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Commit | Line | Data |
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1da177e4 | 1 | /* |
7b718769 NS |
2 | * Copyright (c) 2000-2005 Silicon Graphics, Inc. |
3 | * All Rights Reserved. | |
1da177e4 | 4 | * |
7b718769 NS |
5 | * This program is free software; you can redistribute it and/or |
6 | * modify it under the terms of the GNU General Public License as | |
1da177e4 LT |
7 | * published by the Free Software Foundation. |
8 | * | |
7b718769 NS |
9 | * This program is distributed in the hope that it would be useful, |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
1da177e4 | 13 | * |
7b718769 NS |
14 | * You should have received a copy of the GNU General Public License |
15 | * along with this program; if not, write the Free Software Foundation, | |
16 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
1da177e4 | 17 | */ |
1da177e4 | 18 | #include "xfs.h" |
a844f451 | 19 | #include "xfs_bit.h" |
1da177e4 | 20 | #include "xfs_log.h" |
a844f451 | 21 | #include "xfs_inum.h" |
1da177e4 | 22 | #include "xfs_sb.h" |
a844f451 | 23 | #include "xfs_ag.h" |
1da177e4 LT |
24 | #include "xfs_dir.h" |
25 | #include "xfs_dir2.h" | |
26 | #include "xfs_trans.h" | |
27 | #include "xfs_dmapi.h" | |
28 | #include "xfs_mount.h" | |
29 | #include "xfs_bmap_btree.h" | |
30 | #include "xfs_alloc_btree.h" | |
31 | #include "xfs_ialloc_btree.h" | |
1da177e4 LT |
32 | #include "xfs_dir_sf.h" |
33 | #include "xfs_dir2_sf.h" | |
a844f451 | 34 | #include "xfs_attr_sf.h" |
1da177e4 LT |
35 | #include "xfs_dinode.h" |
36 | #include "xfs_inode.h" | |
a844f451 NS |
37 | #include "xfs_alloc.h" |
38 | #include "xfs_btree.h" | |
1da177e4 LT |
39 | #include "xfs_error.h" |
40 | #include "xfs_rw.h" | |
41 | #include "xfs_iomap.h" | |
42 | #include <linux/mpage.h> | |
43 | #include <linux/writeback.h> | |
44 | ||
45 | STATIC void xfs_count_page_state(struct page *, int *, int *, int *); | |
46 | STATIC void xfs_convert_page(struct inode *, struct page *, xfs_iomap_t *, | |
47 | struct writeback_control *wbc, void *, int, int); | |
48 | ||
49 | #if defined(XFS_RW_TRACE) | |
50 | void | |
51 | xfs_page_trace( | |
52 | int tag, | |
53 | struct inode *inode, | |
54 | struct page *page, | |
55 | int mask) | |
56 | { | |
57 | xfs_inode_t *ip; | |
58 | bhv_desc_t *bdp; | |
59 | vnode_t *vp = LINVFS_GET_VP(inode); | |
60 | loff_t isize = i_size_read(inode); | |
61 | loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT; | |
62 | int delalloc = -1, unmapped = -1, unwritten = -1; | |
63 | ||
64 | if (page_has_buffers(page)) | |
65 | xfs_count_page_state(page, &delalloc, &unmapped, &unwritten); | |
66 | ||
67 | bdp = vn_bhv_lookup(VN_BHV_HEAD(vp), &xfs_vnodeops); | |
68 | ip = XFS_BHVTOI(bdp); | |
69 | if (!ip->i_rwtrace) | |
70 | return; | |
71 | ||
72 | ktrace_enter(ip->i_rwtrace, | |
73 | (void *)((unsigned long)tag), | |
74 | (void *)ip, | |
75 | (void *)inode, | |
76 | (void *)page, | |
77 | (void *)((unsigned long)mask), | |
78 | (void *)((unsigned long)((ip->i_d.di_size >> 32) & 0xffffffff)), | |
79 | (void *)((unsigned long)(ip->i_d.di_size & 0xffffffff)), | |
80 | (void *)((unsigned long)((isize >> 32) & 0xffffffff)), | |
81 | (void *)((unsigned long)(isize & 0xffffffff)), | |
82 | (void *)((unsigned long)((offset >> 32) & 0xffffffff)), | |
83 | (void *)((unsigned long)(offset & 0xffffffff)), | |
84 | (void *)((unsigned long)delalloc), | |
85 | (void *)((unsigned long)unmapped), | |
86 | (void *)((unsigned long)unwritten), | |
87 | (void *)NULL, | |
88 | (void *)NULL); | |
89 | } | |
90 | #else | |
91 | #define xfs_page_trace(tag, inode, page, mask) | |
92 | #endif | |
93 | ||
0829c360 CH |
94 | /* |
95 | * Schedule IO completion handling on a xfsdatad if this was | |
96 | * the final hold on this ioend. | |
97 | */ | |
98 | STATIC void | |
99 | xfs_finish_ioend( | |
100 | xfs_ioend_t *ioend) | |
101 | { | |
102 | if (atomic_dec_and_test(&ioend->io_remaining)) | |
103 | queue_work(xfsdatad_workqueue, &ioend->io_work); | |
104 | } | |
105 | ||
106 | STATIC void | |
107 | xfs_destroy_ioend( | |
108 | xfs_ioend_t *ioend) | |
109 | { | |
110 | vn_iowake(ioend->io_vnode); | |
111 | mempool_free(ioend, xfs_ioend_pool); | |
112 | } | |
113 | ||
114 | /* | |
115 | * Issue transactions to convert a buffer range from unwritten | |
f0973863 | 116 | * to written extents. |
0829c360 CH |
117 | */ |
118 | STATIC void | |
119 | xfs_end_bio_unwritten( | |
120 | void *data) | |
121 | { | |
122 | xfs_ioend_t *ioend = data; | |
123 | vnode_t *vp = ioend->io_vnode; | |
124 | xfs_off_t offset = ioend->io_offset; | |
125 | size_t size = ioend->io_size; | |
c1a073bd | 126 | struct buffer_head *bh, *next; |
0829c360 CH |
127 | int error; |
128 | ||
129 | if (ioend->io_uptodate) | |
130 | VOP_BMAP(vp, offset, size, BMAPI_UNWRITTEN, NULL, NULL, error); | |
c1a073bd CH |
131 | |
132 | /* ioend->io_buffer_head is only non-NULL for buffered I/O */ | |
133 | for (bh = ioend->io_buffer_head; bh; bh = next) { | |
134 | next = bh->b_private; | |
135 | ||
136 | bh->b_end_io = NULL; | |
137 | clear_buffer_unwritten(bh); | |
138 | end_buffer_async_write(bh, ioend->io_uptodate); | |
139 | } | |
140 | ||
0829c360 CH |
141 | xfs_destroy_ioend(ioend); |
142 | } | |
143 | ||
144 | /* | |
145 | * Allocate and initialise an IO completion structure. | |
146 | * We need to track unwritten extent write completion here initially. | |
147 | * We'll need to extend this for updating the ondisk inode size later | |
148 | * (vs. incore size). | |
149 | */ | |
150 | STATIC xfs_ioend_t * | |
151 | xfs_alloc_ioend( | |
152 | struct inode *inode) | |
153 | { | |
154 | xfs_ioend_t *ioend; | |
155 | ||
156 | ioend = mempool_alloc(xfs_ioend_pool, GFP_NOFS); | |
157 | ||
158 | /* | |
159 | * Set the count to 1 initially, which will prevent an I/O | |
160 | * completion callback from happening before we have started | |
161 | * all the I/O from calling the completion routine too early. | |
162 | */ | |
163 | atomic_set(&ioend->io_remaining, 1); | |
164 | ioend->io_uptodate = 1; /* cleared if any I/O fails */ | |
165 | ioend->io_vnode = LINVFS_GET_VP(inode); | |
c1a073bd | 166 | ioend->io_buffer_head = NULL; |
0829c360 CH |
167 | atomic_inc(&ioend->io_vnode->v_iocount); |
168 | ioend->io_offset = 0; | |
169 | ioend->io_size = 0; | |
170 | ||
171 | INIT_WORK(&ioend->io_work, xfs_end_bio_unwritten, ioend); | |
172 | ||
173 | return ioend; | |
174 | } | |
175 | ||
1da177e4 LT |
176 | void |
177 | linvfs_unwritten_done( | |
178 | struct buffer_head *bh, | |
179 | int uptodate) | |
180 | { | |
0829c360 | 181 | xfs_ioend_t *ioend = bh->b_private; |
c1a073bd CH |
182 | static spinlock_t unwritten_done_lock = SPIN_LOCK_UNLOCKED; |
183 | unsigned long flags; | |
1da177e4 LT |
184 | |
185 | ASSERT(buffer_unwritten(bh)); | |
186 | bh->b_end_io = NULL; | |
c1a073bd | 187 | |
1da177e4 | 188 | if (!uptodate) |
0829c360 | 189 | ioend->io_uptodate = 0; |
1da177e4 | 190 | |
c1a073bd CH |
191 | /* |
192 | * Deep magic here. We reuse b_private in the buffer_heads to build | |
193 | * a chain for completing the I/O from user context after we've issued | |
194 | * a transaction to convert the unwritten extent. | |
195 | */ | |
196 | spin_lock_irqsave(&unwritten_done_lock, flags); | |
197 | bh->b_private = ioend->io_buffer_head; | |
198 | ioend->io_buffer_head = bh; | |
199 | spin_unlock_irqrestore(&unwritten_done_lock, flags); | |
200 | ||
0829c360 | 201 | xfs_finish_ioend(ioend); |
1da177e4 LT |
202 | } |
203 | ||
1da177e4 LT |
204 | STATIC int |
205 | xfs_map_blocks( | |
206 | struct inode *inode, | |
207 | loff_t offset, | |
208 | ssize_t count, | |
209 | xfs_iomap_t *mapp, | |
210 | int flags) | |
211 | { | |
212 | vnode_t *vp = LINVFS_GET_VP(inode); | |
213 | int error, nmaps = 1; | |
214 | ||
215 | VOP_BMAP(vp, offset, count, flags, mapp, &nmaps, error); | |
216 | if (!error && (flags & (BMAPI_WRITE|BMAPI_ALLOCATE))) | |
217 | VMODIFY(vp); | |
218 | return -error; | |
219 | } | |
220 | ||
221 | /* | |
222 | * Finds the corresponding mapping in block @map array of the | |
223 | * given @offset within a @page. | |
224 | */ | |
225 | STATIC xfs_iomap_t * | |
226 | xfs_offset_to_map( | |
227 | struct page *page, | |
228 | xfs_iomap_t *iomapp, | |
229 | unsigned long offset) | |
230 | { | |
231 | loff_t full_offset; /* offset from start of file */ | |
232 | ||
233 | ASSERT(offset < PAGE_CACHE_SIZE); | |
234 | ||
235 | full_offset = page->index; /* NB: using 64bit number */ | |
236 | full_offset <<= PAGE_CACHE_SHIFT; /* offset from file start */ | |
237 | full_offset += offset; /* offset from page start */ | |
238 | ||
239 | if (full_offset < iomapp->iomap_offset) | |
240 | return NULL; | |
241 | if (iomapp->iomap_offset + (iomapp->iomap_bsize -1) >= full_offset) | |
242 | return iomapp; | |
243 | return NULL; | |
244 | } | |
245 | ||
246 | STATIC void | |
247 | xfs_map_at_offset( | |
248 | struct page *page, | |
249 | struct buffer_head *bh, | |
250 | unsigned long offset, | |
251 | int block_bits, | |
252 | xfs_iomap_t *iomapp) | |
253 | { | |
254 | xfs_daddr_t bn; | |
255 | loff_t delta; | |
256 | int sector_shift; | |
257 | ||
258 | ASSERT(!(iomapp->iomap_flags & IOMAP_HOLE)); | |
259 | ASSERT(!(iomapp->iomap_flags & IOMAP_DELAY)); | |
260 | ASSERT(iomapp->iomap_bn != IOMAP_DADDR_NULL); | |
261 | ||
262 | delta = page->index; | |
263 | delta <<= PAGE_CACHE_SHIFT; | |
264 | delta += offset; | |
265 | delta -= iomapp->iomap_offset; | |
266 | delta >>= block_bits; | |
267 | ||
268 | sector_shift = block_bits - BBSHIFT; | |
269 | bn = iomapp->iomap_bn >> sector_shift; | |
270 | bn += delta; | |
271 | BUG_ON(!bn && !(iomapp->iomap_flags & IOMAP_REALTIME)); | |
272 | ASSERT((bn << sector_shift) >= iomapp->iomap_bn); | |
273 | ||
274 | lock_buffer(bh); | |
275 | bh->b_blocknr = bn; | |
276 | bh->b_bdev = iomapp->iomap_target->pbr_bdev; | |
277 | set_buffer_mapped(bh); | |
278 | clear_buffer_delay(bh); | |
279 | } | |
280 | ||
281 | /* | |
282 | * Look for a page at index which is unlocked and contains our | |
283 | * unwritten extent flagged buffers at its head. Returns page | |
284 | * locked and with an extra reference count, and length of the | |
285 | * unwritten extent component on this page that we can write, | |
286 | * in units of filesystem blocks. | |
287 | */ | |
288 | STATIC struct page * | |
289 | xfs_probe_unwritten_page( | |
290 | struct address_space *mapping, | |
291 | pgoff_t index, | |
292 | xfs_iomap_t *iomapp, | |
0829c360 | 293 | xfs_ioend_t *ioend, |
1da177e4 LT |
294 | unsigned long max_offset, |
295 | unsigned long *fsbs, | |
296 | unsigned int bbits) | |
297 | { | |
298 | struct page *page; | |
299 | ||
300 | page = find_trylock_page(mapping, index); | |
301 | if (!page) | |
302 | return NULL; | |
303 | if (PageWriteback(page)) | |
304 | goto out; | |
305 | ||
306 | if (page->mapping && page_has_buffers(page)) { | |
307 | struct buffer_head *bh, *head; | |
308 | unsigned long p_offset = 0; | |
309 | ||
310 | *fsbs = 0; | |
311 | bh = head = page_buffers(page); | |
312 | do { | |
313 | if (!buffer_unwritten(bh) || !buffer_uptodate(bh)) | |
314 | break; | |
315 | if (!xfs_offset_to_map(page, iomapp, p_offset)) | |
316 | break; | |
317 | if (p_offset >= max_offset) | |
318 | break; | |
319 | xfs_map_at_offset(page, bh, p_offset, bbits, iomapp); | |
320 | set_buffer_unwritten_io(bh); | |
0829c360 | 321 | bh->b_private = ioend; |
1da177e4 LT |
322 | p_offset += bh->b_size; |
323 | (*fsbs)++; | |
324 | } while ((bh = bh->b_this_page) != head); | |
325 | ||
326 | if (p_offset) | |
327 | return page; | |
328 | } | |
329 | ||
330 | out: | |
331 | unlock_page(page); | |
332 | return NULL; | |
333 | } | |
334 | ||
335 | /* | |
336 | * Look for a page at index which is unlocked and not mapped | |
337 | * yet - clustering for mmap write case. | |
338 | */ | |
339 | STATIC unsigned int | |
340 | xfs_probe_unmapped_page( | |
341 | struct address_space *mapping, | |
342 | pgoff_t index, | |
343 | unsigned int pg_offset) | |
344 | { | |
345 | struct page *page; | |
346 | int ret = 0; | |
347 | ||
348 | page = find_trylock_page(mapping, index); | |
349 | if (!page) | |
350 | return 0; | |
351 | if (PageWriteback(page)) | |
352 | goto out; | |
353 | ||
354 | if (page->mapping && PageDirty(page)) { | |
355 | if (page_has_buffers(page)) { | |
356 | struct buffer_head *bh, *head; | |
357 | ||
358 | bh = head = page_buffers(page); | |
359 | do { | |
360 | if (buffer_mapped(bh) || !buffer_uptodate(bh)) | |
361 | break; | |
362 | ret += bh->b_size; | |
363 | if (ret >= pg_offset) | |
364 | break; | |
365 | } while ((bh = bh->b_this_page) != head); | |
366 | } else | |
367 | ret = PAGE_CACHE_SIZE; | |
368 | } | |
369 | ||
370 | out: | |
371 | unlock_page(page); | |
372 | return ret; | |
373 | } | |
374 | ||
375 | STATIC unsigned int | |
376 | xfs_probe_unmapped_cluster( | |
377 | struct inode *inode, | |
378 | struct page *startpage, | |
379 | struct buffer_head *bh, | |
380 | struct buffer_head *head) | |
381 | { | |
382 | pgoff_t tindex, tlast, tloff; | |
383 | unsigned int pg_offset, len, total = 0; | |
384 | struct address_space *mapping = inode->i_mapping; | |
385 | ||
386 | /* First sum forwards in this page */ | |
387 | do { | |
388 | if (buffer_mapped(bh)) | |
389 | break; | |
390 | total += bh->b_size; | |
391 | } while ((bh = bh->b_this_page) != head); | |
392 | ||
393 | /* If we reached the end of the page, sum forwards in | |
394 | * following pages. | |
395 | */ | |
396 | if (bh == head) { | |
397 | tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT; | |
398 | /* Prune this back to avoid pathological behavior */ | |
399 | tloff = min(tlast, startpage->index + 64); | |
400 | for (tindex = startpage->index + 1; tindex < tloff; tindex++) { | |
401 | len = xfs_probe_unmapped_page(mapping, tindex, | |
402 | PAGE_CACHE_SIZE); | |
403 | if (!len) | |
404 | return total; | |
405 | total += len; | |
406 | } | |
407 | if (tindex == tlast && | |
408 | (pg_offset = i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) { | |
409 | total += xfs_probe_unmapped_page(mapping, | |
410 | tindex, pg_offset); | |
411 | } | |
412 | } | |
413 | return total; | |
414 | } | |
415 | ||
416 | /* | |
417 | * Probe for a given page (index) in the inode and test if it is delayed | |
418 | * and without unwritten buffers. Returns page locked and with an extra | |
419 | * reference count. | |
420 | */ | |
421 | STATIC struct page * | |
422 | xfs_probe_delalloc_page( | |
423 | struct inode *inode, | |
424 | pgoff_t index) | |
425 | { | |
426 | struct page *page; | |
427 | ||
428 | page = find_trylock_page(inode->i_mapping, index); | |
429 | if (!page) | |
430 | return NULL; | |
431 | if (PageWriteback(page)) | |
432 | goto out; | |
433 | ||
434 | if (page->mapping && page_has_buffers(page)) { | |
435 | struct buffer_head *bh, *head; | |
436 | int acceptable = 0; | |
437 | ||
438 | bh = head = page_buffers(page); | |
439 | do { | |
440 | if (buffer_unwritten(bh)) { | |
441 | acceptable = 0; | |
442 | break; | |
443 | } else if (buffer_delay(bh)) { | |
444 | acceptable = 1; | |
445 | } | |
446 | } while ((bh = bh->b_this_page) != head); | |
447 | ||
448 | if (acceptable) | |
449 | return page; | |
450 | } | |
451 | ||
452 | out: | |
453 | unlock_page(page); | |
454 | return NULL; | |
455 | } | |
456 | ||
457 | STATIC int | |
458 | xfs_map_unwritten( | |
459 | struct inode *inode, | |
460 | struct page *start_page, | |
461 | struct buffer_head *head, | |
462 | struct buffer_head *curr, | |
463 | unsigned long p_offset, | |
464 | int block_bits, | |
465 | xfs_iomap_t *iomapp, | |
466 | struct writeback_control *wbc, | |
467 | int startio, | |
468 | int all_bh) | |
469 | { | |
470 | struct buffer_head *bh = curr; | |
471 | xfs_iomap_t *tmp; | |
0829c360 CH |
472 | xfs_ioend_t *ioend; |
473 | loff_t offset; | |
1da177e4 LT |
474 | unsigned long nblocks = 0; |
475 | ||
476 | offset = start_page->index; | |
477 | offset <<= PAGE_CACHE_SHIFT; | |
478 | offset += p_offset; | |
479 | ||
0829c360 | 480 | ioend = xfs_alloc_ioend(inode); |
1da177e4 LT |
481 | |
482 | /* First map forwards in the page consecutive buffers | |
483 | * covering this unwritten extent | |
484 | */ | |
485 | do { | |
486 | if (!buffer_unwritten(bh)) | |
487 | break; | |
488 | tmp = xfs_offset_to_map(start_page, iomapp, p_offset); | |
489 | if (!tmp) | |
490 | break; | |
491 | xfs_map_at_offset(start_page, bh, p_offset, block_bits, iomapp); | |
492 | set_buffer_unwritten_io(bh); | |
0829c360 | 493 | bh->b_private = ioend; |
1da177e4 LT |
494 | p_offset += bh->b_size; |
495 | nblocks++; | |
496 | } while ((bh = bh->b_this_page) != head); | |
497 | ||
0829c360 | 498 | atomic_add(nblocks, &ioend->io_remaining); |
1da177e4 LT |
499 | |
500 | /* If we reached the end of the page, map forwards in any | |
501 | * following pages which are also covered by this extent. | |
502 | */ | |
503 | if (bh == head) { | |
504 | struct address_space *mapping = inode->i_mapping; | |
505 | pgoff_t tindex, tloff, tlast; | |
506 | unsigned long bs; | |
507 | unsigned int pg_offset, bbits = inode->i_blkbits; | |
508 | struct page *page; | |
509 | ||
510 | tlast = i_size_read(inode) >> PAGE_CACHE_SHIFT; | |
511 | tloff = (iomapp->iomap_offset + iomapp->iomap_bsize) >> PAGE_CACHE_SHIFT; | |
512 | tloff = min(tlast, tloff); | |
513 | for (tindex = start_page->index + 1; tindex < tloff; tindex++) { | |
514 | page = xfs_probe_unwritten_page(mapping, | |
0829c360 | 515 | tindex, iomapp, ioend, |
1da177e4 LT |
516 | PAGE_CACHE_SIZE, &bs, bbits); |
517 | if (!page) | |
518 | break; | |
519 | nblocks += bs; | |
0829c360 CH |
520 | atomic_add(bs, &ioend->io_remaining); |
521 | xfs_convert_page(inode, page, iomapp, wbc, ioend, | |
1da177e4 LT |
522 | startio, all_bh); |
523 | /* stop if converting the next page might add | |
524 | * enough blocks that the corresponding byte | |
525 | * count won't fit in our ulong page buf length */ | |
526 | if (nblocks >= ((ULONG_MAX - PAGE_SIZE) >> block_bits)) | |
527 | goto enough; | |
528 | } | |
529 | ||
530 | if (tindex == tlast && | |
531 | (pg_offset = (i_size_read(inode) & (PAGE_CACHE_SIZE - 1)))) { | |
532 | page = xfs_probe_unwritten_page(mapping, | |
0829c360 | 533 | tindex, iomapp, ioend, |
1da177e4 LT |
534 | pg_offset, &bs, bbits); |
535 | if (page) { | |
536 | nblocks += bs; | |
0829c360 CH |
537 | atomic_add(bs, &ioend->io_remaining); |
538 | xfs_convert_page(inode, page, iomapp, wbc, ioend, | |
1da177e4 LT |
539 | startio, all_bh); |
540 | if (nblocks >= ((ULONG_MAX - PAGE_SIZE) >> block_bits)) | |
541 | goto enough; | |
542 | } | |
543 | } | |
544 | } | |
545 | ||
546 | enough: | |
0829c360 CH |
547 | ioend->io_size = (xfs_off_t)nblocks << block_bits; |
548 | ioend->io_offset = offset; | |
549 | xfs_finish_ioend(ioend); | |
1da177e4 LT |
550 | return 0; |
551 | } | |
552 | ||
553 | STATIC void | |
554 | xfs_submit_page( | |
555 | struct page *page, | |
556 | struct writeback_control *wbc, | |
557 | struct buffer_head *bh_arr[], | |
558 | int bh_count, | |
559 | int probed_page, | |
560 | int clear_dirty) | |
561 | { | |
562 | struct buffer_head *bh; | |
563 | int i; | |
564 | ||
565 | BUG_ON(PageWriteback(page)); | |
24e17b5f NS |
566 | if (bh_count) |
567 | set_page_writeback(page); | |
1da177e4 LT |
568 | if (clear_dirty) |
569 | clear_page_dirty(page); | |
570 | unlock_page(page); | |
571 | ||
572 | if (bh_count) { | |
573 | for (i = 0; i < bh_count; i++) { | |
574 | bh = bh_arr[i]; | |
575 | mark_buffer_async_write(bh); | |
576 | if (buffer_unwritten(bh)) | |
577 | set_buffer_unwritten_io(bh); | |
578 | set_buffer_uptodate(bh); | |
579 | clear_buffer_dirty(bh); | |
580 | } | |
581 | ||
582 | for (i = 0; i < bh_count; i++) | |
583 | submit_bh(WRITE, bh_arr[i]); | |
584 | ||
585 | if (probed_page && clear_dirty) | |
586 | wbc->nr_to_write--; /* Wrote an "extra" page */ | |
1da177e4 LT |
587 | } |
588 | } | |
589 | ||
590 | /* | |
591 | * Allocate & map buffers for page given the extent map. Write it out. | |
592 | * except for the original page of a writepage, this is called on | |
593 | * delalloc/unwritten pages only, for the original page it is possible | |
594 | * that the page has no mapping at all. | |
595 | */ | |
596 | STATIC void | |
597 | xfs_convert_page( | |
598 | struct inode *inode, | |
599 | struct page *page, | |
600 | xfs_iomap_t *iomapp, | |
601 | struct writeback_control *wbc, | |
602 | void *private, | |
603 | int startio, | |
604 | int all_bh) | |
605 | { | |
606 | struct buffer_head *bh_arr[MAX_BUF_PER_PAGE], *bh, *head; | |
607 | xfs_iomap_t *mp = iomapp, *tmp; | |
24e17b5f NS |
608 | unsigned long offset, end_offset; |
609 | int index = 0; | |
1da177e4 | 610 | int bbits = inode->i_blkbits; |
24e17b5f | 611 | int len, page_dirty; |
1da177e4 | 612 | |
24e17b5f NS |
613 | end_offset = (i_size_read(inode) & (PAGE_CACHE_SIZE - 1)); |
614 | ||
615 | /* | |
616 | * page_dirty is initially a count of buffers on the page before | |
617 | * EOF and is decrememted as we move each into a cleanable state. | |
618 | */ | |
619 | len = 1 << inode->i_blkbits; | |
620 | end_offset = max(end_offset, PAGE_CACHE_SIZE); | |
621 | end_offset = roundup(end_offset, len); | |
622 | page_dirty = end_offset / len; | |
623 | ||
624 | offset = 0; | |
1da177e4 LT |
625 | bh = head = page_buffers(page); |
626 | do { | |
24e17b5f | 627 | if (offset >= end_offset) |
1da177e4 LT |
628 | break; |
629 | if (!(PageUptodate(page) || buffer_uptodate(bh))) | |
630 | continue; | |
631 | if (buffer_mapped(bh) && all_bh && | |
632 | !(buffer_unwritten(bh) || buffer_delay(bh))) { | |
633 | if (startio) { | |
634 | lock_buffer(bh); | |
635 | bh_arr[index++] = bh; | |
24e17b5f | 636 | page_dirty--; |
1da177e4 LT |
637 | } |
638 | continue; | |
639 | } | |
640 | tmp = xfs_offset_to_map(page, mp, offset); | |
641 | if (!tmp) | |
642 | continue; | |
643 | ASSERT(!(tmp->iomap_flags & IOMAP_HOLE)); | |
644 | ASSERT(!(tmp->iomap_flags & IOMAP_DELAY)); | |
645 | ||
646 | /* If this is a new unwritten extent buffer (i.e. one | |
647 | * that we haven't passed in private data for, we must | |
648 | * now map this buffer too. | |
649 | */ | |
650 | if (buffer_unwritten(bh) && !bh->b_end_io) { | |
651 | ASSERT(tmp->iomap_flags & IOMAP_UNWRITTEN); | |
652 | xfs_map_unwritten(inode, page, head, bh, offset, | |
653 | bbits, tmp, wbc, startio, all_bh); | |
654 | } else if (! (buffer_unwritten(bh) && buffer_locked(bh))) { | |
655 | xfs_map_at_offset(page, bh, offset, bbits, tmp); | |
656 | if (buffer_unwritten(bh)) { | |
657 | set_buffer_unwritten_io(bh); | |
658 | bh->b_private = private; | |
659 | ASSERT(private); | |
660 | } | |
661 | } | |
662 | if (startio) { | |
663 | bh_arr[index++] = bh; | |
664 | } else { | |
665 | set_buffer_dirty(bh); | |
666 | unlock_buffer(bh); | |
667 | mark_buffer_dirty(bh); | |
668 | } | |
24e17b5f NS |
669 | page_dirty--; |
670 | } while (offset += len, (bh = bh->b_this_page) != head); | |
1da177e4 | 671 | |
24e17b5f NS |
672 | if (startio && index) { |
673 | xfs_submit_page(page, wbc, bh_arr, index, 1, !page_dirty); | |
1da177e4 LT |
674 | } else { |
675 | unlock_page(page); | |
676 | } | |
677 | } | |
678 | ||
679 | /* | |
680 | * Convert & write out a cluster of pages in the same extent as defined | |
681 | * by mp and following the start page. | |
682 | */ | |
683 | STATIC void | |
684 | xfs_cluster_write( | |
685 | struct inode *inode, | |
686 | pgoff_t tindex, | |
687 | xfs_iomap_t *iomapp, | |
688 | struct writeback_control *wbc, | |
689 | int startio, | |
690 | int all_bh, | |
691 | pgoff_t tlast) | |
692 | { | |
693 | struct page *page; | |
694 | ||
695 | for (; tindex <= tlast; tindex++) { | |
696 | page = xfs_probe_delalloc_page(inode, tindex); | |
697 | if (!page) | |
698 | break; | |
699 | xfs_convert_page(inode, page, iomapp, wbc, NULL, | |
700 | startio, all_bh); | |
701 | } | |
702 | } | |
703 | ||
704 | /* | |
705 | * Calling this without startio set means we are being asked to make a dirty | |
706 | * page ready for freeing it's buffers. When called with startio set then | |
707 | * we are coming from writepage. | |
708 | * | |
709 | * When called with startio set it is important that we write the WHOLE | |
710 | * page if possible. | |
711 | * The bh->b_state's cannot know if any of the blocks or which block for | |
712 | * that matter are dirty due to mmap writes, and therefore bh uptodate is | |
713 | * only vaild if the page itself isn't completely uptodate. Some layers | |
714 | * may clear the page dirty flag prior to calling write page, under the | |
715 | * assumption the entire page will be written out; by not writing out the | |
716 | * whole page the page can be reused before all valid dirty data is | |
717 | * written out. Note: in the case of a page that has been dirty'd by | |
718 | * mapwrite and but partially setup by block_prepare_write the | |
719 | * bh->b_states's will not agree and only ones setup by BPW/BCW will have | |
720 | * valid state, thus the whole page must be written out thing. | |
721 | */ | |
722 | ||
723 | STATIC int | |
724 | xfs_page_state_convert( | |
725 | struct inode *inode, | |
726 | struct page *page, | |
727 | struct writeback_control *wbc, | |
728 | int startio, | |
729 | int unmapped) /* also implies page uptodate */ | |
730 | { | |
731 | struct buffer_head *bh_arr[MAX_BUF_PER_PAGE], *bh, *head; | |
732 | xfs_iomap_t *iomp, iomap; | |
733 | loff_t offset; | |
734 | unsigned long p_offset = 0; | |
735 | __uint64_t end_offset; | |
736 | pgoff_t end_index, last_index, tlast; | |
737 | int len, err, i, cnt = 0, uptodate = 1; | |
3ba0815a | 738 | int flags; |
775bf6c9 | 739 | int page_dirty; |
1da177e4 | 740 | |
3ba0815a DM |
741 | /* wait for other IO threads? */ |
742 | flags = (startio && wbc->sync_mode != WB_SYNC_NONE) ? 0 : BMAPI_TRYLOCK; | |
743 | ||
1da177e4 LT |
744 | /* Is this page beyond the end of the file? */ |
745 | offset = i_size_read(inode); | |
746 | end_index = offset >> PAGE_CACHE_SHIFT; | |
747 | last_index = (offset - 1) >> PAGE_CACHE_SHIFT; | |
748 | if (page->index >= end_index) { | |
749 | if ((page->index >= end_index + 1) || | |
750 | !(i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) { | |
751 | err = -EIO; | |
752 | goto error; | |
753 | } | |
754 | } | |
755 | ||
1da177e4 | 756 | end_offset = min_t(unsigned long long, |
24e17b5f NS |
757 | (loff_t)(page->index + 1) << PAGE_CACHE_SHIFT, offset); |
758 | offset = (loff_t)page->index << PAGE_CACHE_SHIFT; | |
1da177e4 LT |
759 | |
760 | /* | |
24e17b5f NS |
761 | * page_dirty is initially a count of buffers on the page before |
762 | * EOF and is decrememted as we move each into a cleanable state. | |
1da177e4 | 763 | */ |
24e17b5f NS |
764 | len = 1 << inode->i_blkbits; |
765 | p_offset = max(p_offset, PAGE_CACHE_SIZE); | |
766 | p_offset = roundup(p_offset, len); | |
767 | page_dirty = p_offset / len; | |
768 | ||
769 | iomp = NULL; | |
770 | p_offset = 0; | |
771 | bh = head = page_buffers(page); | |
1da177e4 LT |
772 | |
773 | do { | |
774 | if (offset >= end_offset) | |
775 | break; | |
776 | if (!buffer_uptodate(bh)) | |
777 | uptodate = 0; | |
778 | if (!(PageUptodate(page) || buffer_uptodate(bh)) && !startio) | |
779 | continue; | |
780 | ||
781 | if (iomp) { | |
782 | iomp = xfs_offset_to_map(page, &iomap, p_offset); | |
783 | } | |
784 | ||
785 | /* | |
786 | * First case, map an unwritten extent and prepare for | |
787 | * extent state conversion transaction on completion. | |
788 | */ | |
789 | if (buffer_unwritten(bh)) { | |
790 | if (!startio) | |
791 | continue; | |
792 | if (!iomp) { | |
793 | err = xfs_map_blocks(inode, offset, len, &iomap, | |
c31e8878 | 794 | BMAPI_WRITE|BMAPI_IGNSTATE); |
1da177e4 LT |
795 | if (err) { |
796 | goto error; | |
797 | } | |
798 | iomp = xfs_offset_to_map(page, &iomap, | |
799 | p_offset); | |
800 | } | |
801 | if (iomp) { | |
802 | if (!bh->b_end_io) { | |
803 | err = xfs_map_unwritten(inode, page, | |
804 | head, bh, p_offset, | |
805 | inode->i_blkbits, iomp, | |
806 | wbc, startio, unmapped); | |
807 | if (err) { | |
808 | goto error; | |
809 | } | |
810 | } else { | |
811 | set_bit(BH_Lock, &bh->b_state); | |
812 | } | |
813 | BUG_ON(!buffer_locked(bh)); | |
814 | bh_arr[cnt++] = bh; | |
815 | page_dirty--; | |
816 | } | |
817 | /* | |
818 | * Second case, allocate space for a delalloc buffer. | |
819 | * We can return EAGAIN here in the release page case. | |
820 | */ | |
821 | } else if (buffer_delay(bh)) { | |
822 | if (!iomp) { | |
1da177e4 LT |
823 | err = xfs_map_blocks(inode, offset, len, &iomap, |
824 | BMAPI_ALLOCATE | flags); | |
825 | if (err) { | |
826 | goto error; | |
827 | } | |
828 | iomp = xfs_offset_to_map(page, &iomap, | |
829 | p_offset); | |
830 | } | |
831 | if (iomp) { | |
832 | xfs_map_at_offset(page, bh, p_offset, | |
833 | inode->i_blkbits, iomp); | |
834 | if (startio) { | |
835 | bh_arr[cnt++] = bh; | |
836 | } else { | |
837 | set_buffer_dirty(bh); | |
838 | unlock_buffer(bh); | |
839 | mark_buffer_dirty(bh); | |
840 | } | |
841 | page_dirty--; | |
842 | } | |
843 | } else if ((buffer_uptodate(bh) || PageUptodate(page)) && | |
844 | (unmapped || startio)) { | |
845 | ||
846 | if (!buffer_mapped(bh)) { | |
847 | int size; | |
848 | ||
849 | /* | |
850 | * Getting here implies an unmapped buffer | |
851 | * was found, and we are in a path where we | |
852 | * need to write the whole page out. | |
853 | */ | |
854 | if (!iomp) { | |
855 | size = xfs_probe_unmapped_cluster( | |
856 | inode, page, bh, head); | |
857 | err = xfs_map_blocks(inode, offset, | |
858 | size, &iomap, | |
859 | BMAPI_WRITE|BMAPI_MMAP); | |
860 | if (err) { | |
861 | goto error; | |
862 | } | |
863 | iomp = xfs_offset_to_map(page, &iomap, | |
864 | p_offset); | |
865 | } | |
866 | if (iomp) { | |
867 | xfs_map_at_offset(page, | |
868 | bh, p_offset, | |
869 | inode->i_blkbits, iomp); | |
870 | if (startio) { | |
871 | bh_arr[cnt++] = bh; | |
872 | } else { | |
873 | set_buffer_dirty(bh); | |
874 | unlock_buffer(bh); | |
875 | mark_buffer_dirty(bh); | |
876 | } | |
877 | page_dirty--; | |
878 | } | |
879 | } else if (startio) { | |
880 | if (buffer_uptodate(bh) && | |
881 | !test_and_set_bit(BH_Lock, &bh->b_state)) { | |
882 | bh_arr[cnt++] = bh; | |
883 | page_dirty--; | |
884 | } | |
885 | } | |
886 | } | |
887 | } while (offset += len, p_offset += len, | |
888 | ((bh = bh->b_this_page) != head)); | |
889 | ||
890 | if (uptodate && bh == head) | |
891 | SetPageUptodate(page); | |
892 | ||
24e17b5f | 893 | if (startio) { |
24e17b5f NS |
894 | xfs_submit_page(page, wbc, bh_arr, cnt, 0, !page_dirty); |
895 | } | |
1da177e4 LT |
896 | |
897 | if (iomp) { | |
775bf6c9 | 898 | offset = (iomp->iomap_offset + iomp->iomap_bsize - 1) >> |
1da177e4 | 899 | PAGE_CACHE_SHIFT; |
775bf6c9 | 900 | tlast = min_t(pgoff_t, offset, last_index); |
1da177e4 LT |
901 | xfs_cluster_write(inode, page->index + 1, iomp, wbc, |
902 | startio, unmapped, tlast); | |
903 | } | |
904 | ||
905 | return page_dirty; | |
906 | ||
907 | error: | |
908 | for (i = 0; i < cnt; i++) { | |
909 | unlock_buffer(bh_arr[i]); | |
910 | } | |
911 | ||
912 | /* | |
913 | * If it's delalloc and we have nowhere to put it, | |
914 | * throw it away, unless the lower layers told | |
915 | * us to try again. | |
916 | */ | |
917 | if (err != -EAGAIN) { | |
918 | if (!unmapped) { | |
919 | block_invalidatepage(page, 0); | |
920 | } | |
921 | ClearPageUptodate(page); | |
922 | } | |
923 | return err; | |
924 | } | |
925 | ||
926 | STATIC int | |
927 | __linvfs_get_block( | |
928 | struct inode *inode, | |
929 | sector_t iblock, | |
930 | unsigned long blocks, | |
931 | struct buffer_head *bh_result, | |
932 | int create, | |
933 | int direct, | |
934 | bmapi_flags_t flags) | |
935 | { | |
936 | vnode_t *vp = LINVFS_GET_VP(inode); | |
937 | xfs_iomap_t iomap; | |
fdc7ed75 NS |
938 | xfs_off_t offset; |
939 | ssize_t size; | |
1da177e4 LT |
940 | int retpbbm = 1; |
941 | int error; | |
1da177e4 | 942 | |
fdc7ed75 NS |
943 | if (blocks) { |
944 | offset = blocks << inode->i_blkbits; /* 64 bit goodness */ | |
945 | size = (ssize_t) min_t(xfs_off_t, offset, LONG_MAX); | |
946 | } else { | |
1da177e4 | 947 | size = 1 << inode->i_blkbits; |
fdc7ed75 NS |
948 | } |
949 | offset = (xfs_off_t)iblock << inode->i_blkbits; | |
1da177e4 LT |
950 | |
951 | VOP_BMAP(vp, offset, size, | |
952 | create ? flags : BMAPI_READ, &iomap, &retpbbm, error); | |
953 | if (error) | |
954 | return -error; | |
955 | ||
956 | if (retpbbm == 0) | |
957 | return 0; | |
958 | ||
959 | if (iomap.iomap_bn != IOMAP_DADDR_NULL) { | |
fdc7ed75 NS |
960 | xfs_daddr_t bn; |
961 | xfs_off_t delta; | |
1da177e4 LT |
962 | |
963 | /* For unwritten extents do not report a disk address on | |
964 | * the read case (treat as if we're reading into a hole). | |
965 | */ | |
966 | if (create || !(iomap.iomap_flags & IOMAP_UNWRITTEN)) { | |
967 | delta = offset - iomap.iomap_offset; | |
968 | delta >>= inode->i_blkbits; | |
969 | ||
970 | bn = iomap.iomap_bn >> (inode->i_blkbits - BBSHIFT); | |
971 | bn += delta; | |
972 | BUG_ON(!bn && !(iomap.iomap_flags & IOMAP_REALTIME)); | |
973 | bh_result->b_blocknr = bn; | |
974 | set_buffer_mapped(bh_result); | |
975 | } | |
976 | if (create && (iomap.iomap_flags & IOMAP_UNWRITTEN)) { | |
977 | if (direct) | |
978 | bh_result->b_private = inode; | |
979 | set_buffer_unwritten(bh_result); | |
980 | set_buffer_delay(bh_result); | |
981 | } | |
982 | } | |
983 | ||
984 | /* If this is a realtime file, data might be on a new device */ | |
985 | bh_result->b_bdev = iomap.iomap_target->pbr_bdev; | |
986 | ||
987 | /* If we previously allocated a block out beyond eof and | |
988 | * we are now coming back to use it then we will need to | |
989 | * flag it as new even if it has a disk address. | |
990 | */ | |
991 | if (create && | |
992 | ((!buffer_mapped(bh_result) && !buffer_uptodate(bh_result)) || | |
fdc7ed75 | 993 | (offset >= i_size_read(inode)) || (iomap.iomap_flags & IOMAP_NEW))) |
1da177e4 | 994 | set_buffer_new(bh_result); |
1da177e4 LT |
995 | |
996 | if (iomap.iomap_flags & IOMAP_DELAY) { | |
997 | BUG_ON(direct); | |
998 | if (create) { | |
999 | set_buffer_uptodate(bh_result); | |
1000 | set_buffer_mapped(bh_result); | |
1001 | set_buffer_delay(bh_result); | |
1002 | } | |
1003 | } | |
1004 | ||
1005 | if (blocks) { | |
fdc7ed75 NS |
1006 | ASSERT(iomap.iomap_bsize - iomap.iomap_delta > 0); |
1007 | offset = min_t(xfs_off_t, | |
1008 | iomap.iomap_bsize - iomap.iomap_delta, | |
1009 | blocks << inode->i_blkbits); | |
1010 | bh_result->b_size = (u32) min_t(xfs_off_t, UINT_MAX, offset); | |
1da177e4 LT |
1011 | } |
1012 | ||
1013 | return 0; | |
1014 | } | |
1015 | ||
1016 | int | |
1017 | linvfs_get_block( | |
1018 | struct inode *inode, | |
1019 | sector_t iblock, | |
1020 | struct buffer_head *bh_result, | |
1021 | int create) | |
1022 | { | |
1023 | return __linvfs_get_block(inode, iblock, 0, bh_result, | |
1024 | create, 0, BMAPI_WRITE); | |
1025 | } | |
1026 | ||
1027 | STATIC int | |
1028 | linvfs_get_blocks_direct( | |
1029 | struct inode *inode, | |
1030 | sector_t iblock, | |
1031 | unsigned long max_blocks, | |
1032 | struct buffer_head *bh_result, | |
1033 | int create) | |
1034 | { | |
1035 | return __linvfs_get_block(inode, iblock, max_blocks, bh_result, | |
1036 | create, 1, BMAPI_WRITE|BMAPI_DIRECT); | |
1037 | } | |
1038 | ||
f0973863 CH |
1039 | STATIC void |
1040 | linvfs_end_io_direct( | |
1041 | struct kiocb *iocb, | |
1042 | loff_t offset, | |
1043 | ssize_t size, | |
1044 | void *private) | |
1045 | { | |
1046 | xfs_ioend_t *ioend = iocb->private; | |
1047 | ||
1048 | /* | |
1049 | * Non-NULL private data means we need to issue a transaction to | |
1050 | * convert a range from unwritten to written extents. This needs | |
1051 | * to happen from process contect but aio+dio I/O completion | |
1052 | * happens from irq context so we need to defer it to a workqueue. | |
1053 | * This is not nessecary for synchronous direct I/O, but we do | |
1054 | * it anyway to keep the code uniform and simpler. | |
1055 | * | |
1056 | * The core direct I/O code might be changed to always call the | |
1057 | * completion handler in the future, in which case all this can | |
1058 | * go away. | |
1059 | */ | |
1060 | if (private && size > 0) { | |
1061 | ioend->io_offset = offset; | |
1062 | ioend->io_size = size; | |
1063 | xfs_finish_ioend(ioend); | |
1064 | } else { | |
1065 | ASSERT(size >= 0); | |
1066 | xfs_destroy_ioend(ioend); | |
1067 | } | |
1068 | ||
1069 | /* | |
1070 | * blockdev_direct_IO can return an error even afer the I/O | |
1071 | * completion handler was called. Thus we need to protect | |
1072 | * against double-freeing. | |
1073 | */ | |
1074 | iocb->private = NULL; | |
1075 | } | |
1076 | ||
1da177e4 LT |
1077 | STATIC ssize_t |
1078 | linvfs_direct_IO( | |
1079 | int rw, | |
1080 | struct kiocb *iocb, | |
1081 | const struct iovec *iov, | |
1082 | loff_t offset, | |
1083 | unsigned long nr_segs) | |
1084 | { | |
1085 | struct file *file = iocb->ki_filp; | |
1086 | struct inode *inode = file->f_mapping->host; | |
1087 | vnode_t *vp = LINVFS_GET_VP(inode); | |
1088 | xfs_iomap_t iomap; | |
1089 | int maps = 1; | |
1090 | int error; | |
f0973863 | 1091 | ssize_t ret; |
1da177e4 LT |
1092 | |
1093 | VOP_BMAP(vp, offset, 0, BMAPI_DEVICE, &iomap, &maps, error); | |
1094 | if (error) | |
1095 | return -error; | |
1096 | ||
f0973863 CH |
1097 | iocb->private = xfs_alloc_ioend(inode); |
1098 | ||
1099 | ret = blockdev_direct_IO_own_locking(rw, iocb, inode, | |
1da177e4 LT |
1100 | iomap.iomap_target->pbr_bdev, |
1101 | iov, offset, nr_segs, | |
1102 | linvfs_get_blocks_direct, | |
f0973863 CH |
1103 | linvfs_end_io_direct); |
1104 | ||
1105 | if (unlikely(ret <= 0 && iocb->private)) | |
1106 | xfs_destroy_ioend(iocb->private); | |
1107 | return ret; | |
1da177e4 LT |
1108 | } |
1109 | ||
1110 | ||
1111 | STATIC sector_t | |
1112 | linvfs_bmap( | |
1113 | struct address_space *mapping, | |
1114 | sector_t block) | |
1115 | { | |
1116 | struct inode *inode = (struct inode *)mapping->host; | |
1117 | vnode_t *vp = LINVFS_GET_VP(inode); | |
1118 | int error; | |
1119 | ||
1120 | vn_trace_entry(vp, "linvfs_bmap", (inst_t *)__return_address); | |
1121 | ||
1122 | VOP_RWLOCK(vp, VRWLOCK_READ); | |
1123 | VOP_FLUSH_PAGES(vp, (xfs_off_t)0, -1, 0, FI_REMAPF, error); | |
1124 | VOP_RWUNLOCK(vp, VRWLOCK_READ); | |
1125 | return generic_block_bmap(mapping, block, linvfs_get_block); | |
1126 | } | |
1127 | ||
1128 | STATIC int | |
1129 | linvfs_readpage( | |
1130 | struct file *unused, | |
1131 | struct page *page) | |
1132 | { | |
1133 | return mpage_readpage(page, linvfs_get_block); | |
1134 | } | |
1135 | ||
1136 | STATIC int | |
1137 | linvfs_readpages( | |
1138 | struct file *unused, | |
1139 | struct address_space *mapping, | |
1140 | struct list_head *pages, | |
1141 | unsigned nr_pages) | |
1142 | { | |
1143 | return mpage_readpages(mapping, pages, nr_pages, linvfs_get_block); | |
1144 | } | |
1145 | ||
1146 | STATIC void | |
1147 | xfs_count_page_state( | |
1148 | struct page *page, | |
1149 | int *delalloc, | |
1150 | int *unmapped, | |
1151 | int *unwritten) | |
1152 | { | |
1153 | struct buffer_head *bh, *head; | |
1154 | ||
1155 | *delalloc = *unmapped = *unwritten = 0; | |
1156 | ||
1157 | bh = head = page_buffers(page); | |
1158 | do { | |
1159 | if (buffer_uptodate(bh) && !buffer_mapped(bh)) | |
1160 | (*unmapped) = 1; | |
1161 | else if (buffer_unwritten(bh) && !buffer_delay(bh)) | |
1162 | clear_buffer_unwritten(bh); | |
1163 | else if (buffer_unwritten(bh)) | |
1164 | (*unwritten) = 1; | |
1165 | else if (buffer_delay(bh)) | |
1166 | (*delalloc) = 1; | |
1167 | } while ((bh = bh->b_this_page) != head); | |
1168 | } | |
1169 | ||
1170 | ||
1171 | /* | |
1172 | * writepage: Called from one of two places: | |
1173 | * | |
1174 | * 1. we are flushing a delalloc buffer head. | |
1175 | * | |
1176 | * 2. we are writing out a dirty page. Typically the page dirty | |
1177 | * state is cleared before we get here. In this case is it | |
1178 | * conceivable we have no buffer heads. | |
1179 | * | |
1180 | * For delalloc space on the page we need to allocate space and | |
1181 | * flush it. For unmapped buffer heads on the page we should | |
1182 | * allocate space if the page is uptodate. For any other dirty | |
1183 | * buffer heads on the page we should flush them. | |
1184 | * | |
1185 | * If we detect that a transaction would be required to flush | |
1186 | * the page, we have to check the process flags first, if we | |
1187 | * are already in a transaction or disk I/O during allocations | |
1188 | * is off, we need to fail the writepage and redirty the page. | |
1189 | */ | |
1190 | ||
1191 | STATIC int | |
1192 | linvfs_writepage( | |
1193 | struct page *page, | |
1194 | struct writeback_control *wbc) | |
1195 | { | |
1196 | int error; | |
1197 | int need_trans; | |
1198 | int delalloc, unmapped, unwritten; | |
1199 | struct inode *inode = page->mapping->host; | |
1200 | ||
1201 | xfs_page_trace(XFS_WRITEPAGE_ENTER, inode, page, 0); | |
1202 | ||
1203 | /* | |
1204 | * We need a transaction if: | |
1205 | * 1. There are delalloc buffers on the page | |
1206 | * 2. The page is uptodate and we have unmapped buffers | |
1207 | * 3. The page is uptodate and we have no buffers | |
1208 | * 4. There are unwritten buffers on the page | |
1209 | */ | |
1210 | ||
1211 | if (!page_has_buffers(page)) { | |
1212 | unmapped = 1; | |
1213 | need_trans = 1; | |
1214 | } else { | |
1215 | xfs_count_page_state(page, &delalloc, &unmapped, &unwritten); | |
1216 | if (!PageUptodate(page)) | |
1217 | unmapped = 0; | |
1218 | need_trans = delalloc + unmapped + unwritten; | |
1219 | } | |
1220 | ||
1221 | /* | |
1222 | * If we need a transaction and the process flags say | |
1223 | * we are already in a transaction, or no IO is allowed | |
1224 | * then mark the page dirty again and leave the page | |
1225 | * as is. | |
1226 | */ | |
1227 | if (PFLAGS_TEST_FSTRANS() && need_trans) | |
1228 | goto out_fail; | |
1229 | ||
1230 | /* | |
1231 | * Delay hooking up buffer heads until we have | |
1232 | * made our go/no-go decision. | |
1233 | */ | |
1234 | if (!page_has_buffers(page)) | |
1235 | create_empty_buffers(page, 1 << inode->i_blkbits, 0); | |
1236 | ||
1237 | /* | |
1238 | * Convert delayed allocate, unwritten or unmapped space | |
1239 | * to real space and flush out to disk. | |
1240 | */ | |
1241 | error = xfs_page_state_convert(inode, page, wbc, 1, unmapped); | |
1242 | if (error == -EAGAIN) | |
1243 | goto out_fail; | |
1244 | if (unlikely(error < 0)) | |
1245 | goto out_unlock; | |
1246 | ||
1247 | return 0; | |
1248 | ||
1249 | out_fail: | |
1250 | redirty_page_for_writepage(wbc, page); | |
1251 | unlock_page(page); | |
1252 | return 0; | |
1253 | out_unlock: | |
1254 | unlock_page(page); | |
1255 | return error; | |
1256 | } | |
1257 | ||
bcec2b7f NS |
1258 | STATIC int |
1259 | linvfs_invalidate_page( | |
1260 | struct page *page, | |
1261 | unsigned long offset) | |
1262 | { | |
1263 | xfs_page_trace(XFS_INVALIDPAGE_ENTER, | |
1264 | page->mapping->host, page, offset); | |
1265 | return block_invalidatepage(page, offset); | |
1266 | } | |
1267 | ||
1da177e4 LT |
1268 | /* |
1269 | * Called to move a page into cleanable state - and from there | |
1270 | * to be released. Possibly the page is already clean. We always | |
1271 | * have buffer heads in this call. | |
1272 | * | |
1273 | * Returns 0 if the page is ok to release, 1 otherwise. | |
1274 | * | |
1275 | * Possible scenarios are: | |
1276 | * | |
1277 | * 1. We are being called to release a page which has been written | |
1278 | * to via regular I/O. buffer heads will be dirty and possibly | |
1279 | * delalloc. If no delalloc buffer heads in this case then we | |
1280 | * can just return zero. | |
1281 | * | |
1282 | * 2. We are called to release a page which has been written via | |
1283 | * mmap, all we need to do is ensure there is no delalloc | |
1284 | * state in the buffer heads, if not we can let the caller | |
1285 | * free them and we should come back later via writepage. | |
1286 | */ | |
1287 | STATIC int | |
1288 | linvfs_release_page( | |
1289 | struct page *page, | |
27496a8c | 1290 | gfp_t gfp_mask) |
1da177e4 LT |
1291 | { |
1292 | struct inode *inode = page->mapping->host; | |
1293 | int dirty, delalloc, unmapped, unwritten; | |
1294 | struct writeback_control wbc = { | |
1295 | .sync_mode = WB_SYNC_ALL, | |
1296 | .nr_to_write = 1, | |
1297 | }; | |
1298 | ||
1299 | xfs_page_trace(XFS_RELEASEPAGE_ENTER, inode, page, gfp_mask); | |
1300 | ||
1301 | xfs_count_page_state(page, &delalloc, &unmapped, &unwritten); | |
1302 | if (!delalloc && !unwritten) | |
1303 | goto free_buffers; | |
1304 | ||
1305 | if (!(gfp_mask & __GFP_FS)) | |
1306 | return 0; | |
1307 | ||
1308 | /* If we are already inside a transaction or the thread cannot | |
1309 | * do I/O, we cannot release this page. | |
1310 | */ | |
1311 | if (PFLAGS_TEST_FSTRANS()) | |
1312 | return 0; | |
1313 | ||
1314 | /* | |
1315 | * Convert delalloc space to real space, do not flush the | |
1316 | * data out to disk, that will be done by the caller. | |
1317 | * Never need to allocate space here - we will always | |
1318 | * come back to writepage in that case. | |
1319 | */ | |
1320 | dirty = xfs_page_state_convert(inode, page, &wbc, 0, 0); | |
1321 | if (dirty == 0 && !unwritten) | |
1322 | goto free_buffers; | |
1323 | return 0; | |
1324 | ||
1325 | free_buffers: | |
1326 | return try_to_free_buffers(page); | |
1327 | } | |
1328 | ||
1329 | STATIC int | |
1330 | linvfs_prepare_write( | |
1331 | struct file *file, | |
1332 | struct page *page, | |
1333 | unsigned int from, | |
1334 | unsigned int to) | |
1335 | { | |
1336 | return block_prepare_write(page, from, to, linvfs_get_block); | |
1337 | } | |
1338 | ||
1339 | struct address_space_operations linvfs_aops = { | |
1340 | .readpage = linvfs_readpage, | |
1341 | .readpages = linvfs_readpages, | |
1342 | .writepage = linvfs_writepage, | |
1343 | .sync_page = block_sync_page, | |
1344 | .releasepage = linvfs_release_page, | |
bcec2b7f | 1345 | .invalidatepage = linvfs_invalidate_page, |
1da177e4 LT |
1346 | .prepare_write = linvfs_prepare_write, |
1347 | .commit_write = generic_commit_write, | |
1348 | .bmap = linvfs_bmap, | |
1349 | .direct_IO = linvfs_direct_IO, | |
1350 | }; |