]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/nfs/write.c | |
3 | * | |
4 | * Writing file data over NFS. | |
5 | * | |
6 | * We do it like this: When a (user) process wishes to write data to an | |
7 | * NFS file, a write request is allocated that contains the RPC task data | |
8 | * plus some info on the page to be written, and added to the inode's | |
9 | * write chain. If the process writes past the end of the page, an async | |
10 | * RPC call to write the page is scheduled immediately; otherwise, the call | |
11 | * is delayed for a few seconds. | |
12 | * | |
13 | * Just like readahead, no async I/O is performed if wsize < PAGE_SIZE. | |
14 | * | |
15 | * Write requests are kept on the inode's writeback list. Each entry in | |
16 | * that list references the page (portion) to be written. When the | |
17 | * cache timeout has expired, the RPC task is woken up, and tries to | |
18 | * lock the page. As soon as it manages to do so, the request is moved | |
19 | * from the writeback list to the writelock list. | |
20 | * | |
21 | * Note: we must make sure never to confuse the inode passed in the | |
22 | * write_page request with the one in page->inode. As far as I understand | |
23 | * it, these are different when doing a swap-out. | |
24 | * | |
25 | * To understand everything that goes on here and in the NFS read code, | |
26 | * one should be aware that a page is locked in exactly one of the following | |
27 | * cases: | |
28 | * | |
29 | * - A write request is in progress. | |
30 | * - A user process is in generic_file_write/nfs_update_page | |
31 | * - A user process is in generic_file_read | |
32 | * | |
33 | * Also note that because of the way pages are invalidated in | |
34 | * nfs_revalidate_inode, the following assertions hold: | |
35 | * | |
36 | * - If a page is dirty, there will be no read requests (a page will | |
37 | * not be re-read unless invalidated by nfs_revalidate_inode). | |
38 | * - If the page is not uptodate, there will be no pending write | |
39 | * requests, and no process will be in nfs_update_page. | |
40 | * | |
41 | * FIXME: Interaction with the vmscan routines is not optimal yet. | |
42 | * Either vmscan must be made nfs-savvy, or we need a different page | |
43 | * reclaim concept that supports something like FS-independent | |
44 | * buffer_heads with a b_ops-> field. | |
45 | * | |
46 | * Copyright (C) 1996, 1997, Olaf Kirch <okir@monad.swb.de> | |
47 | */ | |
48 | ||
49 | #include <linux/config.h> | |
50 | #include <linux/types.h> | |
51 | #include <linux/slab.h> | |
52 | #include <linux/mm.h> | |
53 | #include <linux/pagemap.h> | |
54 | #include <linux/file.h> | |
55 | #include <linux/mpage.h> | |
56 | #include <linux/writeback.h> | |
57 | ||
58 | #include <linux/sunrpc/clnt.h> | |
59 | #include <linux/nfs_fs.h> | |
60 | #include <linux/nfs_mount.h> | |
61 | #include <linux/nfs_page.h> | |
62 | #include <asm/uaccess.h> | |
63 | #include <linux/smp_lock.h> | |
64 | ||
65 | #include "delegation.h" | |
91d5b470 | 66 | #include "iostat.h" |
1da177e4 LT |
67 | |
68 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE | |
69 | ||
70 | #define MIN_POOL_WRITE (32) | |
71 | #define MIN_POOL_COMMIT (4) | |
72 | ||
73 | /* | |
74 | * Local function declarations | |
75 | */ | |
76 | static struct nfs_page * nfs_update_request(struct nfs_open_context*, | |
77 | struct inode *, | |
78 | struct page *, | |
79 | unsigned int, unsigned int); | |
80 | static void nfs_writeback_done_partial(struct nfs_write_data *, int); | |
81 | static void nfs_writeback_done_full(struct nfs_write_data *, int); | |
82 | static int nfs_wait_on_write_congestion(struct address_space *, int); | |
83 | static int nfs_wait_on_requests(struct inode *, unsigned long, unsigned int); | |
84 | static int nfs_flush_inode(struct inode *inode, unsigned long idx_start, | |
85 | unsigned int npages, int how); | |
86 | ||
87 | static kmem_cache_t *nfs_wdata_cachep; | |
88 | mempool_t *nfs_wdata_mempool; | |
89 | static mempool_t *nfs_commit_mempool; | |
90 | ||
91 | static DECLARE_WAIT_QUEUE_HEAD(nfs_write_congestion); | |
92 | ||
40859d7e | 93 | static inline struct nfs_write_data *nfs_commit_alloc(unsigned int pagecount) |
1da177e4 LT |
94 | { |
95 | struct nfs_write_data *p = mempool_alloc(nfs_commit_mempool, SLAB_NOFS); | |
40859d7e | 96 | |
1da177e4 LT |
97 | if (p) { |
98 | memset(p, 0, sizeof(*p)); | |
99 | INIT_LIST_HEAD(&p->pages); | |
40859d7e CL |
100 | if (pagecount < NFS_PAGEVEC_SIZE) |
101 | p->pagevec = &p->page_array[0]; | |
102 | else { | |
103 | size_t size = ++pagecount * sizeof(struct page *); | |
bd647545 ES |
104 | p->pagevec = kzalloc(size, GFP_NOFS); |
105 | if (!p->pagevec) { | |
40859d7e CL |
106 | mempool_free(p, nfs_commit_mempool); |
107 | p = NULL; | |
108 | } | |
109 | } | |
1da177e4 LT |
110 | } |
111 | return p; | |
112 | } | |
113 | ||
114 | static inline void nfs_commit_free(struct nfs_write_data *p) | |
115 | { | |
40859d7e CL |
116 | if (p && (p->pagevec != &p->page_array[0])) |
117 | kfree(p->pagevec); | |
1da177e4 LT |
118 | mempool_free(p, nfs_commit_mempool); |
119 | } | |
120 | ||
963d8fe5 | 121 | void nfs_writedata_release(void *wdata) |
1da177e4 | 122 | { |
1da177e4 LT |
123 | nfs_writedata_free(wdata); |
124 | } | |
125 | ||
126 | /* Adjust the file length if we're writing beyond the end */ | |
127 | static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count) | |
128 | { | |
129 | struct inode *inode = page->mapping->host; | |
130 | loff_t end, i_size = i_size_read(inode); | |
131 | unsigned long end_index = (i_size - 1) >> PAGE_CACHE_SHIFT; | |
132 | ||
133 | if (i_size > 0 && page->index < end_index) | |
134 | return; | |
135 | end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + ((loff_t)offset+count); | |
136 | if (i_size >= end) | |
137 | return; | |
91d5b470 | 138 | nfs_inc_stats(inode, NFSIOS_EXTENDWRITE); |
1da177e4 LT |
139 | i_size_write(inode, end); |
140 | } | |
141 | ||
142 | /* We can set the PG_uptodate flag if we see that a write request | |
143 | * covers the full page. | |
144 | */ | |
145 | static void nfs_mark_uptodate(struct page *page, unsigned int base, unsigned int count) | |
146 | { | |
147 | loff_t end_offs; | |
148 | ||
149 | if (PageUptodate(page)) | |
150 | return; | |
151 | if (base != 0) | |
152 | return; | |
153 | if (count == PAGE_CACHE_SIZE) { | |
154 | SetPageUptodate(page); | |
155 | return; | |
156 | } | |
157 | ||
158 | end_offs = i_size_read(page->mapping->host) - 1; | |
159 | if (end_offs < 0) | |
160 | return; | |
161 | /* Is this the last page? */ | |
162 | if (page->index != (unsigned long)(end_offs >> PAGE_CACHE_SHIFT)) | |
163 | return; | |
164 | /* This is the last page: set PG_uptodate if we cover the entire | |
165 | * extent of the data, then zero the rest of the page. | |
166 | */ | |
167 | if (count == (unsigned int)(end_offs & (PAGE_CACHE_SIZE - 1)) + 1) { | |
168 | memclear_highpage_flush(page, count, PAGE_CACHE_SIZE - count); | |
169 | SetPageUptodate(page); | |
170 | } | |
171 | } | |
172 | ||
173 | /* | |
174 | * Write a page synchronously. | |
175 | * Offset is the data offset within the page. | |
176 | */ | |
177 | static int nfs_writepage_sync(struct nfs_open_context *ctx, struct inode *inode, | |
178 | struct page *page, unsigned int offset, unsigned int count, | |
179 | int how) | |
180 | { | |
181 | unsigned int wsize = NFS_SERVER(inode)->wsize; | |
182 | int result, written = 0; | |
183 | struct nfs_write_data *wdata; | |
184 | ||
40859d7e | 185 | wdata = nfs_writedata_alloc(1); |
1da177e4 LT |
186 | if (!wdata) |
187 | return -ENOMEM; | |
188 | ||
189 | wdata->flags = how; | |
190 | wdata->cred = ctx->cred; | |
191 | wdata->inode = inode; | |
192 | wdata->args.fh = NFS_FH(inode); | |
193 | wdata->args.context = ctx; | |
194 | wdata->args.pages = &page; | |
195 | wdata->args.stable = NFS_FILE_SYNC; | |
196 | wdata->args.pgbase = offset; | |
197 | wdata->args.count = wsize; | |
198 | wdata->res.fattr = &wdata->fattr; | |
199 | wdata->res.verf = &wdata->verf; | |
200 | ||
201 | dprintk("NFS: nfs_writepage_sync(%s/%Ld %d@%Ld)\n", | |
202 | inode->i_sb->s_id, | |
203 | (long long)NFS_FILEID(inode), | |
204 | count, (long long)(page_offset(page) + offset)); | |
205 | ||
bb713d6d | 206 | set_page_writeback(page); |
1da177e4 LT |
207 | nfs_begin_data_update(inode); |
208 | do { | |
209 | if (count < wsize) | |
210 | wdata->args.count = count; | |
211 | wdata->args.offset = page_offset(page) + wdata->args.pgbase; | |
212 | ||
213 | result = NFS_PROTO(inode)->write(wdata); | |
214 | ||
215 | if (result < 0) { | |
216 | /* Must mark the page invalid after I/O error */ | |
217 | ClearPageUptodate(page); | |
218 | goto io_error; | |
219 | } | |
220 | if (result < wdata->args.count) | |
221 | printk(KERN_WARNING "NFS: short write, count=%u, result=%d\n", | |
222 | wdata->args.count, result); | |
223 | ||
224 | wdata->args.offset += result; | |
225 | wdata->args.pgbase += result; | |
226 | written += result; | |
227 | count -= result; | |
91d5b470 | 228 | nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, result); |
1da177e4 LT |
229 | } while (count); |
230 | /* Update file length */ | |
231 | nfs_grow_file(page, offset, written); | |
232 | /* Set the PG_uptodate flag? */ | |
233 | nfs_mark_uptodate(page, offset, written); | |
234 | ||
235 | if (PageError(page)) | |
236 | ClearPageError(page); | |
237 | ||
238 | io_error: | |
951a143b | 239 | nfs_end_data_update(inode); |
bb713d6d | 240 | end_page_writeback(page); |
1da177e4 LT |
241 | nfs_writedata_free(wdata); |
242 | return written ? written : result; | |
243 | } | |
244 | ||
245 | static int nfs_writepage_async(struct nfs_open_context *ctx, | |
246 | struct inode *inode, struct page *page, | |
247 | unsigned int offset, unsigned int count) | |
248 | { | |
249 | struct nfs_page *req; | |
1da177e4 LT |
250 | |
251 | req = nfs_update_request(ctx, inode, page, offset, count); | |
abd3e641 TM |
252 | if (IS_ERR(req)) |
253 | return PTR_ERR(req); | |
1da177e4 LT |
254 | /* Update file length */ |
255 | nfs_grow_file(page, offset, count); | |
256 | /* Set the PG_uptodate flag? */ | |
257 | nfs_mark_uptodate(page, offset, count); | |
258 | nfs_unlock_request(req); | |
abd3e641 | 259 | return 0; |
1da177e4 LT |
260 | } |
261 | ||
262 | static int wb_priority(struct writeback_control *wbc) | |
263 | { | |
264 | if (wbc->for_reclaim) | |
265 | return FLUSH_HIGHPRI; | |
266 | if (wbc->for_kupdate) | |
267 | return FLUSH_LOWPRI; | |
268 | return 0; | |
269 | } | |
270 | ||
271 | /* | |
272 | * Write an mmapped page to the server. | |
273 | */ | |
274 | int nfs_writepage(struct page *page, struct writeback_control *wbc) | |
275 | { | |
276 | struct nfs_open_context *ctx; | |
277 | struct inode *inode = page->mapping->host; | |
278 | unsigned long end_index; | |
279 | unsigned offset = PAGE_CACHE_SIZE; | |
280 | loff_t i_size = i_size_read(inode); | |
281 | int inode_referenced = 0; | |
282 | int priority = wb_priority(wbc); | |
283 | int err; | |
284 | ||
91d5b470 CL |
285 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); |
286 | nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1); | |
287 | ||
1da177e4 LT |
288 | /* |
289 | * Note: We need to ensure that we have a reference to the inode | |
290 | * if we are to do asynchronous writes. If not, waiting | |
291 | * in nfs_wait_on_request() may deadlock with clear_inode(). | |
292 | * | |
293 | * If igrab() fails here, then it is in any case safe to | |
294 | * call nfs_wb_page(), since there will be no pending writes. | |
295 | */ | |
296 | if (igrab(inode) != 0) | |
297 | inode_referenced = 1; | |
298 | end_index = i_size >> PAGE_CACHE_SHIFT; | |
299 | ||
300 | /* Ensure we've flushed out any previous writes */ | |
301 | nfs_wb_page_priority(inode, page, priority); | |
302 | ||
303 | /* easy case */ | |
304 | if (page->index < end_index) | |
305 | goto do_it; | |
306 | /* things got complicated... */ | |
307 | offset = i_size & (PAGE_CACHE_SIZE-1); | |
308 | ||
309 | /* OK, are we completely out? */ | |
310 | err = 0; /* potential race with truncate - ignore */ | |
311 | if (page->index >= end_index+1 || !offset) | |
312 | goto out; | |
313 | do_it: | |
d530838b | 314 | ctx = nfs_find_open_context(inode, NULL, FMODE_WRITE); |
1da177e4 LT |
315 | if (ctx == NULL) { |
316 | err = -EBADF; | |
317 | goto out; | |
318 | } | |
319 | lock_kernel(); | |
320 | if (!IS_SYNC(inode) && inode_referenced) { | |
321 | err = nfs_writepage_async(ctx, inode, page, 0, offset); | |
abd3e641 TM |
322 | if (!wbc->for_writepages) |
323 | nfs_flush_inode(inode, 0, 0, wb_priority(wbc)); | |
1da177e4 LT |
324 | } else { |
325 | err = nfs_writepage_sync(ctx, inode, page, 0, | |
326 | offset, priority); | |
327 | if (err >= 0) { | |
328 | if (err != offset) | |
329 | redirty_page_for_writepage(wbc, page); | |
330 | err = 0; | |
331 | } | |
332 | } | |
333 | unlock_kernel(); | |
334 | put_nfs_open_context(ctx); | |
335 | out: | |
336 | unlock_page(page); | |
337 | if (inode_referenced) | |
338 | iput(inode); | |
339 | return err; | |
340 | } | |
341 | ||
342 | /* | |
343 | * Note: causes nfs_update_request() to block on the assumption | |
344 | * that the writeback is generated due to memory pressure. | |
345 | */ | |
346 | int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) | |
347 | { | |
348 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
349 | struct inode *inode = mapping->host; | |
350 | int err; | |
351 | ||
91d5b470 CL |
352 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); |
353 | ||
1da177e4 LT |
354 | err = generic_writepages(mapping, wbc); |
355 | if (err) | |
356 | return err; | |
357 | while (test_and_set_bit(BDI_write_congested, &bdi->state) != 0) { | |
358 | if (wbc->nonblocking) | |
359 | return 0; | |
360 | nfs_wait_on_write_congestion(mapping, 0); | |
361 | } | |
362 | err = nfs_flush_inode(inode, 0, 0, wb_priority(wbc)); | |
363 | if (err < 0) | |
364 | goto out; | |
91d5b470 | 365 | nfs_add_stats(inode, NFSIOS_WRITEPAGES, err); |
1da177e4 LT |
366 | wbc->nr_to_write -= err; |
367 | if (!wbc->nonblocking && wbc->sync_mode == WB_SYNC_ALL) { | |
368 | err = nfs_wait_on_requests(inode, 0, 0); | |
369 | if (err < 0) | |
370 | goto out; | |
371 | } | |
3da28eb1 | 372 | err = nfs_commit_inode(inode, wb_priority(wbc)); |
1da177e4 LT |
373 | if (err > 0) { |
374 | wbc->nr_to_write -= err; | |
375 | err = 0; | |
376 | } | |
377 | out: | |
378 | clear_bit(BDI_write_congested, &bdi->state); | |
379 | wake_up_all(&nfs_write_congestion); | |
380 | return err; | |
381 | } | |
382 | ||
383 | /* | |
384 | * Insert a write request into an inode | |
385 | */ | |
386 | static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req) | |
387 | { | |
388 | struct nfs_inode *nfsi = NFS_I(inode); | |
389 | int error; | |
390 | ||
391 | error = radix_tree_insert(&nfsi->nfs_page_tree, req->wb_index, req); | |
392 | BUG_ON(error == -EEXIST); | |
393 | if (error) | |
394 | return error; | |
395 | if (!nfsi->npages) { | |
396 | igrab(inode); | |
397 | nfs_begin_data_update(inode); | |
398 | if (nfs_have_delegation(inode, FMODE_WRITE)) | |
399 | nfsi->change_attr++; | |
400 | } | |
401 | nfsi->npages++; | |
402 | atomic_inc(&req->wb_count); | |
403 | return 0; | |
404 | } | |
405 | ||
406 | /* | |
407 | * Insert a write request into an inode | |
408 | */ | |
409 | static void nfs_inode_remove_request(struct nfs_page *req) | |
410 | { | |
411 | struct inode *inode = req->wb_context->dentry->d_inode; | |
412 | struct nfs_inode *nfsi = NFS_I(inode); | |
413 | ||
414 | BUG_ON (!NFS_WBACK_BUSY(req)); | |
415 | ||
416 | spin_lock(&nfsi->req_lock); | |
417 | radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index); | |
418 | nfsi->npages--; | |
419 | if (!nfsi->npages) { | |
420 | spin_unlock(&nfsi->req_lock); | |
951a143b | 421 | nfs_end_data_update(inode); |
1da177e4 LT |
422 | iput(inode); |
423 | } else | |
424 | spin_unlock(&nfsi->req_lock); | |
425 | nfs_clear_request(req); | |
426 | nfs_release_request(req); | |
427 | } | |
428 | ||
429 | /* | |
430 | * Find a request | |
431 | */ | |
432 | static inline struct nfs_page * | |
433 | _nfs_find_request(struct inode *inode, unsigned long index) | |
434 | { | |
435 | struct nfs_inode *nfsi = NFS_I(inode); | |
436 | struct nfs_page *req; | |
437 | ||
438 | req = (struct nfs_page*)radix_tree_lookup(&nfsi->nfs_page_tree, index); | |
439 | if (req) | |
440 | atomic_inc(&req->wb_count); | |
441 | return req; | |
442 | } | |
443 | ||
444 | static struct nfs_page * | |
445 | nfs_find_request(struct inode *inode, unsigned long index) | |
446 | { | |
447 | struct nfs_page *req; | |
448 | struct nfs_inode *nfsi = NFS_I(inode); | |
449 | ||
450 | spin_lock(&nfsi->req_lock); | |
451 | req = _nfs_find_request(inode, index); | |
452 | spin_unlock(&nfsi->req_lock); | |
453 | return req; | |
454 | } | |
455 | ||
456 | /* | |
457 | * Add a request to the inode's dirty list. | |
458 | */ | |
459 | static void | |
460 | nfs_mark_request_dirty(struct nfs_page *req) | |
461 | { | |
462 | struct inode *inode = req->wb_context->dentry->d_inode; | |
463 | struct nfs_inode *nfsi = NFS_I(inode); | |
464 | ||
465 | spin_lock(&nfsi->req_lock); | |
3da28eb1 TM |
466 | radix_tree_tag_set(&nfsi->nfs_page_tree, |
467 | req->wb_index, NFS_PAGE_TAG_DIRTY); | |
1da177e4 LT |
468 | nfs_list_add_request(req, &nfsi->dirty); |
469 | nfsi->ndirty++; | |
470 | spin_unlock(&nfsi->req_lock); | |
471 | inc_page_state(nr_dirty); | |
472 | mark_inode_dirty(inode); | |
473 | } | |
474 | ||
475 | /* | |
476 | * Check if a request is dirty | |
477 | */ | |
478 | static inline int | |
479 | nfs_dirty_request(struct nfs_page *req) | |
480 | { | |
481 | struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode); | |
482 | return !list_empty(&req->wb_list) && req->wb_list_head == &nfsi->dirty; | |
483 | } | |
484 | ||
485 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
486 | /* | |
487 | * Add a request to the inode's commit list. | |
488 | */ | |
489 | static void | |
490 | nfs_mark_request_commit(struct nfs_page *req) | |
491 | { | |
492 | struct inode *inode = req->wb_context->dentry->d_inode; | |
493 | struct nfs_inode *nfsi = NFS_I(inode); | |
494 | ||
495 | spin_lock(&nfsi->req_lock); | |
496 | nfs_list_add_request(req, &nfsi->commit); | |
497 | nfsi->ncommit++; | |
498 | spin_unlock(&nfsi->req_lock); | |
499 | inc_page_state(nr_unstable); | |
500 | mark_inode_dirty(inode); | |
501 | } | |
502 | #endif | |
503 | ||
504 | /* | |
505 | * Wait for a request to complete. | |
506 | * | |
507 | * Interruptible by signals only if mounted with intr flag. | |
508 | */ | |
509 | static int | |
510 | nfs_wait_on_requests(struct inode *inode, unsigned long idx_start, unsigned int npages) | |
511 | { | |
512 | struct nfs_inode *nfsi = NFS_I(inode); | |
513 | struct nfs_page *req; | |
514 | unsigned long idx_end, next; | |
515 | unsigned int res = 0; | |
516 | int error; | |
517 | ||
518 | if (npages == 0) | |
519 | idx_end = ~0; | |
520 | else | |
521 | idx_end = idx_start + npages - 1; | |
522 | ||
523 | spin_lock(&nfsi->req_lock); | |
524 | next = idx_start; | |
c6a556b8 | 525 | while (radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree, (void **)&req, next, 1, NFS_PAGE_TAG_WRITEBACK)) { |
1da177e4 LT |
526 | if (req->wb_index > idx_end) |
527 | break; | |
528 | ||
529 | next = req->wb_index + 1; | |
c6a556b8 | 530 | BUG_ON(!NFS_WBACK_BUSY(req)); |
1da177e4 LT |
531 | |
532 | atomic_inc(&req->wb_count); | |
533 | spin_unlock(&nfsi->req_lock); | |
534 | error = nfs_wait_on_request(req); | |
535 | nfs_release_request(req); | |
536 | if (error < 0) | |
537 | return error; | |
538 | spin_lock(&nfsi->req_lock); | |
539 | res++; | |
540 | } | |
541 | spin_unlock(&nfsi->req_lock); | |
542 | return res; | |
543 | } | |
544 | ||
545 | /* | |
546 | * nfs_scan_dirty - Scan an inode for dirty requests | |
547 | * @inode: NFS inode to scan | |
548 | * @dst: destination list | |
549 | * @idx_start: lower bound of page->index to scan. | |
550 | * @npages: idx_start + npages sets the upper bound to scan. | |
551 | * | |
552 | * Moves requests from the inode's dirty page list. | |
553 | * The requests are *not* checked to ensure that they form a contiguous set. | |
554 | */ | |
555 | static int | |
556 | nfs_scan_dirty(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
557 | { | |
558 | struct nfs_inode *nfsi = NFS_I(inode); | |
3da28eb1 TM |
559 | int res = 0; |
560 | ||
561 | if (nfsi->ndirty != 0) { | |
562 | res = nfs_scan_lock_dirty(nfsi, dst, idx_start, npages); | |
563 | nfsi->ndirty -= res; | |
564 | sub_page_state(nr_dirty,res); | |
565 | if ((nfsi->ndirty == 0) != list_empty(&nfsi->dirty)) | |
566 | printk(KERN_ERR "NFS: desynchronized value of nfs_i.ndirty.\n"); | |
567 | } | |
1da177e4 LT |
568 | return res; |
569 | } | |
570 | ||
571 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
572 | /* | |
573 | * nfs_scan_commit - Scan an inode for commit requests | |
574 | * @inode: NFS inode to scan | |
575 | * @dst: destination list | |
576 | * @idx_start: lower bound of page->index to scan. | |
577 | * @npages: idx_start + npages sets the upper bound to scan. | |
578 | * | |
579 | * Moves requests from the inode's 'commit' request list. | |
580 | * The requests are *not* checked to ensure that they form a contiguous set. | |
581 | */ | |
582 | static int | |
583 | nfs_scan_commit(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
584 | { | |
585 | struct nfs_inode *nfsi = NFS_I(inode); | |
3da28eb1 TM |
586 | int res = 0; |
587 | ||
588 | if (nfsi->ncommit != 0) { | |
589 | res = nfs_scan_list(&nfsi->commit, dst, idx_start, npages); | |
590 | nfsi->ncommit -= res; | |
591 | if ((nfsi->ncommit == 0) != list_empty(&nfsi->commit)) | |
592 | printk(KERN_ERR "NFS: desynchronized value of nfs_i.ncommit.\n"); | |
593 | } | |
1da177e4 LT |
594 | return res; |
595 | } | |
596 | #endif | |
597 | ||
598 | static int nfs_wait_on_write_congestion(struct address_space *mapping, int intr) | |
599 | { | |
600 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
601 | DEFINE_WAIT(wait); | |
602 | int ret = 0; | |
603 | ||
604 | might_sleep(); | |
605 | ||
606 | if (!bdi_write_congested(bdi)) | |
607 | return 0; | |
91d5b470 CL |
608 | |
609 | nfs_inc_stats(mapping->host, NFSIOS_CONGESTIONWAIT); | |
610 | ||
1da177e4 LT |
611 | if (intr) { |
612 | struct rpc_clnt *clnt = NFS_CLIENT(mapping->host); | |
613 | sigset_t oldset; | |
614 | ||
615 | rpc_clnt_sigmask(clnt, &oldset); | |
616 | prepare_to_wait(&nfs_write_congestion, &wait, TASK_INTERRUPTIBLE); | |
617 | if (bdi_write_congested(bdi)) { | |
618 | if (signalled()) | |
619 | ret = -ERESTARTSYS; | |
620 | else | |
621 | schedule(); | |
622 | } | |
623 | rpc_clnt_sigunmask(clnt, &oldset); | |
624 | } else { | |
625 | prepare_to_wait(&nfs_write_congestion, &wait, TASK_UNINTERRUPTIBLE); | |
626 | if (bdi_write_congested(bdi)) | |
627 | schedule(); | |
628 | } | |
629 | finish_wait(&nfs_write_congestion, &wait); | |
630 | return ret; | |
631 | } | |
632 | ||
633 | ||
634 | /* | |
635 | * Try to update any existing write request, or create one if there is none. | |
636 | * In order to match, the request's credentials must match those of | |
637 | * the calling process. | |
638 | * | |
639 | * Note: Should always be called with the Page Lock held! | |
640 | */ | |
641 | static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx, | |
642 | struct inode *inode, struct page *page, | |
643 | unsigned int offset, unsigned int bytes) | |
644 | { | |
645 | struct nfs_server *server = NFS_SERVER(inode); | |
646 | struct nfs_inode *nfsi = NFS_I(inode); | |
647 | struct nfs_page *req, *new = NULL; | |
648 | unsigned long rqend, end; | |
649 | ||
650 | end = offset + bytes; | |
651 | ||
652 | if (nfs_wait_on_write_congestion(page->mapping, server->flags & NFS_MOUNT_INTR)) | |
653 | return ERR_PTR(-ERESTARTSYS); | |
654 | for (;;) { | |
655 | /* Loop over all inode entries and see if we find | |
656 | * A request for the page we wish to update | |
657 | */ | |
658 | spin_lock(&nfsi->req_lock); | |
659 | req = _nfs_find_request(inode, page->index); | |
660 | if (req) { | |
661 | if (!nfs_lock_request_dontget(req)) { | |
662 | int error; | |
663 | spin_unlock(&nfsi->req_lock); | |
664 | error = nfs_wait_on_request(req); | |
665 | nfs_release_request(req); | |
1dd594b2 NB |
666 | if (error < 0) { |
667 | if (new) | |
668 | nfs_release_request(new); | |
1da177e4 | 669 | return ERR_PTR(error); |
1dd594b2 | 670 | } |
1da177e4 LT |
671 | continue; |
672 | } | |
673 | spin_unlock(&nfsi->req_lock); | |
674 | if (new) | |
675 | nfs_release_request(new); | |
676 | break; | |
677 | } | |
678 | ||
679 | if (new) { | |
680 | int error; | |
681 | nfs_lock_request_dontget(new); | |
682 | error = nfs_inode_add_request(inode, new); | |
683 | if (error) { | |
684 | spin_unlock(&nfsi->req_lock); | |
685 | nfs_unlock_request(new); | |
686 | return ERR_PTR(error); | |
687 | } | |
688 | spin_unlock(&nfsi->req_lock); | |
689 | nfs_mark_request_dirty(new); | |
690 | return new; | |
691 | } | |
692 | spin_unlock(&nfsi->req_lock); | |
693 | ||
694 | new = nfs_create_request(ctx, inode, page, offset, bytes); | |
695 | if (IS_ERR(new)) | |
696 | return new; | |
697 | } | |
698 | ||
699 | /* We have a request for our page. | |
700 | * If the creds don't match, or the | |
701 | * page addresses don't match, | |
702 | * tell the caller to wait on the conflicting | |
703 | * request. | |
704 | */ | |
705 | rqend = req->wb_offset + req->wb_bytes; | |
706 | if (req->wb_context != ctx | |
707 | || req->wb_page != page | |
708 | || !nfs_dirty_request(req) | |
709 | || offset > rqend || end < req->wb_offset) { | |
710 | nfs_unlock_request(req); | |
711 | return ERR_PTR(-EBUSY); | |
712 | } | |
713 | ||
714 | /* Okay, the request matches. Update the region */ | |
715 | if (offset < req->wb_offset) { | |
716 | req->wb_offset = offset; | |
717 | req->wb_pgbase = offset; | |
718 | req->wb_bytes = rqend - req->wb_offset; | |
719 | } | |
720 | ||
721 | if (end > rqend) | |
722 | req->wb_bytes = end - req->wb_offset; | |
723 | ||
724 | return req; | |
725 | } | |
726 | ||
727 | int nfs_flush_incompatible(struct file *file, struct page *page) | |
728 | { | |
729 | struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data; | |
730 | struct inode *inode = page->mapping->host; | |
731 | struct nfs_page *req; | |
732 | int status = 0; | |
733 | /* | |
734 | * Look for a request corresponding to this page. If there | |
735 | * is one, and it belongs to another file, we flush it out | |
736 | * before we try to copy anything into the page. Do this | |
737 | * due to the lack of an ACCESS-type call in NFSv2. | |
738 | * Also do the same if we find a request from an existing | |
739 | * dropped page. | |
740 | */ | |
741 | req = nfs_find_request(inode, page->index); | |
742 | if (req) { | |
743 | if (req->wb_page != page || ctx != req->wb_context) | |
744 | status = nfs_wb_page(inode, page); | |
745 | nfs_release_request(req); | |
746 | } | |
747 | return (status < 0) ? status : 0; | |
748 | } | |
749 | ||
750 | /* | |
751 | * Update and possibly write a cached page of an NFS file. | |
752 | * | |
753 | * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad | |
754 | * things with a page scheduled for an RPC call (e.g. invalidate it). | |
755 | */ | |
756 | int nfs_updatepage(struct file *file, struct page *page, | |
757 | unsigned int offset, unsigned int count) | |
758 | { | |
759 | struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data; | |
1da177e4 LT |
760 | struct inode *inode = page->mapping->host; |
761 | struct nfs_page *req; | |
762 | int status = 0; | |
763 | ||
91d5b470 CL |
764 | nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE); |
765 | ||
1da177e4 | 766 | dprintk("NFS: nfs_updatepage(%s/%s %d@%Ld)\n", |
0bbacc40 CL |
767 | file->f_dentry->d_parent->d_name.name, |
768 | file->f_dentry->d_name.name, count, | |
769 | (long long)(page_offset(page) +offset)); | |
1da177e4 LT |
770 | |
771 | if (IS_SYNC(inode)) { | |
772 | status = nfs_writepage_sync(ctx, inode, page, offset, count, 0); | |
773 | if (status > 0) { | |
774 | if (offset == 0 && status == PAGE_CACHE_SIZE) | |
775 | SetPageUptodate(page); | |
776 | return 0; | |
777 | } | |
778 | return status; | |
779 | } | |
780 | ||
781 | /* If we're not using byte range locks, and we know the page | |
782 | * is entirely in cache, it may be more efficient to avoid | |
783 | * fragmenting write requests. | |
784 | */ | |
ab0a3dbe | 785 | if (PageUptodate(page) && inode->i_flock == NULL && !(file->f_mode & O_SYNC)) { |
1da177e4 LT |
786 | loff_t end_offs = i_size_read(inode) - 1; |
787 | unsigned long end_index = end_offs >> PAGE_CACHE_SHIFT; | |
788 | ||
789 | count += offset; | |
790 | offset = 0; | |
791 | if (unlikely(end_offs < 0)) { | |
792 | /* Do nothing */ | |
793 | } else if (page->index == end_index) { | |
794 | unsigned int pglen; | |
795 | pglen = (unsigned int)(end_offs & (PAGE_CACHE_SIZE-1)) + 1; | |
796 | if (count < pglen) | |
797 | count = pglen; | |
798 | } else if (page->index < end_index) | |
799 | count = PAGE_CACHE_SIZE; | |
800 | } | |
801 | ||
802 | /* | |
803 | * Try to find an NFS request corresponding to this page | |
804 | * and update it. | |
805 | * If the existing request cannot be updated, we must flush | |
806 | * it out now. | |
807 | */ | |
808 | do { | |
809 | req = nfs_update_request(ctx, inode, page, offset, count); | |
810 | status = (IS_ERR(req)) ? PTR_ERR(req) : 0; | |
811 | if (status != -EBUSY) | |
812 | break; | |
813 | /* Request could not be updated. Flush it out and try again */ | |
814 | status = nfs_wb_page(inode, page); | |
815 | } while (status >= 0); | |
816 | if (status < 0) | |
817 | goto done; | |
818 | ||
819 | status = 0; | |
820 | ||
821 | /* Update file length */ | |
822 | nfs_grow_file(page, offset, count); | |
823 | /* Set the PG_uptodate flag? */ | |
824 | nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes); | |
825 | nfs_unlock_request(req); | |
826 | done: | |
827 | dprintk("NFS: nfs_updatepage returns %d (isize %Ld)\n", | |
828 | status, (long long)i_size_read(inode)); | |
829 | if (status < 0) | |
830 | ClearPageUptodate(page); | |
831 | return status; | |
832 | } | |
833 | ||
834 | static void nfs_writepage_release(struct nfs_page *req) | |
835 | { | |
836 | end_page_writeback(req->wb_page); | |
837 | ||
838 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
839 | if (!PageError(req->wb_page)) { | |
840 | if (NFS_NEED_RESCHED(req)) { | |
841 | nfs_mark_request_dirty(req); | |
842 | goto out; | |
843 | } else if (NFS_NEED_COMMIT(req)) { | |
844 | nfs_mark_request_commit(req); | |
845 | goto out; | |
846 | } | |
847 | } | |
848 | nfs_inode_remove_request(req); | |
849 | ||
850 | out: | |
851 | nfs_clear_commit(req); | |
852 | nfs_clear_reschedule(req); | |
853 | #else | |
854 | nfs_inode_remove_request(req); | |
855 | #endif | |
c6a556b8 | 856 | nfs_clear_page_writeback(req); |
1da177e4 LT |
857 | } |
858 | ||
859 | static inline int flush_task_priority(int how) | |
860 | { | |
861 | switch (how & (FLUSH_HIGHPRI|FLUSH_LOWPRI)) { | |
862 | case FLUSH_HIGHPRI: | |
863 | return RPC_PRIORITY_HIGH; | |
864 | case FLUSH_LOWPRI: | |
865 | return RPC_PRIORITY_LOW; | |
866 | } | |
867 | return RPC_PRIORITY_NORMAL; | |
868 | } | |
869 | ||
870 | /* | |
871 | * Set up the argument/result storage required for the RPC call. | |
872 | */ | |
873 | static void nfs_write_rpcsetup(struct nfs_page *req, | |
874 | struct nfs_write_data *data, | |
875 | unsigned int count, unsigned int offset, | |
876 | int how) | |
877 | { | |
1da177e4 LT |
878 | struct inode *inode; |
879 | ||
880 | /* Set up the RPC argument and reply structs | |
881 | * NB: take care not to mess about with data->commit et al. */ | |
882 | ||
883 | data->req = req; | |
884 | data->inode = inode = req->wb_context->dentry->d_inode; | |
885 | data->cred = req->wb_context->cred; | |
886 | ||
887 | data->args.fh = NFS_FH(inode); | |
888 | data->args.offset = req_offset(req) + offset; | |
889 | data->args.pgbase = req->wb_pgbase + offset; | |
890 | data->args.pages = data->pagevec; | |
891 | data->args.count = count; | |
892 | data->args.context = req->wb_context; | |
893 | ||
894 | data->res.fattr = &data->fattr; | |
895 | data->res.count = count; | |
896 | data->res.verf = &data->verf; | |
0e574af1 | 897 | nfs_fattr_init(&data->fattr); |
1da177e4 LT |
898 | |
899 | NFS_PROTO(inode)->write_setup(data, how); | |
900 | ||
901 | data->task.tk_priority = flush_task_priority(how); | |
902 | data->task.tk_cookie = (unsigned long)inode; | |
1da177e4 LT |
903 | |
904 | dprintk("NFS: %4d initiated write call (req %s/%Ld, %u bytes @ offset %Lu)\n", | |
0bbacc40 | 905 | data->task.tk_pid, |
1da177e4 LT |
906 | inode->i_sb->s_id, |
907 | (long long)NFS_FILEID(inode), | |
908 | count, | |
909 | (unsigned long long)data->args.offset); | |
910 | } | |
911 | ||
912 | static void nfs_execute_write(struct nfs_write_data *data) | |
913 | { | |
914 | struct rpc_clnt *clnt = NFS_CLIENT(data->inode); | |
915 | sigset_t oldset; | |
916 | ||
917 | rpc_clnt_sigmask(clnt, &oldset); | |
918 | lock_kernel(); | |
919 | rpc_execute(&data->task); | |
920 | unlock_kernel(); | |
921 | rpc_clnt_sigunmask(clnt, &oldset); | |
922 | } | |
923 | ||
924 | /* | |
925 | * Generate multiple small requests to write out a single | |
926 | * contiguous dirty area on one page. | |
927 | */ | |
928 | static int nfs_flush_multi(struct list_head *head, struct inode *inode, int how) | |
929 | { | |
930 | struct nfs_page *req = nfs_list_entry(head->next); | |
931 | struct page *page = req->wb_page; | |
932 | struct nfs_write_data *data; | |
933 | unsigned int wsize = NFS_SERVER(inode)->wsize; | |
934 | unsigned int nbytes, offset; | |
935 | int requests = 0; | |
936 | LIST_HEAD(list); | |
937 | ||
938 | nfs_list_remove_request(req); | |
939 | ||
940 | nbytes = req->wb_bytes; | |
941 | for (;;) { | |
40859d7e | 942 | data = nfs_writedata_alloc(1); |
1da177e4 LT |
943 | if (!data) |
944 | goto out_bad; | |
945 | list_add(&data->pages, &list); | |
946 | requests++; | |
947 | if (nbytes <= wsize) | |
948 | break; | |
949 | nbytes -= wsize; | |
950 | } | |
951 | atomic_set(&req->wb_complete, requests); | |
952 | ||
953 | ClearPageError(page); | |
bb713d6d | 954 | set_page_writeback(page); |
1da177e4 LT |
955 | offset = 0; |
956 | nbytes = req->wb_bytes; | |
957 | do { | |
958 | data = list_entry(list.next, struct nfs_write_data, pages); | |
959 | list_del_init(&data->pages); | |
960 | ||
961 | data->pagevec[0] = page; | |
962 | data->complete = nfs_writeback_done_partial; | |
963 | ||
964 | if (nbytes > wsize) { | |
965 | nfs_write_rpcsetup(req, data, wsize, offset, how); | |
966 | offset += wsize; | |
967 | nbytes -= wsize; | |
968 | } else { | |
969 | nfs_write_rpcsetup(req, data, nbytes, offset, how); | |
970 | nbytes = 0; | |
971 | } | |
972 | nfs_execute_write(data); | |
973 | } while (nbytes != 0); | |
974 | ||
975 | return 0; | |
976 | ||
977 | out_bad: | |
978 | while (!list_empty(&list)) { | |
979 | data = list_entry(list.next, struct nfs_write_data, pages); | |
980 | list_del(&data->pages); | |
981 | nfs_writedata_free(data); | |
982 | } | |
983 | nfs_mark_request_dirty(req); | |
c6a556b8 | 984 | nfs_clear_page_writeback(req); |
1da177e4 LT |
985 | return -ENOMEM; |
986 | } | |
987 | ||
988 | /* | |
989 | * Create an RPC task for the given write request and kick it. | |
990 | * The page must have been locked by the caller. | |
991 | * | |
992 | * It may happen that the page we're passed is not marked dirty. | |
993 | * This is the case if nfs_updatepage detects a conflicting request | |
994 | * that has been written but not committed. | |
995 | */ | |
996 | static int nfs_flush_one(struct list_head *head, struct inode *inode, int how) | |
997 | { | |
998 | struct nfs_page *req; | |
999 | struct page **pages; | |
1000 | struct nfs_write_data *data; | |
1001 | unsigned int count; | |
1002 | ||
1003 | if (NFS_SERVER(inode)->wsize < PAGE_CACHE_SIZE) | |
1004 | return nfs_flush_multi(head, inode, how); | |
1005 | ||
40859d7e | 1006 | data = nfs_writedata_alloc(NFS_SERVER(inode)->wpages); |
1da177e4 LT |
1007 | if (!data) |
1008 | goto out_bad; | |
1009 | ||
1010 | pages = data->pagevec; | |
1011 | count = 0; | |
1012 | while (!list_empty(head)) { | |
1013 | req = nfs_list_entry(head->next); | |
1014 | nfs_list_remove_request(req); | |
1015 | nfs_list_add_request(req, &data->pages); | |
1016 | ClearPageError(req->wb_page); | |
bb713d6d | 1017 | set_page_writeback(req->wb_page); |
1da177e4 LT |
1018 | *pages++ = req->wb_page; |
1019 | count += req->wb_bytes; | |
1020 | } | |
1021 | req = nfs_list_entry(data->pages.next); | |
1022 | ||
1023 | data->complete = nfs_writeback_done_full; | |
1024 | /* Set up the argument struct */ | |
1025 | nfs_write_rpcsetup(req, data, count, 0, how); | |
1026 | ||
1027 | nfs_execute_write(data); | |
1028 | return 0; | |
1029 | out_bad: | |
1030 | while (!list_empty(head)) { | |
1031 | struct nfs_page *req = nfs_list_entry(head->next); | |
1032 | nfs_list_remove_request(req); | |
1033 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1034 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1035 | } |
1036 | return -ENOMEM; | |
1037 | } | |
1038 | ||
1039 | static int | |
1040 | nfs_flush_list(struct list_head *head, int wpages, int how) | |
1041 | { | |
1042 | LIST_HEAD(one_request); | |
1043 | struct nfs_page *req; | |
1044 | int error = 0; | |
1045 | unsigned int pages = 0; | |
1046 | ||
1047 | while (!list_empty(head)) { | |
1048 | pages += nfs_coalesce_requests(head, &one_request, wpages); | |
1049 | req = nfs_list_entry(one_request.next); | |
1050 | error = nfs_flush_one(&one_request, req->wb_context->dentry->d_inode, how); | |
1051 | if (error < 0) | |
1052 | break; | |
1053 | } | |
1054 | if (error >= 0) | |
1055 | return pages; | |
1056 | ||
1057 | while (!list_empty(head)) { | |
1058 | req = nfs_list_entry(head->next); | |
1059 | nfs_list_remove_request(req); | |
1060 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1061 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1062 | } |
1063 | return error; | |
1064 | } | |
1065 | ||
1066 | /* | |
1067 | * Handle a write reply that flushed part of a page. | |
1068 | */ | |
1069 | static void nfs_writeback_done_partial(struct nfs_write_data *data, int status) | |
1070 | { | |
1071 | struct nfs_page *req = data->req; | |
1072 | struct page *page = req->wb_page; | |
1073 | ||
1074 | dprintk("NFS: write (%s/%Ld %d@%Ld)", | |
1075 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1076 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1077 | req->wb_bytes, | |
1078 | (long long)req_offset(req)); | |
1079 | ||
1080 | if (status < 0) { | |
1081 | ClearPageUptodate(page); | |
1082 | SetPageError(page); | |
1083 | req->wb_context->error = status; | |
1084 | dprintk(", error = %d\n", status); | |
1085 | } else { | |
1086 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1087 | if (data->verf.committed < NFS_FILE_SYNC) { | |
1088 | if (!NFS_NEED_COMMIT(req)) { | |
1089 | nfs_defer_commit(req); | |
1090 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1091 | dprintk(" defer commit\n"); | |
1092 | } else if (memcmp(&req->wb_verf, &data->verf, sizeof(req->wb_verf))) { | |
1093 | nfs_defer_reschedule(req); | |
1094 | dprintk(" server reboot detected\n"); | |
1095 | } | |
1096 | } else | |
1097 | #endif | |
1098 | dprintk(" OK\n"); | |
1099 | } | |
1100 | ||
1101 | if (atomic_dec_and_test(&req->wb_complete)) | |
1102 | nfs_writepage_release(req); | |
1103 | } | |
1104 | ||
1105 | /* | |
1106 | * Handle a write reply that flushes a whole page. | |
1107 | * | |
1108 | * FIXME: There is an inherent race with invalidate_inode_pages and | |
1109 | * writebacks since the page->count is kept > 1 for as long | |
1110 | * as the page has a write request pending. | |
1111 | */ | |
1112 | static void nfs_writeback_done_full(struct nfs_write_data *data, int status) | |
1113 | { | |
1114 | struct nfs_page *req; | |
1115 | struct page *page; | |
1116 | ||
1117 | /* Update attributes as result of writeback. */ | |
1118 | while (!list_empty(&data->pages)) { | |
1119 | req = nfs_list_entry(data->pages.next); | |
1120 | nfs_list_remove_request(req); | |
1121 | page = req->wb_page; | |
1122 | ||
1123 | dprintk("NFS: write (%s/%Ld %d@%Ld)", | |
1124 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1125 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1126 | req->wb_bytes, | |
1127 | (long long)req_offset(req)); | |
1128 | ||
1129 | if (status < 0) { | |
1130 | ClearPageUptodate(page); | |
1131 | SetPageError(page); | |
1132 | req->wb_context->error = status; | |
1133 | end_page_writeback(page); | |
1134 | nfs_inode_remove_request(req); | |
1135 | dprintk(", error = %d\n", status); | |
1136 | goto next; | |
1137 | } | |
1138 | end_page_writeback(page); | |
1139 | ||
1140 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1141 | if (data->args.stable != NFS_UNSTABLE || data->verf.committed == NFS_FILE_SYNC) { | |
1142 | nfs_inode_remove_request(req); | |
1143 | dprintk(" OK\n"); | |
1144 | goto next; | |
1145 | } | |
1146 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1147 | nfs_mark_request_commit(req); | |
1148 | dprintk(" marked for commit\n"); | |
1149 | #else | |
1150 | nfs_inode_remove_request(req); | |
1151 | #endif | |
1152 | next: | |
c6a556b8 | 1153 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1154 | } |
1155 | } | |
1156 | ||
1157 | /* | |
1158 | * This function is called when the WRITE call is complete. | |
1159 | */ | |
963d8fe5 | 1160 | void nfs_writeback_done(struct rpc_task *task, void *calldata) |
1da177e4 | 1161 | { |
963d8fe5 | 1162 | struct nfs_write_data *data = calldata; |
1da177e4 LT |
1163 | struct nfs_writeargs *argp = &data->args; |
1164 | struct nfs_writeres *resp = &data->res; | |
1165 | ||
1166 | dprintk("NFS: %4d nfs_writeback_done (status %d)\n", | |
1167 | task->tk_pid, task->tk_status); | |
1168 | ||
91d5b470 CL |
1169 | nfs_add_stats(data->inode, NFSIOS_SERVERWRITTENBYTES, resp->count); |
1170 | ||
1da177e4 LT |
1171 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) |
1172 | if (resp->verf->committed < argp->stable && task->tk_status >= 0) { | |
1173 | /* We tried a write call, but the server did not | |
1174 | * commit data to stable storage even though we | |
1175 | * requested it. | |
1176 | * Note: There is a known bug in Tru64 < 5.0 in which | |
1177 | * the server reports NFS_DATA_SYNC, but performs | |
1178 | * NFS_FILE_SYNC. We therefore implement this checking | |
1179 | * as a dprintk() in order to avoid filling syslog. | |
1180 | */ | |
1181 | static unsigned long complain; | |
1182 | ||
1183 | if (time_before(complain, jiffies)) { | |
1184 | dprintk("NFS: faulty NFS server %s:" | |
1185 | " (committed = %d) != (stable = %d)\n", | |
1186 | NFS_SERVER(data->inode)->hostname, | |
1187 | resp->verf->committed, argp->stable); | |
1188 | complain = jiffies + 300 * HZ; | |
1189 | } | |
1190 | } | |
1191 | #endif | |
1192 | /* Is this a short write? */ | |
1193 | if (task->tk_status >= 0 && resp->count < argp->count) { | |
1194 | static unsigned long complain; | |
1195 | ||
91d5b470 CL |
1196 | nfs_inc_stats(data->inode, NFSIOS_SHORTWRITE); |
1197 | ||
1da177e4 LT |
1198 | /* Has the server at least made some progress? */ |
1199 | if (resp->count != 0) { | |
1200 | /* Was this an NFSv2 write or an NFSv3 stable write? */ | |
1201 | if (resp->verf->committed != NFS_UNSTABLE) { | |
1202 | /* Resend from where the server left off */ | |
1203 | argp->offset += resp->count; | |
1204 | argp->pgbase += resp->count; | |
1205 | argp->count -= resp->count; | |
1206 | } else { | |
1207 | /* Resend as a stable write in order to avoid | |
1208 | * headaches in the case of a server crash. | |
1209 | */ | |
1210 | argp->stable = NFS_FILE_SYNC; | |
1211 | } | |
1212 | rpc_restart_call(task); | |
1213 | return; | |
1214 | } | |
1215 | if (time_before(complain, jiffies)) { | |
1216 | printk(KERN_WARNING | |
1217 | "NFS: Server wrote zero bytes, expected %u.\n", | |
1218 | argp->count); | |
1219 | complain = jiffies + 300 * HZ; | |
1220 | } | |
1221 | /* Can't do anything about it except throw an error. */ | |
1222 | task->tk_status = -EIO; | |
1223 | } | |
1224 | ||
1225 | /* | |
1226 | * Process the nfs_page list | |
1227 | */ | |
1228 | data->complete(data, task->tk_status); | |
1229 | } | |
1230 | ||
1231 | ||
1232 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
963d8fe5 | 1233 | void nfs_commit_release(void *wdata) |
1da177e4 | 1234 | { |
1da177e4 LT |
1235 | nfs_commit_free(wdata); |
1236 | } | |
1237 | ||
1238 | /* | |
1239 | * Set up the argument/result storage required for the RPC call. | |
1240 | */ | |
1241 | static void nfs_commit_rpcsetup(struct list_head *head, | |
1242 | struct nfs_write_data *data, int how) | |
1243 | { | |
3da28eb1 | 1244 | struct nfs_page *first; |
1da177e4 | 1245 | struct inode *inode; |
1da177e4 LT |
1246 | |
1247 | /* Set up the RPC argument and reply structs | |
1248 | * NB: take care not to mess about with data->commit et al. */ | |
1249 | ||
1250 | list_splice_init(head, &data->pages); | |
1251 | first = nfs_list_entry(data->pages.next); | |
1da177e4 LT |
1252 | inode = first->wb_context->dentry->d_inode; |
1253 | ||
1da177e4 LT |
1254 | data->inode = inode; |
1255 | data->cred = first->wb_context->cred; | |
1256 | ||
1257 | data->args.fh = NFS_FH(data->inode); | |
3da28eb1 TM |
1258 | /* Note: we always request a commit of the entire inode */ |
1259 | data->args.offset = 0; | |
1260 | data->args.count = 0; | |
1261 | data->res.count = 0; | |
1da177e4 LT |
1262 | data->res.fattr = &data->fattr; |
1263 | data->res.verf = &data->verf; | |
0e574af1 | 1264 | nfs_fattr_init(&data->fattr); |
1da177e4 LT |
1265 | |
1266 | NFS_PROTO(inode)->commit_setup(data, how); | |
1267 | ||
1268 | data->task.tk_priority = flush_task_priority(how); | |
1269 | data->task.tk_cookie = (unsigned long)inode; | |
1da177e4 | 1270 | |
0bbacc40 | 1271 | dprintk("NFS: %4d initiated commit call\n", data->task.tk_pid); |
1da177e4 LT |
1272 | } |
1273 | ||
1274 | /* | |
1275 | * Commit dirty pages | |
1276 | */ | |
1277 | static int | |
40859d7e | 1278 | nfs_commit_list(struct inode *inode, struct list_head *head, int how) |
1da177e4 LT |
1279 | { |
1280 | struct nfs_write_data *data; | |
1281 | struct nfs_page *req; | |
1282 | ||
40859d7e | 1283 | data = nfs_commit_alloc(NFS_SERVER(inode)->wpages); |
1da177e4 LT |
1284 | |
1285 | if (!data) | |
1286 | goto out_bad; | |
1287 | ||
1288 | /* Set up the argument struct */ | |
1289 | nfs_commit_rpcsetup(head, data, how); | |
1290 | ||
1291 | nfs_execute_write(data); | |
1292 | return 0; | |
1293 | out_bad: | |
1294 | while (!list_empty(head)) { | |
1295 | req = nfs_list_entry(head->next); | |
1296 | nfs_list_remove_request(req); | |
1297 | nfs_mark_request_commit(req); | |
c6a556b8 | 1298 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1299 | } |
1300 | return -ENOMEM; | |
1301 | } | |
1302 | ||
1303 | /* | |
1304 | * COMMIT call returned | |
1305 | */ | |
963d8fe5 | 1306 | void nfs_commit_done(struct rpc_task *task, void *calldata) |
1da177e4 | 1307 | { |
963d8fe5 | 1308 | struct nfs_write_data *data = calldata; |
1da177e4 LT |
1309 | struct nfs_page *req; |
1310 | int res = 0; | |
1311 | ||
1312 | dprintk("NFS: %4d nfs_commit_done (status %d)\n", | |
1313 | task->tk_pid, task->tk_status); | |
1314 | ||
1315 | while (!list_empty(&data->pages)) { | |
1316 | req = nfs_list_entry(data->pages.next); | |
1317 | nfs_list_remove_request(req); | |
1318 | ||
1319 | dprintk("NFS: commit (%s/%Ld %d@%Ld)", | |
1320 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1321 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1322 | req->wb_bytes, | |
1323 | (long long)req_offset(req)); | |
1324 | if (task->tk_status < 0) { | |
1325 | req->wb_context->error = task->tk_status; | |
1326 | nfs_inode_remove_request(req); | |
1327 | dprintk(", error = %d\n", task->tk_status); | |
1328 | goto next; | |
1329 | } | |
1330 | ||
1331 | /* Okay, COMMIT succeeded, apparently. Check the verifier | |
1332 | * returned by the server against all stored verfs. */ | |
1333 | if (!memcmp(req->wb_verf.verifier, data->verf.verifier, sizeof(data->verf.verifier))) { | |
1334 | /* We have a match */ | |
1335 | nfs_inode_remove_request(req); | |
1336 | dprintk(" OK\n"); | |
1337 | goto next; | |
1338 | } | |
1339 | /* We have a mismatch. Write the page again */ | |
1340 | dprintk(" mismatch\n"); | |
1341 | nfs_mark_request_dirty(req); | |
1342 | next: | |
c6a556b8 | 1343 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1344 | res++; |
1345 | } | |
1346 | sub_page_state(nr_unstable,res); | |
1347 | } | |
1348 | #endif | |
1349 | ||
1350 | static int nfs_flush_inode(struct inode *inode, unsigned long idx_start, | |
1351 | unsigned int npages, int how) | |
1352 | { | |
1353 | struct nfs_inode *nfsi = NFS_I(inode); | |
1354 | LIST_HEAD(head); | |
1355 | int res, | |
1356 | error = 0; | |
1357 | ||
1358 | spin_lock(&nfsi->req_lock); | |
1359 | res = nfs_scan_dirty(inode, &head, idx_start, npages); | |
1360 | spin_unlock(&nfsi->req_lock); | |
ab0a3dbe TM |
1361 | if (res) { |
1362 | struct nfs_server *server = NFS_SERVER(inode); | |
1363 | ||
1364 | /* For single writes, FLUSH_STABLE is more efficient */ | |
1365 | if (res == nfsi->npages && nfsi->npages <= server->wpages) { | |
1366 | if (res > 1 || nfs_list_entry(head.next)->wb_bytes <= server->wsize) | |
1367 | how |= FLUSH_STABLE; | |
1368 | } | |
1369 | error = nfs_flush_list(&head, server->wpages, how); | |
1370 | } | |
1da177e4 LT |
1371 | if (error < 0) |
1372 | return error; | |
1373 | return res; | |
1374 | } | |
1375 | ||
1376 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
3da28eb1 | 1377 | int nfs_commit_inode(struct inode *inode, int how) |
1da177e4 LT |
1378 | { |
1379 | struct nfs_inode *nfsi = NFS_I(inode); | |
1380 | LIST_HEAD(head); | |
1381 | int res, | |
1382 | error = 0; | |
1383 | ||
1384 | spin_lock(&nfsi->req_lock); | |
3da28eb1 TM |
1385 | res = nfs_scan_commit(inode, &head, 0, 0); |
1386 | spin_unlock(&nfsi->req_lock); | |
1da177e4 | 1387 | if (res) { |
40859d7e | 1388 | error = nfs_commit_list(inode, &head, how); |
3da28eb1 TM |
1389 | if (error < 0) |
1390 | return error; | |
1391 | } | |
1da177e4 LT |
1392 | return res; |
1393 | } | |
1394 | #endif | |
1395 | ||
1396 | int nfs_sync_inode(struct inode *inode, unsigned long idx_start, | |
1397 | unsigned int npages, int how) | |
1398 | { | |
70b9ecbd TM |
1399 | int nocommit = how & FLUSH_NOCOMMIT; |
1400 | int wait = how & FLUSH_WAIT; | |
1401 | int error; | |
1da177e4 | 1402 | |
70b9ecbd | 1403 | how &= ~(FLUSH_WAIT|FLUSH_NOCOMMIT); |
1da177e4 LT |
1404 | |
1405 | do { | |
70b9ecbd | 1406 | if (wait) { |
1da177e4 | 1407 | error = nfs_wait_on_requests(inode, idx_start, npages); |
70b9ecbd TM |
1408 | if (error != 0) |
1409 | continue; | |
1410 | } | |
1411 | error = nfs_flush_inode(inode, idx_start, npages, how); | |
1412 | if (error != 0) | |
1413 | continue; | |
1414 | if (!nocommit) | |
3da28eb1 | 1415 | error = nfs_commit_inode(inode, how); |
1da177e4 LT |
1416 | } while (error > 0); |
1417 | return error; | |
1418 | } | |
1419 | ||
1420 | int nfs_init_writepagecache(void) | |
1421 | { | |
1422 | nfs_wdata_cachep = kmem_cache_create("nfs_write_data", | |
1423 | sizeof(struct nfs_write_data), | |
1424 | 0, SLAB_HWCACHE_ALIGN, | |
1425 | NULL, NULL); | |
1426 | if (nfs_wdata_cachep == NULL) | |
1427 | return -ENOMEM; | |
1428 | ||
1429 | nfs_wdata_mempool = mempool_create(MIN_POOL_WRITE, | |
1430 | mempool_alloc_slab, | |
1431 | mempool_free_slab, | |
1432 | nfs_wdata_cachep); | |
1433 | if (nfs_wdata_mempool == NULL) | |
1434 | return -ENOMEM; | |
1435 | ||
1436 | nfs_commit_mempool = mempool_create(MIN_POOL_COMMIT, | |
1437 | mempool_alloc_slab, | |
1438 | mempool_free_slab, | |
1439 | nfs_wdata_cachep); | |
1440 | if (nfs_commit_mempool == NULL) | |
1441 | return -ENOMEM; | |
1442 | ||
1443 | return 0; | |
1444 | } | |
1445 | ||
1446 | void nfs_destroy_writepagecache(void) | |
1447 | { | |
1448 | mempool_destroy(nfs_commit_mempool); | |
1449 | mempool_destroy(nfs_wdata_mempool); | |
1450 | if (kmem_cache_destroy(nfs_wdata_cachep)) | |
1451 | printk(KERN_INFO "nfs_write_data: not all structures were freed\n"); | |
1452 | } | |
1453 |