Commit | Line | Data |
---|---|---|
b3b94faa DT |
1 | /* |
2 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
3a8a9a10 | 3 | * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. |
b3b94faa DT |
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> | |
fd88de56 | 16 | #include <linux/pagevec.h> |
9b124fbb | 17 | #include <linux/mpage.h> |
d1665e41 | 18 | #include <linux/fs.h> |
5c676f6d | 19 | #include <linux/gfs2_ondisk.h> |
b3b94faa DT |
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 | { |
b3b94faa DT |
50 | int new = create; |
51 | uint64_t dblock; | |
52 | int error; | |
fd88de56 | 53 | int boundary; |
b3b94faa | 54 | |
fd88de56 | 55 | error = gfs2_block_map(inode, lblock, &new, &dblock, &boundary); |
b3b94faa DT |
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); | |
fd88de56 SW |
65 | if (boundary) |
66 | set_buffer_boundary(bh_result); | |
b3b94faa DT |
67 | |
68 | return 0; | |
69 | } | |
70 | ||
71 | /** | |
72 | * get_block_noalloc - Fills in a buffer head with details about a block | |
73 | * @inode: The inode | |
74 | * @lblock: The block number to look up | |
75 | * @bh_result: The buffer head to return the result in | |
76 | * @create: Non-zero if we may add block to the file | |
77 | * | |
78 | * Returns: errno | |
79 | */ | |
80 | ||
81 | static int get_block_noalloc(struct inode *inode, sector_t lblock, | |
82 | struct buffer_head *bh_result, int create) | |
83 | { | |
b3b94faa DT |
84 | int new = 0; |
85 | uint64_t dblock; | |
86 | int error; | |
fd88de56 | 87 | int boundary; |
b3b94faa | 88 | |
fd88de56 | 89 | error = gfs2_block_map(inode, lblock, &new, &dblock, &boundary); |
b3b94faa DT |
90 | if (error) |
91 | return error; | |
92 | ||
93 | if (dblock) | |
94 | map_bh(bh_result, inode->i_sb, dblock); | |
feaa7bba | 95 | else if (gfs2_assert_withdraw(GFS2_SB(inode), !create)) |
b3b94faa | 96 | error = -EIO; |
fd88de56 SW |
97 | if (boundary) |
98 | set_buffer_boundary(bh_result); | |
b3b94faa DT |
99 | |
100 | return error; | |
101 | } | |
102 | ||
b3b94faa DT |
103 | /** |
104 | * gfs2_writepage - Write complete page | |
105 | * @page: Page to write | |
106 | * | |
107 | * Returns: errno | |
108 | * | |
18ec7d5c SW |
109 | * Some of this is copied from block_write_full_page() although we still |
110 | * call it to do most of the work. | |
b3b94faa DT |
111 | */ |
112 | ||
113 | static int gfs2_writepage(struct page *page, struct writeback_control *wbc) | |
114 | { | |
18ec7d5c | 115 | struct inode *inode = page->mapping->host; |
feaa7bba SW |
116 | struct gfs2_inode *ip = GFS2_I(page->mapping->host); |
117 | struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host); | |
18ec7d5c SW |
118 | loff_t i_size = i_size_read(inode); |
119 | pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT; | |
120 | unsigned offset; | |
b3b94faa | 121 | int error; |
18ec7d5c | 122 | int done_trans = 0; |
b3b94faa | 123 | |
b3b94faa DT |
124 | if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl))) { |
125 | unlock_page(page); | |
126 | return -EIO; | |
127 | } | |
5c676f6d | 128 | if (current->journal_info) |
18ec7d5c SW |
129 | goto out_ignore; |
130 | ||
131 | /* Is the page fully outside i_size? (truncate in progress) */ | |
132 | offset = i_size & (PAGE_CACHE_SIZE-1); | |
d2d7b8a2 | 133 | if (page->index > end_index || (page->index == end_index && !offset)) { |
18ec7d5c | 134 | page->mapping->a_ops->invalidatepage(page, 0); |
b3b94faa | 135 | unlock_page(page); |
18ec7d5c | 136 | return 0; /* don't care */ |
b3b94faa DT |
137 | } |
138 | ||
18ec7d5c SW |
139 | if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip)) { |
140 | error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0); | |
141 | if (error) | |
142 | goto out_ignore; | |
143 | gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize-1); | |
144 | done_trans = 1; | |
145 | } | |
18ec7d5c SW |
146 | error = block_write_full_page(page, get_block_noalloc, wbc); |
147 | if (done_trans) | |
148 | gfs2_trans_end(sdp); | |
b3b94faa | 149 | gfs2_meta_cache_flush(ip); |
b3b94faa | 150 | return error; |
18ec7d5c SW |
151 | |
152 | out_ignore: | |
153 | redirty_page_for_writepage(wbc, page); | |
154 | unlock_page(page); | |
155 | return 0; | |
b3b94faa DT |
156 | } |
157 | ||
fd88de56 SW |
158 | static int zero_readpage(struct page *page) |
159 | { | |
160 | void *kaddr; | |
161 | ||
162 | kaddr = kmap_atomic(page, KM_USER0); | |
163 | memset(kaddr, 0, PAGE_CACHE_SIZE); | |
164 | kunmap_atomic(page, KM_USER0); | |
165 | ||
166 | SetPageUptodate(page); | |
167 | ||
168 | return 0; | |
169 | } | |
170 | ||
b3b94faa DT |
171 | /** |
172 | * stuffed_readpage - Fill in a Linux page with stuffed file data | |
173 | * @ip: the inode | |
174 | * @page: the page | |
175 | * | |
176 | * Returns: errno | |
177 | */ | |
178 | ||
179 | static int stuffed_readpage(struct gfs2_inode *ip, struct page *page) | |
180 | { | |
181 | struct buffer_head *dibh; | |
182 | void *kaddr; | |
183 | int error; | |
184 | ||
fd88de56 SW |
185 | /* Only the first page of a stuffed file might contain data */ |
186 | if (unlikely(page->index)) | |
187 | return zero_readpage(page); | |
188 | ||
b3b94faa DT |
189 | error = gfs2_meta_inode_buffer(ip, &dibh); |
190 | if (error) | |
191 | return error; | |
192 | ||
5c4e9e03 | 193 | kaddr = kmap_atomic(page, KM_USER0); |
fd88de56 | 194 | memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), |
b3b94faa | 195 | ip->i_di.di_size); |
fd88de56 | 196 | memset(kaddr + ip->i_di.di_size, 0, PAGE_CACHE_SIZE - ip->i_di.di_size); |
5c4e9e03 | 197 | kunmap_atomic(page, KM_USER0); |
b3b94faa DT |
198 | |
199 | brelse(dibh); | |
200 | ||
201 | SetPageUptodate(page); | |
202 | ||
203 | return 0; | |
204 | } | |
205 | ||
b3b94faa | 206 | |
b3b94faa DT |
207 | /** |
208 | * gfs2_readpage - readpage with locking | |
18ec7d5c SW |
209 | * @file: The file to read a page for. N.B. This may be NULL if we are |
210 | * reading an internal file. | |
b3b94faa DT |
211 | * @page: The page to read |
212 | * | |
213 | * Returns: errno | |
214 | */ | |
215 | ||
216 | static int gfs2_readpage(struct file *file, struct page *page) | |
217 | { | |
feaa7bba SW |
218 | struct gfs2_inode *ip = GFS2_I(page->mapping->host); |
219 | struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host); | |
18ec7d5c | 220 | struct gfs2_holder gh; |
b3b94faa DT |
221 | int error; |
222 | ||
fd88de56 | 223 | if (likely(file != &gfs2_internal_file_sentinal)) { |
fe1bdedc | 224 | gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME|GL_AOP, &gh); |
61a30dcb | 225 | error = gfs2_glock_nq_m_atime(1, &gh); |
fd88de56 | 226 | if (unlikely(error)) |
61a30dcb SW |
227 | goto out_unlock; |
228 | } | |
b3b94faa | 229 | |
18ec7d5c | 230 | if (gfs2_is_stuffed(ip)) { |
fd88de56 SW |
231 | error = stuffed_readpage(ip, page); |
232 | unlock_page(page); | |
b3b94faa | 233 | } else |
18ec7d5c | 234 | error = mpage_readpage(page, gfs2_get_block); |
b3b94faa DT |
235 | |
236 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) | |
237 | error = -EIO; | |
238 | ||
61a30dcb SW |
239 | if (file != &gfs2_internal_file_sentinal) { |
240 | gfs2_glock_dq_m(1, &gh); | |
241 | gfs2_holder_uninit(&gh); | |
242 | } | |
18ec7d5c | 243 | out: |
b3b94faa | 244 | return error; |
18ec7d5c SW |
245 | out_unlock: |
246 | unlock_page(page); | |
fd88de56 SW |
247 | if (file != &gfs2_internal_file_sentinal) |
248 | gfs2_holder_uninit(&gh); | |
249 | goto out; | |
250 | } | |
251 | ||
fd88de56 SW |
252 | /** |
253 | * gfs2_readpages - Read a bunch of pages at once | |
254 | * | |
255 | * Some notes: | |
256 | * 1. This is only for readahead, so we can simply ignore any things | |
257 | * which are slightly inconvenient (such as locking conflicts between | |
258 | * the page lock and the glock) and return having done no I/O. Its | |
259 | * obviously not something we'd want to do on too regular a basis. | |
260 | * Any I/O we ignore at this time will be done via readpage later. | |
261 | * 2. We have to handle stuffed files here too. | |
262 | * 3. mpage_readpages() does most of the heavy lifting in the common case. | |
263 | * 4. gfs2_get_block() is relied upon to set BH_Boundary in the right places. | |
264 | * 5. We use LM_FLAG_TRY_1CB here, effectively we then have lock-ahead as | |
265 | * well as read-ahead. | |
266 | */ | |
267 | static int gfs2_readpages(struct file *file, struct address_space *mapping, | |
268 | struct list_head *pages, unsigned nr_pages) | |
269 | { | |
270 | struct inode *inode = mapping->host; | |
feaa7bba SW |
271 | struct gfs2_inode *ip = GFS2_I(inode); |
272 | struct gfs2_sbd *sdp = GFS2_SB(inode); | |
fd88de56 SW |
273 | struct gfs2_holder gh; |
274 | unsigned page_idx; | |
275 | int ret; | |
276 | ||
277 | if (likely(file != &gfs2_internal_file_sentinal)) { | |
278 | gfs2_holder_init(ip->i_gl, LM_ST_SHARED, | |
279 | LM_FLAG_TRY_1CB|GL_ATIME|GL_AOP, &gh); | |
280 | ret = gfs2_glock_nq_m_atime(1, &gh); | |
281 | if (ret == GLR_TRYFAILED) | |
282 | goto out_noerror; | |
283 | if (unlikely(ret)) | |
284 | goto out_unlock; | |
285 | } | |
286 | ||
287 | if (gfs2_is_stuffed(ip)) { | |
288 | struct pagevec lru_pvec; | |
289 | pagevec_init(&lru_pvec, 0); | |
290 | for (page_idx = 0; page_idx < nr_pages; page_idx++) { | |
ffeb874b SW |
291 | struct page *page = list_entry(pages->prev, struct page, lru); |
292 | prefetchw(&page->flags); | |
fd88de56 SW |
293 | list_del(&page->lru); |
294 | if (!add_to_page_cache(page, mapping, | |
295 | page->index, GFP_KERNEL)) { | |
296 | ret = stuffed_readpage(ip, page); | |
297 | unlock_page(page); | |
298 | if (!pagevec_add(&lru_pvec, page)) | |
299 | __pagevec_lru_add(&lru_pvec); | |
ffeb874b SW |
300 | } else { |
301 | page_cache_release(page); | |
fd88de56 | 302 | } |
fd88de56 SW |
303 | } |
304 | pagevec_lru_add(&lru_pvec); | |
305 | ret = 0; | |
306 | } else { | |
307 | /* What we really want to do .... */ | |
308 | ret = mpage_readpages(mapping, pages, nr_pages, gfs2_get_block); | |
309 | } | |
310 | ||
311 | if (likely(file != &gfs2_internal_file_sentinal)) { | |
312 | gfs2_glock_dq_m(1, &gh); | |
313 | gfs2_holder_uninit(&gh); | |
314 | } | |
315 | out: | |
316 | if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) | |
317 | ret = -EIO; | |
318 | return ret; | |
319 | out_noerror: | |
320 | ret = 0; | |
321 | out_unlock: | |
322 | /* unlock all pages, we can't do any I/O right now */ | |
323 | for (page_idx = 0; page_idx < nr_pages; page_idx++) { | |
ffeb874b | 324 | struct page *page = list_entry(pages->prev, struct page, lru); |
fd88de56 SW |
325 | list_del(&page->lru); |
326 | unlock_page(page); | |
327 | page_cache_release(page); | |
328 | } | |
329 | if (likely(file != &gfs2_internal_file_sentinal)) | |
330 | gfs2_holder_uninit(&gh); | |
18ec7d5c | 331 | goto out; |
b3b94faa DT |
332 | } |
333 | ||
334 | /** | |
335 | * gfs2_prepare_write - Prepare to write a page to a file | |
336 | * @file: The file to write to | |
337 | * @page: The page which is to be prepared for writing | |
338 | * @from: From (byte range within page) | |
339 | * @to: To (byte range within page) | |
340 | * | |
341 | * Returns: errno | |
342 | */ | |
343 | ||
344 | static int gfs2_prepare_write(struct file *file, struct page *page, | |
345 | unsigned from, unsigned to) | |
346 | { | |
feaa7bba SW |
347 | struct gfs2_inode *ip = GFS2_I(page->mapping->host); |
348 | struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host); | |
18ec7d5c SW |
349 | unsigned int data_blocks, ind_blocks, rblocks; |
350 | int alloc_required; | |
b3b94faa | 351 | int error = 0; |
18ec7d5c SW |
352 | loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + from; |
353 | loff_t end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; | |
354 | struct gfs2_alloc *al; | |
b3b94faa | 355 | |
fe1bdedc | 356 | gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME|GL_AOP, &ip->i_gh); |
18ec7d5c SW |
357 | error = gfs2_glock_nq_m_atime(1, &ip->i_gh); |
358 | if (error) | |
359 | goto out_uninit; | |
b3b94faa | 360 | |
18ec7d5c SW |
361 | gfs2_write_calc_reserv(ip, to - from, &data_blocks, &ind_blocks); |
362 | ||
363 | error = gfs2_write_alloc_required(ip, pos, from - to, &alloc_required); | |
364 | if (error) | |
365 | goto out_unlock; | |
b3b94faa | 366 | |
18ec7d5c SW |
367 | |
368 | if (alloc_required) { | |
369 | al = gfs2_alloc_get(ip); | |
370 | ||
371 | error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE); | |
372 | if (error) | |
373 | goto out_alloc_put; | |
374 | ||
375 | error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid); | |
376 | if (error) | |
377 | goto out_qunlock; | |
378 | ||
379 | al->al_requested = data_blocks + ind_blocks; | |
380 | error = gfs2_inplace_reserve(ip); | |
381 | if (error) | |
382 | goto out_qunlock; | |
383 | } | |
384 | ||
385 | rblocks = RES_DINODE + ind_blocks; | |
386 | if (gfs2_is_jdata(ip)) | |
387 | rblocks += data_blocks ? data_blocks : 1; | |
388 | if (ind_blocks || data_blocks) | |
389 | rblocks += RES_STATFS + RES_QUOTA; | |
390 | ||
391 | error = gfs2_trans_begin(sdp, rblocks, 0); | |
392 | if (error) | |
393 | goto out; | |
394 | ||
395 | if (gfs2_is_stuffed(ip)) { | |
396 | if (end > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) { | |
568f4c96 SW |
397 | error = gfs2_unstuff_dinode(ip, gfs2_unstuffer_page, |
398 | page); | |
5c4e9e03 SW |
399 | if (error == 0) |
400 | goto prepare_write; | |
401 | } else if (!PageUptodate(page)) | |
b3b94faa | 402 | error = stuffed_readpage(ip, page); |
5c4e9e03 | 403 | goto out; |
18ec7d5c SW |
404 | } |
405 | ||
5c4e9e03 | 406 | prepare_write: |
18ec7d5c SW |
407 | error = block_prepare_write(page, from, to, gfs2_get_block); |
408 | ||
409 | out: | |
410 | if (error) { | |
411 | gfs2_trans_end(sdp); | |
412 | if (alloc_required) { | |
413 | gfs2_inplace_release(ip); | |
414 | out_qunlock: | |
415 | gfs2_quota_unlock(ip); | |
416 | out_alloc_put: | |
417 | gfs2_alloc_put(ip); | |
418 | } | |
419 | out_unlock: | |
420 | gfs2_glock_dq_m(1, &ip->i_gh); | |
421 | out_uninit: | |
422 | gfs2_holder_uninit(&ip->i_gh); | |
423 | } | |
b3b94faa DT |
424 | |
425 | return error; | |
426 | } | |
427 | ||
428 | /** | |
429 | * gfs2_commit_write - Commit write to a file | |
430 | * @file: The file to write to | |
431 | * @page: The page containing the data | |
432 | * @from: From (byte range within page) | |
433 | * @to: To (byte range within page) | |
434 | * | |
435 | * Returns: errno | |
436 | */ | |
437 | ||
438 | static int gfs2_commit_write(struct file *file, struct page *page, | |
439 | unsigned from, unsigned to) | |
440 | { | |
441 | struct inode *inode = page->mapping->host; | |
feaa7bba SW |
442 | struct gfs2_inode *ip = GFS2_I(inode); |
443 | struct gfs2_sbd *sdp = GFS2_SB(inode); | |
18ec7d5c SW |
444 | int error = -EOPNOTSUPP; |
445 | struct buffer_head *dibh; | |
446 | struct gfs2_alloc *al = &ip->i_alloc;; | |
b3b94faa | 447 | |
18ec7d5c SW |
448 | if (gfs2_assert_withdraw(sdp, gfs2_glock_is_locked_by_me(ip->i_gl))) |
449 | goto fail_nounlock; | |
450 | ||
451 | error = gfs2_meta_inode_buffer(ip, &dibh); | |
452 | if (error) | |
453 | goto fail_endtrans; | |
454 | ||
455 | gfs2_trans_add_bh(ip->i_gl, dibh, 1); | |
456 | ||
b3b94faa | 457 | if (gfs2_is_stuffed(ip)) { |
b3b94faa DT |
458 | uint64_t file_size; |
459 | void *kaddr; | |
460 | ||
461 | file_size = ((uint64_t)page->index << PAGE_CACHE_SHIFT) + to; | |
462 | ||
18ec7d5c | 463 | kaddr = kmap_atomic(page, KM_USER0); |
b3b94faa | 464 | memcpy(dibh->b_data + sizeof(struct gfs2_dinode) + from, |
18ec7d5c SW |
465 | (char *)kaddr + from, to - from); |
466 | kunmap_atomic(page, KM_USER0); | |
b3b94faa DT |
467 | |
468 | SetPageUptodate(page); | |
469 | ||
470 | if (inode->i_size < file_size) | |
471 | i_size_write(inode, file_size); | |
472 | } else { | |
568f4c96 SW |
473 | if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || |
474 | gfs2_is_jdata(ip)) | |
257f9b4e | 475 | gfs2_page_add_databufs(ip, page, from, to); |
b3b94faa DT |
476 | error = generic_commit_write(file, page, from, to); |
477 | if (error) | |
478 | goto fail; | |
479 | } | |
480 | ||
18ec7d5c SW |
481 | if (ip->i_di.di_size < inode->i_size) |
482 | ip->i_di.di_size = inode->i_size; | |
483 | ||
484 | gfs2_dinode_out(&ip->i_di, dibh->b_data); | |
485 | brelse(dibh); | |
486 | gfs2_trans_end(sdp); | |
487 | if (al->al_requested) { | |
488 | gfs2_inplace_release(ip); | |
489 | gfs2_quota_unlock(ip); | |
490 | gfs2_alloc_put(ip); | |
491 | } | |
492 | gfs2_glock_dq_m(1, &ip->i_gh); | |
493 | gfs2_holder_uninit(&ip->i_gh); | |
b3b94faa DT |
494 | return 0; |
495 | ||
18ec7d5c SW |
496 | fail: |
497 | brelse(dibh); | |
498 | fail_endtrans: | |
499 | gfs2_trans_end(sdp); | |
500 | if (al->al_requested) { | |
501 | gfs2_inplace_release(ip); | |
502 | gfs2_quota_unlock(ip); | |
503 | gfs2_alloc_put(ip); | |
504 | } | |
505 | gfs2_glock_dq_m(1, &ip->i_gh); | |
506 | gfs2_holder_uninit(&ip->i_gh); | |
507 | fail_nounlock: | |
b3b94faa | 508 | ClearPageUptodate(page); |
b3b94faa DT |
509 | return error; |
510 | } | |
511 | ||
512 | /** | |
513 | * gfs2_bmap - Block map function | |
514 | * @mapping: Address space info | |
515 | * @lblock: The block to map | |
516 | * | |
517 | * Returns: The disk address for the block or 0 on hole or error | |
518 | */ | |
519 | ||
520 | static sector_t gfs2_bmap(struct address_space *mapping, sector_t lblock) | |
521 | { | |
feaa7bba | 522 | struct gfs2_inode *ip = GFS2_I(mapping->host); |
b3b94faa DT |
523 | struct gfs2_holder i_gh; |
524 | sector_t dblock = 0; | |
525 | int error; | |
526 | ||
b3b94faa DT |
527 | error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh); |
528 | if (error) | |
529 | return 0; | |
530 | ||
531 | if (!gfs2_is_stuffed(ip)) | |
4ff14670 | 532 | dblock = generic_block_bmap(mapping, lblock, gfs2_get_block); |
b3b94faa DT |
533 | |
534 | gfs2_glock_dq_uninit(&i_gh); | |
535 | ||
536 | return dblock; | |
537 | } | |
538 | ||
539 | static void discard_buffer(struct gfs2_sbd *sdp, struct buffer_head *bh) | |
540 | { | |
64fb4eb7 | 541 | struct gfs2_bufdata *bd; |
b3b94faa DT |
542 | |
543 | gfs2_log_lock(sdp); | |
5c676f6d | 544 | bd = bh->b_private; |
64fb4eb7 SW |
545 | if (bd) { |
546 | bd->bd_bh = NULL; | |
5c676f6d | 547 | bh->b_private = NULL; |
b3b94faa DT |
548 | gfs2_log_unlock(sdp); |
549 | brelse(bh); | |
550 | } else | |
551 | gfs2_log_unlock(sdp); | |
552 | ||
553 | lock_buffer(bh); | |
554 | clear_buffer_dirty(bh); | |
555 | bh->b_bdev = NULL; | |
556 | clear_buffer_mapped(bh); | |
557 | clear_buffer_req(bh); | |
558 | clear_buffer_new(bh); | |
559 | clear_buffer_delay(bh); | |
560 | unlock_buffer(bh); | |
561 | } | |
562 | ||
8628de05 | 563 | static void gfs2_invalidatepage(struct page *page, unsigned long offset) |
b3b94faa | 564 | { |
5c676f6d | 565 | struct gfs2_sbd *sdp = page->mapping->host->i_sb->s_fs_info; |
b3b94faa DT |
566 | struct buffer_head *head, *bh, *next; |
567 | unsigned int curr_off = 0; | |
b3b94faa DT |
568 | |
569 | BUG_ON(!PageLocked(page)); | |
570 | if (!page_has_buffers(page)) | |
8628de05 | 571 | return; |
b3b94faa DT |
572 | |
573 | bh = head = page_buffers(page); | |
574 | do { | |
575 | unsigned int next_off = curr_off + bh->b_size; | |
576 | next = bh->b_this_page; | |
577 | ||
578 | if (offset <= curr_off) | |
579 | discard_buffer(sdp, bh); | |
580 | ||
581 | curr_off = next_off; | |
582 | bh = next; | |
583 | } while (bh != head); | |
584 | ||
585 | if (!offset) | |
8628de05 | 586 | try_to_release_page(page, 0); |
b3b94faa | 587 | |
8628de05 | 588 | return; |
b3b94faa DT |
589 | } |
590 | ||
d1665e41 SW |
591 | static ssize_t gfs2_direct_IO_write(struct kiocb *iocb, const struct iovec *iov, |
592 | loff_t offset, unsigned long nr_segs) | |
593 | { | |
594 | struct file *file = iocb->ki_filp; | |
595 | struct inode *inode = file->f_mapping->host; | |
feaa7bba | 596 | struct gfs2_inode *ip = GFS2_I(inode); |
d1665e41 SW |
597 | struct gfs2_holder gh; |
598 | int rv; | |
599 | ||
600 | /* | |
601 | * Shared lock, even though its write, since we do no allocation | |
602 | * on this path. All we need change is atime. | |
603 | */ | |
604 | gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh); | |
605 | rv = gfs2_glock_nq_m_atime(1, &gh); | |
606 | if (rv) | |
607 | goto out; | |
608 | ||
609 | /* | |
610 | * Should we return an error here? I can't see that O_DIRECT for | |
611 | * a journaled file makes any sense. For now we'll silently fall | |
612 | * back to buffered I/O, likewise we do the same for stuffed | |
613 | * files since they are (a) small and (b) unaligned. | |
614 | */ | |
615 | if (gfs2_is_jdata(ip)) | |
616 | goto out; | |
617 | ||
618 | if (gfs2_is_stuffed(ip)) | |
619 | goto out; | |
620 | ||
621 | rv = __blockdev_direct_IO(WRITE, iocb, inode, inode->i_sb->s_bdev, | |
8628de05 | 622 | iov, offset, nr_segs, gfs2_get_block, |
d1665e41 SW |
623 | NULL, DIO_OWN_LOCKING); |
624 | out: | |
625 | gfs2_glock_dq_m(1, &gh); | |
626 | gfs2_holder_uninit(&gh); | |
627 | ||
628 | return rv; | |
629 | } | |
630 | ||
631 | /** | |
632 | * gfs2_direct_IO | |
633 | * | |
634 | * This is called with a shared lock already held for the read path. | |
635 | * Currently, no locks are held when the write path is called. | |
636 | */ | |
637 | static ssize_t gfs2_direct_IO(int rw, struct kiocb *iocb, | |
638 | const struct iovec *iov, loff_t offset, | |
639 | unsigned long nr_segs) | |
b3b94faa DT |
640 | { |
641 | struct file *file = iocb->ki_filp; | |
642 | struct inode *inode = file->f_mapping->host; | |
feaa7bba SW |
643 | struct gfs2_inode *ip = GFS2_I(inode); |
644 | struct gfs2_sbd *sdp = GFS2_SB(inode); | |
faac9bd0 | 645 | int ret; |
b3b94faa | 646 | |
d1665e41 SW |
647 | if (rw == WRITE) |
648 | return gfs2_direct_IO_write(iocb, iov, offset, nr_segs); | |
b3b94faa | 649 | |
d1665e41 SW |
650 | if (gfs2_assert_warn(sdp, gfs2_glock_is_locked_by_me(ip->i_gl)) || |
651 | gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip))) | |
652 | return -EINVAL; | |
b3b94faa | 653 | |
faac9bd0 SW |
654 | mutex_lock(&inode->i_mutex); |
655 | ret = __blockdev_direct_IO(READ, iocb, inode, inode->i_sb->s_bdev, iov, | |
656 | offset, nr_segs, gfs2_get_block, NULL, | |
657 | DIO_OWN_LOCKING); | |
658 | mutex_unlock(&inode->i_mutex); | |
659 | return ret; | |
b3b94faa DT |
660 | } |
661 | ||
66de045d | 662 | const struct address_space_operations gfs2_file_aops = { |
b3b94faa DT |
663 | .writepage = gfs2_writepage, |
664 | .readpage = gfs2_readpage, | |
fd88de56 | 665 | .readpages = gfs2_readpages, |
b3b94faa DT |
666 | .sync_page = block_sync_page, |
667 | .prepare_write = gfs2_prepare_write, | |
668 | .commit_write = gfs2_commit_write, | |
669 | .bmap = gfs2_bmap, | |
670 | .invalidatepage = gfs2_invalidatepage, | |
671 | .direct_IO = gfs2_direct_IO, | |
672 | }; | |
673 |