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 | ||
1da177e4 LT |
49 | #include <linux/types.h> |
50 | #include <linux/slab.h> | |
51 | #include <linux/mm.h> | |
52 | #include <linux/pagemap.h> | |
53 | #include <linux/file.h> | |
54 | #include <linux/mpage.h> | |
55 | #include <linux/writeback.h> | |
56 | ||
57 | #include <linux/sunrpc/clnt.h> | |
58 | #include <linux/nfs_fs.h> | |
59 | #include <linux/nfs_mount.h> | |
60 | #include <linux/nfs_page.h> | |
61 | #include <asm/uaccess.h> | |
62 | #include <linux/smp_lock.h> | |
63 | ||
64 | #include "delegation.h" | |
91d5b470 | 65 | #include "iostat.h" |
1da177e4 LT |
66 | |
67 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE | |
68 | ||
69 | #define MIN_POOL_WRITE (32) | |
70 | #define MIN_POOL_COMMIT (4) | |
71 | ||
72 | /* | |
73 | * Local function declarations | |
74 | */ | |
75 | static struct nfs_page * nfs_update_request(struct nfs_open_context*, | |
76 | struct inode *, | |
77 | struct page *, | |
78 | unsigned int, unsigned int); | |
1da177e4 LT |
79 | static int nfs_wait_on_write_congestion(struct address_space *, int); |
80 | static int nfs_wait_on_requests(struct inode *, unsigned long, unsigned int); | |
81 | static int nfs_flush_inode(struct inode *inode, unsigned long idx_start, | |
82 | unsigned int npages, int how); | |
788e7a89 TM |
83 | static const struct rpc_call_ops nfs_write_partial_ops; |
84 | static const struct rpc_call_ops nfs_write_full_ops; | |
85 | static const struct rpc_call_ops nfs_commit_ops; | |
1da177e4 LT |
86 | |
87 | static kmem_cache_t *nfs_wdata_cachep; | |
3feb2d49 | 88 | static mempool_t *nfs_wdata_mempool; |
1da177e4 LT |
89 | static mempool_t *nfs_commit_mempool; |
90 | ||
91 | static DECLARE_WAIT_QUEUE_HEAD(nfs_write_congestion); | |
92 | ||
e17b1fc4 | 93 | struct nfs_write_data *nfs_commit_alloc(unsigned int pagecount) |
1da177e4 LT |
94 | { |
95 | struct nfs_write_data *p = mempool_alloc(nfs_commit_mempool, SLAB_NOFS); | |
40859d7e | 96 | |
1da177e4 LT |
97 | if (p) { |
98 | memset(p, 0, sizeof(*p)); | |
99 | INIT_LIST_HEAD(&p->pages); | |
0d0b5cb3 CL |
100 | if (pagecount <= ARRAY_SIZE(p->page_array)) |
101 | p->pagevec = p->page_array; | |
40859d7e | 102 | else { |
0d0b5cb3 | 103 | p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_NOFS); |
bd647545 | 104 | if (!p->pagevec) { |
40859d7e CL |
105 | mempool_free(p, nfs_commit_mempool); |
106 | p = NULL; | |
107 | } | |
108 | } | |
1da177e4 LT |
109 | } |
110 | return p; | |
111 | } | |
112 | ||
e17b1fc4 | 113 | void nfs_commit_free(struct nfs_write_data *p) |
1da177e4 | 114 | { |
40859d7e CL |
115 | if (p && (p->pagevec != &p->page_array[0])) |
116 | kfree(p->pagevec); | |
1da177e4 LT |
117 | mempool_free(p, nfs_commit_mempool); |
118 | } | |
119 | ||
3feb2d49 TM |
120 | struct nfs_write_data *nfs_writedata_alloc(unsigned int pagecount) |
121 | { | |
122 | struct nfs_write_data *p = mempool_alloc(nfs_wdata_mempool, SLAB_NOFS); | |
123 | ||
124 | if (p) { | |
125 | memset(p, 0, sizeof(*p)); | |
126 | INIT_LIST_HEAD(&p->pages); | |
0d0b5cb3 CL |
127 | if (pagecount <= ARRAY_SIZE(p->page_array)) |
128 | p->pagevec = p->page_array; | |
3feb2d49 | 129 | else { |
0d0b5cb3 CL |
130 | p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_NOFS); |
131 | if (!p->pagevec) { | |
3feb2d49 TM |
132 | mempool_free(p, nfs_wdata_mempool); |
133 | p = NULL; | |
134 | } | |
135 | } | |
136 | } | |
137 | return p; | |
138 | } | |
139 | ||
140 | void nfs_writedata_free(struct nfs_write_data *p) | |
141 | { | |
142 | if (p && (p->pagevec != &p->page_array[0])) | |
143 | kfree(p->pagevec); | |
144 | mempool_free(p, nfs_wdata_mempool); | |
145 | } | |
146 | ||
963d8fe5 | 147 | void nfs_writedata_release(void *wdata) |
1da177e4 | 148 | { |
1da177e4 LT |
149 | nfs_writedata_free(wdata); |
150 | } | |
151 | ||
152 | /* Adjust the file length if we're writing beyond the end */ | |
153 | static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count) | |
154 | { | |
155 | struct inode *inode = page->mapping->host; | |
156 | loff_t end, i_size = i_size_read(inode); | |
157 | unsigned long end_index = (i_size - 1) >> PAGE_CACHE_SHIFT; | |
158 | ||
159 | if (i_size > 0 && page->index < end_index) | |
160 | return; | |
161 | end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + ((loff_t)offset+count); | |
162 | if (i_size >= end) | |
163 | return; | |
91d5b470 | 164 | nfs_inc_stats(inode, NFSIOS_EXTENDWRITE); |
1da177e4 LT |
165 | i_size_write(inode, end); |
166 | } | |
167 | ||
168 | /* We can set the PG_uptodate flag if we see that a write request | |
169 | * covers the full page. | |
170 | */ | |
171 | static void nfs_mark_uptodate(struct page *page, unsigned int base, unsigned int count) | |
172 | { | |
173 | loff_t end_offs; | |
174 | ||
175 | if (PageUptodate(page)) | |
176 | return; | |
177 | if (base != 0) | |
178 | return; | |
179 | if (count == PAGE_CACHE_SIZE) { | |
180 | SetPageUptodate(page); | |
181 | return; | |
182 | } | |
183 | ||
184 | end_offs = i_size_read(page->mapping->host) - 1; | |
185 | if (end_offs < 0) | |
186 | return; | |
187 | /* Is this the last page? */ | |
188 | if (page->index != (unsigned long)(end_offs >> PAGE_CACHE_SHIFT)) | |
189 | return; | |
190 | /* This is the last page: set PG_uptodate if we cover the entire | |
191 | * extent of the data, then zero the rest of the page. | |
192 | */ | |
193 | if (count == (unsigned int)(end_offs & (PAGE_CACHE_SIZE - 1)) + 1) { | |
194 | memclear_highpage_flush(page, count, PAGE_CACHE_SIZE - count); | |
195 | SetPageUptodate(page); | |
196 | } | |
197 | } | |
198 | ||
199 | /* | |
200 | * Write a page synchronously. | |
201 | * Offset is the data offset within the page. | |
202 | */ | |
203 | static int nfs_writepage_sync(struct nfs_open_context *ctx, struct inode *inode, | |
204 | struct page *page, unsigned int offset, unsigned int count, | |
205 | int how) | |
206 | { | |
207 | unsigned int wsize = NFS_SERVER(inode)->wsize; | |
208 | int result, written = 0; | |
209 | struct nfs_write_data *wdata; | |
210 | ||
40859d7e | 211 | wdata = nfs_writedata_alloc(1); |
1da177e4 LT |
212 | if (!wdata) |
213 | return -ENOMEM; | |
214 | ||
215 | wdata->flags = how; | |
216 | wdata->cred = ctx->cred; | |
217 | wdata->inode = inode; | |
218 | wdata->args.fh = NFS_FH(inode); | |
219 | wdata->args.context = ctx; | |
220 | wdata->args.pages = &page; | |
221 | wdata->args.stable = NFS_FILE_SYNC; | |
222 | wdata->args.pgbase = offset; | |
223 | wdata->args.count = wsize; | |
224 | wdata->res.fattr = &wdata->fattr; | |
225 | wdata->res.verf = &wdata->verf; | |
226 | ||
227 | dprintk("NFS: nfs_writepage_sync(%s/%Ld %d@%Ld)\n", | |
228 | inode->i_sb->s_id, | |
229 | (long long)NFS_FILEID(inode), | |
230 | count, (long long)(page_offset(page) + offset)); | |
231 | ||
bb713d6d | 232 | set_page_writeback(page); |
1da177e4 LT |
233 | nfs_begin_data_update(inode); |
234 | do { | |
235 | if (count < wsize) | |
236 | wdata->args.count = count; | |
237 | wdata->args.offset = page_offset(page) + wdata->args.pgbase; | |
238 | ||
239 | result = NFS_PROTO(inode)->write(wdata); | |
240 | ||
241 | if (result < 0) { | |
242 | /* Must mark the page invalid after I/O error */ | |
243 | ClearPageUptodate(page); | |
244 | goto io_error; | |
245 | } | |
246 | if (result < wdata->args.count) | |
247 | printk(KERN_WARNING "NFS: short write, count=%u, result=%d\n", | |
248 | wdata->args.count, result); | |
249 | ||
250 | wdata->args.offset += result; | |
251 | wdata->args.pgbase += result; | |
252 | written += result; | |
253 | count -= result; | |
91d5b470 | 254 | nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, result); |
1da177e4 LT |
255 | } while (count); |
256 | /* Update file length */ | |
257 | nfs_grow_file(page, offset, written); | |
258 | /* Set the PG_uptodate flag? */ | |
259 | nfs_mark_uptodate(page, offset, written); | |
260 | ||
261 | if (PageError(page)) | |
262 | ClearPageError(page); | |
263 | ||
264 | io_error: | |
951a143b | 265 | nfs_end_data_update(inode); |
bb713d6d | 266 | end_page_writeback(page); |
1da177e4 LT |
267 | nfs_writedata_free(wdata); |
268 | return written ? written : result; | |
269 | } | |
270 | ||
271 | static int nfs_writepage_async(struct nfs_open_context *ctx, | |
272 | struct inode *inode, struct page *page, | |
273 | unsigned int offset, unsigned int count) | |
274 | { | |
275 | struct nfs_page *req; | |
1da177e4 LT |
276 | |
277 | req = nfs_update_request(ctx, inode, page, offset, count); | |
abd3e641 TM |
278 | if (IS_ERR(req)) |
279 | return PTR_ERR(req); | |
1da177e4 LT |
280 | /* Update file length */ |
281 | nfs_grow_file(page, offset, count); | |
282 | /* Set the PG_uptodate flag? */ | |
283 | nfs_mark_uptodate(page, offset, count); | |
284 | nfs_unlock_request(req); | |
abd3e641 | 285 | return 0; |
1da177e4 LT |
286 | } |
287 | ||
288 | static int wb_priority(struct writeback_control *wbc) | |
289 | { | |
290 | if (wbc->for_reclaim) | |
291 | return FLUSH_HIGHPRI; | |
292 | if (wbc->for_kupdate) | |
293 | return FLUSH_LOWPRI; | |
294 | return 0; | |
295 | } | |
296 | ||
297 | /* | |
298 | * Write an mmapped page to the server. | |
299 | */ | |
300 | int nfs_writepage(struct page *page, struct writeback_control *wbc) | |
301 | { | |
302 | struct nfs_open_context *ctx; | |
303 | struct inode *inode = page->mapping->host; | |
304 | unsigned long end_index; | |
305 | unsigned offset = PAGE_CACHE_SIZE; | |
306 | loff_t i_size = i_size_read(inode); | |
307 | int inode_referenced = 0; | |
308 | int priority = wb_priority(wbc); | |
309 | int err; | |
310 | ||
91d5b470 CL |
311 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE); |
312 | nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1); | |
313 | ||
1da177e4 LT |
314 | /* |
315 | * Note: We need to ensure that we have a reference to the inode | |
316 | * if we are to do asynchronous writes. If not, waiting | |
317 | * in nfs_wait_on_request() may deadlock with clear_inode(). | |
318 | * | |
319 | * If igrab() fails here, then it is in any case safe to | |
320 | * call nfs_wb_page(), since there will be no pending writes. | |
321 | */ | |
322 | if (igrab(inode) != 0) | |
323 | inode_referenced = 1; | |
324 | end_index = i_size >> PAGE_CACHE_SHIFT; | |
325 | ||
326 | /* Ensure we've flushed out any previous writes */ | |
327 | nfs_wb_page_priority(inode, page, priority); | |
328 | ||
329 | /* easy case */ | |
330 | if (page->index < end_index) | |
331 | goto do_it; | |
332 | /* things got complicated... */ | |
333 | offset = i_size & (PAGE_CACHE_SIZE-1); | |
334 | ||
335 | /* OK, are we completely out? */ | |
336 | err = 0; /* potential race with truncate - ignore */ | |
337 | if (page->index >= end_index+1 || !offset) | |
338 | goto out; | |
339 | do_it: | |
d530838b | 340 | ctx = nfs_find_open_context(inode, NULL, FMODE_WRITE); |
1da177e4 LT |
341 | if (ctx == NULL) { |
342 | err = -EBADF; | |
343 | goto out; | |
344 | } | |
345 | lock_kernel(); | |
346 | if (!IS_SYNC(inode) && inode_referenced) { | |
347 | err = nfs_writepage_async(ctx, inode, page, 0, offset); | |
abd3e641 TM |
348 | if (!wbc->for_writepages) |
349 | nfs_flush_inode(inode, 0, 0, wb_priority(wbc)); | |
1da177e4 LT |
350 | } else { |
351 | err = nfs_writepage_sync(ctx, inode, page, 0, | |
352 | offset, priority); | |
353 | if (err >= 0) { | |
354 | if (err != offset) | |
355 | redirty_page_for_writepage(wbc, page); | |
356 | err = 0; | |
357 | } | |
358 | } | |
359 | unlock_kernel(); | |
360 | put_nfs_open_context(ctx); | |
361 | out: | |
362 | unlock_page(page); | |
363 | if (inode_referenced) | |
364 | iput(inode); | |
365 | return err; | |
366 | } | |
367 | ||
368 | /* | |
369 | * Note: causes nfs_update_request() to block on the assumption | |
370 | * that the writeback is generated due to memory pressure. | |
371 | */ | |
372 | int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc) | |
373 | { | |
374 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
375 | struct inode *inode = mapping->host; | |
376 | int err; | |
377 | ||
91d5b470 CL |
378 | nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES); |
379 | ||
1da177e4 LT |
380 | err = generic_writepages(mapping, wbc); |
381 | if (err) | |
382 | return err; | |
383 | while (test_and_set_bit(BDI_write_congested, &bdi->state) != 0) { | |
384 | if (wbc->nonblocking) | |
385 | return 0; | |
386 | nfs_wait_on_write_congestion(mapping, 0); | |
387 | } | |
388 | err = nfs_flush_inode(inode, 0, 0, wb_priority(wbc)); | |
389 | if (err < 0) | |
390 | goto out; | |
91d5b470 | 391 | nfs_add_stats(inode, NFSIOS_WRITEPAGES, err); |
1da177e4 LT |
392 | wbc->nr_to_write -= err; |
393 | if (!wbc->nonblocking && wbc->sync_mode == WB_SYNC_ALL) { | |
394 | err = nfs_wait_on_requests(inode, 0, 0); | |
395 | if (err < 0) | |
396 | goto out; | |
397 | } | |
3da28eb1 | 398 | err = nfs_commit_inode(inode, wb_priority(wbc)); |
1da177e4 LT |
399 | if (err > 0) { |
400 | wbc->nr_to_write -= err; | |
401 | err = 0; | |
402 | } | |
403 | out: | |
404 | clear_bit(BDI_write_congested, &bdi->state); | |
405 | wake_up_all(&nfs_write_congestion); | |
406 | return err; | |
407 | } | |
408 | ||
409 | /* | |
410 | * Insert a write request into an inode | |
411 | */ | |
412 | static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req) | |
413 | { | |
414 | struct nfs_inode *nfsi = NFS_I(inode); | |
415 | int error; | |
416 | ||
417 | error = radix_tree_insert(&nfsi->nfs_page_tree, req->wb_index, req); | |
418 | BUG_ON(error == -EEXIST); | |
419 | if (error) | |
420 | return error; | |
421 | if (!nfsi->npages) { | |
422 | igrab(inode); | |
423 | nfs_begin_data_update(inode); | |
424 | if (nfs_have_delegation(inode, FMODE_WRITE)) | |
425 | nfsi->change_attr++; | |
426 | } | |
deb7d638 | 427 | SetPagePrivate(req->wb_page); |
1da177e4 LT |
428 | nfsi->npages++; |
429 | atomic_inc(&req->wb_count); | |
430 | return 0; | |
431 | } | |
432 | ||
433 | /* | |
434 | * Insert a write request into an inode | |
435 | */ | |
436 | static void nfs_inode_remove_request(struct nfs_page *req) | |
437 | { | |
438 | struct inode *inode = req->wb_context->dentry->d_inode; | |
439 | struct nfs_inode *nfsi = NFS_I(inode); | |
440 | ||
441 | BUG_ON (!NFS_WBACK_BUSY(req)); | |
442 | ||
443 | spin_lock(&nfsi->req_lock); | |
deb7d638 | 444 | ClearPagePrivate(req->wb_page); |
1da177e4 LT |
445 | radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index); |
446 | nfsi->npages--; | |
447 | if (!nfsi->npages) { | |
448 | spin_unlock(&nfsi->req_lock); | |
951a143b | 449 | nfs_end_data_update(inode); |
1da177e4 LT |
450 | iput(inode); |
451 | } else | |
452 | spin_unlock(&nfsi->req_lock); | |
453 | nfs_clear_request(req); | |
454 | nfs_release_request(req); | |
455 | } | |
456 | ||
457 | /* | |
458 | * Find a request | |
459 | */ | |
460 | static inline struct nfs_page * | |
461 | _nfs_find_request(struct inode *inode, unsigned long index) | |
462 | { | |
463 | struct nfs_inode *nfsi = NFS_I(inode); | |
464 | struct nfs_page *req; | |
465 | ||
466 | req = (struct nfs_page*)radix_tree_lookup(&nfsi->nfs_page_tree, index); | |
467 | if (req) | |
468 | atomic_inc(&req->wb_count); | |
469 | return req; | |
470 | } | |
471 | ||
472 | static struct nfs_page * | |
473 | nfs_find_request(struct inode *inode, unsigned long index) | |
474 | { | |
475 | struct nfs_page *req; | |
476 | struct nfs_inode *nfsi = NFS_I(inode); | |
477 | ||
478 | spin_lock(&nfsi->req_lock); | |
479 | req = _nfs_find_request(inode, index); | |
480 | spin_unlock(&nfsi->req_lock); | |
481 | return req; | |
482 | } | |
483 | ||
484 | /* | |
485 | * Add a request to the inode's dirty list. | |
486 | */ | |
487 | static void | |
488 | nfs_mark_request_dirty(struct nfs_page *req) | |
489 | { | |
490 | struct inode *inode = req->wb_context->dentry->d_inode; | |
491 | struct nfs_inode *nfsi = NFS_I(inode); | |
492 | ||
493 | spin_lock(&nfsi->req_lock); | |
3da28eb1 TM |
494 | radix_tree_tag_set(&nfsi->nfs_page_tree, |
495 | req->wb_index, NFS_PAGE_TAG_DIRTY); | |
1da177e4 LT |
496 | nfs_list_add_request(req, &nfsi->dirty); |
497 | nfsi->ndirty++; | |
498 | spin_unlock(&nfsi->req_lock); | |
b1e7a8fd | 499 | inc_zone_page_state(req->wb_page, NR_FILE_DIRTY); |
1da177e4 LT |
500 | mark_inode_dirty(inode); |
501 | } | |
502 | ||
503 | /* | |
504 | * Check if a request is dirty | |
505 | */ | |
506 | static inline int | |
507 | nfs_dirty_request(struct nfs_page *req) | |
508 | { | |
509 | struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode); | |
510 | return !list_empty(&req->wb_list) && req->wb_list_head == &nfsi->dirty; | |
511 | } | |
512 | ||
513 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
514 | /* | |
515 | * Add a request to the inode's commit list. | |
516 | */ | |
517 | static void | |
518 | nfs_mark_request_commit(struct nfs_page *req) | |
519 | { | |
520 | struct inode *inode = req->wb_context->dentry->d_inode; | |
521 | struct nfs_inode *nfsi = NFS_I(inode); | |
522 | ||
523 | spin_lock(&nfsi->req_lock); | |
524 | nfs_list_add_request(req, &nfsi->commit); | |
525 | nfsi->ncommit++; | |
526 | spin_unlock(&nfsi->req_lock); | |
fd39fc85 | 527 | inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS); |
1da177e4 LT |
528 | mark_inode_dirty(inode); |
529 | } | |
530 | #endif | |
531 | ||
532 | /* | |
533 | * Wait for a request to complete. | |
534 | * | |
535 | * Interruptible by signals only if mounted with intr flag. | |
536 | */ | |
c42de9dd | 537 | static int nfs_wait_on_requests_locked(struct inode *inode, unsigned long idx_start, unsigned int npages) |
1da177e4 LT |
538 | { |
539 | struct nfs_inode *nfsi = NFS_I(inode); | |
540 | struct nfs_page *req; | |
541 | unsigned long idx_end, next; | |
542 | unsigned int res = 0; | |
543 | int error; | |
544 | ||
545 | if (npages == 0) | |
546 | idx_end = ~0; | |
547 | else | |
548 | idx_end = idx_start + npages - 1; | |
549 | ||
1da177e4 | 550 | next = idx_start; |
c6a556b8 | 551 | while (radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree, (void **)&req, next, 1, NFS_PAGE_TAG_WRITEBACK)) { |
1da177e4 LT |
552 | if (req->wb_index > idx_end) |
553 | break; | |
554 | ||
555 | next = req->wb_index + 1; | |
c6a556b8 | 556 | BUG_ON(!NFS_WBACK_BUSY(req)); |
1da177e4 LT |
557 | |
558 | atomic_inc(&req->wb_count); | |
559 | spin_unlock(&nfsi->req_lock); | |
560 | error = nfs_wait_on_request(req); | |
561 | nfs_release_request(req); | |
c42de9dd | 562 | spin_lock(&nfsi->req_lock); |
1da177e4 LT |
563 | if (error < 0) |
564 | return error; | |
1da177e4 LT |
565 | res++; |
566 | } | |
1da177e4 LT |
567 | return res; |
568 | } | |
569 | ||
c42de9dd TM |
570 | static int nfs_wait_on_requests(struct inode *inode, unsigned long idx_start, unsigned int npages) |
571 | { | |
572 | struct nfs_inode *nfsi = NFS_I(inode); | |
573 | int ret; | |
574 | ||
575 | spin_lock(&nfsi->req_lock); | |
576 | ret = nfs_wait_on_requests_locked(inode, idx_start, npages); | |
577 | spin_unlock(&nfsi->req_lock); | |
578 | return ret; | |
579 | } | |
580 | ||
d2ccddf0 TM |
581 | static void nfs_cancel_requests(struct list_head *head) |
582 | { | |
583 | struct nfs_page *req; | |
584 | while(!list_empty(head)) { | |
585 | req = nfs_list_entry(head->next); | |
586 | nfs_list_remove_request(req); | |
587 | nfs_inode_remove_request(req); | |
588 | nfs_clear_page_writeback(req); | |
589 | } | |
590 | } | |
591 | ||
1da177e4 LT |
592 | /* |
593 | * nfs_scan_dirty - Scan an inode for dirty requests | |
594 | * @inode: NFS inode to scan | |
595 | * @dst: destination list | |
596 | * @idx_start: lower bound of page->index to scan. | |
597 | * @npages: idx_start + npages sets the upper bound to scan. | |
598 | * | |
599 | * Moves requests from the inode's dirty page list. | |
600 | * The requests are *not* checked to ensure that they form a contiguous set. | |
601 | */ | |
602 | static int | |
603 | nfs_scan_dirty(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
604 | { | |
605 | struct nfs_inode *nfsi = NFS_I(inode); | |
3da28eb1 TM |
606 | int res = 0; |
607 | ||
608 | if (nfsi->ndirty != 0) { | |
609 | res = nfs_scan_lock_dirty(nfsi, dst, idx_start, npages); | |
610 | nfsi->ndirty -= res; | |
3da28eb1 TM |
611 | if ((nfsi->ndirty == 0) != list_empty(&nfsi->dirty)) |
612 | printk(KERN_ERR "NFS: desynchronized value of nfs_i.ndirty.\n"); | |
613 | } | |
1da177e4 LT |
614 | return res; |
615 | } | |
616 | ||
617 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
618 | /* | |
619 | * nfs_scan_commit - Scan an inode for commit requests | |
620 | * @inode: NFS inode to scan | |
621 | * @dst: destination list | |
622 | * @idx_start: lower bound of page->index to scan. | |
623 | * @npages: idx_start + npages sets the upper bound to scan. | |
624 | * | |
625 | * Moves requests from the inode's 'commit' request list. | |
626 | * The requests are *not* checked to ensure that they form a contiguous set. | |
627 | */ | |
628 | static int | |
629 | nfs_scan_commit(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
630 | { | |
631 | struct nfs_inode *nfsi = NFS_I(inode); | |
3da28eb1 TM |
632 | int res = 0; |
633 | ||
634 | if (nfsi->ncommit != 0) { | |
d2ccddf0 | 635 | res = nfs_scan_list(nfsi, &nfsi->commit, dst, idx_start, npages); |
3da28eb1 TM |
636 | nfsi->ncommit -= res; |
637 | if ((nfsi->ncommit == 0) != list_empty(&nfsi->commit)) | |
638 | printk(KERN_ERR "NFS: desynchronized value of nfs_i.ncommit.\n"); | |
639 | } | |
1da177e4 LT |
640 | return res; |
641 | } | |
c42de9dd TM |
642 | #else |
643 | static inline int nfs_scan_commit(struct inode *inode, struct list_head *dst, unsigned long idx_start, unsigned int npages) | |
644 | { | |
645 | return 0; | |
646 | } | |
1da177e4 LT |
647 | #endif |
648 | ||
649 | static int nfs_wait_on_write_congestion(struct address_space *mapping, int intr) | |
650 | { | |
651 | struct backing_dev_info *bdi = mapping->backing_dev_info; | |
652 | DEFINE_WAIT(wait); | |
653 | int ret = 0; | |
654 | ||
655 | might_sleep(); | |
656 | ||
657 | if (!bdi_write_congested(bdi)) | |
658 | return 0; | |
91d5b470 CL |
659 | |
660 | nfs_inc_stats(mapping->host, NFSIOS_CONGESTIONWAIT); | |
661 | ||
1da177e4 LT |
662 | if (intr) { |
663 | struct rpc_clnt *clnt = NFS_CLIENT(mapping->host); | |
664 | sigset_t oldset; | |
665 | ||
666 | rpc_clnt_sigmask(clnt, &oldset); | |
667 | prepare_to_wait(&nfs_write_congestion, &wait, TASK_INTERRUPTIBLE); | |
668 | if (bdi_write_congested(bdi)) { | |
669 | if (signalled()) | |
670 | ret = -ERESTARTSYS; | |
671 | else | |
672 | schedule(); | |
673 | } | |
674 | rpc_clnt_sigunmask(clnt, &oldset); | |
675 | } else { | |
676 | prepare_to_wait(&nfs_write_congestion, &wait, TASK_UNINTERRUPTIBLE); | |
677 | if (bdi_write_congested(bdi)) | |
678 | schedule(); | |
679 | } | |
680 | finish_wait(&nfs_write_congestion, &wait); | |
681 | return ret; | |
682 | } | |
683 | ||
684 | ||
685 | /* | |
686 | * Try to update any existing write request, or create one if there is none. | |
687 | * In order to match, the request's credentials must match those of | |
688 | * the calling process. | |
689 | * | |
690 | * Note: Should always be called with the Page Lock held! | |
691 | */ | |
692 | static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx, | |
693 | struct inode *inode, struct page *page, | |
694 | unsigned int offset, unsigned int bytes) | |
695 | { | |
696 | struct nfs_server *server = NFS_SERVER(inode); | |
697 | struct nfs_inode *nfsi = NFS_I(inode); | |
698 | struct nfs_page *req, *new = NULL; | |
699 | unsigned long rqend, end; | |
700 | ||
701 | end = offset + bytes; | |
702 | ||
703 | if (nfs_wait_on_write_congestion(page->mapping, server->flags & NFS_MOUNT_INTR)) | |
704 | return ERR_PTR(-ERESTARTSYS); | |
705 | for (;;) { | |
706 | /* Loop over all inode entries and see if we find | |
707 | * A request for the page we wish to update | |
708 | */ | |
709 | spin_lock(&nfsi->req_lock); | |
710 | req = _nfs_find_request(inode, page->index); | |
711 | if (req) { | |
712 | if (!nfs_lock_request_dontget(req)) { | |
713 | int error; | |
714 | spin_unlock(&nfsi->req_lock); | |
715 | error = nfs_wait_on_request(req); | |
716 | nfs_release_request(req); | |
1dd594b2 NB |
717 | if (error < 0) { |
718 | if (new) | |
719 | nfs_release_request(new); | |
1da177e4 | 720 | return ERR_PTR(error); |
1dd594b2 | 721 | } |
1da177e4 LT |
722 | continue; |
723 | } | |
724 | spin_unlock(&nfsi->req_lock); | |
725 | if (new) | |
726 | nfs_release_request(new); | |
727 | break; | |
728 | } | |
729 | ||
730 | if (new) { | |
731 | int error; | |
732 | nfs_lock_request_dontget(new); | |
733 | error = nfs_inode_add_request(inode, new); | |
734 | if (error) { | |
735 | spin_unlock(&nfsi->req_lock); | |
736 | nfs_unlock_request(new); | |
737 | return ERR_PTR(error); | |
738 | } | |
739 | spin_unlock(&nfsi->req_lock); | |
740 | nfs_mark_request_dirty(new); | |
741 | return new; | |
742 | } | |
743 | spin_unlock(&nfsi->req_lock); | |
744 | ||
745 | new = nfs_create_request(ctx, inode, page, offset, bytes); | |
746 | if (IS_ERR(new)) | |
747 | return new; | |
748 | } | |
749 | ||
750 | /* We have a request for our page. | |
751 | * If the creds don't match, or the | |
752 | * page addresses don't match, | |
753 | * tell the caller to wait on the conflicting | |
754 | * request. | |
755 | */ | |
756 | rqend = req->wb_offset + req->wb_bytes; | |
757 | if (req->wb_context != ctx | |
758 | || req->wb_page != page | |
759 | || !nfs_dirty_request(req) | |
760 | || offset > rqend || end < req->wb_offset) { | |
761 | nfs_unlock_request(req); | |
762 | return ERR_PTR(-EBUSY); | |
763 | } | |
764 | ||
765 | /* Okay, the request matches. Update the region */ | |
766 | if (offset < req->wb_offset) { | |
767 | req->wb_offset = offset; | |
768 | req->wb_pgbase = offset; | |
769 | req->wb_bytes = rqend - req->wb_offset; | |
770 | } | |
771 | ||
772 | if (end > rqend) | |
773 | req->wb_bytes = end - req->wb_offset; | |
774 | ||
775 | return req; | |
776 | } | |
777 | ||
778 | int nfs_flush_incompatible(struct file *file, struct page *page) | |
779 | { | |
780 | struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data; | |
781 | struct inode *inode = page->mapping->host; | |
782 | struct nfs_page *req; | |
783 | int status = 0; | |
784 | /* | |
785 | * Look for a request corresponding to this page. If there | |
786 | * is one, and it belongs to another file, we flush it out | |
787 | * before we try to copy anything into the page. Do this | |
788 | * due to the lack of an ACCESS-type call in NFSv2. | |
789 | * Also do the same if we find a request from an existing | |
790 | * dropped page. | |
791 | */ | |
792 | req = nfs_find_request(inode, page->index); | |
793 | if (req) { | |
794 | if (req->wb_page != page || ctx != req->wb_context) | |
795 | status = nfs_wb_page(inode, page); | |
796 | nfs_release_request(req); | |
797 | } | |
798 | return (status < 0) ? status : 0; | |
799 | } | |
800 | ||
801 | /* | |
802 | * Update and possibly write a cached page of an NFS file. | |
803 | * | |
804 | * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad | |
805 | * things with a page scheduled for an RPC call (e.g. invalidate it). | |
806 | */ | |
807 | int nfs_updatepage(struct file *file, struct page *page, | |
808 | unsigned int offset, unsigned int count) | |
809 | { | |
810 | struct nfs_open_context *ctx = (struct nfs_open_context *)file->private_data; | |
1da177e4 LT |
811 | struct inode *inode = page->mapping->host; |
812 | struct nfs_page *req; | |
813 | int status = 0; | |
814 | ||
91d5b470 CL |
815 | nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE); |
816 | ||
1da177e4 | 817 | dprintk("NFS: nfs_updatepage(%s/%s %d@%Ld)\n", |
0bbacc40 CL |
818 | file->f_dentry->d_parent->d_name.name, |
819 | file->f_dentry->d_name.name, count, | |
820 | (long long)(page_offset(page) +offset)); | |
1da177e4 LT |
821 | |
822 | if (IS_SYNC(inode)) { | |
823 | status = nfs_writepage_sync(ctx, inode, page, offset, count, 0); | |
824 | if (status > 0) { | |
825 | if (offset == 0 && status == PAGE_CACHE_SIZE) | |
826 | SetPageUptodate(page); | |
827 | return 0; | |
828 | } | |
829 | return status; | |
830 | } | |
831 | ||
832 | /* If we're not using byte range locks, and we know the page | |
833 | * is entirely in cache, it may be more efficient to avoid | |
834 | * fragmenting write requests. | |
835 | */ | |
ab0a3dbe | 836 | if (PageUptodate(page) && inode->i_flock == NULL && !(file->f_mode & O_SYNC)) { |
1da177e4 LT |
837 | loff_t end_offs = i_size_read(inode) - 1; |
838 | unsigned long end_index = end_offs >> PAGE_CACHE_SHIFT; | |
839 | ||
840 | count += offset; | |
841 | offset = 0; | |
842 | if (unlikely(end_offs < 0)) { | |
843 | /* Do nothing */ | |
844 | } else if (page->index == end_index) { | |
845 | unsigned int pglen; | |
846 | pglen = (unsigned int)(end_offs & (PAGE_CACHE_SIZE-1)) + 1; | |
847 | if (count < pglen) | |
848 | count = pglen; | |
849 | } else if (page->index < end_index) | |
850 | count = PAGE_CACHE_SIZE; | |
851 | } | |
852 | ||
853 | /* | |
854 | * Try to find an NFS request corresponding to this page | |
855 | * and update it. | |
856 | * If the existing request cannot be updated, we must flush | |
857 | * it out now. | |
858 | */ | |
859 | do { | |
860 | req = nfs_update_request(ctx, inode, page, offset, count); | |
861 | status = (IS_ERR(req)) ? PTR_ERR(req) : 0; | |
862 | if (status != -EBUSY) | |
863 | break; | |
864 | /* Request could not be updated. Flush it out and try again */ | |
865 | status = nfs_wb_page(inode, page); | |
866 | } while (status >= 0); | |
867 | if (status < 0) | |
868 | goto done; | |
869 | ||
870 | status = 0; | |
871 | ||
872 | /* Update file length */ | |
873 | nfs_grow_file(page, offset, count); | |
874 | /* Set the PG_uptodate flag? */ | |
875 | nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes); | |
876 | nfs_unlock_request(req); | |
877 | done: | |
878 | dprintk("NFS: nfs_updatepage returns %d (isize %Ld)\n", | |
879 | status, (long long)i_size_read(inode)); | |
880 | if (status < 0) | |
881 | ClearPageUptodate(page); | |
882 | return status; | |
883 | } | |
884 | ||
885 | static void nfs_writepage_release(struct nfs_page *req) | |
886 | { | |
887 | end_page_writeback(req->wb_page); | |
888 | ||
889 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
890 | if (!PageError(req->wb_page)) { | |
891 | if (NFS_NEED_RESCHED(req)) { | |
892 | nfs_mark_request_dirty(req); | |
893 | goto out; | |
894 | } else if (NFS_NEED_COMMIT(req)) { | |
895 | nfs_mark_request_commit(req); | |
896 | goto out; | |
897 | } | |
898 | } | |
899 | nfs_inode_remove_request(req); | |
900 | ||
901 | out: | |
902 | nfs_clear_commit(req); | |
903 | nfs_clear_reschedule(req); | |
904 | #else | |
905 | nfs_inode_remove_request(req); | |
906 | #endif | |
c6a556b8 | 907 | nfs_clear_page_writeback(req); |
1da177e4 LT |
908 | } |
909 | ||
910 | static inline int flush_task_priority(int how) | |
911 | { | |
912 | switch (how & (FLUSH_HIGHPRI|FLUSH_LOWPRI)) { | |
913 | case FLUSH_HIGHPRI: | |
914 | return RPC_PRIORITY_HIGH; | |
915 | case FLUSH_LOWPRI: | |
916 | return RPC_PRIORITY_LOW; | |
917 | } | |
918 | return RPC_PRIORITY_NORMAL; | |
919 | } | |
920 | ||
921 | /* | |
922 | * Set up the argument/result storage required for the RPC call. | |
923 | */ | |
924 | static void nfs_write_rpcsetup(struct nfs_page *req, | |
925 | struct nfs_write_data *data, | |
788e7a89 | 926 | const struct rpc_call_ops *call_ops, |
1da177e4 LT |
927 | unsigned int count, unsigned int offset, |
928 | int how) | |
929 | { | |
1da177e4 | 930 | struct inode *inode; |
788e7a89 | 931 | int flags; |
1da177e4 LT |
932 | |
933 | /* Set up the RPC argument and reply structs | |
934 | * NB: take care not to mess about with data->commit et al. */ | |
935 | ||
936 | data->req = req; | |
937 | data->inode = inode = req->wb_context->dentry->d_inode; | |
938 | data->cred = req->wb_context->cred; | |
939 | ||
940 | data->args.fh = NFS_FH(inode); | |
941 | data->args.offset = req_offset(req) + offset; | |
942 | data->args.pgbase = req->wb_pgbase + offset; | |
943 | data->args.pages = data->pagevec; | |
944 | data->args.count = count; | |
945 | data->args.context = req->wb_context; | |
946 | ||
947 | data->res.fattr = &data->fattr; | |
948 | data->res.count = count; | |
949 | data->res.verf = &data->verf; | |
0e574af1 | 950 | nfs_fattr_init(&data->fattr); |
1da177e4 | 951 | |
788e7a89 TM |
952 | /* Set up the initial task struct. */ |
953 | flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC; | |
954 | rpc_init_task(&data->task, NFS_CLIENT(inode), flags, call_ops, data); | |
1da177e4 LT |
955 | NFS_PROTO(inode)->write_setup(data, how); |
956 | ||
957 | data->task.tk_priority = flush_task_priority(how); | |
958 | data->task.tk_cookie = (unsigned long)inode; | |
1da177e4 LT |
959 | |
960 | dprintk("NFS: %4d initiated write call (req %s/%Ld, %u bytes @ offset %Lu)\n", | |
0bbacc40 | 961 | data->task.tk_pid, |
1da177e4 LT |
962 | inode->i_sb->s_id, |
963 | (long long)NFS_FILEID(inode), | |
964 | count, | |
965 | (unsigned long long)data->args.offset); | |
966 | } | |
967 | ||
968 | static void nfs_execute_write(struct nfs_write_data *data) | |
969 | { | |
970 | struct rpc_clnt *clnt = NFS_CLIENT(data->inode); | |
971 | sigset_t oldset; | |
972 | ||
973 | rpc_clnt_sigmask(clnt, &oldset); | |
974 | lock_kernel(); | |
975 | rpc_execute(&data->task); | |
976 | unlock_kernel(); | |
977 | rpc_clnt_sigunmask(clnt, &oldset); | |
978 | } | |
979 | ||
980 | /* | |
981 | * Generate multiple small requests to write out a single | |
982 | * contiguous dirty area on one page. | |
983 | */ | |
7d46a49f | 984 | static int nfs_flush_multi(struct inode *inode, struct list_head *head, int how) |
1da177e4 LT |
985 | { |
986 | struct nfs_page *req = nfs_list_entry(head->next); | |
987 | struct page *page = req->wb_page; | |
988 | struct nfs_write_data *data; | |
989 | unsigned int wsize = NFS_SERVER(inode)->wsize; | |
990 | unsigned int nbytes, offset; | |
991 | int requests = 0; | |
992 | LIST_HEAD(list); | |
993 | ||
994 | nfs_list_remove_request(req); | |
995 | ||
996 | nbytes = req->wb_bytes; | |
997 | for (;;) { | |
40859d7e | 998 | data = nfs_writedata_alloc(1); |
1da177e4 LT |
999 | if (!data) |
1000 | goto out_bad; | |
1001 | list_add(&data->pages, &list); | |
1002 | requests++; | |
1003 | if (nbytes <= wsize) | |
1004 | break; | |
1005 | nbytes -= wsize; | |
1006 | } | |
1007 | atomic_set(&req->wb_complete, requests); | |
1008 | ||
1009 | ClearPageError(page); | |
bb713d6d | 1010 | set_page_writeback(page); |
1da177e4 LT |
1011 | offset = 0; |
1012 | nbytes = req->wb_bytes; | |
1013 | do { | |
1014 | data = list_entry(list.next, struct nfs_write_data, pages); | |
1015 | list_del_init(&data->pages); | |
1016 | ||
1017 | data->pagevec[0] = page; | |
1da177e4 LT |
1018 | |
1019 | if (nbytes > wsize) { | |
788e7a89 TM |
1020 | nfs_write_rpcsetup(req, data, &nfs_write_partial_ops, |
1021 | wsize, offset, how); | |
1da177e4 LT |
1022 | offset += wsize; |
1023 | nbytes -= wsize; | |
1024 | } else { | |
788e7a89 TM |
1025 | nfs_write_rpcsetup(req, data, &nfs_write_partial_ops, |
1026 | nbytes, offset, how); | |
1da177e4 LT |
1027 | nbytes = 0; |
1028 | } | |
1029 | nfs_execute_write(data); | |
1030 | } while (nbytes != 0); | |
1031 | ||
1032 | return 0; | |
1033 | ||
1034 | out_bad: | |
1035 | while (!list_empty(&list)) { | |
1036 | data = list_entry(list.next, struct nfs_write_data, pages); | |
1037 | list_del(&data->pages); | |
1038 | nfs_writedata_free(data); | |
1039 | } | |
1040 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1041 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1042 | return -ENOMEM; |
1043 | } | |
1044 | ||
1045 | /* | |
1046 | * Create an RPC task for the given write request and kick it. | |
1047 | * The page must have been locked by the caller. | |
1048 | * | |
1049 | * It may happen that the page we're passed is not marked dirty. | |
1050 | * This is the case if nfs_updatepage detects a conflicting request | |
1051 | * that has been written but not committed. | |
1052 | */ | |
7d46a49f | 1053 | static int nfs_flush_one(struct inode *inode, struct list_head *head, int how) |
1da177e4 LT |
1054 | { |
1055 | struct nfs_page *req; | |
1056 | struct page **pages; | |
1057 | struct nfs_write_data *data; | |
1058 | unsigned int count; | |
1059 | ||
40859d7e | 1060 | data = nfs_writedata_alloc(NFS_SERVER(inode)->wpages); |
1da177e4 LT |
1061 | if (!data) |
1062 | goto out_bad; | |
1063 | ||
1064 | pages = data->pagevec; | |
1065 | count = 0; | |
1066 | while (!list_empty(head)) { | |
1067 | req = nfs_list_entry(head->next); | |
1068 | nfs_list_remove_request(req); | |
1069 | nfs_list_add_request(req, &data->pages); | |
1070 | ClearPageError(req->wb_page); | |
bb713d6d | 1071 | set_page_writeback(req->wb_page); |
1da177e4 LT |
1072 | *pages++ = req->wb_page; |
1073 | count += req->wb_bytes; | |
1074 | } | |
1075 | req = nfs_list_entry(data->pages.next); | |
1076 | ||
1da177e4 | 1077 | /* Set up the argument struct */ |
788e7a89 | 1078 | nfs_write_rpcsetup(req, data, &nfs_write_full_ops, count, 0, how); |
1da177e4 LT |
1079 | |
1080 | nfs_execute_write(data); | |
1081 | return 0; | |
1082 | out_bad: | |
1083 | while (!list_empty(head)) { | |
1084 | struct nfs_page *req = nfs_list_entry(head->next); | |
1085 | nfs_list_remove_request(req); | |
1086 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1087 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1088 | } |
1089 | return -ENOMEM; | |
1090 | } | |
1091 | ||
7d46a49f | 1092 | static int nfs_flush_list(struct inode *inode, struct list_head *head, int npages, int how) |
1da177e4 LT |
1093 | { |
1094 | LIST_HEAD(one_request); | |
7d46a49f TM |
1095 | int (*flush_one)(struct inode *, struct list_head *, int); |
1096 | struct nfs_page *req; | |
1097 | int wpages = NFS_SERVER(inode)->wpages; | |
1098 | int wsize = NFS_SERVER(inode)->wsize; | |
1099 | int error; | |
1da177e4 | 1100 | |
7d46a49f TM |
1101 | flush_one = nfs_flush_one; |
1102 | if (wsize < PAGE_CACHE_SIZE) | |
1103 | flush_one = nfs_flush_multi; | |
1104 | /* For single writes, FLUSH_STABLE is more efficient */ | |
1105 | if (npages <= wpages && npages == NFS_I(inode)->npages | |
1106 | && nfs_list_entry(head->next)->wb_bytes <= wsize) | |
1107 | how |= FLUSH_STABLE; | |
1108 | ||
1109 | do { | |
1110 | nfs_coalesce_requests(head, &one_request, wpages); | |
1da177e4 | 1111 | req = nfs_list_entry(one_request.next); |
7d46a49f | 1112 | error = flush_one(inode, &one_request, how); |
1da177e4 | 1113 | if (error < 0) |
7d46a49f TM |
1114 | goto out_err; |
1115 | } while (!list_empty(head)); | |
1116 | return 0; | |
1117 | out_err: | |
1da177e4 LT |
1118 | while (!list_empty(head)) { |
1119 | req = nfs_list_entry(head->next); | |
1120 | nfs_list_remove_request(req); | |
1121 | nfs_mark_request_dirty(req); | |
c6a556b8 | 1122 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1123 | } |
1124 | return error; | |
1125 | } | |
1126 | ||
1127 | /* | |
1128 | * Handle a write reply that flushed part of a page. | |
1129 | */ | |
788e7a89 | 1130 | static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata) |
1da177e4 | 1131 | { |
788e7a89 | 1132 | struct nfs_write_data *data = calldata; |
1da177e4 LT |
1133 | struct nfs_page *req = data->req; |
1134 | struct page *page = req->wb_page; | |
1135 | ||
1136 | dprintk("NFS: write (%s/%Ld %d@%Ld)", | |
1137 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1138 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1139 | req->wb_bytes, | |
1140 | (long long)req_offset(req)); | |
1141 | ||
788e7a89 TM |
1142 | if (nfs_writeback_done(task, data) != 0) |
1143 | return; | |
1144 | ||
1145 | if (task->tk_status < 0) { | |
1da177e4 LT |
1146 | ClearPageUptodate(page); |
1147 | SetPageError(page); | |
788e7a89 TM |
1148 | req->wb_context->error = task->tk_status; |
1149 | dprintk(", error = %d\n", task->tk_status); | |
1da177e4 LT |
1150 | } else { |
1151 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1152 | if (data->verf.committed < NFS_FILE_SYNC) { | |
1153 | if (!NFS_NEED_COMMIT(req)) { | |
1154 | nfs_defer_commit(req); | |
1155 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1156 | dprintk(" defer commit\n"); | |
1157 | } else if (memcmp(&req->wb_verf, &data->verf, sizeof(req->wb_verf))) { | |
1158 | nfs_defer_reschedule(req); | |
1159 | dprintk(" server reboot detected\n"); | |
1160 | } | |
1161 | } else | |
1162 | #endif | |
1163 | dprintk(" OK\n"); | |
1164 | } | |
1165 | ||
1166 | if (atomic_dec_and_test(&req->wb_complete)) | |
1167 | nfs_writepage_release(req); | |
1168 | } | |
1169 | ||
788e7a89 TM |
1170 | static const struct rpc_call_ops nfs_write_partial_ops = { |
1171 | .rpc_call_done = nfs_writeback_done_partial, | |
1172 | .rpc_release = nfs_writedata_release, | |
1173 | }; | |
1174 | ||
1da177e4 LT |
1175 | /* |
1176 | * Handle a write reply that flushes a whole page. | |
1177 | * | |
1178 | * FIXME: There is an inherent race with invalidate_inode_pages and | |
1179 | * writebacks since the page->count is kept > 1 for as long | |
1180 | * as the page has a write request pending. | |
1181 | */ | |
788e7a89 | 1182 | static void nfs_writeback_done_full(struct rpc_task *task, void *calldata) |
1da177e4 | 1183 | { |
788e7a89 | 1184 | struct nfs_write_data *data = calldata; |
1da177e4 LT |
1185 | struct nfs_page *req; |
1186 | struct page *page; | |
1187 | ||
788e7a89 TM |
1188 | if (nfs_writeback_done(task, data) != 0) |
1189 | return; | |
1190 | ||
1da177e4 LT |
1191 | /* Update attributes as result of writeback. */ |
1192 | while (!list_empty(&data->pages)) { | |
1193 | req = nfs_list_entry(data->pages.next); | |
1194 | nfs_list_remove_request(req); | |
1195 | page = req->wb_page; | |
1196 | ||
1197 | dprintk("NFS: write (%s/%Ld %d@%Ld)", | |
1198 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1199 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1200 | req->wb_bytes, | |
1201 | (long long)req_offset(req)); | |
1202 | ||
788e7a89 | 1203 | if (task->tk_status < 0) { |
1da177e4 LT |
1204 | ClearPageUptodate(page); |
1205 | SetPageError(page); | |
788e7a89 | 1206 | req->wb_context->error = task->tk_status; |
1da177e4 LT |
1207 | end_page_writeback(page); |
1208 | nfs_inode_remove_request(req); | |
788e7a89 | 1209 | dprintk(", error = %d\n", task->tk_status); |
1da177e4 LT |
1210 | goto next; |
1211 | } | |
1212 | end_page_writeback(page); | |
1213 | ||
1214 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
1215 | if (data->args.stable != NFS_UNSTABLE || data->verf.committed == NFS_FILE_SYNC) { | |
1216 | nfs_inode_remove_request(req); | |
1217 | dprintk(" OK\n"); | |
1218 | goto next; | |
1219 | } | |
1220 | memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf)); | |
1221 | nfs_mark_request_commit(req); | |
1222 | dprintk(" marked for commit\n"); | |
1223 | #else | |
1224 | nfs_inode_remove_request(req); | |
1225 | #endif | |
1226 | next: | |
c6a556b8 | 1227 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1228 | } |
1229 | } | |
1230 | ||
788e7a89 TM |
1231 | static const struct rpc_call_ops nfs_write_full_ops = { |
1232 | .rpc_call_done = nfs_writeback_done_full, | |
1233 | .rpc_release = nfs_writedata_release, | |
1234 | }; | |
1235 | ||
1236 | ||
1da177e4 LT |
1237 | /* |
1238 | * This function is called when the WRITE call is complete. | |
1239 | */ | |
462d5b32 | 1240 | int nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data) |
1da177e4 | 1241 | { |
1da177e4 LT |
1242 | struct nfs_writeargs *argp = &data->args; |
1243 | struct nfs_writeres *resp = &data->res; | |
788e7a89 | 1244 | int status; |
1da177e4 LT |
1245 | |
1246 | dprintk("NFS: %4d nfs_writeback_done (status %d)\n", | |
1247 | task->tk_pid, task->tk_status); | |
1248 | ||
788e7a89 TM |
1249 | /* Call the NFS version-specific code */ |
1250 | status = NFS_PROTO(data->inode)->write_done(task, data); | |
1251 | if (status != 0) | |
1252 | return status; | |
91d5b470 CL |
1253 | nfs_add_stats(data->inode, NFSIOS_SERVERWRITTENBYTES, resp->count); |
1254 | ||
1da177e4 LT |
1255 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) |
1256 | if (resp->verf->committed < argp->stable && task->tk_status >= 0) { | |
1257 | /* We tried a write call, but the server did not | |
1258 | * commit data to stable storage even though we | |
1259 | * requested it. | |
1260 | * Note: There is a known bug in Tru64 < 5.0 in which | |
1261 | * the server reports NFS_DATA_SYNC, but performs | |
1262 | * NFS_FILE_SYNC. We therefore implement this checking | |
1263 | * as a dprintk() in order to avoid filling syslog. | |
1264 | */ | |
1265 | static unsigned long complain; | |
1266 | ||
1267 | if (time_before(complain, jiffies)) { | |
1268 | dprintk("NFS: faulty NFS server %s:" | |
1269 | " (committed = %d) != (stable = %d)\n", | |
1270 | NFS_SERVER(data->inode)->hostname, | |
1271 | resp->verf->committed, argp->stable); | |
1272 | complain = jiffies + 300 * HZ; | |
1273 | } | |
1274 | } | |
1275 | #endif | |
1276 | /* Is this a short write? */ | |
1277 | if (task->tk_status >= 0 && resp->count < argp->count) { | |
1278 | static unsigned long complain; | |
1279 | ||
91d5b470 CL |
1280 | nfs_inc_stats(data->inode, NFSIOS_SHORTWRITE); |
1281 | ||
1da177e4 LT |
1282 | /* Has the server at least made some progress? */ |
1283 | if (resp->count != 0) { | |
1284 | /* Was this an NFSv2 write or an NFSv3 stable write? */ | |
1285 | if (resp->verf->committed != NFS_UNSTABLE) { | |
1286 | /* Resend from where the server left off */ | |
1287 | argp->offset += resp->count; | |
1288 | argp->pgbase += resp->count; | |
1289 | argp->count -= resp->count; | |
1290 | } else { | |
1291 | /* Resend as a stable write in order to avoid | |
1292 | * headaches in the case of a server crash. | |
1293 | */ | |
1294 | argp->stable = NFS_FILE_SYNC; | |
1295 | } | |
1296 | rpc_restart_call(task); | |
788e7a89 | 1297 | return -EAGAIN; |
1da177e4 LT |
1298 | } |
1299 | if (time_before(complain, jiffies)) { | |
1300 | printk(KERN_WARNING | |
1301 | "NFS: Server wrote zero bytes, expected %u.\n", | |
1302 | argp->count); | |
1303 | complain = jiffies + 300 * HZ; | |
1304 | } | |
1305 | /* Can't do anything about it except throw an error. */ | |
1306 | task->tk_status = -EIO; | |
1307 | } | |
788e7a89 | 1308 | return 0; |
1da177e4 LT |
1309 | } |
1310 | ||
1311 | ||
1312 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
963d8fe5 | 1313 | void nfs_commit_release(void *wdata) |
1da177e4 | 1314 | { |
1da177e4 LT |
1315 | nfs_commit_free(wdata); |
1316 | } | |
1317 | ||
1318 | /* | |
1319 | * Set up the argument/result storage required for the RPC call. | |
1320 | */ | |
1321 | static void nfs_commit_rpcsetup(struct list_head *head, | |
788e7a89 TM |
1322 | struct nfs_write_data *data, |
1323 | int how) | |
1da177e4 | 1324 | { |
3da28eb1 | 1325 | struct nfs_page *first; |
1da177e4 | 1326 | struct inode *inode; |
788e7a89 | 1327 | int flags; |
1da177e4 LT |
1328 | |
1329 | /* Set up the RPC argument and reply structs | |
1330 | * NB: take care not to mess about with data->commit et al. */ | |
1331 | ||
1332 | list_splice_init(head, &data->pages); | |
1333 | first = nfs_list_entry(data->pages.next); | |
1da177e4 LT |
1334 | inode = first->wb_context->dentry->d_inode; |
1335 | ||
1da177e4 LT |
1336 | data->inode = inode; |
1337 | data->cred = first->wb_context->cred; | |
1338 | ||
1339 | data->args.fh = NFS_FH(data->inode); | |
3da28eb1 TM |
1340 | /* Note: we always request a commit of the entire inode */ |
1341 | data->args.offset = 0; | |
1342 | data->args.count = 0; | |
1343 | data->res.count = 0; | |
1da177e4 LT |
1344 | data->res.fattr = &data->fattr; |
1345 | data->res.verf = &data->verf; | |
0e574af1 | 1346 | nfs_fattr_init(&data->fattr); |
788e7a89 TM |
1347 | |
1348 | /* Set up the initial task struct. */ | |
1349 | flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC; | |
1350 | rpc_init_task(&data->task, NFS_CLIENT(inode), flags, &nfs_commit_ops, data); | |
1da177e4 LT |
1351 | NFS_PROTO(inode)->commit_setup(data, how); |
1352 | ||
1353 | data->task.tk_priority = flush_task_priority(how); | |
1354 | data->task.tk_cookie = (unsigned long)inode; | |
1da177e4 | 1355 | |
0bbacc40 | 1356 | dprintk("NFS: %4d initiated commit call\n", data->task.tk_pid); |
1da177e4 LT |
1357 | } |
1358 | ||
1359 | /* | |
1360 | * Commit dirty pages | |
1361 | */ | |
1362 | static int | |
40859d7e | 1363 | nfs_commit_list(struct inode *inode, struct list_head *head, int how) |
1da177e4 LT |
1364 | { |
1365 | struct nfs_write_data *data; | |
1366 | struct nfs_page *req; | |
1367 | ||
40859d7e | 1368 | data = nfs_commit_alloc(NFS_SERVER(inode)->wpages); |
1da177e4 LT |
1369 | |
1370 | if (!data) | |
1371 | goto out_bad; | |
1372 | ||
1373 | /* Set up the argument struct */ | |
1374 | nfs_commit_rpcsetup(head, data, how); | |
1375 | ||
1376 | nfs_execute_write(data); | |
1377 | return 0; | |
1378 | out_bad: | |
1379 | while (!list_empty(head)) { | |
1380 | req = nfs_list_entry(head->next); | |
1381 | nfs_list_remove_request(req); | |
1382 | nfs_mark_request_commit(req); | |
c6a556b8 | 1383 | nfs_clear_page_writeback(req); |
1da177e4 LT |
1384 | } |
1385 | return -ENOMEM; | |
1386 | } | |
1387 | ||
1388 | /* | |
1389 | * COMMIT call returned | |
1390 | */ | |
788e7a89 | 1391 | static void nfs_commit_done(struct rpc_task *task, void *calldata) |
1da177e4 | 1392 | { |
963d8fe5 | 1393 | struct nfs_write_data *data = calldata; |
1da177e4 | 1394 | struct nfs_page *req; |
1da177e4 LT |
1395 | |
1396 | dprintk("NFS: %4d nfs_commit_done (status %d)\n", | |
1397 | task->tk_pid, task->tk_status); | |
1398 | ||
788e7a89 TM |
1399 | /* Call the NFS version-specific code */ |
1400 | if (NFS_PROTO(data->inode)->commit_done(task, data) != 0) | |
1401 | return; | |
1402 | ||
1da177e4 LT |
1403 | while (!list_empty(&data->pages)) { |
1404 | req = nfs_list_entry(data->pages.next); | |
1405 | nfs_list_remove_request(req); | |
fd39fc85 | 1406 | dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS); |
1da177e4 LT |
1407 | |
1408 | dprintk("NFS: commit (%s/%Ld %d@%Ld)", | |
1409 | req->wb_context->dentry->d_inode->i_sb->s_id, | |
1410 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1411 | req->wb_bytes, | |
1412 | (long long)req_offset(req)); | |
1413 | if (task->tk_status < 0) { | |
1414 | req->wb_context->error = task->tk_status; | |
1415 | nfs_inode_remove_request(req); | |
1416 | dprintk(", error = %d\n", task->tk_status); | |
1417 | goto next; | |
1418 | } | |
1419 | ||
1420 | /* Okay, COMMIT succeeded, apparently. Check the verifier | |
1421 | * returned by the server against all stored verfs. */ | |
1422 | if (!memcmp(req->wb_verf.verifier, data->verf.verifier, sizeof(data->verf.verifier))) { | |
1423 | /* We have a match */ | |
1424 | nfs_inode_remove_request(req); | |
1425 | dprintk(" OK\n"); | |
1426 | goto next; | |
1427 | } | |
1428 | /* We have a mismatch. Write the page again */ | |
1429 | dprintk(" mismatch\n"); | |
1430 | nfs_mark_request_dirty(req); | |
1431 | next: | |
c6a556b8 | 1432 | nfs_clear_page_writeback(req); |
1da177e4 | 1433 | } |
1da177e4 | 1434 | } |
788e7a89 TM |
1435 | |
1436 | static const struct rpc_call_ops nfs_commit_ops = { | |
1437 | .rpc_call_done = nfs_commit_done, | |
1438 | .rpc_release = nfs_commit_release, | |
1439 | }; | |
c42de9dd TM |
1440 | #else |
1441 | static inline int nfs_commit_list(struct inode *inode, struct list_head *head, int how) | |
1442 | { | |
1443 | return 0; | |
1444 | } | |
1da177e4 LT |
1445 | #endif |
1446 | ||
1447 | static int nfs_flush_inode(struct inode *inode, unsigned long idx_start, | |
1448 | unsigned int npages, int how) | |
1449 | { | |
1450 | struct nfs_inode *nfsi = NFS_I(inode); | |
1451 | LIST_HEAD(head); | |
7d46a49f | 1452 | int res; |
1da177e4 LT |
1453 | |
1454 | spin_lock(&nfsi->req_lock); | |
1455 | res = nfs_scan_dirty(inode, &head, idx_start, npages); | |
1456 | spin_unlock(&nfsi->req_lock); | |
ab0a3dbe | 1457 | if (res) { |
7d46a49f TM |
1458 | int error = nfs_flush_list(inode, &head, res, how); |
1459 | if (error < 0) | |
1460 | return error; | |
ab0a3dbe | 1461 | } |
1da177e4 LT |
1462 | return res; |
1463 | } | |
1464 | ||
1465 | #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) | |
3da28eb1 | 1466 | int nfs_commit_inode(struct inode *inode, int how) |
1da177e4 LT |
1467 | { |
1468 | struct nfs_inode *nfsi = NFS_I(inode); | |
1469 | LIST_HEAD(head); | |
7d46a49f | 1470 | int res; |
1da177e4 LT |
1471 | |
1472 | spin_lock(&nfsi->req_lock); | |
3da28eb1 TM |
1473 | res = nfs_scan_commit(inode, &head, 0, 0); |
1474 | spin_unlock(&nfsi->req_lock); | |
1da177e4 | 1475 | if (res) { |
7d46a49f | 1476 | int error = nfs_commit_list(inode, &head, how); |
3da28eb1 TM |
1477 | if (error < 0) |
1478 | return error; | |
1479 | } | |
1da177e4 LT |
1480 | return res; |
1481 | } | |
1482 | #endif | |
1483 | ||
c42de9dd TM |
1484 | int nfs_sync_inode_wait(struct inode *inode, unsigned long idx_start, |
1485 | unsigned int npages, int how) | |
1da177e4 | 1486 | { |
c42de9dd TM |
1487 | struct nfs_inode *nfsi = NFS_I(inode); |
1488 | LIST_HEAD(head); | |
70b9ecbd | 1489 | int nocommit = how & FLUSH_NOCOMMIT; |
c42de9dd | 1490 | int pages, ret; |
1da177e4 | 1491 | |
c42de9dd TM |
1492 | how &= ~FLUSH_NOCOMMIT; |
1493 | spin_lock(&nfsi->req_lock); | |
1da177e4 | 1494 | do { |
c42de9dd TM |
1495 | ret = nfs_wait_on_requests_locked(inode, idx_start, npages); |
1496 | if (ret != 0) | |
70b9ecbd | 1497 | continue; |
c42de9dd TM |
1498 | pages = nfs_scan_dirty(inode, &head, idx_start, npages); |
1499 | if (pages != 0) { | |
1500 | spin_unlock(&nfsi->req_lock); | |
d2ccddf0 TM |
1501 | if (how & FLUSH_INVALIDATE) |
1502 | nfs_cancel_requests(&head); | |
1503 | else | |
1504 | ret = nfs_flush_list(inode, &head, pages, how); | |
c42de9dd TM |
1505 | spin_lock(&nfsi->req_lock); |
1506 | continue; | |
1507 | } | |
1508 | if (nocommit) | |
1509 | break; | |
d2ccddf0 | 1510 | pages = nfs_scan_commit(inode, &head, idx_start, npages); |
c42de9dd TM |
1511 | if (pages == 0) |
1512 | break; | |
d2ccddf0 TM |
1513 | if (how & FLUSH_INVALIDATE) { |
1514 | spin_unlock(&nfsi->req_lock); | |
1515 | nfs_cancel_requests(&head); | |
1516 | spin_lock(&nfsi->req_lock); | |
1517 | continue; | |
1518 | } | |
1519 | pages += nfs_scan_commit(inode, &head, 0, 0); | |
c42de9dd TM |
1520 | spin_unlock(&nfsi->req_lock); |
1521 | ret = nfs_commit_list(inode, &head, how); | |
1522 | spin_lock(&nfsi->req_lock); | |
1523 | } while (ret >= 0); | |
1524 | spin_unlock(&nfsi->req_lock); | |
1525 | return ret; | |
1da177e4 LT |
1526 | } |
1527 | ||
f7b422b1 | 1528 | int __init nfs_init_writepagecache(void) |
1da177e4 LT |
1529 | { |
1530 | nfs_wdata_cachep = kmem_cache_create("nfs_write_data", | |
1531 | sizeof(struct nfs_write_data), | |
1532 | 0, SLAB_HWCACHE_ALIGN, | |
1533 | NULL, NULL); | |
1534 | if (nfs_wdata_cachep == NULL) | |
1535 | return -ENOMEM; | |
1536 | ||
93d2341c MD |
1537 | nfs_wdata_mempool = mempool_create_slab_pool(MIN_POOL_WRITE, |
1538 | nfs_wdata_cachep); | |
1da177e4 LT |
1539 | if (nfs_wdata_mempool == NULL) |
1540 | return -ENOMEM; | |
1541 | ||
93d2341c MD |
1542 | nfs_commit_mempool = mempool_create_slab_pool(MIN_POOL_COMMIT, |
1543 | nfs_wdata_cachep); | |
1da177e4 LT |
1544 | if (nfs_commit_mempool == NULL) |
1545 | return -ENOMEM; | |
1546 | ||
1547 | return 0; | |
1548 | } | |
1549 | ||
266bee88 | 1550 | void nfs_destroy_writepagecache(void) |
1da177e4 LT |
1551 | { |
1552 | mempool_destroy(nfs_commit_mempool); | |
1553 | mempool_destroy(nfs_wdata_mempool); | |
1554 | if (kmem_cache_destroy(nfs_wdata_cachep)) | |
1555 | printk(KERN_INFO "nfs_write_data: not all structures were freed\n"); | |
1556 | } | |
1557 |