Commit | Line | Data |
---|---|---|
b3b94faa DT |
1 | /* |
2 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
3 | * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. | |
4 | * | |
5 | * This copyrighted material is made available to anyone wishing to use, | |
6 | * modify, copy, or redistribute it subject to the terms and conditions | |
7 | * of the GNU General Public License v.2. | |
8 | */ | |
9 | ||
10 | #include <linux/sched.h> | |
11 | #include <linux/slab.h> | |
12 | #include <linux/spinlock.h> | |
13 | #include <linux/completion.h> | |
14 | #include <linux/buffer_head.h> | |
15 | #include <linux/pagemap.h> | |
9b124fbb | 16 | #include <linux/mpage.h> |
d1665e41 | 17 | #include <linux/fs.h> |
5c676f6d | 18 | #include <linux/gfs2_ondisk.h> |
b3b94faa DT |
19 | #include <asm/semaphore.h> |
20 | ||
21 | #include "gfs2.h" | |
5c676f6d SW |
22 | #include "lm_interface.h" |
23 | #include "incore.h" | |
b3b94faa DT |
24 | #include "bmap.h" |
25 | #include "glock.h" | |
26 | #include "inode.h" | |
b3b94faa DT |
27 | #include "log.h" |
28 | #include "meta_io.h" | |
29 | #include "ops_address.h" | |
30 | #include "page.h" | |
31 | #include "quota.h" | |
32 | #include "trans.h" | |
18ec7d5c | 33 | #include "rgrp.h" |
61a30dcb | 34 | #include "ops_file.h" |
5c676f6d | 35 | #include "util.h" |
b3b94faa DT |
36 | |
37 | /** | |
4ff14670 | 38 | * gfs2_get_block - Fills in a buffer head with details about a block |
b3b94faa DT |
39 | * @inode: The inode |
40 | * @lblock: The block number to look up | |
41 | * @bh_result: The buffer head to return the result in | |
42 | * @create: Non-zero if we may add block to the file | |
43 | * | |
44 | * Returns: errno | |
45 | */ | |
46 | ||
4ff14670 SW |
47 | int gfs2_get_block(struct inode *inode, sector_t lblock, |
48 | struct buffer_head *bh_result, int create) | |
b3b94faa | 49 | { |
5c676f6d | 50 | struct gfs2_inode *ip = inode->u.generic_ip; |
b3b94faa DT |
51 | int new = create; |
52 | uint64_t dblock; | |
53 | int error; | |
54 | ||
55 | error = gfs2_block_map(ip, lblock, &new, &dblock, NULL); | |
56 | if (error) | |
57 | return error; | |
58 | ||
59 | if (!dblock) | |
60 | return 0; | |
61 | ||
62 | map_bh(bh_result, inode->i_sb, dblock); | |
63 | if (new) | |
64 | set_buffer_new(bh_result); | |
65 | ||
66 | return 0; | |
67 | } | |
68 | ||
69 | /** | |
70 | * get_block_noalloc - Fills in a buffer head with details about a block | |
71 | * @inode: The inode | |
72 | * @lblock: The block number to look up | |
73 | * @bh_result: The buffer head to return the result in | |
74 | * @create: Non-zero if we may add block to the file | |
75 | * | |
76 | * Returns: errno | |
77 | */ | |
78 | ||
79 | static int get_block_noalloc(struct inode *inode, sector_t lblock, | |
80 | struct buffer_head *bh_result, int create) | |
81 | { | |
5c676f6d | 82 | struct gfs2_inode *ip = inode->u.generic_ip; |
b3b94faa DT |
83 | int new = 0; |
84 | uint64_t dblock; | |
85 | int error; | |
86 | ||
87 | error = gfs2_block_map(ip, lblock, &new, &dblock, NULL); | |
88 | if (error) | |
89 | return error; | |
90 | ||
91 | if (dblock) | |
92 | map_bh(bh_result, inode->i_sb, dblock); | |
93 | else if (gfs2_assert_withdraw(ip->i_sbd, !create)) | |
94 | error = -EIO; | |
95 | ||
96 | return error; | |
97 | } | |
98 | ||
99 | static int get_blocks(struct inode *inode, sector_t lblock, | |
100 | unsigned long max_blocks, struct buffer_head *bh_result, | |
101 | int create) | |
102 | { | |
5c676f6d | 103 | struct gfs2_inode *ip = inode->u.generic_ip; |
b3b94faa DT |
104 | int new = create; |
105 | uint64_t dblock; | |
106 | uint32_t extlen; | |
107 | int error; | |
108 | ||
109 | error = gfs2_block_map(ip, lblock, &new, &dblock, &extlen); | |
110 | if (error) | |
111 | return error; | |
112 | ||
113 | if (!dblock) | |
114 | return 0; | |
115 | ||
116 | map_bh(bh_result, inode->i_sb, dblock); | |
117 | if (new) | |
118 | set_buffer_new(bh_result); | |
119 | ||
120 | if (extlen > max_blocks) | |
121 | extlen = max_blocks; | |
122 | bh_result->b_size = extlen << inode->i_blkbits; | |
123 | ||
124 | return 0; | |
125 | } | |
126 | ||
127 | static int get_blocks_noalloc(struct inode *inode, sector_t lblock, | |
128 | unsigned long max_blocks, | |
129 | struct buffer_head *bh_result, int create) | |
130 | { | |
5c676f6d | 131 | struct gfs2_inode *ip = inode->u.generic_ip; |
b3b94faa DT |
132 | int new = 0; |
133 | uint64_t dblock; | |
134 | uint32_t extlen; | |
135 | int error; | |
136 | ||
137 | error = gfs2_block_map(ip, lblock, &new, &dblock, &extlen); | |
138 | if (error) | |
139 | return error; | |
140 | ||
141 | if (dblock) { | |
142 | map_bh(bh_result, inode->i_sb, dblock); | |
143 | if (extlen > max_blocks) | |
144 | extlen = max_blocks; | |
145 | bh_result->b_size = extlen << inode->i_blkbits; | |
146 | } else if (gfs2_assert_withdraw(ip->i_sbd, !create)) | |
147 | error = -EIO; | |
148 | ||
149 | return error; | |
150 | } | |
151 | ||
152 | /** | |
153 | * gfs2_writepage - Write complete page | |
154 | * @page: Page to write | |
155 | * | |
156 | * Returns: errno | |
157 | * | |
18ec7d5c SW |
158 | * Some of this is copied from block_write_full_page() although we still |
159 | * call it to do most of the work. | |
b3b94faa DT |
160 | */ |
161 | ||
162 | static int gfs2_writepage(struct page *page, struct writeback_control *wbc) | |
163 | { | |
18ec7d5c | 164 | struct inode *inode = page->mapping->host; |
5c676f6d | 165 | struct gfs2_inode *ip = page->mapping->host->u.generic_ip; |
b3b94faa | 166 | struct gfs2_sbd *sdp = ip->i_sbd; |
18ec7d5c SW |
167 | loff_t i_size = i_size_read(inode); |
168 | pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT; | |
169 | unsigned offset; | |
b3b94faa | 170 | int error; |
18ec7d5c | 171 | int done_trans = 0; |
b3b94faa | 172 | |
b3b94faa DT |
173 | if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl))) { |
174 | unlock_page(page); | |
175 | return -EIO; | |
176 | } | |
5c676f6d | 177 | if (current->journal_info) |
18ec7d5c SW |
178 | goto out_ignore; |
179 | ||
180 | /* Is the page fully outside i_size? (truncate in progress) */ | |
181 | offset = i_size & (PAGE_CACHE_SIZE-1); | |
182 | if (page->index >= end_index+1 || !offset) { | |
183 | page->mapping->a_ops->invalidatepage(page, 0); | |
b3b94faa | 184 | unlock_page(page); |
18ec7d5c | 185 | return 0; /* don't care */ |
b3b94faa DT |
186 | } |
187 | ||
18ec7d5c SW |
188 | if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip)) { |
189 | error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0); | |
190 | if (error) | |
191 | goto out_ignore; | |
192 | gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize-1); | |
193 | done_trans = 1; | |
194 | } | |
18ec7d5c SW |
195 | error = block_write_full_page(page, get_block_noalloc, wbc); |
196 | if (done_trans) | |
197 | gfs2_trans_end(sdp); | |
b3b94faa | 198 | gfs2_meta_cache_flush(ip); |
b3b94faa | 199 | return error; |
18ec7d5c SW |
200 | |
201 | out_ignore: | |
202 | redirty_page_for_writepage(wbc, page); | |
203 | unlock_page(page); | |
204 | return 0; | |
b3b94faa DT |
205 | } |
206 | ||
207 | /** | |
208 | * stuffed_readpage - Fill in a Linux page with stuffed file data | |
209 | * @ip: the inode | |
210 | * @page: the page | |
211 | * | |
212 | * Returns: errno | |
213 | */ | |
214 | ||
215 | static int stuffed_readpage(struct gfs2_inode *ip, struct page *page) | |
216 | { | |
217 | struct buffer_head *dibh; | |
218 | void *kaddr; | |
219 | int error; | |
220 | ||
221 | error = gfs2_meta_inode_buffer(ip, &dibh); | |
222 | if (error) | |
223 | return error; | |
224 | ||
5c4e9e03 | 225 | kaddr = kmap_atomic(page, KM_USER0); |
b3b94faa DT |
226 | memcpy((char *)kaddr, |
227 | dibh->b_data + sizeof(struct gfs2_dinode), | |
228 | ip->i_di.di_size); | |
229 | memset((char *)kaddr + ip->i_di.di_size, | |
230 | 0, | |
231 | PAGE_CACHE_SIZE - ip->i_di.di_size); | |
5c4e9e03 | 232 | kunmap_atomic(page, KM_USER0); |
b3b94faa DT |
233 | |
234 | brelse(dibh); | |
235 | ||
236 | SetPageUptodate(page); | |
237 | ||
238 | return 0; | |
239 | } | |
240 | ||
241 | static int zero_readpage(struct page *page) | |
242 | { | |
243 | void *kaddr; | |
244 | ||
5c4e9e03 | 245 | kaddr = kmap_atomic(page, KM_USER0); |
b3b94faa | 246 | memset(kaddr, 0, PAGE_CACHE_SIZE); |
5c4e9e03 | 247 | kunmap_atomic(page, KM_USER0); |
b3b94faa DT |
248 | |
249 | SetPageUptodate(page); | |
250 | unlock_page(page); | |
251 | ||
252 | return 0; | |
253 | } | |
254 | ||
b3b94faa DT |
255 | /** |
256 | * gfs2_readpage - readpage with locking | |
18ec7d5c SW |
257 | * @file: The file to read a page for. N.B. This may be NULL if we are |
258 | * reading an internal file. | |
b3b94faa DT |
259 | * @page: The page to read |
260 | * | |
261 | * Returns: errno | |
262 | */ | |
263 | ||
264 | static int gfs2_readpage(struct file *file, struct page *page) | |
265 | { | |
5c676f6d | 266 | struct gfs2_inode *ip = page->mapping->host->u.generic_ip; |
b3b94faa | 267 | struct gfs2_sbd *sdp = ip->i_sbd; |
18ec7d5c | 268 | struct gfs2_holder gh; |
b3b94faa DT |
269 | int error; |
270 | ||
61a30dcb SW |
271 | if (file != &gfs2_internal_file_sentinal) { |
272 | gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh); | |
273 | error = gfs2_glock_nq_m_atime(1, &gh); | |
274 | if (error) | |
275 | goto out_unlock; | |
276 | } | |
b3b94faa | 277 | |
18ec7d5c SW |
278 | if (gfs2_is_stuffed(ip)) { |
279 | if (!page->index) { | |
280 | error = stuffed_readpage(ip, page); | |
281 | unlock_page(page); | |
b3b94faa | 282 | } else |
18ec7d5c | 283 | error = zero_readpage(page); |
b3b94faa | 284 | } else |
18ec7d5c | 285 | error = mpage_readpage(page, gfs2_get_block); |
b3b94faa DT |
286 | |
287 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) | |
288 | error = -EIO; | |
289 | ||
61a30dcb SW |
290 | if (file != &gfs2_internal_file_sentinal) { |
291 | gfs2_glock_dq_m(1, &gh); | |
292 | gfs2_holder_uninit(&gh); | |
293 | } | |
18ec7d5c | 294 | out: |
b3b94faa | 295 | return error; |
18ec7d5c SW |
296 | out_unlock: |
297 | unlock_page(page); | |
298 | goto out; | |
b3b94faa DT |
299 | } |
300 | ||
301 | /** | |
302 | * gfs2_prepare_write - Prepare to write a page to a file | |
303 | * @file: The file to write to | |
304 | * @page: The page which is to be prepared for writing | |
305 | * @from: From (byte range within page) | |
306 | * @to: To (byte range within page) | |
307 | * | |
308 | * Returns: errno | |
309 | */ | |
310 | ||
311 | static int gfs2_prepare_write(struct file *file, struct page *page, | |
312 | unsigned from, unsigned to) | |
313 | { | |
5c676f6d | 314 | struct gfs2_inode *ip = page->mapping->host->u.generic_ip; |
b3b94faa | 315 | struct gfs2_sbd *sdp = ip->i_sbd; |
18ec7d5c SW |
316 | unsigned int data_blocks, ind_blocks, rblocks; |
317 | int alloc_required; | |
b3b94faa | 318 | int error = 0; |
18ec7d5c SW |
319 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + from; |
320 | loff_t end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
321 | struct gfs2_alloc *al; | |
b3b94faa | 322 | |
18ec7d5c SW |
323 | gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME, &ip->i_gh); |
324 | error = gfs2_glock_nq_m_atime(1, &ip->i_gh); | |
325 | if (error) | |
326 | goto out_uninit; | |
b3b94faa | 327 | |
18ec7d5c SW |
328 | gfs2_write_calc_reserv(ip, to - from, &data_blocks, &ind_blocks); |
329 | ||
330 | error = gfs2_write_alloc_required(ip, pos, from - to, &alloc_required); | |
331 | if (error) | |
332 | goto out_unlock; | |
b3b94faa | 333 | |
18ec7d5c SW |
334 | |
335 | if (alloc_required) { | |
336 | al = gfs2_alloc_get(ip); | |
337 | ||
338 | error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE); | |
339 | if (error) | |
340 | goto out_alloc_put; | |
341 | ||
342 | error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid); | |
343 | if (error) | |
344 | goto out_qunlock; | |
345 | ||
346 | al->al_requested = data_blocks + ind_blocks; | |
347 | error = gfs2_inplace_reserve(ip); | |
348 | if (error) | |
349 | goto out_qunlock; | |
350 | } | |
351 | ||
352 | rblocks = RES_DINODE + ind_blocks; | |
353 | if (gfs2_is_jdata(ip)) | |
354 | rblocks += data_blocks ? data_blocks : 1; | |
355 | if (ind_blocks || data_blocks) | |
356 | rblocks += RES_STATFS + RES_QUOTA; | |
357 | ||
358 | error = gfs2_trans_begin(sdp, rblocks, 0); | |
359 | if (error) | |
360 | goto out; | |
361 | ||
362 | if (gfs2_is_stuffed(ip)) { | |
363 | if (end > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) { | |
568f4c96 SW |
364 | error = gfs2_unstuff_dinode(ip, gfs2_unstuffer_page, |
365 | page); | |
5c4e9e03 SW |
366 | if (error == 0) |
367 | goto prepare_write; | |
368 | } else if (!PageUptodate(page)) | |
b3b94faa | 369 | error = stuffed_readpage(ip, page); |
5c4e9e03 | 370 | goto out; |
18ec7d5c SW |
371 | } |
372 | ||
5c4e9e03 | 373 | prepare_write: |
18ec7d5c SW |
374 | error = block_prepare_write(page, from, to, gfs2_get_block); |
375 | ||
376 | out: | |
377 | if (error) { | |
378 | gfs2_trans_end(sdp); | |
379 | if (alloc_required) { | |
380 | gfs2_inplace_release(ip); | |
381 | out_qunlock: | |
382 | gfs2_quota_unlock(ip); | |
383 | out_alloc_put: | |
384 | gfs2_alloc_put(ip); | |
385 | } | |
386 | out_unlock: | |
387 | gfs2_glock_dq_m(1, &ip->i_gh); | |
388 | out_uninit: | |
389 | gfs2_holder_uninit(&ip->i_gh); | |
390 | } | |
b3b94faa DT |
391 | |
392 | return error; | |
393 | } | |
394 | ||
395 | /** | |
396 | * gfs2_commit_write - Commit write to a file | |
397 | * @file: The file to write to | |
398 | * @page: The page containing the data | |
399 | * @from: From (byte range within page) | |
400 | * @to: To (byte range within page) | |
401 | * | |
402 | * Returns: errno | |
403 | */ | |
404 | ||
405 | static int gfs2_commit_write(struct file *file, struct page *page, | |
406 | unsigned from, unsigned to) | |
407 | { | |
408 | struct inode *inode = page->mapping->host; | |
5c676f6d | 409 | struct gfs2_inode *ip = inode->u.generic_ip; |
b3b94faa | 410 | struct gfs2_sbd *sdp = ip->i_sbd; |
18ec7d5c SW |
411 | int error = -EOPNOTSUPP; |
412 | struct buffer_head *dibh; | |
413 | struct gfs2_alloc *al = &ip->i_alloc;; | |
b3b94faa | 414 | |
18ec7d5c SW |
415 | if (gfs2_assert_withdraw(sdp, gfs2_glock_is_locked_by_me(ip->i_gl))) |
416 | goto fail_nounlock; | |
417 | ||
418 | error = gfs2_meta_inode_buffer(ip, &dibh); | |
419 | if (error) | |
420 | goto fail_endtrans; | |
421 | ||
422 | gfs2_trans_add_bh(ip->i_gl, dibh, 1); | |
423 | ||
b3b94faa | 424 | if (gfs2_is_stuffed(ip)) { |
b3b94faa DT |
425 | uint64_t file_size; |
426 | void *kaddr; | |
427 | ||
428 | file_size = ((uint64_t)page->index << PAGE_CACHE_SHIFT) + to; | |
429 | ||
18ec7d5c | 430 | kaddr = kmap_atomic(page, KM_USER0); |
b3b94faa | 431 | memcpy(dibh->b_data + sizeof(struct gfs2_dinode) + from, |
18ec7d5c SW |
432 | (char *)kaddr + from, to - from); |
433 | kunmap_atomic(page, KM_USER0); | |
b3b94faa DT |
434 | |
435 | SetPageUptodate(page); | |
436 | ||
437 | if (inode->i_size < file_size) | |
438 | i_size_write(inode, file_size); | |
439 | } else { | |
568f4c96 SW |
440 | if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || |
441 | gfs2_is_jdata(ip)) | |
257f9b4e | 442 | gfs2_page_add_databufs(ip, page, from, to); |
b3b94faa DT |
443 | error = generic_commit_write(file, page, from, to); |
444 | if (error) | |
445 | goto fail; | |
446 | } | |
447 | ||
18ec7d5c SW |
448 | if (ip->i_di.di_size < inode->i_size) |
449 | ip->i_di.di_size = inode->i_size; | |
450 | ||
451 | gfs2_dinode_out(&ip->i_di, dibh->b_data); | |
452 | brelse(dibh); | |
453 | gfs2_trans_end(sdp); | |
454 | if (al->al_requested) { | |
455 | gfs2_inplace_release(ip); | |
456 | gfs2_quota_unlock(ip); | |
457 | gfs2_alloc_put(ip); | |
458 | } | |
459 | gfs2_glock_dq_m(1, &ip->i_gh); | |
460 | gfs2_holder_uninit(&ip->i_gh); | |
b3b94faa DT |
461 | return 0; |
462 | ||
18ec7d5c SW |
463 | fail: |
464 | brelse(dibh); | |
465 | fail_endtrans: | |
466 | gfs2_trans_end(sdp); | |
467 | if (al->al_requested) { | |
468 | gfs2_inplace_release(ip); | |
469 | gfs2_quota_unlock(ip); | |
470 | gfs2_alloc_put(ip); | |
471 | } | |
472 | gfs2_glock_dq_m(1, &ip->i_gh); | |
473 | gfs2_holder_uninit(&ip->i_gh); | |
474 | fail_nounlock: | |
b3b94faa | 475 | ClearPageUptodate(page); |
b3b94faa DT |
476 | return error; |
477 | } | |
478 | ||
479 | /** | |
480 | * gfs2_bmap - Block map function | |
481 | * @mapping: Address space info | |
482 | * @lblock: The block to map | |
483 | * | |
484 | * Returns: The disk address for the block or 0 on hole or error | |
485 | */ | |
486 | ||
487 | static sector_t gfs2_bmap(struct address_space *mapping, sector_t lblock) | |
488 | { | |
5c676f6d | 489 | struct gfs2_inode *ip = mapping->host->u.generic_ip; |
b3b94faa DT |
490 | struct gfs2_holder i_gh; |
491 | sector_t dblock = 0; | |
492 | int error; | |
493 | ||
b3b94faa DT |
494 | error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh); |
495 | if (error) | |
496 | return 0; | |
497 | ||
498 | if (!gfs2_is_stuffed(ip)) | |
4ff14670 | 499 | dblock = generic_block_bmap(mapping, lblock, gfs2_get_block); |
b3b94faa DT |
500 | |
501 | gfs2_glock_dq_uninit(&i_gh); | |
502 | ||
503 | return dblock; | |
504 | } | |
505 | ||
506 | static void discard_buffer(struct gfs2_sbd *sdp, struct buffer_head *bh) | |
507 | { | |
64fb4eb7 | 508 | struct gfs2_bufdata *bd; |
b3b94faa DT |
509 | |
510 | gfs2_log_lock(sdp); | |
5c676f6d | 511 | bd = bh->b_private; |
64fb4eb7 SW |
512 | if (bd) { |
513 | bd->bd_bh = NULL; | |
5c676f6d | 514 | bh->b_private = NULL; |
b3b94faa DT |
515 | gfs2_log_unlock(sdp); |
516 | brelse(bh); | |
517 | } else | |
518 | gfs2_log_unlock(sdp); | |
519 | ||
520 | lock_buffer(bh); | |
521 | clear_buffer_dirty(bh); | |
522 | bh->b_bdev = NULL; | |
523 | clear_buffer_mapped(bh); | |
524 | clear_buffer_req(bh); | |
525 | clear_buffer_new(bh); | |
526 | clear_buffer_delay(bh); | |
527 | unlock_buffer(bh); | |
528 | } | |
529 | ||
530 | static int gfs2_invalidatepage(struct page *page, unsigned long offset) | |
531 | { | |
5c676f6d | 532 | struct gfs2_sbd *sdp = page->mapping->host->i_sb->s_fs_info; |
b3b94faa DT |
533 | struct buffer_head *head, *bh, *next; |
534 | unsigned int curr_off = 0; | |
535 | int ret = 1; | |
536 | ||
537 | BUG_ON(!PageLocked(page)); | |
538 | if (!page_has_buffers(page)) | |
539 | return 1; | |
540 | ||
541 | bh = head = page_buffers(page); | |
542 | do { | |
543 | unsigned int next_off = curr_off + bh->b_size; | |
544 | next = bh->b_this_page; | |
545 | ||
546 | if (offset <= curr_off) | |
547 | discard_buffer(sdp, bh); | |
548 | ||
549 | curr_off = next_off; | |
550 | bh = next; | |
551 | } while (bh != head); | |
552 | ||
553 | if (!offset) | |
554 | ret = try_to_release_page(page, 0); | |
555 | ||
556 | return ret; | |
557 | } | |
558 | ||
d1665e41 SW |
559 | static ssize_t gfs2_direct_IO_write(struct kiocb *iocb, const struct iovec *iov, |
560 | loff_t offset, unsigned long nr_segs) | |
561 | { | |
562 | struct file *file = iocb->ki_filp; | |
563 | struct inode *inode = file->f_mapping->host; | |
5c676f6d | 564 | struct gfs2_inode *ip = inode->u.generic_ip; |
d1665e41 SW |
565 | struct gfs2_holder gh; |
566 | int rv; | |
567 | ||
568 | /* | |
569 | * Shared lock, even though its write, since we do no allocation | |
570 | * on this path. All we need change is atime. | |
571 | */ | |
572 | gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh); | |
573 | rv = gfs2_glock_nq_m_atime(1, &gh); | |
574 | if (rv) | |
575 | goto out; | |
576 | ||
577 | /* | |
578 | * Should we return an error here? I can't see that O_DIRECT for | |
579 | * a journaled file makes any sense. For now we'll silently fall | |
580 | * back to buffered I/O, likewise we do the same for stuffed | |
581 | * files since they are (a) small and (b) unaligned. | |
582 | */ | |
583 | if (gfs2_is_jdata(ip)) | |
584 | goto out; | |
585 | ||
586 | if (gfs2_is_stuffed(ip)) | |
587 | goto out; | |
588 | ||
589 | rv = __blockdev_direct_IO(WRITE, iocb, inode, inode->i_sb->s_bdev, | |
590 | iov, offset, nr_segs, get_blocks_noalloc, | |
591 | NULL, DIO_OWN_LOCKING); | |
592 | out: | |
593 | gfs2_glock_dq_m(1, &gh); | |
594 | gfs2_holder_uninit(&gh); | |
595 | ||
596 | return rv; | |
597 | } | |
598 | ||
599 | /** | |
600 | * gfs2_direct_IO | |
601 | * | |
602 | * This is called with a shared lock already held for the read path. | |
603 | * Currently, no locks are held when the write path is called. | |
604 | */ | |
605 | static ssize_t gfs2_direct_IO(int rw, struct kiocb *iocb, | |
606 | const struct iovec *iov, loff_t offset, | |
607 | unsigned long nr_segs) | |
b3b94faa DT |
608 | { |
609 | struct file *file = iocb->ki_filp; | |
610 | struct inode *inode = file->f_mapping->host; | |
5c676f6d | 611 | struct gfs2_inode *ip = inode->u.generic_ip; |
b3b94faa | 612 | struct gfs2_sbd *sdp = ip->i_sbd; |
b3b94faa | 613 | |
d1665e41 SW |
614 | if (rw == WRITE) |
615 | return gfs2_direct_IO_write(iocb, iov, offset, nr_segs); | |
b3b94faa | 616 | |
d1665e41 SW |
617 | if (gfs2_assert_warn(sdp, gfs2_glock_is_locked_by_me(ip->i_gl)) || |
618 | gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip))) | |
619 | return -EINVAL; | |
b3b94faa | 620 | |
d1665e41 SW |
621 | return __blockdev_direct_IO(READ, iocb, inode, inode->i_sb->s_bdev, iov, |
622 | offset, nr_segs, get_blocks, NULL, | |
623 | DIO_OWN_LOCKING); | |
b3b94faa DT |
624 | } |
625 | ||
626 | struct address_space_operations gfs2_file_aops = { | |
627 | .writepage = gfs2_writepage, | |
628 | .readpage = gfs2_readpage, | |
629 | .sync_page = block_sync_page, | |
630 | .prepare_write = gfs2_prepare_write, | |
631 | .commit_write = gfs2_commit_write, | |
632 | .bmap = gfs2_bmap, | |
633 | .invalidatepage = gfs2_invalidatepage, | |
634 | .direct_IO = gfs2_direct_IO, | |
635 | }; | |
636 |