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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> | |
64419a9b | 21 | #include <linux/module.h> |
1da177e4 | 22 | |
bae724ef | 23 | #include "pnfs.h" |
1da177e4 | 24 | |
f11c88af | 25 | #include "nfs4_fs.h" |
49a70f27 | 26 | #include "internal.h" |
91d5b470 | 27 | #include "iostat.h" |
9a9fc1c0 | 28 | #include "fscache.h" |
91d5b470 | 29 | |
1da177e4 LT |
30 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE |
31 | ||
1751c363 | 32 | static const struct nfs_pageio_ops nfs_pageio_read_ops; |
4db6e0b7 | 33 | static const struct rpc_call_ops nfs_read_common_ops; |
061ae2ed | 34 | static const struct nfs_pgio_completion_ops nfs_async_read_completion_ops; |
1da177e4 | 35 | |
e18b890b | 36 | static struct kmem_cache *nfs_rdata_cachep; |
1da177e4 | 37 | |
4db6e0b7 | 38 | struct nfs_read_header *nfs_readhdr_alloc() |
3feb2d49 | 39 | { |
4db6e0b7 | 40 | struct nfs_read_header *rhdr; |
3feb2d49 | 41 | |
4db6e0b7 FI |
42 | rhdr = kmem_cache_zalloc(nfs_rdata_cachep, GFP_KERNEL); |
43 | if (rhdr) { | |
44 | struct nfs_pgio_header *hdr = &rhdr->header; | |
cd841605 FI |
45 | |
46 | INIT_LIST_HEAD(&hdr->pages); | |
4db6e0b7 FI |
47 | INIT_LIST_HEAD(&hdr->rpc_list); |
48 | spin_lock_init(&hdr->lock); | |
49 | atomic_set(&hdr->refcnt, 0); | |
50 | } | |
51 | return rhdr; | |
52 | } | |
53 | ||
584aa810 FI |
54 | static struct nfs_read_data *nfs_readdata_alloc(struct nfs_pgio_header *hdr, |
55 | unsigned int pagecount) | |
4db6e0b7 FI |
56 | { |
57 | struct nfs_read_data *data, *prealloc; | |
58 | ||
59 | prealloc = &container_of(hdr, struct nfs_read_header, header)->rpc_data; | |
60 | if (prealloc->header == NULL) | |
61 | data = prealloc; | |
62 | else | |
63 | data = kzalloc(sizeof(*data), GFP_KERNEL); | |
64 | if (!data) | |
65 | goto out; | |
66 | ||
67 | if (nfs_pgarray_set(&data->pages, pagecount)) { | |
cd841605 | 68 | data->header = hdr; |
4db6e0b7 FI |
69 | atomic_inc(&hdr->refcnt); |
70 | } else { | |
71 | if (data != prealloc) | |
72 | kfree(data); | |
73 | data = NULL; | |
3feb2d49 | 74 | } |
4db6e0b7 FI |
75 | out: |
76 | return data; | |
3feb2d49 TM |
77 | } |
78 | ||
cd841605 | 79 | void nfs_readhdr_free(struct nfs_pgio_header *hdr) |
3feb2d49 | 80 | { |
cd841605 FI |
81 | struct nfs_read_header *rhdr = container_of(hdr, struct nfs_read_header, header); |
82 | ||
83 | kmem_cache_free(nfs_rdata_cachep, rhdr); | |
3feb2d49 TM |
84 | } |
85 | ||
493292dd | 86 | void nfs_readdata_release(struct nfs_read_data *rdata) |
1da177e4 | 87 | { |
4db6e0b7 FI |
88 | struct nfs_pgio_header *hdr = rdata->header; |
89 | struct nfs_read_header *read_header = container_of(hdr, struct nfs_read_header, header); | |
90 | ||
383ba719 | 91 | put_nfs_open_context(rdata->args.context); |
30dd374f FI |
92 | if (rdata->pages.pagevec != rdata->pages.page_array) |
93 | kfree(rdata->pages.pagevec); | |
4db6e0b7 FI |
94 | if (rdata != &read_header->rpc_data) |
95 | kfree(rdata); | |
96 | else | |
97 | rdata->header = NULL; | |
98 | if (atomic_dec_and_test(&hdr->refcnt)) | |
061ae2ed | 99 | hdr->completion_ops->completion(hdr); |
1da177e4 LT |
100 | } |
101 | ||
1da177e4 LT |
102 | static |
103 | int nfs_return_empty_page(struct page *page) | |
104 | { | |
eebd2aa3 | 105 | zero_user(page, 0, PAGE_CACHE_SIZE); |
1da177e4 LT |
106 | SetPageUptodate(page); |
107 | unlock_page(page); | |
108 | return 0; | |
109 | } | |
110 | ||
62e4a769 | 111 | void nfs_pageio_init_read_mds(struct nfs_pageio_descriptor *pgio, |
061ae2ed FI |
112 | struct inode *inode, |
113 | const struct nfs_pgio_completion_ops *compl_ops) | |
1751c363 | 114 | { |
061ae2ed | 115 | nfs_pageio_init(pgio, inode, &nfs_pageio_read_ops, compl_ops, |
1751c363 TM |
116 | NFS_SERVER(inode)->rsize, 0); |
117 | } | |
118 | ||
493292dd TM |
119 | void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio) |
120 | { | |
121 | pgio->pg_ops = &nfs_pageio_read_ops; | |
122 | pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->rsize; | |
123 | } | |
1f945357 | 124 | EXPORT_SYMBOL_GPL(nfs_pageio_reset_read_mds); |
493292dd | 125 | |
584aa810 FI |
126 | void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, |
127 | struct inode *inode, | |
128 | const struct nfs_pgio_completion_ops *compl_ops) | |
1751c363 | 129 | { |
061ae2ed FI |
130 | if (!pnfs_pageio_init_read(pgio, inode, compl_ops)) |
131 | nfs_pageio_init_read_mds(pgio, inode, compl_ops); | |
1751c363 TM |
132 | } |
133 | ||
f42b293d DH |
134 | int nfs_readpage_async(struct nfs_open_context *ctx, struct inode *inode, |
135 | struct page *page) | |
1da177e4 | 136 | { |
1da177e4 LT |
137 | struct nfs_page *new; |
138 | unsigned int len; | |
c76069bd | 139 | struct nfs_pageio_descriptor pgio; |
1da177e4 | 140 | |
49a70f27 | 141 | len = nfs_page_length(page); |
1da177e4 LT |
142 | if (len == 0) |
143 | return nfs_return_empty_page(page); | |
144 | new = nfs_create_request(ctx, inode, page, 0, len); | |
145 | if (IS_ERR(new)) { | |
146 | unlock_page(page); | |
147 | return PTR_ERR(new); | |
148 | } | |
149 | if (len < PAGE_CACHE_SIZE) | |
eebd2aa3 | 150 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
1da177e4 | 151 | |
061ae2ed | 152 | nfs_pageio_init_read(&pgio, inode, &nfs_async_read_completion_ops); |
d8007d4d | 153 | nfs_pageio_add_request(&pgio, new); |
1751c363 | 154 | nfs_pageio_complete(&pgio); |
1da177e4 LT |
155 | return 0; |
156 | } | |
157 | ||
158 | static void nfs_readpage_release(struct nfs_page *req) | |
159 | { | |
3d4ff43d | 160 | struct inode *d_inode = req->wb_context->dentry->d_inode; |
7f8e05f6 DH |
161 | |
162 | if (PageUptodate(req->wb_page)) | |
163 | nfs_readpage_to_fscache(d_inode, req->wb_page, 0); | |
164 | ||
1da177e4 LT |
165 | unlock_page(req->wb_page); |
166 | ||
1da177e4 | 167 | dprintk("NFS: read done (%s/%Ld %d@%Ld)\n", |
3d4ff43d AV |
168 | req->wb_context->dentry->d_inode->i_sb->s_id, |
169 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1da177e4 LT |
170 | req->wb_bytes, |
171 | (long long)req_offset(req)); | |
10d2c46f | 172 | nfs_release_request(req); |
1da177e4 LT |
173 | } |
174 | ||
4db6e0b7 | 175 | /* Note io was page aligned */ |
061ae2ed | 176 | static void nfs_read_completion(struct nfs_pgio_header *hdr) |
4db6e0b7 FI |
177 | { |
178 | unsigned long bytes = 0; | |
179 | ||
180 | if (test_bit(NFS_IOHDR_REDO, &hdr->flags)) | |
181 | goto out; | |
182 | if (!test_bit(NFS_IOHDR_ERROR, &hdr->flags)) { | |
183 | while (!list_empty(&hdr->pages)) { | |
184 | struct nfs_page *req = nfs_list_entry(hdr->pages.next); | |
185 | struct page *page = req->wb_page; | |
186 | ||
187 | if (test_bit(NFS_IOHDR_EOF, &hdr->flags)) { | |
188 | if (bytes > hdr->good_bytes) | |
189 | zero_user(page, 0, PAGE_SIZE); | |
190 | else if (hdr->good_bytes - bytes < PAGE_SIZE) | |
191 | zero_user_segment(page, | |
192 | hdr->good_bytes & ~PAGE_MASK, | |
193 | PAGE_SIZE); | |
194 | } | |
195 | SetPageUptodate(page); | |
196 | nfs_list_remove_request(req); | |
197 | nfs_readpage_release(req); | |
198 | bytes += PAGE_SIZE; | |
199 | } | |
200 | } else { | |
201 | while (!list_empty(&hdr->pages)) { | |
202 | struct nfs_page *req = nfs_list_entry(hdr->pages.next); | |
203 | ||
204 | bytes += req->wb_bytes; | |
205 | if (bytes <= hdr->good_bytes) | |
206 | SetPageUptodate(req->wb_page); | |
207 | nfs_list_remove_request(req); | |
208 | nfs_readpage_release(req); | |
209 | } | |
210 | } | |
211 | out: | |
212 | hdr->release(hdr); | |
213 | } | |
214 | ||
c5996c4e FI |
215 | int nfs_initiate_read(struct rpc_clnt *clnt, |
216 | struct nfs_read_data *data, | |
64419a9b | 217 | const struct rpc_call_ops *call_ops) |
1da177e4 | 218 | { |
cd841605 | 219 | struct inode *inode = data->header->inode; |
84115e1c | 220 | int swap_flags = IS_SWAPFILE(inode) ? NFS_RPC_SWAPFLAGS : 0; |
07737691 | 221 | struct rpc_task *task; |
bdc7f021 TM |
222 | struct rpc_message msg = { |
223 | .rpc_argp = &data->args, | |
224 | .rpc_resp = &data->res, | |
cd841605 | 225 | .rpc_cred = data->header->cred, |
bdc7f021 | 226 | }; |
84115e1c | 227 | struct rpc_task_setup task_setup_data = { |
07737691 | 228 | .task = &data->task, |
64419a9b | 229 | .rpc_client = clnt, |
bdc7f021 | 230 | .rpc_message = &msg, |
84115e1c TM |
231 | .callback_ops = call_ops, |
232 | .callback_data = data, | |
101070ca | 233 | .workqueue = nfsiod_workqueue, |
84115e1c TM |
234 | .flags = RPC_TASK_ASYNC | swap_flags, |
235 | }; | |
1da177e4 | 236 | |
64419a9b AA |
237 | /* Set up the initial task struct. */ |
238 | NFS_PROTO(inode)->read_setup(data, &msg); | |
239 | ||
240 | dprintk("NFS: %5u initiated read call (req %s/%lld, %u bytes @ " | |
241 | "offset %llu)\n", | |
242 | data->task.tk_pid, | |
243 | inode->i_sb->s_id, | |
244 | (long long)NFS_FILEID(inode), | |
245 | data->args.count, | |
246 | (unsigned long long)data->args.offset); | |
247 | ||
248 | task = rpc_run_task(&task_setup_data); | |
249 | if (IS_ERR(task)) | |
250 | return PTR_ERR(task); | |
251 | rpc_put_task(task); | |
252 | return 0; | |
253 | } | |
dc70d7b3 | 254 | EXPORT_SYMBOL_GPL(nfs_initiate_read); |
64419a9b AA |
255 | |
256 | /* | |
257 | * Set up the NFS read request struct | |
258 | */ | |
4db6e0b7 | 259 | static void nfs_read_rpcsetup(struct nfs_read_data *data, |
6e4efd56 | 260 | unsigned int count, unsigned int offset) |
64419a9b | 261 | { |
4db6e0b7 | 262 | struct nfs_page *req = data->header->req; |
1da177e4 | 263 | |
4db6e0b7 | 264 | data->args.fh = NFS_FH(data->header->inode); |
1da177e4 LT |
265 | data->args.offset = req_offset(req) + offset; |
266 | data->args.pgbase = req->wb_pgbase + offset; | |
30dd374f | 267 | data->args.pages = data->pages.pagevec; |
1da177e4 | 268 | data->args.count = count; |
383ba719 | 269 | data->args.context = get_nfs_open_context(req->wb_context); |
f11ac8db | 270 | data->args.lock_context = req->wb_lock_context; |
1da177e4 LT |
271 | |
272 | data->res.fattr = &data->fattr; | |
273 | data->res.count = count; | |
274 | data->res.eof = 0; | |
0e574af1 | 275 | nfs_fattr_init(&data->fattr); |
6e4efd56 | 276 | } |
1da177e4 | 277 | |
6e4efd56 | 278 | static int nfs_do_read(struct nfs_read_data *data, |
493292dd | 279 | const struct rpc_call_ops *call_ops) |
6e4efd56 | 280 | { |
cd841605 | 281 | struct inode *inode = data->header->inode; |
6e4efd56 | 282 | |
c5996c4e | 283 | return nfs_initiate_read(NFS_CLIENT(inode), data, call_ops); |
1da177e4 LT |
284 | } |
285 | ||
275acaaf TM |
286 | static int |
287 | nfs_do_multiple_reads(struct list_head *head, | |
493292dd | 288 | const struct rpc_call_ops *call_ops) |
275acaaf TM |
289 | { |
290 | struct nfs_read_data *data; | |
291 | int ret = 0; | |
292 | ||
293 | while (!list_empty(head)) { | |
294 | int ret2; | |
295 | ||
4db6e0b7 | 296 | data = list_first_entry(head, struct nfs_read_data, list); |
275acaaf TM |
297 | list_del_init(&data->list); |
298 | ||
493292dd | 299 | ret2 = nfs_do_read(data, call_ops); |
275acaaf TM |
300 | if (ret == 0) |
301 | ret = ret2; | |
302 | } | |
303 | return ret; | |
304 | } | |
305 | ||
061ae2ed | 306 | static void |
1da177e4 LT |
307 | nfs_async_read_error(struct list_head *head) |
308 | { | |
309 | struct nfs_page *req; | |
310 | ||
311 | while (!list_empty(head)) { | |
312 | req = nfs_list_entry(head->next); | |
313 | nfs_list_remove_request(req); | |
1da177e4 LT |
314 | nfs_readpage_release(req); |
315 | } | |
316 | } | |
317 | ||
061ae2ed FI |
318 | static const struct nfs_pgio_completion_ops nfs_async_read_completion_ops = { |
319 | .error_cleanup = nfs_async_read_error, | |
320 | .completion = nfs_read_completion, | |
321 | }; | |
322 | ||
1da177e4 LT |
323 | /* |
324 | * Generate multiple requests to fill a single page. | |
325 | * | |
326 | * We optimize to reduce the number of read operations on the wire. If we | |
327 | * detect that we're reading a page, or an area of a page, that is past the | |
328 | * end of file, we do not generate NFS read operations but just clear the | |
329 | * parts of the page that would have come back zero from the server anyway. | |
330 | * | |
331 | * We rely on the cached value of i_size to make this determination; another | |
332 | * client can fill pages on the server past our cached end-of-file, but we | |
333 | * won't see the new data until our attribute cache is updated. This is more | |
334 | * or less conventional NFS client behavior. | |
335 | */ | |
4db6e0b7 FI |
336 | static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc, |
337 | struct nfs_pgio_header *hdr) | |
1da177e4 | 338 | { |
4db6e0b7 | 339 | struct nfs_page *req = hdr->req; |
1da177e4 LT |
340 | struct page *page = req->wb_page; |
341 | struct nfs_read_data *data; | |
d097971d | 342 | size_t rsize = desc->pg_bsize, nbytes; |
e9f7bee1 | 343 | unsigned int offset; |
1da177e4 LT |
344 | |
345 | nfs_list_remove_request(req); | |
4db6e0b7 | 346 | nfs_list_add_request(req, &hdr->pages); |
1da177e4 | 347 | |
275acaaf | 348 | offset = 0; |
c76069bd | 349 | nbytes = desc->pg_count; |
e9f7bee1 TM |
350 | do { |
351 | size_t len = min(nbytes,rsize); | |
352 | ||
4db6e0b7 FI |
353 | data = nfs_readdata_alloc(hdr, 1); |
354 | if (!data) | |
1da177e4 | 355 | goto out_bad; |
30dd374f | 356 | data->pages.pagevec[0] = page; |
4db6e0b7 FI |
357 | nfs_read_rpcsetup(data, len, offset); |
358 | list_add(&data->list, &hdr->rpc_list); | |
e9f7bee1 | 359 | nbytes -= len; |
275acaaf | 360 | offset += len; |
9146ab50 | 361 | } while (nbytes != 0); |
4db6e0b7 | 362 | desc->pg_rpc_callops = &nfs_read_common_ops; |
9146ab50 | 363 | return 0; |
1da177e4 | 364 | out_bad: |
4db6e0b7 FI |
365 | while (!list_empty(&hdr->rpc_list)) { |
366 | data = list_first_entry(&hdr->rpc_list, struct nfs_read_data, list); | |
6e4efd56 | 367 | list_del(&data->list); |
73fb7bc7 | 368 | nfs_readdata_release(data); |
1da177e4 | 369 | } |
061ae2ed | 370 | desc->pg_completion_ops->error_cleanup(&hdr->pages); |
1da177e4 LT |
371 | return -ENOMEM; |
372 | } | |
373 | ||
4db6e0b7 FI |
374 | static int nfs_pagein_one(struct nfs_pageio_descriptor *desc, |
375 | struct nfs_pgio_header *hdr) | |
1da177e4 LT |
376 | { |
377 | struct nfs_page *req; | |
378 | struct page **pages; | |
4db6e0b7 | 379 | struct nfs_read_data *data; |
c76069bd | 380 | struct list_head *head = &desc->pg_list; |
3b609184 | 381 | int ret = 0; |
1da177e4 | 382 | |
4db6e0b7 FI |
383 | data = nfs_readdata_alloc(hdr, nfs_page_array_len(desc->pg_base, |
384 | desc->pg_count)); | |
385 | if (!data) { | |
061ae2ed | 386 | desc->pg_completion_ops->error_cleanup(head); |
9146ab50 | 387 | return -ENOMEM; |
bae724ef | 388 | } |
1da177e4 | 389 | |
30dd374f | 390 | pages = data->pages.pagevec; |
1da177e4 LT |
391 | while (!list_empty(head)) { |
392 | req = nfs_list_entry(head->next); | |
393 | nfs_list_remove_request(req); | |
4db6e0b7 | 394 | nfs_list_add_request(req, &hdr->pages); |
1da177e4 | 395 | *pages++ = req->wb_page; |
1da177e4 | 396 | } |
1da177e4 | 397 | |
4db6e0b7 FI |
398 | nfs_read_rpcsetup(data, desc->pg_count, 0); |
399 | list_add(&data->list, &hdr->rpc_list); | |
400 | desc->pg_rpc_callops = &nfs_read_common_ops; | |
9146ab50 | 401 | return 0; |
1da177e4 LT |
402 | } |
403 | ||
4db6e0b7 FI |
404 | int nfs_generic_pagein(struct nfs_pageio_descriptor *desc, |
405 | struct nfs_pgio_header *hdr) | |
493292dd TM |
406 | { |
407 | if (desc->pg_bsize < PAGE_CACHE_SIZE) | |
4db6e0b7 FI |
408 | return nfs_pagein_multi(desc, hdr); |
409 | return nfs_pagein_one(desc, hdr); | |
493292dd TM |
410 | } |
411 | ||
412 | static int nfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc) | |
1751c363 | 413 | { |
4db6e0b7 FI |
414 | struct nfs_read_header *rhdr; |
415 | struct nfs_pgio_header *hdr; | |
275acaaf TM |
416 | int ret; |
417 | ||
4db6e0b7 FI |
418 | rhdr = nfs_readhdr_alloc(); |
419 | if (!rhdr) { | |
061ae2ed | 420 | desc->pg_completion_ops->error_cleanup(&desc->pg_list); |
4db6e0b7 FI |
421 | return -ENOMEM; |
422 | } | |
423 | hdr = &rhdr->header; | |
424 | nfs_pgheader_init(desc, hdr, nfs_readhdr_free); | |
425 | atomic_inc(&hdr->refcnt); | |
426 | ret = nfs_generic_pagein(desc, hdr); | |
50828d7e | 427 | if (ret == 0) |
4db6e0b7 FI |
428 | ret = nfs_do_multiple_reads(&hdr->rpc_list, |
429 | desc->pg_rpc_callops); | |
430 | else | |
431 | set_bit(NFS_IOHDR_REDO, &hdr->flags); | |
432 | if (atomic_dec_and_test(&hdr->refcnt)) | |
061ae2ed | 433 | hdr->completion_ops->completion(hdr); |
275acaaf | 434 | return ret; |
1751c363 | 435 | } |
1751c363 TM |
436 | |
437 | static const struct nfs_pageio_ops nfs_pageio_read_ops = { | |
438 | .pg_test = nfs_generic_pg_test, | |
439 | .pg_doio = nfs_generic_pg_readpages, | |
440 | }; | |
441 | ||
0b671301 TM |
442 | /* |
443 | * This is the callback from RPC telling us whether a reply was | |
444 | * received or some error occurred (timeout or socket shutdown). | |
445 | */ | |
446 | int nfs_readpage_result(struct rpc_task *task, struct nfs_read_data *data) | |
447 | { | |
cd841605 | 448 | struct inode *inode = data->header->inode; |
0b671301 TM |
449 | int status; |
450 | ||
3110ff80 | 451 | dprintk("NFS: %s: %5u, (status %d)\n", __func__, task->tk_pid, |
0b671301 TM |
452 | task->tk_status); |
453 | ||
cd841605 | 454 | status = NFS_PROTO(inode)->read_done(task, data); |
0b671301 TM |
455 | if (status != 0) |
456 | return status; | |
457 | ||
cd841605 | 458 | nfs_add_stats(inode, NFSIOS_SERVERREADBYTES, data->res.count); |
0b671301 TM |
459 | |
460 | if (task->tk_status == -ESTALE) { | |
cd841605 FI |
461 | set_bit(NFS_INO_STALE, &NFS_I(inode)->flags); |
462 | nfs_mark_for_revalidate(inode); | |
0b671301 | 463 | } |
0b671301 TM |
464 | return 0; |
465 | } | |
466 | ||
fdd1e74c | 467 | static void nfs_readpage_retry(struct rpc_task *task, struct nfs_read_data *data) |
0b671301 TM |
468 | { |
469 | struct nfs_readargs *argp = &data->args; | |
470 | struct nfs_readres *resp = &data->res; | |
471 | ||
0b671301 | 472 | /* This is a short read! */ |
cd841605 | 473 | nfs_inc_stats(data->header->inode, NFSIOS_SHORTREAD); |
0b671301 | 474 | /* Has the server at least made some progress? */ |
4db6e0b7 FI |
475 | if (resp->count == 0) { |
476 | nfs_set_pgio_error(data->header, -EIO, argp->offset); | |
d61e612a | 477 | return; |
4db6e0b7 | 478 | } |
0b671301 | 479 | /* Yes, so retry the read at the end of the data */ |
cbdabc7f | 480 | data->mds_offset += resp->count; |
0b671301 TM |
481 | argp->offset += resp->count; |
482 | argp->pgbase += resp->count; | |
483 | argp->count -= resp->count; | |
d00c5d43 | 484 | rpc_restart_call_prepare(task); |
0b671301 TM |
485 | } |
486 | ||
4db6e0b7 | 487 | static void nfs_readpage_result_common(struct rpc_task *task, void *calldata) |
1da177e4 | 488 | { |
ec06c096 | 489 | struct nfs_read_data *data = calldata; |
4db6e0b7 FI |
490 | struct nfs_pgio_header *hdr = data->header; |
491 | ||
492 | /* Note the only returns of nfs_readpage_result are 0 and -EAGAIN */ | |
ec06c096 TM |
493 | if (nfs_readpage_result(task, data) != 0) |
494 | return; | |
fdd1e74c | 495 | if (task->tk_status < 0) |
4db6e0b7 FI |
496 | nfs_set_pgio_error(hdr, task->tk_status, data->args.offset); |
497 | else if (data->res.eof) { | |
498 | loff_t bound; | |
499 | ||
500 | bound = data->args.offset + data->res.count; | |
501 | spin_lock(&hdr->lock); | |
502 | if (bound < hdr->io_start + hdr->good_bytes) { | |
503 | set_bit(NFS_IOHDR_EOF, &hdr->flags); | |
504 | clear_bit(NFS_IOHDR_ERROR, &hdr->flags); | |
505 | hdr->good_bytes = bound - hdr->io_start; | |
506 | } | |
507 | spin_unlock(&hdr->lock); | |
508 | } else if (data->res.count != data->args.count) | |
509 | nfs_readpage_retry(task, data); | |
fdd1e74c TM |
510 | } |
511 | ||
4db6e0b7 | 512 | static void nfs_readpage_release_common(void *calldata) |
fdd1e74c | 513 | { |
4db6e0b7 | 514 | nfs_readdata_release(calldata); |
1da177e4 LT |
515 | } |
516 | ||
f11c88af AA |
517 | void nfs_read_prepare(struct rpc_task *task, void *calldata) |
518 | { | |
519 | struct nfs_read_data *data = calldata; | |
cd841605 | 520 | NFS_PROTO(data->header->inode)->read_rpc_prepare(task, data); |
f11c88af | 521 | } |
f11c88af | 522 | |
4db6e0b7 | 523 | static const struct rpc_call_ops nfs_read_common_ops = { |
f11c88af | 524 | .rpc_call_prepare = nfs_read_prepare, |
4db6e0b7 FI |
525 | .rpc_call_done = nfs_readpage_result_common, |
526 | .rpc_release = nfs_readpage_release_common, | |
ec06c096 TM |
527 | }; |
528 | ||
1da177e4 LT |
529 | /* |
530 | * Read a page over NFS. | |
531 | * We read the page synchronously in the following case: | |
532 | * - The error flag is set for this page. This happens only when a | |
533 | * previous async read operation failed. | |
534 | */ | |
535 | int nfs_readpage(struct file *file, struct page *page) | |
536 | { | |
537 | struct nfs_open_context *ctx; | |
538 | struct inode *inode = page->mapping->host; | |
539 | int error; | |
540 | ||
541 | dprintk("NFS: nfs_readpage (%p %ld@%lu)\n", | |
542 | page, PAGE_CACHE_SIZE, page->index); | |
91d5b470 CL |
543 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGE); |
544 | nfs_add_stats(inode, NFSIOS_READPAGES, 1); | |
545 | ||
1da177e4 LT |
546 | /* |
547 | * Try to flush any pending writes to the file.. | |
548 | * | |
549 | * NOTE! Because we own the page lock, there cannot | |
550 | * be any new pending writes generated at this point | |
551 | * for this page (other pages can be written to). | |
552 | */ | |
553 | error = nfs_wb_page(inode, page); | |
554 | if (error) | |
de05a0cc TM |
555 | goto out_unlock; |
556 | if (PageUptodate(page)) | |
557 | goto out_unlock; | |
1da177e4 | 558 | |
5f004cf2 TM |
559 | error = -ESTALE; |
560 | if (NFS_STALE(inode)) | |
de05a0cc | 561 | goto out_unlock; |
5f004cf2 | 562 | |
1da177e4 | 563 | if (file == NULL) { |
cf1308ff | 564 | error = -EBADF; |
d530838b | 565 | ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
1da177e4 | 566 | if (ctx == NULL) |
de05a0cc | 567 | goto out_unlock; |
1da177e4 | 568 | } else |
cd3758e3 | 569 | ctx = get_nfs_open_context(nfs_file_open_context(file)); |
1da177e4 | 570 | |
9a9fc1c0 DH |
571 | if (!IS_SYNC(inode)) { |
572 | error = nfs_readpage_from_fscache(ctx, inode, page); | |
573 | if (error == 0) | |
574 | goto out; | |
575 | } | |
576 | ||
8e0969f0 TM |
577 | error = nfs_readpage_async(ctx, inode, page); |
578 | ||
9a9fc1c0 | 579 | out: |
1da177e4 LT |
580 | put_nfs_open_context(ctx); |
581 | return error; | |
de05a0cc | 582 | out_unlock: |
1da177e4 LT |
583 | unlock_page(page); |
584 | return error; | |
585 | } | |
586 | ||
587 | struct nfs_readdesc { | |
8b09bee3 | 588 | struct nfs_pageio_descriptor *pgio; |
1da177e4 LT |
589 | struct nfs_open_context *ctx; |
590 | }; | |
591 | ||
592 | static int | |
593 | readpage_async_filler(void *data, struct page *page) | |
594 | { | |
595 | struct nfs_readdesc *desc = (struct nfs_readdesc *)data; | |
596 | struct inode *inode = page->mapping->host; | |
597 | struct nfs_page *new; | |
598 | unsigned int len; | |
de05a0cc TM |
599 | int error; |
600 | ||
49a70f27 | 601 | len = nfs_page_length(page); |
1da177e4 LT |
602 | if (len == 0) |
603 | return nfs_return_empty_page(page); | |
de05a0cc | 604 | |
1da177e4 | 605 | new = nfs_create_request(desc->ctx, inode, page, 0, len); |
de05a0cc TM |
606 | if (IS_ERR(new)) |
607 | goto out_error; | |
608 | ||
1da177e4 | 609 | if (len < PAGE_CACHE_SIZE) |
eebd2aa3 | 610 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
f8512ad0 FI |
611 | if (!nfs_pageio_add_request(desc->pgio, new)) { |
612 | error = desc->pgio->pg_error; | |
613 | goto out_unlock; | |
614 | } | |
1da177e4 | 615 | return 0; |
de05a0cc TM |
616 | out_error: |
617 | error = PTR_ERR(new); | |
de05a0cc TM |
618 | out_unlock: |
619 | unlock_page(page); | |
620 | return error; | |
1da177e4 LT |
621 | } |
622 | ||
623 | int nfs_readpages(struct file *filp, struct address_space *mapping, | |
624 | struct list_head *pages, unsigned nr_pages) | |
625 | { | |
8b09bee3 | 626 | struct nfs_pageio_descriptor pgio; |
1da177e4 | 627 | struct nfs_readdesc desc = { |
8b09bee3 | 628 | .pgio = &pgio, |
1da177e4 LT |
629 | }; |
630 | struct inode *inode = mapping->host; | |
8b09bee3 | 631 | unsigned long npages; |
5f004cf2 | 632 | int ret = -ESTALE; |
1da177e4 LT |
633 | |
634 | dprintk("NFS: nfs_readpages (%s/%Ld %d)\n", | |
635 | inode->i_sb->s_id, | |
636 | (long long)NFS_FILEID(inode), | |
637 | nr_pages); | |
91d5b470 | 638 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGES); |
1da177e4 | 639 | |
5f004cf2 TM |
640 | if (NFS_STALE(inode)) |
641 | goto out; | |
642 | ||
1da177e4 | 643 | if (filp == NULL) { |
d530838b | 644 | desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
1da177e4 LT |
645 | if (desc.ctx == NULL) |
646 | return -EBADF; | |
647 | } else | |
cd3758e3 | 648 | desc.ctx = get_nfs_open_context(nfs_file_open_context(filp)); |
9a9fc1c0 DH |
649 | |
650 | /* attempt to read as many of the pages as possible from the cache | |
651 | * - this returns -ENOBUFS immediately if the cookie is negative | |
652 | */ | |
653 | ret = nfs_readpages_from_fscache(desc.ctx, inode, mapping, | |
654 | pages, &nr_pages); | |
655 | if (ret == 0) | |
656 | goto read_complete; /* all pages were read */ | |
657 | ||
061ae2ed | 658 | nfs_pageio_init_read(&pgio, inode, &nfs_async_read_completion_ops); |
8b09bee3 | 659 | |
1da177e4 | 660 | ret = read_cache_pages(mapping, pages, readpage_async_filler, &desc); |
8b09bee3 TM |
661 | |
662 | nfs_pageio_complete(&pgio); | |
663 | npages = (pgio.pg_bytes_written + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; | |
664 | nfs_add_stats(inode, NFSIOS_READPAGES, npages); | |
9a9fc1c0 | 665 | read_complete: |
1da177e4 | 666 | put_nfs_open_context(desc.ctx); |
5f004cf2 | 667 | out: |
1da177e4 LT |
668 | return ret; |
669 | } | |
670 | ||
f7b422b1 | 671 | int __init nfs_init_readpagecache(void) |
1da177e4 LT |
672 | { |
673 | nfs_rdata_cachep = kmem_cache_create("nfs_read_data", | |
cd841605 | 674 | sizeof(struct nfs_read_header), |
1da177e4 | 675 | 0, SLAB_HWCACHE_ALIGN, |
20c2df83 | 676 | NULL); |
1da177e4 LT |
677 | if (nfs_rdata_cachep == NULL) |
678 | return -ENOMEM; | |
679 | ||
1da177e4 LT |
680 | return 0; |
681 | } | |
682 | ||
266bee88 | 683 | void nfs_destroy_readpagecache(void) |
1da177e4 | 684 | { |
1a1d92c1 | 685 | kmem_cache_destroy(nfs_rdata_cachep); |
1da177e4 | 686 | } |