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1/*
2 * dat.c - NILFS disk address translation.
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 * Written by Koji Sato.
17 */
18
19#include <linux/types.h>
20#include <linux/buffer_head.h>
21#include <linux/string.h>
22#include <linux/errno.h>
23#include "nilfs.h"
24#include "mdt.h"
25#include "alloc.h"
26#include "dat.h"
27
28
29#define NILFS_CNO_MIN ((__u64)1)
30#define NILFS_CNO_MAX (~(__u64)0)
31
32/**
33 * struct nilfs_dat_info - on-memory private data of DAT file
34 * @mi: on-memory private data of metadata file
35 * @palloc_cache: persistent object allocator cache of DAT file
36 * @shadow: shadow map of DAT file
37 */
38struct nilfs_dat_info {
39 struct nilfs_mdt_info mi;
40 struct nilfs_palloc_cache palloc_cache;
41 struct nilfs_shadow_map shadow;
42};
43
44static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat)
45{
46 return (struct nilfs_dat_info *)NILFS_MDT(dat);
47}
48
49static int nilfs_dat_prepare_entry(struct inode *dat,
50 struct nilfs_palloc_req *req, int create)
51{
52 return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
53 create, &req->pr_entry_bh);
54}
55
56static void nilfs_dat_commit_entry(struct inode *dat,
57 struct nilfs_palloc_req *req)
58{
59 mark_buffer_dirty(req->pr_entry_bh);
60 nilfs_mdt_mark_dirty(dat);
61 brelse(req->pr_entry_bh);
62}
63
64static void nilfs_dat_abort_entry(struct inode *dat,
65 struct nilfs_palloc_req *req)
66{
67 brelse(req->pr_entry_bh);
68}
69
70int nilfs_dat_prepare_alloc(struct inode *dat, struct nilfs_palloc_req *req)
71{
72 int ret;
73
74 ret = nilfs_palloc_prepare_alloc_entry(dat, req);
75 if (ret < 0)
76 return ret;
77
78 ret = nilfs_dat_prepare_entry(dat, req, 1);
79 if (ret < 0)
80 nilfs_palloc_abort_alloc_entry(dat, req);
81
82 return ret;
83}
84
85void nilfs_dat_commit_alloc(struct inode *dat, struct nilfs_palloc_req *req)
86{
87 struct nilfs_dat_entry *entry;
88 void *kaddr;
89
90 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
91 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
92 req->pr_entry_bh, kaddr);
93 entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
94 entry->de_end = cpu_to_le64(NILFS_CNO_MAX);
95 entry->de_blocknr = cpu_to_le64(0);
96 kunmap_atomic(kaddr);
97
98 nilfs_palloc_commit_alloc_entry(dat, req);
99 nilfs_dat_commit_entry(dat, req);
100}
101
102void nilfs_dat_abort_alloc(struct inode *dat, struct nilfs_palloc_req *req)
103{
104 nilfs_dat_abort_entry(dat, req);
105 nilfs_palloc_abort_alloc_entry(dat, req);
106}
107
108static void nilfs_dat_commit_free(struct inode *dat,
109 struct nilfs_palloc_req *req)
110{
111 struct nilfs_dat_entry *entry;
112 void *kaddr;
113
114 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
115 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
116 req->pr_entry_bh, kaddr);
117 entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
118 entry->de_end = cpu_to_le64(NILFS_CNO_MIN);
119 entry->de_blocknr = cpu_to_le64(0);
120 kunmap_atomic(kaddr);
121
122 nilfs_dat_commit_entry(dat, req);
123 nilfs_palloc_commit_free_entry(dat, req);
124}
125
126int nilfs_dat_prepare_start(struct inode *dat, struct nilfs_palloc_req *req)
127{
128 int ret;
129
130 ret = nilfs_dat_prepare_entry(dat, req, 0);
131 WARN_ON(ret == -ENOENT);
132 return ret;
133}
134
135void nilfs_dat_commit_start(struct inode *dat, struct nilfs_palloc_req *req,
136 sector_t blocknr)
137{
138 struct nilfs_dat_entry *entry;
139 void *kaddr;
140
141 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
142 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
143 req->pr_entry_bh, kaddr);
144 entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat));
145 entry->de_blocknr = cpu_to_le64(blocknr);
146 kunmap_atomic(kaddr);
147
148 nilfs_dat_commit_entry(dat, req);
149}
150
151int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req)
152{
153 struct nilfs_dat_entry *entry;
154 sector_t blocknr;
155 void *kaddr;
156 int ret;
157
158 ret = nilfs_dat_prepare_entry(dat, req, 0);
159 if (ret < 0) {
160 WARN_ON(ret == -ENOENT);
161 return ret;
162 }
163
164 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
165 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
166 req->pr_entry_bh, kaddr);
167 blocknr = le64_to_cpu(entry->de_blocknr);
168 kunmap_atomic(kaddr);
169
170 if (blocknr == 0) {
171 ret = nilfs_palloc_prepare_free_entry(dat, req);
172 if (ret < 0) {
173 nilfs_dat_abort_entry(dat, req);
174 return ret;
175 }
176 }
177
178 return 0;
179}
180
181void nilfs_dat_commit_end(struct inode *dat, struct nilfs_palloc_req *req,
182 int dead)
183{
184 struct nilfs_dat_entry *entry;
185 __u64 start, end;
186 sector_t blocknr;
187 void *kaddr;
188
189 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
190 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
191 req->pr_entry_bh, kaddr);
192 end = start = le64_to_cpu(entry->de_start);
193 if (!dead) {
194 end = nilfs_mdt_cno(dat);
195 WARN_ON(start > end);
196 }
197 entry->de_end = cpu_to_le64(end);
198 blocknr = le64_to_cpu(entry->de_blocknr);
199 kunmap_atomic(kaddr);
200
201 if (blocknr == 0)
202 nilfs_dat_commit_free(dat, req);
203 else
204 nilfs_dat_commit_entry(dat, req);
205}
206
207void nilfs_dat_abort_end(struct inode *dat, struct nilfs_palloc_req *req)
208{
209 struct nilfs_dat_entry *entry;
210 __u64 start;
211 sector_t blocknr;
212 void *kaddr;
213
214 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
215 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
216 req->pr_entry_bh, kaddr);
217 start = le64_to_cpu(entry->de_start);
218 blocknr = le64_to_cpu(entry->de_blocknr);
219 kunmap_atomic(kaddr);
220
221 if (start == nilfs_mdt_cno(dat) && blocknr == 0)
222 nilfs_palloc_abort_free_entry(dat, req);
223 nilfs_dat_abort_entry(dat, req);
224}
225
226int nilfs_dat_prepare_update(struct inode *dat,
227 struct nilfs_palloc_req *oldreq,
228 struct nilfs_palloc_req *newreq)
229{
230 int ret;
231
232 ret = nilfs_dat_prepare_end(dat, oldreq);
233 if (!ret) {
234 ret = nilfs_dat_prepare_alloc(dat, newreq);
235 if (ret < 0)
236 nilfs_dat_abort_end(dat, oldreq);
237 }
238 return ret;
239}
240
241void nilfs_dat_commit_update(struct inode *dat,
242 struct nilfs_palloc_req *oldreq,
243 struct nilfs_palloc_req *newreq, int dead)
244{
245 nilfs_dat_commit_end(dat, oldreq, dead);
246 nilfs_dat_commit_alloc(dat, newreq);
247}
248
249void nilfs_dat_abort_update(struct inode *dat,
250 struct nilfs_palloc_req *oldreq,
251 struct nilfs_palloc_req *newreq)
252{
253 nilfs_dat_abort_end(dat, oldreq);
254 nilfs_dat_abort_alloc(dat, newreq);
255}
256
257/**
258 * nilfs_dat_mark_dirty -
259 * @dat: DAT file inode
260 * @vblocknr: virtual block number
261 *
262 * Description:
263 *
264 * Return Value: On success, 0 is returned. On error, one of the following
265 * negative error codes is returned.
266 *
267 * %-EIO - I/O error.
268 *
269 * %-ENOMEM - Insufficient amount of memory available.
270 */
271int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
272{
273 struct nilfs_palloc_req req;
274 int ret;
275
276 req.pr_entry_nr = vblocknr;
277 ret = nilfs_dat_prepare_entry(dat, &req, 0);
278 if (ret == 0)
279 nilfs_dat_commit_entry(dat, &req);
280 return ret;
281}
282
283/**
284 * nilfs_dat_freev - free virtual block numbers
285 * @dat: DAT file inode
286 * @vblocknrs: array of virtual block numbers
287 * @nitems: number of virtual block numbers
288 *
289 * Description: nilfs_dat_freev() frees the virtual block numbers specified by
290 * @vblocknrs and @nitems.
291 *
292 * Return Value: On success, 0 is returned. On error, one of the following
293 * negative error codes is returned.
294 *
295 * %-EIO - I/O error.
296 *
297 * %-ENOMEM - Insufficient amount of memory available.
298 *
299 * %-ENOENT - The virtual block number have not been allocated.
300 */
301int nilfs_dat_freev(struct inode *dat, __u64 *vblocknrs, size_t nitems)
302{
303 return nilfs_palloc_freev(dat, vblocknrs, nitems);
304}
305
306/**
307 * nilfs_dat_move - change a block number
308 * @dat: DAT file inode
309 * @vblocknr: virtual block number
310 * @blocknr: block number
311 *
312 * Description: nilfs_dat_move() changes the block number associated with
313 * @vblocknr to @blocknr.
314 *
315 * Return Value: On success, 0 is returned. On error, one of the following
316 * negative error codes is returned.
317 *
318 * %-EIO - I/O error.
319 *
320 * %-ENOMEM - Insufficient amount of memory available.
321 */
322int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
323{
324 struct buffer_head *entry_bh;
325 struct nilfs_dat_entry *entry;
326 void *kaddr;
327 int ret;
328
329 ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
330 if (ret < 0)
331 return ret;
332
333 /*
334 * The given disk block number (blocknr) is not yet written to
335 * the device at this point.
336 *
337 * To prevent nilfs_dat_translate() from returning the
338 * uncommitted block number, this makes a copy of the entry
339 * buffer and redirects nilfs_dat_translate() to the copy.
340 */
341 if (!buffer_nilfs_redirected(entry_bh)) {
342 ret = nilfs_mdt_freeze_buffer(dat, entry_bh);
343 if (ret) {
344 brelse(entry_bh);
345 return ret;
346 }
347 }
348
349 kaddr = kmap_atomic(entry_bh->b_page);
350 entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
351 if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
352 nilfs_msg(dat->i_sb, KERN_CRIT,
353 "%s: invalid vblocknr = %llu, [%llu, %llu)",
354 __func__, (unsigned long long)vblocknr,
355 (unsigned long long)le64_to_cpu(entry->de_start),
356 (unsigned long long)le64_to_cpu(entry->de_end));
357 kunmap_atomic(kaddr);
358 brelse(entry_bh);
359 return -EINVAL;
360 }
361 WARN_ON(blocknr == 0);
362 entry->de_blocknr = cpu_to_le64(blocknr);
363 kunmap_atomic(kaddr);
364
365 mark_buffer_dirty(entry_bh);
366 nilfs_mdt_mark_dirty(dat);
367
368 brelse(entry_bh);
369
370 return 0;
371}
372
373/**
374 * nilfs_dat_translate - translate a virtual block number to a block number
375 * @dat: DAT file inode
376 * @vblocknr: virtual block number
377 * @blocknrp: pointer to a block number
378 *
379 * Description: nilfs_dat_translate() maps the virtual block number @vblocknr
380 * to the corresponding block number.
381 *
382 * Return Value: On success, 0 is returned and the block number associated
383 * with @vblocknr is stored in the place pointed by @blocknrp. On error, one
384 * of the following negative error codes is returned.
385 *
386 * %-EIO - I/O error.
387 *
388 * %-ENOMEM - Insufficient amount of memory available.
389 *
390 * %-ENOENT - A block number associated with @vblocknr does not exist.
391 */
392int nilfs_dat_translate(struct inode *dat, __u64 vblocknr, sector_t *blocknrp)
393{
394 struct buffer_head *entry_bh, *bh;
395 struct nilfs_dat_entry *entry;
396 sector_t blocknr;
397 void *kaddr;
398 int ret;
399
400 ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
401 if (ret < 0)
402 return ret;
403
404 if (!nilfs_doing_gc() && buffer_nilfs_redirected(entry_bh)) {
405 bh = nilfs_mdt_get_frozen_buffer(dat, entry_bh);
406 if (bh) {
407 WARN_ON(!buffer_uptodate(bh));
408 brelse(entry_bh);
409 entry_bh = bh;
410 }
411 }
412
413 kaddr = kmap_atomic(entry_bh->b_page);
414 entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
415 blocknr = le64_to_cpu(entry->de_blocknr);
416 if (blocknr == 0) {
417 ret = -ENOENT;
418 goto out;
419 }
420 *blocknrp = blocknr;
421
422 out:
423 kunmap_atomic(kaddr);
424 brelse(entry_bh);
425 return ret;
426}
427
428ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned int visz,
429 size_t nvi)
430{
431 struct buffer_head *entry_bh;
432 struct nilfs_dat_entry *entry;
433 struct nilfs_vinfo *vinfo = buf;
434 __u64 first, last;
435 void *kaddr;
436 unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
437 int i, j, n, ret;
438
439 for (i = 0; i < nvi; i += n) {
440 ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
441 0, &entry_bh);
442 if (ret < 0)
443 return ret;
444 kaddr = kmap_atomic(entry_bh->b_page);
445 /* last virtual block number in this block */
446 first = vinfo->vi_vblocknr;
447 do_div(first, entries_per_block);
448 first *= entries_per_block;
449 last = first + entries_per_block - 1;
450 for (j = i, n = 0;
451 j < nvi && vinfo->vi_vblocknr >= first &&
452 vinfo->vi_vblocknr <= last;
453 j++, n++, vinfo = (void *)vinfo + visz) {
454 entry = nilfs_palloc_block_get_entry(
455 dat, vinfo->vi_vblocknr, entry_bh, kaddr);
456 vinfo->vi_start = le64_to_cpu(entry->de_start);
457 vinfo->vi_end = le64_to_cpu(entry->de_end);
458 vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
459 }
460 kunmap_atomic(kaddr);
461 brelse(entry_bh);
462 }
463
464 return nvi;
465}
466
467/**
468 * nilfs_dat_read - read or get dat inode
469 * @sb: super block instance
470 * @entry_size: size of a dat entry
471 * @raw_inode: on-disk dat inode
472 * @inodep: buffer to store the inode
473 */
474int nilfs_dat_read(struct super_block *sb, size_t entry_size,
475 struct nilfs_inode *raw_inode, struct inode **inodep)
476{
477 static struct lock_class_key dat_lock_key;
478 struct inode *dat;
479 struct nilfs_dat_info *di;
480 int err;
481
482 if (entry_size > sb->s_blocksize) {
483 nilfs_msg(sb, KERN_ERR, "too large DAT entry size: %zu bytes",
484 entry_size);
485 return -EINVAL;
486 } else if (entry_size < NILFS_MIN_DAT_ENTRY_SIZE) {
487 nilfs_msg(sb, KERN_ERR, "too small DAT entry size: %zu bytes",
488 entry_size);
489 return -EINVAL;
490 }
491
492 dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO);
493 if (unlikely(!dat))
494 return -ENOMEM;
495 if (!(dat->i_state & I_NEW))
496 goto out;
497
498 err = nilfs_mdt_init(dat, NILFS_MDT_GFP, sizeof(*di));
499 if (err)
500 goto failed;
501
502 err = nilfs_palloc_init_blockgroup(dat, entry_size);
503 if (err)
504 goto failed;
505
506 di = NILFS_DAT_I(dat);
507 lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
508 nilfs_palloc_setup_cache(dat, &di->palloc_cache);
509 nilfs_mdt_setup_shadow_map(dat, &di->shadow);
510
511 err = nilfs_read_inode_common(dat, raw_inode);
512 if (err)
513 goto failed;
514
515 unlock_new_inode(dat);
516 out:
517 *inodep = dat;
518 return 0;
519 failed:
520 iget_failed(dat);
521 return err;
522}
1/*
2 * dat.c - NILFS disk address translation.
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/types.h>
24#include <linux/buffer_head.h>
25#include <linux/string.h>
26#include <linux/errno.h>
27#include "nilfs.h"
28#include "mdt.h"
29#include "alloc.h"
30#include "dat.h"
31
32
33#define NILFS_CNO_MIN ((__u64)1)
34#define NILFS_CNO_MAX (~(__u64)0)
35
36/**
37 * struct nilfs_dat_info - on-memory private data of DAT file
38 * @mi: on-memory private data of metadata file
39 * @palloc_cache: persistent object allocator cache of DAT file
40 * @shadow: shadow map of DAT file
41 */
42struct nilfs_dat_info {
43 struct nilfs_mdt_info mi;
44 struct nilfs_palloc_cache palloc_cache;
45 struct nilfs_shadow_map shadow;
46};
47
48static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat)
49{
50 return (struct nilfs_dat_info *)NILFS_MDT(dat);
51}
52
53static int nilfs_dat_prepare_entry(struct inode *dat,
54 struct nilfs_palloc_req *req, int create)
55{
56 return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
57 create, &req->pr_entry_bh);
58}
59
60static void nilfs_dat_commit_entry(struct inode *dat,
61 struct nilfs_palloc_req *req)
62{
63 mark_buffer_dirty(req->pr_entry_bh);
64 nilfs_mdt_mark_dirty(dat);
65 brelse(req->pr_entry_bh);
66}
67
68static void nilfs_dat_abort_entry(struct inode *dat,
69 struct nilfs_palloc_req *req)
70{
71 brelse(req->pr_entry_bh);
72}
73
74int nilfs_dat_prepare_alloc(struct inode *dat, struct nilfs_palloc_req *req)
75{
76 int ret;
77
78 ret = nilfs_palloc_prepare_alloc_entry(dat, req);
79 if (ret < 0)
80 return ret;
81
82 ret = nilfs_dat_prepare_entry(dat, req, 1);
83 if (ret < 0)
84 nilfs_palloc_abort_alloc_entry(dat, req);
85
86 return ret;
87}
88
89void nilfs_dat_commit_alloc(struct inode *dat, struct nilfs_palloc_req *req)
90{
91 struct nilfs_dat_entry *entry;
92 void *kaddr;
93
94 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
95 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
96 req->pr_entry_bh, kaddr);
97 entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
98 entry->de_end = cpu_to_le64(NILFS_CNO_MAX);
99 entry->de_blocknr = cpu_to_le64(0);
100 kunmap_atomic(kaddr);
101
102 nilfs_palloc_commit_alloc_entry(dat, req);
103 nilfs_dat_commit_entry(dat, req);
104}
105
106void nilfs_dat_abort_alloc(struct inode *dat, struct nilfs_palloc_req *req)
107{
108 nilfs_dat_abort_entry(dat, req);
109 nilfs_palloc_abort_alloc_entry(dat, req);
110}
111
112static void nilfs_dat_commit_free(struct inode *dat,
113 struct nilfs_palloc_req *req)
114{
115 struct nilfs_dat_entry *entry;
116 void *kaddr;
117
118 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
119 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
120 req->pr_entry_bh, kaddr);
121 entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
122 entry->de_end = cpu_to_le64(NILFS_CNO_MIN);
123 entry->de_blocknr = cpu_to_le64(0);
124 kunmap_atomic(kaddr);
125
126 nilfs_dat_commit_entry(dat, req);
127 nilfs_palloc_commit_free_entry(dat, req);
128}
129
130int nilfs_dat_prepare_start(struct inode *dat, struct nilfs_palloc_req *req)
131{
132 int ret;
133
134 ret = nilfs_dat_prepare_entry(dat, req, 0);
135 WARN_ON(ret == -ENOENT);
136 return ret;
137}
138
139void nilfs_dat_commit_start(struct inode *dat, struct nilfs_palloc_req *req,
140 sector_t blocknr)
141{
142 struct nilfs_dat_entry *entry;
143 void *kaddr;
144
145 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
146 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
147 req->pr_entry_bh, kaddr);
148 entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat));
149 entry->de_blocknr = cpu_to_le64(blocknr);
150 kunmap_atomic(kaddr);
151
152 nilfs_dat_commit_entry(dat, req);
153}
154
155int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req)
156{
157 struct nilfs_dat_entry *entry;
158 __u64 start;
159 sector_t blocknr;
160 void *kaddr;
161 int ret;
162
163 ret = nilfs_dat_prepare_entry(dat, req, 0);
164 if (ret < 0) {
165 WARN_ON(ret == -ENOENT);
166 return ret;
167 }
168
169 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
170 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
171 req->pr_entry_bh, kaddr);
172 start = le64_to_cpu(entry->de_start);
173 blocknr = le64_to_cpu(entry->de_blocknr);
174 kunmap_atomic(kaddr);
175
176 if (blocknr == 0) {
177 ret = nilfs_palloc_prepare_free_entry(dat, req);
178 if (ret < 0) {
179 nilfs_dat_abort_entry(dat, req);
180 return ret;
181 }
182 }
183
184 return 0;
185}
186
187void nilfs_dat_commit_end(struct inode *dat, struct nilfs_palloc_req *req,
188 int dead)
189{
190 struct nilfs_dat_entry *entry;
191 __u64 start, end;
192 sector_t blocknr;
193 void *kaddr;
194
195 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
196 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
197 req->pr_entry_bh, kaddr);
198 end = start = le64_to_cpu(entry->de_start);
199 if (!dead) {
200 end = nilfs_mdt_cno(dat);
201 WARN_ON(start > end);
202 }
203 entry->de_end = cpu_to_le64(end);
204 blocknr = le64_to_cpu(entry->de_blocknr);
205 kunmap_atomic(kaddr);
206
207 if (blocknr == 0)
208 nilfs_dat_commit_free(dat, req);
209 else
210 nilfs_dat_commit_entry(dat, req);
211}
212
213void nilfs_dat_abort_end(struct inode *dat, struct nilfs_palloc_req *req)
214{
215 struct nilfs_dat_entry *entry;
216 __u64 start;
217 sector_t blocknr;
218 void *kaddr;
219
220 kaddr = kmap_atomic(req->pr_entry_bh->b_page);
221 entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
222 req->pr_entry_bh, kaddr);
223 start = le64_to_cpu(entry->de_start);
224 blocknr = le64_to_cpu(entry->de_blocknr);
225 kunmap_atomic(kaddr);
226
227 if (start == nilfs_mdt_cno(dat) && blocknr == 0)
228 nilfs_palloc_abort_free_entry(dat, req);
229 nilfs_dat_abort_entry(dat, req);
230}
231
232int nilfs_dat_prepare_update(struct inode *dat,
233 struct nilfs_palloc_req *oldreq,
234 struct nilfs_palloc_req *newreq)
235{
236 int ret;
237
238 ret = nilfs_dat_prepare_end(dat, oldreq);
239 if (!ret) {
240 ret = nilfs_dat_prepare_alloc(dat, newreq);
241 if (ret < 0)
242 nilfs_dat_abort_end(dat, oldreq);
243 }
244 return ret;
245}
246
247void nilfs_dat_commit_update(struct inode *dat,
248 struct nilfs_palloc_req *oldreq,
249 struct nilfs_palloc_req *newreq, int dead)
250{
251 nilfs_dat_commit_end(dat, oldreq, dead);
252 nilfs_dat_commit_alloc(dat, newreq);
253}
254
255void nilfs_dat_abort_update(struct inode *dat,
256 struct nilfs_palloc_req *oldreq,
257 struct nilfs_palloc_req *newreq)
258{
259 nilfs_dat_abort_end(dat, oldreq);
260 nilfs_dat_abort_alloc(dat, newreq);
261}
262
263/**
264 * nilfs_dat_mark_dirty -
265 * @dat: DAT file inode
266 * @vblocknr: virtual block number
267 *
268 * Description:
269 *
270 * Return Value: On success, 0 is returned. On error, one of the following
271 * negative error codes is returned.
272 *
273 * %-EIO - I/O error.
274 *
275 * %-ENOMEM - Insufficient amount of memory available.
276 */
277int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
278{
279 struct nilfs_palloc_req req;
280 int ret;
281
282 req.pr_entry_nr = vblocknr;
283 ret = nilfs_dat_prepare_entry(dat, &req, 0);
284 if (ret == 0)
285 nilfs_dat_commit_entry(dat, &req);
286 return ret;
287}
288
289/**
290 * nilfs_dat_freev - free virtual block numbers
291 * @dat: DAT file inode
292 * @vblocknrs: array of virtual block numbers
293 * @nitems: number of virtual block numbers
294 *
295 * Description: nilfs_dat_freev() frees the virtual block numbers specified by
296 * @vblocknrs and @nitems.
297 *
298 * Return Value: On success, 0 is returned. On error, one of the following
299 * negative error codes is returned.
300 *
301 * %-EIO - I/O error.
302 *
303 * %-ENOMEM - Insufficient amount of memory available.
304 *
305 * %-ENOENT - The virtual block number have not been allocated.
306 */
307int nilfs_dat_freev(struct inode *dat, __u64 *vblocknrs, size_t nitems)
308{
309 return nilfs_palloc_freev(dat, vblocknrs, nitems);
310}
311
312/**
313 * nilfs_dat_move - change a block number
314 * @dat: DAT file inode
315 * @vblocknr: virtual block number
316 * @blocknr: block number
317 *
318 * Description: nilfs_dat_move() changes the block number associated with
319 * @vblocknr to @blocknr.
320 *
321 * Return Value: On success, 0 is returned. On error, one of the following
322 * negative error codes is returned.
323 *
324 * %-EIO - I/O error.
325 *
326 * %-ENOMEM - Insufficient amount of memory available.
327 */
328int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
329{
330 struct buffer_head *entry_bh;
331 struct nilfs_dat_entry *entry;
332 void *kaddr;
333 int ret;
334
335 ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
336 if (ret < 0)
337 return ret;
338
339 /*
340 * The given disk block number (blocknr) is not yet written to
341 * the device at this point.
342 *
343 * To prevent nilfs_dat_translate() from returning the
344 * uncommitted block number, this makes a copy of the entry
345 * buffer and redirects nilfs_dat_translate() to the copy.
346 */
347 if (!buffer_nilfs_redirected(entry_bh)) {
348 ret = nilfs_mdt_freeze_buffer(dat, entry_bh);
349 if (ret) {
350 brelse(entry_bh);
351 return ret;
352 }
353 }
354
355 kaddr = kmap_atomic(entry_bh->b_page);
356 entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
357 if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
358 printk(KERN_CRIT "%s: vbn = %llu, [%llu, %llu)\n", __func__,
359 (unsigned long long)vblocknr,
360 (unsigned long long)le64_to_cpu(entry->de_start),
361 (unsigned long long)le64_to_cpu(entry->de_end));
362 kunmap_atomic(kaddr);
363 brelse(entry_bh);
364 return -EINVAL;
365 }
366 WARN_ON(blocknr == 0);
367 entry->de_blocknr = cpu_to_le64(blocknr);
368 kunmap_atomic(kaddr);
369
370 mark_buffer_dirty(entry_bh);
371 nilfs_mdt_mark_dirty(dat);
372
373 brelse(entry_bh);
374
375 return 0;
376}
377
378/**
379 * nilfs_dat_translate - translate a virtual block number to a block number
380 * @dat: DAT file inode
381 * @vblocknr: virtual block number
382 * @blocknrp: pointer to a block number
383 *
384 * Description: nilfs_dat_translate() maps the virtual block number @vblocknr
385 * to the corresponding block number.
386 *
387 * Return Value: On success, 0 is returned and the block number associated
388 * with @vblocknr is stored in the place pointed by @blocknrp. On error, one
389 * of the following negative error codes is returned.
390 *
391 * %-EIO - I/O error.
392 *
393 * %-ENOMEM - Insufficient amount of memory available.
394 *
395 * %-ENOENT - A block number associated with @vblocknr does not exist.
396 */
397int nilfs_dat_translate(struct inode *dat, __u64 vblocknr, sector_t *blocknrp)
398{
399 struct buffer_head *entry_bh, *bh;
400 struct nilfs_dat_entry *entry;
401 sector_t blocknr;
402 void *kaddr;
403 int ret;
404
405 ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
406 if (ret < 0)
407 return ret;
408
409 if (!nilfs_doing_gc() && buffer_nilfs_redirected(entry_bh)) {
410 bh = nilfs_mdt_get_frozen_buffer(dat, entry_bh);
411 if (bh) {
412 WARN_ON(!buffer_uptodate(bh));
413 brelse(entry_bh);
414 entry_bh = bh;
415 }
416 }
417
418 kaddr = kmap_atomic(entry_bh->b_page);
419 entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
420 blocknr = le64_to_cpu(entry->de_blocknr);
421 if (blocknr == 0) {
422 ret = -ENOENT;
423 goto out;
424 }
425 *blocknrp = blocknr;
426
427 out:
428 kunmap_atomic(kaddr);
429 brelse(entry_bh);
430 return ret;
431}
432
433ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned visz,
434 size_t nvi)
435{
436 struct buffer_head *entry_bh;
437 struct nilfs_dat_entry *entry;
438 struct nilfs_vinfo *vinfo = buf;
439 __u64 first, last;
440 void *kaddr;
441 unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
442 int i, j, n, ret;
443
444 for (i = 0; i < nvi; i += n) {
445 ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
446 0, &entry_bh);
447 if (ret < 0)
448 return ret;
449 kaddr = kmap_atomic(entry_bh->b_page);
450 /* last virtual block number in this block */
451 first = vinfo->vi_vblocknr;
452 do_div(first, entries_per_block);
453 first *= entries_per_block;
454 last = first + entries_per_block - 1;
455 for (j = i, n = 0;
456 j < nvi && vinfo->vi_vblocknr >= first &&
457 vinfo->vi_vblocknr <= last;
458 j++, n++, vinfo = (void *)vinfo + visz) {
459 entry = nilfs_palloc_block_get_entry(
460 dat, vinfo->vi_vblocknr, entry_bh, kaddr);
461 vinfo->vi_start = le64_to_cpu(entry->de_start);
462 vinfo->vi_end = le64_to_cpu(entry->de_end);
463 vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
464 }
465 kunmap_atomic(kaddr);
466 brelse(entry_bh);
467 }
468
469 return nvi;
470}
471
472/**
473 * nilfs_dat_read - read or get dat inode
474 * @sb: super block instance
475 * @entry_size: size of a dat entry
476 * @raw_inode: on-disk dat inode
477 * @inodep: buffer to store the inode
478 */
479int nilfs_dat_read(struct super_block *sb, size_t entry_size,
480 struct nilfs_inode *raw_inode, struct inode **inodep)
481{
482 static struct lock_class_key dat_lock_key;
483 struct inode *dat;
484 struct nilfs_dat_info *di;
485 int err;
486
487 if (entry_size > sb->s_blocksize) {
488 printk(KERN_ERR
489 "NILFS: too large DAT entry size: %zu bytes.\n",
490 entry_size);
491 return -EINVAL;
492 } else if (entry_size < NILFS_MIN_DAT_ENTRY_SIZE) {
493 printk(KERN_ERR
494 "NILFS: too small DAT entry size: %zu bytes.\n",
495 entry_size);
496 return -EINVAL;
497 }
498
499 dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO);
500 if (unlikely(!dat))
501 return -ENOMEM;
502 if (!(dat->i_state & I_NEW))
503 goto out;
504
505 err = nilfs_mdt_init(dat, NILFS_MDT_GFP, sizeof(*di));
506 if (err)
507 goto failed;
508
509 err = nilfs_palloc_init_blockgroup(dat, entry_size);
510 if (err)
511 goto failed;
512
513 di = NILFS_DAT_I(dat);
514 lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
515 nilfs_palloc_setup_cache(dat, &di->palloc_cache);
516 nilfs_mdt_setup_shadow_map(dat, &di->shadow);
517
518 err = nilfs_read_inode_common(dat, raw_inode);
519 if (err)
520 goto failed;
521
522 unlock_new_inode(dat);
523 out:
524 *inodep = dat;
525 return 0;
526 failed:
527 iget_failed(dat);
528 return err;
529}