Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/nfs/read.c | |
3 | * | |
4 | * Block I/O for NFS | |
5 | * | |
6 | * Partial copy of Linus' read cache modifications to fs/nfs/file.c | |
7 | * modified for async RPC by okir@monad.swb.de | |
1da177e4 LT |
8 | */ |
9 | ||
1da177e4 LT |
10 | #include <linux/time.h> |
11 | #include <linux/kernel.h> | |
12 | #include <linux/errno.h> | |
13 | #include <linux/fcntl.h> | |
14 | #include <linux/stat.h> | |
15 | #include <linux/mm.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/pagemap.h> | |
18 | #include <linux/sunrpc/clnt.h> | |
19 | #include <linux/nfs_fs.h> | |
20 | #include <linux/nfs_page.h> | |
21 | #include <linux/smp_lock.h> | |
22 | ||
23 | #include <asm/system.h> | |
24 | ||
49a70f27 | 25 | #include "internal.h" |
91d5b470 CL |
26 | #include "iostat.h" |
27 | ||
1da177e4 LT |
28 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE |
29 | ||
8d5658c9 TM |
30 | static int nfs_pagein_multi(struct inode *, struct list_head *, unsigned int, size_t, int); |
31 | static int nfs_pagein_one(struct inode *, struct list_head *, unsigned int, size_t, int); | |
ec06c096 TM |
32 | static const struct rpc_call_ops nfs_read_partial_ops; |
33 | static const struct rpc_call_ops nfs_read_full_ops; | |
1da177e4 | 34 | |
e18b890b | 35 | static struct kmem_cache *nfs_rdata_cachep; |
3feb2d49 | 36 | static mempool_t *nfs_rdata_mempool; |
1da177e4 LT |
37 | |
38 | #define MIN_POOL_READ (32) | |
39 | ||
8d5658c9 | 40 | struct nfs_read_data *nfs_readdata_alloc(unsigned int pagecount) |
3feb2d49 | 41 | { |
e6b4f8da | 42 | struct nfs_read_data *p = mempool_alloc(nfs_rdata_mempool, GFP_NOFS); |
3feb2d49 TM |
43 | |
44 | if (p) { | |
45 | memset(p, 0, sizeof(*p)); | |
46 | INIT_LIST_HEAD(&p->pages); | |
e9f7bee1 | 47 | p->npages = pagecount; |
0d0b5cb3 CL |
48 | if (pagecount <= ARRAY_SIZE(p->page_array)) |
49 | p->pagevec = p->page_array; | |
3feb2d49 | 50 | else { |
0d0b5cb3 CL |
51 | p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_NOFS); |
52 | if (!p->pagevec) { | |
3feb2d49 TM |
53 | mempool_free(p, nfs_rdata_mempool); |
54 | p = NULL; | |
55 | } | |
56 | } | |
57 | } | |
58 | return p; | |
59 | } | |
60 | ||
5e4424af | 61 | static void nfs_readdata_free(struct nfs_read_data *p) |
3feb2d49 TM |
62 | { |
63 | if (p && (p->pagevec != &p->page_array[0])) | |
64 | kfree(p->pagevec); | |
65 | mempool_free(p, nfs_rdata_mempool); | |
66 | } | |
67 | ||
963d8fe5 | 68 | void nfs_readdata_release(void *data) |
1da177e4 | 69 | { |
383ba719 TM |
70 | struct nfs_read_data *rdata = data; |
71 | ||
72 | put_nfs_open_context(rdata->args.context); | |
73 | nfs_readdata_free(rdata); | |
1da177e4 LT |
74 | } |
75 | ||
1da177e4 LT |
76 | static |
77 | int nfs_return_empty_page(struct page *page) | |
78 | { | |
eebd2aa3 | 79 | zero_user(page, 0, PAGE_CACHE_SIZE); |
1da177e4 LT |
80 | SetPageUptodate(page); |
81 | unlock_page(page); | |
82 | return 0; | |
83 | } | |
84 | ||
1de3fc12 TM |
85 | static void nfs_readpage_truncate_uninitialised_page(struct nfs_read_data *data) |
86 | { | |
87 | unsigned int remainder = data->args.count - data->res.count; | |
88 | unsigned int base = data->args.pgbase + data->res.count; | |
89 | unsigned int pglen; | |
90 | struct page **pages; | |
91 | ||
92 | if (data->res.eof == 0 || remainder == 0) | |
93 | return; | |
94 | /* | |
95 | * Note: "remainder" can never be negative, since we check for | |
96 | * this in the XDR code. | |
97 | */ | |
98 | pages = &data->args.pages[base >> PAGE_CACHE_SHIFT]; | |
99 | base &= ~PAGE_CACHE_MASK; | |
100 | pglen = PAGE_CACHE_SIZE - base; | |
79558f36 TM |
101 | for (;;) { |
102 | if (remainder <= pglen) { | |
eebd2aa3 | 103 | zero_user(*pages, base, remainder); |
79558f36 TM |
104 | break; |
105 | } | |
eebd2aa3 | 106 | zero_user(*pages, base, pglen); |
79558f36 TM |
107 | pages++; |
108 | remainder -= pglen; | |
109 | pglen = PAGE_CACHE_SIZE; | |
110 | base = 0; | |
111 | } | |
1de3fc12 TM |
112 | } |
113 | ||
1da177e4 LT |
114 | static int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode, |
115 | struct page *page) | |
116 | { | |
117 | LIST_HEAD(one_request); | |
118 | struct nfs_page *new; | |
119 | unsigned int len; | |
120 | ||
49a70f27 | 121 | len = nfs_page_length(page); |
1da177e4 LT |
122 | if (len == 0) |
123 | return nfs_return_empty_page(page); | |
124 | new = nfs_create_request(ctx, inode, page, 0, len); | |
125 | if (IS_ERR(new)) { | |
126 | unlock_page(page); | |
127 | return PTR_ERR(new); | |
128 | } | |
129 | if (len < PAGE_CACHE_SIZE) | |
eebd2aa3 | 130 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
1da177e4 | 131 | |
1da177e4 | 132 | nfs_list_add_request(new, &one_request); |
bcb71bba | 133 | if (NFS_SERVER(inode)->rsize < PAGE_CACHE_SIZE) |
8d5658c9 | 134 | nfs_pagein_multi(inode, &one_request, 1, len, 0); |
bcb71bba | 135 | else |
8d5658c9 | 136 | nfs_pagein_one(inode, &one_request, 1, len, 0); |
1da177e4 LT |
137 | return 0; |
138 | } | |
139 | ||
140 | static void nfs_readpage_release(struct nfs_page *req) | |
141 | { | |
142 | unlock_page(req->wb_page); | |
143 | ||
1da177e4 | 144 | dprintk("NFS: read done (%s/%Ld %d@%Ld)\n", |
88be9f99 TM |
145 | req->wb_context->path.dentry->d_inode->i_sb->s_id, |
146 | (long long)NFS_FILEID(req->wb_context->path.dentry->d_inode), | |
1da177e4 LT |
147 | req->wb_bytes, |
148 | (long long)req_offset(req)); | |
10d2c46f NW |
149 | nfs_clear_request(req); |
150 | nfs_release_request(req); | |
1da177e4 LT |
151 | } |
152 | ||
153 | /* | |
154 | * Set up the NFS read request struct | |
155 | */ | |
156 | static void nfs_read_rpcsetup(struct nfs_page *req, struct nfs_read_data *data, | |
ec06c096 | 157 | const struct rpc_call_ops *call_ops, |
1da177e4 LT |
158 | unsigned int count, unsigned int offset) |
159 | { | |
84115e1c TM |
160 | struct inode *inode = req->wb_context->path.dentry->d_inode; |
161 | int swap_flags = IS_SWAPFILE(inode) ? NFS_RPC_SWAPFLAGS : 0; | |
07737691 | 162 | struct rpc_task *task; |
bdc7f021 TM |
163 | struct rpc_message msg = { |
164 | .rpc_argp = &data->args, | |
165 | .rpc_resp = &data->res, | |
166 | .rpc_cred = req->wb_context->cred, | |
167 | }; | |
84115e1c | 168 | struct rpc_task_setup task_setup_data = { |
07737691 | 169 | .task = &data->task, |
84115e1c | 170 | .rpc_client = NFS_CLIENT(inode), |
bdc7f021 | 171 | .rpc_message = &msg, |
84115e1c TM |
172 | .callback_ops = call_ops, |
173 | .callback_data = data, | |
101070ca | 174 | .workqueue = nfsiod_workqueue, |
84115e1c TM |
175 | .flags = RPC_TASK_ASYNC | swap_flags, |
176 | }; | |
1da177e4 LT |
177 | |
178 | data->req = req; | |
84115e1c | 179 | data->inode = inode; |
bdc7f021 | 180 | data->cred = msg.rpc_cred; |
1da177e4 LT |
181 | |
182 | data->args.fh = NFS_FH(inode); | |
183 | data->args.offset = req_offset(req) + offset; | |
184 | data->args.pgbase = req->wb_pgbase + offset; | |
185 | data->args.pages = data->pagevec; | |
186 | data->args.count = count; | |
383ba719 | 187 | data->args.context = get_nfs_open_context(req->wb_context); |
1da177e4 LT |
188 | |
189 | data->res.fattr = &data->fattr; | |
190 | data->res.count = count; | |
191 | data->res.eof = 0; | |
0e574af1 | 192 | nfs_fattr_init(&data->fattr); |
1da177e4 | 193 | |
ec06c096 | 194 | /* Set up the initial task struct. */ |
bdc7f021 | 195 | NFS_PROTO(inode)->read_setup(data, &msg); |
1da177e4 | 196 | |
a3f565b1 | 197 | dprintk("NFS: %5u initiated read call (req %s/%Ld, %u bytes @ offset %Lu)\n", |
1da177e4 LT |
198 | data->task.tk_pid, |
199 | inode->i_sb->s_id, | |
200 | (long long)NFS_FILEID(inode), | |
201 | count, | |
202 | (unsigned long long)data->args.offset); | |
bdc7f021 | 203 | |
07737691 TM |
204 | task = rpc_run_task(&task_setup_data); |
205 | if (!IS_ERR(task)) | |
206 | rpc_put_task(task); | |
1da177e4 LT |
207 | } |
208 | ||
209 | static void | |
210 | nfs_async_read_error(struct list_head *head) | |
211 | { | |
212 | struct nfs_page *req; | |
213 | ||
214 | while (!list_empty(head)) { | |
215 | req = nfs_list_entry(head->next); | |
216 | nfs_list_remove_request(req); | |
217 | SetPageError(req->wb_page); | |
218 | nfs_readpage_release(req); | |
219 | } | |
220 | } | |
221 | ||
1da177e4 LT |
222 | /* |
223 | * Generate multiple requests to fill a single page. | |
224 | * | |
225 | * We optimize to reduce the number of read operations on the wire. If we | |
226 | * detect that we're reading a page, or an area of a page, that is past the | |
227 | * end of file, we do not generate NFS read operations but just clear the | |
228 | * parts of the page that would have come back zero from the server anyway. | |
229 | * | |
230 | * We rely on the cached value of i_size to make this determination; another | |
231 | * client can fill pages on the server past our cached end-of-file, but we | |
232 | * won't see the new data until our attribute cache is updated. This is more | |
233 | * or less conventional NFS client behavior. | |
234 | */ | |
8d5658c9 | 235 | static int nfs_pagein_multi(struct inode *inode, struct list_head *head, unsigned int npages, size_t count, int flags) |
1da177e4 LT |
236 | { |
237 | struct nfs_page *req = nfs_list_entry(head->next); | |
238 | struct page *page = req->wb_page; | |
239 | struct nfs_read_data *data; | |
e9f7bee1 TM |
240 | size_t rsize = NFS_SERVER(inode)->rsize, nbytes; |
241 | unsigned int offset; | |
1da177e4 LT |
242 | int requests = 0; |
243 | LIST_HEAD(list); | |
244 | ||
245 | nfs_list_remove_request(req); | |
246 | ||
bcb71bba | 247 | nbytes = count; |
e9f7bee1 TM |
248 | do { |
249 | size_t len = min(nbytes,rsize); | |
250 | ||
8d5658c9 | 251 | data = nfs_readdata_alloc(1); |
1da177e4 LT |
252 | if (!data) |
253 | goto out_bad; | |
254 | INIT_LIST_HEAD(&data->pages); | |
255 | list_add(&data->pages, &list); | |
256 | requests++; | |
e9f7bee1 TM |
257 | nbytes -= len; |
258 | } while(nbytes != 0); | |
1da177e4 LT |
259 | atomic_set(&req->wb_complete, requests); |
260 | ||
261 | ClearPageError(page); | |
262 | offset = 0; | |
bcb71bba | 263 | nbytes = count; |
1da177e4 LT |
264 | do { |
265 | data = list_entry(list.next, struct nfs_read_data, pages); | |
266 | list_del_init(&data->pages); | |
267 | ||
268 | data->pagevec[0] = page; | |
1da177e4 | 269 | |
bcb71bba TM |
270 | if (nbytes < rsize) |
271 | rsize = nbytes; | |
272 | nfs_read_rpcsetup(req, data, &nfs_read_partial_ops, | |
273 | rsize, offset); | |
274 | offset += rsize; | |
275 | nbytes -= rsize; | |
1da177e4 LT |
276 | } while (nbytes != 0); |
277 | ||
278 | return 0; | |
279 | ||
280 | out_bad: | |
281 | while (!list_empty(&list)) { | |
282 | data = list_entry(list.next, struct nfs_read_data, pages); | |
283 | list_del(&data->pages); | |
284 | nfs_readdata_free(data); | |
285 | } | |
286 | SetPageError(page); | |
287 | nfs_readpage_release(req); | |
288 | return -ENOMEM; | |
289 | } | |
290 | ||
8d5658c9 | 291 | static int nfs_pagein_one(struct inode *inode, struct list_head *head, unsigned int npages, size_t count, int flags) |
1da177e4 LT |
292 | { |
293 | struct nfs_page *req; | |
294 | struct page **pages; | |
295 | struct nfs_read_data *data; | |
1da177e4 | 296 | |
8d5658c9 | 297 | data = nfs_readdata_alloc(npages); |
1da177e4 LT |
298 | if (!data) |
299 | goto out_bad; | |
300 | ||
301 | INIT_LIST_HEAD(&data->pages); | |
302 | pages = data->pagevec; | |
1da177e4 LT |
303 | while (!list_empty(head)) { |
304 | req = nfs_list_entry(head->next); | |
305 | nfs_list_remove_request(req); | |
306 | nfs_list_add_request(req, &data->pages); | |
307 | ClearPageError(req->wb_page); | |
308 | *pages++ = req->wb_page; | |
1da177e4 LT |
309 | } |
310 | req = nfs_list_entry(data->pages.next); | |
311 | ||
ec06c096 | 312 | nfs_read_rpcsetup(req, data, &nfs_read_full_ops, count, 0); |
1da177e4 LT |
313 | return 0; |
314 | out_bad: | |
315 | nfs_async_read_error(head); | |
316 | return -ENOMEM; | |
317 | } | |
318 | ||
0b671301 TM |
319 | /* |
320 | * This is the callback from RPC telling us whether a reply was | |
321 | * received or some error occurred (timeout or socket shutdown). | |
322 | */ | |
323 | int nfs_readpage_result(struct rpc_task *task, struct nfs_read_data *data) | |
324 | { | |
325 | int status; | |
326 | ||
a3f565b1 | 327 | dprintk("NFS: %s: %5u, (status %d)\n", __FUNCTION__, task->tk_pid, |
0b671301 TM |
328 | task->tk_status); |
329 | ||
330 | status = NFS_PROTO(data->inode)->read_done(task, data); | |
331 | if (status != 0) | |
332 | return status; | |
333 | ||
334 | nfs_add_stats(data->inode, NFSIOS_SERVERREADBYTES, data->res.count); | |
335 | ||
336 | if (task->tk_status == -ESTALE) { | |
3a10c30a | 337 | set_bit(NFS_INO_STALE, &NFS_I(data->inode)->flags); |
0b671301 TM |
338 | nfs_mark_for_revalidate(data->inode); |
339 | } | |
0b671301 TM |
340 | return 0; |
341 | } | |
342 | ||
343 | static int nfs_readpage_retry(struct rpc_task *task, struct nfs_read_data *data) | |
344 | { | |
345 | struct nfs_readargs *argp = &data->args; | |
346 | struct nfs_readres *resp = &data->res; | |
347 | ||
348 | if (resp->eof || resp->count == argp->count) | |
349 | return 0; | |
350 | ||
351 | /* This is a short read! */ | |
352 | nfs_inc_stats(data->inode, NFSIOS_SHORTREAD); | |
353 | /* Has the server at least made some progress? */ | |
354 | if (resp->count == 0) | |
355 | return 0; | |
356 | ||
357 | /* Yes, so retry the read at the end of the data */ | |
358 | argp->offset += resp->count; | |
359 | argp->pgbase += resp->count; | |
360 | argp->count -= resp->count; | |
361 | rpc_restart_call(task); | |
362 | return -EAGAIN; | |
363 | } | |
364 | ||
1da177e4 LT |
365 | /* |
366 | * Handle a read reply that fills part of a page. | |
367 | */ | |
ec06c096 | 368 | static void nfs_readpage_result_partial(struct rpc_task *task, void *calldata) |
1da177e4 | 369 | { |
ec06c096 | 370 | struct nfs_read_data *data = calldata; |
1da177e4 LT |
371 | struct nfs_page *req = data->req; |
372 | struct page *page = req->wb_page; | |
373 | ||
ec06c096 TM |
374 | if (nfs_readpage_result(task, data) != 0) |
375 | return; | |
0b671301 TM |
376 | |
377 | if (likely(task->tk_status >= 0)) { | |
378 | nfs_readpage_truncate_uninitialised_page(data); | |
379 | if (nfs_readpage_retry(task, data) != 0) | |
380 | return; | |
381 | } | |
382 | if (unlikely(task->tk_status < 0)) | |
383 | SetPageError(page); | |
1da177e4 LT |
384 | if (atomic_dec_and_test(&req->wb_complete)) { |
385 | if (!PageError(page)) | |
386 | SetPageUptodate(page); | |
387 | nfs_readpage_release(req); | |
388 | } | |
389 | } | |
390 | ||
ec06c096 TM |
391 | static const struct rpc_call_ops nfs_read_partial_ops = { |
392 | .rpc_call_done = nfs_readpage_result_partial, | |
393 | .rpc_release = nfs_readdata_release, | |
394 | }; | |
395 | ||
1de3fc12 TM |
396 | static void nfs_readpage_set_pages_uptodate(struct nfs_read_data *data) |
397 | { | |
398 | unsigned int count = data->res.count; | |
399 | unsigned int base = data->args.pgbase; | |
400 | struct page **pages; | |
401 | ||
79558f36 TM |
402 | if (data->res.eof) |
403 | count = data->args.count; | |
1de3fc12 TM |
404 | if (unlikely(count == 0)) |
405 | return; | |
406 | pages = &data->args.pages[base >> PAGE_CACHE_SHIFT]; | |
407 | base &= ~PAGE_CACHE_MASK; | |
408 | count += base; | |
409 | for (;count >= PAGE_CACHE_SIZE; count -= PAGE_CACHE_SIZE, pages++) | |
410 | SetPageUptodate(*pages); | |
0b671301 TM |
411 | if (count == 0) |
412 | return; | |
413 | /* Was this a short read? */ | |
414 | if (data->res.eof || data->res.count == data->args.count) | |
1de3fc12 TM |
415 | SetPageUptodate(*pages); |
416 | } | |
417 | ||
1da177e4 LT |
418 | /* |
419 | * This is the callback from RPC telling us whether a reply was | |
420 | * received or some error occurred (timeout or socket shutdown). | |
421 | */ | |
ec06c096 | 422 | static void nfs_readpage_result_full(struct rpc_task *task, void *calldata) |
1da177e4 | 423 | { |
ec06c096 | 424 | struct nfs_read_data *data = calldata; |
1da177e4 | 425 | |
0b671301 TM |
426 | if (nfs_readpage_result(task, data) != 0) |
427 | return; | |
1de3fc12 | 428 | /* |
0b671301 | 429 | * Note: nfs_readpage_retry may change the values of |
1de3fc12 | 430 | * data->args. In the multi-page case, we therefore need |
0b671301 TM |
431 | * to ensure that we call nfs_readpage_set_pages_uptodate() |
432 | * first. | |
1de3fc12 TM |
433 | */ |
434 | if (likely(task->tk_status >= 0)) { | |
435 | nfs_readpage_truncate_uninitialised_page(data); | |
436 | nfs_readpage_set_pages_uptodate(data); | |
0b671301 TM |
437 | if (nfs_readpage_retry(task, data) != 0) |
438 | return; | |
439 | } | |
1da177e4 LT |
440 | while (!list_empty(&data->pages)) { |
441 | struct nfs_page *req = nfs_list_entry(data->pages.next); | |
1da177e4 | 442 | |
1de3fc12 | 443 | nfs_list_remove_request(req); |
1da177e4 LT |
444 | nfs_readpage_release(req); |
445 | } | |
446 | } | |
447 | ||
ec06c096 TM |
448 | static const struct rpc_call_ops nfs_read_full_ops = { |
449 | .rpc_call_done = nfs_readpage_result_full, | |
450 | .rpc_release = nfs_readdata_release, | |
451 | }; | |
452 | ||
1da177e4 LT |
453 | /* |
454 | * Read a page over NFS. | |
455 | * We read the page synchronously in the following case: | |
456 | * - The error flag is set for this page. This happens only when a | |
457 | * previous async read operation failed. | |
458 | */ | |
459 | int nfs_readpage(struct file *file, struct page *page) | |
460 | { | |
461 | struct nfs_open_context *ctx; | |
462 | struct inode *inode = page->mapping->host; | |
463 | int error; | |
464 | ||
465 | dprintk("NFS: nfs_readpage (%p %ld@%lu)\n", | |
466 | page, PAGE_CACHE_SIZE, page->index); | |
91d5b470 CL |
467 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGE); |
468 | nfs_add_stats(inode, NFSIOS_READPAGES, 1); | |
469 | ||
1da177e4 LT |
470 | /* |
471 | * Try to flush any pending writes to the file.. | |
472 | * | |
473 | * NOTE! Because we own the page lock, there cannot | |
474 | * be any new pending writes generated at this point | |
475 | * for this page (other pages can be written to). | |
476 | */ | |
477 | error = nfs_wb_page(inode, page); | |
478 | if (error) | |
de05a0cc TM |
479 | goto out_unlock; |
480 | if (PageUptodate(page)) | |
481 | goto out_unlock; | |
1da177e4 | 482 | |
5f004cf2 TM |
483 | error = -ESTALE; |
484 | if (NFS_STALE(inode)) | |
de05a0cc | 485 | goto out_unlock; |
5f004cf2 | 486 | |
1da177e4 | 487 | if (file == NULL) { |
cf1308ff | 488 | error = -EBADF; |
d530838b | 489 | ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
1da177e4 | 490 | if (ctx == NULL) |
de05a0cc | 491 | goto out_unlock; |
1da177e4 | 492 | } else |
cd3758e3 | 493 | ctx = get_nfs_open_context(nfs_file_open_context(file)); |
1da177e4 | 494 | |
8e0969f0 TM |
495 | error = nfs_readpage_async(ctx, inode, page); |
496 | ||
1da177e4 LT |
497 | put_nfs_open_context(ctx); |
498 | return error; | |
de05a0cc | 499 | out_unlock: |
1da177e4 LT |
500 | unlock_page(page); |
501 | return error; | |
502 | } | |
503 | ||
504 | struct nfs_readdesc { | |
8b09bee3 | 505 | struct nfs_pageio_descriptor *pgio; |
1da177e4 LT |
506 | struct nfs_open_context *ctx; |
507 | }; | |
508 | ||
509 | static int | |
510 | readpage_async_filler(void *data, struct page *page) | |
511 | { | |
512 | struct nfs_readdesc *desc = (struct nfs_readdesc *)data; | |
513 | struct inode *inode = page->mapping->host; | |
514 | struct nfs_page *new; | |
515 | unsigned int len; | |
de05a0cc TM |
516 | int error; |
517 | ||
518 | error = nfs_wb_page(inode, page); | |
519 | if (error) | |
520 | goto out_unlock; | |
521 | if (PageUptodate(page)) | |
522 | goto out_unlock; | |
1da177e4 | 523 | |
49a70f27 | 524 | len = nfs_page_length(page); |
1da177e4 LT |
525 | if (len == 0) |
526 | return nfs_return_empty_page(page); | |
de05a0cc | 527 | |
1da177e4 | 528 | new = nfs_create_request(desc->ctx, inode, page, 0, len); |
de05a0cc TM |
529 | if (IS_ERR(new)) |
530 | goto out_error; | |
531 | ||
1da177e4 | 532 | if (len < PAGE_CACHE_SIZE) |
eebd2aa3 | 533 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
8b09bee3 | 534 | nfs_pageio_add_request(desc->pgio, new); |
1da177e4 | 535 | return 0; |
de05a0cc TM |
536 | out_error: |
537 | error = PTR_ERR(new); | |
538 | SetPageError(page); | |
539 | out_unlock: | |
540 | unlock_page(page); | |
541 | return error; | |
1da177e4 LT |
542 | } |
543 | ||
544 | int nfs_readpages(struct file *filp, struct address_space *mapping, | |
545 | struct list_head *pages, unsigned nr_pages) | |
546 | { | |
8b09bee3 | 547 | struct nfs_pageio_descriptor pgio; |
1da177e4 | 548 | struct nfs_readdesc desc = { |
8b09bee3 | 549 | .pgio = &pgio, |
1da177e4 LT |
550 | }; |
551 | struct inode *inode = mapping->host; | |
552 | struct nfs_server *server = NFS_SERVER(inode); | |
8b09bee3 TM |
553 | size_t rsize = server->rsize; |
554 | unsigned long npages; | |
5f004cf2 | 555 | int ret = -ESTALE; |
1da177e4 LT |
556 | |
557 | dprintk("NFS: nfs_readpages (%s/%Ld %d)\n", | |
558 | inode->i_sb->s_id, | |
559 | (long long)NFS_FILEID(inode), | |
560 | nr_pages); | |
91d5b470 | 561 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGES); |
1da177e4 | 562 | |
5f004cf2 TM |
563 | if (NFS_STALE(inode)) |
564 | goto out; | |
565 | ||
1da177e4 | 566 | if (filp == NULL) { |
d530838b | 567 | desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
1da177e4 LT |
568 | if (desc.ctx == NULL) |
569 | return -EBADF; | |
570 | } else | |
cd3758e3 | 571 | desc.ctx = get_nfs_open_context(nfs_file_open_context(filp)); |
8b09bee3 TM |
572 | if (rsize < PAGE_CACHE_SIZE) |
573 | nfs_pageio_init(&pgio, inode, nfs_pagein_multi, rsize, 0); | |
574 | else | |
575 | nfs_pageio_init(&pgio, inode, nfs_pagein_one, rsize, 0); | |
576 | ||
1da177e4 | 577 | ret = read_cache_pages(mapping, pages, readpage_async_filler, &desc); |
8b09bee3 TM |
578 | |
579 | nfs_pageio_complete(&pgio); | |
580 | npages = (pgio.pg_bytes_written + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; | |
581 | nfs_add_stats(inode, NFSIOS_READPAGES, npages); | |
1da177e4 | 582 | put_nfs_open_context(desc.ctx); |
5f004cf2 | 583 | out: |
1da177e4 LT |
584 | return ret; |
585 | } | |
586 | ||
f7b422b1 | 587 | int __init nfs_init_readpagecache(void) |
1da177e4 LT |
588 | { |
589 | nfs_rdata_cachep = kmem_cache_create("nfs_read_data", | |
590 | sizeof(struct nfs_read_data), | |
591 | 0, SLAB_HWCACHE_ALIGN, | |
20c2df83 | 592 | NULL); |
1da177e4 LT |
593 | if (nfs_rdata_cachep == NULL) |
594 | return -ENOMEM; | |
595 | ||
93d2341c MD |
596 | nfs_rdata_mempool = mempool_create_slab_pool(MIN_POOL_READ, |
597 | nfs_rdata_cachep); | |
1da177e4 LT |
598 | if (nfs_rdata_mempool == NULL) |
599 | return -ENOMEM; | |
600 | ||
601 | return 0; | |
602 | } | |
603 | ||
266bee88 | 604 | void nfs_destroy_readpagecache(void) |
1da177e4 LT |
605 | { |
606 | mempool_destroy(nfs_rdata_mempool); | |
1a1d92c1 | 607 | kmem_cache_destroy(nfs_rdata_cachep); |
1da177e4 | 608 | } |