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Commit | Line | Data |
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1 | /* | |
2 | * linux/fs/nfs/write.c | |
3 | * | |
4 | * Write file data over NFS. | |
5 | * | |
6 | * Copyright (C) 1996, 1997, Olaf Kirch <okir@monad.swb.de> | |
7 | */ | |
8 | ||
9 | #include <linux/types.h> | |
10 | #include <linux/slab.h> | |
11 | #include <linux/mm.h> | |
12 | #include <linux/pagemap.h> | |
13 | #include <linux/file.h> | |
14 | #include <linux/writeback.h> | |
15 | #include <linux/swap.h> | |
16 | #include <linux/migrate.h> | |
17 | ||
18 | #include <linux/sunrpc/clnt.h> | |
19 | #include <linux/nfs_fs.h> | |
20 | #include <linux/nfs_mount.h> | |
21 | #include <linux/nfs_page.h> | |
22 | #include <linux/backing-dev.h> | |
23 | ||
24 | #include <asm/uaccess.h> | |
25 | ||
26 | #include "delegation.h" | |
27 | #include "internal.h" | |
28 | #include "iostat.h" | |
29 | #include "nfs4_fs.h" | |
30 | #include "fscache.h" | |
31 | ||
32 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE | |
33 | ||
34 | #define MIN_POOL_WRITE (32) | |
35 | #define MIN_POOL_COMMIT (4) | |
36 | ||
37 | /* | |
38 | * Local function declarations | |
39 | */ | |
40 | static void nfs_pageio_init_write(struct nfs_pageio_descriptor *desc, | |
41 | struct inode *inode, int ioflags); | |
42 | static void nfs_redirty_request(struct nfs_page *req); | |
43 | static const struct rpc_call_ops nfs_write_partial_ops; | |
44 | static const struct rpc_call_ops nfs_write_full_ops; | |
45 | static const struct rpc_call_ops nfs_commit_ops; | |
46 | ||
47 | static struct kmem_cache *nfs_wdata_cachep; | |
48 | static mempool_t *nfs_wdata_mempool; | |
49 | static mempool_t *nfs_commit_mempool; | |
50 | ||
51 | struct nfs_write_data *nfs_commitdata_alloc(void) | |
52 | { | |
53 | struct nfs_write_data *p = mempool_alloc(nfs_commit_mempool, GFP_NOFS); | |
54 | ||
55 | if (p) { | |
56 | memset(p, 0, sizeof(*p)); | |
57 | INIT_LIST_HEAD(&p->pages); | |
58 | p->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE; | |
59 | } | |
60 | return p; | |
61 | } | |
62 | ||
63 | void nfs_commit_free(struct nfs_write_data *p) | |
64 | { | |
65 | if (p && (p->pagevec != &p->page_array[0])) | |
66 | kfree(p->pagevec); | |
67 | mempool_free(p, nfs_commit_mempool); | |
68 | } | |
69 | ||
70 | struct nfs_write_data *nfs_writedata_alloc(unsigned int pagecount) | |
71 | { | |
72 | struct nfs_write_data *p = mempool_alloc(nfs_wdata_mempool, GFP_NOFS); | |
73 | ||
74 | if (p) { | |
75 | memset(p, 0, sizeof(*p)); | |
76 | INIT_LIST_HEAD(&p->pages); | |
77 | p->npages = pagecount; | |
78 | p->res.seq_res.sr_slotid = NFS4_MAX_SLOT_TABLE; | |
79 | if (pagecount <= ARRAY_SIZE(p->page_array)) | |
80 | p->pagevec = p->page_array; | |
81 | else { | |
82 | p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_NOFS); | |
83 | if (!p->pagevec) { | |
84 | mempool_free(p, nfs_wdata_mempool); | |
85 | p = NULL; | |
86 | } | |
87 | } | |
88 | } | |
89 | return p; | |
90 | } | |
91 | ||
92 | void nfs_writedata_free(struct nfs_write_data *p) | |
93 | { | |
94 | if (p && (p->pagevec != &p->page_array[0])) | |
95 | kfree(p->pagevec); | |
96 | mempool_free(p, nfs_wdata_mempool); | |
97 | } | |
98 | ||
99 | static void nfs_writedata_release(struct nfs_write_data *wdata) | |
100 | { | |
101 | put_nfs_open_context(wdata->args.context); | |
102 | nfs_writedata_free(wdata); | |
103 | } | |
104 | ||
105 | static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error) | |
106 | { | |
107 | ctx->error = error; | |
108 | smp_wmb(); | |
109 | set_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); | |
110 | } | |
111 | ||
112 | static struct nfs_page *nfs_page_find_request_locked(struct page *page) | |
113 | { | |
114 | struct nfs_page *req = NULL; | |
115 | ||
116 | if (PagePrivate(page)) { | |
117 | req = (struct nfs_page *)page_private(page); | |
118 | if (req != NULL) | |
119 | kref_get(&req->wb_kref); | |
120 | } | |
121 | return req; | |
122 | } | |
123 | ||
124 | static struct nfs_page *nfs_page_find_request(struct page *page) | |
125 | { | |
126 | struct inode *inode = page->mapping->host; | |
127 | struct nfs_page *req = NULL; | |
128 | ||
129 | spin_lock(&inode->i_lock); | |
130 | req = nfs_page_find_request_locked(page); | |
131 | spin_unlock(&inode->i_lock); | |
132 | return req; | |
133 | } | |
134 | ||
135 | /* Adjust the file length if we're writing beyond the end */ | |
136 | static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count) | |
137 | { | |
138 | struct inode *inode = page->mapping->host; | |
139 | loff_t end, i_size; | |
140 | pgoff_t end_index; | |
141 | ||
142 | spin_lock(&inode->i_lock); | |
143 | i_size = i_size_read(inode); | |
144 | end_index = (i_size - 1) >> PAGE_CACHE_SHIFT; | |
145 | if (i_size > 0 && page->index < end_index) | |
146 | goto out; | |
147 | end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + ((loff_t)offset+count); | |
148 | if (i_size >= end) | |
149 | goto out; | |
150 | i_size_write(inode, end); | |
151 | nfs_inc_stats(inode, NFSIOS_EXTENDWRITE); | |
152 | out: | |
153 | spin_unlock(&inode->i_lock); | |
154 | } | |
155 | ||
156 | /* A writeback failed: mark the page as bad, and invalidate the page cache */ | |
157 | static void nfs_set_pageerror(struct page *page) | |
158 | { | |
159 | SetPageError(page); | |
160 | nfs_zap_mapping(page->mapping->host, page->mapping); | |
161 | } | |
162 | ||
163 | /* We can set the PG_uptodate flag if we see that a write request | |
164 | * covers the full page. | |
165 | */ | |
166 | static void nfs_mark_uptodate(struct page *page, unsigned int base, unsigned int count) | |
167 | { | |
168 | if (PageUptodate(page)) | |
169 | return; | |
170 | if (base != 0) | |
171 | return; | |
172 | if (count != nfs_page_length(page)) | |
173 | return; | |
174 | SetPageUptodate(page); | |
175 | } | |
176 | ||
177 | static int wb_priority(struct writeback_control *wbc) | |
178 | { | |
179 | if (wbc->for_reclaim) | |
180 | return FLUSH_HIGHPRI | FLUSH_STABLE; | |
181 | if (wbc->for_kupdate || wbc->for_background) | |
182 | return FLUSH_LOWPRI; | |
183 | return 0; | |
184 | } | |
185 | ||
186 | /* | |
187 | * NFS congestion control | |
188 | */ | |
189 | ||
190 | int nfs_congestion_kb; | |
191 | ||
192 | #define NFS_CONGESTION_ON_THRESH (nfs_congestion_kb >> (PAGE_SHIFT-10)) | |
193 | #define NFS_CONGESTION_OFF_THRESH \ | |
194 | (NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2)) | |
195 | ||
196 | static int nfs_set_page_writeback(struct page *page) | |
197 | { | |
198 | int ret = test_set_page_writeback(page); | |
199 | ||
200 | if (!ret) { | |
201 | struct inode *inode = page->mapping->host; | |
202 | struct nfs_server *nfss = NFS_SERVER(inode); | |
203 | ||
204 | page_cache_get(page); | |
205 | if (atomic_long_inc_return(&nfss->writeback) > | |
206 | NFS_CONGESTION_ON_THRESH) { | |
207 | set_bdi_congested(&nfss->backing_dev_info, | |
208 | BLK_RW_ASYNC); | |
209 | } | |
210 | } | |
211 | return ret; | |
212 | } | |
213 | ||
214 | static void nfs_end_page_writeback(struct page *page) | |
215 | { | |
216 | struct inode *inode = page->mapping->host; | |
217 | struct nfs_server *nfss = NFS_SERVER(inode); | |
218 | ||
219 | end_page_writeback(page); | |
220 | page_cache_release(page); | |
221 | if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) | |
222 | clear_bdi_congested(&nfss->backing_dev_info, BLK_RW_ASYNC); | |
223 | } | |
224 | ||
225 | static struct nfs_page *nfs_find_and_lock_request(struct page *page) | |
226 | { | |
227 | struct inode *inode = page->mapping->host; | |
228 | struct nfs_page *req; | |
229 | int ret; | |
230 | ||
231 | spin_lock(&inode->i_lock); | |
232 | for (;;) { | |
233 | req = nfs_page_find_request_locked(page); | |
234 | if (req == NULL) | |
235 | break; | |
236 | if (nfs_set_page_tag_locked(req)) | |
237 | break; | |
238 | /* Note: If we hold the page lock, as is the case in nfs_writepage, | |
239 | * then the call to nfs_set_page_tag_locked() will always | |
240 | * succeed provided that someone hasn't already marked the | |
241 | * request as dirty (in which case we don't care). | |
242 | */ | |
243 | spin_unlock(&inode->i_lock); | |
244 | ret = nfs_wait_on_request(req); | |
245 | nfs_release_request(req); | |
246 | if (ret != 0) | |
247 | return ERR_PTR(ret); | |
248 | spin_lock(&inode->i_lock); | |
249 | } | |
250 | spin_unlock(&inode->i_lock); | |
251 | return req; | |
252 | } | |
253 | ||
254 | /* | |
255 | * Find an associated nfs write request, and prepare to flush it out | |
256 | * May return an error if the user signalled nfs_wait_on_request(). | |
257 | */ | |
258 | static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio, | |
259 | struct page *page) | |
260 | { | |
261 | struct nfs_page *req; | |
262 | int ret = 0; | |
263 | ||
264 | req = nfs_find_and_lock_request(page); | |
265 | if (!req) | |
266 | goto out; | |
267 | ret = PTR_ERR(req); | |
268 | if (IS_ERR(req)) | |
269 | goto out; | |
270 | ||
271 | ret = nfs_set_page_writeback(page); | |
272 | BUG_ON(ret != 0); | |
273 | BUG_ON(test_bit(PG_CLEAN, &req->wb_flags)); | |
274 | ||
275 | if (!nfs_pageio_add_request(pgio, req)) { | |
276 | nfs_redirty_request(req); | |
277 | ret = pgio->pg_error; | |
278 | } | |
279 | out: | |
280 | return ret; | |
281 | } | |
282 | ||
283 | static int nfs_do_writepage(struct page *page, struct writeback_control *wbc, struct nfs_pageio_descriptor *pgio) | |
284 | { | |
285 | struct inode *inode = page->mapping->host; | |
286 | ||
287 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); | |
288 | nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1); | |
289 | ||
290 | nfs_pageio_cond_complete(pgio, page->index); | |
291 | return nfs_page_async_flush(pgio, page); | |
292 | } | |
293 | ||
294 | /* | |
295 | * Write an mmapped page to the server. | |
296 | */ | |
297 | static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc) | |
298 | { | |
299 | struct nfs_pageio_descriptor pgio; | |
300 | int err; | |
301 | ||
302 | nfs_pageio_init_write(&pgio, page->mapping->host, wb_priority(wbc)); | |
303 | err = nfs_do_writepage(page, wbc, &pgio); | |
304 | nfs_pageio_complete(&pgio); | |
305 | if (err < 0) | |
306 | return err; | |
307 | if (pgio.pg_error < 0) | |
308 | return pgio.pg_error; | |
309 | return 0; | |
310 | } | |
311 | ||
312 | int nfs_writepage(struct page *page, struct writeback_control *wbc) | |
313 | { | |
314 | int ret; | |
315 | ||
316 | ret = nfs_writepage_locked(page, wbc); | |
317 | unlock_page(page); | |
318 | return ret; | |
319 | } | |
320 | ||
321 | static int nfs_writepages_callback(struct page *page, struct writeback_control *wbc, void *data) | |
322 | { | |
323 | int ret; | |
324 | ||
325 | ret = nfs_do_writepage(page, wbc, data); | |
326 | unlock_page(page); | |
327 | return ret; | |
328 | } | |
329 | ||
330 | int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) | |
331 | { | |
332 | struct inode *inode = mapping->host; | |
333 | unsigned long *bitlock = &NFS_I(inode)->flags; | |
334 | struct nfs_pageio_descriptor pgio; | |
335 | int err; | |
336 | ||
337 | /* Stop dirtying of new pages while we sync */ | |
338 | err = wait_on_bit_lock(bitlock, NFS_INO_FLUSHING, | |
339 | nfs_wait_bit_killable, TASK_KILLABLE); | |
340 | if (err) | |
341 | goto out_err; | |
342 | ||
343 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); | |
344 | ||
345 | nfs_pageio_init_write(&pgio, inode, wb_priority(wbc)); | |
346 | err = write_cache_pages(mapping, wbc, nfs_writepages_callback, &pgio); | |
347 | nfs_pageio_complete(&pgio); | |
348 | ||
349 | clear_bit_unlock(NFS_INO_FLUSHING, bitlock); | |
350 | smp_mb__after_clear_bit(); | |
351 | wake_up_bit(bitlock, NFS_INO_FLUSHING); | |
352 | ||
353 | if (err < 0) | |
354 | goto out_err; | |
355 | err = pgio.pg_error; | |
356 | if (err < 0) | |
357 | goto out_err; | |
358 | return 0; | |
359 | out_err: | |
360 | return err; | |
361 | } | |
362 | ||
363 | /* | |
364 | * Insert a write request into an inode | |
365 | */ | |
366 | static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req) | |
367 | { | |
368 | struct nfs_inode *nfsi = NFS_I(inode); | |
369 | int error; | |
370 | ||
371 | error = radix_tree_preload(GFP_NOFS); | |
372 | if (error != 0) | |
373 | goto out; | |
374 | ||
375 | /* Lock the request! */ | |
376 | nfs_lock_request_dontget(req); | |
377 | ||
378 | spin_lock(&inode->i_lock); | |
379 | error = radix_tree_insert(&nfsi->nfs_page_tree, req->wb_index, req); | |
380 | BUG_ON(error); | |
381 | if (!nfsi->npages) { | |
382 | igrab(inode); | |
383 | if (nfs_have_delegation(inode, FMODE_WRITE)) | |
384 | nfsi->change_attr++; | |
385 | } | |
386 | SetPagePrivate(req->wb_page); | |
387 | set_page_private(req->wb_page, (unsigned long)req); | |
388 | nfsi->npages++; | |
389 | kref_get(&req->wb_kref); | |
390 | radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, | |
391 | NFS_PAGE_TAG_LOCKED); | |
392 | spin_unlock(&inode->i_lock); | |
393 | radix_tree_preload_end(); | |
394 | out: | |
395 | return error; | |
396 | } | |
397 | ||
398 | /* | |
399 | * Remove a write request from an inode | |
400 | */ | |
401 | static void nfs_inode_remove_request(struct nfs_page *req) | |
402 | { | |
403 | struct inode *inode = req->wb_context->path.dentry->d_inode; | |
404 | struct nfs_inode *nfsi = NFS_I(inode); | |
405 | ||
406 | BUG_ON (!NFS_WBACK_BUSY(req)); | |
407 | ||
408 | spin_lock(&inode->i_lock); | |
409 | set_page_private(req->wb_page, 0); | |
410 | ClearPagePrivate(req->wb_page); | |
411 | radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index); | |
412 | nfsi->npages--; | |
413 | if (!nfsi->npages) { | |
414 | spin_unlock(&inode->i_lock); | |
415 | iput(inode); | |
416 | } else | |
417 | spin_unlock(&inode->i_lock); | |
418 | nfs_clear_request(req); | |
419 | nfs_release_request(req); | |
420 | } | |
421 | ||
422 | static void | |
423 | nfs_mark_request_dirty(struct nfs_page *req) | |
424 | { | |
425 | __set_page_dirty_nobuffers(req->wb_page); | |
426 | __mark_inode_dirty(req->wb_page->mapping->host, I_DIRTY_DATASYNC); | |
427 | } | |
428 | ||
429 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
430 | /* | |
431 | * Add a request to the inode's commit list. | |
432 | */ | |
433 | static void | |
434 | nfs_mark_request_commit(struct nfs_page *req) | |
435 | { | |
436 | struct inode *inode = req->wb_context->path.dentry->d_inode; | |
437 | struct nfs_inode *nfsi = NFS_I(inode); | |
438 | ||
439 | spin_lock(&inode->i_lock); | |
440 | set_bit(PG_CLEAN, &(req)->wb_flags); | |
441 | radix_tree_tag_set(&nfsi->nfs_page_tree, | |
442 | req->wb_index, | |
443 | NFS_PAGE_TAG_COMMIT); | |
444 | nfsi->ncommit++; | |
445 | spin_unlock(&inode->i_lock); | |
446 | inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS); | |
447 | inc_bdi_stat(req->wb_page->mapping->backing_dev_info, BDI_RECLAIMABLE); | |
448 | __mark_inode_dirty(inode, I_DIRTY_DATASYNC); | |
449 | } | |
450 | ||
451 | static int | |
452 | nfs_clear_request_commit(struct nfs_page *req) | |
453 | { | |
454 | struct page *page = req->wb_page; | |
455 | ||
456 | if (test_and_clear_bit(PG_CLEAN, &(req)->wb_flags)) { | |
457 | dec_zone_page_state(page, NR_UNSTABLE_NFS); | |
458 | dec_bdi_stat(page->mapping->backing_dev_info, BDI_RECLAIMABLE); | |
459 | return 1; | |
460 | } | |
461 | return 0; | |
462 | } | |
463 | ||
464 | static inline | |
465 | int nfs_write_need_commit(struct nfs_write_data *data) | |
466 | { | |
467 | return data->verf.committed != NFS_FILE_SYNC; | |
468 | } | |
469 | ||
470 | static inline | |
471 | int nfs_reschedule_unstable_write(struct nfs_page *req) | |
472 | { | |
473 | if (test_and_clear_bit(PG_NEED_COMMIT, &req->wb_flags)) { | |
474 | nfs_mark_request_commit(req); | |
475 | return 1; | |
476 | } | |
477 | if (test_and_clear_bit(PG_NEED_RESCHED, &req->wb_flags)) { | |
478 | nfs_mark_request_dirty(req); | |
479 | return 1; | |
480 | } | |
481 | return 0; | |
482 | } | |
483 | #else | |
484 | static inline void | |
485 | nfs_mark_request_commit(struct nfs_page *req) | |
486 | { | |
487 | } | |
488 | ||
489 | static inline int | |
490 | nfs_clear_request_commit(struct nfs_page *req) | |
491 | { | |
492 | return 0; | |
493 | } | |
494 | ||
495 | static inline | |
496 | int nfs_write_need_commit(struct nfs_write_data *data) | |
497 | { | |
498 | return 0; | |
499 | } | |
500 | ||
501 | static inline | |
502 | int nfs_reschedule_unstable_write(struct nfs_page *req) | |
503 | { | |
504 | return 0; | |
505 | } | |
506 | #endif | |
507 | ||
508 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
509 | static int | |
510 | nfs_need_commit(struct nfs_inode *nfsi) | |
511 | { | |
512 | return radix_tree_tagged(&nfsi->nfs_page_tree, NFS_PAGE_TAG_COMMIT); | |
513 | } | |
514 | ||
515 | /* | |
516 | * nfs_scan_commit - Scan an inode for commit requests | |
517 | * @inode: NFS inode to scan | |
518 | * @dst: destination list | |
519 | * @idx_start: lower bound of page->index to scan. | |
520 | * @npages: idx_start + npages sets the upper bound to scan. | |
521 | * | |
522 | * Moves requests from the inode's 'commit' request list. | |
523 | * The requests are *not* checked to ensure that they form a contiguous set. | |
524 | */ | |
525 | static int | |
526 | nfs_scan_commit(struct inode *inode, struct list_head *dst, pgoff_t idx_start, unsigned int npages) | |
527 | { | |
528 | struct nfs_inode *nfsi = NFS_I(inode); | |
529 | int ret; | |
530 | ||
531 | if (!nfs_need_commit(nfsi)) | |
532 | return 0; | |
533 | ||
534 | ret = nfs_scan_list(nfsi, dst, idx_start, npages, NFS_PAGE_TAG_COMMIT); | |
535 | if (ret > 0) | |
536 | nfsi->ncommit -= ret; | |
537 | if (nfs_need_commit(NFS_I(inode))) | |
538 | __mark_inode_dirty(inode, I_DIRTY_DATASYNC); | |
539 | return ret; | |
540 | } | |
541 | #else | |
542 | static inline int nfs_need_commit(struct nfs_inode *nfsi) | |
543 | { | |
544 | return 0; | |
545 | } | |
546 | ||
547 | static inline int nfs_scan_commit(struct inode *inode, struct list_head *dst, pgoff_t idx_start, unsigned int npages) | |
548 | { | |
549 | return 0; | |
550 | } | |
551 | #endif | |
552 | ||
553 | /* | |
554 | * Search for an existing write request, and attempt to update | |
555 | * it to reflect a new dirty region on a given page. | |
556 | * | |
557 | * If the attempt fails, then the existing request is flushed out | |
558 | * to disk. | |
559 | */ | |
560 | static struct nfs_page *nfs_try_to_update_request(struct inode *inode, | |
561 | struct page *page, | |
562 | unsigned int offset, | |
563 | unsigned int bytes) | |
564 | { | |
565 | struct nfs_page *req; | |
566 | unsigned int rqend; | |
567 | unsigned int end; | |
568 | int error; | |
569 | ||
570 | if (!PagePrivate(page)) | |
571 | return NULL; | |
572 | ||
573 | end = offset + bytes; | |
574 | spin_lock(&inode->i_lock); | |
575 | ||
576 | for (;;) { | |
577 | req = nfs_page_find_request_locked(page); | |
578 | if (req == NULL) | |
579 | goto out_unlock; | |
580 | ||
581 | rqend = req->wb_offset + req->wb_bytes; | |
582 | /* | |
583 | * Tell the caller to flush out the request if | |
584 | * the offsets are non-contiguous. | |
585 | * Note: nfs_flush_incompatible() will already | |
586 | * have flushed out requests having wrong owners. | |
587 | */ | |
588 | if (offset > rqend | |
589 | || end < req->wb_offset) | |
590 | goto out_flushme; | |
591 | ||
592 | if (nfs_set_page_tag_locked(req)) | |
593 | break; | |
594 | ||
595 | /* The request is locked, so wait and then retry */ | |
596 | spin_unlock(&inode->i_lock); | |
597 | error = nfs_wait_on_request(req); | |
598 | nfs_release_request(req); | |
599 | if (error != 0) | |
600 | goto out_err; | |
601 | spin_lock(&inode->i_lock); | |
602 | } | |
603 | ||
604 | if (nfs_clear_request_commit(req) && | |
605 | radix_tree_tag_clear(&NFS_I(inode)->nfs_page_tree, | |
606 | req->wb_index, NFS_PAGE_TAG_COMMIT) != NULL) | |
607 | NFS_I(inode)->ncommit--; | |
608 | ||
609 | /* Okay, the request matches. Update the region */ | |
610 | if (offset < req->wb_offset) { | |
611 | req->wb_offset = offset; | |
612 | req->wb_pgbase = offset; | |
613 | } | |
614 | if (end > rqend) | |
615 | req->wb_bytes = end - req->wb_offset; | |
616 | else | |
617 | req->wb_bytes = rqend - req->wb_offset; | |
618 | out_unlock: | |
619 | spin_unlock(&inode->i_lock); | |
620 | return req; | |
621 | out_flushme: | |
622 | spin_unlock(&inode->i_lock); | |
623 | nfs_release_request(req); | |
624 | error = nfs_wb_page(inode, page); | |
625 | out_err: | |
626 | return ERR_PTR(error); | |
627 | } | |
628 | ||
629 | /* | |
630 | * Try to update an existing write request, or create one if there is none. | |
631 | * | |
632 | * Note: Should always be called with the Page Lock held to prevent races | |
633 | * if we have to add a new request. Also assumes that the caller has | |
634 | * already called nfs_flush_incompatible() if necessary. | |
635 | */ | |
636 | static struct nfs_page * nfs_setup_write_request(struct nfs_open_context* ctx, | |
637 | struct page *page, unsigned int offset, unsigned int bytes) | |
638 | { | |
639 | struct inode *inode = page->mapping->host; | |
640 | struct nfs_page *req; | |
641 | int error; | |
642 | ||
643 | req = nfs_try_to_update_request(inode, page, offset, bytes); | |
644 | if (req != NULL) | |
645 | goto out; | |
646 | req = nfs_create_request(ctx, inode, page, offset, bytes); | |
647 | if (IS_ERR(req)) | |
648 | goto out; | |
649 | error = nfs_inode_add_request(inode, req); | |
650 | if (error != 0) { | |
651 | nfs_release_request(req); | |
652 | req = ERR_PTR(error); | |
653 | } | |
654 | out: | |
655 | return req; | |
656 | } | |
657 | ||
658 | static int nfs_writepage_setup(struct nfs_open_context *ctx, struct page *page, | |
659 | unsigned int offset, unsigned int count) | |
660 | { | |
661 | struct nfs_page *req; | |
662 | ||
663 | req = nfs_setup_write_request(ctx, page, offset, count); | |
664 | if (IS_ERR(req)) | |
665 | return PTR_ERR(req); | |
666 | nfs_mark_request_dirty(req); | |
667 | /* Update file length */ | |
668 | nfs_grow_file(page, offset, count); | |
669 | nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes); | |
670 | nfs_mark_request_dirty(req); | |
671 | nfs_clear_page_tag_locked(req); | |
672 | return 0; | |
673 | } | |
674 | ||
675 | int nfs_flush_incompatible(struct file *file, struct page *page) | |
676 | { | |
677 | struct nfs_open_context *ctx = nfs_file_open_context(file); | |
678 | struct nfs_page *req; | |
679 | int do_flush, status; | |
680 | /* | |
681 | * Look for a request corresponding to this page. If there | |
682 | * is one, and it belongs to another file, we flush it out | |
683 | * before we try to copy anything into the page. Do this | |
684 | * due to the lack of an ACCESS-type call in NFSv2. | |
685 | * Also do the same if we find a request from an existing | |
686 | * dropped page. | |
687 | */ | |
688 | do { | |
689 | req = nfs_page_find_request(page); | |
690 | if (req == NULL) | |
691 | return 0; | |
692 | do_flush = req->wb_page != page || req->wb_context != ctx; | |
693 | nfs_release_request(req); | |
694 | if (!do_flush) | |
695 | return 0; | |
696 | status = nfs_wb_page(page->mapping->host, page); | |
697 | } while (status == 0); | |
698 | return status; | |
699 | } | |
700 | ||
701 | /* | |
702 | * If the page cache is marked as unsafe or invalid, then we can't rely on | |
703 | * the PageUptodate() flag. In this case, we will need to turn off | |
704 | * write optimisations that depend on the page contents being correct. | |
705 | */ | |
706 | static int nfs_write_pageuptodate(struct page *page, struct inode *inode) | |
707 | { | |
708 | return PageUptodate(page) && | |
709 | !(NFS_I(inode)->cache_validity & (NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA)); | |
710 | } | |
711 | ||
712 | /* | |
713 | * Update and possibly write a cached page of an NFS file. | |
714 | * | |
715 | * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad | |
716 | * things with a page scheduled for an RPC call (e.g. invalidate it). | |
717 | */ | |
718 | int nfs_updatepage(struct file *file, struct page *page, | |
719 | unsigned int offset, unsigned int count) | |
720 | { | |
721 | struct nfs_open_context *ctx = nfs_file_open_context(file); | |
722 | struct inode *inode = page->mapping->host; | |
723 | int status = 0; | |
724 | ||
725 | nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE); | |
726 | ||
727 | dprintk("NFS: nfs_updatepage(%s/%s %d@%lld)\n", | |
728 | file->f_path.dentry->d_parent->d_name.name, | |
729 | file->f_path.dentry->d_name.name, count, | |
730 | (long long)(page_offset(page) + offset)); | |
731 | ||
732 | /* If we're not using byte range locks, and we know the page | |
733 | * is up to date, it may be more efficient to extend the write | |
734 | * to cover the entire page in order to avoid fragmentation | |
735 | * inefficiencies. | |
736 | */ | |
737 | if (nfs_write_pageuptodate(page, inode) && | |
738 | inode->i_flock == NULL && | |
739 | !(file->f_flags & O_DSYNC)) { | |
740 | count = max(count + offset, nfs_page_length(page)); | |
741 | offset = 0; | |
742 | } | |
743 | ||
744 | status = nfs_writepage_setup(ctx, page, offset, count); | |
745 | if (status < 0) | |
746 | nfs_set_pageerror(page); | |
747 | ||
748 | dprintk("NFS: nfs_updatepage returns %d (isize %lld)\n", | |
749 | status, (long long)i_size_read(inode)); | |
750 | return status; | |
751 | } | |
752 | ||
753 | static void nfs_writepage_release(struct nfs_page *req) | |
754 | { | |
755 | struct page *page = req->wb_page; | |
756 | ||
757 | if (PageError(req->wb_page) || !nfs_reschedule_unstable_write(req)) | |
758 | nfs_inode_remove_request(req); | |
759 | nfs_clear_page_tag_locked(req); | |
760 | nfs_end_page_writeback(page); | |
761 | } | |
762 | ||
763 | static int flush_task_priority(int how) | |
764 | { | |
765 | switch (how & (FLUSH_HIGHPRI|FLUSH_LOWPRI)) { | |
766 | case FLUSH_HIGHPRI: | |
767 | return RPC_PRIORITY_HIGH; | |
768 | case FLUSH_LOWPRI: | |
769 | return RPC_PRIORITY_LOW; | |
770 | } | |
771 | return RPC_PRIORITY_NORMAL; | |
772 | } | |
773 | ||
774 | /* | |
775 | * Set up the argument/result storage required for the RPC call. | |
776 | */ | |
777 | static int nfs_write_rpcsetup(struct nfs_page *req, | |
778 | struct nfs_write_data *data, | |
779 | const struct rpc_call_ops *call_ops, | |
780 | unsigned int count, unsigned int offset, | |
781 | int how) | |
782 | { | |
783 | struct inode *inode = req->wb_context->path.dentry->d_inode; | |
784 | int priority = flush_task_priority(how); | |
785 | struct rpc_task *task; | |
786 | struct rpc_message msg = { | |
787 | .rpc_argp = &data->args, | |
788 | .rpc_resp = &data->res, | |
789 | .rpc_cred = req->wb_context->cred, | |
790 | }; | |
791 | struct rpc_task_setup task_setup_data = { | |
792 | .rpc_client = NFS_CLIENT(inode), | |
793 | .task = &data->task, | |
794 | .rpc_message = &msg, | |
795 | .callback_ops = call_ops, | |
796 | .callback_data = data, | |
797 | .workqueue = nfsiod_workqueue, | |
798 | .flags = RPC_TASK_ASYNC, | |
799 | .priority = priority, | |
800 | }; | |
801 | int ret = 0; | |
802 | ||
803 | /* Set up the RPC argument and reply structs | |
804 | * NB: take care not to mess about with data->commit et al. */ | |
805 | ||
806 | data->req = req; | |
807 | data->inode = inode = req->wb_context->path.dentry->d_inode; | |
808 | data->cred = msg.rpc_cred; | |
809 | ||
810 | data->args.fh = NFS_FH(inode); | |
811 | data->args.offset = req_offset(req) + offset; | |
812 | data->args.pgbase = req->wb_pgbase + offset; | |
813 | data->args.pages = data->pagevec; | |
814 | data->args.count = count; | |
815 | data->args.context = get_nfs_open_context(req->wb_context); | |
816 | data->args.stable = NFS_UNSTABLE; | |
817 | if (how & FLUSH_STABLE) { | |
818 | data->args.stable = NFS_DATA_SYNC; | |
819 | if (!nfs_need_commit(NFS_I(inode))) | |
820 | data->args.stable = NFS_FILE_SYNC; | |
821 | } | |
822 | ||
823 | data->res.fattr = &data->fattr; | |
824 | data->res.count = count; | |
825 | data->res.verf = &data->verf; | |
826 | nfs_fattr_init(&data->fattr); | |
827 | ||
828 | /* Set up the initial task struct. */ | |
829 | NFS_PROTO(inode)->write_setup(data, &msg); | |
830 | ||
831 | dprintk("NFS: %5u initiated write call " | |
832 | "(req %s/%lld, %u bytes @ offset %llu)\n", | |
833 | data->task.tk_pid, | |
834 | inode->i_sb->s_id, | |
835 | (long long)NFS_FILEID(inode), | |
836 | count, | |
837 | (unsigned long long)data->args.offset); | |
838 | ||
839 | task = rpc_run_task(&task_setup_data); | |
840 | if (IS_ERR(task)) { | |
841 | ret = PTR_ERR(task); | |
842 | goto out; | |
843 | } | |
844 | if (how & FLUSH_SYNC) { | |
845 | ret = rpc_wait_for_completion_task(task); | |
846 | if (ret == 0) | |
847 | ret = task->tk_status; | |
848 | } | |
849 | rpc_put_task(task); | |
850 | out: | |
851 | return ret; | |
852 | } | |
853 | ||
854 | /* If a nfs_flush_* function fails, it should remove reqs from @head and | |
855 | * call this on each, which will prepare them to be retried on next | |
856 | * writeback using standard nfs. | |
857 | */ | |
858 | static void nfs_redirty_request(struct nfs_page *req) | |
859 | { | |
860 | struct page *page = req->wb_page; | |
861 | ||
862 | nfs_mark_request_dirty(req); | |
863 | nfs_clear_page_tag_locked(req); | |
864 | nfs_end_page_writeback(page); | |
865 | } | |
866 | ||
867 | /* | |
868 | * Generate multiple small requests to write out a single | |
869 | * contiguous dirty area on one page. | |
870 | */ | |
871 | static int nfs_flush_multi(struct inode *inode, struct list_head *head, unsigned int npages, size_t count, int how) | |
872 | { | |
873 | struct nfs_page *req = nfs_list_entry(head->next); | |
874 | struct page *page = req->wb_page; | |
875 | struct nfs_write_data *data; | |
876 | size_t wsize = NFS_SERVER(inode)->wsize, nbytes; | |
877 | unsigned int offset; | |
878 | int requests = 0; | |
879 | int ret = 0; | |
880 | LIST_HEAD(list); | |
881 | ||
882 | nfs_list_remove_request(req); | |
883 | ||
884 | nbytes = count; | |
885 | do { | |
886 | size_t len = min(nbytes, wsize); | |
887 | ||
888 | data = nfs_writedata_alloc(1); | |
889 | if (!data) | |
890 | goto out_bad; | |
891 | list_add(&data->pages, &list); | |
892 | requests++; | |
893 | nbytes -= len; | |
894 | } while (nbytes != 0); | |
895 | atomic_set(&req->wb_complete, requests); | |
896 | ||
897 | ClearPageError(page); | |
898 | offset = 0; | |
899 | nbytes = count; | |
900 | do { | |
901 | int ret2; | |
902 | ||
903 | data = list_entry(list.next, struct nfs_write_data, pages); | |
904 | list_del_init(&data->pages); | |
905 | ||
906 | data->pagevec[0] = page; | |
907 | ||
908 | if (nbytes < wsize) | |
909 | wsize = nbytes; | |
910 | ret2 = nfs_write_rpcsetup(req, data, &nfs_write_partial_ops, | |
911 | wsize, offset, how); | |
912 | if (ret == 0) | |
913 | ret = ret2; | |
914 | offset += wsize; | |
915 | nbytes -= wsize; | |
916 | } while (nbytes != 0); | |
917 | ||
918 | return ret; | |
919 | ||
920 | out_bad: | |
921 | while (!list_empty(&list)) { | |
922 | data = list_entry(list.next, struct nfs_write_data, pages); | |
923 | list_del(&data->pages); | |
924 | nfs_writedata_release(data); | |
925 | } | |
926 | nfs_redirty_request(req); | |
927 | return -ENOMEM; | |
928 | } | |
929 | ||
930 | /* | |
931 | * Create an RPC task for the given write request and kick it. | |
932 | * The page must have been locked by the caller. | |
933 | * | |
934 | * It may happen that the page we're passed is not marked dirty. | |
935 | * This is the case if nfs_updatepage detects a conflicting request | |
936 | * that has been written but not committed. | |
937 | */ | |
938 | static int nfs_flush_one(struct inode *inode, struct list_head *head, unsigned int npages, size_t count, int how) | |
939 | { | |
940 | struct nfs_page *req; | |
941 | struct page **pages; | |
942 | struct nfs_write_data *data; | |
943 | ||
944 | data = nfs_writedata_alloc(npages); | |
945 | if (!data) | |
946 | goto out_bad; | |
947 | ||
948 | pages = data->pagevec; | |
949 | while (!list_empty(head)) { | |
950 | req = nfs_list_entry(head->next); | |
951 | nfs_list_remove_request(req); | |
952 | nfs_list_add_request(req, &data->pages); | |
953 | ClearPageError(req->wb_page); | |
954 | *pages++ = req->wb_page; | |
955 | } | |
956 | req = nfs_list_entry(data->pages.next); | |
957 | ||
958 | /* Set up the argument struct */ | |
959 | return nfs_write_rpcsetup(req, data, &nfs_write_full_ops, count, 0, how); | |
960 | out_bad: | |
961 | while (!list_empty(head)) { | |
962 | req = nfs_list_entry(head->next); | |
963 | nfs_list_remove_request(req); | |
964 | nfs_redirty_request(req); | |
965 | } | |
966 | return -ENOMEM; | |
967 | } | |
968 | ||
969 | static void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, | |
970 | struct inode *inode, int ioflags) | |
971 | { | |
972 | size_t wsize = NFS_SERVER(inode)->wsize; | |
973 | ||
974 | if (wsize < PAGE_CACHE_SIZE) | |
975 | nfs_pageio_init(pgio, inode, nfs_flush_multi, wsize, ioflags); | |
976 | else | |
977 | nfs_pageio_init(pgio, inode, nfs_flush_one, wsize, ioflags); | |
978 | } | |
979 | ||
980 | /* | |
981 | * Handle a write reply that flushed part of a page. | |
982 | */ | |
983 | static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata) | |
984 | { | |
985 | struct nfs_write_data *data = calldata; | |
986 | ||
987 | dprintk("NFS: %5u write(%s/%lld %d@%lld)", | |
988 | task->tk_pid, | |
989 | data->req->wb_context->path.dentry->d_inode->i_sb->s_id, | |
990 | (long long) | |
991 | NFS_FILEID(data->req->wb_context->path.dentry->d_inode), | |
992 | data->req->wb_bytes, (long long)req_offset(data->req)); | |
993 | ||
994 | nfs_writeback_done(task, data); | |
995 | } | |
996 | ||
997 | static void nfs_writeback_release_partial(void *calldata) | |
998 | { | |
999 | struct nfs_write_data *data = calldata; | |
1000 | struct nfs_page *req = data->req; | |
1001 | struct page *page = req->wb_page; | |
1002 | int status = data->task.tk_status; | |
1003 | ||
1004 | if (status < 0) { | |
1005 | nfs_set_pageerror(page); | |
1006 | nfs_context_set_write_error(req->wb_context, status); | |
1007 | dprintk(", error = %d\n", status); | |
1008 | goto out; | |
1009 | } | |
1010 | ||
1011 | if (nfs_write_need_commit(data)) { | |
1012 | struct inode *inode = page->mapping->host; | |
1013 | ||
1014 | spin_lock(&inode->i_lock); | |
1015 | if (test_bit(PG_NEED_RESCHED, &req->wb_flags)) { | |
1016 | /* Do nothing we need to resend the writes */ | |
1017 | } else if (!test_and_set_bit(PG_NEED_COMMIT, &req->wb_flags)) { | |
1018 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1019 | dprintk(" defer commit\n"); | |
1020 | } else if (memcmp(&req->wb_verf, &data->verf, sizeof(req->wb_verf))) { | |
1021 | set_bit(PG_NEED_RESCHED, &req->wb_flags); | |
1022 | clear_bit(PG_NEED_COMMIT, &req->wb_flags); | |
1023 | dprintk(" server reboot detected\n"); | |
1024 | } | |
1025 | spin_unlock(&inode->i_lock); | |
1026 | } else | |
1027 | dprintk(" OK\n"); | |
1028 | ||
1029 | out: | |
1030 | if (atomic_dec_and_test(&req->wb_complete)) | |
1031 | nfs_writepage_release(req); | |
1032 | nfs_writedata_release(calldata); | |
1033 | } | |
1034 | ||
1035 | #if defined(CONFIG_NFS_V4_1) | |
1036 | void nfs_write_prepare(struct rpc_task *task, void *calldata) | |
1037 | { | |
1038 | struct nfs_write_data *data = calldata; | |
1039 | struct nfs_client *clp = (NFS_SERVER(data->inode))->nfs_client; | |
1040 | ||
1041 | if (nfs4_setup_sequence(clp, &data->args.seq_args, | |
1042 | &data->res.seq_res, 1, task)) | |
1043 | return; | |
1044 | rpc_call_start(task); | |
1045 | } | |
1046 | #endif /* CONFIG_NFS_V4_1 */ | |
1047 | ||
1048 | static const struct rpc_call_ops nfs_write_partial_ops = { | |
1049 | #if defined(CONFIG_NFS_V4_1) | |
1050 | .rpc_call_prepare = nfs_write_prepare, | |
1051 | #endif /* CONFIG_NFS_V4_1 */ | |
1052 | .rpc_call_done = nfs_writeback_done_partial, | |
1053 | .rpc_release = nfs_writeback_release_partial, | |
1054 | }; | |
1055 | ||
1056 | /* | |
1057 | * Handle a write reply that flushes a whole page. | |
1058 | * | |
1059 | * FIXME: There is an inherent race with invalidate_inode_pages and | |
1060 | * writebacks since the page->count is kept > 1 for as long | |
1061 | * as the page has a write request pending. | |
1062 | */ | |
1063 | static void nfs_writeback_done_full(struct rpc_task *task, void *calldata) | |
1064 | { | |
1065 | struct nfs_write_data *data = calldata; | |
1066 | ||
1067 | nfs_writeback_done(task, data); | |
1068 | } | |
1069 | ||
1070 | static void nfs_writeback_release_full(void *calldata) | |
1071 | { | |
1072 | struct nfs_write_data *data = calldata; | |
1073 | int status = data->task.tk_status; | |
1074 | ||
1075 | /* Update attributes as result of writeback. */ | |
1076 | while (!list_empty(&data->pages)) { | |
1077 | struct nfs_page *req = nfs_list_entry(data->pages.next); | |
1078 | struct page *page = req->wb_page; | |
1079 | ||
1080 | nfs_list_remove_request(req); | |
1081 | ||
1082 | dprintk("NFS: %5u write (%s/%lld %d@%lld)", | |
1083 | data->task.tk_pid, | |
1084 | req->wb_context->path.dentry->d_inode->i_sb->s_id, | |
1085 | (long long)NFS_FILEID(req->wb_context->path.dentry->d_inode), | |
1086 | req->wb_bytes, | |
1087 | (long long)req_offset(req)); | |
1088 | ||
1089 | if (status < 0) { | |
1090 | nfs_set_pageerror(page); | |
1091 | nfs_context_set_write_error(req->wb_context, status); | |
1092 | dprintk(", error = %d\n", status); | |
1093 | goto remove_request; | |
1094 | } | |
1095 | ||
1096 | if (nfs_write_need_commit(data)) { | |
1097 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1098 | nfs_mark_request_commit(req); | |
1099 | dprintk(" marked for commit\n"); | |
1100 | goto next; | |
1101 | } | |
1102 | dprintk(" OK\n"); | |
1103 | remove_request: | |
1104 | nfs_inode_remove_request(req); | |
1105 | next: | |
1106 | nfs_clear_page_tag_locked(req); | |
1107 | nfs_end_page_writeback(page); | |
1108 | } | |
1109 | nfs_writedata_release(calldata); | |
1110 | } | |
1111 | ||
1112 | static const struct rpc_call_ops nfs_write_full_ops = { | |
1113 | #if defined(CONFIG_NFS_V4_1) | |
1114 | .rpc_call_prepare = nfs_write_prepare, | |
1115 | #endif /* CONFIG_NFS_V4_1 */ | |
1116 | .rpc_call_done = nfs_writeback_done_full, | |
1117 | .rpc_release = nfs_writeback_release_full, | |
1118 | }; | |
1119 | ||
1120 | ||
1121 | /* | |
1122 | * This function is called when the WRITE call is complete. | |
1123 | */ | |
1124 | int nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data) | |
1125 | { | |
1126 | struct nfs_writeargs *argp = &data->args; | |
1127 | struct nfs_writeres *resp = &data->res; | |
1128 | struct nfs_server *server = NFS_SERVER(data->inode); | |
1129 | int status; | |
1130 | ||
1131 | dprintk("NFS: %5u nfs_writeback_done (status %d)\n", | |
1132 | task->tk_pid, task->tk_status); | |
1133 | ||
1134 | /* | |
1135 | * ->write_done will attempt to use post-op attributes to detect | |
1136 | * conflicting writes by other clients. A strict interpretation | |
1137 | * of close-to-open would allow us to continue caching even if | |
1138 | * another writer had changed the file, but some applications | |
1139 | * depend on tighter cache coherency when writing. | |
1140 | */ | |
1141 | status = NFS_PROTO(data->inode)->write_done(task, data); | |
1142 | if (status != 0) | |
1143 | return status; | |
1144 | nfs_add_stats(data->inode, NFSIOS_SERVERWRITTENBYTES, resp->count); | |
1145 | ||
1146 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1147 | if (resp->verf->committed < argp->stable && task->tk_status >= 0) { | |
1148 | /* We tried a write call, but the server did not | |
1149 | * commit data to stable storage even though we | |
1150 | * requested it. | |
1151 | * Note: There is a known bug in Tru64 < 5.0 in which | |
1152 | * the server reports NFS_DATA_SYNC, but performs | |
1153 | * NFS_FILE_SYNC. We therefore implement this checking | |
1154 | * as a dprintk() in order to avoid filling syslog. | |
1155 | */ | |
1156 | static unsigned long complain; | |
1157 | ||
1158 | if (time_before(complain, jiffies)) { | |
1159 | dprintk("NFS: faulty NFS server %s:" | |
1160 | " (committed = %d) != (stable = %d)\n", | |
1161 | server->nfs_client->cl_hostname, | |
1162 | resp->verf->committed, argp->stable); | |
1163 | complain = jiffies + 300 * HZ; | |
1164 | } | |
1165 | } | |
1166 | #endif | |
1167 | /* Is this a short write? */ | |
1168 | if (task->tk_status >= 0 && resp->count < argp->count) { | |
1169 | static unsigned long complain; | |
1170 | ||
1171 | nfs_inc_stats(data->inode, NFSIOS_SHORTWRITE); | |
1172 | ||
1173 | /* Has the server at least made some progress? */ | |
1174 | if (resp->count != 0) { | |
1175 | /* Was this an NFSv2 write or an NFSv3 stable write? */ | |
1176 | if (resp->verf->committed != NFS_UNSTABLE) { | |
1177 | /* Resend from where the server left off */ | |
1178 | argp->offset += resp->count; | |
1179 | argp->pgbase += resp->count; | |
1180 | argp->count -= resp->count; | |
1181 | } else { | |
1182 | /* Resend as a stable write in order to avoid | |
1183 | * headaches in the case of a server crash. | |
1184 | */ | |
1185 | argp->stable = NFS_FILE_SYNC; | |
1186 | } | |
1187 | nfs_restart_rpc(task, server->nfs_client); | |
1188 | return -EAGAIN; | |
1189 | } | |
1190 | if (time_before(complain, jiffies)) { | |
1191 | printk(KERN_WARNING | |
1192 | "NFS: Server wrote zero bytes, expected %u.\n", | |
1193 | argp->count); | |
1194 | complain = jiffies + 300 * HZ; | |
1195 | } | |
1196 | /* Can't do anything about it except throw an error. */ | |
1197 | task->tk_status = -EIO; | |
1198 | } | |
1199 | return 0; | |
1200 | } | |
1201 | ||
1202 | ||
1203 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1204 | static int nfs_commit_set_lock(struct nfs_inode *nfsi, int may_wait) | |
1205 | { | |
1206 | if (!test_and_set_bit(NFS_INO_COMMIT, &nfsi->flags)) | |
1207 | return 1; | |
1208 | if (may_wait && !out_of_line_wait_on_bit_lock(&nfsi->flags, | |
1209 | NFS_INO_COMMIT, nfs_wait_bit_killable, | |
1210 | TASK_KILLABLE)) | |
1211 | return 1; | |
1212 | return 0; | |
1213 | } | |
1214 | ||
1215 | static void nfs_commit_clear_lock(struct nfs_inode *nfsi) | |
1216 | { | |
1217 | clear_bit(NFS_INO_COMMIT, &nfsi->flags); | |
1218 | smp_mb__after_clear_bit(); | |
1219 | wake_up_bit(&nfsi->flags, NFS_INO_COMMIT); | |
1220 | } | |
1221 | ||
1222 | ||
1223 | static void nfs_commitdata_release(void *data) | |
1224 | { | |
1225 | struct nfs_write_data *wdata = data; | |
1226 | ||
1227 | put_nfs_open_context(wdata->args.context); | |
1228 | nfs_commit_free(wdata); | |
1229 | } | |
1230 | ||
1231 | /* | |
1232 | * Set up the argument/result storage required for the RPC call. | |
1233 | */ | |
1234 | static int nfs_commit_rpcsetup(struct list_head *head, | |
1235 | struct nfs_write_data *data, | |
1236 | int how) | |
1237 | { | |
1238 | struct nfs_page *first = nfs_list_entry(head->next); | |
1239 | struct inode *inode = first->wb_context->path.dentry->d_inode; | |
1240 | int priority = flush_task_priority(how); | |
1241 | struct rpc_task *task; | |
1242 | struct rpc_message msg = { | |
1243 | .rpc_argp = &data->args, | |
1244 | .rpc_resp = &data->res, | |
1245 | .rpc_cred = first->wb_context->cred, | |
1246 | }; | |
1247 | struct rpc_task_setup task_setup_data = { | |
1248 | .task = &data->task, | |
1249 | .rpc_client = NFS_CLIENT(inode), | |
1250 | .rpc_message = &msg, | |
1251 | .callback_ops = &nfs_commit_ops, | |
1252 | .callback_data = data, | |
1253 | .workqueue = nfsiod_workqueue, | |
1254 | .flags = RPC_TASK_ASYNC, | |
1255 | .priority = priority, | |
1256 | }; | |
1257 | ||
1258 | /* Set up the RPC argument and reply structs | |
1259 | * NB: take care not to mess about with data->commit et al. */ | |
1260 | ||
1261 | list_splice_init(head, &data->pages); | |
1262 | ||
1263 | data->inode = inode; | |
1264 | data->cred = msg.rpc_cred; | |
1265 | ||
1266 | data->args.fh = NFS_FH(data->inode); | |
1267 | /* Note: we always request a commit of the entire inode */ | |
1268 | data->args.offset = 0; | |
1269 | data->args.count = 0; | |
1270 | data->args.context = get_nfs_open_context(first->wb_context); | |
1271 | data->res.count = 0; | |
1272 | data->res.fattr = &data->fattr; | |
1273 | data->res.verf = &data->verf; | |
1274 | nfs_fattr_init(&data->fattr); | |
1275 | ||
1276 | /* Set up the initial task struct. */ | |
1277 | NFS_PROTO(inode)->commit_setup(data, &msg); | |
1278 | ||
1279 | dprintk("NFS: %5u initiated commit call\n", data->task.tk_pid); | |
1280 | ||
1281 | task = rpc_run_task(&task_setup_data); | |
1282 | if (IS_ERR(task)) | |
1283 | return PTR_ERR(task); | |
1284 | rpc_put_task(task); | |
1285 | return 0; | |
1286 | } | |
1287 | ||
1288 | /* | |
1289 | * Commit dirty pages | |
1290 | */ | |
1291 | static int | |
1292 | nfs_commit_list(struct inode *inode, struct list_head *head, int how) | |
1293 | { | |
1294 | struct nfs_write_data *data; | |
1295 | struct nfs_page *req; | |
1296 | ||
1297 | data = nfs_commitdata_alloc(); | |
1298 | ||
1299 | if (!data) | |
1300 | goto out_bad; | |
1301 | ||
1302 | /* Set up the argument struct */ | |
1303 | return nfs_commit_rpcsetup(head, data, how); | |
1304 | out_bad: | |
1305 | while (!list_empty(head)) { | |
1306 | req = nfs_list_entry(head->next); | |
1307 | nfs_list_remove_request(req); | |
1308 | nfs_mark_request_commit(req); | |
1309 | dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS); | |
1310 | dec_bdi_stat(req->wb_page->mapping->backing_dev_info, | |
1311 | BDI_RECLAIMABLE); | |
1312 | nfs_clear_page_tag_locked(req); | |
1313 | } | |
1314 | nfs_commit_clear_lock(NFS_I(inode)); | |
1315 | return -ENOMEM; | |
1316 | } | |
1317 | ||
1318 | /* | |
1319 | * COMMIT call returned | |
1320 | */ | |
1321 | static void nfs_commit_done(struct rpc_task *task, void *calldata) | |
1322 | { | |
1323 | struct nfs_write_data *data = calldata; | |
1324 | ||
1325 | dprintk("NFS: %5u nfs_commit_done (status %d)\n", | |
1326 | task->tk_pid, task->tk_status); | |
1327 | ||
1328 | /* Call the NFS version-specific code */ | |
1329 | if (NFS_PROTO(data->inode)->commit_done(task, data) != 0) | |
1330 | return; | |
1331 | } | |
1332 | ||
1333 | static void nfs_commit_release(void *calldata) | |
1334 | { | |
1335 | struct nfs_write_data *data = calldata; | |
1336 | struct nfs_page *req; | |
1337 | int status = data->task.tk_status; | |
1338 | ||
1339 | while (!list_empty(&data->pages)) { | |
1340 | req = nfs_list_entry(data->pages.next); | |
1341 | nfs_list_remove_request(req); | |
1342 | nfs_clear_request_commit(req); | |
1343 | ||
1344 | dprintk("NFS: commit (%s/%lld %d@%lld)", | |
1345 | req->wb_context->path.dentry->d_inode->i_sb->s_id, | |
1346 | (long long)NFS_FILEID(req->wb_context->path.dentry->d_inode), | |
1347 | req->wb_bytes, | |
1348 | (long long)req_offset(req)); | |
1349 | if (status < 0) { | |
1350 | nfs_context_set_write_error(req->wb_context, status); | |
1351 | nfs_inode_remove_request(req); | |
1352 | dprintk(", error = %d\n", status); | |
1353 | goto next; | |
1354 | } | |
1355 | ||
1356 | /* Okay, COMMIT succeeded, apparently. Check the verifier | |
1357 | * returned by the server against all stored verfs. */ | |
1358 | if (!memcmp(req->wb_verf.verifier, data->verf.verifier, sizeof(data->verf.verifier))) { | |
1359 | /* We have a match */ | |
1360 | nfs_inode_remove_request(req); | |
1361 | dprintk(" OK\n"); | |
1362 | goto next; | |
1363 | } | |
1364 | /* We have a mismatch. Write the page again */ | |
1365 | dprintk(" mismatch\n"); | |
1366 | nfs_mark_request_dirty(req); | |
1367 | next: | |
1368 | nfs_clear_page_tag_locked(req); | |
1369 | } | |
1370 | nfs_commit_clear_lock(NFS_I(data->inode)); | |
1371 | nfs_commitdata_release(calldata); | |
1372 | } | |
1373 | ||
1374 | static const struct rpc_call_ops nfs_commit_ops = { | |
1375 | #if defined(CONFIG_NFS_V4_1) | |
1376 | .rpc_call_prepare = nfs_write_prepare, | |
1377 | #endif /* CONFIG_NFS_V4_1 */ | |
1378 | .rpc_call_done = nfs_commit_done, | |
1379 | .rpc_release = nfs_commit_release, | |
1380 | }; | |
1381 | ||
1382 | int nfs_commit_inode(struct inode *inode, int how) | |
1383 | { | |
1384 | LIST_HEAD(head); | |
1385 | int may_wait = how & FLUSH_SYNC; | |
1386 | int res = 0; | |
1387 | ||
1388 | if (!nfs_commit_set_lock(NFS_I(inode), may_wait)) | |
1389 | goto out_mark_dirty; | |
1390 | spin_lock(&inode->i_lock); | |
1391 | res = nfs_scan_commit(inode, &head, 0, 0); | |
1392 | spin_unlock(&inode->i_lock); | |
1393 | if (res) { | |
1394 | int error = nfs_commit_list(inode, &head, how); | |
1395 | if (error < 0) | |
1396 | return error; | |
1397 | if (may_wait) | |
1398 | wait_on_bit(&NFS_I(inode)->flags, NFS_INO_COMMIT, | |
1399 | nfs_wait_bit_killable, | |
1400 | TASK_KILLABLE); | |
1401 | else | |
1402 | goto out_mark_dirty; | |
1403 | } else | |
1404 | nfs_commit_clear_lock(NFS_I(inode)); | |
1405 | return res; | |
1406 | /* Note: If we exit without ensuring that the commit is complete, | |
1407 | * we must mark the inode as dirty. Otherwise, future calls to | |
1408 | * sync_inode() with the WB_SYNC_ALL flag set will fail to ensure | |
1409 | * that the data is on the disk. | |
1410 | */ | |
1411 | out_mark_dirty: | |
1412 | __mark_inode_dirty(inode, I_DIRTY_DATASYNC); | |
1413 | return res; | |
1414 | } | |
1415 | ||
1416 | static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc) | |
1417 | { | |
1418 | struct nfs_inode *nfsi = NFS_I(inode); | |
1419 | int flags = FLUSH_SYNC; | |
1420 | int ret = 0; | |
1421 | ||
1422 | /* Don't commit yet if this is a non-blocking flush and there are | |
1423 | * lots of outstanding writes for this mapping. | |
1424 | */ | |
1425 | if (wbc->sync_mode == WB_SYNC_NONE && | |
1426 | nfsi->ncommit <= (nfsi->npages >> 1)) | |
1427 | goto out_mark_dirty; | |
1428 | ||
1429 | if (wbc->nonblocking || wbc->for_background) | |
1430 | flags = 0; | |
1431 | ret = nfs_commit_inode(inode, flags); | |
1432 | if (ret >= 0) { | |
1433 | if (wbc->sync_mode == WB_SYNC_NONE) { | |
1434 | if (ret < wbc->nr_to_write) | |
1435 | wbc->nr_to_write -= ret; | |
1436 | else | |
1437 | wbc->nr_to_write = 0; | |
1438 | } | |
1439 | return 0; | |
1440 | } | |
1441 | out_mark_dirty: | |
1442 | __mark_inode_dirty(inode, I_DIRTY_DATASYNC); | |
1443 | return ret; | |
1444 | } | |
1445 | #else | |
1446 | int nfs_commit_inode(struct inode *inode, int how) | |
1447 | { | |
1448 | return 0; | |
1449 | } | |
1450 | ||
1451 | static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc) | |
1452 | { | |
1453 | return 0; | |
1454 | } | |
1455 | #endif | |
1456 | ||
1457 | int nfs_write_inode(struct inode *inode, struct writeback_control *wbc) | |
1458 | { | |
1459 | return nfs_commit_unstable_pages(inode, wbc); | |
1460 | } | |
1461 | ||
1462 | /* | |
1463 | * flush the inode to disk. | |
1464 | */ | |
1465 | int nfs_wb_all(struct inode *inode) | |
1466 | { | |
1467 | struct writeback_control wbc = { | |
1468 | .sync_mode = WB_SYNC_ALL, | |
1469 | .nr_to_write = LONG_MAX, | |
1470 | .range_start = 0, | |
1471 | .range_end = LLONG_MAX, | |
1472 | }; | |
1473 | ||
1474 | return sync_inode(inode, &wbc); | |
1475 | } | |
1476 | ||
1477 | int nfs_wb_page_cancel(struct inode *inode, struct page *page) | |
1478 | { | |
1479 | struct nfs_page *req; | |
1480 | int ret = 0; | |
1481 | ||
1482 | BUG_ON(!PageLocked(page)); | |
1483 | for (;;) { | |
1484 | wait_on_page_writeback(page); | |
1485 | req = nfs_page_find_request(page); | |
1486 | if (req == NULL) | |
1487 | break; | |
1488 | if (nfs_lock_request_dontget(req)) { | |
1489 | nfs_inode_remove_request(req); | |
1490 | /* | |
1491 | * In case nfs_inode_remove_request has marked the | |
1492 | * page as being dirty | |
1493 | */ | |
1494 | cancel_dirty_page(page, PAGE_CACHE_SIZE); | |
1495 | nfs_unlock_request(req); | |
1496 | break; | |
1497 | } | |
1498 | ret = nfs_wait_on_request(req); | |
1499 | nfs_release_request(req); | |
1500 | if (ret < 0) | |
1501 | break; | |
1502 | } | |
1503 | return ret; | |
1504 | } | |
1505 | ||
1506 | /* | |
1507 | * Write back all requests on one page - we do this before reading it. | |
1508 | */ | |
1509 | int nfs_wb_page(struct inode *inode, struct page *page) | |
1510 | { | |
1511 | loff_t range_start = page_offset(page); | |
1512 | loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1); | |
1513 | struct writeback_control wbc = { | |
1514 | .sync_mode = WB_SYNC_ALL, | |
1515 | .nr_to_write = 0, | |
1516 | .range_start = range_start, | |
1517 | .range_end = range_end, | |
1518 | }; | |
1519 | int ret; | |
1520 | ||
1521 | for (;;) { | |
1522 | wait_on_page_writeback(page); | |
1523 | if (clear_page_dirty_for_io(page)) { | |
1524 | ret = nfs_writepage_locked(page, &wbc); | |
1525 | if (ret < 0) | |
1526 | goto out_error; | |
1527 | continue; | |
1528 | } | |
1529 | if (!PagePrivate(page)) | |
1530 | break; | |
1531 | ret = nfs_commit_inode(inode, FLUSH_SYNC); | |
1532 | if (ret < 0) | |
1533 | goto out_error; | |
1534 | } | |
1535 | return 0; | |
1536 | out_error: | |
1537 | return ret; | |
1538 | } | |
1539 | ||
1540 | #ifdef CONFIG_MIGRATION | |
1541 | int nfs_migrate_page(struct address_space *mapping, struct page *newpage, | |
1542 | struct page *page) | |
1543 | { | |
1544 | struct nfs_page *req; | |
1545 | int ret; | |
1546 | ||
1547 | nfs_fscache_release_page(page, GFP_KERNEL); | |
1548 | ||
1549 | req = nfs_find_and_lock_request(page); | |
1550 | ret = PTR_ERR(req); | |
1551 | if (IS_ERR(req)) | |
1552 | goto out; | |
1553 | ||
1554 | ret = migrate_page(mapping, newpage, page); | |
1555 | if (!req) | |
1556 | goto out; | |
1557 | if (ret) | |
1558 | goto out_unlock; | |
1559 | page_cache_get(newpage); | |
1560 | spin_lock(&mapping->host->i_lock); | |
1561 | req->wb_page = newpage; | |
1562 | SetPagePrivate(newpage); | |
1563 | set_page_private(newpage, (unsigned long)req); | |
1564 | ClearPagePrivate(page); | |
1565 | set_page_private(page, 0); | |
1566 | spin_unlock(&mapping->host->i_lock); | |
1567 | page_cache_release(page); | |
1568 | out_unlock: | |
1569 | nfs_clear_page_tag_locked(req); | |
1570 | out: | |
1571 | return ret; | |
1572 | } | |
1573 | #endif | |
1574 | ||
1575 | int __init nfs_init_writepagecache(void) | |
1576 | { | |
1577 | nfs_wdata_cachep = kmem_cache_create("nfs_write_data", | |
1578 | sizeof(struct nfs_write_data), | |
1579 | 0, SLAB_HWCACHE_ALIGN, | |
1580 | NULL); | |
1581 | if (nfs_wdata_cachep == NULL) | |
1582 | return -ENOMEM; | |
1583 | ||
1584 | nfs_wdata_mempool = mempool_create_slab_pool(MIN_POOL_WRITE, | |
1585 | nfs_wdata_cachep); | |
1586 | if (nfs_wdata_mempool == NULL) | |
1587 | return -ENOMEM; | |
1588 | ||
1589 | nfs_commit_mempool = mempool_create_slab_pool(MIN_POOL_COMMIT, | |
1590 | nfs_wdata_cachep); | |
1591 | if (nfs_commit_mempool == NULL) | |
1592 | return -ENOMEM; | |
1593 | ||
1594 | /* | |
1595 | * NFS congestion size, scale with available memory. | |
1596 | * | |
1597 | * 64MB: 8192k | |
1598 | * 128MB: 11585k | |
1599 | * 256MB: 16384k | |
1600 | * 512MB: 23170k | |
1601 | * 1GB: 32768k | |
1602 | * 2GB: 46340k | |
1603 | * 4GB: 65536k | |
1604 | * 8GB: 92681k | |
1605 | * 16GB: 131072k | |
1606 | * | |
1607 | * This allows larger machines to have larger/more transfers. | |
1608 | * Limit the default to 256M | |
1609 | */ | |
1610 | nfs_congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10); | |
1611 | if (nfs_congestion_kb > 256*1024) | |
1612 | nfs_congestion_kb = 256*1024; | |
1613 | ||
1614 | return 0; | |
1615 | } | |
1616 | ||
1617 | void nfs_destroy_writepagecache(void) | |
1618 | { | |
1619 | mempool_destroy(nfs_commit_mempool); | |
1620 | mempool_destroy(nfs_wdata_mempool); | |
1621 | kmem_cache_destroy(nfs_wdata_cachep); | |
1622 | } | |
1623 |