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 | |
1385b811 | 38 | struct nfs_read_header *nfs_readhdr_alloc(void) |
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); |
2701d086 | 155 | NFS_I(inode)->read_io += pgio.pg_bytes_written; |
1da177e4 LT |
156 | return 0; |
157 | } | |
158 | ||
159 | static void nfs_readpage_release(struct nfs_page *req) | |
160 | { | |
3d4ff43d | 161 | struct inode *d_inode = req->wb_context->dentry->d_inode; |
7f8e05f6 DH |
162 | |
163 | if (PageUptodate(req->wb_page)) | |
164 | nfs_readpage_to_fscache(d_inode, req->wb_page, 0); | |
165 | ||
1da177e4 LT |
166 | unlock_page(req->wb_page); |
167 | ||
1da177e4 | 168 | dprintk("NFS: read done (%s/%Ld %d@%Ld)\n", |
3d4ff43d AV |
169 | req->wb_context->dentry->d_inode->i_sb->s_id, |
170 | (long long)NFS_FILEID(req->wb_context->dentry->d_inode), | |
1da177e4 LT |
171 | req->wb_bytes, |
172 | (long long)req_offset(req)); | |
10d2c46f | 173 | nfs_release_request(req); |
1da177e4 LT |
174 | } |
175 | ||
4db6e0b7 | 176 | /* Note io was page aligned */ |
061ae2ed | 177 | static void nfs_read_completion(struct nfs_pgio_header *hdr) |
4db6e0b7 FI |
178 | { |
179 | unsigned long bytes = 0; | |
180 | ||
181 | if (test_bit(NFS_IOHDR_REDO, &hdr->flags)) | |
182 | goto out; | |
4bd8b010 TM |
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); | |
4db6e0b7 | 194 | } |
4bd8b010 TM |
195 | bytes += req->wb_bytes; |
196 | if (test_bit(NFS_IOHDR_ERROR, &hdr->flags)) { | |
4db6e0b7 | 197 | if (bytes <= hdr->good_bytes) |
4bd8b010 TM |
198 | SetPageUptodate(page); |
199 | } else | |
200 | SetPageUptodate(page); | |
201 | nfs_list_remove_request(req); | |
202 | nfs_readpage_release(req); | |
4db6e0b7 FI |
203 | } |
204 | out: | |
205 | hdr->release(hdr); | |
206 | } | |
207 | ||
c5996c4e FI |
208 | int nfs_initiate_read(struct rpc_clnt *clnt, |
209 | struct nfs_read_data *data, | |
9f0ec176 | 210 | const struct rpc_call_ops *call_ops, int flags) |
1da177e4 | 211 | { |
cd841605 | 212 | struct inode *inode = data->header->inode; |
84115e1c | 213 | int swap_flags = IS_SWAPFILE(inode) ? NFS_RPC_SWAPFLAGS : 0; |
07737691 | 214 | struct rpc_task *task; |
bdc7f021 TM |
215 | struct rpc_message msg = { |
216 | .rpc_argp = &data->args, | |
217 | .rpc_resp = &data->res, | |
cd841605 | 218 | .rpc_cred = data->header->cred, |
bdc7f021 | 219 | }; |
84115e1c | 220 | struct rpc_task_setup task_setup_data = { |
07737691 | 221 | .task = &data->task, |
64419a9b | 222 | .rpc_client = clnt, |
bdc7f021 | 223 | .rpc_message = &msg, |
84115e1c TM |
224 | .callback_ops = call_ops, |
225 | .callback_data = data, | |
101070ca | 226 | .workqueue = nfsiod_workqueue, |
9f0ec176 | 227 | .flags = RPC_TASK_ASYNC | swap_flags | flags, |
84115e1c | 228 | }; |
1da177e4 | 229 | |
64419a9b AA |
230 | /* Set up the initial task struct. */ |
231 | NFS_PROTO(inode)->read_setup(data, &msg); | |
232 | ||
233 | dprintk("NFS: %5u initiated read call (req %s/%lld, %u bytes @ " | |
234 | "offset %llu)\n", | |
235 | data->task.tk_pid, | |
236 | inode->i_sb->s_id, | |
237 | (long long)NFS_FILEID(inode), | |
238 | data->args.count, | |
239 | (unsigned long long)data->args.offset); | |
240 | ||
241 | task = rpc_run_task(&task_setup_data); | |
242 | if (IS_ERR(task)) | |
243 | return PTR_ERR(task); | |
244 | rpc_put_task(task); | |
245 | return 0; | |
246 | } | |
dc70d7b3 | 247 | EXPORT_SYMBOL_GPL(nfs_initiate_read); |
64419a9b AA |
248 | |
249 | /* | |
250 | * Set up the NFS read request struct | |
251 | */ | |
4db6e0b7 | 252 | static void nfs_read_rpcsetup(struct nfs_read_data *data, |
6e4efd56 | 253 | unsigned int count, unsigned int offset) |
64419a9b | 254 | { |
4db6e0b7 | 255 | struct nfs_page *req = data->header->req; |
1da177e4 | 256 | |
4db6e0b7 | 257 | data->args.fh = NFS_FH(data->header->inode); |
1da177e4 LT |
258 | data->args.offset = req_offset(req) + offset; |
259 | data->args.pgbase = req->wb_pgbase + offset; | |
30dd374f | 260 | data->args.pages = data->pages.pagevec; |
1da177e4 | 261 | data->args.count = count; |
383ba719 | 262 | data->args.context = get_nfs_open_context(req->wb_context); |
f11ac8db | 263 | data->args.lock_context = req->wb_lock_context; |
1da177e4 LT |
264 | |
265 | data->res.fattr = &data->fattr; | |
266 | data->res.count = count; | |
267 | data->res.eof = 0; | |
0e574af1 | 268 | nfs_fattr_init(&data->fattr); |
6e4efd56 | 269 | } |
1da177e4 | 270 | |
6e4efd56 | 271 | static int nfs_do_read(struct nfs_read_data *data, |
493292dd | 272 | const struct rpc_call_ops *call_ops) |
6e4efd56 | 273 | { |
cd841605 | 274 | struct inode *inode = data->header->inode; |
6e4efd56 | 275 | |
9f0ec176 | 276 | return nfs_initiate_read(NFS_CLIENT(inode), data, call_ops, 0); |
1da177e4 LT |
277 | } |
278 | ||
275acaaf TM |
279 | static int |
280 | nfs_do_multiple_reads(struct list_head *head, | |
493292dd | 281 | const struct rpc_call_ops *call_ops) |
275acaaf TM |
282 | { |
283 | struct nfs_read_data *data; | |
284 | int ret = 0; | |
285 | ||
286 | while (!list_empty(head)) { | |
287 | int ret2; | |
288 | ||
4db6e0b7 | 289 | data = list_first_entry(head, struct nfs_read_data, list); |
275acaaf TM |
290 | list_del_init(&data->list); |
291 | ||
493292dd | 292 | ret2 = nfs_do_read(data, call_ops); |
275acaaf TM |
293 | if (ret == 0) |
294 | ret = ret2; | |
295 | } | |
296 | return ret; | |
297 | } | |
298 | ||
061ae2ed | 299 | static void |
1da177e4 LT |
300 | nfs_async_read_error(struct list_head *head) |
301 | { | |
302 | struct nfs_page *req; | |
303 | ||
304 | while (!list_empty(head)) { | |
305 | req = nfs_list_entry(head->next); | |
306 | nfs_list_remove_request(req); | |
1da177e4 LT |
307 | nfs_readpage_release(req); |
308 | } | |
309 | } | |
310 | ||
061ae2ed FI |
311 | static const struct nfs_pgio_completion_ops nfs_async_read_completion_ops = { |
312 | .error_cleanup = nfs_async_read_error, | |
313 | .completion = nfs_read_completion, | |
314 | }; | |
315 | ||
25b11dcd TM |
316 | static void nfs_pagein_error(struct nfs_pageio_descriptor *desc, |
317 | struct nfs_pgio_header *hdr) | |
318 | { | |
319 | set_bit(NFS_IOHDR_REDO, &hdr->flags); | |
320 | while (!list_empty(&hdr->rpc_list)) { | |
321 | struct nfs_read_data *data = list_first_entry(&hdr->rpc_list, | |
322 | struct nfs_read_data, list); | |
323 | list_del(&data->list); | |
324 | nfs_readdata_release(data); | |
325 | } | |
326 | desc->pg_completion_ops->error_cleanup(&desc->pg_list); | |
327 | } | |
328 | ||
1da177e4 LT |
329 | /* |
330 | * Generate multiple requests to fill a single page. | |
331 | * | |
332 | * We optimize to reduce the number of read operations on the wire. If we | |
333 | * detect that we're reading a page, or an area of a page, that is past the | |
334 | * end of file, we do not generate NFS read operations but just clear the | |
335 | * parts of the page that would have come back zero from the server anyway. | |
336 | * | |
337 | * We rely on the cached value of i_size to make this determination; another | |
338 | * client can fill pages on the server past our cached end-of-file, but we | |
339 | * won't see the new data until our attribute cache is updated. This is more | |
340 | * or less conventional NFS client behavior. | |
341 | */ | |
4db6e0b7 FI |
342 | static int nfs_pagein_multi(struct nfs_pageio_descriptor *desc, |
343 | struct nfs_pgio_header *hdr) | |
1da177e4 | 344 | { |
4db6e0b7 | 345 | struct nfs_page *req = hdr->req; |
1da177e4 LT |
346 | struct page *page = req->wb_page; |
347 | struct nfs_read_data *data; | |
d097971d | 348 | size_t rsize = desc->pg_bsize, nbytes; |
e9f7bee1 | 349 | unsigned int offset; |
1da177e4 | 350 | |
275acaaf | 351 | offset = 0; |
c76069bd | 352 | nbytes = desc->pg_count; |
e9f7bee1 TM |
353 | do { |
354 | size_t len = min(nbytes,rsize); | |
355 | ||
4db6e0b7 | 356 | data = nfs_readdata_alloc(hdr, 1); |
25b11dcd TM |
357 | if (!data) { |
358 | nfs_pagein_error(desc, hdr); | |
359 | return -ENOMEM; | |
360 | } | |
30dd374f | 361 | data->pages.pagevec[0] = page; |
4db6e0b7 FI |
362 | nfs_read_rpcsetup(data, len, offset); |
363 | list_add(&data->list, &hdr->rpc_list); | |
e9f7bee1 | 364 | nbytes -= len; |
275acaaf | 365 | offset += len; |
9146ab50 | 366 | } while (nbytes != 0); |
25b11dcd TM |
367 | |
368 | nfs_list_remove_request(req); | |
369 | nfs_list_add_request(req, &hdr->pages); | |
4db6e0b7 | 370 | desc->pg_rpc_callops = &nfs_read_common_ops; |
9146ab50 | 371 | return 0; |
1da177e4 LT |
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; |
1da177e4 | 381 | |
4db6e0b7 FI |
382 | data = nfs_readdata_alloc(hdr, nfs_page_array_len(desc->pg_base, |
383 | desc->pg_count)); | |
384 | if (!data) { | |
25b11dcd | 385 | nfs_pagein_error(desc, hdr); |
9146ab50 | 386 | return -ENOMEM; |
bae724ef | 387 | } |
1da177e4 | 388 | |
30dd374f | 389 | pages = data->pages.pagevec; |
1da177e4 LT |
390 | while (!list_empty(head)) { |
391 | req = nfs_list_entry(head->next); | |
392 | nfs_list_remove_request(req); | |
4db6e0b7 | 393 | nfs_list_add_request(req, &hdr->pages); |
1da177e4 | 394 | *pages++ = req->wb_page; |
1da177e4 | 395 | } |
1da177e4 | 396 | |
4db6e0b7 FI |
397 | nfs_read_rpcsetup(data, desc->pg_count, 0); |
398 | list_add(&data->list, &hdr->rpc_list); | |
399 | desc->pg_rpc_callops = &nfs_read_common_ops; | |
9146ab50 | 400 | return 0; |
1da177e4 LT |
401 | } |
402 | ||
4db6e0b7 FI |
403 | int nfs_generic_pagein(struct nfs_pageio_descriptor *desc, |
404 | struct nfs_pgio_header *hdr) | |
493292dd TM |
405 | { |
406 | if (desc->pg_bsize < PAGE_CACHE_SIZE) | |
4db6e0b7 FI |
407 | return nfs_pagein_multi(desc, hdr); |
408 | return nfs_pagein_one(desc, hdr); | |
493292dd TM |
409 | } |
410 | ||
411 | static int nfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc) | |
1751c363 | 412 | { |
4db6e0b7 FI |
413 | struct nfs_read_header *rhdr; |
414 | struct nfs_pgio_header *hdr; | |
275acaaf TM |
415 | int ret; |
416 | ||
4db6e0b7 FI |
417 | rhdr = nfs_readhdr_alloc(); |
418 | if (!rhdr) { | |
061ae2ed | 419 | desc->pg_completion_ops->error_cleanup(&desc->pg_list); |
4db6e0b7 FI |
420 | return -ENOMEM; |
421 | } | |
422 | hdr = &rhdr->header; | |
423 | nfs_pgheader_init(desc, hdr, nfs_readhdr_free); | |
424 | atomic_inc(&hdr->refcnt); | |
425 | ret = nfs_generic_pagein(desc, hdr); | |
50828d7e | 426 | if (ret == 0) |
4db6e0b7 FI |
427 | ret = nfs_do_multiple_reads(&hdr->rpc_list, |
428 | desc->pg_rpc_callops); | |
4db6e0b7 | 429 | if (atomic_dec_and_test(&hdr->refcnt)) |
061ae2ed | 430 | hdr->completion_ops->completion(hdr); |
275acaaf | 431 | return ret; |
1751c363 | 432 | } |
1751c363 TM |
433 | |
434 | static const struct nfs_pageio_ops nfs_pageio_read_ops = { | |
435 | .pg_test = nfs_generic_pg_test, | |
436 | .pg_doio = nfs_generic_pg_readpages, | |
437 | }; | |
438 | ||
0b671301 TM |
439 | /* |
440 | * This is the callback from RPC telling us whether a reply was | |
441 | * received or some error occurred (timeout or socket shutdown). | |
442 | */ | |
443 | int nfs_readpage_result(struct rpc_task *task, struct nfs_read_data *data) | |
444 | { | |
cd841605 | 445 | struct inode *inode = data->header->inode; |
0b671301 TM |
446 | int status; |
447 | ||
3110ff80 | 448 | dprintk("NFS: %s: %5u, (status %d)\n", __func__, task->tk_pid, |
0b671301 TM |
449 | task->tk_status); |
450 | ||
cd841605 | 451 | status = NFS_PROTO(inode)->read_done(task, data); |
0b671301 TM |
452 | if (status != 0) |
453 | return status; | |
454 | ||
cd841605 | 455 | nfs_add_stats(inode, NFSIOS_SERVERREADBYTES, data->res.count); |
0b671301 TM |
456 | |
457 | if (task->tk_status == -ESTALE) { | |
cd841605 FI |
458 | set_bit(NFS_INO_STALE, &NFS_I(inode)->flags); |
459 | nfs_mark_for_revalidate(inode); | |
0b671301 | 460 | } |
0b671301 TM |
461 | return 0; |
462 | } | |
463 | ||
fdd1e74c | 464 | static void nfs_readpage_retry(struct rpc_task *task, struct nfs_read_data *data) |
0b671301 TM |
465 | { |
466 | struct nfs_readargs *argp = &data->args; | |
467 | struct nfs_readres *resp = &data->res; | |
468 | ||
0b671301 | 469 | /* This is a short read! */ |
cd841605 | 470 | nfs_inc_stats(data->header->inode, NFSIOS_SHORTREAD); |
0b671301 | 471 | /* Has the server at least made some progress? */ |
4db6e0b7 FI |
472 | if (resp->count == 0) { |
473 | nfs_set_pgio_error(data->header, -EIO, argp->offset); | |
d61e612a | 474 | return; |
4db6e0b7 | 475 | } |
0b671301 | 476 | /* Yes, so retry the read at the end of the data */ |
cbdabc7f | 477 | data->mds_offset += resp->count; |
0b671301 TM |
478 | argp->offset += resp->count; |
479 | argp->pgbase += resp->count; | |
480 | argp->count -= resp->count; | |
d00c5d43 | 481 | rpc_restart_call_prepare(task); |
0b671301 TM |
482 | } |
483 | ||
4db6e0b7 | 484 | static void nfs_readpage_result_common(struct rpc_task *task, void *calldata) |
1da177e4 | 485 | { |
ec06c096 | 486 | struct nfs_read_data *data = calldata; |
4db6e0b7 FI |
487 | struct nfs_pgio_header *hdr = data->header; |
488 | ||
489 | /* Note the only returns of nfs_readpage_result are 0 and -EAGAIN */ | |
ec06c096 TM |
490 | if (nfs_readpage_result(task, data) != 0) |
491 | return; | |
fdd1e74c | 492 | if (task->tk_status < 0) |
4db6e0b7 FI |
493 | nfs_set_pgio_error(hdr, task->tk_status, data->args.offset); |
494 | else if (data->res.eof) { | |
495 | loff_t bound; | |
496 | ||
497 | bound = data->args.offset + data->res.count; | |
498 | spin_lock(&hdr->lock); | |
499 | if (bound < hdr->io_start + hdr->good_bytes) { | |
500 | set_bit(NFS_IOHDR_EOF, &hdr->flags); | |
501 | clear_bit(NFS_IOHDR_ERROR, &hdr->flags); | |
502 | hdr->good_bytes = bound - hdr->io_start; | |
503 | } | |
504 | spin_unlock(&hdr->lock); | |
505 | } else if (data->res.count != data->args.count) | |
506 | nfs_readpage_retry(task, data); | |
fdd1e74c TM |
507 | } |
508 | ||
4db6e0b7 | 509 | static void nfs_readpage_release_common(void *calldata) |
fdd1e74c | 510 | { |
4db6e0b7 | 511 | nfs_readdata_release(calldata); |
1da177e4 LT |
512 | } |
513 | ||
f11c88af AA |
514 | void nfs_read_prepare(struct rpc_task *task, void *calldata) |
515 | { | |
516 | struct nfs_read_data *data = calldata; | |
cd841605 | 517 | NFS_PROTO(data->header->inode)->read_rpc_prepare(task, data); |
f11c88af | 518 | } |
f11c88af | 519 | |
4db6e0b7 | 520 | static const struct rpc_call_ops nfs_read_common_ops = { |
f11c88af | 521 | .rpc_call_prepare = nfs_read_prepare, |
4db6e0b7 FI |
522 | .rpc_call_done = nfs_readpage_result_common, |
523 | .rpc_release = nfs_readpage_release_common, | |
ec06c096 TM |
524 | }; |
525 | ||
1da177e4 LT |
526 | /* |
527 | * Read a page over NFS. | |
528 | * We read the page synchronously in the following case: | |
529 | * - The error flag is set for this page. This happens only when a | |
530 | * previous async read operation failed. | |
531 | */ | |
532 | int nfs_readpage(struct file *file, struct page *page) | |
533 | { | |
534 | struct nfs_open_context *ctx; | |
535 | struct inode *inode = page->mapping->host; | |
536 | int error; | |
537 | ||
538 | dprintk("NFS: nfs_readpage (%p %ld@%lu)\n", | |
539 | page, PAGE_CACHE_SIZE, page->index); | |
91d5b470 CL |
540 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGE); |
541 | nfs_add_stats(inode, NFSIOS_READPAGES, 1); | |
542 | ||
1da177e4 LT |
543 | /* |
544 | * Try to flush any pending writes to the file.. | |
545 | * | |
546 | * NOTE! Because we own the page lock, there cannot | |
547 | * be any new pending writes generated at this point | |
548 | * for this page (other pages can be written to). | |
549 | */ | |
550 | error = nfs_wb_page(inode, page); | |
551 | if (error) | |
de05a0cc TM |
552 | goto out_unlock; |
553 | if (PageUptodate(page)) | |
554 | goto out_unlock; | |
1da177e4 | 555 | |
5f004cf2 TM |
556 | error = -ESTALE; |
557 | if (NFS_STALE(inode)) | |
de05a0cc | 558 | goto out_unlock; |
5f004cf2 | 559 | |
1da177e4 | 560 | if (file == NULL) { |
cf1308ff | 561 | error = -EBADF; |
d530838b | 562 | ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
1da177e4 | 563 | if (ctx == NULL) |
de05a0cc | 564 | goto out_unlock; |
1da177e4 | 565 | } else |
cd3758e3 | 566 | ctx = get_nfs_open_context(nfs_file_open_context(file)); |
1da177e4 | 567 | |
9a9fc1c0 DH |
568 | if (!IS_SYNC(inode)) { |
569 | error = nfs_readpage_from_fscache(ctx, inode, page); | |
570 | if (error == 0) | |
571 | goto out; | |
572 | } | |
573 | ||
8e0969f0 TM |
574 | error = nfs_readpage_async(ctx, inode, page); |
575 | ||
9a9fc1c0 | 576 | out: |
1da177e4 LT |
577 | put_nfs_open_context(ctx); |
578 | return error; | |
de05a0cc | 579 | out_unlock: |
1da177e4 LT |
580 | unlock_page(page); |
581 | return error; | |
582 | } | |
583 | ||
584 | struct nfs_readdesc { | |
8b09bee3 | 585 | struct nfs_pageio_descriptor *pgio; |
1da177e4 LT |
586 | struct nfs_open_context *ctx; |
587 | }; | |
588 | ||
589 | static int | |
590 | readpage_async_filler(void *data, struct page *page) | |
591 | { | |
592 | struct nfs_readdesc *desc = (struct nfs_readdesc *)data; | |
593 | struct inode *inode = page->mapping->host; | |
594 | struct nfs_page *new; | |
595 | unsigned int len; | |
de05a0cc TM |
596 | int error; |
597 | ||
49a70f27 | 598 | len = nfs_page_length(page); |
1da177e4 LT |
599 | if (len == 0) |
600 | return nfs_return_empty_page(page); | |
de05a0cc | 601 | |
1da177e4 | 602 | new = nfs_create_request(desc->ctx, inode, page, 0, len); |
de05a0cc TM |
603 | if (IS_ERR(new)) |
604 | goto out_error; | |
605 | ||
1da177e4 | 606 | if (len < PAGE_CACHE_SIZE) |
eebd2aa3 | 607 | zero_user_segment(page, len, PAGE_CACHE_SIZE); |
f8512ad0 FI |
608 | if (!nfs_pageio_add_request(desc->pgio, new)) { |
609 | error = desc->pgio->pg_error; | |
610 | goto out_unlock; | |
611 | } | |
1da177e4 | 612 | return 0; |
de05a0cc TM |
613 | out_error: |
614 | error = PTR_ERR(new); | |
de05a0cc TM |
615 | out_unlock: |
616 | unlock_page(page); | |
617 | return error; | |
1da177e4 LT |
618 | } |
619 | ||
620 | int nfs_readpages(struct file *filp, struct address_space *mapping, | |
621 | struct list_head *pages, unsigned nr_pages) | |
622 | { | |
8b09bee3 | 623 | struct nfs_pageio_descriptor pgio; |
1da177e4 | 624 | struct nfs_readdesc desc = { |
8b09bee3 | 625 | .pgio = &pgio, |
1da177e4 LT |
626 | }; |
627 | struct inode *inode = mapping->host; | |
8b09bee3 | 628 | unsigned long npages; |
5f004cf2 | 629 | int ret = -ESTALE; |
1da177e4 LT |
630 | |
631 | dprintk("NFS: nfs_readpages (%s/%Ld %d)\n", | |
632 | inode->i_sb->s_id, | |
633 | (long long)NFS_FILEID(inode), | |
634 | nr_pages); | |
91d5b470 | 635 | nfs_inc_stats(inode, NFSIOS_VFSREADPAGES); |
1da177e4 | 636 | |
5f004cf2 TM |
637 | if (NFS_STALE(inode)) |
638 | goto out; | |
639 | ||
1da177e4 | 640 | if (filp == NULL) { |
d530838b | 641 | desc.ctx = nfs_find_open_context(inode, NULL, FMODE_READ); |
1da177e4 LT |
642 | if (desc.ctx == NULL) |
643 | return -EBADF; | |
644 | } else | |
cd3758e3 | 645 | desc.ctx = get_nfs_open_context(nfs_file_open_context(filp)); |
9a9fc1c0 DH |
646 | |
647 | /* attempt to read as many of the pages as possible from the cache | |
648 | * - this returns -ENOBUFS immediately if the cookie is negative | |
649 | */ | |
650 | ret = nfs_readpages_from_fscache(desc.ctx, inode, mapping, | |
651 | pages, &nr_pages); | |
652 | if (ret == 0) | |
653 | goto read_complete; /* all pages were read */ | |
654 | ||
061ae2ed | 655 | nfs_pageio_init_read(&pgio, inode, &nfs_async_read_completion_ops); |
8b09bee3 | 656 | |
1da177e4 | 657 | ret = read_cache_pages(mapping, pages, readpage_async_filler, &desc); |
8b09bee3 TM |
658 | |
659 | nfs_pageio_complete(&pgio); | |
2701d086 | 660 | NFS_I(inode)->read_io += pgio.pg_bytes_written; |
8b09bee3 TM |
661 | npages = (pgio.pg_bytes_written + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; |
662 | nfs_add_stats(inode, NFSIOS_READPAGES, npages); | |
9a9fc1c0 | 663 | read_complete: |
1da177e4 | 664 | put_nfs_open_context(desc.ctx); |
5f004cf2 | 665 | out: |
1da177e4 LT |
666 | return ret; |
667 | } | |
668 | ||
f7b422b1 | 669 | int __init nfs_init_readpagecache(void) |
1da177e4 LT |
670 | { |
671 | nfs_rdata_cachep = kmem_cache_create("nfs_read_data", | |
cd841605 | 672 | sizeof(struct nfs_read_header), |
1da177e4 | 673 | 0, SLAB_HWCACHE_ALIGN, |
20c2df83 | 674 | NULL); |
1da177e4 LT |
675 | if (nfs_rdata_cachep == NULL) |
676 | return -ENOMEM; | |
677 | ||
1da177e4 LT |
678 | return 0; |
679 | } | |
680 | ||
266bee88 | 681 | void nfs_destroy_readpagecache(void) |
1da177e4 | 682 | { |
1a1d92c1 | 683 | kmem_cache_destroy(nfs_rdata_cachep); |
1da177e4 | 684 | } |