2 * sufile.c - NILFS segment usage file.
4 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
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.
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.
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
20 * Written by Koji Sato <koji@osrg.net>.
23 #include <linux/kernel.h>
25 #include <linux/string.h>
26 #include <linux/buffer_head.h>
27 #include <linux/errno.h>
28 #include <linux/nilfs2_fs.h>
33 static inline unsigned long
34 nilfs_sufile_segment_usages_per_block(const struct inode
*sufile
)
36 return NILFS_MDT(sufile
)->mi_entries_per_block
;
40 nilfs_sufile_get_blkoff(const struct inode
*sufile
, __u64 segnum
)
42 __u64 t
= segnum
+ NILFS_MDT(sufile
)->mi_first_entry_offset
;
43 do_div(t
, nilfs_sufile_segment_usages_per_block(sufile
));
44 return (unsigned long)t
;
48 nilfs_sufile_get_offset(const struct inode
*sufile
, __u64 segnum
)
50 __u64 t
= segnum
+ NILFS_MDT(sufile
)->mi_first_entry_offset
;
51 return do_div(t
, nilfs_sufile_segment_usages_per_block(sufile
));
55 nilfs_sufile_segment_usages_in_block(const struct inode
*sufile
, __u64 curr
,
58 return min_t(unsigned long,
59 nilfs_sufile_segment_usages_per_block(sufile
) -
60 nilfs_sufile_get_offset(sufile
, curr
),
64 static inline struct nilfs_sufile_header
*
65 nilfs_sufile_block_get_header(const struct inode
*sufile
,
66 struct buffer_head
*bh
,
69 return kaddr
+ bh_offset(bh
);
72 static struct nilfs_segment_usage
*
73 nilfs_sufile_block_get_segment_usage(const struct inode
*sufile
, __u64 segnum
,
74 struct buffer_head
*bh
, void *kaddr
)
76 return kaddr
+ bh_offset(bh
) +
77 nilfs_sufile_get_offset(sufile
, segnum
) *
78 NILFS_MDT(sufile
)->mi_entry_size
;
81 static inline int nilfs_sufile_get_header_block(struct inode
*sufile
,
82 struct buffer_head
**bhp
)
84 return nilfs_mdt_get_block(sufile
, 0, 0, NULL
, bhp
);
88 nilfs_sufile_get_segment_usage_block(struct inode
*sufile
, __u64 segnum
,
89 int create
, struct buffer_head
**bhp
)
91 return nilfs_mdt_get_block(sufile
,
92 nilfs_sufile_get_blkoff(sufile
, segnum
),
97 * nilfs_sufile_alloc - allocate a segment
98 * @sufile: inode of segment usage file
99 * @segnump: pointer to segment number
101 * Description: nilfs_sufile_alloc() allocates a clean segment.
103 * Return Value: On success, 0 is returned and the segment number of the
104 * allocated segment is stored in the place pointed by @segnump. On error, one
105 * of the following negative error codes is returned.
109 * %-ENOMEM - Insufficient amount of memory available.
111 * %-ENOSPC - No clean segment left.
113 int nilfs_sufile_alloc(struct inode
*sufile
, __u64
*segnump
)
115 struct buffer_head
*header_bh
, *su_bh
;
116 struct the_nilfs
*nilfs
;
117 struct nilfs_sufile_header
*header
;
118 struct nilfs_segment_usage
*su
;
119 size_t susz
= NILFS_MDT(sufile
)->mi_entry_size
;
120 __u64 segnum
, maxsegnum
, last_alloc
;
122 unsigned long nsegments
, ncleansegs
, nsus
;
125 down_write(&NILFS_MDT(sufile
)->mi_sem
);
127 nilfs
= NILFS_MDT(sufile
)->mi_nilfs
;
129 ret
= nilfs_sufile_get_header_block(sufile
, &header_bh
);
132 kaddr
= kmap_atomic(header_bh
->b_page
, KM_USER0
);
133 header
= nilfs_sufile_block_get_header(sufile
, header_bh
, kaddr
);
134 ncleansegs
= le64_to_cpu(header
->sh_ncleansegs
);
135 last_alloc
= le64_to_cpu(header
->sh_last_alloc
);
136 kunmap_atomic(kaddr
, KM_USER0
);
138 nsegments
= nilfs_sufile_get_nsegments(sufile
);
139 segnum
= last_alloc
+ 1;
140 maxsegnum
= nsegments
- 1;
141 for (i
= 0; i
< nsegments
; i
+= nsus
) {
142 if (segnum
>= nsegments
) {
145 maxsegnum
= last_alloc
;
147 ret
= nilfs_sufile_get_segment_usage_block(sufile
, segnum
, 1,
151 kaddr
= kmap_atomic(su_bh
->b_page
, KM_USER0
);
152 su
= nilfs_sufile_block_get_segment_usage(
153 sufile
, segnum
, su_bh
, kaddr
);
155 nsus
= nilfs_sufile_segment_usages_in_block(
156 sufile
, segnum
, maxsegnum
);
157 for (j
= 0; j
< nsus
; j
++, su
= (void *)su
+ susz
, segnum
++) {
158 if (!nilfs_segment_usage_clean(su
))
160 /* found a clean segment */
161 nilfs_segment_usage_set_dirty(su
);
162 kunmap_atomic(kaddr
, KM_USER0
);
164 kaddr
= kmap_atomic(header_bh
->b_page
, KM_USER0
);
165 header
= nilfs_sufile_block_get_header(
166 sufile
, header_bh
, kaddr
);
167 le64_add_cpu(&header
->sh_ncleansegs
, -1);
168 le64_add_cpu(&header
->sh_ndirtysegs
, 1);
169 header
->sh_last_alloc
= cpu_to_le64(segnum
);
170 kunmap_atomic(kaddr
, KM_USER0
);
172 nilfs_mdt_mark_buffer_dirty(header_bh
);
173 nilfs_mdt_mark_buffer_dirty(su_bh
);
174 nilfs_mdt_mark_dirty(sufile
);
180 kunmap_atomic(kaddr
, KM_USER0
);
184 /* no segments left */
191 up_write(&NILFS_MDT(sufile
)->mi_sem
);
196 * nilfs_sufile_cancel_free -
197 * @sufile: inode of segment usage file
198 * @segnum: segment number
202 * Return Value: On success, 0 is returned. On error, one of the following
203 * negative error codes is returned.
207 * %-ENOMEM - Insufficient amount of memory available.
209 int nilfs_sufile_cancel_free(struct inode
*sufile
, __u64 segnum
)
211 struct buffer_head
*header_bh
, *su_bh
;
212 struct the_nilfs
*nilfs
;
213 struct nilfs_sufile_header
*header
;
214 struct nilfs_segment_usage
*su
;
218 down_write(&NILFS_MDT(sufile
)->mi_sem
);
220 nilfs
= NILFS_MDT(sufile
)->mi_nilfs
;
222 ret
= nilfs_sufile_get_header_block(sufile
, &header_bh
);
226 ret
= nilfs_sufile_get_segment_usage_block(sufile
, segnum
, 0, &su_bh
);
230 kaddr
= kmap_atomic(su_bh
->b_page
, KM_USER0
);
231 su
= nilfs_sufile_block_get_segment_usage(
232 sufile
, segnum
, su_bh
, kaddr
);
233 if (unlikely(!nilfs_segment_usage_clean(su
))) {
234 printk(KERN_WARNING
"%s: segment %llu must be clean\n",
235 __func__
, (unsigned long long)segnum
);
236 kunmap_atomic(kaddr
, KM_USER0
);
239 nilfs_segment_usage_set_dirty(su
);
240 kunmap_atomic(kaddr
, KM_USER0
);
242 kaddr
= kmap_atomic(header_bh
->b_page
, KM_USER0
);
243 header
= nilfs_sufile_block_get_header(sufile
, header_bh
, kaddr
);
244 le64_add_cpu(&header
->sh_ncleansegs
, -1);
245 le64_add_cpu(&header
->sh_ndirtysegs
, 1);
246 kunmap_atomic(kaddr
, KM_USER0
);
248 nilfs_mdt_mark_buffer_dirty(header_bh
);
249 nilfs_mdt_mark_buffer_dirty(su_bh
);
250 nilfs_mdt_mark_dirty(sufile
);
257 up_write(&NILFS_MDT(sufile
)->mi_sem
);
262 * nilfs_sufile_freev - free segments
263 * @sufile: inode of segment usage file
264 * @segnum: array of segment numbers
265 * @nsegs: number of segments
267 * Description: nilfs_sufile_freev() frees segments specified by @segnum and
268 * @nsegs, which must have been returned by a previous call to
269 * nilfs_sufile_alloc().
271 * Return Value: On success, 0 is returned. On error, one of the following
272 * negative error codes is returned.
276 * %-ENOMEM - Insufficient amount of memory available.
278 #define NILFS_SUFILE_FREEV_PREALLOC 16
279 int nilfs_sufile_freev(struct inode
*sufile
, __u64
*segnum
, size_t nsegs
)
281 struct buffer_head
*header_bh
, **su_bh
,
282 *su_bh_prealloc
[NILFS_SUFILE_FREEV_PREALLOC
];
283 struct the_nilfs
*nilfs
;
284 struct nilfs_sufile_header
*header
;
285 struct nilfs_segment_usage
*su
;
289 down_write(&NILFS_MDT(sufile
)->mi_sem
);
291 nilfs
= NILFS_MDT(sufile
)->mi_nilfs
;
293 /* prepare resources */
294 if (nsegs
<= NILFS_SUFILE_FREEV_PREALLOC
)
295 su_bh
= su_bh_prealloc
;
297 su_bh
= kmalloc(sizeof(*su_bh
) * nsegs
, GFP_NOFS
);
304 ret
= nilfs_sufile_get_header_block(sufile
, &header_bh
);
307 for (i
= 0; i
< nsegs
; i
++) {
308 ret
= nilfs_sufile_get_segment_usage_block(sufile
, segnum
[i
],
315 for (i
= 0; i
< nsegs
; i
++) {
316 kaddr
= kmap_atomic(su_bh
[i
]->b_page
, KM_USER0
);
317 su
= nilfs_sufile_block_get_segment_usage(
318 sufile
, segnum
[i
], su_bh
[i
], kaddr
);
319 WARN_ON(nilfs_segment_usage_error(su
));
320 nilfs_segment_usage_set_clean(su
);
321 kunmap_atomic(kaddr
, KM_USER0
);
322 nilfs_mdt_mark_buffer_dirty(su_bh
[i
]);
324 kaddr
= kmap_atomic(header_bh
->b_page
, KM_USER0
);
325 header
= nilfs_sufile_block_get_header(sufile
, header_bh
, kaddr
);
326 le64_add_cpu(&header
->sh_ncleansegs
, nsegs
);
327 le64_add_cpu(&header
->sh_ndirtysegs
, -(u64
)nsegs
);
328 kunmap_atomic(kaddr
, KM_USER0
);
329 nilfs_mdt_mark_buffer_dirty(header_bh
);
330 nilfs_mdt_mark_dirty(sufile
);
333 for (i
--; i
>= 0; i
--)
338 if (su_bh
!= su_bh_prealloc
)
342 up_write(&NILFS_MDT(sufile
)->mi_sem
);
347 * nilfs_sufile_free -
351 int nilfs_sufile_free(struct inode
*sufile
, __u64 segnum
)
353 return nilfs_sufile_freev(sufile
, &segnum
, 1);
357 * nilfs_sufile_get_segment_usage - get a segment usage
358 * @sufile: inode of segment usage file
359 * @segnum: segment number
360 * @sup: pointer to segment usage
361 * @bhp: pointer to buffer head
363 * Description: nilfs_sufile_get_segment_usage() acquires the segment usage
364 * specified by @segnum.
366 * Return Value: On success, 0 is returned, and the segment usage and the
367 * buffer head of the buffer on which the segment usage is located are stored
368 * in the place pointed by @sup and @bhp, respectively. On error, one of the
369 * following negative error codes is returned.
373 * %-ENOMEM - Insufficient amount of memory available.
375 * %-EINVAL - Invalid segment usage number.
377 int nilfs_sufile_get_segment_usage(struct inode
*sufile
, __u64 segnum
,
378 struct nilfs_segment_usage
**sup
,
379 struct buffer_head
**bhp
)
381 struct buffer_head
*bh
;
382 struct nilfs_segment_usage
*su
;
386 /* segnum is 0 origin */
387 if (segnum
>= nilfs_sufile_get_nsegments(sufile
))
389 down_write(&NILFS_MDT(sufile
)->mi_sem
);
390 ret
= nilfs_sufile_get_segment_usage_block(sufile
, segnum
, 1, &bh
);
393 kaddr
= kmap(bh
->b_page
);
394 su
= nilfs_sufile_block_get_segment_usage(sufile
, segnum
, bh
, kaddr
);
395 if (nilfs_segment_usage_error(su
)) {
407 up_write(&NILFS_MDT(sufile
)->mi_sem
);
412 * nilfs_sufile_put_segment_usage - put a segment usage
413 * @sufile: inode of segment usage file
414 * @segnum: segment number
417 * Description: nilfs_sufile_put_segment_usage() releases the segment usage
418 * specified by @segnum. @bh must be the buffer head which have been returned
419 * by a previous call to nilfs_sufile_get_segment_usage() with @segnum.
421 void nilfs_sufile_put_segment_usage(struct inode
*sufile
, __u64 segnum
,
422 struct buffer_head
*bh
)
429 * nilfs_sufile_get_stat - get segment usage statistics
430 * @sufile: inode of segment usage file
431 * @stat: pointer to a structure of segment usage statistics
433 * Description: nilfs_sufile_get_stat() returns information about segment
436 * Return Value: On success, 0 is returned, and segment usage information is
437 * stored in the place pointed by @stat. On error, one of the following
438 * negative error codes is returned.
442 * %-ENOMEM - Insufficient amount of memory available.
444 int nilfs_sufile_get_stat(struct inode
*sufile
, struct nilfs_sustat
*sustat
)
446 struct buffer_head
*header_bh
;
447 struct nilfs_sufile_header
*header
;
448 struct the_nilfs
*nilfs
= NILFS_MDT(sufile
)->mi_nilfs
;
452 down_read(&NILFS_MDT(sufile
)->mi_sem
);
454 ret
= nilfs_sufile_get_header_block(sufile
, &header_bh
);
458 kaddr
= kmap_atomic(header_bh
->b_page
, KM_USER0
);
459 header
= nilfs_sufile_block_get_header(sufile
, header_bh
, kaddr
);
460 sustat
->ss_nsegs
= nilfs_sufile_get_nsegments(sufile
);
461 sustat
->ss_ncleansegs
= le64_to_cpu(header
->sh_ncleansegs
);
462 sustat
->ss_ndirtysegs
= le64_to_cpu(header
->sh_ndirtysegs
);
463 sustat
->ss_ctime
= nilfs
->ns_ctime
;
464 sustat
->ss_nongc_ctime
= nilfs
->ns_nongc_ctime
;
465 spin_lock(&nilfs
->ns_last_segment_lock
);
466 sustat
->ss_prot_seq
= nilfs
->ns_prot_seq
;
467 spin_unlock(&nilfs
->ns_last_segment_lock
);
468 kunmap_atomic(kaddr
, KM_USER0
);
472 up_read(&NILFS_MDT(sufile
)->mi_sem
);
477 * nilfs_sufile_get_ncleansegs - get the number of clean segments
478 * @sufile: inode of segment usage file
479 * @nsegsp: pointer to the number of clean segments
481 * Description: nilfs_sufile_get_ncleansegs() acquires the number of clean
484 * Return Value: On success, 0 is returned and the number of clean segments is
485 * stored in the place pointed by @nsegsp. On error, one of the following
486 * negative error codes is returned.
490 * %-ENOMEM - Insufficient amount of memory available.
492 int nilfs_sufile_get_ncleansegs(struct inode
*sufile
, unsigned long *nsegsp
)
494 struct nilfs_sustat sustat
;
497 ret
= nilfs_sufile_get_stat(sufile
, &sustat
);
499 *nsegsp
= sustat
.ss_ncleansegs
;
504 * nilfs_sufile_set_error - mark a segment as erroneous
505 * @sufile: inode of segment usage file
506 * @segnum: segment number
508 * Description: nilfs_sufile_set_error() marks the segment specified by
509 * @segnum as erroneous. The error segment will never be used again.
511 * Return Value: On success, 0 is returned. On error, one of the following
512 * negative error codes is returned.
516 * %-ENOMEM - Insufficient amount of memory available.
518 * %-EINVAL - Invalid segment usage number.
520 int nilfs_sufile_set_error(struct inode
*sufile
, __u64 segnum
)
522 struct buffer_head
*header_bh
, *su_bh
;
523 struct nilfs_segment_usage
*su
;
524 struct nilfs_sufile_header
*header
;
528 if (unlikely(segnum
>= nilfs_sufile_get_nsegments(sufile
))) {
529 printk(KERN_WARNING
"%s: invalid segment number: %llu\n",
530 __func__
, (unsigned long long)segnum
);
533 down_write(&NILFS_MDT(sufile
)->mi_sem
);
535 ret
= nilfs_sufile_get_header_block(sufile
, &header_bh
);
538 ret
= nilfs_sufile_get_segment_usage_block(sufile
, segnum
, 0, &su_bh
);
542 kaddr
= kmap_atomic(su_bh
->b_page
, KM_USER0
);
543 su
= nilfs_sufile_block_get_segment_usage(sufile
, segnum
, su_bh
, kaddr
);
544 if (nilfs_segment_usage_error(su
)) {
545 kunmap_atomic(kaddr
, KM_USER0
);
550 nilfs_segment_usage_set_error(su
);
551 kunmap_atomic(kaddr
, KM_USER0
);
554 kaddr
= kmap_atomic(header_bh
->b_page
, KM_USER0
);
555 header
= nilfs_sufile_block_get_header(sufile
, header_bh
, kaddr
);
556 le64_add_cpu(&header
->sh_ndirtysegs
, -1);
557 kunmap_atomic(kaddr
, KM_USER0
);
558 nilfs_mdt_mark_buffer_dirty(header_bh
);
559 nilfs_mdt_mark_buffer_dirty(su_bh
);
560 nilfs_mdt_mark_dirty(sufile
);
567 up_write(&NILFS_MDT(sufile
)->mi_sem
);
572 * nilfs_sufile_get_suinfo -
573 * @sufile: inode of segment usage file
574 * @segnum: segment number to start looking
575 * @si: array of suinfo
576 * @nsi: size of suinfo array
580 * Return Value: On success, 0 is returned and .... On error, one of the
581 * following negative error codes is returned.
585 * %-ENOMEM - Insufficient amount of memory available.
587 ssize_t
nilfs_sufile_get_suinfo(struct inode
*sufile
, __u64 segnum
,
588 struct nilfs_suinfo
*si
, size_t nsi
)
590 struct buffer_head
*su_bh
;
591 struct nilfs_segment_usage
*su
;
592 size_t susz
= NILFS_MDT(sufile
)->mi_entry_size
;
593 struct the_nilfs
*nilfs
= NILFS_MDT(sufile
)->mi_nilfs
;
595 unsigned long nsegs
, segusages_per_block
;
599 down_read(&NILFS_MDT(sufile
)->mi_sem
);
601 segusages_per_block
= nilfs_sufile_segment_usages_per_block(sufile
);
602 nsegs
= min_t(unsigned long,
603 nilfs_sufile_get_nsegments(sufile
) - segnum
,
605 for (i
= 0; i
< nsegs
; i
+= n
, segnum
+= n
) {
606 n
= min_t(unsigned long,
607 segusages_per_block
-
608 nilfs_sufile_get_offset(sufile
, segnum
),
610 ret
= nilfs_sufile_get_segment_usage_block(sufile
, segnum
, 0,
616 memset(&si
[i
], 0, sizeof(struct nilfs_suinfo
) * n
);
620 kaddr
= kmap_atomic(su_bh
->b_page
, KM_USER0
);
621 su
= nilfs_sufile_block_get_segment_usage(
622 sufile
, segnum
, su_bh
, kaddr
);
623 for (j
= 0; j
< n
; j
++, su
= (void *)su
+ susz
) {
624 si
[i
+ j
].sui_lastmod
= le64_to_cpu(su
->su_lastmod
);
625 si
[i
+ j
].sui_nblocks
= le32_to_cpu(su
->su_nblocks
);
626 si
[i
+ j
].sui_flags
= le32_to_cpu(su
->su_flags
) &
627 ~(1UL << NILFS_SEGMENT_USAGE_ACTIVE
);
628 if (nilfs_segment_is_active(nilfs
, segnum
+ i
+ j
))
629 si
[i
+ j
].sui_flags
|=
630 (1UL << NILFS_SEGMENT_USAGE_ACTIVE
);
632 kunmap_atomic(kaddr
, KM_USER0
);
638 up_read(&NILFS_MDT(sufile
)->mi_sem
);