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Commit | Line | Data |
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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> | |
64419a9b | 21 | #include <linux/module.h> |
1da177e4 | 22 | |
f11c88af | 23 | #include "nfs4_fs.h" |
49a70f27 | 24 | #include "internal.h" |
91d5b470 | 25 | #include "iostat.h" |
9a9fc1c0 | 26 | #include "fscache.h" |
fab5fc25 | 27 | #include "pnfs.h" |
91d5b470 | 28 | |
1da177e4 LT |
29 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE |
30 | ||
1751c363 | 31 | static const struct nfs_pageio_ops nfs_pageio_read_ops; |
4db6e0b7 | 32 | static const struct rpc_call_ops nfs_read_common_ops; |
061ae2ed | 33 | static const struct nfs_pgio_completion_ops nfs_async_read_completion_ops; |
1da177e4 | 34 | |
e18b890b | 35 | static struct kmem_cache *nfs_rdata_cachep; |
1da177e4 | 36 | |
c0752cdf | 37 | struct nfs_rw_header *nfs_readhdr_alloc(void) |
3feb2d49 | 38 | { |
c0752cdf | 39 | struct nfs_rw_header *rhdr; |
3feb2d49 | 40 | |
4db6e0b7 FI |
41 | rhdr = kmem_cache_zalloc(nfs_rdata_cachep, GFP_KERNEL); |
42 | if (rhdr) { | |
43 | struct nfs_pgio_header *hdr = &rhdr->header; | |
cd841605 FI |
44 | |
45 | INIT_LIST_HEAD(&hdr->pages); | |
4db6e0b7 FI |
46 | INIT_LIST_HEAD(&hdr->rpc_list); |
47 | spin_lock_init(&hdr->lock); | |
48 | atomic_set(&hdr->refcnt, 0); | |
49 | } | |
50 | return rhdr; | |
51 | } | |
89d77c8f | 52 | EXPORT_SYMBOL_GPL(nfs_readhdr_alloc); |
4db6e0b7 | 53 | |
cd841605 | 54 | void nfs_readhdr_free(struct nfs_pgio_header *hdr) |
3feb2d49 | 55 | { |
c0752cdf | 56 | struct nfs_rw_header *rhdr = container_of(hdr, struct nfs_rw_header, header); |
cd841605 FI |
57 | |
58 | kmem_cache_free(nfs_rdata_cachep, rhdr); | |
3feb2d49 | 59 | } |
89d77c8f | 60 | EXPORT_SYMBOL_GPL(nfs_readhdr_free); |
3feb2d49 | 61 | |
1da177e4 LT |
62 | static |
63 | int nfs_return_empty_page(struct page *page) | |
64 | { | |
eebd2aa3 | 65 | zero_user(page, 0, PAGE_CACHE_SIZE); |
1da177e4 LT |
66 | SetPageUptodate(page); |
67 | unlock_page(page); | |
68 | return 0; | |
69 | } | |
70 | ||
1abb5088 | 71 | void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, |
fab5fc25 | 72 | struct inode *inode, bool force_mds, |
061ae2ed | 73 | const struct nfs_pgio_completion_ops *compl_ops) |
1751c363 | 74 | { |
fab5fc25 CH |
75 | struct nfs_server *server = NFS_SERVER(inode); |
76 | const struct nfs_pageio_ops *pg_ops = &nfs_pageio_read_ops; | |
77 | ||
78 | #ifdef CONFIG_NFS_V4_1 | |
79 | if (server->pnfs_curr_ld && !force_mds) | |
80 | pg_ops = server->pnfs_curr_ld->pg_read_ops; | |
81 | #endif | |
82 | nfs_pageio_init(pgio, inode, pg_ops, compl_ops, server->rsize, 0); | |
1751c363 | 83 | } |
ddda8e0a | 84 | EXPORT_SYMBOL_GPL(nfs_pageio_init_read); |
1751c363 | 85 | |
493292dd TM |
86 | void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio) |
87 | { | |
88 | pgio->pg_ops = &nfs_pageio_read_ops; | |
89 | pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->rsize; | |
90 | } | |
1f945357 | 91 | EXPORT_SYMBOL_GPL(nfs_pageio_reset_read_mds); |
493292dd | 92 | |
f42b293d DH |
93 | int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode, |
94 | struct page *page) | |
1da177e4 | 95 | { |
1da177e4 LT |
96 | struct nfs_page *new; |
97 | unsigned int len; | |
c76069bd | 98 | struct nfs_pageio_descriptor pgio; |
1da177e4 | 99 | |
49a70f27 | 100 | len = nfs_page_length(page); |
1da177e4 LT |
101 | if (len == 0) |
102 | return nfs_return_empty_page(page); | |
103 | new = nfs_create_request(ctx, inode, page, 0, len); | |
104 | if (IS_ERR(new)) { | |
105 | unlock_page(page); | |
106 | return PTR_ERR(new); | |
107 | } | |
108 | if (len < PAGE_CACHE_SIZE) | |
eebd2aa3 | 109 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
1da177e4 | 110 | |
fab5fc25 CH |
111 | nfs_pageio_init_read(&pgio, inode, false, |
112 | &nfs_async_read_completion_ops); | |
d8007d4d | 113 | nfs_pageio_add_request(&pgio, new); |
1751c363 | 114 | nfs_pageio_complete(&pgio); |
2701d086 | 115 | NFS_I(inode)->read_io += pgio.pg_bytes_written; |
1da177e4 LT |
116 | return 0; |
117 | } | |
118 | ||
119 | static void nfs_readpage_release(struct nfs_page *req) | |
120 | { | |
3d4ff43d | 121 | struct inode *d_inode = req->wb_context->dentry->d_inode; |
7f8e05f6 DH |
122 | |
123 | if (PageUptodate(req->wb_page)) | |
124 | nfs_readpage_to_fscache(d_inode, req->wb_page, 0); | |
125 | ||
1da177e4 LT |
126 | unlock_page(req->wb_page); |
127 | ||
1e8968c5 | 128 | dprintk("NFS: read done (%s/%Lu %d@%Ld)\n", |
3d4ff43d | 129 | req->wb_context->dentry->d_inode->i_sb->s_id, |
1e8968c5 | 130 | (unsigned long long)NFS_FILEID(req->wb_context->dentry->d_inode), |
1da177e4 LT |
131 | req->wb_bytes, |
132 | (long long)req_offset(req)); | |
10d2c46f | 133 | nfs_release_request(req); |
1da177e4 LT |
134 | } |
135 | ||
4db6e0b7 | 136 | /* Note io was page aligned */ |
061ae2ed | 137 | static void nfs_read_completion(struct nfs_pgio_header *hdr) |
4db6e0b7 FI |
138 | { |
139 | unsigned long bytes = 0; | |
140 | ||
141 | if (test_bit(NFS_IOHDR_REDO, &hdr->flags)) | |
142 | goto out; | |
4bd8b010 TM |
143 | while (!list_empty(&hdr->pages)) { |
144 | struct nfs_page *req = nfs_list_entry(hdr->pages.next); | |
145 | struct page *page = req->wb_page; | |
146 | ||
147 | if (test_bit(NFS_IOHDR_EOF, &hdr->flags)) { | |
148 | if (bytes > hdr->good_bytes) | |
149 | zero_user(page, 0, PAGE_SIZE); | |
150 | else if (hdr->good_bytes - bytes < PAGE_SIZE) | |
151 | zero_user_segment(page, | |
152 | hdr->good_bytes & ~PAGE_MASK, | |
153 | PAGE_SIZE); | |
4db6e0b7 | 154 | } |
4bd8b010 TM |
155 | bytes += req->wb_bytes; |
156 | if (test_bit(NFS_IOHDR_ERROR, &hdr->flags)) { | |
4db6e0b7 | 157 | if (bytes <= hdr->good_bytes) |
4bd8b010 TM |
158 | SetPageUptodate(page); |
159 | } else | |
160 | SetPageUptodate(page); | |
161 | nfs_list_remove_request(req); | |
162 | nfs_readpage_release(req); | |
4db6e0b7 FI |
163 | } |
164 | out: | |
165 | hdr->release(hdr); | |
166 | } | |
167 | ||
c5996c4e | 168 | int nfs_initiate_read(struct rpc_clnt *clnt, |
9c7e1b3d | 169 | struct nfs_pgio_data *data, |
9f0ec176 | 170 | const struct rpc_call_ops *call_ops, int flags) |
1da177e4 | 171 | { |
cd841605 | 172 | struct inode *inode = data->header->inode; |
84115e1c | 173 | int swap_flags = IS_SWAPFILE(inode) ? NFS_RPC_SWAPFLAGS : 0; |
07737691 | 174 | struct rpc_task *task; |
bdc7f021 TM |
175 | struct rpc_message msg = { |
176 | .rpc_argp = &data->args, | |
177 | .rpc_resp = &data->res, | |
cd841605 | 178 | .rpc_cred = data->header->cred, |
bdc7f021 | 179 | }; |
84115e1c | 180 | struct rpc_task_setup task_setup_data = { |
07737691 | 181 | .task = &data->task, |
64419a9b | 182 | .rpc_client = clnt, |
bdc7f021 | 183 | .rpc_message = &msg, |
84115e1c TM |
184 | .callback_ops = call_ops, |
185 | .callback_data = data, | |
101070ca | 186 | .workqueue = nfsiod_workqueue, |
9f0ec176 | 187 | .flags = RPC_TASK_ASYNC | swap_flags | flags, |
84115e1c | 188 | }; |
1da177e4 | 189 | |
64419a9b AA |
190 | /* Set up the initial task struct. */ |
191 | NFS_PROTO(inode)->read_setup(data, &msg); | |
192 | ||
1e8968c5 | 193 | dprintk("NFS: %5u initiated read call (req %s/%llu, %u bytes @ " |
64419a9b AA |
194 | "offset %llu)\n", |
195 | data->task.tk_pid, | |
196 | inode->i_sb->s_id, | |
1e8968c5 | 197 | (unsigned long long)NFS_FILEID(inode), |
64419a9b AA |
198 | data->args.count, |
199 | (unsigned long long)data->args.offset); | |
200 | ||
201 | task = rpc_run_task(&task_setup_data); | |
202 | if (IS_ERR(task)) | |
203 | return PTR_ERR(task); | |
204 | rpc_put_task(task); | |
205 | return 0; | |
206 | } | |
dc70d7b3 | 207 | EXPORT_SYMBOL_GPL(nfs_initiate_read); |
64419a9b AA |
208 | |
209 | /* | |
210 | * Set up the NFS read request struct | |
211 | */ | |
9c7e1b3d | 212 | static void nfs_read_rpcsetup(struct nfs_pgio_data *data, |
6e4efd56 | 213 | unsigned int count, unsigned int offset) |
64419a9b | 214 | { |
4db6e0b7 | 215 | struct nfs_page *req = data->header->req; |
1da177e4 | 216 | |
4db6e0b7 | 217 | data->args.fh = NFS_FH(data->header->inode); |
1da177e4 LT |
218 | data->args.offset = req_offset(req) + offset; |
219 | data->args.pgbase = req->wb_pgbase + offset; | |
30dd374f | 220 | data->args.pages = data->pages.pagevec; |
1da177e4 | 221 | data->args.count = count; |
383ba719 | 222 | data->args.context = get_nfs_open_context(req->wb_context); |
f11ac8db | 223 | data->args.lock_context = req->wb_lock_context; |
1da177e4 LT |
224 | |
225 | data->res.fattr = &data->fattr; | |
226 | data->res.count = count; | |
227 | data->res.eof = 0; | |
0e574af1 | 228 | nfs_fattr_init(&data->fattr); |
6e4efd56 | 229 | } |
1da177e4 | 230 | |
9c7e1b3d | 231 | static int nfs_do_read(struct nfs_pgio_data *data, |
493292dd | 232 | const struct rpc_call_ops *call_ops) |
6e4efd56 | 233 | { |
cd841605 | 234 | struct inode *inode = data->header->inode; |
6e4efd56 | 235 | |
9f0ec176 | 236 | return nfs_initiate_read(NFS_CLIENT(inode), data, call_ops, 0); |
1da177e4 LT |
237 | } |
238 | ||
275acaaf TM |
239 | static int |
240 | nfs_do_multiple_reads(struct list_head *head, | |
493292dd | 241 | const struct rpc_call_ops *call_ops) |
275acaaf | 242 | { |
9c7e1b3d | 243 | struct nfs_pgio_data *data; |
275acaaf TM |
244 | int ret = 0; |
245 | ||
246 | while (!list_empty(head)) { | |
247 | int ret2; | |
248 | ||
9c7e1b3d | 249 | data = list_first_entry(head, struct nfs_pgio_data, list); |
275acaaf TM |
250 | list_del_init(&data->list); |
251 | ||
493292dd | 252 | ret2 = nfs_do_read(data, call_ops); |
275acaaf TM |
253 | if (ret == 0) |
254 | ret = ret2; | |
255 | } | |
256 | return ret; | |
257 | } | |
258 | ||
061ae2ed | 259 | static void |
1da177e4 LT |
260 | nfs_async_read_error(struct list_head *head) |
261 | { | |
262 | struct nfs_page *req; | |
263 | ||
264 | while (!list_empty(head)) { | |
265 | req = nfs_list_entry(head->next); | |
266 | nfs_list_remove_request(req); | |
1da177e4 LT |
267 | nfs_readpage_release(req); |
268 | } | |
269 | } | |
270 | ||
061ae2ed FI |
271 | static const struct nfs_pgio_completion_ops nfs_async_read_completion_ops = { |
272 | .error_cleanup = nfs_async_read_error, | |
273 | .completion = nfs_read_completion, | |
274 | }; | |
275 | ||
25b11dcd TM |
276 | static void nfs_pagein_error(struct nfs_pageio_descriptor *desc, |
277 | struct nfs_pgio_header *hdr) | |
278 | { | |
279 | set_bit(NFS_IOHDR_REDO, &hdr->flags); | |
280 | while (!list_empty(&hdr->rpc_list)) { | |
9c7e1b3d AS |
281 | struct nfs_pgio_data *data = list_first_entry(&hdr->rpc_list, |
282 | struct nfs_pgio_data, list); | |
25b11dcd | 283 | list_del(&data->list); |
00bfa30a | 284 | nfs_pgio_data_release(data); |
25b11dcd TM |
285 | } |
286 | desc->pg_completion_ops->error_cleanup(&desc->pg_list); | |
287 | } | |
288 | ||
1da177e4 LT |
289 | /* |
290 | * Generate multiple requests to fill a single page. | |
291 | * | |
292 | * We optimize to reduce the number of read operations on the wire. If we | |
293 | * detect that we're reading a page, or an area of a page, that is past the | |
294 | * end of file, we do not generate NFS read operations but just clear the | |
295 | * parts of the page that would have come back zero from the server anyway. | |
296 | * | |
297 | * We rely on the cached value of i_size to make this determination; another | |
298 | * client can fill pages on the server past our cached end-of-file, but we | |
299 | * won't see the new data until our attribute cache is updated. This is more | |
300 | * or less conventional NFS client behavior. | |
301 | */ | |
4db6e0b7 FI |
302 | static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc, |
303 | struct nfs_pgio_header *hdr) | |
1da177e4 | 304 | { |
4db6e0b7 | 305 | struct nfs_page *req = hdr->req; |
1da177e4 | 306 | struct page *page = req->wb_page; |
9c7e1b3d | 307 | struct nfs_pgio_data *data; |
d097971d | 308 | size_t rsize = desc->pg_bsize, nbytes; |
e9f7bee1 | 309 | unsigned int offset; |
1da177e4 | 310 | |
275acaaf | 311 | offset = 0; |
c76069bd | 312 | nbytes = desc->pg_count; |
e9f7bee1 TM |
313 | do { |
314 | size_t len = min(nbytes,rsize); | |
315 | ||
00bfa30a | 316 | data = nfs_pgio_data_alloc(hdr, 1); |
25b11dcd TM |
317 | if (!data) { |
318 | nfs_pagein_error(desc, hdr); | |
319 | return -ENOMEM; | |
320 | } | |
30dd374f | 321 | data->pages.pagevec[0] = page; |
4db6e0b7 FI |
322 | nfs_read_rpcsetup(data, len, offset); |
323 | list_add(&data->list, &hdr->rpc_list); | |
e9f7bee1 | 324 | nbytes -= len; |
275acaaf | 325 | offset += len; |
9146ab50 | 326 | } while (nbytes != 0); |
25b11dcd TM |
327 | |
328 | nfs_list_remove_request(req); | |
329 | nfs_list_add_request(req, &hdr->pages); | |
4db6e0b7 | 330 | desc->pg_rpc_callops = &nfs_read_common_ops; |
9146ab50 | 331 | return 0; |
1da177e4 LT |
332 | } |
333 | ||
4db6e0b7 FI |
334 | static int nfs_pagein_one(struct nfs_pageio_descriptor *desc, |
335 | struct nfs_pgio_header *hdr) | |
1da177e4 LT |
336 | { |
337 | struct nfs_page *req; | |
338 | struct page **pages; | |
9c7e1b3d | 339 | struct nfs_pgio_data *data; |
c76069bd | 340 | struct list_head *head = &desc->pg_list; |
1da177e4 | 341 | |
00bfa30a | 342 | data = nfs_pgio_data_alloc(hdr, nfs_page_array_len(desc->pg_base, |
4db6e0b7 FI |
343 | desc->pg_count)); |
344 | if (!data) { | |
25b11dcd | 345 | nfs_pagein_error(desc, hdr); |
9146ab50 | 346 | return -ENOMEM; |
bae724ef | 347 | } |
1da177e4 | 348 | |
30dd374f | 349 | pages = data->pages.pagevec; |
1da177e4 LT |
350 | while (!list_empty(head)) { |
351 | req = nfs_list_entry(head->next); | |
352 | nfs_list_remove_request(req); | |
4db6e0b7 | 353 | nfs_list_add_request(req, &hdr->pages); |
1da177e4 | 354 | *pages++ = req->wb_page; |
1da177e4 | 355 | } |
1da177e4 | 356 | |
4db6e0b7 FI |
357 | nfs_read_rpcsetup(data, desc->pg_count, 0); |
358 | list_add(&data->list, &hdr->rpc_list); | |
359 | desc->pg_rpc_callops = &nfs_read_common_ops; | |
9146ab50 | 360 | return 0; |
1da177e4 LT |
361 | } |
362 | ||
4db6e0b7 FI |
363 | int nfs_generic_pagein(struct nfs_pageio_descriptor *desc, |
364 | struct nfs_pgio_header *hdr) | |
493292dd TM |
365 | { |
366 | if (desc->pg_bsize < PAGE_CACHE_SIZE) | |
4db6e0b7 FI |
367 | return nfs_pagein_multi(desc, hdr); |
368 | return nfs_pagein_one(desc, hdr); | |
493292dd | 369 | } |
89d77c8f | 370 | EXPORT_SYMBOL_GPL(nfs_generic_pagein); |
493292dd TM |
371 | |
372 | static int nfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc) | |
1751c363 | 373 | { |
c0752cdf | 374 | struct nfs_rw_header *rhdr; |
4db6e0b7 | 375 | struct nfs_pgio_header *hdr; |
275acaaf TM |
376 | int ret; |
377 | ||
4db6e0b7 FI |
378 | rhdr = nfs_readhdr_alloc(); |
379 | if (!rhdr) { | |
061ae2ed | 380 | desc->pg_completion_ops->error_cleanup(&desc->pg_list); |
4db6e0b7 FI |
381 | return -ENOMEM; |
382 | } | |
383 | hdr = &rhdr->header; | |
384 | nfs_pgheader_init(desc, hdr, nfs_readhdr_free); | |
385 | atomic_inc(&hdr->refcnt); | |
386 | ret = nfs_generic_pagein(desc, hdr); | |
50828d7e | 387 | if (ret == 0) |
4db6e0b7 FI |
388 | ret = nfs_do_multiple_reads(&hdr->rpc_list, |
389 | desc->pg_rpc_callops); | |
4db6e0b7 | 390 | if (atomic_dec_and_test(&hdr->refcnt)) |
061ae2ed | 391 | hdr->completion_ops->completion(hdr); |
275acaaf | 392 | return ret; |
1751c363 | 393 | } |
1751c363 TM |
394 | |
395 | static const struct nfs_pageio_ops nfs_pageio_read_ops = { | |
396 | .pg_test = nfs_generic_pg_test, | |
397 | .pg_doio = nfs_generic_pg_readpages, | |
398 | }; | |
399 | ||
0b671301 TM |
400 | /* |
401 | * This is the callback from RPC telling us whether a reply was | |
402 | * received or some error occurred (timeout or socket shutdown). | |
403 | */ | |
9c7e1b3d | 404 | int nfs_readpage_result(struct rpc_task *task, struct nfs_pgio_data *data) |
0b671301 | 405 | { |
cd841605 | 406 | struct inode *inode = data->header->inode; |
0b671301 TM |
407 | int status; |
408 | ||
3110ff80 | 409 | dprintk("NFS: %s: %5u, (status %d)\n", __func__, task->tk_pid, |
0b671301 TM |
410 | task->tk_status); |
411 | ||
cd841605 | 412 | status = NFS_PROTO(inode)->read_done(task, data); |
0b671301 TM |
413 | if (status != 0) |
414 | return status; | |
415 | ||
cd841605 | 416 | nfs_add_stats(inode, NFSIOS_SERVERREADBYTES, data->res.count); |
0b671301 TM |
417 | |
418 | if (task->tk_status == -ESTALE) { | |
cd841605 FI |
419 | set_bit(NFS_INO_STALE, &NFS_I(inode)->flags); |
420 | nfs_mark_for_revalidate(inode); | |
0b671301 | 421 | } |
0b671301 TM |
422 | return 0; |
423 | } | |
424 | ||
9c7e1b3d | 425 | static void nfs_readpage_retry(struct rpc_task *task, struct nfs_pgio_data *data) |
0b671301 | 426 | { |
3c6b899c | 427 | struct nfs_pgio_args *argp = &data->args; |
9137bdf3 | 428 | struct nfs_pgio_res *resp = &data->res; |
0b671301 | 429 | |
0b671301 | 430 | /* This is a short read! */ |
cd841605 | 431 | nfs_inc_stats(data->header->inode, NFSIOS_SHORTREAD); |
0b671301 | 432 | /* Has the server at least made some progress? */ |
4db6e0b7 FI |
433 | if (resp->count == 0) { |
434 | nfs_set_pgio_error(data->header, -EIO, argp->offset); | |
d61e612a | 435 | return; |
4db6e0b7 | 436 | } |
0b671301 | 437 | /* Yes, so retry the read at the end of the data */ |
cbdabc7f | 438 | data->mds_offset += resp->count; |
0b671301 TM |
439 | argp->offset += resp->count; |
440 | argp->pgbase += resp->count; | |
441 | argp->count -= resp->count; | |
d00c5d43 | 442 | rpc_restart_call_prepare(task); |
0b671301 TM |
443 | } |
444 | ||
4db6e0b7 | 445 | static void nfs_readpage_result_common(struct rpc_task *task, void *calldata) |
1da177e4 | 446 | { |
9c7e1b3d | 447 | struct nfs_pgio_data *data = calldata; |
4db6e0b7 FI |
448 | struct nfs_pgio_header *hdr = data->header; |
449 | ||
450 | /* Note the only returns of nfs_readpage_result are 0 and -EAGAIN */ | |
ec06c096 TM |
451 | if (nfs_readpage_result(task, data) != 0) |
452 | return; | |
fdd1e74c | 453 | if (task->tk_status < 0) |
4db6e0b7 FI |
454 | nfs_set_pgio_error(hdr, task->tk_status, data->args.offset); |
455 | else if (data->res.eof) { | |
456 | loff_t bound; | |
457 | ||
458 | bound = data->args.offset + data->res.count; | |
459 | spin_lock(&hdr->lock); | |
460 | if (bound < hdr->io_start + hdr->good_bytes) { | |
461 | set_bit(NFS_IOHDR_EOF, &hdr->flags); | |
462 | clear_bit(NFS_IOHDR_ERROR, &hdr->flags); | |
463 | hdr->good_bytes = bound - hdr->io_start; | |
464 | } | |
465 | spin_unlock(&hdr->lock); | |
466 | } else if (data->res.count != data->args.count) | |
467 | nfs_readpage_retry(task, data); | |
fdd1e74c TM |
468 | } |
469 | ||
4db6e0b7 | 470 | static void nfs_readpage_release_common(void *calldata) |
fdd1e74c | 471 | { |
00bfa30a | 472 | nfs_pgio_data_release(calldata); |
1da177e4 LT |
473 | } |
474 | ||
f11c88af AA |
475 | void nfs_read_prepare(struct rpc_task *task, void *calldata) |
476 | { | |
9c7e1b3d | 477 | struct nfs_pgio_data *data = calldata; |
ef1820f9 N |
478 | int err; |
479 | err = NFS_PROTO(data->header->inode)->read_rpc_prepare(task, data); | |
480 | if (err) | |
481 | rpc_exit(task, err); | |
f11c88af | 482 | } |
f11c88af | 483 | |
4db6e0b7 | 484 | static const struct rpc_call_ops nfs_read_common_ops = { |
f11c88af | 485 | .rpc_call_prepare = nfs_read_prepare, |
4db6e0b7 FI |
486 | .rpc_call_done = nfs_readpage_result_common, |
487 | .rpc_release = nfs_readpage_release_common, | |
ec06c096 TM |
488 | }; |
489 | ||
1da177e4 LT |
490 | /* |
491 | * Read a page over NFS. | |
492 | * We read the page synchronously in the following case: | |
493 | * - The error flag is set for this page. This happens only when a | |
494 | * previous async read operation failed. | |
495 | */ | |
496 | int nfs_readpage(struct file *file, struct page *page) | |
497 | { | |
498 | struct nfs_open_context *ctx; | |
d56b4ddf | 499 | struct inode *inode = page_file_mapping(page)->host; |
1da177e4 LT |
500 | int error; |
501 | ||
502 | dprintk("NFS: nfs_readpage (%p %ld@%lu)\n", | |
d56b4ddf | 503 | page, PAGE_CACHE_SIZE, page_file_index(page)); |
91d5b470 CL |
504 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGE); |
505 | nfs_add_stats(inode, NFSIOS_READPAGES, 1); | |
506 | ||
1da177e4 LT |
507 | /* |
508 | * Try to flush any pending writes to the file.. | |
509 | * | |
510 | * NOTE! Because we own the page lock, there cannot | |
511 | * be any new pending writes generated at this point | |
512 | * for this page (other pages can be written to). | |
513 | */ | |
514 | error = nfs_wb_page(inode, page); | |
515 | if (error) | |
de05a0cc TM |
516 | goto out_unlock; |
517 | if (PageUptodate(page)) | |
518 | goto out_unlock; | |
1da177e4 | 519 | |
5f004cf2 TM |
520 | error = -ESTALE; |
521 | if (NFS_STALE(inode)) | |
de05a0cc | 522 | goto out_unlock; |
5f004cf2 | 523 | |
1da177e4 | 524 | if (file == NULL) { |
cf1308ff | 525 | error = -EBADF; |
d530838b | 526 | ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
1da177e4 | 527 | if (ctx == NULL) |
de05a0cc | 528 | goto out_unlock; |
1da177e4 | 529 | } else |
cd3758e3 | 530 | ctx = get_nfs_open_context(nfs_file_open_context(file)); |
1da177e4 | 531 | |
9a9fc1c0 DH |
532 | if (!IS_SYNC(inode)) { |
533 | error = nfs_readpage_from_fscache(ctx, inode, page); | |
534 | if (error == 0) | |
535 | goto out; | |
536 | } | |
537 | ||
8e0969f0 TM |
538 | error = nfs_readpage_async(ctx, inode, page); |
539 | ||
9a9fc1c0 | 540 | out: |
1da177e4 LT |
541 | put_nfs_open_context(ctx); |
542 | return error; | |
de05a0cc | 543 | out_unlock: |
1da177e4 LT |
544 | unlock_page(page); |
545 | return error; | |
546 | } | |
547 | ||
548 | struct nfs_readdesc { | |
8b09bee3 | 549 | struct nfs_pageio_descriptor *pgio; |
1da177e4 LT |
550 | struct nfs_open_context *ctx; |
551 | }; | |
552 | ||
553 | static int | |
554 | readpage_async_filler(void *data, struct page *page) | |
555 | { | |
556 | struct nfs_readdesc *desc = (struct nfs_readdesc *)data; | |
d56b4ddf | 557 | struct inode *inode = page_file_mapping(page)->host; |
1da177e4 LT |
558 | struct nfs_page *new; |
559 | unsigned int len; | |
de05a0cc TM |
560 | int error; |
561 | ||
49a70f27 | 562 | len = nfs_page_length(page); |
1da177e4 LT |
563 | if (len == 0) |
564 | return nfs_return_empty_page(page); | |
de05a0cc | 565 | |
1da177e4 | 566 | new = nfs_create_request(desc->ctx, inode, page, 0, len); |
de05a0cc TM |
567 | if (IS_ERR(new)) |
568 | goto out_error; | |
569 | ||
1da177e4 | 570 | if (len < PAGE_CACHE_SIZE) |
eebd2aa3 | 571 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
f8512ad0 FI |
572 | if (!nfs_pageio_add_request(desc->pgio, new)) { |
573 | error = desc->pgio->pg_error; | |
574 | goto out_unlock; | |
575 | } | |
1da177e4 | 576 | return 0; |
de05a0cc TM |
577 | out_error: |
578 | error = PTR_ERR(new); | |
de05a0cc TM |
579 | out_unlock: |
580 | unlock_page(page); | |
581 | return error; | |
1da177e4 LT |
582 | } |
583 | ||
584 | int nfs_readpages(struct file *filp, struct address_space *mapping, | |
585 | struct list_head *pages, unsigned nr_pages) | |
586 | { | |
8b09bee3 | 587 | struct nfs_pageio_descriptor pgio; |
1da177e4 | 588 | struct nfs_readdesc desc = { |
8b09bee3 | 589 | .pgio = &pgio, |
1da177e4 LT |
590 | }; |
591 | struct inode *inode = mapping->host; | |
8b09bee3 | 592 | unsigned long npages; |
5f004cf2 | 593 | int ret = -ESTALE; |
1da177e4 | 594 | |
1e8968c5 | 595 | dprintk("NFS: nfs_readpages (%s/%Lu %d)\n", |
1da177e4 | 596 | inode->i_sb->s_id, |
1e8968c5 | 597 | (unsigned long long)NFS_FILEID(inode), |
1da177e4 | 598 | nr_pages); |
91d5b470 | 599 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGES); |
1da177e4 | 600 | |
5f004cf2 TM |
601 | if (NFS_STALE(inode)) |
602 | goto out; | |
603 | ||
1da177e4 | 604 | if (filp == NULL) { |
d530838b | 605 | desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
1da177e4 LT |
606 | if (desc.ctx == NULL) |
607 | return -EBADF; | |
608 | } else | |
cd3758e3 | 609 | desc.ctx = get_nfs_open_context(nfs_file_open_context(filp)); |
9a9fc1c0 DH |
610 | |
611 | /* attempt to read as many of the pages as possible from the cache | |
612 | * - this returns -ENOBUFS immediately if the cookie is negative | |
613 | */ | |
614 | ret = nfs_readpages_from_fscache(desc.ctx, inode, mapping, | |
615 | pages, &nr_pages); | |
616 | if (ret == 0) | |
617 | goto read_complete; /* all pages were read */ | |
618 | ||
fab5fc25 CH |
619 | nfs_pageio_init_read(&pgio, inode, false, |
620 | &nfs_async_read_completion_ops); | |
8b09bee3 | 621 | |
1da177e4 | 622 | ret = read_cache_pages(mapping, pages, readpage_async_filler, &desc); |
8b09bee3 TM |
623 | |
624 | nfs_pageio_complete(&pgio); | |
2701d086 | 625 | NFS_I(inode)->read_io += pgio.pg_bytes_written; |
8b09bee3 TM |
626 | npages = (pgio.pg_bytes_written + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; |
627 | nfs_add_stats(inode, NFSIOS_READPAGES, npages); | |
9a9fc1c0 | 628 | read_complete: |
1da177e4 | 629 | put_nfs_open_context(desc.ctx); |
5f004cf2 | 630 | out: |
1da177e4 LT |
631 | return ret; |
632 | } | |
633 | ||
f7b422b1 | 634 | int __init nfs_init_readpagecache(void) |
1da177e4 LT |
635 | { |
636 | nfs_rdata_cachep = kmem_cache_create("nfs_read_data", | |
c0752cdf | 637 | sizeof(struct nfs_rw_header), |
1da177e4 | 638 | 0, SLAB_HWCACHE_ALIGN, |
20c2df83 | 639 | NULL); |
1da177e4 LT |
640 | if (nfs_rdata_cachep == NULL) |
641 | return -ENOMEM; | |
642 | ||
1da177e4 LT |
643 | return 0; |
644 | } | |
645 | ||
266bee88 | 646 | void nfs_destroy_readpagecache(void) |
1da177e4 | 647 | { |
1a1d92c1 | 648 | kmem_cache_destroy(nfs_rdata_cachep); |
1da177e4 | 649 | } |