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Commit | Line | Data |
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08e0e7c8 | 1 | /* AFS filesystem file handling |
1da177e4 | 2 | * |
08e0e7c8 | 3 | * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved. |
1da177e4 LT |
4 | * Written by David Howells (dhowells@redhat.com) |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | */ | |
11 | ||
12 | #include <linux/kernel.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/init.h> | |
1da177e4 LT |
15 | #include <linux/fs.h> |
16 | #include <linux/pagemap.h> | |
31143d5d | 17 | #include <linux/writeback.h> |
5a0e3ad6 | 18 | #include <linux/gfp.h> |
91b467e0 | 19 | #include <linux/task_io_accounting_ops.h> |
1da177e4 LT |
20 | #include "internal.h" |
21 | ||
1cf7a151 | 22 | static int afs_file_mmap(struct file *file, struct vm_area_struct *vma); |
416351f2 | 23 | static int afs_readpage(struct file *file, struct page *page); |
d47992f8 LC |
24 | static void afs_invalidatepage(struct page *page, unsigned int offset, |
25 | unsigned int length); | |
416351f2 | 26 | static int afs_releasepage(struct page *page, gfp_t gfp_flags); |
1da177e4 | 27 | |
9b3f26c9 DH |
28 | static int afs_readpages(struct file *filp, struct address_space *mapping, |
29 | struct list_head *pages, unsigned nr_pages); | |
30 | ||
00d3b7a4 DH |
31 | const struct file_operations afs_file_operations = { |
32 | .open = afs_open, | |
58fed94d | 33 | .flush = afs_flush, |
00d3b7a4 DH |
34 | .release = afs_release, |
35 | .llseek = generic_file_llseek, | |
aad4f8bb | 36 | .read_iter = generic_file_read_iter, |
50b5551d | 37 | .write_iter = afs_file_write, |
1cf7a151 | 38 | .mmap = afs_file_mmap, |
5ffc4ef4 | 39 | .splice_read = generic_file_splice_read, |
31143d5d | 40 | .fsync = afs_fsync, |
e8d6c554 DH |
41 | .lock = afs_lock, |
42 | .flock = afs_flock, | |
00d3b7a4 DH |
43 | }; |
44 | ||
754661f1 | 45 | const struct inode_operations afs_file_inode_operations = { |
416351f2 | 46 | .getattr = afs_getattr, |
31143d5d | 47 | .setattr = afs_setattr, |
00d3b7a4 | 48 | .permission = afs_permission, |
d3e3b7ea | 49 | .listxattr = afs_listxattr, |
1da177e4 LT |
50 | }; |
51 | ||
f5e54d6e | 52 | const struct address_space_operations afs_fs_aops = { |
416351f2 | 53 | .readpage = afs_readpage, |
9b3f26c9 | 54 | .readpages = afs_readpages, |
31143d5d DH |
55 | .set_page_dirty = afs_set_page_dirty, |
56 | .launder_page = afs_launder_page, | |
416351f2 DH |
57 | .releasepage = afs_releasepage, |
58 | .invalidatepage = afs_invalidatepage, | |
15b4650e NP |
59 | .write_begin = afs_write_begin, |
60 | .write_end = afs_write_end, | |
31143d5d DH |
61 | .writepage = afs_writepage, |
62 | .writepages = afs_writepages, | |
1da177e4 LT |
63 | }; |
64 | ||
1cf7a151 DH |
65 | static const struct vm_operations_struct afs_vm_ops = { |
66 | .fault = filemap_fault, | |
67 | .map_pages = filemap_map_pages, | |
68 | .page_mkwrite = afs_page_mkwrite, | |
69 | }; | |
70 | ||
4343d008 DH |
71 | /* |
72 | * Discard a pin on a writeback key. | |
73 | */ | |
74 | void afs_put_wb_key(struct afs_wb_key *wbk) | |
75 | { | |
76 | if (refcount_dec_and_test(&wbk->usage)) { | |
77 | key_put(wbk->key); | |
78 | kfree(wbk); | |
79 | } | |
80 | } | |
81 | ||
82 | /* | |
83 | * Cache key for writeback. | |
84 | */ | |
85 | int afs_cache_wb_key(struct afs_vnode *vnode, struct afs_file *af) | |
86 | { | |
87 | struct afs_wb_key *wbk, *p; | |
88 | ||
89 | wbk = kzalloc(sizeof(struct afs_wb_key), GFP_KERNEL); | |
90 | if (!wbk) | |
91 | return -ENOMEM; | |
92 | refcount_set(&wbk->usage, 2); | |
93 | wbk->key = af->key; | |
94 | ||
95 | spin_lock(&vnode->wb_lock); | |
96 | list_for_each_entry(p, &vnode->wb_keys, vnode_link) { | |
97 | if (p->key == wbk->key) | |
98 | goto found; | |
99 | } | |
100 | ||
101 | key_get(wbk->key); | |
102 | list_add_tail(&wbk->vnode_link, &vnode->wb_keys); | |
103 | spin_unlock(&vnode->wb_lock); | |
104 | af->wb = wbk; | |
105 | return 0; | |
106 | ||
107 | found: | |
108 | refcount_inc(&p->usage); | |
109 | spin_unlock(&vnode->wb_lock); | |
110 | af->wb = p; | |
111 | kfree(wbk); | |
112 | return 0; | |
113 | } | |
114 | ||
00d3b7a4 DH |
115 | /* |
116 | * open an AFS file or directory and attach a key to it | |
117 | */ | |
118 | int afs_open(struct inode *inode, struct file *file) | |
119 | { | |
120 | struct afs_vnode *vnode = AFS_FS_I(inode); | |
215804a9 | 121 | struct afs_file *af; |
00d3b7a4 | 122 | struct key *key; |
260a9803 | 123 | int ret; |
00d3b7a4 | 124 | |
416351f2 | 125 | _enter("{%x:%u},", vnode->fid.vid, vnode->fid.vnode); |
00d3b7a4 DH |
126 | |
127 | key = afs_request_key(vnode->volume->cell); | |
128 | if (IS_ERR(key)) { | |
215804a9 DH |
129 | ret = PTR_ERR(key); |
130 | goto error; | |
00d3b7a4 DH |
131 | } |
132 | ||
215804a9 DH |
133 | af = kzalloc(sizeof(*af), GFP_KERNEL); |
134 | if (!af) { | |
135 | ret = -ENOMEM; | |
136 | goto error_key; | |
260a9803 | 137 | } |
4343d008 | 138 | af->key = key; |
260a9803 | 139 | |
215804a9 DH |
140 | ret = afs_validate(vnode, key); |
141 | if (ret < 0) | |
142 | goto error_af; | |
143 | ||
4343d008 DH |
144 | if (file->f_mode & FMODE_WRITE) { |
145 | ret = afs_cache_wb_key(vnode, af); | |
146 | if (ret < 0) | |
147 | goto error_af; | |
148 | } | |
149 | ||
215804a9 | 150 | file->private_data = af; |
00d3b7a4 DH |
151 | _leave(" = 0"); |
152 | return 0; | |
215804a9 DH |
153 | |
154 | error_af: | |
155 | kfree(af); | |
156 | error_key: | |
157 | key_put(key); | |
158 | error: | |
159 | _leave(" = %d", ret); | |
160 | return ret; | |
00d3b7a4 DH |
161 | } |
162 | ||
163 | /* | |
164 | * release an AFS file or directory and discard its key | |
165 | */ | |
166 | int afs_release(struct inode *inode, struct file *file) | |
167 | { | |
168 | struct afs_vnode *vnode = AFS_FS_I(inode); | |
215804a9 | 169 | struct afs_file *af = file->private_data; |
00d3b7a4 | 170 | |
416351f2 | 171 | _enter("{%x:%u},", vnode->fid.vid, vnode->fid.vnode); |
00d3b7a4 | 172 | |
215804a9 | 173 | file->private_data = NULL; |
4343d008 DH |
174 | if (af->wb) |
175 | afs_put_wb_key(af->wb); | |
215804a9 DH |
176 | key_put(af->key); |
177 | kfree(af); | |
4343d008 | 178 | afs_prune_wb_keys(vnode); |
00d3b7a4 DH |
179 | _leave(" = 0"); |
180 | return 0; | |
181 | } | |
182 | ||
196ee9cd DH |
183 | /* |
184 | * Dispose of a ref to a read record. | |
185 | */ | |
186 | void afs_put_read(struct afs_read *req) | |
187 | { | |
188 | int i; | |
189 | ||
190 | if (atomic_dec_and_test(&req->usage)) { | |
191 | for (i = 0; i < req->nr_pages; i++) | |
192 | if (req->pages[i]) | |
193 | put_page(req->pages[i]); | |
194 | kfree(req); | |
195 | } | |
196 | } | |
197 | ||
6566abdb | 198 | #ifdef CONFIG_AFS_FSCACHE |
1da177e4 LT |
199 | /* |
200 | * deal with notification that a page was read from the cache | |
201 | */ | |
9b3f26c9 DH |
202 | static void afs_file_readpage_read_complete(struct page *page, |
203 | void *data, | |
204 | int error) | |
1da177e4 | 205 | { |
9b3f26c9 | 206 | _enter("%p,%p,%d", page, data, error); |
1da177e4 | 207 | |
9b3f26c9 DH |
208 | /* if the read completes with an error, we just unlock the page and let |
209 | * the VM reissue the readpage */ | |
210 | if (!error) | |
1da177e4 LT |
211 | SetPageUptodate(page); |
212 | unlock_page(page); | |
ec26815a | 213 | } |
6566abdb | 214 | #endif |
1da177e4 | 215 | |
d2ddc776 DH |
216 | /* |
217 | * Fetch file data from the volume. | |
218 | */ | |
219 | int afs_fetch_data(struct afs_vnode *vnode, struct key *key, struct afs_read *desc) | |
220 | { | |
221 | struct afs_fs_cursor fc; | |
222 | int ret; | |
223 | ||
224 | _enter("%s{%x:%u.%u},%x,,,", | |
225 | vnode->volume->name, | |
226 | vnode->fid.vid, | |
227 | vnode->fid.vnode, | |
228 | vnode->fid.unique, | |
229 | key_serial(key)); | |
230 | ||
231 | ret = -ERESTARTSYS; | |
232 | if (afs_begin_vnode_operation(&fc, vnode, key)) { | |
233 | while (afs_select_fileserver(&fc)) { | |
234 | fc.cb_break = vnode->cb_break + vnode->cb_s_break; | |
235 | afs_fs_fetch_data(&fc, desc); | |
236 | } | |
237 | ||
238 | afs_check_for_remote_deletion(&fc, fc.vnode); | |
239 | afs_vnode_commit_status(&fc, vnode, fc.cb_break); | |
240 | ret = afs_end_vnode_operation(&fc); | |
241 | } | |
242 | ||
243 | _leave(" = %d", ret); | |
244 | return ret; | |
245 | } | |
246 | ||
1da177e4 | 247 | /* |
f6d335c0 | 248 | * read page from file, directory or symlink, given a key to use |
1da177e4 | 249 | */ |
f6d335c0 | 250 | int afs_page_filler(void *data, struct page *page) |
1da177e4 | 251 | { |
f6d335c0 AV |
252 | struct inode *inode = page->mapping->host; |
253 | struct afs_vnode *vnode = AFS_FS_I(inode); | |
196ee9cd | 254 | struct afs_read *req; |
f6d335c0 | 255 | struct key *key = data; |
1da177e4 LT |
256 | int ret; |
257 | ||
00d3b7a4 | 258 | _enter("{%x},{%lu},{%lu}", key_serial(key), inode->i_ino, page->index); |
1da177e4 | 259 | |
cd7619d6 | 260 | BUG_ON(!PageLocked(page)); |
1da177e4 LT |
261 | |
262 | ret = -ESTALE; | |
08e0e7c8 | 263 | if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) |
1da177e4 LT |
264 | goto error; |
265 | ||
1da177e4 | 266 | /* is it cached? */ |
9b3f26c9 DH |
267 | #ifdef CONFIG_AFS_FSCACHE |
268 | ret = fscache_read_or_alloc_page(vnode->cache, | |
1da177e4 LT |
269 | page, |
270 | afs_file_readpage_read_complete, | |
271 | NULL, | |
272 | GFP_KERNEL); | |
273 | #else | |
274 | ret = -ENOBUFS; | |
275 | #endif | |
1da177e4 | 276 | switch (ret) { |
1da177e4 LT |
277 | /* read BIO submitted (page in cache) */ |
278 | case 0: | |
279 | break; | |
280 | ||
9b3f26c9 | 281 | /* page not yet cached */ |
1da177e4 | 282 | case -ENODATA: |
9b3f26c9 DH |
283 | _debug("cache said ENODATA"); |
284 | goto go_on; | |
285 | ||
286 | /* page will not be cached */ | |
287 | case -ENOBUFS: | |
288 | _debug("cache said ENOBUFS"); | |
1da177e4 | 289 | default: |
9b3f26c9 | 290 | go_on: |
196ee9cd DH |
291 | req = kzalloc(sizeof(struct afs_read) + sizeof(struct page *), |
292 | GFP_KERNEL); | |
293 | if (!req) | |
294 | goto enomem; | |
295 | ||
6db3ac3c DH |
296 | /* We request a full page. If the page is a partial one at the |
297 | * end of the file, the server will return a short read and the | |
298 | * unmarshalling code will clear the unfilled space. | |
299 | */ | |
196ee9cd DH |
300 | atomic_set(&req->usage, 1); |
301 | req->pos = (loff_t)page->index << PAGE_SHIFT; | |
6db3ac3c | 302 | req->len = PAGE_SIZE; |
196ee9cd DH |
303 | req->nr_pages = 1; |
304 | req->pages[0] = page; | |
305 | get_page(page); | |
1da177e4 LT |
306 | |
307 | /* read the contents of the file from the server into the | |
308 | * page */ | |
d2ddc776 | 309 | ret = afs_fetch_data(vnode, key, req); |
196ee9cd | 310 | afs_put_read(req); |
dab17c1a DH |
311 | |
312 | if (ret >= 0 && S_ISDIR(inode->i_mode) && | |
313 | !afs_dir_check_page(inode, page)) | |
314 | ret = -EIO; | |
315 | ||
1da177e4 | 316 | if (ret < 0) { |
08e0e7c8 | 317 | if (ret == -ENOENT) { |
1da177e4 LT |
318 | _debug("got NOENT from server" |
319 | " - marking file deleted and stale"); | |
08e0e7c8 | 320 | set_bit(AFS_VNODE_DELETED, &vnode->flags); |
1da177e4 LT |
321 | ret = -ESTALE; |
322 | } | |
9b3f26c9 DH |
323 | |
324 | #ifdef CONFIG_AFS_FSCACHE | |
325 | fscache_uncache_page(vnode->cache, page); | |
1da177e4 | 326 | #endif |
9b3f26c9 | 327 | BUG_ON(PageFsCache(page)); |
68ae849d DH |
328 | |
329 | if (ret == -EINTR || | |
330 | ret == -ENOMEM || | |
331 | ret == -ERESTARTSYS || | |
332 | ret == -EAGAIN) | |
333 | goto error; | |
334 | goto io_error; | |
1da177e4 LT |
335 | } |
336 | ||
337 | SetPageUptodate(page); | |
338 | ||
9b3f26c9 DH |
339 | /* send the page to the cache */ |
340 | #ifdef CONFIG_AFS_FSCACHE | |
341 | if (PageFsCache(page) && | |
342 | fscache_write_page(vnode->cache, page, GFP_KERNEL) != 0) { | |
343 | fscache_uncache_page(vnode->cache, page); | |
344 | BUG_ON(PageFsCache(page)); | |
1da177e4 | 345 | } |
1da177e4 | 346 | #endif |
9b3f26c9 | 347 | unlock_page(page); |
1da177e4 LT |
348 | } |
349 | ||
350 | _leave(" = 0"); | |
351 | return 0; | |
352 | ||
68ae849d DH |
353 | io_error: |
354 | SetPageError(page); | |
355 | goto error; | |
196ee9cd DH |
356 | enomem: |
357 | ret = -ENOMEM; | |
08e0e7c8 | 358 | error: |
1da177e4 | 359 | unlock_page(page); |
1da177e4 LT |
360 | _leave(" = %d", ret); |
361 | return ret; | |
ec26815a | 362 | } |
1da177e4 | 363 | |
f6d335c0 AV |
364 | /* |
365 | * read page from file, directory or symlink, given a file to nominate the key | |
366 | * to be used | |
367 | */ | |
368 | static int afs_readpage(struct file *file, struct page *page) | |
369 | { | |
370 | struct key *key; | |
371 | int ret; | |
372 | ||
373 | if (file) { | |
215804a9 | 374 | key = afs_file_key(file); |
f6d335c0 AV |
375 | ASSERT(key != NULL); |
376 | ret = afs_page_filler(key, page); | |
377 | } else { | |
378 | struct inode *inode = page->mapping->host; | |
d2ddc776 | 379 | key = afs_request_key(AFS_FS_S(inode->i_sb)->cell); |
f6d335c0 AV |
380 | if (IS_ERR(key)) { |
381 | ret = PTR_ERR(key); | |
382 | } else { | |
383 | ret = afs_page_filler(key, page); | |
384 | key_put(key); | |
385 | } | |
386 | } | |
387 | return ret; | |
388 | } | |
389 | ||
91b467e0 DH |
390 | /* |
391 | * Make pages available as they're filled. | |
392 | */ | |
393 | static void afs_readpages_page_done(struct afs_call *call, struct afs_read *req) | |
394 | { | |
51c89e6a | 395 | #ifdef CONFIG_AFS_FSCACHE |
97e3043a | 396 | struct afs_vnode *vnode = call->reply[0]; |
51c89e6a | 397 | #endif |
91b467e0 DH |
398 | struct page *page = req->pages[req->index]; |
399 | ||
400 | req->pages[req->index] = NULL; | |
401 | SetPageUptodate(page); | |
402 | ||
403 | /* send the page to the cache */ | |
404 | #ifdef CONFIG_AFS_FSCACHE | |
405 | if (PageFsCache(page) && | |
406 | fscache_write_page(vnode->cache, page, GFP_KERNEL) != 0) { | |
407 | fscache_uncache_page(vnode->cache, page); | |
408 | BUG_ON(PageFsCache(page)); | |
409 | } | |
410 | #endif | |
411 | unlock_page(page); | |
412 | put_page(page); | |
413 | } | |
414 | ||
415 | /* | |
416 | * Read a contiguous set of pages. | |
417 | */ | |
418 | static int afs_readpages_one(struct file *file, struct address_space *mapping, | |
419 | struct list_head *pages) | |
420 | { | |
421 | struct afs_vnode *vnode = AFS_FS_I(mapping->host); | |
422 | struct afs_read *req; | |
423 | struct list_head *p; | |
424 | struct page *first, *page; | |
215804a9 | 425 | struct key *key = afs_file_key(file); |
91b467e0 DH |
426 | pgoff_t index; |
427 | int ret, n, i; | |
428 | ||
429 | /* Count the number of contiguous pages at the front of the list. Note | |
430 | * that the list goes prev-wards rather than next-wards. | |
431 | */ | |
432 | first = list_entry(pages->prev, struct page, lru); | |
433 | index = first->index + 1; | |
434 | n = 1; | |
435 | for (p = first->lru.prev; p != pages; p = p->prev) { | |
436 | page = list_entry(p, struct page, lru); | |
437 | if (page->index != index) | |
438 | break; | |
439 | index++; | |
440 | n++; | |
441 | } | |
442 | ||
443 | req = kzalloc(sizeof(struct afs_read) + sizeof(struct page *) * n, | |
444 | GFP_NOFS); | |
445 | if (!req) | |
446 | return -ENOMEM; | |
447 | ||
448 | atomic_set(&req->usage, 1); | |
449 | req->page_done = afs_readpages_page_done; | |
450 | req->pos = first->index; | |
451 | req->pos <<= PAGE_SHIFT; | |
452 | ||
453 | /* Transfer the pages to the request. We add them in until one fails | |
454 | * to add to the LRU and then we stop (as that'll make a hole in the | |
455 | * contiguous run. | |
456 | * | |
457 | * Note that it's possible for the file size to change whilst we're | |
458 | * doing this, but we rely on the server returning less than we asked | |
459 | * for if the file shrank. We also rely on this to deal with a partial | |
460 | * page at the end of the file. | |
461 | */ | |
462 | do { | |
463 | page = list_entry(pages->prev, struct page, lru); | |
464 | list_del(&page->lru); | |
465 | index = page->index; | |
466 | if (add_to_page_cache_lru(page, mapping, index, | |
467 | readahead_gfp_mask(mapping))) { | |
468 | #ifdef CONFIG_AFS_FSCACHE | |
469 | fscache_uncache_page(vnode->cache, page); | |
470 | #endif | |
471 | put_page(page); | |
472 | break; | |
473 | } | |
474 | ||
475 | req->pages[req->nr_pages++] = page; | |
476 | req->len += PAGE_SIZE; | |
477 | } while (req->nr_pages < n); | |
478 | ||
479 | if (req->nr_pages == 0) { | |
480 | kfree(req); | |
481 | return 0; | |
482 | } | |
483 | ||
d2ddc776 | 484 | ret = afs_fetch_data(vnode, key, req); |
91b467e0 DH |
485 | if (ret < 0) |
486 | goto error; | |
487 | ||
488 | task_io_account_read(PAGE_SIZE * req->nr_pages); | |
489 | afs_put_read(req); | |
490 | return 0; | |
491 | ||
492 | error: | |
493 | if (ret == -ENOENT) { | |
494 | _debug("got NOENT from server" | |
495 | " - marking file deleted and stale"); | |
496 | set_bit(AFS_VNODE_DELETED, &vnode->flags); | |
497 | ret = -ESTALE; | |
498 | } | |
499 | ||
500 | for (i = 0; i < req->nr_pages; i++) { | |
501 | page = req->pages[i]; | |
502 | if (page) { | |
503 | #ifdef CONFIG_AFS_FSCACHE | |
504 | fscache_uncache_page(vnode->cache, page); | |
505 | #endif | |
506 | SetPageError(page); | |
507 | unlock_page(page); | |
508 | } | |
509 | } | |
510 | ||
511 | afs_put_read(req); | |
512 | return ret; | |
513 | } | |
514 | ||
1da177e4 | 515 | /* |
9b3f26c9 | 516 | * read a set of pages |
1da177e4 | 517 | */ |
9b3f26c9 DH |
518 | static int afs_readpages(struct file *file, struct address_space *mapping, |
519 | struct list_head *pages, unsigned nr_pages) | |
1da177e4 | 520 | { |
215804a9 | 521 | struct key *key = afs_file_key(file); |
9b3f26c9 DH |
522 | struct afs_vnode *vnode; |
523 | int ret = 0; | |
1da177e4 | 524 | |
f6d335c0 AV |
525 | _enter("{%d},{%lu},,%d", |
526 | key_serial(key), mapping->host->i_ino, nr_pages); | |
527 | ||
528 | ASSERT(key != NULL); | |
1da177e4 | 529 | |
9b3f26c9 | 530 | vnode = AFS_FS_I(mapping->host); |
ad2a8e60 | 531 | if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) { |
9b3f26c9 DH |
532 | _leave(" = -ESTALE"); |
533 | return -ESTALE; | |
534 | } | |
1da177e4 | 535 | |
9b3f26c9 DH |
536 | /* attempt to read as many of the pages as possible */ |
537 | #ifdef CONFIG_AFS_FSCACHE | |
538 | ret = fscache_read_or_alloc_pages(vnode->cache, | |
539 | mapping, | |
540 | pages, | |
541 | &nr_pages, | |
542 | afs_file_readpage_read_complete, | |
543 | NULL, | |
544 | mapping_gfp_mask(mapping)); | |
545 | #else | |
546 | ret = -ENOBUFS; | |
547 | #endif | |
548 | ||
549 | switch (ret) { | |
550 | /* all pages are being read from the cache */ | |
551 | case 0: | |
552 | BUG_ON(!list_empty(pages)); | |
553 | BUG_ON(nr_pages != 0); | |
554 | _leave(" = 0 [reading all]"); | |
555 | return 0; | |
556 | ||
557 | /* there were pages that couldn't be read from the cache */ | |
558 | case -ENODATA: | |
559 | case -ENOBUFS: | |
560 | break; | |
561 | ||
562 | /* other error */ | |
563 | default: | |
564 | _leave(" = %d", ret); | |
565 | return ret; | |
1da177e4 LT |
566 | } |
567 | ||
91b467e0 DH |
568 | while (!list_empty(pages)) { |
569 | ret = afs_readpages_one(file, mapping, pages); | |
570 | if (ret < 0) | |
571 | break; | |
572 | } | |
9b3f26c9 DH |
573 | |
574 | _leave(" = %d [netting]", ret); | |
575 | return ret; | |
ec26815a | 576 | } |
1da177e4 | 577 | |
1da177e4 | 578 | /* |
9b3f26c9 DH |
579 | * invalidate part or all of a page |
580 | * - release a page and clean up its private data if offset is 0 (indicating | |
581 | * the entire page) | |
582 | */ | |
d47992f8 LC |
583 | static void afs_invalidatepage(struct page *page, unsigned int offset, |
584 | unsigned int length) | |
9b3f26c9 | 585 | { |
d47992f8 | 586 | _enter("{%lu},%u,%u", page->index, offset, length); |
9b3f26c9 DH |
587 | |
588 | BUG_ON(!PageLocked(page)); | |
589 | ||
590 | /* we clean up only if the entire page is being invalidated */ | |
09cbfeaf | 591 | if (offset == 0 && length == PAGE_SIZE) { |
9b3f26c9 DH |
592 | #ifdef CONFIG_AFS_FSCACHE |
593 | if (PageFsCache(page)) { | |
594 | struct afs_vnode *vnode = AFS_FS_I(page->mapping->host); | |
595 | fscache_wait_on_page_write(vnode->cache, page); | |
596 | fscache_uncache_page(vnode->cache, page); | |
9b3f26c9 DH |
597 | } |
598 | #endif | |
599 | ||
600 | if (PagePrivate(page)) { | |
4343d008 DH |
601 | set_page_private(page, 0); |
602 | ClearPagePrivate(page); | |
9b3f26c9 DH |
603 | } |
604 | } | |
605 | ||
606 | _leave(""); | |
607 | } | |
608 | ||
609 | /* | |
610 | * release a page and clean up its private state if it's not busy | |
611 | * - return true if the page can now be released, false if not | |
1da177e4 | 612 | */ |
416351f2 | 613 | static int afs_releasepage(struct page *page, gfp_t gfp_flags) |
1da177e4 | 614 | { |
416351f2 | 615 | struct afs_vnode *vnode = AFS_FS_I(page->mapping->host); |
1da177e4 | 616 | |
416351f2 DH |
617 | _enter("{{%x:%u}[%lu],%lx},%x", |
618 | vnode->fid.vid, vnode->fid.vnode, page->index, page->flags, | |
619 | gfp_flags); | |
1da177e4 | 620 | |
9b3f26c9 DH |
621 | /* deny if page is being written to the cache and the caller hasn't |
622 | * elected to wait */ | |
623 | #ifdef CONFIG_AFS_FSCACHE | |
201a1542 DH |
624 | if (!fscache_maybe_release_page(vnode->cache, page, gfp_flags)) { |
625 | _leave(" = F [cache busy]"); | |
626 | return 0; | |
9b3f26c9 DH |
627 | } |
628 | #endif | |
629 | ||
1da177e4 | 630 | if (PagePrivate(page)) { |
4343d008 | 631 | set_page_private(page, 0); |
1da177e4 | 632 | ClearPagePrivate(page); |
1da177e4 LT |
633 | } |
634 | ||
9b3f26c9 DH |
635 | /* indicate that the page can be released */ |
636 | _leave(" = T"); | |
637 | return 1; | |
ec26815a | 638 | } |
1cf7a151 DH |
639 | |
640 | /* | |
641 | * Handle setting up a memory mapping on an AFS file. | |
642 | */ | |
643 | static int afs_file_mmap(struct file *file, struct vm_area_struct *vma) | |
644 | { | |
645 | int ret; | |
646 | ||
647 | ret = generic_file_mmap(file, vma); | |
648 | if (ret == 0) | |
649 | vma->vm_ops = &afs_vm_ops; | |
650 | return ret; | |
651 | } |