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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 | ||
17 | #include <linux/sunrpc/clnt.h> | |
18 | #include <linux/nfs_fs.h> | |
19 | #include <linux/nfs_mount.h> | |
20 | #include <linux/nfs_page.h> | |
21 | #include <linux/backing-dev.h> | |
22 | ||
23 | #include <asm/uaccess.h> | |
24 | ||
25 | #include "delegation.h" | |
26 | #include "internal.h" | |
27 | #include "iostat.h" | |
28 | ||
29 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE | |
30 | ||
31 | #define MIN_POOL_WRITE (32) | |
32 | #define MIN_POOL_COMMIT (4) | |
33 | ||
34 | /* | |
35 | * Local function declarations | |
36 | */ | |
37 | static struct nfs_page * nfs_update_request(struct nfs_open_context*, | |
38 | struct page *, | |
39 | unsigned int, unsigned int); | |
40 | static void nfs_pageio_init_write(struct nfs_pageio_descriptor *desc, | |
41 | struct inode *inode, int ioflags); | |
42 | static const struct rpc_call_ops nfs_write_partial_ops; | |
43 | static const struct rpc_call_ops nfs_write_full_ops; | |
44 | static const struct rpc_call_ops nfs_commit_ops; | |
45 | ||
46 | static struct kmem_cache *nfs_wdata_cachep; | |
47 | static mempool_t *nfs_wdata_mempool; | |
48 | static mempool_t *nfs_commit_mempool; | |
49 | ||
50 | struct nfs_write_data *nfs_commit_alloc(void) | |
51 | { | |
52 | struct nfs_write_data *p = mempool_alloc(nfs_commit_mempool, GFP_NOFS); | |
53 | ||
54 | if (p) { | |
55 | memset(p, 0, sizeof(*p)); | |
56 | INIT_LIST_HEAD(&p->pages); | |
57 | } | |
58 | return p; | |
59 | } | |
60 | ||
61 | static void nfs_commit_rcu_free(struct rcu_head *head) | |
62 | { | |
63 | struct nfs_write_data *p = container_of(head, struct nfs_write_data, task.u.tk_rcu); | |
64 | if (p && (p->pagevec != &p->page_array[0])) | |
65 | kfree(p->pagevec); | |
66 | mempool_free(p, nfs_commit_mempool); | |
67 | } | |
68 | ||
69 | void nfs_commit_free(struct nfs_write_data *wdata) | |
70 | { | |
71 | call_rcu_bh(&wdata->task.u.tk_rcu, nfs_commit_rcu_free); | |
72 | } | |
73 | ||
74 | struct nfs_write_data *nfs_writedata_alloc(unsigned int pagecount) | |
75 | { | |
76 | struct nfs_write_data *p = mempool_alloc(nfs_wdata_mempool, GFP_NOFS); | |
77 | ||
78 | if (p) { | |
79 | memset(p, 0, sizeof(*p)); | |
80 | INIT_LIST_HEAD(&p->pages); | |
81 | p->npages = pagecount; | |
82 | if (pagecount <= ARRAY_SIZE(p->page_array)) | |
83 | p->pagevec = p->page_array; | |
84 | else { | |
85 | p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_NOFS); | |
86 | if (!p->pagevec) { | |
87 | mempool_free(p, nfs_wdata_mempool); | |
88 | p = NULL; | |
89 | } | |
90 | } | |
91 | } | |
92 | return p; | |
93 | } | |
94 | ||
95 | static void nfs_writedata_rcu_free(struct rcu_head *head) | |
96 | { | |
97 | struct nfs_write_data *p = container_of(head, struct nfs_write_data, task.u.tk_rcu); | |
98 | if (p && (p->pagevec != &p->page_array[0])) | |
99 | kfree(p->pagevec); | |
100 | mempool_free(p, nfs_wdata_mempool); | |
101 | } | |
102 | ||
103 | static void nfs_writedata_free(struct nfs_write_data *wdata) | |
104 | { | |
105 | call_rcu_bh(&wdata->task.u.tk_rcu, nfs_writedata_rcu_free); | |
106 | } | |
107 | ||
108 | void nfs_writedata_release(void *wdata) | |
109 | { | |
110 | nfs_writedata_free(wdata); | |
111 | } | |
112 | ||
113 | static struct nfs_page *nfs_page_find_request_locked(struct page *page) | |
114 | { | |
115 | struct nfs_page *req = NULL; | |
116 | ||
117 | if (PagePrivate(page)) { | |
118 | req = (struct nfs_page *)page_private(page); | |
119 | if (req != NULL) | |
120 | kref_get(&req->wb_kref); | |
121 | } | |
122 | return req; | |
123 | } | |
124 | ||
125 | static struct nfs_page *nfs_page_find_request(struct page *page) | |
126 | { | |
127 | struct nfs_page *req = NULL; | |
128 | spinlock_t *req_lock = &NFS_I(page->mapping->host)->req_lock; | |
129 | ||
130 | spin_lock(req_lock); | |
131 | req = nfs_page_find_request_locked(page); | |
132 | spin_unlock(req_lock); | |
133 | return req; | |
134 | } | |
135 | ||
136 | /* Adjust the file length if we're writing beyond the end */ | |
137 | static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count) | |
138 | { | |
139 | struct inode *inode = page->mapping->host; | |
140 | loff_t end, i_size = i_size_read(inode); | |
141 | pgoff_t end_index = (i_size - 1) >> PAGE_CACHE_SHIFT; | |
142 | ||
143 | if (i_size > 0 && page->index < end_index) | |
144 | return; | |
145 | end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + ((loff_t)offset+count); | |
146 | if (i_size >= end) | |
147 | return; | |
148 | nfs_inc_stats(inode, NFSIOS_EXTENDWRITE); | |
149 | i_size_write(inode, end); | |
150 | } | |
151 | ||
152 | /* A writeback failed: mark the page as bad, and invalidate the page cache */ | |
153 | static void nfs_set_pageerror(struct page *page) | |
154 | { | |
155 | SetPageError(page); | |
156 | nfs_zap_mapping(page->mapping->host, page->mapping); | |
157 | } | |
158 | ||
159 | /* We can set the PG_uptodate flag if we see that a write request | |
160 | * covers the full page. | |
161 | */ | |
162 | static void nfs_mark_uptodate(struct page *page, unsigned int base, unsigned int count) | |
163 | { | |
164 | if (PageUptodate(page)) | |
165 | return; | |
166 | if (base != 0) | |
167 | return; | |
168 | if (count != nfs_page_length(page)) | |
169 | return; | |
170 | if (count != PAGE_CACHE_SIZE) | |
171 | zero_user_page(page, count, PAGE_CACHE_SIZE - count, KM_USER0); | |
172 | SetPageUptodate(page); | |
173 | } | |
174 | ||
175 | static int nfs_writepage_setup(struct nfs_open_context *ctx, struct page *page, | |
176 | unsigned int offset, unsigned int count) | |
177 | { | |
178 | struct nfs_page *req; | |
179 | int ret; | |
180 | ||
181 | for (;;) { | |
182 | req = nfs_update_request(ctx, page, offset, count); | |
183 | if (!IS_ERR(req)) | |
184 | break; | |
185 | ret = PTR_ERR(req); | |
186 | if (ret != -EBUSY) | |
187 | return ret; | |
188 | ret = nfs_wb_page(page->mapping->host, page); | |
189 | if (ret != 0) | |
190 | return ret; | |
191 | } | |
192 | /* Update file length */ | |
193 | nfs_grow_file(page, offset, count); | |
194 | nfs_unlock_request(req); | |
195 | return 0; | |
196 | } | |
197 | ||
198 | static int wb_priority(struct writeback_control *wbc) | |
199 | { | |
200 | if (wbc->for_reclaim) | |
201 | return FLUSH_HIGHPRI | FLUSH_STABLE; | |
202 | if (wbc->for_kupdate) | |
203 | return FLUSH_LOWPRI; | |
204 | return 0; | |
205 | } | |
206 | ||
207 | /* | |
208 | * NFS congestion control | |
209 | */ | |
210 | ||
211 | int nfs_congestion_kb; | |
212 | ||
213 | #define NFS_CONGESTION_ON_THRESH (nfs_congestion_kb >> (PAGE_SHIFT-10)) | |
214 | #define NFS_CONGESTION_OFF_THRESH \ | |
215 | (NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2)) | |
216 | ||
217 | static int nfs_set_page_writeback(struct page *page) | |
218 | { | |
219 | int ret = test_set_page_writeback(page); | |
220 | ||
221 | if (!ret) { | |
222 | struct inode *inode = page->mapping->host; | |
223 | struct nfs_server *nfss = NFS_SERVER(inode); | |
224 | ||
225 | if (atomic_long_inc_return(&nfss->writeback) > | |
226 | NFS_CONGESTION_ON_THRESH) | |
227 | set_bdi_congested(&nfss->backing_dev_info, WRITE); | |
228 | } | |
229 | return ret; | |
230 | } | |
231 | ||
232 | static void nfs_end_page_writeback(struct page *page) | |
233 | { | |
234 | struct inode *inode = page->mapping->host; | |
235 | struct nfs_server *nfss = NFS_SERVER(inode); | |
236 | ||
237 | end_page_writeback(page); | |
238 | if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) { | |
239 | clear_bdi_congested(&nfss->backing_dev_info, WRITE); | |
240 | congestion_end(WRITE); | |
241 | } | |
242 | } | |
243 | ||
244 | /* | |
245 | * Find an associated nfs write request, and prepare to flush it out | |
246 | * Returns 1 if there was no write request, or if the request was | |
247 | * already tagged by nfs_set_page_dirty.Returns 0 if the request | |
248 | * was not tagged. | |
249 | * May also return an error if the user signalled nfs_wait_on_request(). | |
250 | */ | |
251 | static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio, | |
252 | struct page *page) | |
253 | { | |
254 | struct nfs_page *req; | |
255 | struct nfs_inode *nfsi = NFS_I(page->mapping->host); | |
256 | spinlock_t *req_lock = &nfsi->req_lock; | |
257 | int ret; | |
258 | ||
259 | spin_lock(req_lock); | |
260 | for(;;) { | |
261 | req = nfs_page_find_request_locked(page); | |
262 | if (req == NULL) { | |
263 | spin_unlock(req_lock); | |
264 | return 1; | |
265 | } | |
266 | if (nfs_lock_request_dontget(req)) | |
267 | break; | |
268 | /* Note: If we hold the page lock, as is the case in nfs_writepage, | |
269 | * then the call to nfs_lock_request_dontget() will always | |
270 | * succeed provided that someone hasn't already marked the | |
271 | * request as dirty (in which case we don't care). | |
272 | */ | |
273 | spin_unlock(req_lock); | |
274 | ret = nfs_wait_on_request(req); | |
275 | nfs_release_request(req); | |
276 | if (ret != 0) | |
277 | return ret; | |
278 | spin_lock(req_lock); | |
279 | } | |
280 | if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) { | |
281 | /* This request is marked for commit */ | |
282 | spin_unlock(req_lock); | |
283 | nfs_unlock_request(req); | |
284 | nfs_pageio_complete(pgio); | |
285 | return 1; | |
286 | } | |
287 | if (nfs_set_page_writeback(page) != 0) { | |
288 | spin_unlock(req_lock); | |
289 | BUG(); | |
290 | } | |
291 | radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, | |
292 | NFS_PAGE_TAG_LOCKED); | |
293 | ret = test_bit(PG_NEED_FLUSH, &req->wb_flags); | |
294 | spin_unlock(req_lock); | |
295 | nfs_pageio_add_request(pgio, req); | |
296 | return ret; | |
297 | } | |
298 | ||
299 | /* | |
300 | * Write an mmapped page to the server. | |
301 | */ | |
302 | static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc) | |
303 | { | |
304 | struct nfs_pageio_descriptor mypgio, *pgio; | |
305 | struct nfs_open_context *ctx; | |
306 | struct inode *inode = page->mapping->host; | |
307 | unsigned offset; | |
308 | int err; | |
309 | ||
310 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); | |
311 | nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1); | |
312 | ||
313 | if (wbc->for_writepages) | |
314 | pgio = wbc->fs_private; | |
315 | else { | |
316 | nfs_pageio_init_write(&mypgio, inode, wb_priority(wbc)); | |
317 | pgio = &mypgio; | |
318 | } | |
319 | ||
320 | nfs_pageio_cond_complete(pgio, page->index); | |
321 | ||
322 | err = nfs_page_async_flush(pgio, page); | |
323 | if (err <= 0) | |
324 | goto out; | |
325 | err = 0; | |
326 | offset = nfs_page_length(page); | |
327 | if (!offset) | |
328 | goto out; | |
329 | ||
330 | nfs_pageio_cond_complete(pgio, page->index); | |
331 | ||
332 | ctx = nfs_find_open_context(inode, NULL, FMODE_WRITE); | |
333 | if (ctx == NULL) { | |
334 | err = -EBADF; | |
335 | goto out; | |
336 | } | |
337 | err = nfs_writepage_setup(ctx, page, 0, offset); | |
338 | put_nfs_open_context(ctx); | |
339 | if (err != 0) | |
340 | goto out; | |
341 | err = nfs_page_async_flush(pgio, page); | |
342 | if (err > 0) | |
343 | err = 0; | |
344 | out: | |
345 | if (!wbc->for_writepages) | |
346 | nfs_pageio_complete(pgio); | |
347 | return err; | |
348 | } | |
349 | ||
350 | int nfs_writepage(struct page *page, struct writeback_control *wbc) | |
351 | { | |
352 | int err; | |
353 | ||
354 | err = nfs_writepage_locked(page, wbc); | |
355 | unlock_page(page); | |
356 | return err; | |
357 | } | |
358 | ||
359 | int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) | |
360 | { | |
361 | struct inode *inode = mapping->host; | |
362 | struct nfs_pageio_descriptor pgio; | |
363 | int err; | |
364 | ||
365 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); | |
366 | ||
367 | nfs_pageio_init_write(&pgio, inode, wb_priority(wbc)); | |
368 | wbc->fs_private = &pgio; | |
369 | err = generic_writepages(mapping, wbc); | |
370 | nfs_pageio_complete(&pgio); | |
371 | if (err) | |
372 | return err; | |
373 | if (pgio.pg_error) | |
374 | return pgio.pg_error; | |
375 | return 0; | |
376 | } | |
377 | ||
378 | /* | |
379 | * Insert a write request into an inode | |
380 | */ | |
381 | static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req) | |
382 | { | |
383 | struct nfs_inode *nfsi = NFS_I(inode); | |
384 | int error; | |
385 | ||
386 | error = radix_tree_insert(&nfsi->nfs_page_tree, req->wb_index, req); | |
387 | BUG_ON(error == -EEXIST); | |
388 | if (error) | |
389 | return error; | |
390 | if (!nfsi->npages) { | |
391 | igrab(inode); | |
392 | nfs_begin_data_update(inode); | |
393 | if (nfs_have_delegation(inode, FMODE_WRITE)) | |
394 | nfsi->change_attr++; | |
395 | } | |
396 | SetPagePrivate(req->wb_page); | |
397 | set_page_private(req->wb_page, (unsigned long)req); | |
398 | if (PageDirty(req->wb_page)) | |
399 | set_bit(PG_NEED_FLUSH, &req->wb_flags); | |
400 | nfsi->npages++; | |
401 | kref_get(&req->wb_kref); | |
402 | return 0; | |
403 | } | |
404 | ||
405 | /* | |
406 | * Remove a write request from an inode | |
407 | */ | |
408 | static void nfs_inode_remove_request(struct nfs_page *req) | |
409 | { | |
410 | struct inode *inode = req->wb_context->path.dentry->d_inode; | |
411 | struct nfs_inode *nfsi = NFS_I(inode); | |
412 | ||
413 | BUG_ON (!NFS_WBACK_BUSY(req)); | |
414 | ||
415 | spin_lock(&nfsi->req_lock); | |
416 | set_page_private(req->wb_page, 0); | |
417 | ClearPagePrivate(req->wb_page); | |
418 | radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index); | |
419 | if (test_and_clear_bit(PG_NEED_FLUSH, &req->wb_flags)) | |
420 | __set_page_dirty_nobuffers(req->wb_page); | |
421 | nfsi->npages--; | |
422 | if (!nfsi->npages) { | |
423 | spin_unlock(&nfsi->req_lock); | |
424 | nfs_end_data_update(inode); | |
425 | iput(inode); | |
426 | } else | |
427 | spin_unlock(&nfsi->req_lock); | |
428 | nfs_clear_request(req); | |
429 | nfs_release_request(req); | |
430 | } | |
431 | ||
432 | static void | |
433 | nfs_redirty_request(struct nfs_page *req) | |
434 | { | |
435 | __set_page_dirty_nobuffers(req->wb_page); | |
436 | } | |
437 | ||
438 | /* | |
439 | * Check if a request is dirty | |
440 | */ | |
441 | static inline int | |
442 | nfs_dirty_request(struct nfs_page *req) | |
443 | { | |
444 | struct page *page = req->wb_page; | |
445 | ||
446 | if (page == NULL || test_bit(PG_NEED_COMMIT, &req->wb_flags)) | |
447 | return 0; | |
448 | return !PageWriteback(req->wb_page); | |
449 | } | |
450 | ||
451 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
452 | /* | |
453 | * Add a request to the inode's commit list. | |
454 | */ | |
455 | static void | |
456 | nfs_mark_request_commit(struct nfs_page *req) | |
457 | { | |
458 | struct inode *inode = req->wb_context->path.dentry->d_inode; | |
459 | struct nfs_inode *nfsi = NFS_I(inode); | |
460 | ||
461 | spin_lock(&nfsi->req_lock); | |
462 | nfsi->ncommit++; | |
463 | set_bit(PG_NEED_COMMIT, &(req)->wb_flags); | |
464 | radix_tree_tag_set(&nfsi->nfs_page_tree, | |
465 | req->wb_index, | |
466 | NFS_PAGE_TAG_COMMIT); | |
467 | spin_unlock(&nfsi->req_lock); | |
468 | inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS); | |
469 | __mark_inode_dirty(inode, I_DIRTY_DATASYNC); | |
470 | } | |
471 | ||
472 | static inline | |
473 | int nfs_write_need_commit(struct nfs_write_data *data) | |
474 | { | |
475 | return data->verf.committed != NFS_FILE_SYNC; | |
476 | } | |
477 | ||
478 | static inline | |
479 | int nfs_reschedule_unstable_write(struct nfs_page *req) | |
480 | { | |
481 | if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) { | |
482 | nfs_mark_request_commit(req); | |
483 | return 1; | |
484 | } | |
485 | if (test_and_clear_bit(PG_NEED_RESCHED, &req->wb_flags)) { | |
486 | nfs_redirty_request(req); | |
487 | return 1; | |
488 | } | |
489 | return 0; | |
490 | } | |
491 | #else | |
492 | static inline void | |
493 | nfs_mark_request_commit(struct nfs_page *req) | |
494 | { | |
495 | } | |
496 | ||
497 | static inline | |
498 | int nfs_write_need_commit(struct nfs_write_data *data) | |
499 | { | |
500 | return 0; | |
501 | } | |
502 | ||
503 | static inline | |
504 | int nfs_reschedule_unstable_write(struct nfs_page *req) | |
505 | { | |
506 | return 0; | |
507 | } | |
508 | #endif | |
509 | ||
510 | /* | |
511 | * Wait for a request to complete. | |
512 | * | |
513 | * Interruptible by signals only if mounted with intr flag. | |
514 | */ | |
515 | static int nfs_wait_on_requests_locked(struct inode *inode, pgoff_t idx_start, unsigned int npages) | |
516 | { | |
517 | struct nfs_inode *nfsi = NFS_I(inode); | |
518 | struct nfs_page *req; | |
519 | pgoff_t idx_end, next; | |
520 | unsigned int res = 0; | |
521 | int error; | |
522 | ||
523 | if (npages == 0) | |
524 | idx_end = ~0; | |
525 | else | |
526 | idx_end = idx_start + npages - 1; | |
527 | ||
528 | next = idx_start; | |
529 | while (radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree, (void **)&req, next, 1, NFS_PAGE_TAG_LOCKED)) { | |
530 | if (req->wb_index > idx_end) | |
531 | break; | |
532 | ||
533 | next = req->wb_index + 1; | |
534 | BUG_ON(!NFS_WBACK_BUSY(req)); | |
535 | ||
536 | kref_get(&req->wb_kref); | |
537 | spin_unlock(&nfsi->req_lock); | |
538 | error = nfs_wait_on_request(req); | |
539 | nfs_release_request(req); | |
540 | spin_lock(&nfsi->req_lock); | |
541 | if (error < 0) | |
542 | return error; | |
543 | res++; | |
544 | } | |
545 | return res; | |
546 | } | |
547 | ||
548 | static void nfs_cancel_commit_list(struct list_head *head) | |
549 | { | |
550 | struct nfs_page *req; | |
551 | ||
552 | while(!list_empty(head)) { | |
553 | req = nfs_list_entry(head->next); | |
554 | dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS); | |
555 | nfs_list_remove_request(req); | |
556 | clear_bit(PG_NEED_COMMIT, &(req)->wb_flags); | |
557 | nfs_inode_remove_request(req); | |
558 | nfs_unlock_request(req); | |
559 | } | |
560 | } | |
561 | ||
562 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
563 | /* | |
564 | * nfs_scan_commit - Scan an inode for commit requests | |
565 | * @inode: NFS inode to scan | |
566 | * @dst: destination list | |
567 | * @idx_start: lower bound of page->index to scan. | |
568 | * @npages: idx_start + npages sets the upper bound to scan. | |
569 | * | |
570 | * Moves requests from the inode's 'commit' request list. | |
571 | * The requests are *not* checked to ensure that they form a contiguous set. | |
572 | */ | |
573 | static int | |
574 | nfs_scan_commit(struct inode *inode, struct list_head *dst, pgoff_t idx_start, unsigned int npages) | |
575 | { | |
576 | struct nfs_inode *nfsi = NFS_I(inode); | |
577 | int res = 0; | |
578 | ||
579 | if (nfsi->ncommit != 0) { | |
580 | res = nfs_scan_list(nfsi, dst, idx_start, npages, | |
581 | NFS_PAGE_TAG_COMMIT); | |
582 | nfsi->ncommit -= res; | |
583 | } | |
584 | return res; | |
585 | } | |
586 | #else | |
587 | static inline int nfs_scan_commit(struct inode *inode, struct list_head *dst, pgoff_t idx_start, unsigned int npages) | |
588 | { | |
589 | return 0; | |
590 | } | |
591 | #endif | |
592 | ||
593 | /* | |
594 | * Try to update any existing write request, or create one if there is none. | |
595 | * In order to match, the request's credentials must match those of | |
596 | * the calling process. | |
597 | * | |
598 | * Note: Should always be called with the Page Lock held! | |
599 | */ | |
600 | static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx, | |
601 | struct page *page, unsigned int offset, unsigned int bytes) | |
602 | { | |
603 | struct address_space *mapping = page->mapping; | |
604 | struct inode *inode = mapping->host; | |
605 | struct nfs_inode *nfsi = NFS_I(inode); | |
606 | struct nfs_page *req, *new = NULL; | |
607 | pgoff_t rqend, end; | |
608 | ||
609 | end = offset + bytes; | |
610 | ||
611 | for (;;) { | |
612 | /* Loop over all inode entries and see if we find | |
613 | * A request for the page we wish to update | |
614 | */ | |
615 | spin_lock(&nfsi->req_lock); | |
616 | req = nfs_page_find_request_locked(page); | |
617 | if (req) { | |
618 | if (!nfs_lock_request_dontget(req)) { | |
619 | int error; | |
620 | ||
621 | spin_unlock(&nfsi->req_lock); | |
622 | error = nfs_wait_on_request(req); | |
623 | nfs_release_request(req); | |
624 | if (error < 0) { | |
625 | if (new) | |
626 | nfs_release_request(new); | |
627 | return ERR_PTR(error); | |
628 | } | |
629 | continue; | |
630 | } | |
631 | spin_unlock(&nfsi->req_lock); | |
632 | if (new) | |
633 | nfs_release_request(new); | |
634 | break; | |
635 | } | |
636 | ||
637 | if (new) { | |
638 | int error; | |
639 | nfs_lock_request_dontget(new); | |
640 | error = nfs_inode_add_request(inode, new); | |
641 | if (error) { | |
642 | spin_unlock(&nfsi->req_lock); | |
643 | nfs_unlock_request(new); | |
644 | return ERR_PTR(error); | |
645 | } | |
646 | spin_unlock(&nfsi->req_lock); | |
647 | return new; | |
648 | } | |
649 | spin_unlock(&nfsi->req_lock); | |
650 | ||
651 | new = nfs_create_request(ctx, inode, page, offset, bytes); | |
652 | if (IS_ERR(new)) | |
653 | return new; | |
654 | } | |
655 | ||
656 | /* We have a request for our page. | |
657 | * If the creds don't match, or the | |
658 | * page addresses don't match, | |
659 | * tell the caller to wait on the conflicting | |
660 | * request. | |
661 | */ | |
662 | rqend = req->wb_offset + req->wb_bytes; | |
663 | if (req->wb_context != ctx | |
664 | || req->wb_page != page | |
665 | || !nfs_dirty_request(req) | |
666 | || offset > rqend || end < req->wb_offset) { | |
667 | nfs_unlock_request(req); | |
668 | return ERR_PTR(-EBUSY); | |
669 | } | |
670 | ||
671 | /* Okay, the request matches. Update the region */ | |
672 | if (offset < req->wb_offset) { | |
673 | req->wb_offset = offset; | |
674 | req->wb_pgbase = offset; | |
675 | req->wb_bytes = rqend - req->wb_offset; | |
676 | } | |
677 | ||
678 | if (end > rqend) | |
679 | req->wb_bytes = end - req->wb_offset; | |
680 | ||
681 | return req; | |
682 | } | |
683 | ||
684 | int nfs_flush_incompatible(struct file *file, struct page *page) | |
685 | { | |
686 | struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data; | |
687 | struct nfs_page *req; | |
688 | int do_flush, status; | |
689 | /* | |
690 | * Look for a request corresponding to this page. If there | |
691 | * is one, and it belongs to another file, we flush it out | |
692 | * before we try to copy anything into the page. Do this | |
693 | * due to the lack of an ACCESS-type call in NFSv2. | |
694 | * Also do the same if we find a request from an existing | |
695 | * dropped page. | |
696 | */ | |
697 | do { | |
698 | req = nfs_page_find_request(page); | |
699 | if (req == NULL) | |
700 | return 0; | |
701 | do_flush = req->wb_page != page || req->wb_context != ctx | |
702 | || !nfs_dirty_request(req); | |
703 | nfs_release_request(req); | |
704 | if (!do_flush) | |
705 | return 0; | |
706 | status = nfs_wb_page(page->mapping->host, page); | |
707 | } while (status == 0); | |
708 | return status; | |
709 | } | |
710 | ||
711 | /* | |
712 | * Update and possibly write a cached page of an NFS file. | |
713 | * | |
714 | * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad | |
715 | * things with a page scheduled for an RPC call (e.g. invalidate it). | |
716 | */ | |
717 | int nfs_updatepage(struct file *file, struct page *page, | |
718 | unsigned int offset, unsigned int count) | |
719 | { | |
720 | struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data; | |
721 | struct inode *inode = page->mapping->host; | |
722 | int status = 0; | |
723 | ||
724 | nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE); | |
725 | ||
726 | dprintk("NFS: nfs_updatepage(%s/%s %d@%Ld)\n", | |
727 | file->f_path.dentry->d_parent->d_name.name, | |
728 | file->f_path.dentry->d_name.name, count, | |
729 | (long long)(page_offset(page) +offset)); | |
730 | ||
731 | /* If we're not using byte range locks, and we know the page | |
732 | * is entirely in cache, it may be more efficient to avoid | |
733 | * fragmenting write requests. | |
734 | */ | |
735 | if (PageUptodate(page) && inode->i_flock == NULL && !(file->f_mode & O_SYNC)) { | |
736 | count = max(count + offset, nfs_page_length(page)); | |
737 | offset = 0; | |
738 | } | |
739 | ||
740 | status = nfs_writepage_setup(ctx, page, offset, count); | |
741 | __set_page_dirty_nobuffers(page); | |
742 | ||
743 | dprintk("NFS: nfs_updatepage returns %d (isize %Ld)\n", | |
744 | status, (long long)i_size_read(inode)); | |
745 | if (status < 0) | |
746 | nfs_set_pageerror(page); | |
747 | return status; | |
748 | } | |
749 | ||
750 | static void nfs_writepage_release(struct nfs_page *req) | |
751 | { | |
752 | ||
753 | if (PageError(req->wb_page)) { | |
754 | nfs_end_page_writeback(req->wb_page); | |
755 | nfs_inode_remove_request(req); | |
756 | } else if (!nfs_reschedule_unstable_write(req)) { | |
757 | /* Set the PG_uptodate flag */ | |
758 | nfs_mark_uptodate(req->wb_page, req->wb_pgbase, req->wb_bytes); | |
759 | nfs_end_page_writeback(req->wb_page); | |
760 | nfs_inode_remove_request(req); | |
761 | } else | |
762 | nfs_end_page_writeback(req->wb_page); | |
763 | nfs_clear_page_tag_locked(req); | |
764 | } | |
765 | ||
766 | static inline int flush_task_priority(int how) | |
767 | { | |
768 | switch (how & (FLUSH_HIGHPRI|FLUSH_LOWPRI)) { | |
769 | case FLUSH_HIGHPRI: | |
770 | return RPC_PRIORITY_HIGH; | |
771 | case FLUSH_LOWPRI: | |
772 | return RPC_PRIORITY_LOW; | |
773 | } | |
774 | return RPC_PRIORITY_NORMAL; | |
775 | } | |
776 | ||
777 | /* | |
778 | * Set up the argument/result storage required for the RPC call. | |
779 | */ | |
780 | static void nfs_write_rpcsetup(struct nfs_page *req, | |
781 | struct nfs_write_data *data, | |
782 | const struct rpc_call_ops *call_ops, | |
783 | unsigned int count, unsigned int offset, | |
784 | int how) | |
785 | { | |
786 | struct inode *inode; | |
787 | int flags; | |
788 | ||
789 | /* Set up the RPC argument and reply structs | |
790 | * NB: take care not to mess about with data->commit et al. */ | |
791 | ||
792 | data->req = req; | |
793 | data->inode = inode = req->wb_context->path.dentry->d_inode; | |
794 | data->cred = req->wb_context->cred; | |
795 | ||
796 | data->args.fh = NFS_FH(inode); | |
797 | data->args.offset = req_offset(req) + offset; | |
798 | data->args.pgbase = req->wb_pgbase + offset; | |
799 | data->args.pages = data->pagevec; | |
800 | data->args.count = count; | |
801 | data->args.context = req->wb_context; | |
802 | ||
803 | data->res.fattr = &data->fattr; | |
804 | data->res.count = count; | |
805 | data->res.verf = &data->verf; | |
806 | nfs_fattr_init(&data->fattr); | |
807 | ||
808 | /* Set up the initial task struct. */ | |
809 | flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC; | |
810 | rpc_init_task(&data->task, NFS_CLIENT(inode), flags, call_ops, data); | |
811 | NFS_PROTO(inode)->write_setup(data, how); | |
812 | ||
813 | data->task.tk_priority = flush_task_priority(how); | |
814 | data->task.tk_cookie = (unsigned long)inode; | |
815 | ||
816 | dprintk("NFS: %5u initiated write call " | |
817 | "(req %s/%Ld, %u bytes @ offset %Lu)\n", | |
818 | data->task.tk_pid, | |
819 | inode->i_sb->s_id, | |
820 | (long long)NFS_FILEID(inode), | |
821 | count, | |
822 | (unsigned long long)data->args.offset); | |
823 | } | |
824 | ||
825 | static void nfs_execute_write(struct nfs_write_data *data) | |
826 | { | |
827 | struct rpc_clnt *clnt = NFS_CLIENT(data->inode); | |
828 | sigset_t oldset; | |
829 | ||
830 | rpc_clnt_sigmask(clnt, &oldset); | |
831 | rpc_execute(&data->task); | |
832 | rpc_clnt_sigunmask(clnt, &oldset); | |
833 | } | |
834 | ||
835 | /* | |
836 | * Generate multiple small requests to write out a single | |
837 | * contiguous dirty area on one page. | |
838 | */ | |
839 | static int nfs_flush_multi(struct inode *inode, struct list_head *head, unsigned int npages, size_t count, int how) | |
840 | { | |
841 | struct nfs_page *req = nfs_list_entry(head->next); | |
842 | struct page *page = req->wb_page; | |
843 | struct nfs_write_data *data; | |
844 | size_t wsize = NFS_SERVER(inode)->wsize, nbytes; | |
845 | unsigned int offset; | |
846 | int requests = 0; | |
847 | LIST_HEAD(list); | |
848 | ||
849 | nfs_list_remove_request(req); | |
850 | ||
851 | nbytes = count; | |
852 | do { | |
853 | size_t len = min(nbytes, wsize); | |
854 | ||
855 | data = nfs_writedata_alloc(1); | |
856 | if (!data) | |
857 | goto out_bad; | |
858 | list_add(&data->pages, &list); | |
859 | requests++; | |
860 | nbytes -= len; | |
861 | } while (nbytes != 0); | |
862 | atomic_set(&req->wb_complete, requests); | |
863 | ||
864 | ClearPageError(page); | |
865 | offset = 0; | |
866 | nbytes = count; | |
867 | do { | |
868 | data = list_entry(list.next, struct nfs_write_data, pages); | |
869 | list_del_init(&data->pages); | |
870 | ||
871 | data->pagevec[0] = page; | |
872 | ||
873 | if (nbytes < wsize) | |
874 | wsize = nbytes; | |
875 | nfs_write_rpcsetup(req, data, &nfs_write_partial_ops, | |
876 | wsize, offset, how); | |
877 | offset += wsize; | |
878 | nbytes -= wsize; | |
879 | nfs_execute_write(data); | |
880 | } while (nbytes != 0); | |
881 | ||
882 | return 0; | |
883 | ||
884 | out_bad: | |
885 | while (!list_empty(&list)) { | |
886 | data = list_entry(list.next, struct nfs_write_data, pages); | |
887 | list_del(&data->pages); | |
888 | nfs_writedata_release(data); | |
889 | } | |
890 | nfs_redirty_request(req); | |
891 | nfs_end_page_writeback(req->wb_page); | |
892 | nfs_clear_page_tag_locked(req); | |
893 | return -ENOMEM; | |
894 | } | |
895 | ||
896 | /* | |
897 | * Create an RPC task for the given write request and kick it. | |
898 | * The page must have been locked by the caller. | |
899 | * | |
900 | * It may happen that the page we're passed is not marked dirty. | |
901 | * This is the case if nfs_updatepage detects a conflicting request | |
902 | * that has been written but not committed. | |
903 | */ | |
904 | static int nfs_flush_one(struct inode *inode, struct list_head *head, unsigned int npages, size_t count, int how) | |
905 | { | |
906 | struct nfs_page *req; | |
907 | struct page **pages; | |
908 | struct nfs_write_data *data; | |
909 | ||
910 | data = nfs_writedata_alloc(npages); | |
911 | if (!data) | |
912 | goto out_bad; | |
913 | ||
914 | pages = data->pagevec; | |
915 | while (!list_empty(head)) { | |
916 | req = nfs_list_entry(head->next); | |
917 | nfs_list_remove_request(req); | |
918 | nfs_list_add_request(req, &data->pages); | |
919 | ClearPageError(req->wb_page); | |
920 | *pages++ = req->wb_page; | |
921 | } | |
922 | req = nfs_list_entry(data->pages.next); | |
923 | ||
924 | /* Set up the argument struct */ | |
925 | nfs_write_rpcsetup(req, data, &nfs_write_full_ops, count, 0, how); | |
926 | ||
927 | nfs_execute_write(data); | |
928 | return 0; | |
929 | out_bad: | |
930 | while (!list_empty(head)) { | |
931 | req = nfs_list_entry(head->next); | |
932 | nfs_list_remove_request(req); | |
933 | nfs_redirty_request(req); | |
934 | nfs_end_page_writeback(req->wb_page); | |
935 | nfs_clear_page_tag_locked(req); | |
936 | } | |
937 | return -ENOMEM; | |
938 | } | |
939 | ||
940 | static void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, | |
941 | struct inode *inode, int ioflags) | |
942 | { | |
943 | int wsize = NFS_SERVER(inode)->wsize; | |
944 | ||
945 | if (wsize < PAGE_CACHE_SIZE) | |
946 | nfs_pageio_init(pgio, inode, nfs_flush_multi, wsize, ioflags); | |
947 | else | |
948 | nfs_pageio_init(pgio, inode, nfs_flush_one, wsize, ioflags); | |
949 | } | |
950 | ||
951 | /* | |
952 | * Handle a write reply that flushed part of a page. | |
953 | */ | |
954 | static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata) | |
955 | { | |
956 | struct nfs_write_data *data = calldata; | |
957 | struct nfs_page *req = data->req; | |
958 | struct page *page = req->wb_page; | |
959 | ||
960 | dprintk("NFS: write (%s/%Ld %d@%Ld)", | |
961 | req->wb_context->path.dentry->d_inode->i_sb->s_id, | |
962 | (long long)NFS_FILEID(req->wb_context->path.dentry->d_inode), | |
963 | req->wb_bytes, | |
964 | (long long)req_offset(req)); | |
965 | ||
966 | if (nfs_writeback_done(task, data) != 0) | |
967 | return; | |
968 | ||
969 | if (task->tk_status < 0) { | |
970 | nfs_set_pageerror(page); | |
971 | req->wb_context->error = task->tk_status; | |
972 | dprintk(", error = %d\n", task->tk_status); | |
973 | goto out; | |
974 | } | |
975 | ||
976 | if (nfs_write_need_commit(data)) { | |
977 | spinlock_t *req_lock = &NFS_I(page->mapping->host)->req_lock; | |
978 | ||
979 | spin_lock(req_lock); | |
980 | if (test_bit(PG_NEED_RESCHED, &req->wb_flags)) { | |
981 | /* Do nothing we need to resend the writes */ | |
982 | } else if (!test_and_set_bit(PG_NEED_COMMIT, &req->wb_flags)) { | |
983 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
984 | dprintk(" defer commit\n"); | |
985 | } else if (memcmp(&req->wb_verf, &data->verf, sizeof(req->wb_verf))) { | |
986 | set_bit(PG_NEED_RESCHED, &req->wb_flags); | |
987 | clear_bit(PG_NEED_COMMIT, &req->wb_flags); | |
988 | dprintk(" server reboot detected\n"); | |
989 | } | |
990 | spin_unlock(req_lock); | |
991 | } else | |
992 | dprintk(" OK\n"); | |
993 | ||
994 | out: | |
995 | if (atomic_dec_and_test(&req->wb_complete)) | |
996 | nfs_writepage_release(req); | |
997 | } | |
998 | ||
999 | static const struct rpc_call_ops nfs_write_partial_ops = { | |
1000 | .rpc_call_done = nfs_writeback_done_partial, | |
1001 | .rpc_release = nfs_writedata_release, | |
1002 | }; | |
1003 | ||
1004 | /* | |
1005 | * Handle a write reply that flushes a whole page. | |
1006 | * | |
1007 | * FIXME: There is an inherent race with invalidate_inode_pages and | |
1008 | * writebacks since the page->count is kept > 1 for as long | |
1009 | * as the page has a write request pending. | |
1010 | */ | |
1011 | static void nfs_writeback_done_full(struct rpc_task *task, void *calldata) | |
1012 | { | |
1013 | struct nfs_write_data *data = calldata; | |
1014 | struct nfs_page *req; | |
1015 | struct page *page; | |
1016 | ||
1017 | if (nfs_writeback_done(task, data) != 0) | |
1018 | return; | |
1019 | ||
1020 | /* Update attributes as result of writeback. */ | |
1021 | while (!list_empty(&data->pages)) { | |
1022 | req = nfs_list_entry(data->pages.next); | |
1023 | nfs_list_remove_request(req); | |
1024 | page = req->wb_page; | |
1025 | ||
1026 | dprintk("NFS: write (%s/%Ld %d@%Ld)", | |
1027 | req->wb_context->path.dentry->d_inode->i_sb->s_id, | |
1028 | (long long)NFS_FILEID(req->wb_context->path.dentry->d_inode), | |
1029 | req->wb_bytes, | |
1030 | (long long)req_offset(req)); | |
1031 | ||
1032 | if (task->tk_status < 0) { | |
1033 | nfs_set_pageerror(page); | |
1034 | req->wb_context->error = task->tk_status; | |
1035 | dprintk(", error = %d\n", task->tk_status); | |
1036 | goto remove_request; | |
1037 | } | |
1038 | ||
1039 | if (nfs_write_need_commit(data)) { | |
1040 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1041 | nfs_mark_request_commit(req); | |
1042 | nfs_end_page_writeback(page); | |
1043 | dprintk(" marked for commit\n"); | |
1044 | goto next; | |
1045 | } | |
1046 | /* Set the PG_uptodate flag? */ | |
1047 | nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes); | |
1048 | dprintk(" OK\n"); | |
1049 | remove_request: | |
1050 | nfs_end_page_writeback(page); | |
1051 | nfs_inode_remove_request(req); | |
1052 | next: | |
1053 | nfs_clear_page_tag_locked(req); | |
1054 | } | |
1055 | } | |
1056 | ||
1057 | static const struct rpc_call_ops nfs_write_full_ops = { | |
1058 | .rpc_call_done = nfs_writeback_done_full, | |
1059 | .rpc_release = nfs_writedata_release, | |
1060 | }; | |
1061 | ||
1062 | ||
1063 | /* | |
1064 | * This function is called when the WRITE call is complete. | |
1065 | */ | |
1066 | int nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data) | |
1067 | { | |
1068 | struct nfs_writeargs *argp = &data->args; | |
1069 | struct nfs_writeres *resp = &data->res; | |
1070 | int status; | |
1071 | ||
1072 | dprintk("NFS: %5u nfs_writeback_done (status %d)\n", | |
1073 | task->tk_pid, task->tk_status); | |
1074 | ||
1075 | /* | |
1076 | * ->write_done will attempt to use post-op attributes to detect | |
1077 | * conflicting writes by other clients. A strict interpretation | |
1078 | * of close-to-open would allow us to continue caching even if | |
1079 | * another writer had changed the file, but some applications | |
1080 | * depend on tighter cache coherency when writing. | |
1081 | */ | |
1082 | status = NFS_PROTO(data->inode)->write_done(task, data); | |
1083 | if (status != 0) | |
1084 | return status; | |
1085 | nfs_add_stats(data->inode, NFSIOS_SERVERWRITTENBYTES, resp->count); | |
1086 | ||
1087 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1088 | if (resp->verf->committed < argp->stable && task->tk_status >= 0) { | |
1089 | /* We tried a write call, but the server did not | |
1090 | * commit data to stable storage even though we | |
1091 | * requested it. | |
1092 | * Note: There is a known bug in Tru64 < 5.0 in which | |
1093 | * the server reports NFS_DATA_SYNC, but performs | |
1094 | * NFS_FILE_SYNC. We therefore implement this checking | |
1095 | * as a dprintk() in order to avoid filling syslog. | |
1096 | */ | |
1097 | static unsigned long complain; | |
1098 | ||
1099 | if (time_before(complain, jiffies)) { | |
1100 | dprintk("NFS: faulty NFS server %s:" | |
1101 | " (committed = %d) != (stable = %d)\n", | |
1102 | NFS_SERVER(data->inode)->nfs_client->cl_hostname, | |
1103 | resp->verf->committed, argp->stable); | |
1104 | complain = jiffies + 300 * HZ; | |
1105 | } | |
1106 | } | |
1107 | #endif | |
1108 | /* Is this a short write? */ | |
1109 | if (task->tk_status >= 0 && resp->count < argp->count) { | |
1110 | static unsigned long complain; | |
1111 | ||
1112 | nfs_inc_stats(data->inode, NFSIOS_SHORTWRITE); | |
1113 | ||
1114 | /* Has the server at least made some progress? */ | |
1115 | if (resp->count != 0) { | |
1116 | /* Was this an NFSv2 write or an NFSv3 stable write? */ | |
1117 | if (resp->verf->committed != NFS_UNSTABLE) { | |
1118 | /* Resend from where the server left off */ | |
1119 | argp->offset += resp->count; | |
1120 | argp->pgbase += resp->count; | |
1121 | argp->count -= resp->count; | |
1122 | } else { | |
1123 | /* Resend as a stable write in order to avoid | |
1124 | * headaches in the case of a server crash. | |
1125 | */ | |
1126 | argp->stable = NFS_FILE_SYNC; | |
1127 | } | |
1128 | rpc_restart_call(task); | |
1129 | return -EAGAIN; | |
1130 | } | |
1131 | if (time_before(complain, jiffies)) { | |
1132 | printk(KERN_WARNING | |
1133 | "NFS: Server wrote zero bytes, expected %u.\n", | |
1134 | argp->count); | |
1135 | complain = jiffies + 300 * HZ; | |
1136 | } | |
1137 | /* Can't do anything about it except throw an error. */ | |
1138 | task->tk_status = -EIO; | |
1139 | } | |
1140 | return 0; | |
1141 | } | |
1142 | ||
1143 | ||
1144 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1145 | void nfs_commit_release(void *wdata) | |
1146 | { | |
1147 | nfs_commit_free(wdata); | |
1148 | } | |
1149 | ||
1150 | /* | |
1151 | * Set up the argument/result storage required for the RPC call. | |
1152 | */ | |
1153 | static void nfs_commit_rpcsetup(struct list_head *head, | |
1154 | struct nfs_write_data *data, | |
1155 | int how) | |
1156 | { | |
1157 | struct nfs_page *first; | |
1158 | struct inode *inode; | |
1159 | int flags; | |
1160 | ||
1161 | /* Set up the RPC argument and reply structs | |
1162 | * NB: take care not to mess about with data->commit et al. */ | |
1163 | ||
1164 | list_splice_init(head, &data->pages); | |
1165 | first = nfs_list_entry(data->pages.next); | |
1166 | inode = first->wb_context->path.dentry->d_inode; | |
1167 | ||
1168 | data->inode = inode; | |
1169 | data->cred = first->wb_context->cred; | |
1170 | ||
1171 | data->args.fh = NFS_FH(data->inode); | |
1172 | /* Note: we always request a commit of the entire inode */ | |
1173 | data->args.offset = 0; | |
1174 | data->args.count = 0; | |
1175 | data->res.count = 0; | |
1176 | data->res.fattr = &data->fattr; | |
1177 | data->res.verf = &data->verf; | |
1178 | nfs_fattr_init(&data->fattr); | |
1179 | ||
1180 | /* Set up the initial task struct. */ | |
1181 | flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC; | |
1182 | rpc_init_task(&data->task, NFS_CLIENT(inode), flags, &nfs_commit_ops, data); | |
1183 | NFS_PROTO(inode)->commit_setup(data, how); | |
1184 | ||
1185 | data->task.tk_priority = flush_task_priority(how); | |
1186 | data->task.tk_cookie = (unsigned long)inode; | |
1187 | ||
1188 | dprintk("NFS: %5u initiated commit call\n", data->task.tk_pid); | |
1189 | } | |
1190 | ||
1191 | /* | |
1192 | * Commit dirty pages | |
1193 | */ | |
1194 | static int | |
1195 | nfs_commit_list(struct inode *inode, struct list_head *head, int how) | |
1196 | { | |
1197 | struct nfs_write_data *data; | |
1198 | struct nfs_page *req; | |
1199 | ||
1200 | data = nfs_commit_alloc(); | |
1201 | ||
1202 | if (!data) | |
1203 | goto out_bad; | |
1204 | ||
1205 | /* Set up the argument struct */ | |
1206 | nfs_commit_rpcsetup(head, data, how); | |
1207 | ||
1208 | nfs_execute_write(data); | |
1209 | return 0; | |
1210 | out_bad: | |
1211 | while (!list_empty(head)) { | |
1212 | req = nfs_list_entry(head->next); | |
1213 | nfs_list_remove_request(req); | |
1214 | nfs_mark_request_commit(req); | |
1215 | dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS); | |
1216 | nfs_clear_page_tag_locked(req); | |
1217 | } | |
1218 | return -ENOMEM; | |
1219 | } | |
1220 | ||
1221 | /* | |
1222 | * COMMIT call returned | |
1223 | */ | |
1224 | static void nfs_commit_done(struct rpc_task *task, void *calldata) | |
1225 | { | |
1226 | struct nfs_write_data *data = calldata; | |
1227 | struct nfs_page *req; | |
1228 | ||
1229 | dprintk("NFS: %5u nfs_commit_done (status %d)\n", | |
1230 | task->tk_pid, task->tk_status); | |
1231 | ||
1232 | /* Call the NFS version-specific code */ | |
1233 | if (NFS_PROTO(data->inode)->commit_done(task, data) != 0) | |
1234 | return; | |
1235 | ||
1236 | while (!list_empty(&data->pages)) { | |
1237 | req = nfs_list_entry(data->pages.next); | |
1238 | nfs_list_remove_request(req); | |
1239 | clear_bit(PG_NEED_COMMIT, &(req)->wb_flags); | |
1240 | dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS); | |
1241 | ||
1242 | dprintk("NFS: commit (%s/%Ld %d@%Ld)", | |
1243 | req->wb_context->path.dentry->d_inode->i_sb->s_id, | |
1244 | (long long)NFS_FILEID(req->wb_context->path.dentry->d_inode), | |
1245 | req->wb_bytes, | |
1246 | (long long)req_offset(req)); | |
1247 | if (task->tk_status < 0) { | |
1248 | req->wb_context->error = task->tk_status; | |
1249 | nfs_inode_remove_request(req); | |
1250 | dprintk(", error = %d\n", task->tk_status); | |
1251 | goto next; | |
1252 | } | |
1253 | ||
1254 | /* Okay, COMMIT succeeded, apparently. Check the verifier | |
1255 | * returned by the server against all stored verfs. */ | |
1256 | if (!memcmp(req->wb_verf.verifier, data->verf.verifier, sizeof(data->verf.verifier))) { | |
1257 | /* We have a match */ | |
1258 | /* Set the PG_uptodate flag */ | |
1259 | nfs_mark_uptodate(req->wb_page, req->wb_pgbase, | |
1260 | req->wb_bytes); | |
1261 | nfs_inode_remove_request(req); | |
1262 | dprintk(" OK\n"); | |
1263 | goto next; | |
1264 | } | |
1265 | /* We have a mismatch. Write the page again */ | |
1266 | dprintk(" mismatch\n"); | |
1267 | nfs_redirty_request(req); | |
1268 | next: | |
1269 | nfs_clear_page_tag_locked(req); | |
1270 | } | |
1271 | } | |
1272 | ||
1273 | static const struct rpc_call_ops nfs_commit_ops = { | |
1274 | .rpc_call_done = nfs_commit_done, | |
1275 | .rpc_release = nfs_commit_release, | |
1276 | }; | |
1277 | ||
1278 | int nfs_commit_inode(struct inode *inode, int how) | |
1279 | { | |
1280 | struct nfs_inode *nfsi = NFS_I(inode); | |
1281 | LIST_HEAD(head); | |
1282 | int res; | |
1283 | ||
1284 | spin_lock(&nfsi->req_lock); | |
1285 | res = nfs_scan_commit(inode, &head, 0, 0); | |
1286 | spin_unlock(&nfsi->req_lock); | |
1287 | if (res) { | |
1288 | int error = nfs_commit_list(inode, &head, how); | |
1289 | if (error < 0) | |
1290 | return error; | |
1291 | } | |
1292 | return res; | |
1293 | } | |
1294 | #else | |
1295 | static inline int nfs_commit_list(struct inode *inode, struct list_head *head, int how) | |
1296 | { | |
1297 | return 0; | |
1298 | } | |
1299 | #endif | |
1300 | ||
1301 | long nfs_sync_mapping_wait(struct address_space *mapping, struct writeback_control *wbc, int how) | |
1302 | { | |
1303 | struct inode *inode = mapping->host; | |
1304 | struct nfs_inode *nfsi = NFS_I(inode); | |
1305 | pgoff_t idx_start, idx_end; | |
1306 | unsigned int npages = 0; | |
1307 | LIST_HEAD(head); | |
1308 | int nocommit = how & FLUSH_NOCOMMIT; | |
1309 | long pages, ret; | |
1310 | ||
1311 | /* FIXME */ | |
1312 | if (wbc->range_cyclic) | |
1313 | idx_start = 0; | |
1314 | else { | |
1315 | idx_start = wbc->range_start >> PAGE_CACHE_SHIFT; | |
1316 | idx_end = wbc->range_end >> PAGE_CACHE_SHIFT; | |
1317 | if (idx_end > idx_start) { | |
1318 | pgoff_t l_npages = 1 + idx_end - idx_start; | |
1319 | npages = l_npages; | |
1320 | if (sizeof(npages) != sizeof(l_npages) && | |
1321 | (pgoff_t)npages != l_npages) | |
1322 | npages = 0; | |
1323 | } | |
1324 | } | |
1325 | how &= ~FLUSH_NOCOMMIT; | |
1326 | spin_lock(&nfsi->req_lock); | |
1327 | do { | |
1328 | ret = nfs_wait_on_requests_locked(inode, idx_start, npages); | |
1329 | if (ret != 0) | |
1330 | continue; | |
1331 | if (nocommit) | |
1332 | break; | |
1333 | pages = nfs_scan_commit(inode, &head, idx_start, npages); | |
1334 | if (pages == 0) | |
1335 | break; | |
1336 | if (how & FLUSH_INVALIDATE) { | |
1337 | spin_unlock(&nfsi->req_lock); | |
1338 | nfs_cancel_commit_list(&head); | |
1339 | ret = pages; | |
1340 | spin_lock(&nfsi->req_lock); | |
1341 | continue; | |
1342 | } | |
1343 | pages += nfs_scan_commit(inode, &head, 0, 0); | |
1344 | spin_unlock(&nfsi->req_lock); | |
1345 | ret = nfs_commit_list(inode, &head, how); | |
1346 | spin_lock(&nfsi->req_lock); | |
1347 | } while (ret >= 0); | |
1348 | spin_unlock(&nfsi->req_lock); | |
1349 | return ret; | |
1350 | } | |
1351 | ||
1352 | /* | |
1353 | * flush the inode to disk. | |
1354 | */ | |
1355 | int nfs_wb_all(struct inode *inode) | |
1356 | { | |
1357 | struct address_space *mapping = inode->i_mapping; | |
1358 | struct writeback_control wbc = { | |
1359 | .bdi = mapping->backing_dev_info, | |
1360 | .sync_mode = WB_SYNC_ALL, | |
1361 | .nr_to_write = LONG_MAX, | |
1362 | .for_writepages = 1, | |
1363 | .range_cyclic = 1, | |
1364 | }; | |
1365 | int ret; | |
1366 | ||
1367 | ret = nfs_writepages(mapping, &wbc); | |
1368 | if (ret < 0) | |
1369 | goto out; | |
1370 | ret = nfs_sync_mapping_wait(mapping, &wbc, 0); | |
1371 | if (ret >= 0) | |
1372 | return 0; | |
1373 | out: | |
1374 | __mark_inode_dirty(mapping->host, I_DIRTY_PAGES); | |
1375 | return ret; | |
1376 | } | |
1377 | ||
1378 | int nfs_sync_mapping_range(struct address_space *mapping, loff_t range_start, loff_t range_end, int how) | |
1379 | { | |
1380 | struct writeback_control wbc = { | |
1381 | .bdi = mapping->backing_dev_info, | |
1382 | .sync_mode = WB_SYNC_ALL, | |
1383 | .nr_to_write = LONG_MAX, | |
1384 | .range_start = range_start, | |
1385 | .range_end = range_end, | |
1386 | .for_writepages = 1, | |
1387 | }; | |
1388 | int ret; | |
1389 | ||
1390 | ret = nfs_writepages(mapping, &wbc); | |
1391 | if (ret < 0) | |
1392 | goto out; | |
1393 | ret = nfs_sync_mapping_wait(mapping, &wbc, how); | |
1394 | if (ret >= 0) | |
1395 | return 0; | |
1396 | out: | |
1397 | __mark_inode_dirty(mapping->host, I_DIRTY_PAGES); | |
1398 | return ret; | |
1399 | } | |
1400 | ||
1401 | int nfs_wb_page_priority(struct inode *inode, struct page *page, int how) | |
1402 | { | |
1403 | loff_t range_start = page_offset(page); | |
1404 | loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1); | |
1405 | struct writeback_control wbc = { | |
1406 | .bdi = page->mapping->backing_dev_info, | |
1407 | .sync_mode = WB_SYNC_ALL, | |
1408 | .nr_to_write = LONG_MAX, | |
1409 | .range_start = range_start, | |
1410 | .range_end = range_end, | |
1411 | }; | |
1412 | int ret; | |
1413 | ||
1414 | BUG_ON(!PageLocked(page)); | |
1415 | if (clear_page_dirty_for_io(page)) { | |
1416 | ret = nfs_writepage_locked(page, &wbc); | |
1417 | if (ret < 0) | |
1418 | goto out; | |
1419 | } | |
1420 | if (!PagePrivate(page)) | |
1421 | return 0; | |
1422 | ret = nfs_sync_mapping_wait(page->mapping, &wbc, how); | |
1423 | if (ret >= 0) | |
1424 | return 0; | |
1425 | out: | |
1426 | __mark_inode_dirty(inode, I_DIRTY_PAGES); | |
1427 | return ret; | |
1428 | } | |
1429 | ||
1430 | /* | |
1431 | * Write back all requests on one page - we do this before reading it. | |
1432 | */ | |
1433 | int nfs_wb_page(struct inode *inode, struct page* page) | |
1434 | { | |
1435 | return nfs_wb_page_priority(inode, page, FLUSH_STABLE); | |
1436 | } | |
1437 | ||
1438 | int nfs_set_page_dirty(struct page *page) | |
1439 | { | |
1440 | struct address_space *mapping = page->mapping; | |
1441 | struct inode *inode; | |
1442 | spinlock_t *req_lock; | |
1443 | struct nfs_page *req; | |
1444 | int ret; | |
1445 | ||
1446 | if (!mapping) | |
1447 | goto out_raced; | |
1448 | inode = mapping->host; | |
1449 | if (!inode) | |
1450 | goto out_raced; | |
1451 | req_lock = &NFS_I(inode)->req_lock; | |
1452 | spin_lock(req_lock); | |
1453 | req = nfs_page_find_request_locked(page); | |
1454 | if (req != NULL) { | |
1455 | /* Mark any existing write requests for flushing */ | |
1456 | ret = !test_and_set_bit(PG_NEED_FLUSH, &req->wb_flags); | |
1457 | spin_unlock(req_lock); | |
1458 | nfs_release_request(req); | |
1459 | return ret; | |
1460 | } | |
1461 | ret = __set_page_dirty_nobuffers(page); | |
1462 | spin_unlock(req_lock); | |
1463 | return ret; | |
1464 | out_raced: | |
1465 | return !TestSetPageDirty(page); | |
1466 | } | |
1467 | ||
1468 | ||
1469 | int __init nfs_init_writepagecache(void) | |
1470 | { | |
1471 | nfs_wdata_cachep = kmem_cache_create("nfs_write_data", | |
1472 | sizeof(struct nfs_write_data), | |
1473 | 0, SLAB_HWCACHE_ALIGN, | |
1474 | NULL, NULL); | |
1475 | if (nfs_wdata_cachep == NULL) | |
1476 | return -ENOMEM; | |
1477 | ||
1478 | nfs_wdata_mempool = mempool_create_slab_pool(MIN_POOL_WRITE, | |
1479 | nfs_wdata_cachep); | |
1480 | if (nfs_wdata_mempool == NULL) | |
1481 | return -ENOMEM; | |
1482 | ||
1483 | nfs_commit_mempool = mempool_create_slab_pool(MIN_POOL_COMMIT, | |
1484 | nfs_wdata_cachep); | |
1485 | if (nfs_commit_mempool == NULL) | |
1486 | return -ENOMEM; | |
1487 | ||
1488 | /* | |
1489 | * NFS congestion size, scale with available memory. | |
1490 | * | |
1491 | * 64MB: 8192k | |
1492 | * 128MB: 11585k | |
1493 | * 256MB: 16384k | |
1494 | * 512MB: 23170k | |
1495 | * 1GB: 32768k | |
1496 | * 2GB: 46340k | |
1497 | * 4GB: 65536k | |
1498 | * 8GB: 92681k | |
1499 | * 16GB: 131072k | |
1500 | * | |
1501 | * This allows larger machines to have larger/more transfers. | |
1502 | * Limit the default to 256M | |
1503 | */ | |
1504 | nfs_congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10); | |
1505 | if (nfs_congestion_kb > 256*1024) | |
1506 | nfs_congestion_kb = 256*1024; | |
1507 | ||
1508 | return 0; | |
1509 | } | |
1510 | ||
1511 | void nfs_destroy_writepagecache(void) | |
1512 | { | |
1513 | mempool_destroy(nfs_commit_mempool); | |
1514 | mempool_destroy(nfs_wdata_mempool); | |
1515 | kmem_cache_destroy(nfs_wdata_cachep); | |
1516 | } | |
1517 |