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); | |
0d0b5cb3 CL |
101 | if (pagecount <= ARRAY_SIZE(p->page_array)) |
102 | p->pagevec = p->page_array; | |
40859d7e | 103 | else { |
0d0b5cb3 | 104 | p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_NOFS); |
bd647545 | 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 | ||
e17b1fc4 | 114 | void nfs_commit_free(struct nfs_write_data *p) |
1da177e4 | 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 | ||
3feb2d49 TM |
121 | struct nfs_write_data *nfs_writedata_alloc(unsigned int pagecount) |
122 | { | |
123 | struct nfs_write_data *p = mempool_alloc(nfs_wdata_mempool, SLAB_NOFS); | |
124 | ||
125 | if (p) { | |
126 | memset(p, 0, sizeof(*p)); | |
127 | INIT_LIST_HEAD(&p->pages); | |
0d0b5cb3 CL |
128 | if (pagecount <= ARRAY_SIZE(p->page_array)) |
129 | p->pagevec = p->page_array; | |
3feb2d49 | 130 | else { |
0d0b5cb3 CL |
131 | p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_NOFS); |
132 | if (!p->pagevec) { | |
3feb2d49 TM |
133 | mempool_free(p, nfs_wdata_mempool); |
134 | p = NULL; | |
135 | } | |
136 | } | |
137 | } | |
138 | return p; | |
139 | } | |
140 | ||
141 | void nfs_writedata_free(struct nfs_write_data *p) | |
142 | { | |
143 | if (p && (p->pagevec != &p->page_array[0])) | |
144 | kfree(p->pagevec); | |
145 | mempool_free(p, nfs_wdata_mempool); | |
146 | } | |
147 | ||
963d8fe5 | 148 | void nfs_writedata_release(void *wdata) |
1da177e4 | 149 | { |
1da177e4 LT |
150 | nfs_writedata_free(wdata); |
151 | } | |
152 | ||
153 | /* Adjust the file length if we're writing beyond the end */ | |
154 | static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count) | |
155 | { | |
156 | struct inode *inode = page->mapping->host; | |
157 | loff_t end, i_size = i_size_read(inode); | |
158 | unsigned long end_index = (i_size - 1) >> PAGE_CACHE_SHIFT; | |
159 | ||
160 | if (i_size > 0 && page->index < end_index) | |
161 | return; | |
162 | end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + ((loff_t)offset+count); | |
163 | if (i_size >= end) | |
164 | return; | |
91d5b470 | 165 | nfs_inc_stats(inode, NFSIOS_EXTENDWRITE); |
1da177e4 LT |
166 | i_size_write(inode, end); |
167 | } | |
168 | ||
169 | /* We can set the PG_uptodate flag if we see that a write request | |
170 | * covers the full page. | |
171 | */ | |
172 | static void nfs_mark_uptodate(struct page *page, unsigned int base, unsigned int count) | |
173 | { | |
174 | loff_t end_offs; | |
175 | ||
176 | if (PageUptodate(page)) | |
177 | return; | |
178 | if (base != 0) | |
179 | return; | |
180 | if (count == PAGE_CACHE_SIZE) { | |
181 | SetPageUptodate(page); | |
182 | return; | |
183 | } | |
184 | ||
185 | end_offs = i_size_read(page->mapping->host) - 1; | |
186 | if (end_offs < 0) | |
187 | return; | |
188 | /* Is this the last page? */ | |
189 | if (page->index != (unsigned long)(end_offs >> PAGE_CACHE_SHIFT)) | |
190 | return; | |
191 | /* This is the last page: set PG_uptodate if we cover the entire | |
192 | * extent of the data, then zero the rest of the page. | |
193 | */ | |
194 | if (count == (unsigned int)(end_offs & (PAGE_CACHE_SIZE - 1)) + 1) { | |
195 | memclear_highpage_flush(page, count, PAGE_CACHE_SIZE - count); | |
196 | SetPageUptodate(page); | |
197 | } | |
198 | } | |
199 | ||
200 | /* | |
201 | * Write a page synchronously. | |
202 | * Offset is the data offset within the page. | |
203 | */ | |
204 | static int nfs_writepage_sync(struct nfs_open_context *ctx, struct inode *inode, | |
205 | struct page *page, unsigned int offset, unsigned int count, | |
206 | int how) | |
207 | { | |
208 | unsigned int wsize = NFS_SERVER(inode)->wsize; | |
209 | int result, written = 0; | |
210 | struct nfs_write_data *wdata; | |
211 | ||
40859d7e | 212 | wdata = nfs_writedata_alloc(1); |
1da177e4 LT |
213 | if (!wdata) |
214 | return -ENOMEM; | |
215 | ||
216 | wdata->flags = how; | |
217 | wdata->cred = ctx->cred; | |
218 | wdata->inode = inode; | |
219 | wdata->args.fh = NFS_FH(inode); | |
220 | wdata->args.context = ctx; | |
221 | wdata->args.pages = &page; | |
222 | wdata->args.stable = NFS_FILE_SYNC; | |
223 | wdata->args.pgbase = offset; | |
224 | wdata->args.count = wsize; | |
225 | wdata->res.fattr = &wdata->fattr; | |
226 | wdata->res.verf = &wdata->verf; | |
227 | ||
228 | dprintk("NFS: nfs_writepage_sync(%s/%Ld %d@%Ld)\n", | |
229 | inode->i_sb->s_id, | |
230 | (long long)NFS_FILEID(inode), | |
231 | count, (long long)(page_offset(page) + offset)); | |
232 | ||
bb713d6d | 233 | set_page_writeback(page); |
1da177e4 LT |
234 | nfs_begin_data_update(inode); |
235 | do { | |
236 | if (count < wsize) | |
237 | wdata->args.count = count; | |
238 | wdata->args.offset = page_offset(page) + wdata->args.pgbase; | |
239 | ||
240 | result = NFS_PROTO(inode)->write(wdata); | |
241 | ||
242 | if (result < 0) { | |
243 | /* Must mark the page invalid after I/O error */ | |
244 | ClearPageUptodate(page); | |
245 | goto io_error; | |
246 | } | |
247 | if (result < wdata->args.count) | |
248 | printk(KERN_WARNING "NFS: short write, count=%u, result=%d\n", | |
249 | wdata->args.count, result); | |
250 | ||
251 | wdata->args.offset += result; | |
252 | wdata->args.pgbase += result; | |
253 | written += result; | |
254 | count -= result; | |
91d5b470 | 255 | nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, result); |
1da177e4 LT |
256 | } while (count); |
257 | /* Update file length */ | |
258 | nfs_grow_file(page, offset, written); | |
259 | /* Set the PG_uptodate flag? */ | |
260 | nfs_mark_uptodate(page, offset, written); | |
261 | ||
262 | if (PageError(page)) | |
263 | ClearPageError(page); | |
264 | ||
265 | io_error: | |
951a143b | 266 | nfs_end_data_update(inode); |
bb713d6d | 267 | end_page_writeback(page); |
1da177e4 LT |
268 | nfs_writedata_free(wdata); |
269 | return written ? written : result; | |
270 | } | |
271 | ||
272 | static int nfs_writepage_async(struct nfs_open_context *ctx, | |
273 | struct inode *inode, struct page *page, | |
274 | unsigned int offset, unsigned int count) | |
275 | { | |
276 | struct nfs_page *req; | |
1da177e4 LT |
277 | |
278 | req = nfs_update_request(ctx, inode, page, offset, count); | |
abd3e641 TM |
279 | if (IS_ERR(req)) |
280 | return PTR_ERR(req); | |
1da177e4 LT |
281 | /* Update file length */ |
282 | nfs_grow_file(page, offset, count); | |
283 | /* Set the PG_uptodate flag? */ | |
284 | nfs_mark_uptodate(page, offset, count); | |
285 | nfs_unlock_request(req); | |
abd3e641 | 286 | return 0; |
1da177e4 LT |
287 | } |
288 | ||
289 | static int wb_priority(struct writeback_control *wbc) | |
290 | { | |
291 | if (wbc->for_reclaim) | |
292 | return FLUSH_HIGHPRI; | |
293 | if (wbc->for_kupdate) | |
294 | return FLUSH_LOWPRI; | |
295 | return 0; | |
296 | } | |
297 | ||
298 | /* | |
299 | * Write an mmapped page to the server. | |
300 | */ | |
301 | int nfs_writepage(struct page *page, struct writeback_control *wbc) | |
302 | { | |
303 | struct nfs_open_context *ctx; | |
304 | struct inode *inode = page->mapping->host; | |
305 | unsigned long end_index; | |
306 | unsigned offset = PAGE_CACHE_SIZE; | |
307 | loff_t i_size = i_size_read(inode); | |
308 | int inode_referenced = 0; | |
309 | int priority = wb_priority(wbc); | |
310 | int err; | |
311 | ||
91d5b470 CL |
312 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); |
313 | nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1); | |
314 | ||
1da177e4 LT |
315 | /* |
316 | * Note: We need to ensure that we have a reference to the inode | |
317 | * if we are to do asynchronous writes. If not, waiting | |
318 | * in nfs_wait_on_request() may deadlock with clear_inode(). | |
319 | * | |
320 | * If igrab() fails here, then it is in any case safe to | |
321 | * call nfs_wb_page(), since there will be no pending writes. | |
322 | */ | |
323 | if (igrab(inode) != 0) | |
324 | inode_referenced = 1; | |
325 | end_index = i_size >> PAGE_CACHE_SHIFT; | |
326 | ||
327 | /* Ensure we've flushed out any previous writes */ | |
328 | nfs_wb_page_priority(inode, page, priority); | |
329 | ||
330 | /* easy case */ | |
331 | if (page->index < end_index) | |
332 | goto do_it; | |
333 | /* things got complicated... */ | |
334 | offset = i_size & (PAGE_CACHE_SIZE-1); | |
335 | ||
336 | /* OK, are we completely out? */ | |
337 | err = 0; /* potential race with truncate - ignore */ | |
338 | if (page->index >= end_index+1 || !offset) | |
339 | goto out; | |
340 | do_it: | |
d530838b | 341 | ctx = nfs_find_open_context(inode, NULL, FMODE_WRITE); |
1da177e4 LT |
342 | if (ctx == NULL) { |
343 | err = -EBADF; | |
344 | goto out; | |
345 | } | |
346 | lock_kernel(); | |
347 | if (!IS_SYNC(inode) && inode_referenced) { | |
348 | err = nfs_writepage_async(ctx, inode, page, 0, offset); | |
abd3e641 TM |
349 | if (!wbc->for_writepages) |
350 | nfs_flush_inode(inode, 0, 0, wb_priority(wbc)); | |
1da177e4 LT |
351 | } else { |
352 | err = nfs_writepage_sync(ctx, inode, page, 0, | |
353 | offset, priority); | |
354 | if (err >= 0) { | |
355 | if (err != offset) | |
356 | redirty_page_for_writepage(wbc, page); | |
357 | err = 0; | |
358 | } | |
359 | } | |
360 | unlock_kernel(); | |
361 | put_nfs_open_context(ctx); | |
362 | out: | |
363 | unlock_page(page); | |
364 | if (inode_referenced) | |
365 | iput(inode); | |
366 | return err; | |
367 | } | |
368 | ||
369 | /* | |
370 | * Note: causes nfs_update_request() to block on the assumption | |
371 | * that the writeback is generated due to memory pressure. | |
372 | */ | |
373 | int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) | |
374 | { | |
375 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
376 | struct inode *inode = mapping->host; | |
377 | int err; | |
378 | ||
91d5b470 CL |
379 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); |
380 | ||
1da177e4 LT |
381 | err = generic_writepages(mapping, wbc); |
382 | if (err) | |
383 | return err; | |
384 | while (test_and_set_bit(BDI_write_congested, &bdi->state) != 0) { | |
385 | if (wbc->nonblocking) | |
386 | return 0; | |
387 | nfs_wait_on_write_congestion(mapping, 0); | |
388 | } | |
389 | err = nfs_flush_inode(inode, 0, 0, wb_priority(wbc)); | |
390 | if (err < 0) | |
391 | goto out; | |
91d5b470 | 392 | nfs_add_stats(inode, NFSIOS_WRITEPAGES, err); |
1da177e4 LT |
393 | wbc->nr_to_write -= err; |
394 | if (!wbc->nonblocking && wbc->sync_mode == WB_SYNC_ALL) { | |
395 | err = nfs_wait_on_requests(inode, 0, 0); | |
396 | if (err < 0) | |
397 | goto out; | |
398 | } | |
3da28eb1 | 399 | err = nfs_commit_inode(inode, wb_priority(wbc)); |
1da177e4 LT |
400 | if (err > 0) { |
401 | wbc->nr_to_write -= err; | |
402 | err = 0; | |
403 | } | |
404 | out: | |
405 | clear_bit(BDI_write_congested, &bdi->state); | |
406 | wake_up_all(&nfs_write_congestion); | |
407 | return err; | |
408 | } | |
409 | ||
410 | /* | |
411 | * Insert a write request into an inode | |
412 | */ | |
413 | static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req) | |
414 | { | |
415 | struct nfs_inode *nfsi = NFS_I(inode); | |
416 | int error; | |
417 | ||
418 | error = radix_tree_insert(&nfsi->nfs_page_tree, req->wb_index, req); | |
419 | BUG_ON(error == -EEXIST); | |
420 | if (error) | |
421 | return error; | |
422 | if (!nfsi->npages) { | |
423 | igrab(inode); | |
424 | nfs_begin_data_update(inode); | |
425 | if (nfs_have_delegation(inode, FMODE_WRITE)) | |
426 | nfsi->change_attr++; | |
427 | } | |
deb7d638 | 428 | SetPagePrivate(req->wb_page); |
1da177e4 LT |
429 | nfsi->npages++; |
430 | atomic_inc(&req->wb_count); | |
431 | return 0; | |
432 | } | |
433 | ||
434 | /* | |
435 | * Insert a write request into an inode | |
436 | */ | |
437 | static void nfs_inode_remove_request(struct nfs_page *req) | |
438 | { | |
439 | struct inode *inode = req->wb_context->dentry->d_inode; | |
440 | struct nfs_inode *nfsi = NFS_I(inode); | |
441 | ||
442 | BUG_ON (!NFS_WBACK_BUSY(req)); | |
443 | ||
444 | spin_lock(&nfsi->req_lock); | |
deb7d638 | 445 | ClearPagePrivate(req->wb_page); |
1da177e4 LT |
446 | radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index); |
447 | nfsi->npages--; | |
448 | if (!nfsi->npages) { | |
449 | spin_unlock(&nfsi->req_lock); | |
951a143b | 450 | nfs_end_data_update(inode); |
1da177e4 LT |
451 | iput(inode); |
452 | } else | |
453 | spin_unlock(&nfsi->req_lock); | |
454 | nfs_clear_request(req); | |
455 | nfs_release_request(req); | |
456 | } | |
457 | ||
458 | /* | |
459 | * Find a request | |
460 | */ | |
461 | static inline struct nfs_page * | |
462 | _nfs_find_request(struct inode *inode, unsigned long index) | |
463 | { | |
464 | struct nfs_inode *nfsi = NFS_I(inode); | |
465 | struct nfs_page *req; | |
466 | ||
467 | req = (struct nfs_page*)radix_tree_lookup(&nfsi->nfs_page_tree, index); | |
468 | if (req) | |
469 | atomic_inc(&req->wb_count); | |
470 | return req; | |
471 | } | |
472 | ||
473 | static struct nfs_page * | |
474 | nfs_find_request(struct inode *inode, unsigned long index) | |
475 | { | |
476 | struct nfs_page *req; | |
477 | struct nfs_inode *nfsi = NFS_I(inode); | |
478 | ||
479 | spin_lock(&nfsi->req_lock); | |
480 | req = _nfs_find_request(inode, index); | |
481 | spin_unlock(&nfsi->req_lock); | |
482 | return req; | |
483 | } | |
484 | ||
485 | /* | |
486 | * Add a request to the inode's dirty list. | |
487 | */ | |
488 | static void | |
489 | nfs_mark_request_dirty(struct nfs_page *req) | |
490 | { | |
491 | struct inode *inode = req->wb_context->dentry->d_inode; | |
492 | struct nfs_inode *nfsi = NFS_I(inode); | |
493 | ||
494 | spin_lock(&nfsi->req_lock); | |
3da28eb1 TM |
495 | radix_tree_tag_set(&nfsi->nfs_page_tree, |
496 | req->wb_index, NFS_PAGE_TAG_DIRTY); | |
1da177e4 LT |
497 | nfs_list_add_request(req, &nfsi->dirty); |
498 | nfsi->ndirty++; | |
499 | spin_unlock(&nfsi->req_lock); | |
500 | inc_page_state(nr_dirty); | |
501 | mark_inode_dirty(inode); | |
502 | } | |
503 | ||
504 | /* | |
505 | * Check if a request is dirty | |
506 | */ | |
507 | static inline int | |
508 | nfs_dirty_request(struct nfs_page *req) | |
509 | { | |
510 | struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode); | |
511 | return !list_empty(&req->wb_list) && req->wb_list_head == &nfsi->dirty; | |
512 | } | |
513 | ||
514 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
515 | /* | |
516 | * Add a request to the inode's commit list. | |
517 | */ | |
518 | static void | |
519 | nfs_mark_request_commit(struct nfs_page *req) | |
520 | { | |
521 | struct inode *inode = req->wb_context->dentry->d_inode; | |
522 | struct nfs_inode *nfsi = NFS_I(inode); | |
523 | ||
524 | spin_lock(&nfsi->req_lock); | |
525 | nfs_list_add_request(req, &nfsi->commit); | |
526 | nfsi->ncommit++; | |
527 | spin_unlock(&nfsi->req_lock); | |
528 | inc_page_state(nr_unstable); | |
529 | mark_inode_dirty(inode); | |
530 | } | |
531 | #endif | |
532 | ||
533 | /* | |
534 | * Wait for a request to complete. | |
535 | * | |
536 | * Interruptible by signals only if mounted with intr flag. | |
537 | */ | |
c42de9dd | 538 | static int nfs_wait_on_requests_locked(struct inode *inode, unsigned long idx_start, unsigned int npages) |
1da177e4 LT |
539 | { |
540 | struct nfs_inode *nfsi = NFS_I(inode); | |
541 | struct nfs_page *req; | |
542 | unsigned long idx_end, next; | |
543 | unsigned int res = 0; | |
544 | int error; | |
545 | ||
546 | if (npages == 0) | |
547 | idx_end = ~0; | |
548 | else | |
549 | idx_end = idx_start + npages - 1; | |
550 | ||
1da177e4 | 551 | next = idx_start; |
c6a556b8 | 552 | while (radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree, (void **)&req, next, 1, NFS_PAGE_TAG_WRITEBACK)) { |
1da177e4 LT |
553 | if (req->wb_index > idx_end) |
554 | break; | |
555 | ||
556 | next = req->wb_index + 1; | |
c6a556b8 | 557 | BUG_ON(!NFS_WBACK_BUSY(req)); |
1da177e4 LT |
558 | |
559 | atomic_inc(&req->wb_count); | |
560 | spin_unlock(&nfsi->req_lock); | |
561 | error = nfs_wait_on_request(req); | |
562 | nfs_release_request(req); | |
c42de9dd | 563 | spin_lock(&nfsi->req_lock); |
1da177e4 LT |
564 | if (error < 0) |
565 | return error; | |
1da177e4 LT |
566 | res++; |
567 | } | |
1da177e4 LT |
568 | return res; |
569 | } | |
570 | ||
c42de9dd TM |
571 | static int nfs_wait_on_requests(struct inode *inode, unsigned long idx_start, unsigned int npages) |
572 | { | |
573 | struct nfs_inode *nfsi = NFS_I(inode); | |
574 | int ret; | |
575 | ||
576 | spin_lock(&nfsi->req_lock); | |
577 | ret = nfs_wait_on_requests_locked(inode, idx_start, npages); | |
578 | spin_unlock(&nfsi->req_lock); | |
579 | return ret; | |
580 | } | |
581 | ||
d2ccddf0 TM |
582 | static void nfs_cancel_requests(struct list_head *head) |
583 | { | |
584 | struct nfs_page *req; | |
585 | while(!list_empty(head)) { | |
586 | req = nfs_list_entry(head->next); | |
587 | nfs_list_remove_request(req); | |
588 | nfs_inode_remove_request(req); | |
589 | nfs_clear_page_writeback(req); | |
590 | } | |
591 | } | |
592 | ||
1da177e4 LT |
593 | /* |
594 | * nfs_scan_dirty - Scan an inode for dirty requests | |
595 | * @inode: NFS inode to scan | |
596 | * @dst: destination list | |
597 | * @idx_start: lower bound of page->index to scan. | |
598 | * @npages: idx_start + npages sets the upper bound to scan. | |
599 | * | |
600 | * Moves requests from the inode's dirty page list. | |
601 | * The requests are *not* checked to ensure that they form a contiguous set. | |
602 | */ | |
603 | static int | |
604 | nfs_scan_dirty(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
605 | { | |
606 | struct nfs_inode *nfsi = NFS_I(inode); | |
3da28eb1 TM |
607 | int res = 0; |
608 | ||
609 | if (nfsi->ndirty != 0) { | |
610 | res = nfs_scan_lock_dirty(nfsi, dst, idx_start, npages); | |
611 | nfsi->ndirty -= res; | |
612 | sub_page_state(nr_dirty,res); | |
613 | if ((nfsi->ndirty == 0) != list_empty(&nfsi->dirty)) | |
614 | printk(KERN_ERR "NFS: desynchronized value of nfs_i.ndirty.\n"); | |
615 | } | |
1da177e4 LT |
616 | return res; |
617 | } | |
618 | ||
619 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
620 | /* | |
621 | * nfs_scan_commit - Scan an inode for commit requests | |
622 | * @inode: NFS inode to scan | |
623 | * @dst: destination list | |
624 | * @idx_start: lower bound of page->index to scan. | |
625 | * @npages: idx_start + npages sets the upper bound to scan. | |
626 | * | |
627 | * Moves requests from the inode's 'commit' request list. | |
628 | * The requests are *not* checked to ensure that they form a contiguous set. | |
629 | */ | |
630 | static int | |
631 | nfs_scan_commit(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
632 | { | |
633 | struct nfs_inode *nfsi = NFS_I(inode); | |
3da28eb1 TM |
634 | int res = 0; |
635 | ||
636 | if (nfsi->ncommit != 0) { | |
d2ccddf0 | 637 | res = nfs_scan_list(nfsi, &nfsi->commit, dst, idx_start, npages); |
3da28eb1 TM |
638 | nfsi->ncommit -= res; |
639 | if ((nfsi->ncommit == 0) != list_empty(&nfsi->commit)) | |
640 | printk(KERN_ERR "NFS: desynchronized value of nfs_i.ncommit.\n"); | |
641 | } | |
1da177e4 LT |
642 | return res; |
643 | } | |
c42de9dd TM |
644 | #else |
645 | static inline int nfs_scan_commit(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
646 | { | |
647 | return 0; | |
648 | } | |
1da177e4 LT |
649 | #endif |
650 | ||
651 | static int nfs_wait_on_write_congestion(struct address_space *mapping, int intr) | |
652 | { | |
653 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
654 | DEFINE_WAIT(wait); | |
655 | int ret = 0; | |
656 | ||
657 | might_sleep(); | |
658 | ||
659 | if (!bdi_write_congested(bdi)) | |
660 | return 0; | |
91d5b470 CL |
661 | |
662 | nfs_inc_stats(mapping->host, NFSIOS_CONGESTIONWAIT); | |
663 | ||
1da177e4 LT |
664 | if (intr) { |
665 | struct rpc_clnt *clnt = NFS_CLIENT(mapping->host); | |
666 | sigset_t oldset; | |
667 | ||
668 | rpc_clnt_sigmask(clnt, &oldset); | |
669 | prepare_to_wait(&nfs_write_congestion, &wait, TASK_INTERRUPTIBLE); | |
670 | if (bdi_write_congested(bdi)) { | |
671 | if (signalled()) | |
672 | ret = -ERESTARTSYS; | |
673 | else | |
674 | schedule(); | |
675 | } | |
676 | rpc_clnt_sigunmask(clnt, &oldset); | |
677 | } else { | |
678 | prepare_to_wait(&nfs_write_congestion, &wait, TASK_UNINTERRUPTIBLE); | |
679 | if (bdi_write_congested(bdi)) | |
680 | schedule(); | |
681 | } | |
682 | finish_wait(&nfs_write_congestion, &wait); | |
683 | return ret; | |
684 | } | |
685 | ||
686 | ||
687 | /* | |
688 | * Try to update any existing write request, or create one if there is none. | |
689 | * In order to match, the request's credentials must match those of | |
690 | * the calling process. | |
691 | * | |
692 | * Note: Should always be called with the Page Lock held! | |
693 | */ | |
694 | static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx, | |
695 | struct inode *inode, struct page *page, | |
696 | unsigned int offset, unsigned int bytes) | |
697 | { | |
698 | struct nfs_server *server = NFS_SERVER(inode); | |
699 | struct nfs_inode *nfsi = NFS_I(inode); | |
700 | struct nfs_page *req, *new = NULL; | |
701 | unsigned long rqend, end; | |
702 | ||
703 | end = offset + bytes; | |
704 | ||
705 | if (nfs_wait_on_write_congestion(page->mapping, server->flags & NFS_MOUNT_INTR)) | |
706 | return ERR_PTR(-ERESTARTSYS); | |
707 | for (;;) { | |
708 | /* Loop over all inode entries and see if we find | |
709 | * A request for the page we wish to update | |
710 | */ | |
711 | spin_lock(&nfsi->req_lock); | |
712 | req = _nfs_find_request(inode, page->index); | |
713 | if (req) { | |
714 | if (!nfs_lock_request_dontget(req)) { | |
715 | int error; | |
716 | spin_unlock(&nfsi->req_lock); | |
717 | error = nfs_wait_on_request(req); | |
718 | nfs_release_request(req); | |
1dd594b2 NB |
719 | if (error < 0) { |
720 | if (new) | |
721 | nfs_release_request(new); | |
1da177e4 | 722 | return ERR_PTR(error); |
1dd594b2 | 723 | } |
1da177e4 LT |
724 | continue; |
725 | } | |
726 | spin_unlock(&nfsi->req_lock); | |
727 | if (new) | |
728 | nfs_release_request(new); | |
729 | break; | |
730 | } | |
731 | ||
732 | if (new) { | |
733 | int error; | |
734 | nfs_lock_request_dontget(new); | |
735 | error = nfs_inode_add_request(inode, new); | |
736 | if (error) { | |
737 | spin_unlock(&nfsi->req_lock); | |
738 | nfs_unlock_request(new); | |
739 | return ERR_PTR(error); | |
740 | } | |
741 | spin_unlock(&nfsi->req_lock); | |
742 | nfs_mark_request_dirty(new); | |
743 | return new; | |
744 | } | |
745 | spin_unlock(&nfsi->req_lock); | |
746 | ||
747 | new = nfs_create_request(ctx, inode, page, offset, bytes); | |
748 | if (IS_ERR(new)) | |
749 | return new; | |
750 | } | |
751 | ||
752 | /* We have a request for our page. | |
753 | * If the creds don't match, or the | |
754 | * page addresses don't match, | |
755 | * tell the caller to wait on the conflicting | |
756 | * request. | |
757 | */ | |
758 | rqend = req->wb_offset + req->wb_bytes; | |
759 | if (req->wb_context != ctx | |
760 | || req->wb_page != page | |
761 | || !nfs_dirty_request(req) | |
762 | || offset > rqend || end < req->wb_offset) { | |
763 | nfs_unlock_request(req); | |
764 | return ERR_PTR(-EBUSY); | |
765 | } | |
766 | ||
767 | /* Okay, the request matches. Update the region */ | |
768 | if (offset < req->wb_offset) { | |
769 | req->wb_offset = offset; | |
770 | req->wb_pgbase = offset; | |
771 | req->wb_bytes = rqend - req->wb_offset; | |
772 | } | |
773 | ||
774 | if (end > rqend) | |
775 | req->wb_bytes = end - req->wb_offset; | |
776 | ||
777 | return req; | |
778 | } | |
779 | ||
780 | int nfs_flush_incompatible(struct file *file, struct page *page) | |
781 | { | |
782 | struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data; | |
783 | struct inode *inode = page->mapping->host; | |
784 | struct nfs_page *req; | |
785 | int status = 0; | |
786 | /* | |
787 | * Look for a request corresponding to this page. If there | |
788 | * is one, and it belongs to another file, we flush it out | |
789 | * before we try to copy anything into the page. Do this | |
790 | * due to the lack of an ACCESS-type call in NFSv2. | |
791 | * Also do the same if we find a request from an existing | |
792 | * dropped page. | |
793 | */ | |
794 | req = nfs_find_request(inode, page->index); | |
795 | if (req) { | |
796 | if (req->wb_page != page || ctx != req->wb_context) | |
797 | status = nfs_wb_page(inode, page); | |
798 | nfs_release_request(req); | |
799 | } | |
800 | return (status < 0) ? status : 0; | |
801 | } | |
802 | ||
803 | /* | |
804 | * Update and possibly write a cached page of an NFS file. | |
805 | * | |
806 | * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad | |
807 | * things with a page scheduled for an RPC call (e.g. invalidate it). | |
808 | */ | |
809 | int nfs_updatepage(struct file *file, struct page *page, | |
810 | unsigned int offset, unsigned int count) | |
811 | { | |
812 | struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data; | |
1da177e4 LT |
813 | struct inode *inode = page->mapping->host; |
814 | struct nfs_page *req; | |
815 | int status = 0; | |
816 | ||
91d5b470 CL |
817 | nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE); |
818 | ||
1da177e4 | 819 | dprintk("NFS: nfs_updatepage(%s/%s %d@%Ld)\n", |
0bbacc40 CL |
820 | file->f_dentry->d_parent->d_name.name, |
821 | file->f_dentry->d_name.name, count, | |
822 | (long long)(page_offset(page) +offset)); | |
1da177e4 LT |
823 | |
824 | if (IS_SYNC(inode)) { | |
825 | status = nfs_writepage_sync(ctx, inode, page, offset, count, 0); | |
826 | if (status > 0) { | |
827 | if (offset == 0 && status == PAGE_CACHE_SIZE) | |
828 | SetPageUptodate(page); | |
829 | return 0; | |
830 | } | |
831 | return status; | |
832 | } | |
833 | ||
834 | /* If we're not using byte range locks, and we know the page | |
835 | * is entirely in cache, it may be more efficient to avoid | |
836 | * fragmenting write requests. | |
837 | */ | |
ab0a3dbe | 838 | if (PageUptodate(page) && inode->i_flock == NULL && !(file->f_mode & O_SYNC)) { |
1da177e4 LT |
839 | loff_t end_offs = i_size_read(inode) - 1; |
840 | unsigned long end_index = end_offs >> PAGE_CACHE_SHIFT; | |
841 | ||
842 | count += offset; | |
843 | offset = 0; | |
844 | if (unlikely(end_offs < 0)) { | |
845 | /* Do nothing */ | |
846 | } else if (page->index == end_index) { | |
847 | unsigned int pglen; | |
848 | pglen = (unsigned int)(end_offs & (PAGE_CACHE_SIZE-1)) + 1; | |
849 | if (count < pglen) | |
850 | count = pglen; | |
851 | } else if (page->index < end_index) | |
852 | count = PAGE_CACHE_SIZE; | |
853 | } | |
854 | ||
855 | /* | |
856 | * Try to find an NFS request corresponding to this page | |
857 | * and update it. | |
858 | * If the existing request cannot be updated, we must flush | |
859 | * it out now. | |
860 | */ | |
861 | do { | |
862 | req = nfs_update_request(ctx, inode, page, offset, count); | |
863 | status = (IS_ERR(req)) ? PTR_ERR(req) : 0; | |
864 | if (status != -EBUSY) | |
865 | break; | |
866 | /* Request could not be updated. Flush it out and try again */ | |
867 | status = nfs_wb_page(inode, page); | |
868 | } while (status >= 0); | |
869 | if (status < 0) | |
870 | goto done; | |
871 | ||
872 | status = 0; | |
873 | ||
874 | /* Update file length */ | |
875 | nfs_grow_file(page, offset, count); | |
876 | /* Set the PG_uptodate flag? */ | |
877 | nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes); | |
878 | nfs_unlock_request(req); | |
879 | done: | |
880 | dprintk("NFS: nfs_updatepage returns %d (isize %Ld)\n", | |
881 | status, (long long)i_size_read(inode)); | |
882 | if (status < 0) | |
883 | ClearPageUptodate(page); | |
884 | return status; | |
885 | } | |
886 | ||
887 | static void nfs_writepage_release(struct nfs_page *req) | |
888 | { | |
889 | end_page_writeback(req->wb_page); | |
890 | ||
891 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
892 | if (!PageError(req->wb_page)) { | |
893 | if (NFS_NEED_RESCHED(req)) { | |
894 | nfs_mark_request_dirty(req); | |
895 | goto out; | |
896 | } else if (NFS_NEED_COMMIT(req)) { | |
897 | nfs_mark_request_commit(req); | |
898 | goto out; | |
899 | } | |
900 | } | |
901 | nfs_inode_remove_request(req); | |
902 | ||
903 | out: | |
904 | nfs_clear_commit(req); | |
905 | nfs_clear_reschedule(req); | |
906 | #else | |
907 | nfs_inode_remove_request(req); | |
908 | #endif | |
c6a556b8 | 909 | nfs_clear_page_writeback(req); |
1da177e4 LT |
910 | } |
911 | ||
912 | static inline int flush_task_priority(int how) | |
913 | { | |
914 | switch (how & (FLUSH_HIGHPRI|FLUSH_LOWPRI)) { | |
915 | case FLUSH_HIGHPRI: | |
916 | return RPC_PRIORITY_HIGH; | |
917 | case FLUSH_LOWPRI: | |
918 | return RPC_PRIORITY_LOW; | |
919 | } | |
920 | return RPC_PRIORITY_NORMAL; | |
921 | } | |
922 | ||
923 | /* | |
924 | * Set up the argument/result storage required for the RPC call. | |
925 | */ | |
926 | static void nfs_write_rpcsetup(struct nfs_page *req, | |
927 | struct nfs_write_data *data, | |
788e7a89 | 928 | const struct rpc_call_ops *call_ops, |
1da177e4 LT |
929 | unsigned int count, unsigned int offset, |
930 | int how) | |
931 | { | |
1da177e4 | 932 | struct inode *inode; |
788e7a89 | 933 | int flags; |
1da177e4 LT |
934 | |
935 | /* Set up the RPC argument and reply structs | |
936 | * NB: take care not to mess about with data->commit et al. */ | |
937 | ||
938 | data->req = req; | |
939 | data->inode = inode = req->wb_context->dentry->d_inode; | |
940 | data->cred = req->wb_context->cred; | |
941 | ||
942 | data->args.fh = NFS_FH(inode); | |
943 | data->args.offset = req_offset(req) + offset; | |
944 | data->args.pgbase = req->wb_pgbase + offset; | |
945 | data->args.pages = data->pagevec; | |
946 | data->args.count = count; | |
947 | data->args.context = req->wb_context; | |
948 | ||
949 | data->res.fattr = &data->fattr; | |
950 | data->res.count = count; | |
951 | data->res.verf = &data->verf; | |
0e574af1 | 952 | nfs_fattr_init(&data->fattr); |
1da177e4 | 953 | |
788e7a89 TM |
954 | /* Set up the initial task struct. */ |
955 | flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC; | |
956 | rpc_init_task(&data->task, NFS_CLIENT(inode), flags, call_ops, data); | |
1da177e4 LT |
957 | NFS_PROTO(inode)->write_setup(data, how); |
958 | ||
959 | data->task.tk_priority = flush_task_priority(how); | |
960 | data->task.tk_cookie = (unsigned long)inode; | |
1da177e4 LT |
961 | |
962 | dprintk("NFS: %4d initiated write call (req %s/%Ld, %u bytes @ offset %Lu)\n", | |
0bbacc40 | 963 | data->task.tk_pid, |
1da177e4 LT |
964 | inode->i_sb->s_id, |
965 | (long long)NFS_FILEID(inode), | |
966 | count, | |
967 | (unsigned long long)data->args.offset); | |
968 | } | |
969 | ||
970 | static void nfs_execute_write(struct nfs_write_data *data) | |
971 | { | |
972 | struct rpc_clnt *clnt = NFS_CLIENT(data->inode); | |
973 | sigset_t oldset; | |
974 | ||
975 | rpc_clnt_sigmask(clnt, &oldset); | |
976 | lock_kernel(); | |
977 | rpc_execute(&data->task); | |
978 | unlock_kernel(); | |
979 | rpc_clnt_sigunmask(clnt, &oldset); | |
980 | } | |
981 | ||
982 | /* | |
983 | * Generate multiple small requests to write out a single | |
984 | * contiguous dirty area on one page. | |
985 | */ | |
7d46a49f | 986 | static int nfs_flush_multi(struct inode *inode, struct list_head *head, int how) |
1da177e4 LT |
987 | { |
988 | struct nfs_page *req = nfs_list_entry(head->next); | |
989 | struct page *page = req->wb_page; | |
990 | struct nfs_write_data *data; | |
991 | unsigned int wsize = NFS_SERVER(inode)->wsize; | |
992 | unsigned int nbytes, offset; | |
993 | int requests = 0; | |
994 | LIST_HEAD(list); | |
995 | ||
996 | nfs_list_remove_request(req); | |
997 | ||
998 | nbytes = req->wb_bytes; | |
999 | for (;;) { | |
40859d7e | 1000 | data = nfs_writedata_alloc(1); |
1da177e4 LT |
1001 | if (!data) |
1002 | goto out_bad; | |
1003 | list_add(&data->pages, &list); | |
1004 | requests++; | |
1005 | if (nbytes <= wsize) | |
1006 | break; | |
1007 | nbytes -= wsize; | |
1008 | } | |
1009 | atomic_set(&req->wb_complete, requests); | |
1010 | ||
1011 | ClearPageError(page); | |
bb713d6d | 1012 | set_page_writeback(page); |
1da177e4 LT |
1013 | offset = 0; |
1014 | nbytes = req->wb_bytes; | |
1015 | do { | |
1016 | data = list_entry(list.next, struct nfs_write_data, pages); | |
1017 | list_del_init(&data->pages); | |
1018 | ||
1019 | data->pagevec[0] = page; | |
1da177e4 LT |
1020 | |
1021 | if (nbytes > wsize) { | |
788e7a89 TM |
1022 | nfs_write_rpcsetup(req, data, &nfs_write_partial_ops, |
1023 | wsize, offset, how); | |
1da177e4 LT |
1024 | offset += wsize; |
1025 | nbytes -= wsize; | |
1026 | } else { | |
788e7a89 TM |
1027 | nfs_write_rpcsetup(req, data, &nfs_write_partial_ops, |
1028 | nbytes, offset, how); | |
1da177e4 LT |
1029 | nbytes = 0; |
1030 | } | |
1031 | nfs_execute_write(data); | |
1032 | } while (nbytes != 0); | |
1033 | ||
1034 | return 0; | |
1035 | ||
1036 | out_bad: | |
1037 | while (!list_empty(&list)) { | |
1038 | data = list_entry(list.next, struct nfs_write_data, pages); | |
1039 | list_del(&data->pages); | |
1040 | nfs_writedata_free(data); | |
1041 | } | |
1042 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1043 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1044 | return -ENOMEM; |
1045 | } | |
1046 | ||
1047 | /* | |
1048 | * Create an RPC task for the given write request and kick it. | |
1049 | * The page must have been locked by the caller. | |
1050 | * | |
1051 | * It may happen that the page we're passed is not marked dirty. | |
1052 | * This is the case if nfs_updatepage detects a conflicting request | |
1053 | * that has been written but not committed. | |
1054 | */ | |
7d46a49f | 1055 | static int nfs_flush_one(struct inode *inode, struct list_head *head, int how) |
1da177e4 LT |
1056 | { |
1057 | struct nfs_page *req; | |
1058 | struct page **pages; | |
1059 | struct nfs_write_data *data; | |
1060 | unsigned int count; | |
1061 | ||
40859d7e | 1062 | data = nfs_writedata_alloc(NFS_SERVER(inode)->wpages); |
1da177e4 LT |
1063 | if (!data) |
1064 | goto out_bad; | |
1065 | ||
1066 | pages = data->pagevec; | |
1067 | count = 0; | |
1068 | while (!list_empty(head)) { | |
1069 | req = nfs_list_entry(head->next); | |
1070 | nfs_list_remove_request(req); | |
1071 | nfs_list_add_request(req, &data->pages); | |
1072 | ClearPageError(req->wb_page); | |
bb713d6d | 1073 | set_page_writeback(req->wb_page); |
1da177e4 LT |
1074 | *pages++ = req->wb_page; |
1075 | count += req->wb_bytes; | |
1076 | } | |
1077 | req = nfs_list_entry(data->pages.next); | |
1078 | ||
1da177e4 | 1079 | /* Set up the argument struct */ |
788e7a89 | 1080 | nfs_write_rpcsetup(req, data, &nfs_write_full_ops, count, 0, how); |
1da177e4 LT |
1081 | |
1082 | nfs_execute_write(data); | |
1083 | return 0; | |
1084 | out_bad: | |
1085 | while (!list_empty(head)) { | |
1086 | struct nfs_page *req = nfs_list_entry(head->next); | |
1087 | nfs_list_remove_request(req); | |
1088 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1089 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1090 | } |
1091 | return -ENOMEM; | |
1092 | } | |
1093 | ||
7d46a49f | 1094 | static int nfs_flush_list(struct inode *inode, struct list_head *head, int npages, int how) |
1da177e4 LT |
1095 | { |
1096 | LIST_HEAD(one_request); | |
7d46a49f TM |
1097 | int (*flush_one)(struct inode *, struct list_head *, int); |
1098 | struct nfs_page *req; | |
1099 | int wpages = NFS_SERVER(inode)->wpages; | |
1100 | int wsize = NFS_SERVER(inode)->wsize; | |
1101 | int error; | |
1da177e4 | 1102 | |
7d46a49f TM |
1103 | flush_one = nfs_flush_one; |
1104 | if (wsize < PAGE_CACHE_SIZE) | |
1105 | flush_one = nfs_flush_multi; | |
1106 | /* For single writes, FLUSH_STABLE is more efficient */ | |
1107 | if (npages <= wpages && npages == NFS_I(inode)->npages | |
1108 | && nfs_list_entry(head->next)->wb_bytes <= wsize) | |
1109 | how |= FLUSH_STABLE; | |
1110 | ||
1111 | do { | |
1112 | nfs_coalesce_requests(head, &one_request, wpages); | |
1da177e4 | 1113 | req = nfs_list_entry(one_request.next); |
7d46a49f | 1114 | error = flush_one(inode, &one_request, how); |
1da177e4 | 1115 | if (error < 0) |
7d46a49f TM |
1116 | goto out_err; |
1117 | } while (!list_empty(head)); | |
1118 | return 0; | |
1119 | out_err: | |
1da177e4 LT |
1120 | while (!list_empty(head)) { |
1121 | req = nfs_list_entry(head->next); | |
1122 | nfs_list_remove_request(req); | |
1123 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1124 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1125 | } |
1126 | return error; | |
1127 | } | |
1128 | ||
1129 | /* | |
1130 | * Handle a write reply that flushed part of a page. | |
1131 | */ | |
788e7a89 | 1132 | static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata) |
1da177e4 | 1133 | { |
788e7a89 | 1134 | struct nfs_write_data *data = calldata; |
1da177e4 LT |
1135 | struct nfs_page *req = data->req; |
1136 | struct page *page = req->wb_page; | |
1137 | ||
1138 | dprintk("NFS: write (%s/%Ld %d@%Ld)", | |
1139 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1140 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1141 | req->wb_bytes, | |
1142 | (long long)req_offset(req)); | |
1143 | ||
788e7a89 TM |
1144 | if (nfs_writeback_done(task, data) != 0) |
1145 | return; | |
1146 | ||
1147 | if (task->tk_status < 0) { | |
1da177e4 LT |
1148 | ClearPageUptodate(page); |
1149 | SetPageError(page); | |
788e7a89 TM |
1150 | req->wb_context->error = task->tk_status; |
1151 | dprintk(", error = %d\n", task->tk_status); | |
1da177e4 LT |
1152 | } else { |
1153 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1154 | if (data->verf.committed < NFS_FILE_SYNC) { | |
1155 | if (!NFS_NEED_COMMIT(req)) { | |
1156 | nfs_defer_commit(req); | |
1157 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1158 | dprintk(" defer commit\n"); | |
1159 | } else if (memcmp(&req->wb_verf, &data->verf, sizeof(req->wb_verf))) { | |
1160 | nfs_defer_reschedule(req); | |
1161 | dprintk(" server reboot detected\n"); | |
1162 | } | |
1163 | } else | |
1164 | #endif | |
1165 | dprintk(" OK\n"); | |
1166 | } | |
1167 | ||
1168 | if (atomic_dec_and_test(&req->wb_complete)) | |
1169 | nfs_writepage_release(req); | |
1170 | } | |
1171 | ||
788e7a89 TM |
1172 | static const struct rpc_call_ops nfs_write_partial_ops = { |
1173 | .rpc_call_done = nfs_writeback_done_partial, | |
1174 | .rpc_release = nfs_writedata_release, | |
1175 | }; | |
1176 | ||
1da177e4 LT |
1177 | /* |
1178 | * Handle a write reply that flushes a whole page. | |
1179 | * | |
1180 | * FIXME: There is an inherent race with invalidate_inode_pages and | |
1181 | * writebacks since the page->count is kept > 1 for as long | |
1182 | * as the page has a write request pending. | |
1183 | */ | |
788e7a89 | 1184 | static void nfs_writeback_done_full(struct rpc_task *task, void *calldata) |
1da177e4 | 1185 | { |
788e7a89 | 1186 | struct nfs_write_data *data = calldata; |
1da177e4 LT |
1187 | struct nfs_page *req; |
1188 | struct page *page; | |
1189 | ||
788e7a89 TM |
1190 | if (nfs_writeback_done(task, data) != 0) |
1191 | return; | |
1192 | ||
1da177e4 LT |
1193 | /* Update attributes as result of writeback. */ |
1194 | while (!list_empty(&data->pages)) { | |
1195 | req = nfs_list_entry(data->pages.next); | |
1196 | nfs_list_remove_request(req); | |
1197 | page = req->wb_page; | |
1198 | ||
1199 | dprintk("NFS: write (%s/%Ld %d@%Ld)", | |
1200 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1201 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1202 | req->wb_bytes, | |
1203 | (long long)req_offset(req)); | |
1204 | ||
788e7a89 | 1205 | if (task->tk_status < 0) { |
1da177e4 LT |
1206 | ClearPageUptodate(page); |
1207 | SetPageError(page); | |
788e7a89 | 1208 | req->wb_context->error = task->tk_status; |
1da177e4 LT |
1209 | end_page_writeback(page); |
1210 | nfs_inode_remove_request(req); | |
788e7a89 | 1211 | dprintk(", error = %d\n", task->tk_status); |
1da177e4 LT |
1212 | goto next; |
1213 | } | |
1214 | end_page_writeback(page); | |
1215 | ||
1216 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1217 | if (data->args.stable != NFS_UNSTABLE || data->verf.committed == NFS_FILE_SYNC) { | |
1218 | nfs_inode_remove_request(req); | |
1219 | dprintk(" OK\n"); | |
1220 | goto next; | |
1221 | } | |
1222 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1223 | nfs_mark_request_commit(req); | |
1224 | dprintk(" marked for commit\n"); | |
1225 | #else | |
1226 | nfs_inode_remove_request(req); | |
1227 | #endif | |
1228 | next: | |
c6a556b8 | 1229 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1230 | } |
1231 | } | |
1232 | ||
788e7a89 TM |
1233 | static const struct rpc_call_ops nfs_write_full_ops = { |
1234 | .rpc_call_done = nfs_writeback_done_full, | |
1235 | .rpc_release = nfs_writedata_release, | |
1236 | }; | |
1237 | ||
1238 | ||
1da177e4 LT |
1239 | /* |
1240 | * This function is called when the WRITE call is complete. | |
1241 | */ | |
462d5b32 | 1242 | int nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data) |
1da177e4 | 1243 | { |
1da177e4 LT |
1244 | struct nfs_writeargs *argp = &data->args; |
1245 | struct nfs_writeres *resp = &data->res; | |
788e7a89 | 1246 | int status; |
1da177e4 LT |
1247 | |
1248 | dprintk("NFS: %4d nfs_writeback_done (status %d)\n", | |
1249 | task->tk_pid, task->tk_status); | |
1250 | ||
788e7a89 TM |
1251 | /* Call the NFS version-specific code */ |
1252 | status = NFS_PROTO(data->inode)->write_done(task, data); | |
1253 | if (status != 0) | |
1254 | return status; | |
91d5b470 CL |
1255 | nfs_add_stats(data->inode, NFSIOS_SERVERWRITTENBYTES, resp->count); |
1256 | ||
1da177e4 LT |
1257 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) |
1258 | if (resp->verf->committed < argp->stable && task->tk_status >= 0) { | |
1259 | /* We tried a write call, but the server did not | |
1260 | * commit data to stable storage even though we | |
1261 | * requested it. | |
1262 | * Note: There is a known bug in Tru64 < 5.0 in which | |
1263 | * the server reports NFS_DATA_SYNC, but performs | |
1264 | * NFS_FILE_SYNC. We therefore implement this checking | |
1265 | * as a dprintk() in order to avoid filling syslog. | |
1266 | */ | |
1267 | static unsigned long complain; | |
1268 | ||
1269 | if (time_before(complain, jiffies)) { | |
1270 | dprintk("NFS: faulty NFS server %s:" | |
1271 | " (committed = %d) != (stable = %d)\n", | |
1272 | NFS_SERVER(data->inode)->hostname, | |
1273 | resp->verf->committed, argp->stable); | |
1274 | complain = jiffies + 300 * HZ; | |
1275 | } | |
1276 | } | |
1277 | #endif | |
1278 | /* Is this a short write? */ | |
1279 | if (task->tk_status >= 0 && resp->count < argp->count) { | |
1280 | static unsigned long complain; | |
1281 | ||
91d5b470 CL |
1282 | nfs_inc_stats(data->inode, NFSIOS_SHORTWRITE); |
1283 | ||
1da177e4 LT |
1284 | /* Has the server at least made some progress? */ |
1285 | if (resp->count != 0) { | |
1286 | /* Was this an NFSv2 write or an NFSv3 stable write? */ | |
1287 | if (resp->verf->committed != NFS_UNSTABLE) { | |
1288 | /* Resend from where the server left off */ | |
1289 | argp->offset += resp->count; | |
1290 | argp->pgbase += resp->count; | |
1291 | argp->count -= resp->count; | |
1292 | } else { | |
1293 | /* Resend as a stable write in order to avoid | |
1294 | * headaches in the case of a server crash. | |
1295 | */ | |
1296 | argp->stable = NFS_FILE_SYNC; | |
1297 | } | |
1298 | rpc_restart_call(task); | |
788e7a89 | 1299 | return -EAGAIN; |
1da177e4 LT |
1300 | } |
1301 | if (time_before(complain, jiffies)) { | |
1302 | printk(KERN_WARNING | |
1303 | "NFS: Server wrote zero bytes, expected %u.\n", | |
1304 | argp->count); | |
1305 | complain = jiffies + 300 * HZ; | |
1306 | } | |
1307 | /* Can't do anything about it except throw an error. */ | |
1308 | task->tk_status = -EIO; | |
1309 | } | |
788e7a89 | 1310 | return 0; |
1da177e4 LT |
1311 | } |
1312 | ||
1313 | ||
1314 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
963d8fe5 | 1315 | void nfs_commit_release(void *wdata) |
1da177e4 | 1316 | { |
1da177e4 LT |
1317 | nfs_commit_free(wdata); |
1318 | } | |
1319 | ||
1320 | /* | |
1321 | * Set up the argument/result storage required for the RPC call. | |
1322 | */ | |
1323 | static void nfs_commit_rpcsetup(struct list_head *head, | |
788e7a89 TM |
1324 | struct nfs_write_data *data, |
1325 | int how) | |
1da177e4 | 1326 | { |
3da28eb1 | 1327 | struct nfs_page *first; |
1da177e4 | 1328 | struct inode *inode; |
788e7a89 | 1329 | int flags; |
1da177e4 LT |
1330 | |
1331 | /* Set up the RPC argument and reply structs | |
1332 | * NB: take care not to mess about with data->commit et al. */ | |
1333 | ||
1334 | list_splice_init(head, &data->pages); | |
1335 | first = nfs_list_entry(data->pages.next); | |
1da177e4 LT |
1336 | inode = first->wb_context->dentry->d_inode; |
1337 | ||
1da177e4 LT |
1338 | data->inode = inode; |
1339 | data->cred = first->wb_context->cred; | |
1340 | ||
1341 | data->args.fh = NFS_FH(data->inode); | |
3da28eb1 TM |
1342 | /* Note: we always request a commit of the entire inode */ |
1343 | data->args.offset = 0; | |
1344 | data->args.count = 0; | |
1345 | data->res.count = 0; | |
1da177e4 LT |
1346 | data->res.fattr = &data->fattr; |
1347 | data->res.verf = &data->verf; | |
0e574af1 | 1348 | nfs_fattr_init(&data->fattr); |
788e7a89 TM |
1349 | |
1350 | /* Set up the initial task struct. */ | |
1351 | flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC; | |
1352 | rpc_init_task(&data->task, NFS_CLIENT(inode), flags, &nfs_commit_ops, data); | |
1da177e4 LT |
1353 | NFS_PROTO(inode)->commit_setup(data, how); |
1354 | ||
1355 | data->task.tk_priority = flush_task_priority(how); | |
1356 | data->task.tk_cookie = (unsigned long)inode; | |
1da177e4 | 1357 | |
0bbacc40 | 1358 | dprintk("NFS: %4d initiated commit call\n", data->task.tk_pid); |
1da177e4 LT |
1359 | } |
1360 | ||
1361 | /* | |
1362 | * Commit dirty pages | |
1363 | */ | |
1364 | static int | |
40859d7e | 1365 | nfs_commit_list(struct inode *inode, struct list_head *head, int how) |
1da177e4 LT |
1366 | { |
1367 | struct nfs_write_data *data; | |
1368 | struct nfs_page *req; | |
1369 | ||
40859d7e | 1370 | data = nfs_commit_alloc(NFS_SERVER(inode)->wpages); |
1da177e4 LT |
1371 | |
1372 | if (!data) | |
1373 | goto out_bad; | |
1374 | ||
1375 | /* Set up the argument struct */ | |
1376 | nfs_commit_rpcsetup(head, data, how); | |
1377 | ||
1378 | nfs_execute_write(data); | |
1379 | return 0; | |
1380 | out_bad: | |
1381 | while (!list_empty(head)) { | |
1382 | req = nfs_list_entry(head->next); | |
1383 | nfs_list_remove_request(req); | |
1384 | nfs_mark_request_commit(req); | |
c6a556b8 | 1385 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1386 | } |
1387 | return -ENOMEM; | |
1388 | } | |
1389 | ||
1390 | /* | |
1391 | * COMMIT call returned | |
1392 | */ | |
788e7a89 | 1393 | static void nfs_commit_done(struct rpc_task *task, void *calldata) |
1da177e4 | 1394 | { |
963d8fe5 | 1395 | struct nfs_write_data *data = calldata; |
1da177e4 LT |
1396 | struct nfs_page *req; |
1397 | int res = 0; | |
1398 | ||
1399 | dprintk("NFS: %4d nfs_commit_done (status %d)\n", | |
1400 | task->tk_pid, task->tk_status); | |
1401 | ||
788e7a89 TM |
1402 | /* Call the NFS version-specific code */ |
1403 | if (NFS_PROTO(data->inode)->commit_done(task, data) != 0) | |
1404 | return; | |
1405 | ||
1da177e4 LT |
1406 | while (!list_empty(&data->pages)) { |
1407 | req = nfs_list_entry(data->pages.next); | |
1408 | nfs_list_remove_request(req); | |
1409 | ||
1410 | dprintk("NFS: commit (%s/%Ld %d@%Ld)", | |
1411 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1412 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1413 | req->wb_bytes, | |
1414 | (long long)req_offset(req)); | |
1415 | if (task->tk_status < 0) { | |
1416 | req->wb_context->error = task->tk_status; | |
1417 | nfs_inode_remove_request(req); | |
1418 | dprintk(", error = %d\n", task->tk_status); | |
1419 | goto next; | |
1420 | } | |
1421 | ||
1422 | /* Okay, COMMIT succeeded, apparently. Check the verifier | |
1423 | * returned by the server against all stored verfs. */ | |
1424 | if (!memcmp(req->wb_verf.verifier, data->verf.verifier, sizeof(data->verf.verifier))) { | |
1425 | /* We have a match */ | |
1426 | nfs_inode_remove_request(req); | |
1427 | dprintk(" OK\n"); | |
1428 | goto next; | |
1429 | } | |
1430 | /* We have a mismatch. Write the page again */ | |
1431 | dprintk(" mismatch\n"); | |
1432 | nfs_mark_request_dirty(req); | |
1433 | next: | |
c6a556b8 | 1434 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1435 | res++; |
1436 | } | |
1437 | sub_page_state(nr_unstable,res); | |
1438 | } | |
788e7a89 TM |
1439 | |
1440 | static const struct rpc_call_ops nfs_commit_ops = { | |
1441 | .rpc_call_done = nfs_commit_done, | |
1442 | .rpc_release = nfs_commit_release, | |
1443 | }; | |
c42de9dd TM |
1444 | #else |
1445 | static inline int nfs_commit_list(struct inode *inode, struct list_head *head, int how) | |
1446 | { | |
1447 | return 0; | |
1448 | } | |
1da177e4 LT |
1449 | #endif |
1450 | ||
1451 | static int nfs_flush_inode(struct inode *inode, unsigned long idx_start, | |
1452 | unsigned int npages, int how) | |
1453 | { | |
1454 | struct nfs_inode *nfsi = NFS_I(inode); | |
1455 | LIST_HEAD(head); | |
7d46a49f | 1456 | int res; |
1da177e4 LT |
1457 | |
1458 | spin_lock(&nfsi->req_lock); | |
1459 | res = nfs_scan_dirty(inode, &head, idx_start, npages); | |
1460 | spin_unlock(&nfsi->req_lock); | |
ab0a3dbe | 1461 | if (res) { |
7d46a49f TM |
1462 | int error = nfs_flush_list(inode, &head, res, how); |
1463 | if (error < 0) | |
1464 | return error; | |
ab0a3dbe | 1465 | } |
1da177e4 LT |
1466 | return res; |
1467 | } | |
1468 | ||
1469 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
3da28eb1 | 1470 | int nfs_commit_inode(struct inode *inode, int how) |
1da177e4 LT |
1471 | { |
1472 | struct nfs_inode *nfsi = NFS_I(inode); | |
1473 | LIST_HEAD(head); | |
7d46a49f | 1474 | int res; |
1da177e4 LT |
1475 | |
1476 | spin_lock(&nfsi->req_lock); | |
3da28eb1 TM |
1477 | res = nfs_scan_commit(inode, &head, 0, 0); |
1478 | spin_unlock(&nfsi->req_lock); | |
1da177e4 | 1479 | if (res) { |
7d46a49f | 1480 | int error = nfs_commit_list(inode, &head, how); |
3da28eb1 TM |
1481 | if (error < 0) |
1482 | return error; | |
1483 | } | |
1da177e4 LT |
1484 | return res; |
1485 | } | |
1486 | #endif | |
1487 | ||
c42de9dd TM |
1488 | int nfs_sync_inode_wait(struct inode *inode, unsigned long idx_start, |
1489 | unsigned int npages, int how) | |
1da177e4 | 1490 | { |
c42de9dd TM |
1491 | struct nfs_inode *nfsi = NFS_I(inode); |
1492 | LIST_HEAD(head); | |
70b9ecbd | 1493 | int nocommit = how & FLUSH_NOCOMMIT; |
c42de9dd | 1494 | int pages, ret; |
1da177e4 | 1495 | |
c42de9dd TM |
1496 | how &= ~FLUSH_NOCOMMIT; |
1497 | spin_lock(&nfsi->req_lock); | |
1da177e4 | 1498 | do { |
c42de9dd TM |
1499 | ret = nfs_wait_on_requests_locked(inode, idx_start, npages); |
1500 | if (ret != 0) | |
70b9ecbd | 1501 | continue; |
c42de9dd TM |
1502 | pages = nfs_scan_dirty(inode, &head, idx_start, npages); |
1503 | if (pages != 0) { | |
1504 | spin_unlock(&nfsi->req_lock); | |
d2ccddf0 TM |
1505 | if (how & FLUSH_INVALIDATE) |
1506 | nfs_cancel_requests(&head); | |
1507 | else | |
1508 | ret = nfs_flush_list(inode, &head, pages, how); | |
c42de9dd TM |
1509 | spin_lock(&nfsi->req_lock); |
1510 | continue; | |
1511 | } | |
1512 | if (nocommit) | |
1513 | break; | |
d2ccddf0 | 1514 | pages = nfs_scan_commit(inode, &head, idx_start, npages); |
c42de9dd TM |
1515 | if (pages == 0) |
1516 | break; | |
d2ccddf0 TM |
1517 | if (how & FLUSH_INVALIDATE) { |
1518 | spin_unlock(&nfsi->req_lock); | |
1519 | nfs_cancel_requests(&head); | |
1520 | spin_lock(&nfsi->req_lock); | |
1521 | continue; | |
1522 | } | |
1523 | pages += nfs_scan_commit(inode, &head, 0, 0); | |
c42de9dd TM |
1524 | spin_unlock(&nfsi->req_lock); |
1525 | ret = nfs_commit_list(inode, &head, how); | |
1526 | spin_lock(&nfsi->req_lock); | |
1527 | } while (ret >= 0); | |
1528 | spin_unlock(&nfsi->req_lock); | |
1529 | return ret; | |
1da177e4 LT |
1530 | } |
1531 | ||
1532 | int nfs_init_writepagecache(void) | |
1533 | { | |
1534 | nfs_wdata_cachep = kmem_cache_create("nfs_write_data", | |
1535 | sizeof(struct nfs_write_data), | |
1536 | 0, SLAB_HWCACHE_ALIGN, | |
1537 | NULL, NULL); | |
1538 | if (nfs_wdata_cachep == NULL) | |
1539 | return -ENOMEM; | |
1540 | ||
93d2341c MD |
1541 | nfs_wdata_mempool = mempool_create_slab_pool(MIN_POOL_WRITE, |
1542 | nfs_wdata_cachep); | |
1da177e4 LT |
1543 | if (nfs_wdata_mempool == NULL) |
1544 | return -ENOMEM; | |
1545 | ||
93d2341c MD |
1546 | nfs_commit_mempool = mempool_create_slab_pool(MIN_POOL_COMMIT, |
1547 | nfs_wdata_cachep); | |
1da177e4 LT |
1548 | if (nfs_commit_mempool == NULL) |
1549 | return -ENOMEM; | |
1550 | ||
1551 | return 0; | |
1552 | } | |
1553 | ||
1554 | void nfs_destroy_writepagecache(void) | |
1555 | { | |
1556 | mempool_destroy(nfs_commit_mempool); | |
1557 | mempool_destroy(nfs_wdata_mempool); | |
1558 | if (kmem_cache_destroy(nfs_wdata_cachep)) | |
1559 | printk(KERN_INFO "nfs_write_data: not all structures were freed\n"); | |
1560 | } | |
1561 |