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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> | |
bd2d0210 TT |
11 | #include <linux/highuid.h> |
12 | #include <linux/pagemap.h> | |
13 | #include <linux/quotaops.h> | |
14 | #include <linux/string.h> | |
15 | #include <linux/buffer_head.h> | |
16 | #include <linux/writeback.h> | |
17 | #include <linux/pagevec.h> | |
18 | #include <linux/mpage.h> | |
19 | #include <linux/namei.h> | |
20 | #include <linux/uio.h> | |
21 | #include <linux/bio.h> | |
22 | #include <linux/workqueue.h> | |
23 | #include <linux/kernel.h> | |
24 | #include <linux/slab.h> | |
1ae48a63 | 25 | #include <linux/mm.h> |
bd2d0210 TT |
26 | |
27 | #include "ext4_jbd2.h" | |
28 | #include "xattr.h" | |
29 | #include "acl.h" | |
bd2d0210 | 30 | |
0058f965 | 31 | static struct kmem_cache *io_end_cachep; |
bd2d0210 | 32 | |
5dabfc78 | 33 | int __init ext4_init_pageio(void) |
bd2d0210 | 34 | { |
bd2d0210 | 35 | io_end_cachep = KMEM_CACHE(ext4_io_end, SLAB_RECLAIM_ACCOUNT); |
0058f965 | 36 | if (io_end_cachep == NULL) |
bd2d0210 | 37 | return -ENOMEM; |
bd2d0210 TT |
38 | return 0; |
39 | } | |
40 | ||
5dabfc78 | 41 | void ext4_exit_pageio(void) |
bd2d0210 TT |
42 | { |
43 | kmem_cache_destroy(io_end_cachep); | |
bd2d0210 TT |
44 | } |
45 | ||
b0857d30 JK |
46 | /* |
47 | * Print an buffer I/O error compatible with the fs/buffer.c. This | |
48 | * provides compatibility with dmesg scrapers that look for a specific | |
49 | * buffer I/O error message. We really need a unified error reporting | |
50 | * structure to userspace ala Digital Unix's uerf system, but it's | |
51 | * probably not going to happen in my lifetime, due to LKML politics... | |
52 | */ | |
53 | static void buffer_io_error(struct buffer_head *bh) | |
54 | { | |
55 | char b[BDEVNAME_SIZE]; | |
e8974c39 | 56 | printk_ratelimited(KERN_ERR "Buffer I/O error on device %s, logical block %llu\n", |
b0857d30 JK |
57 | bdevname(bh->b_bdev, b), |
58 | (unsigned long long)bh->b_blocknr); | |
59 | } | |
60 | ||
61 | static void ext4_finish_bio(struct bio *bio) | |
62 | { | |
63 | int i; | |
64 | int error = !test_bit(BIO_UPTODATE, &bio->bi_flags); | |
2c30c71b | 65 | struct bio_vec *bvec; |
b0857d30 | 66 | |
2c30c71b | 67 | bio_for_each_segment_all(bvec, bio, i) { |
b0857d30 | 68 | struct page *page = bvec->bv_page; |
2058f83a MH |
69 | #ifdef CONFIG_EXT4_FS_ENCRYPTION |
70 | struct page *data_page = NULL; | |
71 | struct ext4_crypto_ctx *ctx = NULL; | |
72 | #endif | |
b0857d30 JK |
73 | struct buffer_head *bh, *head; |
74 | unsigned bio_start = bvec->bv_offset; | |
75 | unsigned bio_end = bio_start + bvec->bv_len; | |
76 | unsigned under_io = 0; | |
77 | unsigned long flags; | |
78 | ||
79 | if (!page) | |
80 | continue; | |
81 | ||
2058f83a MH |
82 | #ifdef CONFIG_EXT4_FS_ENCRYPTION |
83 | if (!page->mapping) { | |
84 | /* The bounce data pages are unmapped. */ | |
85 | data_page = page; | |
86 | ctx = (struct ext4_crypto_ctx *)page_private(data_page); | |
614def70 | 87 | page = ctx->w.control_page; |
2058f83a MH |
88 | } |
89 | #endif | |
90 | ||
b0857d30 JK |
91 | if (error) { |
92 | SetPageError(page); | |
93 | set_bit(AS_EIO, &page->mapping->flags); | |
94 | } | |
95 | bh = head = page_buffers(page); | |
96 | /* | |
97 | * We check all buffers in the page under BH_Uptodate_Lock | |
98 | * to avoid races with other end io clearing async_write flags | |
99 | */ | |
100 | local_irq_save(flags); | |
101 | bit_spin_lock(BH_Uptodate_Lock, &head->b_state); | |
102 | do { | |
103 | if (bh_offset(bh) < bio_start || | |
104 | bh_offset(bh) + bh->b_size > bio_end) { | |
105 | if (buffer_async_write(bh)) | |
106 | under_io++; | |
107 | continue; | |
108 | } | |
109 | clear_buffer_async_write(bh); | |
110 | if (error) | |
111 | buffer_io_error(bh); | |
112 | } while ((bh = bh->b_this_page) != head); | |
113 | bit_spin_unlock(BH_Uptodate_Lock, &head->b_state); | |
114 | local_irq_restore(flags); | |
2058f83a MH |
115 | if (!under_io) { |
116 | #ifdef CONFIG_EXT4_FS_ENCRYPTION | |
117 | if (ctx) | |
118 | ext4_restore_control_page(data_page); | |
119 | #endif | |
b0857d30 | 120 | end_page_writeback(page); |
2058f83a | 121 | } |
b0857d30 JK |
122 | } |
123 | } | |
124 | ||
97a851ed | 125 | static void ext4_release_io_end(ext4_io_end_t *io_end) |
bd2d0210 | 126 | { |
b0857d30 JK |
127 | struct bio *bio, *next_bio; |
128 | ||
97a851ed JK |
129 | BUG_ON(!list_empty(&io_end->list)); |
130 | BUG_ON(io_end->flag & EXT4_IO_END_UNWRITTEN); | |
6b523df4 | 131 | WARN_ON(io_end->handle); |
97a851ed JK |
132 | |
133 | if (atomic_dec_and_test(&EXT4_I(io_end->inode)->i_ioend_count)) | |
134 | wake_up_all(ext4_ioend_wq(io_end->inode)); | |
b0857d30 JK |
135 | |
136 | for (bio = io_end->bio; bio; bio = next_bio) { | |
137 | next_bio = bio->bi_private; | |
138 | ext4_finish_bio(bio); | |
139 | bio_put(bio); | |
140 | } | |
97a851ed JK |
141 | kmem_cache_free(io_end_cachep, io_end); |
142 | } | |
143 | ||
144 | static void ext4_clear_io_unwritten_flag(ext4_io_end_t *io_end) | |
145 | { | |
146 | struct inode *inode = io_end->inode; | |
82e54229 | 147 | |
97a851ed JK |
148 | io_end->flag &= ~EXT4_IO_END_UNWRITTEN; |
149 | /* Wake up anyone waiting on unwritten extent conversion */ | |
150 | if (atomic_dec_and_test(&EXT4_I(inode)->i_unwritten)) | |
151 | wake_up_all(ext4_ioend_wq(inode)); | |
bd2d0210 TT |
152 | } |
153 | ||
a115f749 JK |
154 | /* |
155 | * Check a range of space and convert unwritten extents to written. Note that | |
156 | * we are protected from truncate touching same part of extent tree by the | |
157 | * fact that truncate code waits for all DIO to finish (thus exclusion from | |
158 | * direct IO is achieved) and also waits for PageWriteback bits. Thus we | |
159 | * cannot get to ext4_ext_truncate() before all IOs overlapping that range are | |
160 | * completed (happens from ext4_free_ioend()). | |
161 | */ | |
28a535f9 | 162 | static int ext4_end_io(ext4_io_end_t *io) |
bd2d0210 TT |
163 | { |
164 | struct inode *inode = io->inode; | |
165 | loff_t offset = io->offset; | |
166 | ssize_t size = io->size; | |
6b523df4 | 167 | handle_t *handle = io->handle; |
bd2d0210 TT |
168 | int ret = 0; |
169 | ||
170 | ext4_debug("ext4_end_io_nolock: io 0x%p from inode %lu,list->next 0x%p," | |
171 | "list->prev 0x%p\n", | |
172 | io, inode->i_ino, io->list.next, io->list.prev); | |
173 | ||
6b523df4 JK |
174 | io->handle = NULL; /* Following call will use up the handle */ |
175 | ret = ext4_convert_unwritten_extents(handle, inode, offset, size); | |
bd2d0210 | 176 | if (ret < 0) { |
b82e384c TT |
177 | ext4_msg(inode->i_sb, KERN_EMERG, |
178 | "failed to convert unwritten extents to written " | |
179 | "extents -- potential data loss! " | |
180 | "(inode %lu, offset %llu, size %zd, error %d)", | |
181 | inode->i_ino, offset, size, ret); | |
bd2d0210 | 182 | } |
97a851ed JK |
183 | ext4_clear_io_unwritten_flag(io); |
184 | ext4_release_io_end(io); | |
bd2d0210 TT |
185 | return ret; |
186 | } | |
187 | ||
2e8fa54e | 188 | static void dump_completed_IO(struct inode *inode, struct list_head *head) |
28a535f9 DM |
189 | { |
190 | #ifdef EXT4FS_DEBUG | |
191 | struct list_head *cur, *before, *after; | |
192 | ext4_io_end_t *io, *io0, *io1; | |
28a535f9 | 193 | |
2e8fa54e | 194 | if (list_empty(head)) |
28a535f9 | 195 | return; |
28a535f9 | 196 | |
2e8fa54e JK |
197 | ext4_debug("Dump inode %lu completed io list\n", inode->i_ino); |
198 | list_for_each_entry(io, head, list) { | |
28a535f9 DM |
199 | cur = &io->list; |
200 | before = cur->prev; | |
201 | io0 = container_of(before, ext4_io_end_t, list); | |
202 | after = cur->next; | |
203 | io1 = container_of(after, ext4_io_end_t, list); | |
204 | ||
205 | ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n", | |
206 | io, inode->i_ino, io0, io1); | |
207 | } | |
208 | #endif | |
209 | } | |
210 | ||
211 | /* Add the io_end to per-inode completed end_io list. */ | |
97a851ed | 212 | static void ext4_add_complete_io(ext4_io_end_t *io_end) |
bd2d0210 | 213 | { |
28a535f9 | 214 | struct ext4_inode_info *ei = EXT4_I(io_end->inode); |
78371a45 | 215 | struct ext4_sb_info *sbi = EXT4_SB(io_end->inode->i_sb); |
28a535f9 DM |
216 | struct workqueue_struct *wq; |
217 | unsigned long flags; | |
218 | ||
7b7a8665 CH |
219 | /* Only reserved conversions from writeback should enter here */ |
220 | WARN_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN)); | |
78371a45 | 221 | WARN_ON(!io_end->handle && sbi->s_journal); |
d73d5046 | 222 | spin_lock_irqsave(&ei->i_completed_io_lock, flags); |
78371a45 | 223 | wq = sbi->rsv_conversion_wq; |
7b7a8665 CH |
224 | if (list_empty(&ei->i_rsv_conversion_list)) |
225 | queue_work(wq, &ei->i_rsv_conversion_work); | |
226 | list_add_tail(&io_end->list, &ei->i_rsv_conversion_list); | |
28a535f9 DM |
227 | spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); |
228 | } | |
d73d5046 | 229 | |
2e8fa54e JK |
230 | static int ext4_do_flush_completed_IO(struct inode *inode, |
231 | struct list_head *head) | |
28a535f9 DM |
232 | { |
233 | ext4_io_end_t *io; | |
002bd7fa | 234 | struct list_head unwritten; |
28a535f9 DM |
235 | unsigned long flags; |
236 | struct ext4_inode_info *ei = EXT4_I(inode); | |
237 | int err, ret = 0; | |
238 | ||
28a535f9 | 239 | spin_lock_irqsave(&ei->i_completed_io_lock, flags); |
2e8fa54e JK |
240 | dump_completed_IO(inode, head); |
241 | list_replace_init(head, &unwritten); | |
28a535f9 DM |
242 | spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); |
243 | ||
244 | while (!list_empty(&unwritten)) { | |
245 | io = list_entry(unwritten.next, ext4_io_end_t, list); | |
246 | BUG_ON(!(io->flag & EXT4_IO_END_UNWRITTEN)); | |
247 | list_del_init(&io->list); | |
248 | ||
249 | err = ext4_end_io(io); | |
250 | if (unlikely(!ret && err)) | |
251 | ret = err; | |
28a535f9 DM |
252 | } |
253 | return ret; | |
254 | } | |
255 | ||
256 | /* | |
2e8fa54e | 257 | * work on completed IO, to convert unwritten extents to extents |
28a535f9 | 258 | */ |
2e8fa54e JK |
259 | void ext4_end_io_rsv_work(struct work_struct *work) |
260 | { | |
261 | struct ext4_inode_info *ei = container_of(work, struct ext4_inode_info, | |
262 | i_rsv_conversion_work); | |
263 | ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_rsv_conversion_list); | |
264 | } | |
265 | ||
bd2d0210 TT |
266 | ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags) |
267 | { | |
b17b35ec | 268 | ext4_io_end_t *io = kmem_cache_zalloc(io_end_cachep, flags); |
bd2d0210 | 269 | if (io) { |
f7ad6d2e TT |
270 | atomic_inc(&EXT4_I(inode)->i_ioend_count); |
271 | io->inode = inode; | |
bd2d0210 | 272 | INIT_LIST_HEAD(&io->list); |
97a851ed | 273 | atomic_set(&io->count, 1); |
bd2d0210 TT |
274 | } |
275 | return io; | |
276 | } | |
277 | ||
97a851ed JK |
278 | void ext4_put_io_end_defer(ext4_io_end_t *io_end) |
279 | { | |
280 | if (atomic_dec_and_test(&io_end->count)) { | |
281 | if (!(io_end->flag & EXT4_IO_END_UNWRITTEN) || !io_end->size) { | |
282 | ext4_release_io_end(io_end); | |
283 | return; | |
284 | } | |
285 | ext4_add_complete_io(io_end); | |
286 | } | |
287 | } | |
288 | ||
289 | int ext4_put_io_end(ext4_io_end_t *io_end) | |
290 | { | |
291 | int err = 0; | |
292 | ||
293 | if (atomic_dec_and_test(&io_end->count)) { | |
294 | if (io_end->flag & EXT4_IO_END_UNWRITTEN) { | |
6b523df4 JK |
295 | err = ext4_convert_unwritten_extents(io_end->handle, |
296 | io_end->inode, io_end->offset, | |
297 | io_end->size); | |
298 | io_end->handle = NULL; | |
97a851ed JK |
299 | ext4_clear_io_unwritten_flag(io_end); |
300 | } | |
301 | ext4_release_io_end(io_end); | |
302 | } | |
303 | return err; | |
304 | } | |
305 | ||
306 | ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end) | |
307 | { | |
308 | atomic_inc(&io_end->count); | |
309 | return io_end; | |
310 | } | |
311 | ||
822dbba3 | 312 | /* BIO completion function for page writeback */ |
bd2d0210 TT |
313 | static void ext4_end_bio(struct bio *bio, int error) |
314 | { | |
315 | ext4_io_end_t *io_end = bio->bi_private; | |
4f024f37 | 316 | sector_t bi_sector = bio->bi_iter.bi_sector; |
bd2d0210 TT |
317 | |
318 | BUG_ON(!io_end); | |
bd2d0210 TT |
319 | bio->bi_end_io = NULL; |
320 | if (test_bit(BIO_UPTODATE, &bio->bi_flags)) | |
321 | error = 0; | |
0058f965 | 322 | |
f7ad6d2e | 323 | if (error) { |
b0857d30 JK |
324 | struct inode *inode = io_end->inode; |
325 | ||
9503c67c | 326 | ext4_warning(inode->i_sb, "I/O error %d writing to inode %lu " |
f7ad6d2e | 327 | "(offset %llu size %ld starting block %llu)", |
9503c67c | 328 | error, inode->i_ino, |
f7ad6d2e TT |
329 | (unsigned long long) io_end->offset, |
330 | (long) io_end->size, | |
331 | (unsigned long long) | |
d50bdd5a | 332 | bi_sector >> (inode->i_blkbits - 9)); |
9503c67c | 333 | mapping_set_error(inode->i_mapping, error); |
f7ad6d2e | 334 | } |
822dbba3 JK |
335 | |
336 | if (io_end->flag & EXT4_IO_END_UNWRITTEN) { | |
337 | /* | |
338 | * Link bio into list hanging from io_end. We have to do it | |
339 | * atomically as bio completions can be racing against each | |
340 | * other. | |
341 | */ | |
342 | bio->bi_private = xchg(&io_end->bio, bio); | |
343 | ext4_put_io_end_defer(io_end); | |
344 | } else { | |
345 | /* | |
346 | * Drop io_end reference early. Inode can get freed once | |
347 | * we finish the bio. | |
348 | */ | |
349 | ext4_put_io_end_defer(io_end); | |
350 | ext4_finish_bio(bio); | |
351 | bio_put(bio); | |
352 | } | |
bd2d0210 TT |
353 | } |
354 | ||
355 | void ext4_io_submit(struct ext4_io_submit *io) | |
356 | { | |
357 | struct bio *bio = io->io_bio; | |
358 | ||
359 | if (bio) { | |
360 | bio_get(io->io_bio); | |
361 | submit_bio(io->io_op, io->io_bio); | |
bd2d0210 TT |
362 | bio_put(io->io_bio); |
363 | } | |
7dc57615 | 364 | io->io_bio = NULL; |
97a851ed JK |
365 | } |
366 | ||
367 | void ext4_io_submit_init(struct ext4_io_submit *io, | |
368 | struct writeback_control *wbc) | |
369 | { | |
370 | io->io_op = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE); | |
371 | io->io_bio = NULL; | |
7dc57615 | 372 | io->io_end = NULL; |
bd2d0210 TT |
373 | } |
374 | ||
97a851ed JK |
375 | static int io_submit_init_bio(struct ext4_io_submit *io, |
376 | struct buffer_head *bh) | |
bd2d0210 | 377 | { |
bd2d0210 TT |
378 | int nvecs = bio_get_nr_vecs(bh->b_bdev); |
379 | struct bio *bio; | |
380 | ||
275d3ba6 | 381 | bio = bio_alloc(GFP_NOIO, min(nvecs, BIO_MAX_PAGES)); |
a1d8d9a7 TT |
382 | if (!bio) |
383 | return -ENOMEM; | |
4f024f37 | 384 | bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9); |
bd2d0210 | 385 | bio->bi_bdev = bh->b_bdev; |
bd2d0210 | 386 | bio->bi_end_io = ext4_end_bio; |
97a851ed | 387 | bio->bi_private = ext4_get_io_end(io->io_end); |
bd2d0210 | 388 | io->io_bio = bio; |
bd2d0210 TT |
389 | io->io_next_block = bh->b_blocknr; |
390 | return 0; | |
391 | } | |
392 | ||
393 | static int io_submit_add_bh(struct ext4_io_submit *io, | |
bd2d0210 | 394 | struct inode *inode, |
2058f83a | 395 | struct page *page, |
bd2d0210 TT |
396 | struct buffer_head *bh) |
397 | { | |
bd2d0210 TT |
398 | int ret; |
399 | ||
bd2d0210 TT |
400 | if (io->io_bio && bh->b_blocknr != io->io_next_block) { |
401 | submit_and_retry: | |
402 | ext4_io_submit(io); | |
403 | } | |
404 | if (io->io_bio == NULL) { | |
97a851ed | 405 | ret = io_submit_init_bio(io, bh); |
bd2d0210 TT |
406 | if (ret) |
407 | return ret; | |
408 | } | |
2058f83a | 409 | ret = bio_add_page(io->io_bio, page, bh->b_size, bh_offset(bh)); |
97a851ed JK |
410 | if (ret != bh->b_size) |
411 | goto submit_and_retry; | |
bd2d0210 | 412 | io->io_next_block++; |
bd2d0210 TT |
413 | return 0; |
414 | } | |
415 | ||
416 | int ext4_bio_write_page(struct ext4_io_submit *io, | |
417 | struct page *page, | |
418 | int len, | |
1c8349a1 NJ |
419 | struct writeback_control *wbc, |
420 | bool keep_towrite) | |
bd2d0210 | 421 | { |
2058f83a | 422 | struct page *data_page = NULL; |
bd2d0210 | 423 | struct inode *inode = page->mapping->host; |
0058f965 | 424 | unsigned block_start, blocksize; |
bd2d0210 TT |
425 | struct buffer_head *bh, *head; |
426 | int ret = 0; | |
0058f965 | 427 | int nr_submitted = 0; |
bd2d0210 TT |
428 | |
429 | blocksize = 1 << inode->i_blkbits; | |
430 | ||
d50bdd5a | 431 | BUG_ON(!PageLocked(page)); |
bd2d0210 | 432 | BUG_ON(PageWriteback(page)); |
bd2d0210 | 433 | |
1c8349a1 NJ |
434 | if (keep_towrite) |
435 | set_page_writeback_keepwrite(page); | |
436 | else | |
437 | set_page_writeback(page); | |
a54aa761 | 438 | ClearPageError(page); |
bd2d0210 | 439 | |
eeece469 | 440 | /* |
f8409abd | 441 | * Comments copied from block_write_full_page: |
eeece469 JK |
442 | * |
443 | * The page straddles i_size. It must be zeroed out on each and every | |
444 | * writepage invocation because it may be mmapped. "A file is mapped | |
445 | * in multiples of the page size. For a file that is not a multiple of | |
446 | * the page size, the remaining memory is zeroed when mapped, and | |
447 | * writes to that region are not written out to the file." | |
448 | */ | |
449 | if (len < PAGE_CACHE_SIZE) | |
450 | zero_user_segment(page, len, PAGE_CACHE_SIZE); | |
0058f965 JK |
451 | /* |
452 | * In the first loop we prepare and mark buffers to submit. We have to | |
453 | * mark all buffers in the page before submitting so that | |
454 | * end_page_writeback() cannot be called from ext4_bio_end_io() when IO | |
455 | * on the first buffer finishes and we are still working on submitting | |
456 | * the second buffer. | |
457 | */ | |
458 | bh = head = page_buffers(page); | |
459 | do { | |
460 | block_start = bh_offset(bh); | |
bd2d0210 TT |
461 | if (block_start >= len) { |
462 | clear_buffer_dirty(bh); | |
463 | set_buffer_uptodate(bh); | |
464 | continue; | |
465 | } | |
8a850c3f JK |
466 | if (!buffer_dirty(bh) || buffer_delay(bh) || |
467 | !buffer_mapped(bh) || buffer_unwritten(bh)) { | |
468 | /* A hole? We can safely clear the dirty bit */ | |
469 | if (!buffer_mapped(bh)) | |
470 | clear_buffer_dirty(bh); | |
471 | if (io->io_bio) | |
472 | ext4_io_submit(io); | |
473 | continue; | |
474 | } | |
0058f965 JK |
475 | if (buffer_new(bh)) { |
476 | clear_buffer_new(bh); | |
477 | unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr); | |
478 | } | |
479 | set_buffer_async_write(bh); | |
480 | } while ((bh = bh->b_this_page) != head); | |
481 | ||
0058f965 | 482 | bh = head = page_buffers(page); |
2058f83a MH |
483 | |
484 | if (ext4_encrypted_inode(inode) && S_ISREG(inode->i_mode)) { | |
485 | data_page = ext4_encrypt(inode, page); | |
486 | if (IS_ERR(data_page)) { | |
487 | ret = PTR_ERR(data_page); | |
488 | data_page = NULL; | |
489 | goto out; | |
490 | } | |
491 | } | |
492 | ||
493 | /* Now submit buffers to write */ | |
0058f965 JK |
494 | do { |
495 | if (!buffer_async_write(bh)) | |
496 | continue; | |
2058f83a MH |
497 | ret = io_submit_add_bh(io, inode, |
498 | data_page ? data_page : page, bh); | |
bd2d0210 TT |
499 | if (ret) { |
500 | /* | |
501 | * We only get here on ENOMEM. Not much else | |
502 | * we can do but mark the page as dirty, and | |
503 | * better luck next time. | |
504 | */ | |
bd2d0210 TT |
505 | break; |
506 | } | |
0058f965 | 507 | nr_submitted++; |
1ae48a63 | 508 | clear_buffer_dirty(bh); |
0058f965 JK |
509 | } while ((bh = bh->b_this_page) != head); |
510 | ||
511 | /* Error stopped previous loop? Clean up buffers... */ | |
512 | if (ret) { | |
2058f83a MH |
513 | out: |
514 | if (data_page) | |
515 | ext4_restore_control_page(data_page); | |
516 | printk_ratelimited(KERN_ERR "%s: ret = %d\n", __func__, ret); | |
517 | redirty_page_for_writepage(wbc, page); | |
0058f965 JK |
518 | do { |
519 | clear_buffer_async_write(bh); | |
520 | bh = bh->b_this_page; | |
521 | } while (bh != head); | |
bd2d0210 TT |
522 | } |
523 | unlock_page(page); | |
0058f965 JK |
524 | /* Nothing submitted - we have to end page writeback */ |
525 | if (!nr_submitted) | |
526 | end_page_writeback(page); | |
bd2d0210 TT |
527 | return ret; |
528 | } |