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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> |
f86196ea | 20 | #include <linux/mm.h> |
1da177e4 LT |
21 | #include "internal.h" |
22 | ||
1cf7a151 | 23 | static int afs_file_mmap(struct file *file, struct vm_area_struct *vma); |
416351f2 | 24 | static int afs_readpage(struct file *file, struct page *page); |
d47992f8 LC |
25 | static void afs_invalidatepage(struct page *page, unsigned int offset, |
26 | unsigned int length); | |
416351f2 | 27 | static int afs_releasepage(struct page *page, gfp_t gfp_flags); |
1da177e4 | 28 | |
9b3f26c9 DH |
29 | static int afs_readpages(struct file *filp, struct address_space *mapping, |
30 | struct list_head *pages, unsigned nr_pages); | |
31 | ||
00d3b7a4 DH |
32 | const struct file_operations afs_file_operations = { |
33 | .open = afs_open, | |
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 | |
3b6492df | 125 | _enter("{%llx:%llu},", 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 | } | |
5a813276 DH |
149 | |
150 | if (file->f_flags & O_TRUNC) | |
151 | set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags); | |
4343d008 | 152 | |
215804a9 | 153 | file->private_data = af; |
00d3b7a4 DH |
154 | _leave(" = 0"); |
155 | return 0; | |
215804a9 DH |
156 | |
157 | error_af: | |
158 | kfree(af); | |
159 | error_key: | |
160 | key_put(key); | |
161 | error: | |
162 | _leave(" = %d", ret); | |
163 | return ret; | |
00d3b7a4 DH |
164 | } |
165 | ||
166 | /* | |
167 | * release an AFS file or directory and discard its key | |
168 | */ | |
169 | int afs_release(struct inode *inode, struct file *file) | |
170 | { | |
171 | struct afs_vnode *vnode = AFS_FS_I(inode); | |
215804a9 | 172 | struct afs_file *af = file->private_data; |
a1b879ee | 173 | int ret = 0; |
00d3b7a4 | 174 | |
3b6492df | 175 | _enter("{%llx:%llu},", vnode->fid.vid, vnode->fid.vnode); |
00d3b7a4 | 176 | |
5a813276 | 177 | if ((file->f_mode & FMODE_WRITE)) |
a1b879ee | 178 | ret = vfs_fsync(file, 0); |
5a813276 | 179 | |
215804a9 | 180 | file->private_data = NULL; |
4343d008 DH |
181 | if (af->wb) |
182 | afs_put_wb_key(af->wb); | |
215804a9 DH |
183 | key_put(af->key); |
184 | kfree(af); | |
4343d008 | 185 | afs_prune_wb_keys(vnode); |
a1b879ee DH |
186 | _leave(" = %d", ret); |
187 | return ret; | |
00d3b7a4 DH |
188 | } |
189 | ||
196ee9cd DH |
190 | /* |
191 | * Dispose of a ref to a read record. | |
192 | */ | |
193 | void afs_put_read(struct afs_read *req) | |
194 | { | |
195 | int i; | |
196 | ||
f3ddee8d | 197 | if (refcount_dec_and_test(&req->usage)) { |
196ee9cd DH |
198 | for (i = 0; i < req->nr_pages; i++) |
199 | if (req->pages[i]) | |
200 | put_page(req->pages[i]); | |
f3ddee8d DH |
201 | if (req->pages != req->array) |
202 | kfree(req->pages); | |
196ee9cd DH |
203 | kfree(req); |
204 | } | |
205 | } | |
206 | ||
6566abdb | 207 | #ifdef CONFIG_AFS_FSCACHE |
1da177e4 LT |
208 | /* |
209 | * deal with notification that a page was read from the cache | |
210 | */ | |
9b3f26c9 DH |
211 | static void afs_file_readpage_read_complete(struct page *page, |
212 | void *data, | |
213 | int error) | |
1da177e4 | 214 | { |
9b3f26c9 | 215 | _enter("%p,%p,%d", page, data, error); |
1da177e4 | 216 | |
9b3f26c9 DH |
217 | /* if the read completes with an error, we just unlock the page and let |
218 | * the VM reissue the readpage */ | |
219 | if (!error) | |
1da177e4 LT |
220 | SetPageUptodate(page); |
221 | unlock_page(page); | |
ec26815a | 222 | } |
6566abdb | 223 | #endif |
1da177e4 | 224 | |
d2ddc776 DH |
225 | /* |
226 | * Fetch file data from the volume. | |
227 | */ | |
228 | int afs_fetch_data(struct afs_vnode *vnode, struct key *key, struct afs_read *desc) | |
229 | { | |
230 | struct afs_fs_cursor fc; | |
a58823ac | 231 | struct afs_status_cb *scb; |
d2ddc776 DH |
232 | int ret; |
233 | ||
3b6492df | 234 | _enter("%s{%llx:%llu.%u},%x,,,", |
d2ddc776 DH |
235 | vnode->volume->name, |
236 | vnode->fid.vid, | |
237 | vnode->fid.vnode, | |
238 | vnode->fid.unique, | |
239 | key_serial(key)); | |
240 | ||
a58823ac DH |
241 | scb = kzalloc(sizeof(struct afs_status_cb), GFP_KERNEL); |
242 | if (!scb) | |
243 | return -ENOMEM; | |
244 | ||
d2ddc776 | 245 | ret = -ERESTARTSYS; |
20b8391f | 246 | if (afs_begin_vnode_operation(&fc, vnode, key, true)) { |
a58823ac DH |
247 | afs_dataversion_t data_version = vnode->status.data_version; |
248 | ||
d2ddc776 | 249 | while (afs_select_fileserver(&fc)) { |
68251f0a | 250 | fc.cb_break = afs_calc_vnode_cb_break(vnode); |
a58823ac | 251 | afs_fs_fetch_data(&fc, scb, desc); |
d2ddc776 DH |
252 | } |
253 | ||
a58823ac DH |
254 | afs_check_for_remote_deletion(&fc, vnode); |
255 | afs_vnode_commit_status(&fc, vnode, fc.cb_break, | |
256 | &data_version, scb); | |
d2ddc776 DH |
257 | ret = afs_end_vnode_operation(&fc); |
258 | } | |
259 | ||
76a5cb6f DH |
260 | if (ret == 0) { |
261 | afs_stat_v(vnode, n_fetches); | |
262 | atomic_long_add(desc->actual_len, | |
263 | &afs_v2net(vnode)->n_fetch_bytes); | |
264 | } | |
265 | ||
a58823ac | 266 | kfree(scb); |
d2ddc776 DH |
267 | _leave(" = %d", ret); |
268 | return ret; | |
269 | } | |
270 | ||
1da177e4 | 271 | /* |
f6d335c0 | 272 | * read page from file, directory or symlink, given a key to use |
1da177e4 | 273 | */ |
f6d335c0 | 274 | int afs_page_filler(void *data, struct page *page) |
1da177e4 | 275 | { |
f6d335c0 AV |
276 | struct inode *inode = page->mapping->host; |
277 | struct afs_vnode *vnode = AFS_FS_I(inode); | |
196ee9cd | 278 | struct afs_read *req; |
f6d335c0 | 279 | struct key *key = data; |
1da177e4 LT |
280 | int ret; |
281 | ||
00d3b7a4 | 282 | _enter("{%x},{%lu},{%lu}", key_serial(key), inode->i_ino, page->index); |
1da177e4 | 283 | |
cd7619d6 | 284 | BUG_ON(!PageLocked(page)); |
1da177e4 LT |
285 | |
286 | ret = -ESTALE; | |
08e0e7c8 | 287 | if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) |
1da177e4 LT |
288 | goto error; |
289 | ||
1da177e4 | 290 | /* is it cached? */ |
9b3f26c9 DH |
291 | #ifdef CONFIG_AFS_FSCACHE |
292 | ret = fscache_read_or_alloc_page(vnode->cache, | |
1da177e4 LT |
293 | page, |
294 | afs_file_readpage_read_complete, | |
295 | NULL, | |
296 | GFP_KERNEL); | |
297 | #else | |
298 | ret = -ENOBUFS; | |
299 | #endif | |
1da177e4 | 300 | switch (ret) { |
1da177e4 LT |
301 | /* read BIO submitted (page in cache) */ |
302 | case 0: | |
303 | break; | |
304 | ||
9b3f26c9 | 305 | /* page not yet cached */ |
1da177e4 | 306 | case -ENODATA: |
9b3f26c9 DH |
307 | _debug("cache said ENODATA"); |
308 | goto go_on; | |
309 | ||
310 | /* page will not be cached */ | |
311 | case -ENOBUFS: | |
312 | _debug("cache said ENOBUFS"); | |
e690c9e3 GS |
313 | |
314 | /* fall through */ | |
1da177e4 | 315 | default: |
9b3f26c9 | 316 | go_on: |
196ee9cd DH |
317 | req = kzalloc(sizeof(struct afs_read) + sizeof(struct page *), |
318 | GFP_KERNEL); | |
319 | if (!req) | |
320 | goto enomem; | |
321 | ||
6db3ac3c DH |
322 | /* We request a full page. If the page is a partial one at the |
323 | * end of the file, the server will return a short read and the | |
324 | * unmarshalling code will clear the unfilled space. | |
325 | */ | |
f3ddee8d | 326 | refcount_set(&req->usage, 1); |
196ee9cd | 327 | req->pos = (loff_t)page->index << PAGE_SHIFT; |
6db3ac3c | 328 | req->len = PAGE_SIZE; |
196ee9cd | 329 | req->nr_pages = 1; |
f3ddee8d | 330 | req->pages = req->array; |
196ee9cd DH |
331 | req->pages[0] = page; |
332 | get_page(page); | |
1da177e4 LT |
333 | |
334 | /* read the contents of the file from the server into the | |
335 | * page */ | |
d2ddc776 | 336 | ret = afs_fetch_data(vnode, key, req); |
196ee9cd | 337 | afs_put_read(req); |
dab17c1a | 338 | |
1da177e4 | 339 | if (ret < 0) { |
08e0e7c8 | 340 | if (ret == -ENOENT) { |
1da177e4 LT |
341 | _debug("got NOENT from server" |
342 | " - marking file deleted and stale"); | |
08e0e7c8 | 343 | set_bit(AFS_VNODE_DELETED, &vnode->flags); |
1da177e4 LT |
344 | ret = -ESTALE; |
345 | } | |
9b3f26c9 DH |
346 | |
347 | #ifdef CONFIG_AFS_FSCACHE | |
348 | fscache_uncache_page(vnode->cache, page); | |
1da177e4 | 349 | #endif |
9b3f26c9 | 350 | BUG_ON(PageFsCache(page)); |
68ae849d DH |
351 | |
352 | if (ret == -EINTR || | |
353 | ret == -ENOMEM || | |
354 | ret == -ERESTARTSYS || | |
355 | ret == -EAGAIN) | |
356 | goto error; | |
357 | goto io_error; | |
1da177e4 LT |
358 | } |
359 | ||
360 | SetPageUptodate(page); | |
361 | ||
9b3f26c9 DH |
362 | /* send the page to the cache */ |
363 | #ifdef CONFIG_AFS_FSCACHE | |
364 | if (PageFsCache(page) && | |
ee1235a9 DH |
365 | fscache_write_page(vnode->cache, page, vnode->status.size, |
366 | GFP_KERNEL) != 0) { | |
9b3f26c9 DH |
367 | fscache_uncache_page(vnode->cache, page); |
368 | BUG_ON(PageFsCache(page)); | |
1da177e4 | 369 | } |
1da177e4 | 370 | #endif |
9b3f26c9 | 371 | unlock_page(page); |
1da177e4 LT |
372 | } |
373 | ||
374 | _leave(" = 0"); | |
375 | return 0; | |
376 | ||
68ae849d DH |
377 | io_error: |
378 | SetPageError(page); | |
379 | goto error; | |
196ee9cd DH |
380 | enomem: |
381 | ret = -ENOMEM; | |
08e0e7c8 | 382 | error: |
1da177e4 | 383 | unlock_page(page); |
1da177e4 LT |
384 | _leave(" = %d", ret); |
385 | return ret; | |
ec26815a | 386 | } |
1da177e4 | 387 | |
f6d335c0 AV |
388 | /* |
389 | * read page from file, directory or symlink, given a file to nominate the key | |
390 | * to be used | |
391 | */ | |
392 | static int afs_readpage(struct file *file, struct page *page) | |
393 | { | |
394 | struct key *key; | |
395 | int ret; | |
396 | ||
397 | if (file) { | |
215804a9 | 398 | key = afs_file_key(file); |
f6d335c0 AV |
399 | ASSERT(key != NULL); |
400 | ret = afs_page_filler(key, page); | |
401 | } else { | |
402 | struct inode *inode = page->mapping->host; | |
d2ddc776 | 403 | key = afs_request_key(AFS_FS_S(inode->i_sb)->cell); |
f6d335c0 AV |
404 | if (IS_ERR(key)) { |
405 | ret = PTR_ERR(key); | |
406 | } else { | |
407 | ret = afs_page_filler(key, page); | |
408 | key_put(key); | |
409 | } | |
410 | } | |
411 | return ret; | |
412 | } | |
413 | ||
91b467e0 DH |
414 | /* |
415 | * Make pages available as they're filled. | |
416 | */ | |
a58823ac | 417 | static void afs_readpages_page_done(struct afs_read *req) |
91b467e0 | 418 | { |
51c89e6a | 419 | #ifdef CONFIG_AFS_FSCACHE |
a58823ac | 420 | struct afs_vnode *vnode = req->vnode; |
51c89e6a | 421 | #endif |
91b467e0 DH |
422 | struct page *page = req->pages[req->index]; |
423 | ||
424 | req->pages[req->index] = NULL; | |
425 | SetPageUptodate(page); | |
426 | ||
427 | /* send the page to the cache */ | |
428 | #ifdef CONFIG_AFS_FSCACHE | |
429 | if (PageFsCache(page) && | |
ee1235a9 DH |
430 | fscache_write_page(vnode->cache, page, vnode->status.size, |
431 | GFP_KERNEL) != 0) { | |
91b467e0 DH |
432 | fscache_uncache_page(vnode->cache, page); |
433 | BUG_ON(PageFsCache(page)); | |
434 | } | |
435 | #endif | |
436 | unlock_page(page); | |
437 | put_page(page); | |
438 | } | |
439 | ||
440 | /* | |
441 | * Read a contiguous set of pages. | |
442 | */ | |
443 | static int afs_readpages_one(struct file *file, struct address_space *mapping, | |
444 | struct list_head *pages) | |
445 | { | |
446 | struct afs_vnode *vnode = AFS_FS_I(mapping->host); | |
447 | struct afs_read *req; | |
448 | struct list_head *p; | |
449 | struct page *first, *page; | |
215804a9 | 450 | struct key *key = afs_file_key(file); |
91b467e0 DH |
451 | pgoff_t index; |
452 | int ret, n, i; | |
453 | ||
454 | /* Count the number of contiguous pages at the front of the list. Note | |
455 | * that the list goes prev-wards rather than next-wards. | |
456 | */ | |
f86196ea | 457 | first = lru_to_page(pages); |
91b467e0 DH |
458 | index = first->index + 1; |
459 | n = 1; | |
460 | for (p = first->lru.prev; p != pages; p = p->prev) { | |
461 | page = list_entry(p, struct page, lru); | |
462 | if (page->index != index) | |
463 | break; | |
464 | index++; | |
465 | n++; | |
466 | } | |
467 | ||
468 | req = kzalloc(sizeof(struct afs_read) + sizeof(struct page *) * n, | |
469 | GFP_NOFS); | |
470 | if (!req) | |
471 | return -ENOMEM; | |
472 | ||
f3ddee8d | 473 | refcount_set(&req->usage, 1); |
a58823ac | 474 | req->vnode = vnode; |
91b467e0 DH |
475 | req->page_done = afs_readpages_page_done; |
476 | req->pos = first->index; | |
477 | req->pos <<= PAGE_SHIFT; | |
f3ddee8d | 478 | req->pages = req->array; |
91b467e0 DH |
479 | |
480 | /* Transfer the pages to the request. We add them in until one fails | |
481 | * to add to the LRU and then we stop (as that'll make a hole in the | |
482 | * contiguous run. | |
483 | * | |
484 | * Note that it's possible for the file size to change whilst we're | |
485 | * doing this, but we rely on the server returning less than we asked | |
486 | * for if the file shrank. We also rely on this to deal with a partial | |
487 | * page at the end of the file. | |
488 | */ | |
489 | do { | |
f86196ea | 490 | page = lru_to_page(pages); |
91b467e0 DH |
491 | list_del(&page->lru); |
492 | index = page->index; | |
493 | if (add_to_page_cache_lru(page, mapping, index, | |
494 | readahead_gfp_mask(mapping))) { | |
495 | #ifdef CONFIG_AFS_FSCACHE | |
496 | fscache_uncache_page(vnode->cache, page); | |
497 | #endif | |
498 | put_page(page); | |
499 | break; | |
500 | } | |
501 | ||
502 | req->pages[req->nr_pages++] = page; | |
503 | req->len += PAGE_SIZE; | |
504 | } while (req->nr_pages < n); | |
505 | ||
506 | if (req->nr_pages == 0) { | |
507 | kfree(req); | |
508 | return 0; | |
509 | } | |
510 | ||
d2ddc776 | 511 | ret = afs_fetch_data(vnode, key, req); |
91b467e0 DH |
512 | if (ret < 0) |
513 | goto error; | |
514 | ||
515 | task_io_account_read(PAGE_SIZE * req->nr_pages); | |
516 | afs_put_read(req); | |
517 | return 0; | |
518 | ||
519 | error: | |
520 | if (ret == -ENOENT) { | |
521 | _debug("got NOENT from server" | |
522 | " - marking file deleted and stale"); | |
523 | set_bit(AFS_VNODE_DELETED, &vnode->flags); | |
524 | ret = -ESTALE; | |
525 | } | |
526 | ||
527 | for (i = 0; i < req->nr_pages; i++) { | |
528 | page = req->pages[i]; | |
529 | if (page) { | |
530 | #ifdef CONFIG_AFS_FSCACHE | |
531 | fscache_uncache_page(vnode->cache, page); | |
532 | #endif | |
533 | SetPageError(page); | |
534 | unlock_page(page); | |
535 | } | |
536 | } | |
537 | ||
538 | afs_put_read(req); | |
539 | return ret; | |
540 | } | |
541 | ||
1da177e4 | 542 | /* |
9b3f26c9 | 543 | * read a set of pages |
1da177e4 | 544 | */ |
9b3f26c9 DH |
545 | static int afs_readpages(struct file *file, struct address_space *mapping, |
546 | struct list_head *pages, unsigned nr_pages) | |
1da177e4 | 547 | { |
215804a9 | 548 | struct key *key = afs_file_key(file); |
9b3f26c9 DH |
549 | struct afs_vnode *vnode; |
550 | int ret = 0; | |
1da177e4 | 551 | |
f6d335c0 AV |
552 | _enter("{%d},{%lu},,%d", |
553 | key_serial(key), mapping->host->i_ino, nr_pages); | |
554 | ||
555 | ASSERT(key != NULL); | |
1da177e4 | 556 | |
9b3f26c9 | 557 | vnode = AFS_FS_I(mapping->host); |
ad2a8e60 | 558 | if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) { |
9b3f26c9 DH |
559 | _leave(" = -ESTALE"); |
560 | return -ESTALE; | |
561 | } | |
1da177e4 | 562 | |
9b3f26c9 DH |
563 | /* attempt to read as many of the pages as possible */ |
564 | #ifdef CONFIG_AFS_FSCACHE | |
565 | ret = fscache_read_or_alloc_pages(vnode->cache, | |
566 | mapping, | |
567 | pages, | |
568 | &nr_pages, | |
569 | afs_file_readpage_read_complete, | |
570 | NULL, | |
571 | mapping_gfp_mask(mapping)); | |
572 | #else | |
573 | ret = -ENOBUFS; | |
574 | #endif | |
575 | ||
576 | switch (ret) { | |
577 | /* all pages are being read from the cache */ | |
578 | case 0: | |
579 | BUG_ON(!list_empty(pages)); | |
580 | BUG_ON(nr_pages != 0); | |
581 | _leave(" = 0 [reading all]"); | |
582 | return 0; | |
583 | ||
584 | /* there were pages that couldn't be read from the cache */ | |
585 | case -ENODATA: | |
586 | case -ENOBUFS: | |
587 | break; | |
588 | ||
589 | /* other error */ | |
590 | default: | |
591 | _leave(" = %d", ret); | |
592 | return ret; | |
1da177e4 LT |
593 | } |
594 | ||
91b467e0 DH |
595 | while (!list_empty(pages)) { |
596 | ret = afs_readpages_one(file, mapping, pages); | |
597 | if (ret < 0) | |
598 | break; | |
599 | } | |
9b3f26c9 DH |
600 | |
601 | _leave(" = %d [netting]", ret); | |
602 | return ret; | |
ec26815a | 603 | } |
1da177e4 | 604 | |
1da177e4 | 605 | /* |
9b3f26c9 DH |
606 | * invalidate part or all of a page |
607 | * - release a page and clean up its private data if offset is 0 (indicating | |
608 | * the entire page) | |
609 | */ | |
d47992f8 LC |
610 | static void afs_invalidatepage(struct page *page, unsigned int offset, |
611 | unsigned int length) | |
9b3f26c9 | 612 | { |
13524ab3 DH |
613 | struct afs_vnode *vnode = AFS_FS_I(page->mapping->host); |
614 | unsigned long priv; | |
615 | ||
d47992f8 | 616 | _enter("{%lu},%u,%u", page->index, offset, length); |
9b3f26c9 DH |
617 | |
618 | BUG_ON(!PageLocked(page)); | |
619 | ||
620 | /* we clean up only if the entire page is being invalidated */ | |
09cbfeaf | 621 | if (offset == 0 && length == PAGE_SIZE) { |
9b3f26c9 DH |
622 | #ifdef CONFIG_AFS_FSCACHE |
623 | if (PageFsCache(page)) { | |
624 | struct afs_vnode *vnode = AFS_FS_I(page->mapping->host); | |
625 | fscache_wait_on_page_write(vnode->cache, page); | |
626 | fscache_uncache_page(vnode->cache, page); | |
9b3f26c9 DH |
627 | } |
628 | #endif | |
629 | ||
630 | if (PagePrivate(page)) { | |
13524ab3 DH |
631 | priv = page_private(page); |
632 | trace_afs_page_dirty(vnode, tracepoint_string("inval"), | |
633 | page->index, priv); | |
4343d008 DH |
634 | set_page_private(page, 0); |
635 | ClearPagePrivate(page); | |
9b3f26c9 DH |
636 | } |
637 | } | |
638 | ||
639 | _leave(""); | |
640 | } | |
641 | ||
642 | /* | |
643 | * release a page and clean up its private state if it's not busy | |
644 | * - return true if the page can now be released, false if not | |
1da177e4 | 645 | */ |
416351f2 | 646 | static int afs_releasepage(struct page *page, gfp_t gfp_flags) |
1da177e4 | 647 | { |
416351f2 | 648 | struct afs_vnode *vnode = AFS_FS_I(page->mapping->host); |
13524ab3 | 649 | unsigned long priv; |
1da177e4 | 650 | |
3b6492df | 651 | _enter("{{%llx:%llu}[%lu],%lx},%x", |
416351f2 DH |
652 | vnode->fid.vid, vnode->fid.vnode, page->index, page->flags, |
653 | gfp_flags); | |
1da177e4 | 654 | |
9b3f26c9 DH |
655 | /* deny if page is being written to the cache and the caller hasn't |
656 | * elected to wait */ | |
657 | #ifdef CONFIG_AFS_FSCACHE | |
201a1542 DH |
658 | if (!fscache_maybe_release_page(vnode->cache, page, gfp_flags)) { |
659 | _leave(" = F [cache busy]"); | |
660 | return 0; | |
9b3f26c9 DH |
661 | } |
662 | #endif | |
663 | ||
1da177e4 | 664 | if (PagePrivate(page)) { |
13524ab3 DH |
665 | priv = page_private(page); |
666 | trace_afs_page_dirty(vnode, tracepoint_string("rel"), | |
667 | page->index, priv); | |
4343d008 | 668 | set_page_private(page, 0); |
1da177e4 | 669 | ClearPagePrivate(page); |
1da177e4 LT |
670 | } |
671 | ||
9b3f26c9 DH |
672 | /* indicate that the page can be released */ |
673 | _leave(" = T"); | |
674 | return 1; | |
ec26815a | 675 | } |
1cf7a151 DH |
676 | |
677 | /* | |
678 | * Handle setting up a memory mapping on an AFS file. | |
679 | */ | |
680 | static int afs_file_mmap(struct file *file, struct vm_area_struct *vma) | |
681 | { | |
682 | int ret; | |
683 | ||
684 | ret = generic_file_mmap(file, vma); | |
685 | if (ret == 0) | |
686 | vma->vm_ops = &afs_vm_ops; | |
687 | return ret; | |
688 | } |