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); | |
1da177e4 LT |
80 | static int nfs_wait_on_write_congestion(struct address_space *, int); |
81 | static int nfs_wait_on_requests(struct inode *, unsigned long, unsigned int); | |
82 | static int nfs_flush_inode(struct inode *inode, unsigned long idx_start, | |
83 | unsigned int npages, int how); | |
788e7a89 TM |
84 | static const struct rpc_call_ops nfs_write_partial_ops; |
85 | static const struct rpc_call_ops nfs_write_full_ops; | |
86 | static const struct rpc_call_ops nfs_commit_ops; | |
1da177e4 LT |
87 | |
88 | static kmem_cache_t *nfs_wdata_cachep; | |
3feb2d49 | 89 | static mempool_t *nfs_wdata_mempool; |
1da177e4 LT |
90 | static mempool_t *nfs_commit_mempool; |
91 | ||
92 | static DECLARE_WAIT_QUEUE_HEAD(nfs_write_congestion); | |
93 | ||
e17b1fc4 | 94 | struct nfs_write_data *nfs_commit_alloc(unsigned int pagecount) |
1da177e4 LT |
95 | { |
96 | struct nfs_write_data *p = mempool_alloc(nfs_commit_mempool, SLAB_NOFS); | |
40859d7e | 97 | |
1da177e4 LT |
98 | if (p) { |
99 | memset(p, 0, sizeof(*p)); | |
100 | INIT_LIST_HEAD(&p->pages); | |
40859d7e CL |
101 | if (pagecount < NFS_PAGEVEC_SIZE) |
102 | p->pagevec = &p->page_array[0]; | |
103 | else { | |
104 | size_t size = ++pagecount * sizeof(struct page *); | |
bd647545 ES |
105 | p->pagevec = kzalloc(size, GFP_NOFS); |
106 | if (!p->pagevec) { | |
40859d7e CL |
107 | mempool_free(p, nfs_commit_mempool); |
108 | p = NULL; | |
109 | } | |
110 | } | |
1da177e4 LT |
111 | } |
112 | return p; | |
113 | } | |
114 | ||
e17b1fc4 | 115 | void nfs_commit_free(struct nfs_write_data *p) |
1da177e4 | 116 | { |
40859d7e CL |
117 | if (p && (p->pagevec != &p->page_array[0])) |
118 | kfree(p->pagevec); | |
1da177e4 LT |
119 | mempool_free(p, nfs_commit_mempool); |
120 | } | |
121 | ||
3feb2d49 TM |
122 | struct nfs_write_data *nfs_writedata_alloc(unsigned int pagecount) |
123 | { | |
124 | struct nfs_write_data *p = mempool_alloc(nfs_wdata_mempool, SLAB_NOFS); | |
125 | ||
126 | if (p) { | |
127 | memset(p, 0, sizeof(*p)); | |
128 | INIT_LIST_HEAD(&p->pages); | |
129 | if (pagecount < NFS_PAGEVEC_SIZE) | |
130 | p->pagevec = &p->page_array[0]; | |
131 | else { | |
132 | size_t size = ++pagecount * sizeof(struct page *); | |
133 | p->pagevec = kmalloc(size, GFP_NOFS); | |
134 | if (p->pagevec) { | |
135 | memset(p->pagevec, 0, size); | |
136 | } else { | |
137 | mempool_free(p, nfs_wdata_mempool); | |
138 | p = NULL; | |
139 | } | |
140 | } | |
141 | } | |
142 | return p; | |
143 | } | |
144 | ||
145 | void nfs_writedata_free(struct nfs_write_data *p) | |
146 | { | |
147 | if (p && (p->pagevec != &p->page_array[0])) | |
148 | kfree(p->pagevec); | |
149 | mempool_free(p, nfs_wdata_mempool); | |
150 | } | |
151 | ||
963d8fe5 | 152 | void nfs_writedata_release(void *wdata) |
1da177e4 | 153 | { |
1da177e4 LT |
154 | nfs_writedata_free(wdata); |
155 | } | |
156 | ||
157 | /* Adjust the file length if we're writing beyond the end */ | |
158 | static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count) | |
159 | { | |
160 | struct inode *inode = page->mapping->host; | |
161 | loff_t end, i_size = i_size_read(inode); | |
162 | unsigned long end_index = (i_size - 1) >> PAGE_CACHE_SHIFT; | |
163 | ||
164 | if (i_size > 0 && page->index < end_index) | |
165 | return; | |
166 | end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + ((loff_t)offset+count); | |
167 | if (i_size >= end) | |
168 | return; | |
91d5b470 | 169 | nfs_inc_stats(inode, NFSIOS_EXTENDWRITE); |
1da177e4 LT |
170 | i_size_write(inode, end); |
171 | } | |
172 | ||
173 | /* We can set the PG_uptodate flag if we see that a write request | |
174 | * covers the full page. | |
175 | */ | |
176 | static void nfs_mark_uptodate(struct page *page, unsigned int base, unsigned int count) | |
177 | { | |
178 | loff_t end_offs; | |
179 | ||
180 | if (PageUptodate(page)) | |
181 | return; | |
182 | if (base != 0) | |
183 | return; | |
184 | if (count == PAGE_CACHE_SIZE) { | |
185 | SetPageUptodate(page); | |
186 | return; | |
187 | } | |
188 | ||
189 | end_offs = i_size_read(page->mapping->host) - 1; | |
190 | if (end_offs < 0) | |
191 | return; | |
192 | /* Is this the last page? */ | |
193 | if (page->index != (unsigned long)(end_offs >> PAGE_CACHE_SHIFT)) | |
194 | return; | |
195 | /* This is the last page: set PG_uptodate if we cover the entire | |
196 | * extent of the data, then zero the rest of the page. | |
197 | */ | |
198 | if (count == (unsigned int)(end_offs & (PAGE_CACHE_SIZE - 1)) + 1) { | |
199 | memclear_highpage_flush(page, count, PAGE_CACHE_SIZE - count); | |
200 | SetPageUptodate(page); | |
201 | } | |
202 | } | |
203 | ||
204 | /* | |
205 | * Write a page synchronously. | |
206 | * Offset is the data offset within the page. | |
207 | */ | |
208 | static int nfs_writepage_sync(struct nfs_open_context *ctx, struct inode *inode, | |
209 | struct page *page, unsigned int offset, unsigned int count, | |
210 | int how) | |
211 | { | |
212 | unsigned int wsize = NFS_SERVER(inode)->wsize; | |
213 | int result, written = 0; | |
214 | struct nfs_write_data *wdata; | |
215 | ||
40859d7e | 216 | wdata = nfs_writedata_alloc(1); |
1da177e4 LT |
217 | if (!wdata) |
218 | return -ENOMEM; | |
219 | ||
220 | wdata->flags = how; | |
221 | wdata->cred = ctx->cred; | |
222 | wdata->inode = inode; | |
223 | wdata->args.fh = NFS_FH(inode); | |
224 | wdata->args.context = ctx; | |
225 | wdata->args.pages = &page; | |
226 | wdata->args.stable = NFS_FILE_SYNC; | |
227 | wdata->args.pgbase = offset; | |
228 | wdata->args.count = wsize; | |
229 | wdata->res.fattr = &wdata->fattr; | |
230 | wdata->res.verf = &wdata->verf; | |
231 | ||
232 | dprintk("NFS: nfs_writepage_sync(%s/%Ld %d@%Ld)\n", | |
233 | inode->i_sb->s_id, | |
234 | (long long)NFS_FILEID(inode), | |
235 | count, (long long)(page_offset(page) + offset)); | |
236 | ||
bb713d6d | 237 | set_page_writeback(page); |
1da177e4 LT |
238 | nfs_begin_data_update(inode); |
239 | do { | |
240 | if (count < wsize) | |
241 | wdata->args.count = count; | |
242 | wdata->args.offset = page_offset(page) + wdata->args.pgbase; | |
243 | ||
244 | result = NFS_PROTO(inode)->write(wdata); | |
245 | ||
246 | if (result < 0) { | |
247 | /* Must mark the page invalid after I/O error */ | |
248 | ClearPageUptodate(page); | |
249 | goto io_error; | |
250 | } | |
251 | if (result < wdata->args.count) | |
252 | printk(KERN_WARNING "NFS: short write, count=%u, result=%d\n", | |
253 | wdata->args.count, result); | |
254 | ||
255 | wdata->args.offset += result; | |
256 | wdata->args.pgbase += result; | |
257 | written += result; | |
258 | count -= result; | |
91d5b470 | 259 | nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, result); |
1da177e4 LT |
260 | } while (count); |
261 | /* Update file length */ | |
262 | nfs_grow_file(page, offset, written); | |
263 | /* Set the PG_uptodate flag? */ | |
264 | nfs_mark_uptodate(page, offset, written); | |
265 | ||
266 | if (PageError(page)) | |
267 | ClearPageError(page); | |
268 | ||
269 | io_error: | |
951a143b | 270 | nfs_end_data_update(inode); |
bb713d6d | 271 | end_page_writeback(page); |
1da177e4 LT |
272 | nfs_writedata_free(wdata); |
273 | return written ? written : result; | |
274 | } | |
275 | ||
276 | static int nfs_writepage_async(struct nfs_open_context *ctx, | |
277 | struct inode *inode, struct page *page, | |
278 | unsigned int offset, unsigned int count) | |
279 | { | |
280 | struct nfs_page *req; | |
1da177e4 LT |
281 | |
282 | req = nfs_update_request(ctx, inode, page, offset, count); | |
abd3e641 TM |
283 | if (IS_ERR(req)) |
284 | return PTR_ERR(req); | |
1da177e4 LT |
285 | /* Update file length */ |
286 | nfs_grow_file(page, offset, count); | |
287 | /* Set the PG_uptodate flag? */ | |
288 | nfs_mark_uptodate(page, offset, count); | |
289 | nfs_unlock_request(req); | |
abd3e641 | 290 | return 0; |
1da177e4 LT |
291 | } |
292 | ||
293 | static int wb_priority(struct writeback_control *wbc) | |
294 | { | |
295 | if (wbc->for_reclaim) | |
296 | return FLUSH_HIGHPRI; | |
297 | if (wbc->for_kupdate) | |
298 | return FLUSH_LOWPRI; | |
299 | return 0; | |
300 | } | |
301 | ||
302 | /* | |
303 | * Write an mmapped page to the server. | |
304 | */ | |
305 | int nfs_writepage(struct page *page, struct writeback_control *wbc) | |
306 | { | |
307 | struct nfs_open_context *ctx; | |
308 | struct inode *inode = page->mapping->host; | |
309 | unsigned long end_index; | |
310 | unsigned offset = PAGE_CACHE_SIZE; | |
311 | loff_t i_size = i_size_read(inode); | |
312 | int inode_referenced = 0; | |
313 | int priority = wb_priority(wbc); | |
314 | int err; | |
315 | ||
91d5b470 CL |
316 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); |
317 | nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1); | |
318 | ||
1da177e4 LT |
319 | /* |
320 | * Note: We need to ensure that we have a reference to the inode | |
321 | * if we are to do asynchronous writes. If not, waiting | |
322 | * in nfs_wait_on_request() may deadlock with clear_inode(). | |
323 | * | |
324 | * If igrab() fails here, then it is in any case safe to | |
325 | * call nfs_wb_page(), since there will be no pending writes. | |
326 | */ | |
327 | if (igrab(inode) != 0) | |
328 | inode_referenced = 1; | |
329 | end_index = i_size >> PAGE_CACHE_SHIFT; | |
330 | ||
331 | /* Ensure we've flushed out any previous writes */ | |
332 | nfs_wb_page_priority(inode, page, priority); | |
333 | ||
334 | /* easy case */ | |
335 | if (page->index < end_index) | |
336 | goto do_it; | |
337 | /* things got complicated... */ | |
338 | offset = i_size & (PAGE_CACHE_SIZE-1); | |
339 | ||
340 | /* OK, are we completely out? */ | |
341 | err = 0; /* potential race with truncate - ignore */ | |
342 | if (page->index >= end_index+1 || !offset) | |
343 | goto out; | |
344 | do_it: | |
d530838b | 345 | ctx = nfs_find_open_context(inode, NULL, FMODE_WRITE); |
1da177e4 LT |
346 | if (ctx == NULL) { |
347 | err = -EBADF; | |
348 | goto out; | |
349 | } | |
350 | lock_kernel(); | |
351 | if (!IS_SYNC(inode) && inode_referenced) { | |
352 | err = nfs_writepage_async(ctx, inode, page, 0, offset); | |
abd3e641 TM |
353 | if (!wbc->for_writepages) |
354 | nfs_flush_inode(inode, 0, 0, wb_priority(wbc)); | |
1da177e4 LT |
355 | } else { |
356 | err = nfs_writepage_sync(ctx, inode, page, 0, | |
357 | offset, priority); | |
358 | if (err >= 0) { | |
359 | if (err != offset) | |
360 | redirty_page_for_writepage(wbc, page); | |
361 | err = 0; | |
362 | } | |
363 | } | |
364 | unlock_kernel(); | |
365 | put_nfs_open_context(ctx); | |
366 | out: | |
367 | unlock_page(page); | |
368 | if (inode_referenced) | |
369 | iput(inode); | |
370 | return err; | |
371 | } | |
372 | ||
373 | /* | |
374 | * Note: causes nfs_update_request() to block on the assumption | |
375 | * that the writeback is generated due to memory pressure. | |
376 | */ | |
377 | int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) | |
378 | { | |
379 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
380 | struct inode *inode = mapping->host; | |
381 | int err; | |
382 | ||
91d5b470 CL |
383 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); |
384 | ||
1da177e4 LT |
385 | err = generic_writepages(mapping, wbc); |
386 | if (err) | |
387 | return err; | |
388 | while (test_and_set_bit(BDI_write_congested, &bdi->state) != 0) { | |
389 | if (wbc->nonblocking) | |
390 | return 0; | |
391 | nfs_wait_on_write_congestion(mapping, 0); | |
392 | } | |
393 | err = nfs_flush_inode(inode, 0, 0, wb_priority(wbc)); | |
394 | if (err < 0) | |
395 | goto out; | |
91d5b470 | 396 | nfs_add_stats(inode, NFSIOS_WRITEPAGES, err); |
1da177e4 LT |
397 | wbc->nr_to_write -= err; |
398 | if (!wbc->nonblocking && wbc->sync_mode == WB_SYNC_ALL) { | |
399 | err = nfs_wait_on_requests(inode, 0, 0); | |
400 | if (err < 0) | |
401 | goto out; | |
402 | } | |
3da28eb1 | 403 | err = nfs_commit_inode(inode, wb_priority(wbc)); |
1da177e4 LT |
404 | if (err > 0) { |
405 | wbc->nr_to_write -= err; | |
406 | err = 0; | |
407 | } | |
408 | out: | |
409 | clear_bit(BDI_write_congested, &bdi->state); | |
410 | wake_up_all(&nfs_write_congestion); | |
411 | return err; | |
412 | } | |
413 | ||
414 | /* | |
415 | * Insert a write request into an inode | |
416 | */ | |
417 | static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req) | |
418 | { | |
419 | struct nfs_inode *nfsi = NFS_I(inode); | |
420 | int error; | |
421 | ||
422 | error = radix_tree_insert(&nfsi->nfs_page_tree, req->wb_index, req); | |
423 | BUG_ON(error == -EEXIST); | |
424 | if (error) | |
425 | return error; | |
426 | if (!nfsi->npages) { | |
427 | igrab(inode); | |
428 | nfs_begin_data_update(inode); | |
429 | if (nfs_have_delegation(inode, FMODE_WRITE)) | |
430 | nfsi->change_attr++; | |
431 | } | |
deb7d638 | 432 | SetPagePrivate(req->wb_page); |
1da177e4 LT |
433 | nfsi->npages++; |
434 | atomic_inc(&req->wb_count); | |
435 | return 0; | |
436 | } | |
437 | ||
438 | /* | |
439 | * Insert a write request into an inode | |
440 | */ | |
441 | static void nfs_inode_remove_request(struct nfs_page *req) | |
442 | { | |
443 | struct inode *inode = req->wb_context->dentry->d_inode; | |
444 | struct nfs_inode *nfsi = NFS_I(inode); | |
445 | ||
446 | BUG_ON (!NFS_WBACK_BUSY(req)); | |
447 | ||
448 | spin_lock(&nfsi->req_lock); | |
deb7d638 | 449 | ClearPagePrivate(req->wb_page); |
1da177e4 LT |
450 | radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index); |
451 | nfsi->npages--; | |
452 | if (!nfsi->npages) { | |
453 | spin_unlock(&nfsi->req_lock); | |
951a143b | 454 | nfs_end_data_update(inode); |
1da177e4 LT |
455 | iput(inode); |
456 | } else | |
457 | spin_unlock(&nfsi->req_lock); | |
458 | nfs_clear_request(req); | |
459 | nfs_release_request(req); | |
460 | } | |
461 | ||
462 | /* | |
463 | * Find a request | |
464 | */ | |
465 | static inline struct nfs_page * | |
466 | _nfs_find_request(struct inode *inode, unsigned long index) | |
467 | { | |
468 | struct nfs_inode *nfsi = NFS_I(inode); | |
469 | struct nfs_page *req; | |
470 | ||
471 | req = (struct nfs_page*)radix_tree_lookup(&nfsi->nfs_page_tree, index); | |
472 | if (req) | |
473 | atomic_inc(&req->wb_count); | |
474 | return req; | |
475 | } | |
476 | ||
477 | static struct nfs_page * | |
478 | nfs_find_request(struct inode *inode, unsigned long index) | |
479 | { | |
480 | struct nfs_page *req; | |
481 | struct nfs_inode *nfsi = NFS_I(inode); | |
482 | ||
483 | spin_lock(&nfsi->req_lock); | |
484 | req = _nfs_find_request(inode, index); | |
485 | spin_unlock(&nfsi->req_lock); | |
486 | return req; | |
487 | } | |
488 | ||
489 | /* | |
490 | * Add a request to the inode's dirty list. | |
491 | */ | |
492 | static void | |
493 | nfs_mark_request_dirty(struct nfs_page *req) | |
494 | { | |
495 | struct inode *inode = req->wb_context->dentry->d_inode; | |
496 | struct nfs_inode *nfsi = NFS_I(inode); | |
497 | ||
498 | spin_lock(&nfsi->req_lock); | |
3da28eb1 TM |
499 | radix_tree_tag_set(&nfsi->nfs_page_tree, |
500 | req->wb_index, NFS_PAGE_TAG_DIRTY); | |
1da177e4 LT |
501 | nfs_list_add_request(req, &nfsi->dirty); |
502 | nfsi->ndirty++; | |
503 | spin_unlock(&nfsi->req_lock); | |
504 | inc_page_state(nr_dirty); | |
505 | mark_inode_dirty(inode); | |
506 | } | |
507 | ||
508 | /* | |
509 | * Check if a request is dirty | |
510 | */ | |
511 | static inline int | |
512 | nfs_dirty_request(struct nfs_page *req) | |
513 | { | |
514 | struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode); | |
515 | return !list_empty(&req->wb_list) && req->wb_list_head == &nfsi->dirty; | |
516 | } | |
517 | ||
518 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
519 | /* | |
520 | * Add a request to the inode's commit list. | |
521 | */ | |
522 | static void | |
523 | nfs_mark_request_commit(struct nfs_page *req) | |
524 | { | |
525 | struct inode *inode = req->wb_context->dentry->d_inode; | |
526 | struct nfs_inode *nfsi = NFS_I(inode); | |
527 | ||
528 | spin_lock(&nfsi->req_lock); | |
529 | nfs_list_add_request(req, &nfsi->commit); | |
530 | nfsi->ncommit++; | |
531 | spin_unlock(&nfsi->req_lock); | |
532 | inc_page_state(nr_unstable); | |
533 | mark_inode_dirty(inode); | |
534 | } | |
535 | #endif | |
536 | ||
537 | /* | |
538 | * Wait for a request to complete. | |
539 | * | |
540 | * Interruptible by signals only if mounted with intr flag. | |
541 | */ | |
c42de9dd | 542 | static int nfs_wait_on_requests_locked(struct inode *inode, unsigned long idx_start, unsigned int npages) |
1da177e4 LT |
543 | { |
544 | struct nfs_inode *nfsi = NFS_I(inode); | |
545 | struct nfs_page *req; | |
546 | unsigned long idx_end, next; | |
547 | unsigned int res = 0; | |
548 | int error; | |
549 | ||
550 | if (npages == 0) | |
551 | idx_end = ~0; | |
552 | else | |
553 | idx_end = idx_start + npages - 1; | |
554 | ||
1da177e4 | 555 | next = idx_start; |
c6a556b8 | 556 | while (radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree, (void **)&req, next, 1, NFS_PAGE_TAG_WRITEBACK)) { |
1da177e4 LT |
557 | if (req->wb_index > idx_end) |
558 | break; | |
559 | ||
560 | next = req->wb_index + 1; | |
c6a556b8 | 561 | BUG_ON(!NFS_WBACK_BUSY(req)); |
1da177e4 LT |
562 | |
563 | atomic_inc(&req->wb_count); | |
564 | spin_unlock(&nfsi->req_lock); | |
565 | error = nfs_wait_on_request(req); | |
566 | nfs_release_request(req); | |
c42de9dd | 567 | spin_lock(&nfsi->req_lock); |
1da177e4 LT |
568 | if (error < 0) |
569 | return error; | |
1da177e4 LT |
570 | res++; |
571 | } | |
1da177e4 LT |
572 | return res; |
573 | } | |
574 | ||
c42de9dd TM |
575 | static int nfs_wait_on_requests(struct inode *inode, unsigned long idx_start, unsigned int npages) |
576 | { | |
577 | struct nfs_inode *nfsi = NFS_I(inode); | |
578 | int ret; | |
579 | ||
580 | spin_lock(&nfsi->req_lock); | |
581 | ret = nfs_wait_on_requests_locked(inode, idx_start, npages); | |
582 | spin_unlock(&nfsi->req_lock); | |
583 | return ret; | |
584 | } | |
585 | ||
1da177e4 LT |
586 | /* |
587 | * nfs_scan_dirty - Scan an inode for dirty requests | |
588 | * @inode: NFS inode to scan | |
589 | * @dst: destination list | |
590 | * @idx_start: lower bound of page->index to scan. | |
591 | * @npages: idx_start + npages sets the upper bound to scan. | |
592 | * | |
593 | * Moves requests from the inode's dirty page list. | |
594 | * The requests are *not* checked to ensure that they form a contiguous set. | |
595 | */ | |
596 | static int | |
597 | nfs_scan_dirty(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
598 | { | |
599 | struct nfs_inode *nfsi = NFS_I(inode); | |
3da28eb1 TM |
600 | int res = 0; |
601 | ||
602 | if (nfsi->ndirty != 0) { | |
603 | res = nfs_scan_lock_dirty(nfsi, dst, idx_start, npages); | |
604 | nfsi->ndirty -= res; | |
605 | sub_page_state(nr_dirty,res); | |
606 | if ((nfsi->ndirty == 0) != list_empty(&nfsi->dirty)) | |
607 | printk(KERN_ERR "NFS: desynchronized value of nfs_i.ndirty.\n"); | |
608 | } | |
1da177e4 LT |
609 | return res; |
610 | } | |
611 | ||
612 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
613 | /* | |
614 | * nfs_scan_commit - Scan an inode for commit requests | |
615 | * @inode: NFS inode to scan | |
616 | * @dst: destination list | |
617 | * @idx_start: lower bound of page->index to scan. | |
618 | * @npages: idx_start + npages sets the upper bound to scan. | |
619 | * | |
620 | * Moves requests from the inode's 'commit' request list. | |
621 | * The requests are *not* checked to ensure that they form a contiguous set. | |
622 | */ | |
623 | static int | |
624 | nfs_scan_commit(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
625 | { | |
626 | struct nfs_inode *nfsi = NFS_I(inode); | |
3da28eb1 TM |
627 | int res = 0; |
628 | ||
629 | if (nfsi->ncommit != 0) { | |
630 | res = nfs_scan_list(&nfsi->commit, dst, idx_start, npages); | |
631 | nfsi->ncommit -= res; | |
632 | if ((nfsi->ncommit == 0) != list_empty(&nfsi->commit)) | |
633 | printk(KERN_ERR "NFS: desynchronized value of nfs_i.ncommit.\n"); | |
634 | } | |
1da177e4 LT |
635 | return res; |
636 | } | |
c42de9dd TM |
637 | #else |
638 | static inline int nfs_scan_commit(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
639 | { | |
640 | return 0; | |
641 | } | |
1da177e4 LT |
642 | #endif |
643 | ||
644 | static int nfs_wait_on_write_congestion(struct address_space *mapping, int intr) | |
645 | { | |
646 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
647 | DEFINE_WAIT(wait); | |
648 | int ret = 0; | |
649 | ||
650 | might_sleep(); | |
651 | ||
652 | if (!bdi_write_congested(bdi)) | |
653 | return 0; | |
91d5b470 CL |
654 | |
655 | nfs_inc_stats(mapping->host, NFSIOS_CONGESTIONWAIT); | |
656 | ||
1da177e4 LT |
657 | if (intr) { |
658 | struct rpc_clnt *clnt = NFS_CLIENT(mapping->host); | |
659 | sigset_t oldset; | |
660 | ||
661 | rpc_clnt_sigmask(clnt, &oldset); | |
662 | prepare_to_wait(&nfs_write_congestion, &wait, TASK_INTERRUPTIBLE); | |
663 | if (bdi_write_congested(bdi)) { | |
664 | if (signalled()) | |
665 | ret = -ERESTARTSYS; | |
666 | else | |
667 | schedule(); | |
668 | } | |
669 | rpc_clnt_sigunmask(clnt, &oldset); | |
670 | } else { | |
671 | prepare_to_wait(&nfs_write_congestion, &wait, TASK_UNINTERRUPTIBLE); | |
672 | if (bdi_write_congested(bdi)) | |
673 | schedule(); | |
674 | } | |
675 | finish_wait(&nfs_write_congestion, &wait); | |
676 | return ret; | |
677 | } | |
678 | ||
679 | ||
680 | /* | |
681 | * Try to update any existing write request, or create one if there is none. | |
682 | * In order to match, the request's credentials must match those of | |
683 | * the calling process. | |
684 | * | |
685 | * Note: Should always be called with the Page Lock held! | |
686 | */ | |
687 | static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx, | |
688 | struct inode *inode, struct page *page, | |
689 | unsigned int offset, unsigned int bytes) | |
690 | { | |
691 | struct nfs_server *server = NFS_SERVER(inode); | |
692 | struct nfs_inode *nfsi = NFS_I(inode); | |
693 | struct nfs_page *req, *new = NULL; | |
694 | unsigned long rqend, end; | |
695 | ||
696 | end = offset + bytes; | |
697 | ||
698 | if (nfs_wait_on_write_congestion(page->mapping, server->flags & NFS_MOUNT_INTR)) | |
699 | return ERR_PTR(-ERESTARTSYS); | |
700 | for (;;) { | |
701 | /* Loop over all inode entries and see if we find | |
702 | * A request for the page we wish to update | |
703 | */ | |
704 | spin_lock(&nfsi->req_lock); | |
705 | req = _nfs_find_request(inode, page->index); | |
706 | if (req) { | |
707 | if (!nfs_lock_request_dontget(req)) { | |
708 | int error; | |
709 | spin_unlock(&nfsi->req_lock); | |
710 | error = nfs_wait_on_request(req); | |
711 | nfs_release_request(req); | |
1dd594b2 NB |
712 | if (error < 0) { |
713 | if (new) | |
714 | nfs_release_request(new); | |
1da177e4 | 715 | return ERR_PTR(error); |
1dd594b2 | 716 | } |
1da177e4 LT |
717 | continue; |
718 | } | |
719 | spin_unlock(&nfsi->req_lock); | |
720 | if (new) | |
721 | nfs_release_request(new); | |
722 | break; | |
723 | } | |
724 | ||
725 | if (new) { | |
726 | int error; | |
727 | nfs_lock_request_dontget(new); | |
728 | error = nfs_inode_add_request(inode, new); | |
729 | if (error) { | |
730 | spin_unlock(&nfsi->req_lock); | |
731 | nfs_unlock_request(new); | |
732 | return ERR_PTR(error); | |
733 | } | |
734 | spin_unlock(&nfsi->req_lock); | |
735 | nfs_mark_request_dirty(new); | |
736 | return new; | |
737 | } | |
738 | spin_unlock(&nfsi->req_lock); | |
739 | ||
740 | new = nfs_create_request(ctx, inode, page, offset, bytes); | |
741 | if (IS_ERR(new)) | |
742 | return new; | |
743 | } | |
744 | ||
745 | /* We have a request for our page. | |
746 | * If the creds don't match, or the | |
747 | * page addresses don't match, | |
748 | * tell the caller to wait on the conflicting | |
749 | * request. | |
750 | */ | |
751 | rqend = req->wb_offset + req->wb_bytes; | |
752 | if (req->wb_context != ctx | |
753 | || req->wb_page != page | |
754 | || !nfs_dirty_request(req) | |
755 | || offset > rqend || end < req->wb_offset) { | |
756 | nfs_unlock_request(req); | |
757 | return ERR_PTR(-EBUSY); | |
758 | } | |
759 | ||
760 | /* Okay, the request matches. Update the region */ | |
761 | if (offset < req->wb_offset) { | |
762 | req->wb_offset = offset; | |
763 | req->wb_pgbase = offset; | |
764 | req->wb_bytes = rqend - req->wb_offset; | |
765 | } | |
766 | ||
767 | if (end > rqend) | |
768 | req->wb_bytes = end - req->wb_offset; | |
769 | ||
770 | return req; | |
771 | } | |
772 | ||
773 | int nfs_flush_incompatible(struct file *file, struct page *page) | |
774 | { | |
775 | struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data; | |
776 | struct inode *inode = page->mapping->host; | |
777 | struct nfs_page *req; | |
778 | int status = 0; | |
779 | /* | |
780 | * Look for a request corresponding to this page. If there | |
781 | * is one, and it belongs to another file, we flush it out | |
782 | * before we try to copy anything into the page. Do this | |
783 | * due to the lack of an ACCESS-type call in NFSv2. | |
784 | * Also do the same if we find a request from an existing | |
785 | * dropped page. | |
786 | */ | |
787 | req = nfs_find_request(inode, page->index); | |
788 | if (req) { | |
789 | if (req->wb_page != page || ctx != req->wb_context) | |
790 | status = nfs_wb_page(inode, page); | |
791 | nfs_release_request(req); | |
792 | } | |
793 | return (status < 0) ? status : 0; | |
794 | } | |
795 | ||
796 | /* | |
797 | * Update and possibly write a cached page of an NFS file. | |
798 | * | |
799 | * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad | |
800 | * things with a page scheduled for an RPC call (e.g. invalidate it). | |
801 | */ | |
802 | int nfs_updatepage(struct file *file, struct page *page, | |
803 | unsigned int offset, unsigned int count) | |
804 | { | |
805 | struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data; | |
1da177e4 LT |
806 | struct inode *inode = page->mapping->host; |
807 | struct nfs_page *req; | |
808 | int status = 0; | |
809 | ||
91d5b470 CL |
810 | nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE); |
811 | ||
1da177e4 | 812 | dprintk("NFS: nfs_updatepage(%s/%s %d@%Ld)\n", |
0bbacc40 CL |
813 | file->f_dentry->d_parent->d_name.name, |
814 | file->f_dentry->d_name.name, count, | |
815 | (long long)(page_offset(page) +offset)); | |
1da177e4 LT |
816 | |
817 | if (IS_SYNC(inode)) { | |
818 | status = nfs_writepage_sync(ctx, inode, page, offset, count, 0); | |
819 | if (status > 0) { | |
820 | if (offset == 0 && status == PAGE_CACHE_SIZE) | |
821 | SetPageUptodate(page); | |
822 | return 0; | |
823 | } | |
824 | return status; | |
825 | } | |
826 | ||
827 | /* If we're not using byte range locks, and we know the page | |
828 | * is entirely in cache, it may be more efficient to avoid | |
829 | * fragmenting write requests. | |
830 | */ | |
ab0a3dbe | 831 | if (PageUptodate(page) && inode->i_flock == NULL && !(file->f_mode & O_SYNC)) { |
1da177e4 LT |
832 | loff_t end_offs = i_size_read(inode) - 1; |
833 | unsigned long end_index = end_offs >> PAGE_CACHE_SHIFT; | |
834 | ||
835 | count += offset; | |
836 | offset = 0; | |
837 | if (unlikely(end_offs < 0)) { | |
838 | /* Do nothing */ | |
839 | } else if (page->index == end_index) { | |
840 | unsigned int pglen; | |
841 | pglen = (unsigned int)(end_offs & (PAGE_CACHE_SIZE-1)) + 1; | |
842 | if (count < pglen) | |
843 | count = pglen; | |
844 | } else if (page->index < end_index) | |
845 | count = PAGE_CACHE_SIZE; | |
846 | } | |
847 | ||
848 | /* | |
849 | * Try to find an NFS request corresponding to this page | |
850 | * and update it. | |
851 | * If the existing request cannot be updated, we must flush | |
852 | * it out now. | |
853 | */ | |
854 | do { | |
855 | req = nfs_update_request(ctx, inode, page, offset, count); | |
856 | status = (IS_ERR(req)) ? PTR_ERR(req) : 0; | |
857 | if (status != -EBUSY) | |
858 | break; | |
859 | /* Request could not be updated. Flush it out and try again */ | |
860 | status = nfs_wb_page(inode, page); | |
861 | } while (status >= 0); | |
862 | if (status < 0) | |
863 | goto done; | |
864 | ||
865 | status = 0; | |
866 | ||
867 | /* Update file length */ | |
868 | nfs_grow_file(page, offset, count); | |
869 | /* Set the PG_uptodate flag? */ | |
870 | nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes); | |
871 | nfs_unlock_request(req); | |
872 | done: | |
873 | dprintk("NFS: nfs_updatepage returns %d (isize %Ld)\n", | |
874 | status, (long long)i_size_read(inode)); | |
875 | if (status < 0) | |
876 | ClearPageUptodate(page); | |
877 | return status; | |
878 | } | |
879 | ||
880 | static void nfs_writepage_release(struct nfs_page *req) | |
881 | { | |
882 | end_page_writeback(req->wb_page); | |
883 | ||
884 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
885 | if (!PageError(req->wb_page)) { | |
886 | if (NFS_NEED_RESCHED(req)) { | |
887 | nfs_mark_request_dirty(req); | |
888 | goto out; | |
889 | } else if (NFS_NEED_COMMIT(req)) { | |
890 | nfs_mark_request_commit(req); | |
891 | goto out; | |
892 | } | |
893 | } | |
894 | nfs_inode_remove_request(req); | |
895 | ||
896 | out: | |
897 | nfs_clear_commit(req); | |
898 | nfs_clear_reschedule(req); | |
899 | #else | |
900 | nfs_inode_remove_request(req); | |
901 | #endif | |
c6a556b8 | 902 | nfs_clear_page_writeback(req); |
1da177e4 LT |
903 | } |
904 | ||
905 | static inline int flush_task_priority(int how) | |
906 | { | |
907 | switch (how & (FLUSH_HIGHPRI|FLUSH_LOWPRI)) { | |
908 | case FLUSH_HIGHPRI: | |
909 | return RPC_PRIORITY_HIGH; | |
910 | case FLUSH_LOWPRI: | |
911 | return RPC_PRIORITY_LOW; | |
912 | } | |
913 | return RPC_PRIORITY_NORMAL; | |
914 | } | |
915 | ||
916 | /* | |
917 | * Set up the argument/result storage required for the RPC call. | |
918 | */ | |
919 | static void nfs_write_rpcsetup(struct nfs_page *req, | |
920 | struct nfs_write_data *data, | |
788e7a89 | 921 | const struct rpc_call_ops *call_ops, |
1da177e4 LT |
922 | unsigned int count, unsigned int offset, |
923 | int how) | |
924 | { | |
1da177e4 | 925 | struct inode *inode; |
788e7a89 | 926 | int flags; |
1da177e4 LT |
927 | |
928 | /* Set up the RPC argument and reply structs | |
929 | * NB: take care not to mess about with data->commit et al. */ | |
930 | ||
931 | data->req = req; | |
932 | data->inode = inode = req->wb_context->dentry->d_inode; | |
933 | data->cred = req->wb_context->cred; | |
934 | ||
935 | data->args.fh = NFS_FH(inode); | |
936 | data->args.offset = req_offset(req) + offset; | |
937 | data->args.pgbase = req->wb_pgbase + offset; | |
938 | data->args.pages = data->pagevec; | |
939 | data->args.count = count; | |
940 | data->args.context = req->wb_context; | |
941 | ||
942 | data->res.fattr = &data->fattr; | |
943 | data->res.count = count; | |
944 | data->res.verf = &data->verf; | |
0e574af1 | 945 | nfs_fattr_init(&data->fattr); |
1da177e4 | 946 | |
788e7a89 TM |
947 | /* Set up the initial task struct. */ |
948 | flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC; | |
949 | rpc_init_task(&data->task, NFS_CLIENT(inode), flags, call_ops, data); | |
1da177e4 LT |
950 | NFS_PROTO(inode)->write_setup(data, how); |
951 | ||
952 | data->task.tk_priority = flush_task_priority(how); | |
953 | data->task.tk_cookie = (unsigned long)inode; | |
1da177e4 LT |
954 | |
955 | dprintk("NFS: %4d initiated write call (req %s/%Ld, %u bytes @ offset %Lu)\n", | |
0bbacc40 | 956 | data->task.tk_pid, |
1da177e4 LT |
957 | inode->i_sb->s_id, |
958 | (long long)NFS_FILEID(inode), | |
959 | count, | |
960 | (unsigned long long)data->args.offset); | |
961 | } | |
962 | ||
963 | static void nfs_execute_write(struct nfs_write_data *data) | |
964 | { | |
965 | struct rpc_clnt *clnt = NFS_CLIENT(data->inode); | |
966 | sigset_t oldset; | |
967 | ||
968 | rpc_clnt_sigmask(clnt, &oldset); | |
969 | lock_kernel(); | |
970 | rpc_execute(&data->task); | |
971 | unlock_kernel(); | |
972 | rpc_clnt_sigunmask(clnt, &oldset); | |
973 | } | |
974 | ||
975 | /* | |
976 | * Generate multiple small requests to write out a single | |
977 | * contiguous dirty area on one page. | |
978 | */ | |
7d46a49f | 979 | static int nfs_flush_multi(struct inode *inode, struct list_head *head, int how) |
1da177e4 LT |
980 | { |
981 | struct nfs_page *req = nfs_list_entry(head->next); | |
982 | struct page *page = req->wb_page; | |
983 | struct nfs_write_data *data; | |
984 | unsigned int wsize = NFS_SERVER(inode)->wsize; | |
985 | unsigned int nbytes, offset; | |
986 | int requests = 0; | |
987 | LIST_HEAD(list); | |
988 | ||
989 | nfs_list_remove_request(req); | |
990 | ||
991 | nbytes = req->wb_bytes; | |
992 | for (;;) { | |
40859d7e | 993 | data = nfs_writedata_alloc(1); |
1da177e4 LT |
994 | if (!data) |
995 | goto out_bad; | |
996 | list_add(&data->pages, &list); | |
997 | requests++; | |
998 | if (nbytes <= wsize) | |
999 | break; | |
1000 | nbytes -= wsize; | |
1001 | } | |
1002 | atomic_set(&req->wb_complete, requests); | |
1003 | ||
1004 | ClearPageError(page); | |
bb713d6d | 1005 | set_page_writeback(page); |
1da177e4 LT |
1006 | offset = 0; |
1007 | nbytes = req->wb_bytes; | |
1008 | do { | |
1009 | data = list_entry(list.next, struct nfs_write_data, pages); | |
1010 | list_del_init(&data->pages); | |
1011 | ||
1012 | data->pagevec[0] = page; | |
1da177e4 LT |
1013 | |
1014 | if (nbytes > wsize) { | |
788e7a89 TM |
1015 | nfs_write_rpcsetup(req, data, &nfs_write_partial_ops, |
1016 | wsize, offset, how); | |
1da177e4 LT |
1017 | offset += wsize; |
1018 | nbytes -= wsize; | |
1019 | } else { | |
788e7a89 TM |
1020 | nfs_write_rpcsetup(req, data, &nfs_write_partial_ops, |
1021 | nbytes, offset, how); | |
1da177e4 LT |
1022 | nbytes = 0; |
1023 | } | |
1024 | nfs_execute_write(data); | |
1025 | } while (nbytes != 0); | |
1026 | ||
1027 | return 0; | |
1028 | ||
1029 | out_bad: | |
1030 | while (!list_empty(&list)) { | |
1031 | data = list_entry(list.next, struct nfs_write_data, pages); | |
1032 | list_del(&data->pages); | |
1033 | nfs_writedata_free(data); | |
1034 | } | |
1035 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1036 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1037 | return -ENOMEM; |
1038 | } | |
1039 | ||
1040 | /* | |
1041 | * Create an RPC task for the given write request and kick it. | |
1042 | * The page must have been locked by the caller. | |
1043 | * | |
1044 | * It may happen that the page we're passed is not marked dirty. | |
1045 | * This is the case if nfs_updatepage detects a conflicting request | |
1046 | * that has been written but not committed. | |
1047 | */ | |
7d46a49f | 1048 | static int nfs_flush_one(struct inode *inode, struct list_head *head, int how) |
1da177e4 LT |
1049 | { |
1050 | struct nfs_page *req; | |
1051 | struct page **pages; | |
1052 | struct nfs_write_data *data; | |
1053 | unsigned int count; | |
1054 | ||
40859d7e | 1055 | data = nfs_writedata_alloc(NFS_SERVER(inode)->wpages); |
1da177e4 LT |
1056 | if (!data) |
1057 | goto out_bad; | |
1058 | ||
1059 | pages = data->pagevec; | |
1060 | count = 0; | |
1061 | while (!list_empty(head)) { | |
1062 | req = nfs_list_entry(head->next); | |
1063 | nfs_list_remove_request(req); | |
1064 | nfs_list_add_request(req, &data->pages); | |
1065 | ClearPageError(req->wb_page); | |
bb713d6d | 1066 | set_page_writeback(req->wb_page); |
1da177e4 LT |
1067 | *pages++ = req->wb_page; |
1068 | count += req->wb_bytes; | |
1069 | } | |
1070 | req = nfs_list_entry(data->pages.next); | |
1071 | ||
1da177e4 | 1072 | /* Set up the argument struct */ |
788e7a89 | 1073 | nfs_write_rpcsetup(req, data, &nfs_write_full_ops, count, 0, how); |
1da177e4 LT |
1074 | |
1075 | nfs_execute_write(data); | |
1076 | return 0; | |
1077 | out_bad: | |
1078 | while (!list_empty(head)) { | |
1079 | struct nfs_page *req = nfs_list_entry(head->next); | |
1080 | nfs_list_remove_request(req); | |
1081 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1082 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1083 | } |
1084 | return -ENOMEM; | |
1085 | } | |
1086 | ||
7d46a49f | 1087 | static int nfs_flush_list(struct inode *inode, struct list_head *head, int npages, int how) |
1da177e4 LT |
1088 | { |
1089 | LIST_HEAD(one_request); | |
7d46a49f TM |
1090 | int (*flush_one)(struct inode *, struct list_head *, int); |
1091 | struct nfs_page *req; | |
1092 | int wpages = NFS_SERVER(inode)->wpages; | |
1093 | int wsize = NFS_SERVER(inode)->wsize; | |
1094 | int error; | |
1da177e4 | 1095 | |
7d46a49f TM |
1096 | flush_one = nfs_flush_one; |
1097 | if (wsize < PAGE_CACHE_SIZE) | |
1098 | flush_one = nfs_flush_multi; | |
1099 | /* For single writes, FLUSH_STABLE is more efficient */ | |
1100 | if (npages <= wpages && npages == NFS_I(inode)->npages | |
1101 | && nfs_list_entry(head->next)->wb_bytes <= wsize) | |
1102 | how |= FLUSH_STABLE; | |
1103 | ||
1104 | do { | |
1105 | nfs_coalesce_requests(head, &one_request, wpages); | |
1da177e4 | 1106 | req = nfs_list_entry(one_request.next); |
7d46a49f | 1107 | error = flush_one(inode, &one_request, how); |
1da177e4 | 1108 | if (error < 0) |
7d46a49f TM |
1109 | goto out_err; |
1110 | } while (!list_empty(head)); | |
1111 | return 0; | |
1112 | out_err: | |
1da177e4 LT |
1113 | while (!list_empty(head)) { |
1114 | req = nfs_list_entry(head->next); | |
1115 | nfs_list_remove_request(req); | |
1116 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1117 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1118 | } |
1119 | return error; | |
1120 | } | |
1121 | ||
1122 | /* | |
1123 | * Handle a write reply that flushed part of a page. | |
1124 | */ | |
788e7a89 | 1125 | static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata) |
1da177e4 | 1126 | { |
788e7a89 | 1127 | struct nfs_write_data *data = calldata; |
1da177e4 LT |
1128 | struct nfs_page *req = data->req; |
1129 | struct page *page = req->wb_page; | |
1130 | ||
1131 | dprintk("NFS: write (%s/%Ld %d@%Ld)", | |
1132 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1133 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1134 | req->wb_bytes, | |
1135 | (long long)req_offset(req)); | |
1136 | ||
788e7a89 TM |
1137 | if (nfs_writeback_done(task, data) != 0) |
1138 | return; | |
1139 | ||
1140 | if (task->tk_status < 0) { | |
1da177e4 LT |
1141 | ClearPageUptodate(page); |
1142 | SetPageError(page); | |
788e7a89 TM |
1143 | req->wb_context->error = task->tk_status; |
1144 | dprintk(", error = %d\n", task->tk_status); | |
1da177e4 LT |
1145 | } else { |
1146 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1147 | if (data->verf.committed < NFS_FILE_SYNC) { | |
1148 | if (!NFS_NEED_COMMIT(req)) { | |
1149 | nfs_defer_commit(req); | |
1150 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1151 | dprintk(" defer commit\n"); | |
1152 | } else if (memcmp(&req->wb_verf, &data->verf, sizeof(req->wb_verf))) { | |
1153 | nfs_defer_reschedule(req); | |
1154 | dprintk(" server reboot detected\n"); | |
1155 | } | |
1156 | } else | |
1157 | #endif | |
1158 | dprintk(" OK\n"); | |
1159 | } | |
1160 | ||
1161 | if (atomic_dec_and_test(&req->wb_complete)) | |
1162 | nfs_writepage_release(req); | |
1163 | } | |
1164 | ||
788e7a89 TM |
1165 | static const struct rpc_call_ops nfs_write_partial_ops = { |
1166 | .rpc_call_done = nfs_writeback_done_partial, | |
1167 | .rpc_release = nfs_writedata_release, | |
1168 | }; | |
1169 | ||
1da177e4 LT |
1170 | /* |
1171 | * Handle a write reply that flushes a whole page. | |
1172 | * | |
1173 | * FIXME: There is an inherent race with invalidate_inode_pages and | |
1174 | * writebacks since the page->count is kept > 1 for as long | |
1175 | * as the page has a write request pending. | |
1176 | */ | |
788e7a89 | 1177 | static void nfs_writeback_done_full(struct rpc_task *task, void *calldata) |
1da177e4 | 1178 | { |
788e7a89 | 1179 | struct nfs_write_data *data = calldata; |
1da177e4 LT |
1180 | struct nfs_page *req; |
1181 | struct page *page; | |
1182 | ||
788e7a89 TM |
1183 | if (nfs_writeback_done(task, data) != 0) |
1184 | return; | |
1185 | ||
1da177e4 LT |
1186 | /* Update attributes as result of writeback. */ |
1187 | while (!list_empty(&data->pages)) { | |
1188 | req = nfs_list_entry(data->pages.next); | |
1189 | nfs_list_remove_request(req); | |
1190 | page = req->wb_page; | |
1191 | ||
1192 | dprintk("NFS: write (%s/%Ld %d@%Ld)", | |
1193 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1194 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1195 | req->wb_bytes, | |
1196 | (long long)req_offset(req)); | |
1197 | ||
788e7a89 | 1198 | if (task->tk_status < 0) { |
1da177e4 LT |
1199 | ClearPageUptodate(page); |
1200 | SetPageError(page); | |
788e7a89 | 1201 | req->wb_context->error = task->tk_status; |
1da177e4 LT |
1202 | end_page_writeback(page); |
1203 | nfs_inode_remove_request(req); | |
788e7a89 | 1204 | dprintk(", error = %d\n", task->tk_status); |
1da177e4 LT |
1205 | goto next; |
1206 | } | |
1207 | end_page_writeback(page); | |
1208 | ||
1209 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1210 | if (data->args.stable != NFS_UNSTABLE || data->verf.committed == NFS_FILE_SYNC) { | |
1211 | nfs_inode_remove_request(req); | |
1212 | dprintk(" OK\n"); | |
1213 | goto next; | |
1214 | } | |
1215 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1216 | nfs_mark_request_commit(req); | |
1217 | dprintk(" marked for commit\n"); | |
1218 | #else | |
1219 | nfs_inode_remove_request(req); | |
1220 | #endif | |
1221 | next: | |
c6a556b8 | 1222 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1223 | } |
1224 | } | |
1225 | ||
788e7a89 TM |
1226 | static const struct rpc_call_ops nfs_write_full_ops = { |
1227 | .rpc_call_done = nfs_writeback_done_full, | |
1228 | .rpc_release = nfs_writedata_release, | |
1229 | }; | |
1230 | ||
1231 | ||
1da177e4 LT |
1232 | /* |
1233 | * This function is called when the WRITE call is complete. | |
1234 | */ | |
462d5b32 | 1235 | int nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data) |
1da177e4 | 1236 | { |
1da177e4 LT |
1237 | struct nfs_writeargs *argp = &data->args; |
1238 | struct nfs_writeres *resp = &data->res; | |
788e7a89 | 1239 | int status; |
1da177e4 LT |
1240 | |
1241 | dprintk("NFS: %4d nfs_writeback_done (status %d)\n", | |
1242 | task->tk_pid, task->tk_status); | |
1243 | ||
788e7a89 TM |
1244 | /* Call the NFS version-specific code */ |
1245 | status = NFS_PROTO(data->inode)->write_done(task, data); | |
1246 | if (status != 0) | |
1247 | return status; | |
91d5b470 CL |
1248 | nfs_add_stats(data->inode, NFSIOS_SERVERWRITTENBYTES, resp->count); |
1249 | ||
1da177e4 LT |
1250 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) |
1251 | if (resp->verf->committed < argp->stable && task->tk_status >= 0) { | |
1252 | /* We tried a write call, but the server did not | |
1253 | * commit data to stable storage even though we | |
1254 | * requested it. | |
1255 | * Note: There is a known bug in Tru64 < 5.0 in which | |
1256 | * the server reports NFS_DATA_SYNC, but performs | |
1257 | * NFS_FILE_SYNC. We therefore implement this checking | |
1258 | * as a dprintk() in order to avoid filling syslog. | |
1259 | */ | |
1260 | static unsigned long complain; | |
1261 | ||
1262 | if (time_before(complain, jiffies)) { | |
1263 | dprintk("NFS: faulty NFS server %s:" | |
1264 | " (committed = %d) != (stable = %d)\n", | |
1265 | NFS_SERVER(data->inode)->hostname, | |
1266 | resp->verf->committed, argp->stable); | |
1267 | complain = jiffies + 300 * HZ; | |
1268 | } | |
1269 | } | |
1270 | #endif | |
1271 | /* Is this a short write? */ | |
1272 | if (task->tk_status >= 0 && resp->count < argp->count) { | |
1273 | static unsigned long complain; | |
1274 | ||
91d5b470 CL |
1275 | nfs_inc_stats(data->inode, NFSIOS_SHORTWRITE); |
1276 | ||
1da177e4 LT |
1277 | /* Has the server at least made some progress? */ |
1278 | if (resp->count != 0) { | |
1279 | /* Was this an NFSv2 write or an NFSv3 stable write? */ | |
1280 | if (resp->verf->committed != NFS_UNSTABLE) { | |
1281 | /* Resend from where the server left off */ | |
1282 | argp->offset += resp->count; | |
1283 | argp->pgbase += resp->count; | |
1284 | argp->count -= resp->count; | |
1285 | } else { | |
1286 | /* Resend as a stable write in order to avoid | |
1287 | * headaches in the case of a server crash. | |
1288 | */ | |
1289 | argp->stable = NFS_FILE_SYNC; | |
1290 | } | |
1291 | rpc_restart_call(task); | |
788e7a89 | 1292 | return -EAGAIN; |
1da177e4 LT |
1293 | } |
1294 | if (time_before(complain, jiffies)) { | |
1295 | printk(KERN_WARNING | |
1296 | "NFS: Server wrote zero bytes, expected %u.\n", | |
1297 | argp->count); | |
1298 | complain = jiffies + 300 * HZ; | |
1299 | } | |
1300 | /* Can't do anything about it except throw an error. */ | |
1301 | task->tk_status = -EIO; | |
1302 | } | |
788e7a89 | 1303 | return 0; |
1da177e4 LT |
1304 | } |
1305 | ||
1306 | ||
1307 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
963d8fe5 | 1308 | void nfs_commit_release(void *wdata) |
1da177e4 | 1309 | { |
1da177e4 LT |
1310 | nfs_commit_free(wdata); |
1311 | } | |
1312 | ||
1313 | /* | |
1314 | * Set up the argument/result storage required for the RPC call. | |
1315 | */ | |
1316 | static void nfs_commit_rpcsetup(struct list_head *head, | |
788e7a89 TM |
1317 | struct nfs_write_data *data, |
1318 | int how) | |
1da177e4 | 1319 | { |
3da28eb1 | 1320 | struct nfs_page *first; |
1da177e4 | 1321 | struct inode *inode; |
788e7a89 | 1322 | int flags; |
1da177e4 LT |
1323 | |
1324 | /* Set up the RPC argument and reply structs | |
1325 | * NB: take care not to mess about with data->commit et al. */ | |
1326 | ||
1327 | list_splice_init(head, &data->pages); | |
1328 | first = nfs_list_entry(data->pages.next); | |
1da177e4 LT |
1329 | inode = first->wb_context->dentry->d_inode; |
1330 | ||
1da177e4 LT |
1331 | data->inode = inode; |
1332 | data->cred = first->wb_context->cred; | |
1333 | ||
1334 | data->args.fh = NFS_FH(data->inode); | |
3da28eb1 TM |
1335 | /* Note: we always request a commit of the entire inode */ |
1336 | data->args.offset = 0; | |
1337 | data->args.count = 0; | |
1338 | data->res.count = 0; | |
1da177e4 LT |
1339 | data->res.fattr = &data->fattr; |
1340 | data->res.verf = &data->verf; | |
0e574af1 | 1341 | nfs_fattr_init(&data->fattr); |
788e7a89 TM |
1342 | |
1343 | /* Set up the initial task struct. */ | |
1344 | flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC; | |
1345 | rpc_init_task(&data->task, NFS_CLIENT(inode), flags, &nfs_commit_ops, data); | |
1da177e4 LT |
1346 | NFS_PROTO(inode)->commit_setup(data, how); |
1347 | ||
1348 | data->task.tk_priority = flush_task_priority(how); | |
1349 | data->task.tk_cookie = (unsigned long)inode; | |
1da177e4 | 1350 | |
0bbacc40 | 1351 | dprintk("NFS: %4d initiated commit call\n", data->task.tk_pid); |
1da177e4 LT |
1352 | } |
1353 | ||
1354 | /* | |
1355 | * Commit dirty pages | |
1356 | */ | |
1357 | static int | |
40859d7e | 1358 | nfs_commit_list(struct inode *inode, struct list_head *head, int how) |
1da177e4 LT |
1359 | { |
1360 | struct nfs_write_data *data; | |
1361 | struct nfs_page *req; | |
1362 | ||
40859d7e | 1363 | data = nfs_commit_alloc(NFS_SERVER(inode)->wpages); |
1da177e4 LT |
1364 | |
1365 | if (!data) | |
1366 | goto out_bad; | |
1367 | ||
1368 | /* Set up the argument struct */ | |
1369 | nfs_commit_rpcsetup(head, data, how); | |
1370 | ||
1371 | nfs_execute_write(data); | |
1372 | return 0; | |
1373 | out_bad: | |
1374 | while (!list_empty(head)) { | |
1375 | req = nfs_list_entry(head->next); | |
1376 | nfs_list_remove_request(req); | |
1377 | nfs_mark_request_commit(req); | |
c6a556b8 | 1378 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1379 | } |
1380 | return -ENOMEM; | |
1381 | } | |
1382 | ||
1383 | /* | |
1384 | * COMMIT call returned | |
1385 | */ | |
788e7a89 | 1386 | static void nfs_commit_done(struct rpc_task *task, void *calldata) |
1da177e4 | 1387 | { |
963d8fe5 | 1388 | struct nfs_write_data *data = calldata; |
1da177e4 LT |
1389 | struct nfs_page *req; |
1390 | int res = 0; | |
1391 | ||
1392 | dprintk("NFS: %4d nfs_commit_done (status %d)\n", | |
1393 | task->tk_pid, task->tk_status); | |
1394 | ||
788e7a89 TM |
1395 | /* Call the NFS version-specific code */ |
1396 | if (NFS_PROTO(data->inode)->commit_done(task, data) != 0) | |
1397 | return; | |
1398 | ||
1da177e4 LT |
1399 | while (!list_empty(&data->pages)) { |
1400 | req = nfs_list_entry(data->pages.next); | |
1401 | nfs_list_remove_request(req); | |
1402 | ||
1403 | dprintk("NFS: commit (%s/%Ld %d@%Ld)", | |
1404 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1405 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1406 | req->wb_bytes, | |
1407 | (long long)req_offset(req)); | |
1408 | if (task->tk_status < 0) { | |
1409 | req->wb_context->error = task->tk_status; | |
1410 | nfs_inode_remove_request(req); | |
1411 | dprintk(", error = %d\n", task->tk_status); | |
1412 | goto next; | |
1413 | } | |
1414 | ||
1415 | /* Okay, COMMIT succeeded, apparently. Check the verifier | |
1416 | * returned by the server against all stored verfs. */ | |
1417 | if (!memcmp(req->wb_verf.verifier, data->verf.verifier, sizeof(data->verf.verifier))) { | |
1418 | /* We have a match */ | |
1419 | nfs_inode_remove_request(req); | |
1420 | dprintk(" OK\n"); | |
1421 | goto next; | |
1422 | } | |
1423 | /* We have a mismatch. Write the page again */ | |
1424 | dprintk(" mismatch\n"); | |
1425 | nfs_mark_request_dirty(req); | |
1426 | next: | |
c6a556b8 | 1427 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1428 | res++; |
1429 | } | |
1430 | sub_page_state(nr_unstable,res); | |
1431 | } | |
788e7a89 TM |
1432 | |
1433 | static const struct rpc_call_ops nfs_commit_ops = { | |
1434 | .rpc_call_done = nfs_commit_done, | |
1435 | .rpc_release = nfs_commit_release, | |
1436 | }; | |
c42de9dd TM |
1437 | #else |
1438 | static inline int nfs_commit_list(struct inode *inode, struct list_head *head, int how) | |
1439 | { | |
1440 | return 0; | |
1441 | } | |
1da177e4 LT |
1442 | #endif |
1443 | ||
1444 | static int nfs_flush_inode(struct inode *inode, unsigned long idx_start, | |
1445 | unsigned int npages, int how) | |
1446 | { | |
1447 | struct nfs_inode *nfsi = NFS_I(inode); | |
1448 | LIST_HEAD(head); | |
7d46a49f | 1449 | int res; |
1da177e4 LT |
1450 | |
1451 | spin_lock(&nfsi->req_lock); | |
1452 | res = nfs_scan_dirty(inode, &head, idx_start, npages); | |
1453 | spin_unlock(&nfsi->req_lock); | |
ab0a3dbe | 1454 | if (res) { |
7d46a49f TM |
1455 | int error = nfs_flush_list(inode, &head, res, how); |
1456 | if (error < 0) | |
1457 | return error; | |
ab0a3dbe | 1458 | } |
1da177e4 LT |
1459 | return res; |
1460 | } | |
1461 | ||
1462 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
3da28eb1 | 1463 | int nfs_commit_inode(struct inode *inode, int how) |
1da177e4 LT |
1464 | { |
1465 | struct nfs_inode *nfsi = NFS_I(inode); | |
1466 | LIST_HEAD(head); | |
7d46a49f | 1467 | int res; |
1da177e4 LT |
1468 | |
1469 | spin_lock(&nfsi->req_lock); | |
3da28eb1 TM |
1470 | res = nfs_scan_commit(inode, &head, 0, 0); |
1471 | spin_unlock(&nfsi->req_lock); | |
1da177e4 | 1472 | if (res) { |
7d46a49f | 1473 | int error = nfs_commit_list(inode, &head, how); |
3da28eb1 TM |
1474 | if (error < 0) |
1475 | return error; | |
1476 | } | |
1da177e4 LT |
1477 | return res; |
1478 | } | |
1479 | #endif | |
1480 | ||
c42de9dd TM |
1481 | int nfs_sync_inode_wait(struct inode *inode, unsigned long idx_start, |
1482 | unsigned int npages, int how) | |
1da177e4 | 1483 | { |
c42de9dd TM |
1484 | struct nfs_inode *nfsi = NFS_I(inode); |
1485 | LIST_HEAD(head); | |
70b9ecbd | 1486 | int nocommit = how & FLUSH_NOCOMMIT; |
c42de9dd | 1487 | int pages, ret; |
1da177e4 | 1488 | |
c42de9dd TM |
1489 | how &= ~FLUSH_NOCOMMIT; |
1490 | spin_lock(&nfsi->req_lock); | |
1da177e4 | 1491 | do { |
c42de9dd TM |
1492 | ret = nfs_wait_on_requests_locked(inode, idx_start, npages); |
1493 | if (ret != 0) | |
70b9ecbd | 1494 | continue; |
c42de9dd TM |
1495 | pages = nfs_scan_dirty(inode, &head, idx_start, npages); |
1496 | if (pages != 0) { | |
1497 | spin_unlock(&nfsi->req_lock); | |
1498 | ret = nfs_flush_list(inode, &head, pages, how); | |
1499 | spin_lock(&nfsi->req_lock); | |
1500 | continue; | |
1501 | } | |
1502 | if (nocommit) | |
1503 | break; | |
1504 | pages = nfs_scan_commit(inode, &head, 0, 0); | |
1505 | if (pages == 0) | |
1506 | break; | |
1507 | spin_unlock(&nfsi->req_lock); | |
1508 | ret = nfs_commit_list(inode, &head, how); | |
1509 | spin_lock(&nfsi->req_lock); | |
1510 | } while (ret >= 0); | |
1511 | spin_unlock(&nfsi->req_lock); | |
1512 | return ret; | |
1da177e4 LT |
1513 | } |
1514 | ||
1515 | int nfs_init_writepagecache(void) | |
1516 | { | |
1517 | nfs_wdata_cachep = kmem_cache_create("nfs_write_data", | |
1518 | sizeof(struct nfs_write_data), | |
1519 | 0, SLAB_HWCACHE_ALIGN, | |
1520 | NULL, NULL); | |
1521 | if (nfs_wdata_cachep == NULL) | |
1522 | return -ENOMEM; | |
1523 | ||
93d2341c MD |
1524 | nfs_wdata_mempool = mempool_create_slab_pool(MIN_POOL_WRITE, |
1525 | nfs_wdata_cachep); | |
1da177e4 LT |
1526 | if (nfs_wdata_mempool == NULL) |
1527 | return -ENOMEM; | |
1528 | ||
93d2341c MD |
1529 | nfs_commit_mempool = mempool_create_slab_pool(MIN_POOL_COMMIT, |
1530 | nfs_wdata_cachep); | |
1da177e4 LT |
1531 | if (nfs_commit_mempool == NULL) |
1532 | return -ENOMEM; | |
1533 | ||
1534 | return 0; | |
1535 | } | |
1536 | ||
1537 | void nfs_destroy_writepagecache(void) | |
1538 | { | |
1539 | mempool_destroy(nfs_commit_mempool); | |
1540 | mempool_destroy(nfs_wdata_mempool); | |
1541 | if (kmem_cache_destroy(nfs_wdata_cachep)) | |
1542 | printk(KERN_INFO "nfs_write_data: not all structures were freed\n"); | |
1543 | } | |
1544 |