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Commit | Line | Data |
---|---|---|
bd2d0210 TT |
1 | /* |
2 | * linux/fs/ext4/page-io.c | |
3 | * | |
4 | * This contains the new page_io functions for ext4 | |
5 | * | |
6 | * Written by Theodore Ts'o, 2010. | |
7 | */ | |
8 | ||
bd2d0210 TT |
9 | #include <linux/fs.h> |
10 | #include <linux/time.h> | |
11 | #include <linux/jbd2.h> | |
12 | #include <linux/highuid.h> | |
13 | #include <linux/pagemap.h> | |
14 | #include <linux/quotaops.h> | |
15 | #include <linux/string.h> | |
16 | #include <linux/buffer_head.h> | |
17 | #include <linux/writeback.h> | |
18 | #include <linux/pagevec.h> | |
19 | #include <linux/mpage.h> | |
20 | #include <linux/namei.h> | |
a27bb332 | 21 | #include <linux/aio.h> |
bd2d0210 TT |
22 | #include <linux/uio.h> |
23 | #include <linux/bio.h> | |
24 | #include <linux/workqueue.h> | |
25 | #include <linux/kernel.h> | |
26 | #include <linux/slab.h> | |
1ae48a63 | 27 | #include <linux/mm.h> |
bd2d0210 TT |
28 | |
29 | #include "ext4_jbd2.h" | |
30 | #include "xattr.h" | |
31 | #include "acl.h" | |
bd2d0210 | 32 | |
0058f965 | 33 | static struct kmem_cache *io_end_cachep; |
bd2d0210 | 34 | |
5dabfc78 | 35 | int __init ext4_init_pageio(void) |
bd2d0210 | 36 | { |
bd2d0210 | 37 | io_end_cachep = KMEM_CACHE(ext4_io_end, SLAB_RECLAIM_ACCOUNT); |
0058f965 | 38 | if (io_end_cachep == NULL) |
bd2d0210 | 39 | return -ENOMEM; |
bd2d0210 TT |
40 | return 0; |
41 | } | |
42 | ||
5dabfc78 | 43 | void ext4_exit_pageio(void) |
bd2d0210 TT |
44 | { |
45 | kmem_cache_destroy(io_end_cachep); | |
bd2d0210 TT |
46 | } |
47 | ||
b0857d30 JK |
48 | /* |
49 | * Print an buffer I/O error compatible with the fs/buffer.c. This | |
50 | * provides compatibility with dmesg scrapers that look for a specific | |
51 | * buffer I/O error message. We really need a unified error reporting | |
52 | * structure to userspace ala Digital Unix's uerf system, but it's | |
53 | * probably not going to happen in my lifetime, due to LKML politics... | |
54 | */ | |
55 | static void buffer_io_error(struct buffer_head *bh) | |
56 | { | |
57 | char b[BDEVNAME_SIZE]; | |
58 | printk(KERN_ERR "Buffer I/O error on device %s, logical block %llu\n", | |
59 | bdevname(bh->b_bdev, b), | |
60 | (unsigned long long)bh->b_blocknr); | |
61 | } | |
62 | ||
63 | static void ext4_finish_bio(struct bio *bio) | |
64 | { | |
65 | int i; | |
66 | int error = !test_bit(BIO_UPTODATE, &bio->bi_flags); | |
67 | ||
68 | for (i = 0; i < bio->bi_vcnt; i++) { | |
69 | struct bio_vec *bvec = &bio->bi_io_vec[i]; | |
70 | struct page *page = bvec->bv_page; | |
71 | struct buffer_head *bh, *head; | |
72 | unsigned bio_start = bvec->bv_offset; | |
73 | unsigned bio_end = bio_start + bvec->bv_len; | |
74 | unsigned under_io = 0; | |
75 | unsigned long flags; | |
76 | ||
77 | if (!page) | |
78 | continue; | |
79 | ||
80 | if (error) { | |
81 | SetPageError(page); | |
82 | set_bit(AS_EIO, &page->mapping->flags); | |
83 | } | |
84 | bh = head = page_buffers(page); | |
85 | /* | |
86 | * We check all buffers in the page under BH_Uptodate_Lock | |
87 | * to avoid races with other end io clearing async_write flags | |
88 | */ | |
89 | local_irq_save(flags); | |
90 | bit_spin_lock(BH_Uptodate_Lock, &head->b_state); | |
91 | do { | |
92 | if (bh_offset(bh) < bio_start || | |
93 | bh_offset(bh) + bh->b_size > bio_end) { | |
94 | if (buffer_async_write(bh)) | |
95 | under_io++; | |
96 | continue; | |
97 | } | |
98 | clear_buffer_async_write(bh); | |
99 | if (error) | |
100 | buffer_io_error(bh); | |
101 | } while ((bh = bh->b_this_page) != head); | |
102 | bit_spin_unlock(BH_Uptodate_Lock, &head->b_state); | |
103 | local_irq_restore(flags); | |
104 | if (!under_io) | |
105 | end_page_writeback(page); | |
106 | } | |
107 | } | |
108 | ||
97a851ed | 109 | static void ext4_release_io_end(ext4_io_end_t *io_end) |
bd2d0210 | 110 | { |
b0857d30 JK |
111 | struct bio *bio, *next_bio; |
112 | ||
97a851ed JK |
113 | BUG_ON(!list_empty(&io_end->list)); |
114 | BUG_ON(io_end->flag & EXT4_IO_END_UNWRITTEN); | |
6b523df4 | 115 | WARN_ON(io_end->handle); |
97a851ed JK |
116 | |
117 | if (atomic_dec_and_test(&EXT4_I(io_end->inode)->i_ioend_count)) | |
118 | wake_up_all(ext4_ioend_wq(io_end->inode)); | |
b0857d30 JK |
119 | |
120 | for (bio = io_end->bio; bio; bio = next_bio) { | |
121 | next_bio = bio->bi_private; | |
122 | ext4_finish_bio(bio); | |
123 | bio_put(bio); | |
124 | } | |
97a851ed JK |
125 | if (io_end->flag & EXT4_IO_END_DIRECT) |
126 | inode_dio_done(io_end->inode); | |
127 | if (io_end->iocb) | |
128 | aio_complete(io_end->iocb, io_end->result, 0); | |
129 | kmem_cache_free(io_end_cachep, io_end); | |
130 | } | |
131 | ||
132 | static void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end) | |
133 | { | |
134 | struct inode *inode = io_end->inode; | |
82e54229 | 135 | |
97a851ed JK |
136 | io_end->flag &= ~EXT4_IO_END_UNWRITTEN; |
137 | /* Wake up anyone waiting on unwritten extent conversion */ | |
138 | if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten)) | |
139 | wake_up_all(ext4_ioend_wq(inode)); | |
bd2d0210 TT |
140 | } |
141 | ||
a115f749 JK |
142 | /* |
143 | * Check a range of space and convert unwritten extents to written. Note that | |
144 | * we are protected from truncate touching same part of extent tree by the | |
145 | * fact that truncate code waits for all DIO to finish (thus exclusion from | |
146 | * direct IO is achieved) and also waits for PageWriteback bits. Thus we | |
147 | * cannot get to ext4_ext_truncate() before all IOs overlapping that range are | |
148 | * completed (happens from ext4_free_ioend()). | |
149 | */ | |
28a535f9 | 150 | static int ext4_end_io(ext4_io_end_t *io) |
bd2d0210 TT |
151 | { |
152 | struct inode *inode = io->inode; | |
153 | loff_t offset = io->offset; | |
154 | ssize_t size = io->size; | |
6b523df4 | 155 | handle_t *handle = io->handle; |
bd2d0210 TT |
156 | int ret = 0; |
157 | ||
158 | ext4_debug("ext4_end_io_nolock: io 0x%p from inode %lu,list->next 0x%p," | |
159 | "list->prev 0x%p\n", | |
160 | io, inode->i_ino, io->list.next, io->list.prev); | |
161 | ||
6b523df4 JK |
162 | io->handle = NULL; /* Following call will use up the handle */ |
163 | ret = ext4_convert_unwritten_extents(handle, inode, offset, size); | |
bd2d0210 | 164 | if (ret < 0) { |
b82e384c TT |
165 | ext4_msg(inode->i_sb, KERN_EMERG, |
166 | "failed to convert unwritten extents to written " | |
167 | "extents -- potential data loss! " | |
168 | "(inode %lu, offset %llu, size %zd, error %d)", | |
169 | inode->i_ino, offset, size, ret); | |
bd2d0210 | 170 | } |
97a851ed JK |
171 | ext4_clear_io_unwritten_flag(io); |
172 | ext4_release_io_end(io); | |
bd2d0210 TT |
173 | return ret; |
174 | } | |
175 | ||
2e8fa54e | 176 | static void dump_completed_IO(struct inode *inode, struct list_head *head) |
28a535f9 DM |
177 | { |
178 | #ifdef EXT4FS_DEBUG | |
179 | struct list_head *cur, *before, *after; | |
180 | ext4_io_end_t *io, *io0, *io1; | |
28a535f9 | 181 | |
2e8fa54e | 182 | if (list_empty(head)) |
28a535f9 | 183 | return; |
28a535f9 | 184 | |
2e8fa54e JK |
185 | ext4_debug("Dump inode %lu completed io list\n", inode->i_ino); |
186 | list_for_each_entry(io, head, list) { | |
28a535f9 DM |
187 | cur = &io->list; |
188 | before = cur->prev; | |
189 | io0 = container_of(before, ext4_io_end_t, list); | |
190 | after = cur->next; | |
191 | io1 = container_of(after, ext4_io_end_t, list); | |
192 | ||
193 | ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n", | |
194 | io, inode->i_ino, io0, io1); | |
195 | } | |
196 | #endif | |
197 | } | |
198 | ||
199 | /* Add the io_end to per-inode completed end_io list. */ | |
97a851ed | 200 | static void ext4_add_complete_io(ext4_io_end_t *io_end) |
bd2d0210 | 201 | { |
28a535f9 DM |
202 | struct ext4_inode_info *ei = EXT4_I(io_end->inode); |
203 | struct workqueue_struct *wq; | |
204 | unsigned long flags; | |
205 | ||
206 | BUG_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN)); | |
d73d5046 | 207 | spin_lock_irqsave(&ei->i_completed_io_lock, flags); |
2e8fa54e JK |
208 | if (io_end->handle) { |
209 | wq = EXT4_SB(io_end->inode->i_sb)->rsv_conversion_wq; | |
210 | if (list_empty(&ei->i_rsv_conversion_list)) | |
211 | queue_work(wq, &ei->i_rsv_conversion_work); | |
212 | list_add_tail(&io_end->list, &ei->i_rsv_conversion_list); | |
213 | } else { | |
214 | wq = EXT4_SB(io_end->inode->i_sb)->unrsv_conversion_wq; | |
215 | if (list_empty(&ei->i_unrsv_conversion_list)) | |
216 | queue_work(wq, &ei->i_unrsv_conversion_work); | |
217 | list_add_tail(&io_end->list, &ei->i_unrsv_conversion_list); | |
218 | } | |
28a535f9 DM |
219 | spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); |
220 | } | |
d73d5046 | 221 | |
2e8fa54e JK |
222 | static int ext4_do_flush_completed_IO(struct inode *inode, |
223 | struct list_head *head) | |
28a535f9 DM |
224 | { |
225 | ext4_io_end_t *io; | |
002bd7fa | 226 | struct list_head unwritten; |
28a535f9 DM |
227 | unsigned long flags; |
228 | struct ext4_inode_info *ei = EXT4_I(inode); | |
229 | int err, ret = 0; | |
230 | ||
28a535f9 | 231 | spin_lock_irqsave(&ei->i_completed_io_lock, flags); |
2e8fa54e JK |
232 | dump_completed_IO(inode, head); |
233 | list_replace_init(head, &unwritten); | |
28a535f9 DM |
234 | spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); |
235 | ||
236 | while (!list_empty(&unwritten)) { | |
237 | io = list_entry(unwritten.next, ext4_io_end_t, list); | |
238 | BUG_ON(!(io->flag & EXT4_IO_END_UNWRITTEN)); | |
239 | list_del_init(&io->list); | |
240 | ||
241 | err = ext4_end_io(io); | |
242 | if (unlikely(!ret && err)) | |
243 | ret = err; | |
28a535f9 DM |
244 | } |
245 | return ret; | |
246 | } | |
247 | ||
248 | /* | |
2e8fa54e | 249 | * work on completed IO, to convert unwritten extents to extents |
28a535f9 | 250 | */ |
2e8fa54e JK |
251 | void ext4_end_io_rsv_work(struct work_struct *work) |
252 | { | |
253 | struct ext4_inode_info *ei = container_of(work, struct ext4_inode_info, | |
254 | i_rsv_conversion_work); | |
255 | ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_rsv_conversion_list); | |
256 | } | |
257 | ||
258 | void ext4_end_io_unrsv_work(struct work_struct *work) | |
28a535f9 | 259 | { |
84c17543 | 260 | struct ext4_inode_info *ei = container_of(work, struct ext4_inode_info, |
2e8fa54e JK |
261 | i_unrsv_conversion_work); |
262 | ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_unrsv_conversion_list); | |
28a535f9 DM |
263 | } |
264 | ||
bd2d0210 TT |
265 | ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags) |
266 | { | |
b17b35ec | 267 | ext4_io_end_t *io = kmem_cache_zalloc(io_end_cachep, flags); |
bd2d0210 | 268 | if (io) { |
f7ad6d2e TT |
269 | atomic_inc(&EXT4_I(inode)->i_ioend_count); |
270 | io->inode = inode; | |
bd2d0210 | 271 | INIT_LIST_HEAD(&io->list); |
97a851ed | 272 | atomic_set(&io->count, 1); |
bd2d0210 TT |
273 | } |
274 | return io; | |
275 | } | |
276 | ||
97a851ed JK |
277 | void ext4_put_io_end_defer(ext4_io_end_t *io_end) |
278 | { | |
279 | if (atomic_dec_and_test(&io_end->count)) { | |
280 | if (!(io_end->flag & EXT4_IO_END_UNWRITTEN) || !io_end->size) { | |
281 | ext4_release_io_end(io_end); | |
282 | return; | |
283 | } | |
284 | ext4_add_complete_io(io_end); | |
285 | } | |
286 | } | |
287 | ||
288 | int ext4_put_io_end(ext4_io_end_t *io_end) | |
289 | { | |
290 | int err = 0; | |
291 | ||
292 | if (atomic_dec_and_test(&io_end->count)) { | |
293 | if (io_end->flag & EXT4_IO_END_UNWRITTEN) { | |
6b523df4 JK |
294 | err = ext4_convert_unwritten_extents(io_end->handle, |
295 | io_end->inode, io_end->offset, | |
296 | io_end->size); | |
297 | io_end->handle = NULL; | |
97a851ed JK |
298 | ext4_clear_io_unwritten_flag(io_end); |
299 | } | |
300 | ext4_release_io_end(io_end); | |
301 | } | |
302 | return err; | |
303 | } | |
304 | ||
305 | ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end) | |
306 | { | |
307 | atomic_inc(&io_end->count); | |
308 | return io_end; | |
309 | } | |
310 | ||
bd2d0210 TT |
311 | static void ext4_end_bio(struct bio *bio, int error) |
312 | { | |
313 | ext4_io_end_t *io_end = bio->bi_private; | |
d50bdd5a | 314 | sector_t bi_sector = bio->bi_sector; |
bd2d0210 TT |
315 | |
316 | BUG_ON(!io_end); | |
bd2d0210 TT |
317 | bio->bi_end_io = NULL; |
318 | if (test_bit(BIO_UPTODATE, &bio->bi_flags)) | |
319 | error = 0; | |
0058f965 | 320 | |
b0857d30 | 321 | if (io_end->flag & EXT4_IO_END_UNWRITTEN) { |
0058f965 | 322 | /* |
b0857d30 JK |
323 | * Link bio into list hanging from io_end. We have to do it |
324 | * atomically as bio completions can be racing against each | |
325 | * other. | |
0058f965 | 326 | */ |
b0857d30 JK |
327 | bio->bi_private = xchg(&io_end->bio, bio); |
328 | } else { | |
329 | ext4_finish_bio(bio); | |
330 | bio_put(bio); | |
bd2d0210 | 331 | } |
f7ad6d2e TT |
332 | |
333 | if (error) { | |
b0857d30 JK |
334 | struct inode *inode = io_end->inode; |
335 | ||
f7ad6d2e TT |
336 | ext4_warning(inode->i_sb, "I/O error writing to inode %lu " |
337 | "(offset %llu size %ld starting block %llu)", | |
338 | inode->i_ino, | |
339 | (unsigned long long) io_end->offset, | |
340 | (long) io_end->size, | |
341 | (unsigned long long) | |
d50bdd5a | 342 | bi_sector >> (inode->i_blkbits - 9)); |
f7ad6d2e | 343 | } |
97a851ed | 344 | ext4_put_io_end_defer(io_end); |
bd2d0210 TT |
345 | } |
346 | ||
347 | void ext4_io_submit(struct ext4_io_submit *io) | |
348 | { | |
349 | struct bio *bio = io->io_bio; | |
350 | ||
351 | if (bio) { | |
352 | bio_get(io->io_bio); | |
353 | submit_bio(io->io_op, io->io_bio); | |
354 | BUG_ON(bio_flagged(io->io_bio, BIO_EOPNOTSUPP)); | |
355 | bio_put(io->io_bio); | |
356 | } | |
7dc57615 | 357 | io->io_bio = NULL; |
97a851ed JK |
358 | } |
359 | ||
360 | void ext4_io_submit_init(struct ext4_io_submit *io, | |
361 | struct writeback_control *wbc) | |
362 | { | |
363 | io->io_op = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE); | |
364 | io->io_bio = NULL; | |
7dc57615 | 365 | io->io_end = NULL; |
bd2d0210 TT |
366 | } |
367 | ||
97a851ed JK |
368 | static int io_submit_init_bio(struct ext4_io_submit *io, |
369 | struct buffer_head *bh) | |
bd2d0210 | 370 | { |
bd2d0210 TT |
371 | int nvecs = bio_get_nr_vecs(bh->b_bdev); |
372 | struct bio *bio; | |
373 | ||
275d3ba6 | 374 | bio = bio_alloc(GFP_NOIO, min(nvecs, BIO_MAX_PAGES)); |
a1d8d9a7 TT |
375 | if (!bio) |
376 | return -ENOMEM; | |
bd2d0210 TT |
377 | bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9); |
378 | bio->bi_bdev = bh->b_bdev; | |
bd2d0210 | 379 | bio->bi_end_io = ext4_end_bio; |
97a851ed | 380 | bio->bi_private = ext4_get_io_end(io->io_end); |
bd2d0210 | 381 | io->io_bio = bio; |
bd2d0210 TT |
382 | io->io_next_block = bh->b_blocknr; |
383 | return 0; | |
384 | } | |
385 | ||
386 | static int io_submit_add_bh(struct ext4_io_submit *io, | |
bd2d0210 | 387 | struct inode *inode, |
bd2d0210 TT |
388 | struct buffer_head *bh) |
389 | { | |
bd2d0210 TT |
390 | int ret; |
391 | ||
bd2d0210 TT |
392 | if (io->io_bio && bh->b_blocknr != io->io_next_block) { |
393 | submit_and_retry: | |
394 | ext4_io_submit(io); | |
395 | } | |
396 | if (io->io_bio == NULL) { | |
97a851ed | 397 | ret = io_submit_init_bio(io, bh); |
bd2d0210 TT |
398 | if (ret) |
399 | return ret; | |
400 | } | |
97a851ed JK |
401 | ret = bio_add_page(io->io_bio, bh->b_page, bh->b_size, bh_offset(bh)); |
402 | if (ret != bh->b_size) | |
403 | goto submit_and_retry; | |
bd2d0210 | 404 | io->io_next_block++; |
bd2d0210 TT |
405 | return 0; |
406 | } | |
407 | ||
408 | int ext4_bio_write_page(struct ext4_io_submit *io, | |
409 | struct page *page, | |
410 | int len, | |
411 | struct writeback_control *wbc) | |
412 | { | |
413 | struct inode *inode = page->mapping->host; | |
0058f965 | 414 | unsigned block_start, blocksize; |
bd2d0210 TT |
415 | struct buffer_head *bh, *head; |
416 | int ret = 0; | |
0058f965 | 417 | int nr_submitted = 0; |
bd2d0210 TT |
418 | |
419 | blocksize = 1 << inode->i_blkbits; | |
420 | ||
d50bdd5a | 421 | BUG_ON(!PageLocked(page)); |
bd2d0210 | 422 | BUG_ON(PageWriteback(page)); |
bd2d0210 | 423 | |
a54aa761 TT |
424 | set_page_writeback(page); |
425 | ClearPageError(page); | |
bd2d0210 | 426 | |
0058f965 JK |
427 | /* |
428 | * In the first loop we prepare and mark buffers to submit. We have to | |
429 | * mark all buffers in the page before submitting so that | |
430 | * end_page_writeback() cannot be called from ext4_bio_end_io() when IO | |
431 | * on the first buffer finishes and we are still working on submitting | |
432 | * the second buffer. | |
433 | */ | |
434 | bh = head = page_buffers(page); | |
435 | do { | |
436 | block_start = bh_offset(bh); | |
bd2d0210 | 437 | if (block_start >= len) { |
5a0dc736 YY |
438 | /* |
439 | * Comments copied from block_write_full_page_endio: | |
440 | * | |
441 | * The page straddles i_size. It must be zeroed out on | |
442 | * each and every writepage invocation because it may | |
443 | * be mmapped. "A file is mapped in multiples of the | |
444 | * page size. For a file that is not a multiple of | |
445 | * the page size, the remaining memory is zeroed when | |
446 | * mapped, and writes to that region are not written | |
447 | * out to the file." | |
448 | */ | |
0058f965 JK |
449 | zero_user_segment(page, block_start, |
450 | block_start + blocksize); | |
bd2d0210 TT |
451 | clear_buffer_dirty(bh); |
452 | set_buffer_uptodate(bh); | |
453 | continue; | |
454 | } | |
8a850c3f JK |
455 | if (!buffer_dirty(bh) || buffer_delay(bh) || |
456 | !buffer_mapped(bh) || buffer_unwritten(bh)) { | |
457 | /* A hole? We can safely clear the dirty bit */ | |
458 | if (!buffer_mapped(bh)) | |
459 | clear_buffer_dirty(bh); | |
460 | if (io->io_bio) | |
461 | ext4_io_submit(io); | |
462 | continue; | |
463 | } | |
0058f965 JK |
464 | if (buffer_new(bh)) { |
465 | clear_buffer_new(bh); | |
466 | unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr); | |
467 | } | |
468 | set_buffer_async_write(bh); | |
469 | } while ((bh = bh->b_this_page) != head); | |
470 | ||
471 | /* Now submit buffers to write */ | |
472 | bh = head = page_buffers(page); | |
473 | do { | |
474 | if (!buffer_async_write(bh)) | |
475 | continue; | |
97a851ed | 476 | ret = io_submit_add_bh(io, inode, bh); |
bd2d0210 TT |
477 | if (ret) { |
478 | /* | |
479 | * We only get here on ENOMEM. Not much else | |
480 | * we can do but mark the page as dirty, and | |
481 | * better luck next time. | |
482 | */ | |
1ae48a63 | 483 | redirty_page_for_writepage(wbc, page); |
bd2d0210 TT |
484 | break; |
485 | } | |
0058f965 | 486 | nr_submitted++; |
1ae48a63 | 487 | clear_buffer_dirty(bh); |
0058f965 JK |
488 | } while ((bh = bh->b_this_page) != head); |
489 | ||
490 | /* Error stopped previous loop? Clean up buffers... */ | |
491 | if (ret) { | |
492 | do { | |
493 | clear_buffer_async_write(bh); | |
494 | bh = bh->b_this_page; | |
495 | } while (bh != head); | |
bd2d0210 TT |
496 | } |
497 | unlock_page(page); | |
0058f965 JK |
498 | /* Nothing submitted - we have to end page writeback */ |
499 | if (!nr_submitted) | |
500 | end_page_writeback(page); | |
bd2d0210 TT |
501 | return ret; |
502 | } |