Commit | Line | Data |
---|---|---|
64b5a32e RK |
1 | /* |
2 | * segbuf.c - NILFS segment buffer | |
3 | * | |
4 | * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
19 | * | |
20 | * Written by Ryusuke Konishi <ryusuke@osrg.net> | |
21 | * | |
22 | */ | |
23 | ||
24 | #include <linux/buffer_head.h> | |
25 | #include <linux/writeback.h> | |
26 | #include <linux/crc32.h> | |
9c965bac | 27 | #include <linux/backing-dev.h> |
64b5a32e RK |
28 | #include "page.h" |
29 | #include "segbuf.h" | |
64b5a32e RK |
30 | |
31 | ||
9c965bac RK |
32 | struct nilfs_write_info { |
33 | struct the_nilfs *nilfs; | |
34 | struct bio *bio; | |
35 | int start, end; /* The region to be submitted */ | |
36 | int rest_blocks; | |
37 | int max_pages; | |
38 | int nr_vecs; | |
39 | sector_t blocknr; | |
40 | }; | |
41 | ||
42 | ||
d1c6b72a RK |
43 | static int nilfs_segbuf_write(struct nilfs_segment_buffer *segbuf, |
44 | struct the_nilfs *nilfs); | |
45 | static int nilfs_segbuf_wait(struct nilfs_segment_buffer *segbuf); | |
46 | ||
47 | ||
64b5a32e RK |
48 | static struct kmem_cache *nilfs_segbuf_cachep; |
49 | ||
50 | static void nilfs_segbuf_init_once(void *obj) | |
51 | { | |
52 | memset(obj, 0, sizeof(struct nilfs_segment_buffer)); | |
53 | } | |
54 | ||
55 | int __init nilfs_init_segbuf_cache(void) | |
56 | { | |
57 | nilfs_segbuf_cachep = | |
58 | kmem_cache_create("nilfs2_segbuf_cache", | |
59 | sizeof(struct nilfs_segment_buffer), | |
60 | 0, SLAB_RECLAIM_ACCOUNT, | |
61 | nilfs_segbuf_init_once); | |
62 | ||
63 | return (nilfs_segbuf_cachep == NULL) ? -ENOMEM : 0; | |
64 | } | |
65 | ||
66 | void nilfs_destroy_segbuf_cache(void) | |
67 | { | |
68 | kmem_cache_destroy(nilfs_segbuf_cachep); | |
69 | } | |
70 | ||
71 | struct nilfs_segment_buffer *nilfs_segbuf_new(struct super_block *sb) | |
72 | { | |
73 | struct nilfs_segment_buffer *segbuf; | |
74 | ||
75 | segbuf = kmem_cache_alloc(nilfs_segbuf_cachep, GFP_NOFS); | |
76 | if (unlikely(!segbuf)) | |
77 | return NULL; | |
78 | ||
79 | segbuf->sb_super = sb; | |
80 | INIT_LIST_HEAD(&segbuf->sb_list); | |
81 | INIT_LIST_HEAD(&segbuf->sb_segsum_buffers); | |
82 | INIT_LIST_HEAD(&segbuf->sb_payload_buffers); | |
9284ad2a RK |
83 | |
84 | init_completion(&segbuf->sb_bio_event); | |
85 | atomic_set(&segbuf->sb_err, 0); | |
86 | segbuf->sb_nbio = 0; | |
87 | ||
64b5a32e RK |
88 | return segbuf; |
89 | } | |
90 | ||
91 | void nilfs_segbuf_free(struct nilfs_segment_buffer *segbuf) | |
92 | { | |
64b5a32e RK |
93 | kmem_cache_free(nilfs_segbuf_cachep, segbuf); |
94 | } | |
95 | ||
cece5520 | 96 | void nilfs_segbuf_map(struct nilfs_segment_buffer *segbuf, __u64 segnum, |
64b5a32e RK |
97 | unsigned long offset, struct the_nilfs *nilfs) |
98 | { | |
64b5a32e RK |
99 | segbuf->sb_segnum = segnum; |
100 | nilfs_get_segment_range(nilfs, segnum, &segbuf->sb_fseg_start, | |
101 | &segbuf->sb_fseg_end); | |
102 | ||
103 | segbuf->sb_pseg_start = segbuf->sb_fseg_start + offset; | |
104 | segbuf->sb_rest_blocks = | |
105 | segbuf->sb_fseg_end - segbuf->sb_pseg_start + 1; | |
64b5a32e RK |
106 | } |
107 | ||
a694291a RK |
108 | /** |
109 | * nilfs_segbuf_map_cont - map a new log behind a given log | |
110 | * @segbuf: new segment buffer | |
111 | * @prev: segment buffer containing a log to be continued | |
112 | */ | |
113 | void nilfs_segbuf_map_cont(struct nilfs_segment_buffer *segbuf, | |
114 | struct nilfs_segment_buffer *prev) | |
115 | { | |
116 | segbuf->sb_segnum = prev->sb_segnum; | |
117 | segbuf->sb_fseg_start = prev->sb_fseg_start; | |
118 | segbuf->sb_fseg_end = prev->sb_fseg_end; | |
119 | segbuf->sb_pseg_start = prev->sb_pseg_start + prev->sb_sum.nblocks; | |
120 | segbuf->sb_rest_blocks = | |
121 | segbuf->sb_fseg_end - segbuf->sb_pseg_start + 1; | |
122 | } | |
123 | ||
64b5a32e RK |
124 | void nilfs_segbuf_set_next_segnum(struct nilfs_segment_buffer *segbuf, |
125 | __u64 nextnum, struct the_nilfs *nilfs) | |
126 | { | |
127 | segbuf->sb_nextnum = nextnum; | |
128 | segbuf->sb_sum.next = nilfs_get_segment_start_blocknr(nilfs, nextnum); | |
129 | } | |
130 | ||
131 | int nilfs_segbuf_extend_segsum(struct nilfs_segment_buffer *segbuf) | |
132 | { | |
133 | struct buffer_head *bh; | |
134 | ||
135 | bh = sb_getblk(segbuf->sb_super, | |
136 | segbuf->sb_pseg_start + segbuf->sb_sum.nsumblk); | |
137 | if (unlikely(!bh)) | |
138 | return -ENOMEM; | |
139 | ||
140 | nilfs_segbuf_add_segsum_buffer(segbuf, bh); | |
141 | return 0; | |
142 | } | |
143 | ||
144 | int nilfs_segbuf_extend_payload(struct nilfs_segment_buffer *segbuf, | |
145 | struct buffer_head **bhp) | |
146 | { | |
147 | struct buffer_head *bh; | |
148 | ||
149 | bh = sb_getblk(segbuf->sb_super, | |
150 | segbuf->sb_pseg_start + segbuf->sb_sum.nblocks); | |
151 | if (unlikely(!bh)) | |
152 | return -ENOMEM; | |
153 | ||
154 | nilfs_segbuf_add_payload_buffer(segbuf, bh); | |
155 | *bhp = bh; | |
156 | return 0; | |
157 | } | |
158 | ||
159 | int nilfs_segbuf_reset(struct nilfs_segment_buffer *segbuf, unsigned flags, | |
160 | time_t ctime) | |
161 | { | |
162 | int err; | |
163 | ||
164 | segbuf->sb_sum.nblocks = segbuf->sb_sum.nsumblk = 0; | |
165 | err = nilfs_segbuf_extend_segsum(segbuf); | |
166 | if (unlikely(err)) | |
167 | return err; | |
168 | ||
169 | segbuf->sb_sum.flags = flags; | |
170 | segbuf->sb_sum.sumbytes = sizeof(struct nilfs_segment_summary); | |
171 | segbuf->sb_sum.nfinfo = segbuf->sb_sum.nfileblk = 0; | |
172 | segbuf->sb_sum.ctime = ctime; | |
64b5a32e RK |
173 | return 0; |
174 | } | |
175 | ||
176 | /* | |
7a65004b | 177 | * Setup segment summary |
64b5a32e RK |
178 | */ |
179 | void nilfs_segbuf_fill_in_segsum(struct nilfs_segment_buffer *segbuf) | |
180 | { | |
181 | struct nilfs_segment_summary *raw_sum; | |
182 | struct buffer_head *bh_sum; | |
183 | ||
184 | bh_sum = list_entry(segbuf->sb_segsum_buffers.next, | |
185 | struct buffer_head, b_assoc_buffers); | |
186 | raw_sum = (struct nilfs_segment_summary *)bh_sum->b_data; | |
187 | ||
188 | raw_sum->ss_magic = cpu_to_le32(NILFS_SEGSUM_MAGIC); | |
189 | raw_sum->ss_bytes = cpu_to_le16(sizeof(*raw_sum)); | |
190 | raw_sum->ss_flags = cpu_to_le16(segbuf->sb_sum.flags); | |
191 | raw_sum->ss_seq = cpu_to_le64(segbuf->sb_sum.seg_seq); | |
192 | raw_sum->ss_create = cpu_to_le64(segbuf->sb_sum.ctime); | |
193 | raw_sum->ss_next = cpu_to_le64(segbuf->sb_sum.next); | |
194 | raw_sum->ss_nblocks = cpu_to_le32(segbuf->sb_sum.nblocks); | |
195 | raw_sum->ss_nfinfo = cpu_to_le32(segbuf->sb_sum.nfinfo); | |
196 | raw_sum->ss_sumbytes = cpu_to_le32(segbuf->sb_sum.sumbytes); | |
197 | raw_sum->ss_pad = 0; | |
198 | } | |
199 | ||
200 | /* | |
201 | * CRC calculation routines | |
202 | */ | |
203 | void nilfs_segbuf_fill_in_segsum_crc(struct nilfs_segment_buffer *segbuf, | |
204 | u32 seed) | |
205 | { | |
206 | struct buffer_head *bh; | |
207 | struct nilfs_segment_summary *raw_sum; | |
208 | unsigned long size, bytes = segbuf->sb_sum.sumbytes; | |
209 | u32 crc; | |
210 | ||
211 | bh = list_entry(segbuf->sb_segsum_buffers.next, struct buffer_head, | |
212 | b_assoc_buffers); | |
213 | ||
214 | raw_sum = (struct nilfs_segment_summary *)bh->b_data; | |
215 | size = min_t(unsigned long, bytes, bh->b_size); | |
216 | crc = crc32_le(seed, | |
217 | (unsigned char *)raw_sum + | |
218 | sizeof(raw_sum->ss_datasum) + sizeof(raw_sum->ss_sumsum), | |
219 | size - (sizeof(raw_sum->ss_datasum) + | |
220 | sizeof(raw_sum->ss_sumsum))); | |
221 | ||
222 | list_for_each_entry_continue(bh, &segbuf->sb_segsum_buffers, | |
223 | b_assoc_buffers) { | |
224 | bytes -= size; | |
225 | size = min_t(unsigned long, bytes, bh->b_size); | |
226 | crc = crc32_le(crc, bh->b_data, size); | |
227 | } | |
228 | raw_sum->ss_sumsum = cpu_to_le32(crc); | |
229 | } | |
230 | ||
231 | void nilfs_segbuf_fill_in_data_crc(struct nilfs_segment_buffer *segbuf, | |
232 | u32 seed) | |
233 | { | |
234 | struct buffer_head *bh; | |
235 | struct nilfs_segment_summary *raw_sum; | |
236 | void *kaddr; | |
237 | u32 crc; | |
238 | ||
239 | bh = list_entry(segbuf->sb_segsum_buffers.next, struct buffer_head, | |
240 | b_assoc_buffers); | |
241 | raw_sum = (struct nilfs_segment_summary *)bh->b_data; | |
242 | crc = crc32_le(seed, | |
243 | (unsigned char *)raw_sum + sizeof(raw_sum->ss_datasum), | |
244 | bh->b_size - sizeof(raw_sum->ss_datasum)); | |
245 | ||
246 | list_for_each_entry_continue(bh, &segbuf->sb_segsum_buffers, | |
247 | b_assoc_buffers) { | |
248 | crc = crc32_le(crc, bh->b_data, bh->b_size); | |
249 | } | |
250 | list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { | |
251 | kaddr = kmap_atomic(bh->b_page, KM_USER0); | |
252 | crc = crc32_le(crc, kaddr + bh_offset(bh), bh->b_size); | |
253 | kunmap_atomic(kaddr, KM_USER0); | |
254 | } | |
255 | raw_sum->ss_datasum = cpu_to_le32(crc); | |
256 | } | |
257 | ||
e29df395 | 258 | static void nilfs_release_buffers(struct list_head *list) |
64b5a32e RK |
259 | { |
260 | struct buffer_head *bh, *n; | |
261 | ||
262 | list_for_each_entry_safe(bh, n, list, b_assoc_buffers) { | |
263 | list_del_init(&bh->b_assoc_buffers); | |
264 | if (buffer_nilfs_allocated(bh)) { | |
265 | struct page *clone_page = bh->b_page; | |
266 | ||
267 | /* remove clone page */ | |
268 | brelse(bh); | |
269 | page_cache_release(clone_page); /* for each bh */ | |
270 | if (page_count(clone_page) <= 2) { | |
271 | lock_page(clone_page); | |
272 | nilfs_free_private_page(clone_page); | |
273 | } | |
274 | continue; | |
275 | } | |
276 | brelse(bh); | |
277 | } | |
278 | } | |
279 | ||
e29df395 RK |
280 | static void nilfs_segbuf_clear(struct nilfs_segment_buffer *segbuf) |
281 | { | |
282 | nilfs_release_buffers(&segbuf->sb_segsum_buffers); | |
283 | nilfs_release_buffers(&segbuf->sb_payload_buffers); | |
284 | } | |
285 | ||
286 | /* | |
287 | * Iterators for segment buffers | |
288 | */ | |
289 | void nilfs_clear_logs(struct list_head *logs) | |
290 | { | |
291 | struct nilfs_segment_buffer *segbuf; | |
292 | ||
293 | list_for_each_entry(segbuf, logs, sb_list) | |
294 | nilfs_segbuf_clear(segbuf); | |
295 | } | |
296 | ||
297 | void nilfs_truncate_logs(struct list_head *logs, | |
298 | struct nilfs_segment_buffer *last) | |
299 | { | |
300 | struct nilfs_segment_buffer *n, *segbuf; | |
301 | ||
302 | segbuf = list_prepare_entry(last, logs, sb_list); | |
303 | list_for_each_entry_safe_continue(segbuf, n, logs, sb_list) { | |
304 | list_del_init(&segbuf->sb_list); | |
305 | nilfs_segbuf_clear(segbuf); | |
306 | nilfs_segbuf_free(segbuf); | |
307 | } | |
308 | } | |
309 | ||
d1c6b72a RK |
310 | int nilfs_write_logs(struct list_head *logs, struct the_nilfs *nilfs) |
311 | { | |
312 | struct nilfs_segment_buffer *segbuf; | |
313 | int ret = 0; | |
314 | ||
315 | list_for_each_entry(segbuf, logs, sb_list) { | |
316 | ret = nilfs_segbuf_write(segbuf, nilfs); | |
317 | if (ret) | |
318 | break; | |
319 | } | |
320 | return ret; | |
321 | } | |
322 | ||
e29df395 RK |
323 | int nilfs_wait_on_logs(struct list_head *logs) |
324 | { | |
325 | struct nilfs_segment_buffer *segbuf; | |
326 | int err; | |
327 | ||
328 | list_for_each_entry(segbuf, logs, sb_list) { | |
329 | err = nilfs_segbuf_wait(segbuf); | |
330 | if (err) | |
331 | return err; | |
332 | } | |
333 | return 0; | |
334 | } | |
335 | ||
64b5a32e RK |
336 | /* |
337 | * BIO operations | |
338 | */ | |
339 | static void nilfs_end_bio_write(struct bio *bio, int err) | |
340 | { | |
341 | const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
9284ad2a | 342 | struct nilfs_segment_buffer *segbuf = bio->bi_private; |
64b5a32e RK |
343 | |
344 | if (err == -EOPNOTSUPP) { | |
345 | set_bit(BIO_EOPNOTSUPP, &bio->bi_flags); | |
346 | bio_put(bio); | |
347 | /* to be detected by submit_seg_bio() */ | |
348 | } | |
349 | ||
350 | if (!uptodate) | |
9284ad2a | 351 | atomic_inc(&segbuf->sb_err); |
64b5a32e RK |
352 | |
353 | bio_put(bio); | |
9284ad2a | 354 | complete(&segbuf->sb_bio_event); |
64b5a32e RK |
355 | } |
356 | ||
9284ad2a RK |
357 | static int nilfs_segbuf_submit_bio(struct nilfs_segment_buffer *segbuf, |
358 | struct nilfs_write_info *wi, int mode) | |
64b5a32e RK |
359 | { |
360 | struct bio *bio = wi->bio; | |
361 | int err; | |
362 | ||
9c965bac | 363 | if (segbuf->sb_nbio > 0 && bdi_write_congested(wi->nilfs->ns_bdi)) { |
9284ad2a RK |
364 | wait_for_completion(&segbuf->sb_bio_event); |
365 | segbuf->sb_nbio--; | |
366 | if (unlikely(atomic_read(&segbuf->sb_err))) { | |
64b5a32e RK |
367 | bio_put(bio); |
368 | err = -EIO; | |
369 | goto failed; | |
370 | } | |
371 | } | |
372 | ||
373 | bio->bi_end_io = nilfs_end_bio_write; | |
9284ad2a | 374 | bio->bi_private = segbuf; |
64b5a32e RK |
375 | bio_get(bio); |
376 | submit_bio(mode, bio); | |
377 | if (bio_flagged(bio, BIO_EOPNOTSUPP)) { | |
378 | bio_put(bio); | |
379 | err = -EOPNOTSUPP; | |
380 | goto failed; | |
381 | } | |
9284ad2a | 382 | segbuf->sb_nbio++; |
64b5a32e RK |
383 | bio_put(bio); |
384 | ||
385 | wi->bio = NULL; | |
386 | wi->rest_blocks -= wi->end - wi->start; | |
387 | wi->nr_vecs = min(wi->max_pages, wi->rest_blocks); | |
388 | wi->start = wi->end; | |
389 | return 0; | |
390 | ||
391 | failed: | |
392 | wi->bio = NULL; | |
393 | return err; | |
394 | } | |
395 | ||
396 | /** | |
9c965bac RK |
397 | * nilfs_alloc_seg_bio - allocate a new bio for writing log |
398 | * @nilfs: nilfs object | |
399 | * @start: start block number of the bio | |
64b5a32e RK |
400 | * @nr_vecs: request size of page vector. |
401 | * | |
64b5a32e RK |
402 | * Return Value: On success, pointer to the struct bio is returned. |
403 | * On error, NULL is returned. | |
404 | */ | |
9c965bac | 405 | static struct bio *nilfs_alloc_seg_bio(struct the_nilfs *nilfs, sector_t start, |
64b5a32e RK |
406 | int nr_vecs) |
407 | { | |
408 | struct bio *bio; | |
409 | ||
c1b353f0 | 410 | bio = bio_alloc(GFP_NOIO, nr_vecs); |
64b5a32e RK |
411 | if (bio == NULL) { |
412 | while (!bio && (nr_vecs >>= 1)) | |
c1b353f0 | 413 | bio = bio_alloc(GFP_NOIO, nr_vecs); |
64b5a32e RK |
414 | } |
415 | if (likely(bio)) { | |
9c965bac RK |
416 | bio->bi_bdev = nilfs->ns_bdev; |
417 | bio->bi_sector = start << (nilfs->ns_blocksize_bits - 9); | |
64b5a32e RK |
418 | } |
419 | return bio; | |
420 | } | |
421 | ||
9c965bac RK |
422 | static void nilfs_segbuf_prepare_write(struct nilfs_segment_buffer *segbuf, |
423 | struct nilfs_write_info *wi) | |
64b5a32e RK |
424 | { |
425 | wi->bio = NULL; | |
426 | wi->rest_blocks = segbuf->sb_sum.nblocks; | |
9c965bac | 427 | wi->max_pages = bio_get_nr_vecs(wi->nilfs->ns_bdev); |
64b5a32e RK |
428 | wi->nr_vecs = min(wi->max_pages, wi->rest_blocks); |
429 | wi->start = wi->end = 0; | |
64b5a32e | 430 | wi->blocknr = segbuf->sb_pseg_start; |
64b5a32e RK |
431 | } |
432 | ||
9284ad2a RK |
433 | static int nilfs_segbuf_submit_bh(struct nilfs_segment_buffer *segbuf, |
434 | struct nilfs_write_info *wi, | |
435 | struct buffer_head *bh, int mode) | |
64b5a32e RK |
436 | { |
437 | int len, err; | |
438 | ||
439 | BUG_ON(wi->nr_vecs <= 0); | |
440 | repeat: | |
441 | if (!wi->bio) { | |
9c965bac | 442 | wi->bio = nilfs_alloc_seg_bio(wi->nilfs, wi->blocknr + wi->end, |
64b5a32e RK |
443 | wi->nr_vecs); |
444 | if (unlikely(!wi->bio)) | |
445 | return -ENOMEM; | |
446 | } | |
447 | ||
448 | len = bio_add_page(wi->bio, bh->b_page, bh->b_size, bh_offset(bh)); | |
449 | if (len == bh->b_size) { | |
450 | wi->end++; | |
451 | return 0; | |
452 | } | |
453 | /* bio is FULL */ | |
9284ad2a | 454 | err = nilfs_segbuf_submit_bio(segbuf, wi, mode); |
64b5a32e RK |
455 | /* never submit current bh */ |
456 | if (likely(!err)) | |
457 | goto repeat; | |
458 | return err; | |
459 | } | |
460 | ||
9c965bac RK |
461 | /** |
462 | * nilfs_segbuf_write - submit write requests of a log | |
463 | * @segbuf: buffer storing a log to be written | |
464 | * @nilfs: nilfs object | |
465 | * | |
466 | * Return Value: On Success, 0 is returned. On Error, one of the following | |
467 | * negative error code is returned. | |
468 | * | |
469 | * %-EIO - I/O error | |
470 | * | |
471 | * %-ENOMEM - Insufficient memory available. | |
472 | */ | |
6c477d44 RK |
473 | static int nilfs_segbuf_write(struct nilfs_segment_buffer *segbuf, |
474 | struct the_nilfs *nilfs) | |
64b5a32e | 475 | { |
9c965bac | 476 | struct nilfs_write_info wi; |
64b5a32e | 477 | struct buffer_head *bh; |
5f1586d0 | 478 | int res = 0, rw = WRITE; |
64b5a32e | 479 | |
9c965bac RK |
480 | wi.nilfs = nilfs; |
481 | nilfs_segbuf_prepare_write(segbuf, &wi); | |
482 | ||
64b5a32e | 483 | list_for_each_entry(bh, &segbuf->sb_segsum_buffers, b_assoc_buffers) { |
9c965bac | 484 | res = nilfs_segbuf_submit_bh(segbuf, &wi, bh, rw); |
64b5a32e RK |
485 | if (unlikely(res)) |
486 | goto failed_bio; | |
487 | } | |
488 | ||
489 | list_for_each_entry(bh, &segbuf->sb_payload_buffers, b_assoc_buffers) { | |
9c965bac | 490 | res = nilfs_segbuf_submit_bh(segbuf, &wi, bh, rw); |
64b5a32e RK |
491 | if (unlikely(res)) |
492 | goto failed_bio; | |
493 | } | |
494 | ||
9c965bac | 495 | if (wi.bio) { |
64b5a32e RK |
496 | /* |
497 | * Last BIO is always sent through the following | |
498 | * submission. | |
499 | */ | |
30bda0b8 | 500 | rw |= (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG); |
9c965bac | 501 | res = nilfs_segbuf_submit_bio(segbuf, &wi, rw); |
64b5a32e RK |
502 | } |
503 | ||
64b5a32e | 504 | failed_bio: |
5f1586d0 | 505 | return res; |
64b5a32e RK |
506 | } |
507 | ||
508 | /** | |
509 | * nilfs_segbuf_wait - wait for completion of requested BIOs | |
9284ad2a | 510 | * @segbuf: segment buffer |
64b5a32e RK |
511 | * |
512 | * Return Value: On Success, 0 is returned. On Error, one of the following | |
513 | * negative error code is returned. | |
514 | * | |
515 | * %-EIO - I/O error | |
516 | */ | |
6c477d44 | 517 | static int nilfs_segbuf_wait(struct nilfs_segment_buffer *segbuf) |
64b5a32e RK |
518 | { |
519 | int err = 0; | |
520 | ||
9284ad2a | 521 | if (!segbuf->sb_nbio) |
64b5a32e RK |
522 | return 0; |
523 | ||
524 | do { | |
9284ad2a RK |
525 | wait_for_completion(&segbuf->sb_bio_event); |
526 | } while (--segbuf->sb_nbio > 0); | |
64b5a32e | 527 | |
9284ad2a | 528 | if (unlikely(atomic_read(&segbuf->sb_err) > 0)) { |
64b5a32e RK |
529 | printk(KERN_ERR "NILFS: IO error writing segment\n"); |
530 | err = -EIO; | |
64b5a32e RK |
531 | } |
532 | return err; | |
533 | } |