,
65 __u64 curr,
66 __u64 max)
67{
68 return min_t(__u64,
69 nilfs_cpfile_checkpoints_per_block(cpfile) -
70 nilfs_cpfile_get_offset(cpfile, curr),
71 max - curr);
72}
73
74static inline int nilfs_cpfile_is_in_first(const struct inode *cpfile,
75 __u64 cno)
76{
77 return nilfs_cpfile_get_blkoff(cpfile, cno) == 0;
78}
79
80static unsigned int
81nilfs_cpfile_block_add_valid_checkpoints(const struct inode *cpfile,
82 struct buffer_head *bh,
83 void *kaddr,
84 unsigned int n)
85{
86 struct nilfs_checkpoint *cp = kaddr + bh_offset(bh);
87 unsigned int count;
88
89 count = le32_to_cpu(cp->cp_checkpoints_count) + n;
90 cp->cp_checkpoints_count = cpu_to_le32(count);
91 return count;
92}
93
94static unsigned int
95nilfs_cpfile_block_sub_valid_checkpoints(const struct inode *cpfile,
96 struct buffer_head *bh,
97 void *kaddr,
98 unsigned int n)
99{
100 struct nilfs_checkpoint *cp = kaddr + bh_offset(bh);
101 unsigned int count;
102
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700103 WARN_ON(le32_to_cpu(cp->cp_checkpoints_count) < n);
Koji Sato29619802009-04-06 19:01:31 -0700104 count = le32_to_cpu(cp->cp_checkpoints_count) - n;
105 cp->cp_checkpoints_count = cpu_to_le32(count);
106 return count;
107}
108
109static inline struct nilfs_cpfile_header *
110nilfs_cpfile_block_get_header(const struct inode *cpfile,
111 struct buffer_head *bh,
112 void *kaddr)
113{
114 return kaddr + bh_offset(bh);
115}
116
117static struct nilfs_checkpoint *
118nilfs_cpfile_block_get_checkpoint(const struct inode *cpfile, __u64 cno,
119 struct buffer_head *bh,
120 void *kaddr)
121{
122 return kaddr + bh_offset(bh) + nilfs_cpfile_get_offset(cpfile, cno) *
123 NILFS_MDT(cpfile)->mi_entry_size;
124}
125
126static void nilfs_cpfile_block_init(struct inode *cpfile,
127 struct buffer_head *bh,
128 void *kaddr)
129{
130 struct nilfs_checkpoint *cp = kaddr + bh_offset(bh);
131 size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size;
132 int n = nilfs_cpfile_checkpoints_per_block(cpfile);
133
134 while (n-- > 0) {
135 nilfs_checkpoint_set_invalid(cp);
136 cp = (void *)cp + cpsz;
137 }
138}
139
140static inline int nilfs_cpfile_get_header_block(struct inode *cpfile,
141 struct buffer_head **bhp)
142{
143 return nilfs_mdt_get_block(cpfile, 0, 0, NULL, bhp);
144}
145
146static inline int nilfs_cpfile_get_checkpoint_block(struct inode *cpfile,
147 __u64 cno,
148 int create,
149 struct buffer_head **bhp)
150{
151 return nilfs_mdt_get_block(cpfile,
152 nilfs_cpfile_get_blkoff(cpfile, cno),
153 create, nilfs_cpfile_block_init, bhp);
154}
155
Ryusuke Konishi53a2c3b2015-04-16 12:46:42 -0700156/**
157 * nilfs_cpfile_find_checkpoint_block - find and get a buffer on cpfile
158 * @cpfile: inode of cpfile
159 * @start_cno: start checkpoint number (inclusive)
160 * @end_cno: end checkpoint number (inclusive)
161 * @cnop: place to store the next checkpoint number
162 * @bhp: place to store a pointer to buffer_head struct
163 *
164 * Return Value: On success, it returns 0. On error, the following negative
165 * error code is returned.
166 *
167 * %-ENOMEM - Insufficient memory available.
168 *
169 * %-EIO - I/O error
170 *
171 * %-ENOENT - no block exists in the range.
172 */
173static int nilfs_cpfile_find_checkpoint_block(struct inode *cpfile,
174 __u64 start_cno, __u64 end_cno,
175 __u64 *cnop,
176 struct buffer_head **bhp)
177{
178 unsigned long start, end, blkoff;
179 int ret;
180
181 if (unlikely(start_cno > end_cno))
182 return -ENOENT;
183
184 start = nilfs_cpfile_get_blkoff(cpfile, start_cno);
185 end = nilfs_cpfile_get_blkoff(cpfile, end_cno);
186
187 ret = nilfs_mdt_find_block(cpfile, start, end, &blkoff, bhp);
188 if (!ret)
189 *cnop = (blkoff == start) ? start_cno :
190 nilfs_cpfile_first_checkpoint_in_block(cpfile, blkoff);
191 return ret;
192}
193
Koji Sato29619802009-04-06 19:01:31 -0700194static inline int nilfs_cpfile_delete_checkpoint_block(struct inode *cpfile,
195 __u64 cno)
196{
197 return nilfs_mdt_delete_block(cpfile,
198 nilfs_cpfile_get_blkoff(cpfile, cno));
199}
200
201/**
202 * nilfs_cpfile_get_checkpoint - get a checkpoint
203 * @cpfile: inode of checkpoint file
204 * @cno: checkpoint number
205 * @create: create flag
206 * @cpp: pointer to a checkpoint
207 * @bhp: pointer to a buffer head
208 *
209 * Description: nilfs_cpfile_get_checkpoint() acquires the checkpoint
210 * specified by @cno. A new checkpoint will be created if @cno is the current
211 * checkpoint number and @create is nonzero.
212 *
213 * Return Value: On success, 0 is returned, and the checkpoint and the
214 * buffer head of the buffer on which the checkpoint is located are stored in
215 * the place pointed by @cpp and @bhp, respectively. On error, one of the
216 * following negative error codes is returned.
217 *
218 * %-EIO - I/O error.
219 *
220 * %-ENOMEM - Insufficient amount of memory available.
221 *
222 * %-ENOENT - No such checkpoint.
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700223 *
224 * %-EINVAL - invalid checkpoint.
Koji Sato29619802009-04-06 19:01:31 -0700225 */
226int nilfs_cpfile_get_checkpoint(struct inode *cpfile,
227 __u64 cno,
228 int create,
229 struct nilfs_checkpoint **cpp,
230 struct buffer_head **bhp)
231{
232 struct buffer_head *header_bh, *cp_bh;
233 struct nilfs_cpfile_header *header;
234 struct nilfs_checkpoint *cp;
235 void *kaddr;
236 int ret;
237
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700238 if (unlikely(cno < 1 || cno > nilfs_mdt_cno(cpfile) ||
239 (cno < nilfs_mdt_cno(cpfile) && create)))
240 return -EINVAL;
Koji Sato29619802009-04-06 19:01:31 -0700241
242 down_write(&NILFS_MDT(cpfile)->mi_sem);
243
244 ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
245 if (ret < 0)
246 goto out_sem;
247 ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, create, &cp_bh);
248 if (ret < 0)
249 goto out_header;
250 kaddr = kmap(cp_bh->b_page);
251 cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
252 if (nilfs_checkpoint_invalid(cp)) {
253 if (!create) {
254 kunmap(cp_bh->b_page);
255 brelse(cp_bh);
256 ret = -ENOENT;
257 goto out_header;
258 }
259 /* a newly-created checkpoint */
260 nilfs_checkpoint_clear_invalid(cp);
261 if (!nilfs_cpfile_is_in_first(cpfile, cno))
262 nilfs_cpfile_block_add_valid_checkpoints(cpfile, cp_bh,
263 kaddr, 1);
Ryusuke Konishi5fc7b142011-05-05 12:56:51 +0900264 mark_buffer_dirty(cp_bh);
Koji Sato29619802009-04-06 19:01:31 -0700265
Cong Wang7b9c0972011-11-25 23:14:33 +0800266 kaddr = kmap_atomic(header_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700267 header = nilfs_cpfile_block_get_header(cpfile, header_bh,
268 kaddr);
269 le64_add_cpu(&header->ch_ncheckpoints, 1);
Cong Wang7b9c0972011-11-25 23:14:33 +0800270 kunmap_atomic(kaddr);
Ryusuke Konishi5fc7b142011-05-05 12:56:51 +0900271 mark_buffer_dirty(header_bh);
Koji Sato29619802009-04-06 19:01:31 -0700272 nilfs_mdt_mark_dirty(cpfile);
273 }
274
275 if (cpp != NULL)
276 *cpp = cp;
277 *bhp = cp_bh;
278
279 out_header:
280 brelse(header_bh);
281
282 out_sem:
283 up_write(&NILFS_MDT(cpfile)->mi_sem);
284 return ret;
285}
286
287/**
288 * nilfs_cpfile_put_checkpoint - put a checkpoint
289 * @cpfile: inode of checkpoint file
290 * @cno: checkpoint number
291 * @bh: buffer head
292 *
293 * Description: nilfs_cpfile_put_checkpoint() releases the checkpoint
294 * specified by @cno. @bh must be the buffer head which has been returned by
295 * a previous call to nilfs_cpfile_get_checkpoint() with @cno.
296 */
297void nilfs_cpfile_put_checkpoint(struct inode *cpfile, __u64 cno,
298 struct buffer_head *bh)
299{
300 kunmap(bh->b_page);
301 brelse(bh);
302}
303
304/**
305 * nilfs_cpfile_delete_checkpoints - delete checkpoints
306 * @cpfile: inode of checkpoint file
307 * @start: start checkpoint number
308 * @end: end checkpoint numer
309 *
310 * Description: nilfs_cpfile_delete_checkpoints() deletes the checkpoints in
311 * the period from @start to @end, excluding @end itself. The checkpoints
312 * which have been already deleted are ignored.
313 *
314 * Return Value: On success, 0 is returned. On error, one of the following
315 * negative error codes is returned.
316 *
317 * %-EIO - I/O error.
318 *
319 * %-ENOMEM - Insufficient amount of memory available.
320 *
321 * %-EINVAL - invalid checkpoints.
322 */
323int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
324 __u64 start,
325 __u64 end)
326{
327 struct buffer_head *header_bh, *cp_bh;
328 struct nilfs_cpfile_header *header;
329 struct nilfs_checkpoint *cp;
330 size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size;
331 __u64 cno;
332 void *kaddr;
333 unsigned long tnicps;
Ryusuke Konishife0627e2012-07-30 14:42:05 -0700334 int ret, ncps, nicps, nss, count, i;
Koji Sato29619802009-04-06 19:01:31 -0700335
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700336 if (unlikely(start == 0 || start > end)) {
337 printk(KERN_ERR "%s: invalid range of checkpoint numbers: "
338 "[%llu, %llu)\n", __func__,
339 (unsigned long long)start, (unsigned long long)end);
340 return -EINVAL;
Koji Sato29619802009-04-06 19:01:31 -0700341 }
342
Koji Sato29619802009-04-06 19:01:31 -0700343 down_write(&NILFS_MDT(cpfile)->mi_sem);
344
345 ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
346 if (ret < 0)
347 goto out_sem;
348 tnicps = 0;
Ryusuke Konishife0627e2012-07-30 14:42:05 -0700349 nss = 0;
Koji Sato29619802009-04-06 19:01:31 -0700350
351 for (cno = start; cno < end; cno += ncps) {
352 ncps = nilfs_cpfile_checkpoints_in_block(cpfile, cno, end);
353 ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
354 if (ret < 0) {
355 if (ret != -ENOENT)
Jiro SEKIBAd9a0a342009-07-04 23:00:53 +0900356 break;
Koji Sato29619802009-04-06 19:01:31 -0700357 /* skip hole */
358 ret = 0;
359 continue;
360 }
361
Cong Wang7b9c0972011-11-25 23:14:33 +0800362 kaddr = kmap_atomic(cp_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700363 cp = nilfs_cpfile_block_get_checkpoint(
364 cpfile, cno, cp_bh, kaddr);
365 nicps = 0;
366 for (i = 0; i < ncps; i++, cp = (void *)cp + cpsz) {
Ryusuke Konishife0627e2012-07-30 14:42:05 -0700367 if (nilfs_checkpoint_snapshot(cp)) {
368 nss++;
369 } else if (!nilfs_checkpoint_invalid(cp)) {
Koji Sato29619802009-04-06 19:01:31 -0700370 nilfs_checkpoint_set_invalid(cp);
371 nicps++;
372 }
373 }
374 if (nicps > 0) {
375 tnicps += nicps;
Ryusuke Konishi5fc7b142011-05-05 12:56:51 +0900376 mark_buffer_dirty(cp_bh);
Koji Sato29619802009-04-06 19:01:31 -0700377 nilfs_mdt_mark_dirty(cpfile);
Jiro SEKIBA5ee58142009-12-06 15:43:56 +0900378 if (!nilfs_cpfile_is_in_first(cpfile, cno)) {
379 count =
380 nilfs_cpfile_block_sub_valid_checkpoints(
381 cpfile, cp_bh, kaddr, nicps);
382 if (count == 0) {
383 /* make hole */
Cong Wang7b9c0972011-11-25 23:14:33 +0800384 kunmap_atomic(kaddr);
Jiro SEKIBA5ee58142009-12-06 15:43:56 +0900385 brelse(cp_bh);
386 ret =
387 nilfs_cpfile_delete_checkpoint_block(
388 cpfile, cno);
389 if (ret == 0)
390 continue;
391 printk(KERN_ERR
392 "%s: cannot delete block\n",
393 __func__);
394 break;
395 }
Koji Sato29619802009-04-06 19:01:31 -0700396 }
397 }
398
Cong Wang7b9c0972011-11-25 23:14:33 +0800399 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700400 brelse(cp_bh);
401 }
402
403 if (tnicps > 0) {
Cong Wang7b9c0972011-11-25 23:14:33 +0800404 kaddr = kmap_atomic(header_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700405 header = nilfs_cpfile_block_get_header(cpfile, header_bh,
406 kaddr);
Koji Sato6c98cd42009-04-06 19:01:32 -0700407 le64_add_cpu(&header->ch_ncheckpoints, -(u64)tnicps);
Ryusuke Konishi5fc7b142011-05-05 12:56:51 +0900408 mark_buffer_dirty(header_bh);
Koji Sato29619802009-04-06 19:01:31 -0700409 nilfs_mdt_mark_dirty(cpfile);
Cong Wang7b9c0972011-11-25 23:14:33 +0800410 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700411 }
Ryusuke Konishi62013ab2009-05-30 21:50:58 +0900412
Koji Sato29619802009-04-06 19:01:31 -0700413 brelse(header_bh);
Ryusuke Konishife0627e2012-07-30 14:42:05 -0700414 if (nss > 0)
415 ret = -EBUSY;
Koji Sato29619802009-04-06 19:01:31 -0700416
417 out_sem:
418 up_write(&NILFS_MDT(cpfile)->mi_sem);
419 return ret;
420}
421
422static void nilfs_cpfile_checkpoint_to_cpinfo(struct inode *cpfile,
423 struct nilfs_checkpoint *cp,
424 struct nilfs_cpinfo *ci)
425{
426 ci->ci_flags = le32_to_cpu(cp->cp_flags);
427 ci->ci_cno = le64_to_cpu(cp->cp_cno);
428 ci->ci_create = le64_to_cpu(cp->cp_create);
429 ci->ci_nblk_inc = le64_to_cpu(cp->cp_nblk_inc);
430 ci->ci_inodes_count = le64_to_cpu(cp->cp_inodes_count);
431 ci->ci_blocks_count = le64_to_cpu(cp->cp_blocks_count);
432 ci->ci_next = le64_to_cpu(cp->cp_snapshot_list.ssl_next);
433}
434
Ryusuke Konishi76068c42009-04-06 19:01:50 -0700435static ssize_t nilfs_cpfile_do_get_cpinfo(struct inode *cpfile, __u64 *cnop,
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900436 void *buf, unsigned cisz, size_t nci)
Koji Sato29619802009-04-06 19:01:31 -0700437{
438 struct nilfs_checkpoint *cp;
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900439 struct nilfs_cpinfo *ci = buf;
Koji Sato29619802009-04-06 19:01:31 -0700440 struct buffer_head *bh;
441 size_t cpsz = NILFS_MDT(cpfile)->mi_entry_size;
Ryusuke Konishi76068c42009-04-06 19:01:50 -0700442 __u64 cur_cno = nilfs_mdt_cno(cpfile), cno = *cnop;
Koji Sato29619802009-04-06 19:01:31 -0700443 void *kaddr;
444 int n, ret;
445 int ncps, i;
446
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700447 if (cno == 0)
448 return -ENOENT; /* checkpoint number 0 is invalid */
Koji Sato29619802009-04-06 19:01:31 -0700449 down_read(&NILFS_MDT(cpfile)->mi_sem);
450
Ryusuke Konishi53a2c3b2015-04-16 12:46:42 -0700451 for (n = 0; n < nci; cno += ncps) {
452 ret = nilfs_cpfile_find_checkpoint_block(
453 cpfile, cno, cur_cno - 1, &cno, &bh);
Koji Sato29619802009-04-06 19:01:31 -0700454 if (ret < 0) {
Ryusuke Konishi53a2c3b2015-04-16 12:46:42 -0700455 if (likely(ret == -ENOENT))
456 break;
457 goto out;
Koji Sato29619802009-04-06 19:01:31 -0700458 }
Ryusuke Konishi53a2c3b2015-04-16 12:46:42 -0700459 ncps = nilfs_cpfile_checkpoints_in_block(cpfile, cno, cur_cno);
Koji Sato29619802009-04-06 19:01:31 -0700460
Cong Wang7b9c0972011-11-25 23:14:33 +0800461 kaddr = kmap_atomic(bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700462 cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr);
463 for (i = 0; i < ncps && n < nci; i++, cp = (void *)cp + cpsz) {
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900464 if (!nilfs_checkpoint_invalid(cp)) {
465 nilfs_cpfile_checkpoint_to_cpinfo(cpfile, cp,
466 ci);
467 ci = (void *)ci + cisz;
468 n++;
469 }
Koji Sato29619802009-04-06 19:01:31 -0700470 }
Cong Wang7b9c0972011-11-25 23:14:33 +0800471 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700472 brelse(bh);
473 }
474
475 ret = n;
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900476 if (n > 0) {
477 ci = (void *)ci - cisz;
478 *cnop = ci->ci_cno + 1;
479 }
Koji Sato29619802009-04-06 19:01:31 -0700480
481 out:
482 up_read(&NILFS_MDT(cpfile)->mi_sem);
483 return ret;
484}
485
Ryusuke Konishib028fcf2009-04-06 19:01:47 -0700486static ssize_t nilfs_cpfile_do_get_ssinfo(struct inode *cpfile, __u64 *cnop,
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900487 void *buf, unsigned cisz, size_t nci)
Koji Sato29619802009-04-06 19:01:31 -0700488{
489 struct buffer_head *bh;
490 struct nilfs_cpfile_header *header;
491 struct nilfs_checkpoint *cp;
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900492 struct nilfs_cpinfo *ci = buf;
Ryusuke Konishib028fcf2009-04-06 19:01:47 -0700493 __u64 curr = *cnop, next;
Koji Sato29619802009-04-06 19:01:31 -0700494 unsigned long curr_blkoff, next_blkoff;
495 void *kaddr;
Ryusuke Konishi7fa10d22009-04-06 19:01:48 -0700496 int n = 0, ret;
Koji Sato29619802009-04-06 19:01:31 -0700497
498 down_read(&NILFS_MDT(cpfile)->mi_sem);
499
Ryusuke Konishib028fcf2009-04-06 19:01:47 -0700500 if (curr == 0) {
Koji Sato29619802009-04-06 19:01:31 -0700501 ret = nilfs_cpfile_get_header_block(cpfile, &bh);
502 if (ret < 0)
503 goto out;
Cong Wang7b9c0972011-11-25 23:14:33 +0800504 kaddr = kmap_atomic(bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700505 header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr);
506 curr = le64_to_cpu(header->ch_snapshot_list.ssl_next);
Cong Wang7b9c0972011-11-25 23:14:33 +0800507 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700508 brelse(bh);
509 if (curr == 0) {
510 ret = 0;
511 goto out;
512 }
Ryusuke Konishib028fcf2009-04-06 19:01:47 -0700513 } else if (unlikely(curr == ~(__u64)0)) {
514 ret = 0;
515 goto out;
516 }
517
Koji Sato29619802009-04-06 19:01:31 -0700518 curr_blkoff = nilfs_cpfile_get_blkoff(cpfile, curr);
519 ret = nilfs_cpfile_get_checkpoint_block(cpfile, curr, 0, &bh);
Ryusuke Konishi7fa10d22009-04-06 19:01:48 -0700520 if (unlikely(ret < 0)) {
521 if (ret == -ENOENT)
522 ret = 0; /* No snapshots (started from a hole block) */
Koji Sato29619802009-04-06 19:01:31 -0700523 goto out;
Ryusuke Konishi7fa10d22009-04-06 19:01:48 -0700524 }
Cong Wang7b9c0972011-11-25 23:14:33 +0800525 kaddr = kmap_atomic(bh->b_page);
Ryusuke Konishi7fa10d22009-04-06 19:01:48 -0700526 while (n < nci) {
527 cp = nilfs_cpfile_block_get_checkpoint(cpfile, curr, bh, kaddr);
528 curr = ~(__u64)0; /* Terminator */
529 if (unlikely(nilfs_checkpoint_invalid(cp) ||
530 !nilfs_checkpoint_snapshot(cp)))
Koji Sato29619802009-04-06 19:01:31 -0700531 break;
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900532 nilfs_cpfile_checkpoint_to_cpinfo(cpfile, cp, ci);
533 ci = (void *)ci + cisz;
534 n++;
Ryusuke Konishi7fa10d22009-04-06 19:01:48 -0700535 next = le64_to_cpu(cp->cp_snapshot_list.ssl_next);
536 if (next == 0)
537 break; /* reach end of the snapshot list */
538
Koji Sato29619802009-04-06 19:01:31 -0700539 next_blkoff = nilfs_cpfile_get_blkoff(cpfile, next);
540 if (curr_blkoff != next_blkoff) {
Cong Wang7b9c0972011-11-25 23:14:33 +0800541 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700542 brelse(bh);
543 ret = nilfs_cpfile_get_checkpoint_block(cpfile, next,
544 0, &bh);
Ryusuke Konishi7fa10d22009-04-06 19:01:48 -0700545 if (unlikely(ret < 0)) {
546 WARN_ON(ret == -ENOENT);
Koji Sato29619802009-04-06 19:01:31 -0700547 goto out;
Ryusuke Konishi7fa10d22009-04-06 19:01:48 -0700548 }
Cong Wang7b9c0972011-11-25 23:14:33 +0800549 kaddr = kmap_atomic(bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700550 }
551 curr = next;
552 curr_blkoff = next_blkoff;
553 }
Cong Wang7b9c0972011-11-25 23:14:33 +0800554 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700555 brelse(bh);
Ryusuke Konishib028fcf2009-04-06 19:01:47 -0700556 *cnop = curr;
Koji Sato29619802009-04-06 19:01:31 -0700557 ret = n;
558
559 out:
560 up_read(&NILFS_MDT(cpfile)->mi_sem);
561 return ret;
562}
563
564/**
565 * nilfs_cpfile_get_cpinfo -
566 * @cpfile:
567 * @cno:
568 * @ci:
569 * @nci:
570 */
Ryusuke Konishib028fcf2009-04-06 19:01:47 -0700571
572ssize_t nilfs_cpfile_get_cpinfo(struct inode *cpfile, __u64 *cnop, int mode,
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900573 void *buf, unsigned cisz, size_t nci)
Koji Sato29619802009-04-06 19:01:31 -0700574{
575 switch (mode) {
576 case NILFS_CHECKPOINT:
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900577 return nilfs_cpfile_do_get_cpinfo(cpfile, cnop, buf, cisz, nci);
Koji Sato29619802009-04-06 19:01:31 -0700578 case NILFS_SNAPSHOT:
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900579 return nilfs_cpfile_do_get_ssinfo(cpfile, cnop, buf, cisz, nci);
Koji Sato29619802009-04-06 19:01:31 -0700580 default:
581 return -EINVAL;
582 }
583}
584
585/**
586 * nilfs_cpfile_delete_checkpoint -
587 * @cpfile:
588 * @cno:
589 */
590int nilfs_cpfile_delete_checkpoint(struct inode *cpfile, __u64 cno)
591{
592 struct nilfs_cpinfo ci;
Ryusuke Konishi76068c42009-04-06 19:01:50 -0700593 __u64 tcno = cno;
Koji Sato29619802009-04-06 19:01:31 -0700594 ssize_t nci;
Koji Sato29619802009-04-06 19:01:31 -0700595
Ryusuke Konishi003ff182009-05-12 03:58:47 +0900596 nci = nilfs_cpfile_do_get_cpinfo(cpfile, &tcno, &ci, sizeof(ci), 1);
Koji Sato29619802009-04-06 19:01:31 -0700597 if (nci < 0)
598 return nci;
599 else if (nci == 0 || ci.ci_cno != cno)
600 return -ENOENT;
Ryusuke Konishi30c25be2009-05-30 19:08:09 +0900601 else if (nilfs_cpinfo_snapshot(&ci))
602 return -EBUSY;
Koji Sato29619802009-04-06 19:01:31 -0700603
604 return nilfs_cpfile_delete_checkpoints(cpfile, cno, cno + 1);
605}
606
607static struct nilfs_snapshot_list *
608nilfs_cpfile_block_get_snapshot_list(const struct inode *cpfile,
609 __u64 cno,
610 struct buffer_head *bh,
611 void *kaddr)
612{
613 struct nilfs_cpfile_header *header;
614 struct nilfs_checkpoint *cp;
615 struct nilfs_snapshot_list *list;
616
617 if (cno != 0) {
618 cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr);
619 list = &cp->cp_snapshot_list;
620 } else {
621 header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr);
622 list = &header->ch_snapshot_list;
623 }
624 return list;
625}
626
627static int nilfs_cpfile_set_snapshot(struct inode *cpfile, __u64 cno)
628{
629 struct buffer_head *header_bh, *curr_bh, *prev_bh, *cp_bh;
630 struct nilfs_cpfile_header *header;
631 struct nilfs_checkpoint *cp;
632 struct nilfs_snapshot_list *list;
633 __u64 curr, prev;
634 unsigned long curr_blkoff, prev_blkoff;
635 void *kaddr;
636 int ret;
637
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700638 if (cno == 0)
639 return -ENOENT; /* checkpoint number 0 is invalid */
Koji Sato29619802009-04-06 19:01:31 -0700640 down_write(&NILFS_MDT(cpfile)->mi_sem);
641
642 ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
643 if (ret < 0)
644 goto out_sem;
Cong Wang7b9c0972011-11-25 23:14:33 +0800645 kaddr = kmap_atomic(cp_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700646 cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
647 if (nilfs_checkpoint_invalid(cp)) {
648 ret = -ENOENT;
Cong Wang7b9c0972011-11-25 23:14:33 +0800649 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700650 goto out_cp;
651 }
652 if (nilfs_checkpoint_snapshot(cp)) {
653 ret = 0;
Cong Wang7b9c0972011-11-25 23:14:33 +0800654 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700655 goto out_cp;
656 }
Cong Wang7b9c0972011-11-25 23:14:33 +0800657 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700658
659 ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
660 if (ret < 0)
661 goto out_cp;
Cong Wang7b9c0972011-11-25 23:14:33 +0800662 kaddr = kmap_atomic(header_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700663 header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
664 list = &header->ch_snapshot_list;
665 curr_bh = header_bh;
666 get_bh(curr_bh);
667 curr = 0;
668 curr_blkoff = 0;
669 prev = le64_to_cpu(list->ssl_prev);
670 while (prev > cno) {
671 prev_blkoff = nilfs_cpfile_get_blkoff(cpfile, prev);
672 curr = prev;
673 if (curr_blkoff != prev_blkoff) {
Cong Wang7b9c0972011-11-25 23:14:33 +0800674 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700675 brelse(curr_bh);
676 ret = nilfs_cpfile_get_checkpoint_block(cpfile, curr,
677 0, &curr_bh);
678 if (ret < 0)
679 goto out_header;
Cong Wang7b9c0972011-11-25 23:14:33 +0800680 kaddr = kmap_atomic(curr_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700681 }
682 curr_blkoff = prev_blkoff;
683 cp = nilfs_cpfile_block_get_checkpoint(
684 cpfile, curr, curr_bh, kaddr);
685 list = &cp->cp_snapshot_list;
686 prev = le64_to_cpu(list->ssl_prev);
687 }
Cong Wang7b9c0972011-11-25 23:14:33 +0800688 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700689
690 if (prev != 0) {
691 ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0,
692 &prev_bh);
693 if (ret < 0)
694 goto out_curr;
695 } else {
696 prev_bh = header_bh;
697 get_bh(prev_bh);
698 }
699
Cong Wang7b9c0972011-11-25 23:14:33 +0800700 kaddr = kmap_atomic(curr_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700701 list = nilfs_cpfile_block_get_snapshot_list(
702 cpfile, curr, curr_bh, kaddr);
703 list->ssl_prev = cpu_to_le64(cno);
Cong Wang7b9c0972011-11-25 23:14:33 +0800704 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700705
Cong Wang7b9c0972011-11-25 23:14:33 +0800706 kaddr = kmap_atomic(cp_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700707 cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
708 cp->cp_snapshot_list.ssl_next = cpu_to_le64(curr);
709 cp->cp_snapshot_list.ssl_prev = cpu_to_le64(prev);
710 nilfs_checkpoint_set_snapshot(cp);
Cong Wang7b9c0972011-11-25 23:14:33 +0800711 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700712
Cong Wang7b9c0972011-11-25 23:14:33 +0800713 kaddr = kmap_atomic(prev_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700714 list = nilfs_cpfile_block_get_snapshot_list(
715 cpfile, prev, prev_bh, kaddr);
716 list->ssl_next = cpu_to_le64(cno);
Cong Wang7b9c0972011-11-25 23:14:33 +0800717 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700718
Cong Wang7b9c0972011-11-25 23:14:33 +0800719 kaddr = kmap_atomic(header_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700720 header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
721 le64_add_cpu(&header->ch_nsnapshots, 1);
Cong Wang7b9c0972011-11-25 23:14:33 +0800722 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700723
Ryusuke Konishi5fc7b142011-05-05 12:56:51 +0900724 mark_buffer_dirty(prev_bh);
725 mark_buffer_dirty(curr_bh);
726 mark_buffer_dirty(cp_bh);
727 mark_buffer_dirty(header_bh);
Koji Sato29619802009-04-06 19:01:31 -0700728 nilfs_mdt_mark_dirty(cpfile);
729
730 brelse(prev_bh);
731
732 out_curr:
733 brelse(curr_bh);
734
735 out_header:
736 brelse(header_bh);
737
738 out_cp:
739 brelse(cp_bh);
740
741 out_sem:
742 up_write(&NILFS_MDT(cpfile)->mi_sem);
743 return ret;
744}
745
746static int nilfs_cpfile_clear_snapshot(struct inode *cpfile, __u64 cno)
747{
748 struct buffer_head *header_bh, *next_bh, *prev_bh, *cp_bh;
749 struct nilfs_cpfile_header *header;
750 struct nilfs_checkpoint *cp;
751 struct nilfs_snapshot_list *list;
752 __u64 next, prev;
753 void *kaddr;
754 int ret;
755
Ryusuke Konishi1f5abe72009-04-06 19:01:55 -0700756 if (cno == 0)
757 return -ENOENT; /* checkpoint number 0 is invalid */
Koji Sato29619802009-04-06 19:01:31 -0700758 down_write(&NILFS_MDT(cpfile)->mi_sem);
759
760 ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
761 if (ret < 0)
762 goto out_sem;
Cong Wang7b9c0972011-11-25 23:14:33 +0800763 kaddr = kmap_atomic(cp_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700764 cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
765 if (nilfs_checkpoint_invalid(cp)) {
766 ret = -ENOENT;
Cong Wang7b9c0972011-11-25 23:14:33 +0800767 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700768 goto out_cp;
769 }
770 if (!nilfs_checkpoint_snapshot(cp)) {
771 ret = 0;
Cong Wang7b9c0972011-11-25 23:14:33 +0800772 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700773 goto out_cp;
774 }
775
776 list = &cp->cp_snapshot_list;
777 next = le64_to_cpu(list->ssl_next);
778 prev = le64_to_cpu(list->ssl_prev);
Cong Wang7b9c0972011-11-25 23:14:33 +0800779 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700780
781 ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
782 if (ret < 0)
783 goto out_cp;
784 if (next != 0) {
785 ret = nilfs_cpfile_get_checkpoint_block(cpfile, next, 0,
786 &next_bh);
787 if (ret < 0)
788 goto out_header;
789 } else {
790 next_bh = header_bh;
791 get_bh(next_bh);
792 }
793 if (prev != 0) {
794 ret = nilfs_cpfile_get_checkpoint_block(cpfile, prev, 0,
795 &prev_bh);
796 if (ret < 0)
797 goto out_next;
798 } else {
799 prev_bh = header_bh;
800 get_bh(prev_bh);
801 }
802
Cong Wang7b9c0972011-11-25 23:14:33 +0800803 kaddr = kmap_atomic(next_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700804 list = nilfs_cpfile_block_get_snapshot_list(
805 cpfile, next, next_bh, kaddr);
806 list->ssl_prev = cpu_to_le64(prev);
Cong Wang7b9c0972011-11-25 23:14:33 +0800807 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700808
Cong Wang7b9c0972011-11-25 23:14:33 +0800809 kaddr = kmap_atomic(prev_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700810 list = nilfs_cpfile_block_get_snapshot_list(
811 cpfile, prev, prev_bh, kaddr);
812 list->ssl_next = cpu_to_le64(next);
Cong Wang7b9c0972011-11-25 23:14:33 +0800813 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700814
Cong Wang7b9c0972011-11-25 23:14:33 +0800815 kaddr = kmap_atomic(cp_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700816 cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, cp_bh, kaddr);
817 cp->cp_snapshot_list.ssl_next = cpu_to_le64(0);
818 cp->cp_snapshot_list.ssl_prev = cpu_to_le64(0);
819 nilfs_checkpoint_clear_snapshot(cp);
Cong Wang7b9c0972011-11-25 23:14:33 +0800820 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700821
Cong Wang7b9c0972011-11-25 23:14:33 +0800822 kaddr = kmap_atomic(header_bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700823 header = nilfs_cpfile_block_get_header(cpfile, header_bh, kaddr);
824 le64_add_cpu(&header->ch_nsnapshots, -1);
Cong Wang7b9c0972011-11-25 23:14:33 +0800825 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700826
Ryusuke Konishi5fc7b142011-05-05 12:56:51 +0900827 mark_buffer_dirty(next_bh);
828 mark_buffer_dirty(prev_bh);
829 mark_buffer_dirty(cp_bh);
830 mark_buffer_dirty(header_bh);
Koji Sato29619802009-04-06 19:01:31 -0700831 nilfs_mdt_mark_dirty(cpfile);
832
833 brelse(prev_bh);
834
835 out_next:
836 brelse(next_bh);
837
838 out_header:
839 brelse(header_bh);
840
841 out_cp:
842 brelse(cp_bh);
843
844 out_sem:
845 up_write(&NILFS_MDT(cpfile)->mi_sem);
846 return ret;
847}
848
849/**
850 * nilfs_cpfile_is_snapshot -
851 * @cpfile: inode of checkpoint file
852 * @cno: checkpoint number
853 *
854 * Description:
855 *
856 * Return Value: On success, 1 is returned if the checkpoint specified by
857 * @cno is a snapshot, or 0 if not. On error, one of the following negative
858 * error codes is returned.
859 *
860 * %-EIO - I/O error.
861 *
862 * %-ENOMEM - Insufficient amount of memory available.
863 *
864 * %-ENOENT - No such checkpoint.
865 */
866int nilfs_cpfile_is_snapshot(struct inode *cpfile, __u64 cno)
867{
868 struct buffer_head *bh;
869 struct nilfs_checkpoint *cp;
870 void *kaddr;
871 int ret;
872
Zhu Yanhai43be0ec2009-08-12 14:17:59 +0800873 /* CP number is invalid if it's zero or larger than the
874 largest exist one.*/
875 if (cno == 0 || cno >= nilfs_mdt_cno(cpfile))
876 return -ENOENT;
Koji Sato29619802009-04-06 19:01:31 -0700877 down_read(&NILFS_MDT(cpfile)->mi_sem);
878
879 ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &bh);
880 if (ret < 0)
881 goto out;
Cong Wang7b9c0972011-11-25 23:14:33 +0800882 kaddr = kmap_atomic(bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700883 cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr);
Zhu Yanhai43be0ec2009-08-12 14:17:59 +0800884 if (nilfs_checkpoint_invalid(cp))
885 ret = -ENOENT;
886 else
887 ret = nilfs_checkpoint_snapshot(cp);
Cong Wang7b9c0972011-11-25 23:14:33 +0800888 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700889 brelse(bh);
890
891 out:
892 up_read(&NILFS_MDT(cpfile)->mi_sem);
893 return ret;
894}
895
896/**
897 * nilfs_cpfile_change_cpmode - change checkpoint mode
898 * @cpfile: inode of checkpoint file
899 * @cno: checkpoint number
900 * @status: mode of checkpoint
901 *
902 * Description: nilfs_change_cpmode() changes the mode of the checkpoint
903 * specified by @cno. The mode @mode is NILFS_CHECKPOINT or NILFS_SNAPSHOT.
904 *
905 * Return Value: On success, 0 is returned. On error, one of the following
906 * negative error codes is returned.
907 *
908 * %-EIO - I/O error.
909 *
910 * %-ENOMEM - Insufficient amount of memory available.
911 *
912 * %-ENOENT - No such checkpoint.
913 */
914int nilfs_cpfile_change_cpmode(struct inode *cpfile, __u64 cno, int mode)
915{
Koji Sato29619802009-04-06 19:01:31 -0700916 int ret;
917
Koji Sato29619802009-04-06 19:01:31 -0700918 switch (mode) {
919 case NILFS_CHECKPOINT:
Ryusuke Konishi032dbb32010-09-13 11:16:34 +0900920 if (nilfs_checkpoint_is_mounted(cpfile->i_sb, cno))
921 /*
922 * Current implementation does not have to protect
923 * plain read-only mounts since they are exclusive
924 * with a read/write mount and are protected from the
925 * cleaner.
926 */
Koji Sato29619802009-04-06 19:01:31 -0700927 ret = -EBUSY;
Ryusuke Konishi032dbb32010-09-13 11:16:34 +0900928 else
Koji Sato29619802009-04-06 19:01:31 -0700929 ret = nilfs_cpfile_clear_snapshot(cpfile, cno);
Koji Sato29619802009-04-06 19:01:31 -0700930 return ret;
931 case NILFS_SNAPSHOT:
932 return nilfs_cpfile_set_snapshot(cpfile, cno);
933 default:
934 return -EINVAL;
935 }
936}
937
938/**
939 * nilfs_cpfile_get_stat - get checkpoint statistics
940 * @cpfile: inode of checkpoint file
941 * @stat: pointer to a structure of checkpoint statistics
942 *
943 * Description: nilfs_cpfile_get_stat() returns information about checkpoints.
944 *
945 * Return Value: On success, 0 is returned, and checkpoints information is
946 * stored in the place pointed by @stat. On error, one of the following
947 * negative error codes is returned.
948 *
949 * %-EIO - I/O error.
950 *
951 * %-ENOMEM - Insufficient amount of memory available.
952 */
953int nilfs_cpfile_get_stat(struct inode *cpfile, struct nilfs_cpstat *cpstat)
954{
955 struct buffer_head *bh;
956 struct nilfs_cpfile_header *header;
957 void *kaddr;
958 int ret;
959
960 down_read(&NILFS_MDT(cpfile)->mi_sem);
961
962 ret = nilfs_cpfile_get_header_block(cpfile, &bh);
963 if (ret < 0)
964 goto out_sem;
Cong Wang7b9c0972011-11-25 23:14:33 +0800965 kaddr = kmap_atomic(bh->b_page);
Koji Sato29619802009-04-06 19:01:31 -0700966 header = nilfs_cpfile_block_get_header(cpfile, bh, kaddr);
967 cpstat->cs_cno = nilfs_mdt_cno(cpfile);
968 cpstat->cs_ncps = le64_to_cpu(header->ch_ncheckpoints);
969 cpstat->cs_nsss = le64_to_cpu(header->ch_nsnapshots);
Cong Wang7b9c0972011-11-25 23:14:33 +0800970 kunmap_atomic(kaddr);
Koji Sato29619802009-04-06 19:01:31 -0700971 brelse(bh);
972
973 out_sem:
974 up_read(&NILFS_MDT(cpfile)->mi_sem);
975 return ret;
976}
Ryusuke Konishi79739562009-11-12 23:56:43 +0900977
978/**
Ryusuke Konishif1e89c82010-09-05 12:20:59 +0900979 * nilfs_cpfile_read - read or get cpfile inode
980 * @sb: super block instance
Ryusuke Konishi79739562009-11-12 23:56:43 +0900981 * @cpsize: size of a checkpoint entry
Ryusuke Konishif1e89c82010-09-05 12:20:59 +0900982 * @raw_inode: on-disk cpfile inode
983 * @inodep: buffer to store the inode
Ryusuke Konishi79739562009-11-12 23:56:43 +0900984 */
Ryusuke Konishif1e89c82010-09-05 12:20:59 +0900985int nilfs_cpfile_read(struct super_block *sb, size_t cpsize,
986 struct nilfs_inode *raw_inode, struct inode **inodep)
Ryusuke Konishi79739562009-11-12 23:56:43 +0900987{
988 struct inode *cpfile;
Ryusuke Konishif1e89c82010-09-05 12:20:59 +0900989 int err;
Ryusuke Konishi79739562009-11-12 23:56:43 +0900990
Ryusuke Konishi0ec060d2014-04-03 14:50:31 -0700991 if (cpsize > sb->s_blocksize) {
992 printk(KERN_ERR
993 "NILFS: too large checkpoint size: %zu bytes.\n",
994 cpsize);
995 return -EINVAL;
996 } else if (cpsize < NILFS_MIN_CHECKPOINT_SIZE) {
997 printk(KERN_ERR
998 "NILFS: too small checkpoint size: %zu bytes.\n",
999 cpsize);
1000 return -EINVAL;
1001 }
1002
Ryusuke Konishif1e89c82010-09-05 12:20:59 +09001003 cpfile = nilfs_iget_locked(sb, NULL, NILFS_CPFILE_INO);
1004 if (unlikely(!cpfile))
1005 return -ENOMEM;
1006 if (!(cpfile->i_state & I_NEW))
1007 goto out;
1008
1009 err = nilfs_mdt_init(cpfile, NILFS_MDT_GFP, 0);
1010 if (err)
1011 goto failed;
1012
1013 nilfs_mdt_set_entry_size(cpfile, cpsize,
1014 sizeof(struct nilfs_cpfile_header));
1015
1016 err = nilfs_read_inode_common(cpfile, raw_inode);
1017 if (err)
1018 goto failed;
1019
1020 unlock_new_inode(cpfile);
1021 out:
1022 *inodep = cpfile;
1023 return 0;
1024 failed:
1025 iget_failed(cpfile);
1026 return err;
Ryusuke Konishi79739562009-11-12 23:56:43 +09001027}