Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/nfs/direct.c | |
3 | * | |
4 | * Copyright (C) 2003 by Chuck Lever <cel@netapp.com> | |
5 | * | |
6 | * High-performance uncached I/O for the Linux NFS client | |
7 | * | |
8 | * There are important applications whose performance or correctness | |
9 | * depends on uncached access to file data. Database clusters | |
88467055 | 10 | * (multiple copies of the same instance running on separate hosts) |
1da177e4 | 11 | * implement their own cache coherency protocol that subsumes file |
88467055 CL |
12 | * system cache protocols. Applications that process datasets |
13 | * considerably larger than the client's memory do not always benefit | |
14 | * from a local cache. A streaming video server, for instance, has no | |
1da177e4 LT |
15 | * need to cache the contents of a file. |
16 | * | |
17 | * When an application requests uncached I/O, all read and write requests | |
18 | * are made directly to the server; data stored or fetched via these | |
19 | * requests is not cached in the Linux page cache. The client does not | |
20 | * correct unaligned requests from applications. All requested bytes are | |
21 | * held on permanent storage before a direct write system call returns to | |
22 | * an application. | |
23 | * | |
24 | * Solaris implements an uncached I/O facility called directio() that | |
25 | * is used for backups and sequential I/O to very large files. Solaris | |
26 | * also supports uncaching whole NFS partitions with "-o forcedirectio," | |
27 | * an undocumented mount option. | |
28 | * | |
29 | * Designed by Jeff Kimmel, Chuck Lever, and Trond Myklebust, with | |
30 | * help from Andrew Morton. | |
31 | * | |
32 | * 18 Dec 2001 Initial implementation for 2.4 --cel | |
33 | * 08 Jul 2002 Version for 2.4.19, with bug fixes --trondmy | |
34 | * 08 Jun 2003 Port to 2.5 APIs --cel | |
35 | * 31 Mar 2004 Handle direct I/O without VFS support --cel | |
36 | * 15 Sep 2004 Parallel async reads --cel | |
88467055 | 37 | * 04 May 2005 support O_DIRECT with aio --cel |
1da177e4 LT |
38 | * |
39 | */ | |
40 | ||
1da177e4 LT |
41 | #include <linux/errno.h> |
42 | #include <linux/sched.h> | |
43 | #include <linux/kernel.h> | |
1da177e4 LT |
44 | #include <linux/file.h> |
45 | #include <linux/pagemap.h> | |
46 | #include <linux/kref.h> | |
5a0e3ad6 | 47 | #include <linux/slab.h> |
7ec10f26 | 48 | #include <linux/task_io_accounting_ops.h> |
6296556f | 49 | #include <linux/module.h> |
1da177e4 LT |
50 | |
51 | #include <linux/nfs_fs.h> | |
52 | #include <linux/nfs_page.h> | |
53 | #include <linux/sunrpc/clnt.h> | |
54 | ||
1da177e4 | 55 | #include <asm/uaccess.h> |
60063497 | 56 | #include <linux/atomic.h> |
1da177e4 | 57 | |
8d5658c9 | 58 | #include "internal.h" |
91d5b470 | 59 | #include "iostat.h" |
1763da12 | 60 | #include "pnfs.h" |
91d5b470 | 61 | |
1da177e4 | 62 | #define NFSDBG_FACILITY NFSDBG_VFS |
1da177e4 | 63 | |
e18b890b | 64 | static struct kmem_cache *nfs_direct_cachep; |
1da177e4 LT |
65 | |
66 | /* | |
67 | * This represents a set of asynchronous requests that we're waiting on | |
68 | */ | |
69 | struct nfs_direct_req { | |
70 | struct kref kref; /* release manager */ | |
15ce4a0c CL |
71 | |
72 | /* I/O parameters */ | |
a8881f5a | 73 | struct nfs_open_context *ctx; /* file open context info */ |
f11ac8db | 74 | struct nfs_lock_context *l_ctx; /* Lock context info */ |
99514f8f | 75 | struct kiocb * iocb; /* controlling i/o request */ |
88467055 | 76 | struct inode * inode; /* target file of i/o */ |
15ce4a0c CL |
77 | |
78 | /* completion state */ | |
607f31e8 | 79 | atomic_t io_count; /* i/os we're waiting for */ |
15ce4a0c | 80 | spinlock_t lock; /* protect completion state */ |
15ce4a0c | 81 | ssize_t count, /* bytes actually processed */ |
35754bc0 | 82 | bytes_left, /* bytes left to be sent */ |
1da177e4 | 83 | error; /* any reported error */ |
d72b7a6b | 84 | struct completion completion; /* wait for i/o completion */ |
fad61490 TM |
85 | |
86 | /* commit state */ | |
1763da12 FI |
87 | struct nfs_mds_commit_info mds_cinfo; /* Storage for cinfo */ |
88 | struct pnfs_ds_commit_info ds_cinfo; /* Storage for cinfo */ | |
89 | struct work_struct work; | |
fad61490 TM |
90 | int flags; |
91 | #define NFS_ODIRECT_DO_COMMIT (1) /* an unstable reply was received */ | |
92 | #define NFS_ODIRECT_RESCHED_WRITES (2) /* write verification failed */ | |
93 | struct nfs_writeverf verf; /* unstable write verifier */ | |
1da177e4 LT |
94 | }; |
95 | ||
1763da12 FI |
96 | static const struct nfs_pgio_completion_ops nfs_direct_write_completion_ops; |
97 | static const struct nfs_commit_completion_ops nfs_direct_commit_completion_ops; | |
fad61490 | 98 | static void nfs_direct_write_complete(struct nfs_direct_req *dreq, struct inode *inode); |
1763da12 | 99 | static void nfs_direct_write_schedule_work(struct work_struct *work); |
607f31e8 TM |
100 | |
101 | static inline void get_dreq(struct nfs_direct_req *dreq) | |
102 | { | |
103 | atomic_inc(&dreq->io_count); | |
104 | } | |
105 | ||
106 | static inline int put_dreq(struct nfs_direct_req *dreq) | |
107 | { | |
108 | return atomic_dec_and_test(&dreq->io_count); | |
109 | } | |
110 | ||
5002c586 WAA |
111 | /* |
112 | * nfs_direct_select_verf - select the right verifier | |
113 | * @dreq - direct request possibly spanning multiple servers | |
114 | * @ds_clp - nfs_client of data server or NULL if MDS / non-pnfs | |
115 | * @ds_idx - index of data server in data server list, only valid if ds_clp set | |
116 | * | |
117 | * returns the correct verifier to use given the role of the server | |
118 | */ | |
119 | static struct nfs_writeverf * | |
120 | nfs_direct_select_verf(struct nfs_direct_req *dreq, | |
121 | struct nfs_client *ds_clp, | |
122 | int ds_idx) | |
123 | { | |
124 | struct nfs_writeverf *verfp = &dreq->verf; | |
125 | ||
126 | #ifdef CONFIG_NFS_V4_1 | |
127 | if (ds_clp) { | |
128 | /* pNFS is in use, use the DS verf */ | |
129 | if (ds_idx >= 0 && ds_idx < dreq->ds_cinfo.nbuckets) | |
130 | verfp = &dreq->ds_cinfo.buckets[ds_idx].direct_verf; | |
131 | else | |
132 | WARN_ON_ONCE(1); | |
133 | } | |
134 | #endif | |
135 | return verfp; | |
136 | } | |
137 | ||
138 | ||
139 | /* | |
140 | * nfs_direct_set_hdr_verf - set the write/commit verifier | |
141 | * @dreq - direct request possibly spanning multiple servers | |
142 | * @hdr - pageio header to validate against previously seen verfs | |
143 | * | |
144 | * Set the server's (MDS or DS) "seen" verifier | |
145 | */ | |
146 | static void nfs_direct_set_hdr_verf(struct nfs_direct_req *dreq, | |
147 | struct nfs_pgio_header *hdr) | |
148 | { | |
149 | struct nfs_writeverf *verfp; | |
150 | ||
d45f60c6 WAA |
151 | verfp = nfs_direct_select_verf(dreq, hdr->ds_clp, |
152 | hdr->ds_idx); | |
5002c586 WAA |
153 | WARN_ON_ONCE(verfp->committed >= 0); |
154 | memcpy(verfp, &hdr->verf, sizeof(struct nfs_writeverf)); | |
155 | WARN_ON_ONCE(verfp->committed < 0); | |
156 | } | |
157 | ||
158 | /* | |
159 | * nfs_direct_cmp_hdr_verf - compare verifier for pgio header | |
160 | * @dreq - direct request possibly spanning multiple servers | |
161 | * @hdr - pageio header to validate against previously seen verf | |
162 | * | |
163 | * set the server's "seen" verf if not initialized. | |
164 | * returns result of comparison between @hdr->verf and the "seen" | |
165 | * verf of the server used by @hdr (DS or MDS) | |
166 | */ | |
167 | static int nfs_direct_set_or_cmp_hdr_verf(struct nfs_direct_req *dreq, | |
168 | struct nfs_pgio_header *hdr) | |
169 | { | |
170 | struct nfs_writeverf *verfp; | |
171 | ||
d45f60c6 WAA |
172 | verfp = nfs_direct_select_verf(dreq, hdr->ds_clp, |
173 | hdr->ds_idx); | |
5002c586 WAA |
174 | if (verfp->committed < 0) { |
175 | nfs_direct_set_hdr_verf(dreq, hdr); | |
176 | return 0; | |
177 | } | |
178 | return memcmp(verfp, &hdr->verf, sizeof(struct nfs_writeverf)); | |
179 | } | |
180 | ||
5002c586 WAA |
181 | /* |
182 | * nfs_direct_cmp_commit_data_verf - compare verifier for commit data | |
183 | * @dreq - direct request possibly spanning multiple servers | |
184 | * @data - commit data to validate against previously seen verf | |
185 | * | |
186 | * returns result of comparison between @data->verf and the verf of | |
187 | * the server used by @data (DS or MDS) | |
188 | */ | |
189 | static int nfs_direct_cmp_commit_data_verf(struct nfs_direct_req *dreq, | |
190 | struct nfs_commit_data *data) | |
191 | { | |
192 | struct nfs_writeverf *verfp; | |
193 | ||
194 | verfp = nfs_direct_select_verf(dreq, data->ds_clp, | |
195 | data->ds_commit_index); | |
196 | WARN_ON_ONCE(verfp->committed < 0); | |
197 | return memcmp(verfp, &data->verf, sizeof(struct nfs_writeverf)); | |
198 | } | |
5002c586 | 199 | |
1da177e4 | 200 | /** |
b8a32e2b CL |
201 | * nfs_direct_IO - NFS address space operation for direct I/O |
202 | * @rw: direction (read or write) | |
203 | * @iocb: target I/O control block | |
204 | * @iov: array of vectors that define I/O buffer | |
205 | * @pos: offset in file to begin the operation | |
206 | * @nr_segs: size of iovec array | |
207 | * | |
208 | * The presence of this routine in the address space ops vector means | |
a564b8f0 MG |
209 | * the NFS client supports direct I/O. However, for most direct IO, we |
210 | * shunt off direct read and write requests before the VFS gets them, | |
211 | * so this method is only ever called for swap. | |
1da177e4 | 212 | */ |
d8d3d94b | 213 | ssize_t nfs_direct_IO(int rw, struct kiocb *iocb, struct iov_iter *iter, loff_t pos) |
b8a32e2b | 214 | { |
a564b8f0 | 215 | #ifndef CONFIG_NFS_SWAP |
6de1472f | 216 | dprintk("NFS: nfs_direct_IO (%pD) off/no(%Ld/%lu) EINVAL\n", |
d8d3d94b | 217 | iocb->ki_filp, (long long) pos, iter->nr_segs); |
b8a32e2b CL |
218 | |
219 | return -EINVAL; | |
a564b8f0 | 220 | #else |
a564b8f0 MG |
221 | VM_BUG_ON(iocb->ki_nbytes != PAGE_SIZE); |
222 | ||
e19a8a0a MP |
223 | if (rw == READ) |
224 | return nfs_file_direct_read(iocb, iter, pos); | |
225 | return nfs_file_direct_write(iocb, iter, pos); | |
a564b8f0 | 226 | #endif /* CONFIG_NFS_SWAP */ |
b8a32e2b CL |
227 | } |
228 | ||
749e146e | 229 | static void nfs_direct_release_pages(struct page **pages, unsigned int npages) |
9c93ab7d | 230 | { |
749e146e | 231 | unsigned int i; |
607f31e8 TM |
232 | for (i = 0; i < npages; i++) |
233 | page_cache_release(pages[i]); | |
6b45d858 TM |
234 | } |
235 | ||
1763da12 FI |
236 | void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo, |
237 | struct nfs_direct_req *dreq) | |
238 | { | |
239 | cinfo->lock = &dreq->lock; | |
240 | cinfo->mds = &dreq->mds_cinfo; | |
241 | cinfo->ds = &dreq->ds_cinfo; | |
242 | cinfo->dreq = dreq; | |
243 | cinfo->completion_ops = &nfs_direct_commit_completion_ops; | |
244 | } | |
245 | ||
93619e59 | 246 | static inline struct nfs_direct_req *nfs_direct_req_alloc(void) |
1da177e4 | 247 | { |
93619e59 CL |
248 | struct nfs_direct_req *dreq; |
249 | ||
292f3eee | 250 | dreq = kmem_cache_zalloc(nfs_direct_cachep, GFP_KERNEL); |
93619e59 CL |
251 | if (!dreq) |
252 | return NULL; | |
253 | ||
254 | kref_init(&dreq->kref); | |
607f31e8 | 255 | kref_get(&dreq->kref); |
d72b7a6b | 256 | init_completion(&dreq->completion); |
1763da12 | 257 | INIT_LIST_HEAD(&dreq->mds_cinfo.list); |
5002c586 | 258 | dreq->verf.committed = NFS_INVALID_STABLE_HOW; /* not set yet */ |
1763da12 | 259 | INIT_WORK(&dreq->work, nfs_direct_write_schedule_work); |
15ce4a0c | 260 | spin_lock_init(&dreq->lock); |
93619e59 CL |
261 | |
262 | return dreq; | |
1da177e4 LT |
263 | } |
264 | ||
b4946ffb | 265 | static void nfs_direct_req_free(struct kref *kref) |
1da177e4 LT |
266 | { |
267 | struct nfs_direct_req *dreq = container_of(kref, struct nfs_direct_req, kref); | |
a8881f5a | 268 | |
f11ac8db TM |
269 | if (dreq->l_ctx != NULL) |
270 | nfs_put_lock_context(dreq->l_ctx); | |
a8881f5a TM |
271 | if (dreq->ctx != NULL) |
272 | put_nfs_open_context(dreq->ctx); | |
1da177e4 LT |
273 | kmem_cache_free(nfs_direct_cachep, dreq); |
274 | } | |
275 | ||
b4946ffb TM |
276 | static void nfs_direct_req_release(struct nfs_direct_req *dreq) |
277 | { | |
278 | kref_put(&dreq->kref, nfs_direct_req_free); | |
279 | } | |
280 | ||
6296556f PT |
281 | ssize_t nfs_dreq_bytes_left(struct nfs_direct_req *dreq) |
282 | { | |
283 | return dreq->bytes_left; | |
284 | } | |
285 | EXPORT_SYMBOL_GPL(nfs_dreq_bytes_left); | |
286 | ||
bc0fb201 CL |
287 | /* |
288 | * Collects and returns the final error value/byte-count. | |
289 | */ | |
290 | static ssize_t nfs_direct_wait(struct nfs_direct_req *dreq) | |
291 | { | |
15ce4a0c | 292 | ssize_t result = -EIOCBQUEUED; |
bc0fb201 CL |
293 | |
294 | /* Async requests don't wait here */ | |
295 | if (dreq->iocb) | |
296 | goto out; | |
297 | ||
150030b7 | 298 | result = wait_for_completion_killable(&dreq->completion); |
bc0fb201 CL |
299 | |
300 | if (!result) | |
15ce4a0c | 301 | result = dreq->error; |
bc0fb201 | 302 | if (!result) |
15ce4a0c | 303 | result = dreq->count; |
bc0fb201 CL |
304 | |
305 | out: | |
bc0fb201 CL |
306 | return (ssize_t) result; |
307 | } | |
308 | ||
63ab46ab | 309 | /* |
607f31e8 TM |
310 | * Synchronous I/O uses a stack-allocated iocb. Thus we can't trust |
311 | * the iocb is still valid here if this is a synchronous request. | |
63ab46ab | 312 | */ |
9811cd57 | 313 | static void nfs_direct_complete(struct nfs_direct_req *dreq, bool write) |
63ab46ab | 314 | { |
9811cd57 CH |
315 | struct inode *inode = dreq->inode; |
316 | ||
2a009ec9 | 317 | if (dreq->iocb && write) { |
9811cd57 | 318 | loff_t pos = dreq->iocb->ki_pos + dreq->count; |
2a009ec9 CH |
319 | |
320 | spin_lock(&inode->i_lock); | |
321 | if (i_size_read(inode) < pos) | |
322 | i_size_write(inode, pos); | |
323 | spin_unlock(&inode->i_lock); | |
324 | } | |
325 | ||
1f90ee27 | 326 | if (write) |
2a009ec9 | 327 | nfs_zap_mapping(inode, inode->i_mapping); |
1f90ee27 CH |
328 | |
329 | inode_dio_done(inode); | |
2a009ec9 CH |
330 | |
331 | if (dreq->iocb) { | |
15ce4a0c | 332 | long res = (long) dreq->error; |
63ab46ab | 333 | if (!res) |
15ce4a0c | 334 | res = (long) dreq->count; |
63ab46ab | 335 | aio_complete(dreq->iocb, res, 0); |
d72b7a6b | 336 | } |
2a009ec9 | 337 | |
d72b7a6b | 338 | complete_all(&dreq->completion); |
63ab46ab | 339 | |
b4946ffb | 340 | nfs_direct_req_release(dreq); |
63ab46ab CL |
341 | } |
342 | ||
1385b811 | 343 | static void nfs_direct_readpage_release(struct nfs_page *req) |
1da177e4 | 344 | { |
1e8968c5 | 345 | dprintk("NFS: direct read done (%s/%llu %d@%lld)\n", |
584aa810 | 346 | req->wb_context->dentry->d_inode->i_sb->s_id, |
1e8968c5 | 347 | (unsigned long long)NFS_FILEID(req->wb_context->dentry->d_inode), |
584aa810 FI |
348 | req->wb_bytes, |
349 | (long long)req_offset(req)); | |
350 | nfs_release_request(req); | |
fdd1e74c TM |
351 | } |
352 | ||
584aa810 | 353 | static void nfs_direct_read_completion(struct nfs_pgio_header *hdr) |
fdd1e74c | 354 | { |
584aa810 FI |
355 | unsigned long bytes = 0; |
356 | struct nfs_direct_req *dreq = hdr->dreq; | |
fdd1e74c | 357 | |
584aa810 FI |
358 | if (test_bit(NFS_IOHDR_REDO, &hdr->flags)) |
359 | goto out_put; | |
15ce4a0c CL |
360 | |
361 | spin_lock(&dreq->lock); | |
584aa810 FI |
362 | if (test_bit(NFS_IOHDR_ERROR, &hdr->flags) && (hdr->good_bytes == 0)) |
363 | dreq->error = hdr->error; | |
364 | else | |
365 | dreq->count += hdr->good_bytes; | |
366 | spin_unlock(&dreq->lock); | |
367 | ||
4bd8b010 TM |
368 | while (!list_empty(&hdr->pages)) { |
369 | struct nfs_page *req = nfs_list_entry(hdr->pages.next); | |
370 | struct page *page = req->wb_page; | |
371 | ||
be7e9858 JL |
372 | if (!PageCompound(page) && bytes < hdr->good_bytes) |
373 | set_page_dirty(page); | |
4bd8b010 TM |
374 | bytes += req->wb_bytes; |
375 | nfs_list_remove_request(req); | |
376 | nfs_direct_readpage_release(req); | |
d4a8f367 | 377 | } |
584aa810 | 378 | out_put: |
607f31e8 | 379 | if (put_dreq(dreq)) |
9811cd57 | 380 | nfs_direct_complete(dreq, false); |
584aa810 | 381 | hdr->release(hdr); |
1da177e4 LT |
382 | } |
383 | ||
3e9e0ca3 | 384 | static void nfs_read_sync_pgio_error(struct list_head *head) |
cd841605 | 385 | { |
584aa810 | 386 | struct nfs_page *req; |
cd841605 | 387 | |
584aa810 FI |
388 | while (!list_empty(head)) { |
389 | req = nfs_list_entry(head->next); | |
390 | nfs_list_remove_request(req); | |
391 | nfs_release_request(req); | |
392 | } | |
cd841605 FI |
393 | } |
394 | ||
584aa810 FI |
395 | static void nfs_direct_pgio_init(struct nfs_pgio_header *hdr) |
396 | { | |
397 | get_dreq(hdr->dreq); | |
398 | } | |
399 | ||
400 | static const struct nfs_pgio_completion_ops nfs_direct_read_completion_ops = { | |
3e9e0ca3 | 401 | .error_cleanup = nfs_read_sync_pgio_error, |
584aa810 FI |
402 | .init_hdr = nfs_direct_pgio_init, |
403 | .completion = nfs_direct_read_completion, | |
404 | }; | |
405 | ||
d4cc948b | 406 | /* |
607f31e8 TM |
407 | * For each rsize'd chunk of the user's buffer, dispatch an NFS READ |
408 | * operation. If nfs_readdata_alloc() or get_user_pages() fails, | |
409 | * bail and stop sending more reads. Read length accounting is | |
410 | * handled automatically by nfs_direct_read_result(). Otherwise, if | |
411 | * no requests have been sent, just return an error. | |
1da177e4 | 412 | */ |
1da177e4 | 413 | |
91f79c43 AV |
414 | static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq, |
415 | struct iov_iter *iter, | |
416 | loff_t pos) | |
417 | { | |
418 | struct nfs_pageio_descriptor desc; | |
419 | struct inode *inode = dreq->inode; | |
420 | ssize_t result = -EINVAL; | |
421 | size_t requested_bytes = 0; | |
422 | size_t rsize = max_t(size_t, NFS_SERVER(inode)->rsize, PAGE_SIZE); | |
e9f7bee1 | 423 | |
16b90578 | 424 | nfs_pageio_init_read(&desc, dreq->inode, false, |
91f79c43 AV |
425 | &nfs_direct_read_completion_ops); |
426 | get_dreq(dreq); | |
427 | desc.pg_dreq = dreq; | |
428 | atomic_inc(&inode->i_dio_count); | |
a564b8f0 | 429 | |
91f79c43 AV |
430 | while (iov_iter_count(iter)) { |
431 | struct page **pagevec; | |
432 | size_t bytes; | |
433 | size_t pgbase; | |
434 | unsigned npages, i; | |
607f31e8 | 435 | |
91f79c43 AV |
436 | result = iov_iter_get_pages_alloc(iter, &pagevec, |
437 | rsize, &pgbase); | |
438 | if (result < 0) | |
439 | break; | |
440 | ||
441 | bytes = result; | |
442 | iov_iter_advance(iter, bytes); | |
443 | npages = (result + pgbase + PAGE_SIZE - 1) / PAGE_SIZE; | |
584aa810 FI |
444 | for (i = 0; i < npages; i++) { |
445 | struct nfs_page *req; | |
bf5fc402 | 446 | unsigned int req_len = min_t(size_t, bytes, PAGE_SIZE - pgbase); |
584aa810 | 447 | /* XXX do we need to do the eof zeroing found in async_filler? */ |
2bfc6e56 | 448 | req = nfs_create_request(dreq->ctx, pagevec[i], NULL, |
584aa810 FI |
449 | pgbase, req_len); |
450 | if (IS_ERR(req)) { | |
584aa810 FI |
451 | result = PTR_ERR(req); |
452 | break; | |
453 | } | |
454 | req->wb_index = pos >> PAGE_SHIFT; | |
455 | req->wb_offset = pos & ~PAGE_MASK; | |
91f79c43 AV |
456 | if (!nfs_pageio_add_request(&desc, req)) { |
457 | result = desc.pg_error; | |
584aa810 | 458 | nfs_release_request(req); |
584aa810 FI |
459 | break; |
460 | } | |
461 | pgbase = 0; | |
462 | bytes -= req_len; | |
91f79c43 | 463 | requested_bytes += req_len; |
584aa810 | 464 | pos += req_len; |
35754bc0 | 465 | dreq->bytes_left -= req_len; |
584aa810 | 466 | } |
6d74743b | 467 | nfs_direct_release_pages(pagevec, npages); |
91f79c43 | 468 | kvfree(pagevec); |
19f73787 CL |
469 | if (result < 0) |
470 | break; | |
19f73787 CL |
471 | } |
472 | ||
584aa810 FI |
473 | nfs_pageio_complete(&desc); |
474 | ||
839f7ad6 CL |
475 | /* |
476 | * If no bytes were started, return the error, and let the | |
477 | * generic layer handle the completion. | |
478 | */ | |
479 | if (requested_bytes == 0) { | |
1f90ee27 | 480 | inode_dio_done(inode); |
839f7ad6 CL |
481 | nfs_direct_req_release(dreq); |
482 | return result < 0 ? result : -EIO; | |
483 | } | |
484 | ||
19f73787 | 485 | if (put_dreq(dreq)) |
9811cd57 | 486 | nfs_direct_complete(dreq, false); |
839f7ad6 | 487 | return 0; |
19f73787 CL |
488 | } |
489 | ||
14a3ec79 CH |
490 | /** |
491 | * nfs_file_direct_read - file direct read operation for NFS files | |
492 | * @iocb: target I/O control block | |
619d30b4 | 493 | * @iter: vector of user buffers into which to read data |
14a3ec79 CH |
494 | * @pos: byte offset in file where reading starts |
495 | * | |
496 | * We use this function for direct reads instead of calling | |
497 | * generic_file_aio_read() in order to avoid gfar's check to see if | |
498 | * the request starts before the end of the file. For that check | |
499 | * to work, we must generate a GETATTR before each direct read, and | |
500 | * even then there is a window between the GETATTR and the subsequent | |
501 | * READ where the file size could change. Our preference is simply | |
502 | * to do all reads the application wants, and the server will take | |
503 | * care of managing the end of file boundary. | |
504 | * | |
505 | * This function also eliminates unnecessarily updating the file's | |
506 | * atime locally, as the NFS server sets the file's atime, and this | |
507 | * client must read the updated atime from the server back into its | |
508 | * cache. | |
509 | */ | |
619d30b4 | 510 | ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter, |
e19a8a0a | 511 | loff_t pos) |
1da177e4 | 512 | { |
14a3ec79 CH |
513 | struct file *file = iocb->ki_filp; |
514 | struct address_space *mapping = file->f_mapping; | |
515 | struct inode *inode = mapping->host; | |
1da177e4 | 516 | struct nfs_direct_req *dreq; |
b3c54de6 | 517 | struct nfs_lock_context *l_ctx; |
14a3ec79 | 518 | ssize_t result = -EINVAL; |
a6cbcd4a | 519 | size_t count = iov_iter_count(iter); |
14a3ec79 CH |
520 | nfs_add_stats(mapping->host, NFSIOS_DIRECTREADBYTES, count); |
521 | ||
522 | dfprintk(FILE, "NFS: direct read(%pD2, %zd@%Ld)\n", | |
523 | file, count, (long long) pos); | |
524 | ||
525 | result = 0; | |
526 | if (!count) | |
527 | goto out; | |
528 | ||
d0b9875d | 529 | mutex_lock(&inode->i_mutex); |
14a3ec79 CH |
530 | result = nfs_sync_mapping(mapping); |
531 | if (result) | |
d0b9875d | 532 | goto out_unlock; |
1da177e4 | 533 | |
14a3ec79 CH |
534 | task_io_account_read(count); |
535 | ||
536 | result = -ENOMEM; | |
607f31e8 | 537 | dreq = nfs_direct_req_alloc(); |
f11ac8db | 538 | if (dreq == NULL) |
d0b9875d | 539 | goto out_unlock; |
1da177e4 | 540 | |
91d5b470 | 541 | dreq->inode = inode; |
619d30b4 | 542 | dreq->bytes_left = count; |
cd3758e3 | 543 | dreq->ctx = get_nfs_open_context(nfs_file_open_context(iocb->ki_filp)); |
b3c54de6 TM |
544 | l_ctx = nfs_get_lock_context(dreq->ctx); |
545 | if (IS_ERR(l_ctx)) { | |
546 | result = PTR_ERR(l_ctx); | |
f11ac8db | 547 | goto out_release; |
b3c54de6 TM |
548 | } |
549 | dreq->l_ctx = l_ctx; | |
487b8372 CL |
550 | if (!is_sync_kiocb(iocb)) |
551 | dreq->iocb = iocb; | |
1da177e4 | 552 | |
619d30b4 | 553 | NFS_I(inode)->read_io += count; |
91f79c43 | 554 | result = nfs_direct_read_schedule_iovec(dreq, iter, pos); |
d0b9875d CH |
555 | |
556 | mutex_unlock(&inode->i_mutex); | |
557 | ||
14a3ec79 | 558 | if (!result) { |
607f31e8 | 559 | result = nfs_direct_wait(dreq); |
14a3ec79 CH |
560 | if (result > 0) |
561 | iocb->ki_pos = pos + result; | |
562 | } | |
d0b9875d CH |
563 | |
564 | nfs_direct_req_release(dreq); | |
565 | return result; | |
566 | ||
f11ac8db | 567 | out_release: |
b4946ffb | 568 | nfs_direct_req_release(dreq); |
d0b9875d CH |
569 | out_unlock: |
570 | mutex_unlock(&inode->i_mutex); | |
f11ac8db | 571 | out: |
1da177e4 LT |
572 | return result; |
573 | } | |
574 | ||
fad61490 TM |
575 | static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq) |
576 | { | |
1763da12 FI |
577 | struct nfs_pageio_descriptor desc; |
578 | struct nfs_page *req, *tmp; | |
579 | LIST_HEAD(reqs); | |
580 | struct nfs_commit_info cinfo; | |
581 | LIST_HEAD(failed); | |
582 | ||
583 | nfs_init_cinfo_from_dreq(&cinfo, dreq); | |
584 | pnfs_recover_commit_reqs(dreq->inode, &reqs, &cinfo); | |
585 | spin_lock(cinfo.lock); | |
586 | nfs_scan_commit_list(&cinfo.mds->list, &reqs, &cinfo, 0); | |
587 | spin_unlock(cinfo.lock); | |
1da177e4 | 588 | |
fad61490 | 589 | dreq->count = 0; |
607f31e8 TM |
590 | get_dreq(dreq); |
591 | ||
a20c93e3 | 592 | nfs_pageio_init_write(&desc, dreq->inode, FLUSH_STABLE, false, |
1763da12 FI |
593 | &nfs_direct_write_completion_ops); |
594 | desc.pg_dreq = dreq; | |
fedb595c | 595 | |
1763da12 FI |
596 | list_for_each_entry_safe(req, tmp, &reqs, wb_list) { |
597 | if (!nfs_pageio_add_request(&desc, req)) { | |
4035c248 | 598 | nfs_list_remove_request(req); |
1763da12 FI |
599 | nfs_list_add_request(req, &failed); |
600 | spin_lock(cinfo.lock); | |
601 | dreq->flags = 0; | |
602 | dreq->error = -EIO; | |
603 | spin_unlock(cinfo.lock); | |
604 | } | |
5a695da2 | 605 | nfs_release_request(req); |
1763da12 FI |
606 | } |
607 | nfs_pageio_complete(&desc); | |
fad61490 | 608 | |
4035c248 TM |
609 | while (!list_empty(&failed)) { |
610 | req = nfs_list_entry(failed.next); | |
611 | nfs_list_remove_request(req); | |
1d1afcbc | 612 | nfs_unlock_and_release_request(req); |
4035c248 | 613 | } |
fad61490 | 614 | |
1763da12 FI |
615 | if (put_dreq(dreq)) |
616 | nfs_direct_write_complete(dreq, dreq->inode); | |
c9d8f89d TM |
617 | } |
618 | ||
1763da12 | 619 | static void nfs_direct_commit_complete(struct nfs_commit_data *data) |
c9d8f89d | 620 | { |
0b7c0153 | 621 | struct nfs_direct_req *dreq = data->dreq; |
1763da12 FI |
622 | struct nfs_commit_info cinfo; |
623 | struct nfs_page *req; | |
c9d8f89d TM |
624 | int status = data->task.tk_status; |
625 | ||
1763da12 | 626 | nfs_init_cinfo_from_dreq(&cinfo, dreq); |
c9d8f89d | 627 | if (status < 0) { |
60fa3f76 | 628 | dprintk("NFS: %5u commit failed with error %d.\n", |
1763da12 | 629 | data->task.tk_pid, status); |
fad61490 | 630 | dreq->flags = NFS_ODIRECT_RESCHED_WRITES; |
5002c586 | 631 | } else if (nfs_direct_cmp_commit_data_verf(dreq, data)) { |
c9d8f89d | 632 | dprintk("NFS: %5u commit verify failed\n", data->task.tk_pid); |
fad61490 | 633 | dreq->flags = NFS_ODIRECT_RESCHED_WRITES; |
1da177e4 LT |
634 | } |
635 | ||
c9d8f89d | 636 | dprintk("NFS: %5u commit returned %d\n", data->task.tk_pid, status); |
1763da12 FI |
637 | while (!list_empty(&data->pages)) { |
638 | req = nfs_list_entry(data->pages.next); | |
639 | nfs_list_remove_request(req); | |
640 | if (dreq->flags == NFS_ODIRECT_RESCHED_WRITES) { | |
641 | /* Note the rewrite will go through mds */ | |
642 | nfs_mark_request_commit(req, NULL, &cinfo); | |
906369e4 FI |
643 | } else |
644 | nfs_release_request(req); | |
1d1afcbc | 645 | nfs_unlock_and_release_request(req); |
1763da12 FI |
646 | } |
647 | ||
648 | if (atomic_dec_and_test(&cinfo.mds->rpcs_out)) | |
649 | nfs_direct_write_complete(dreq, data->inode); | |
1da177e4 LT |
650 | } |
651 | ||
1763da12 FI |
652 | static void nfs_direct_error_cleanup(struct nfs_inode *nfsi) |
653 | { | |
654 | /* There is no lock to clear */ | |
655 | } | |
656 | ||
657 | static const struct nfs_commit_completion_ops nfs_direct_commit_completion_ops = { | |
658 | .completion = nfs_direct_commit_complete, | |
659 | .error_cleanup = nfs_direct_error_cleanup, | |
fad61490 TM |
660 | }; |
661 | ||
662 | static void nfs_direct_commit_schedule(struct nfs_direct_req *dreq) | |
1da177e4 | 663 | { |
1763da12 FI |
664 | int res; |
665 | struct nfs_commit_info cinfo; | |
666 | LIST_HEAD(mds_list); | |
667 | ||
668 | nfs_init_cinfo_from_dreq(&cinfo, dreq); | |
669 | nfs_scan_commit(dreq->inode, &mds_list, &cinfo); | |
670 | res = nfs_generic_commit_list(dreq->inode, &mds_list, 0, &cinfo); | |
671 | if (res < 0) /* res == -ENOMEM */ | |
672 | nfs_direct_write_reschedule(dreq); | |
fad61490 | 673 | } |
1da177e4 | 674 | |
1763da12 | 675 | static void nfs_direct_write_schedule_work(struct work_struct *work) |
fad61490 | 676 | { |
1763da12 | 677 | struct nfs_direct_req *dreq = container_of(work, struct nfs_direct_req, work); |
fad61490 | 678 | int flags = dreq->flags; |
1da177e4 | 679 | |
fad61490 TM |
680 | dreq->flags = 0; |
681 | switch (flags) { | |
682 | case NFS_ODIRECT_DO_COMMIT: | |
683 | nfs_direct_commit_schedule(dreq); | |
1da177e4 | 684 | break; |
fad61490 TM |
685 | case NFS_ODIRECT_RESCHED_WRITES: |
686 | nfs_direct_write_reschedule(dreq); | |
687 | break; | |
688 | default: | |
9811cd57 | 689 | nfs_direct_complete(dreq, true); |
fad61490 TM |
690 | } |
691 | } | |
1da177e4 | 692 | |
1763da12 | 693 | static void nfs_direct_write_complete(struct nfs_direct_req *dreq, struct inode *inode) |
fad61490 | 694 | { |
1763da12 | 695 | schedule_work(&dreq->work); /* Calls nfs_direct_write_schedule_work */ |
fad61490 | 696 | } |
1763da12 | 697 | |
1763da12 FI |
698 | static void nfs_direct_write_completion(struct nfs_pgio_header *hdr) |
699 | { | |
700 | struct nfs_direct_req *dreq = hdr->dreq; | |
701 | struct nfs_commit_info cinfo; | |
c65e6254 | 702 | bool request_commit = false; |
1763da12 FI |
703 | struct nfs_page *req = nfs_list_entry(hdr->pages.next); |
704 | ||
705 | if (test_bit(NFS_IOHDR_REDO, &hdr->flags)) | |
706 | goto out_put; | |
707 | ||
708 | nfs_init_cinfo_from_dreq(&cinfo, dreq); | |
709 | ||
710 | spin_lock(&dreq->lock); | |
711 | ||
712 | if (test_bit(NFS_IOHDR_ERROR, &hdr->flags)) { | |
713 | dreq->flags = 0; | |
714 | dreq->error = hdr->error; | |
715 | } | |
c65e6254 | 716 | if (dreq->error == 0) { |
1763da12 | 717 | dreq->count += hdr->good_bytes; |
c65e6254 | 718 | if (nfs_write_need_commit(hdr)) { |
1763da12 | 719 | if (dreq->flags == NFS_ODIRECT_RESCHED_WRITES) |
c65e6254 | 720 | request_commit = true; |
1763da12 | 721 | else if (dreq->flags == 0) { |
5002c586 | 722 | nfs_direct_set_hdr_verf(dreq, hdr); |
c65e6254 | 723 | request_commit = true; |
1763da12 FI |
724 | dreq->flags = NFS_ODIRECT_DO_COMMIT; |
725 | } else if (dreq->flags == NFS_ODIRECT_DO_COMMIT) { | |
c65e6254 WAA |
726 | request_commit = true; |
727 | if (nfs_direct_set_or_cmp_hdr_verf(dreq, hdr)) | |
5002c586 WAA |
728 | dreq->flags = |
729 | NFS_ODIRECT_RESCHED_WRITES; | |
1763da12 FI |
730 | } |
731 | } | |
732 | } | |
733 | spin_unlock(&dreq->lock); | |
734 | ||
735 | while (!list_empty(&hdr->pages)) { | |
2bfc6e56 | 736 | |
1763da12 FI |
737 | req = nfs_list_entry(hdr->pages.next); |
738 | nfs_list_remove_request(req); | |
c65e6254 | 739 | if (request_commit) { |
04277086 | 740 | kref_get(&req->wb_kref); |
1763da12 | 741 | nfs_mark_request_commit(req, hdr->lseg, &cinfo); |
1763da12 | 742 | } |
1d1afcbc | 743 | nfs_unlock_and_release_request(req); |
1763da12 FI |
744 | } |
745 | ||
746 | out_put: | |
747 | if (put_dreq(dreq)) | |
748 | nfs_direct_write_complete(dreq, hdr->inode); | |
749 | hdr->release(hdr); | |
750 | } | |
751 | ||
3e9e0ca3 TM |
752 | static void nfs_write_sync_pgio_error(struct list_head *head) |
753 | { | |
754 | struct nfs_page *req; | |
755 | ||
756 | while (!list_empty(head)) { | |
757 | req = nfs_list_entry(head->next); | |
758 | nfs_list_remove_request(req); | |
1d1afcbc | 759 | nfs_unlock_and_release_request(req); |
3e9e0ca3 TM |
760 | } |
761 | } | |
762 | ||
1763da12 | 763 | static const struct nfs_pgio_completion_ops nfs_direct_write_completion_ops = { |
3e9e0ca3 | 764 | .error_cleanup = nfs_write_sync_pgio_error, |
1763da12 FI |
765 | .init_hdr = nfs_direct_pgio_init, |
766 | .completion = nfs_direct_write_completion, | |
767 | }; | |
768 | ||
91f79c43 AV |
769 | |
770 | /* | |
771 | * NB: Return the value of the first error return code. Subsequent | |
772 | * errors after the first one are ignored. | |
773 | */ | |
774 | /* | |
775 | * For each wsize'd chunk of the user's buffer, dispatch an NFS WRITE | |
776 | * operation. If nfs_writedata_alloc() or get_user_pages() fails, | |
777 | * bail and stop sending more writes. Write length accounting is | |
778 | * handled automatically by nfs_direct_write_result(). Otherwise, if | |
779 | * no requests have been sent, just return an error. | |
780 | */ | |
19f73787 | 781 | static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq, |
619d30b4 | 782 | struct iov_iter *iter, |
91f79c43 | 783 | loff_t pos) |
19f73787 | 784 | { |
1763da12 | 785 | struct nfs_pageio_descriptor desc; |
1d59d61f | 786 | struct inode *inode = dreq->inode; |
19f73787 CL |
787 | ssize_t result = 0; |
788 | size_t requested_bytes = 0; | |
91f79c43 | 789 | size_t wsize = max_t(size_t, NFS_SERVER(inode)->wsize, PAGE_SIZE); |
19f73787 | 790 | |
a20c93e3 | 791 | nfs_pageio_init_write(&desc, inode, FLUSH_COND_STABLE, false, |
1763da12 FI |
792 | &nfs_direct_write_completion_ops); |
793 | desc.pg_dreq = dreq; | |
19f73787 | 794 | get_dreq(dreq); |
1d59d61f | 795 | atomic_inc(&inode->i_dio_count); |
19f73787 | 796 | |
91f79c43 AV |
797 | NFS_I(inode)->write_io += iov_iter_count(iter); |
798 | while (iov_iter_count(iter)) { | |
799 | struct page **pagevec; | |
800 | size_t bytes; | |
801 | size_t pgbase; | |
802 | unsigned npages, i; | |
803 | ||
804 | result = iov_iter_get_pages_alloc(iter, &pagevec, | |
805 | wsize, &pgbase); | |
19f73787 CL |
806 | if (result < 0) |
807 | break; | |
91f79c43 AV |
808 | |
809 | bytes = result; | |
810 | iov_iter_advance(iter, bytes); | |
811 | npages = (result + pgbase + PAGE_SIZE - 1) / PAGE_SIZE; | |
812 | for (i = 0; i < npages; i++) { | |
813 | struct nfs_page *req; | |
814 | unsigned int req_len = min_t(size_t, bytes, PAGE_SIZE - pgbase); | |
815 | ||
16b90578 | 816 | req = nfs_create_request(dreq->ctx, pagevec[i], NULL, |
91f79c43 AV |
817 | pgbase, req_len); |
818 | if (IS_ERR(req)) { | |
819 | result = PTR_ERR(req); | |
820 | break; | |
821 | } | |
822 | nfs_lock_request(req); | |
823 | req->wb_index = pos >> PAGE_SHIFT; | |
824 | req->wb_offset = pos & ~PAGE_MASK; | |
825 | if (!nfs_pageio_add_request(&desc, req)) { | |
826 | result = desc.pg_error; | |
827 | nfs_unlock_and_release_request(req); | |
828 | break; | |
829 | } | |
830 | pgbase = 0; | |
831 | bytes -= req_len; | |
832 | requested_bytes += req_len; | |
833 | pos += req_len; | |
834 | dreq->bytes_left -= req_len; | |
835 | } | |
836 | nfs_direct_release_pages(pagevec, npages); | |
837 | kvfree(pagevec); | |
838 | if (result < 0) | |
19f73787 | 839 | break; |
19f73787 | 840 | } |
1763da12 | 841 | nfs_pageio_complete(&desc); |
19f73787 | 842 | |
839f7ad6 CL |
843 | /* |
844 | * If no bytes were started, return the error, and let the | |
845 | * generic layer handle the completion. | |
846 | */ | |
847 | if (requested_bytes == 0) { | |
1d59d61f | 848 | inode_dio_done(inode); |
839f7ad6 CL |
849 | nfs_direct_req_release(dreq); |
850 | return result < 0 ? result : -EIO; | |
851 | } | |
852 | ||
19f73787 CL |
853 | if (put_dreq(dreq)) |
854 | nfs_direct_write_complete(dreq, dreq->inode); | |
839f7ad6 | 855 | return 0; |
19f73787 CL |
856 | } |
857 | ||
1da177e4 LT |
858 | /** |
859 | * nfs_file_direct_write - file direct write operation for NFS files | |
860 | * @iocb: target I/O control block | |
619d30b4 | 861 | * @iter: vector of user buffers from which to write data |
88467055 | 862 | * @pos: byte offset in file where writing starts |
1da177e4 LT |
863 | * |
864 | * We use this function for direct writes instead of calling | |
865 | * generic_file_aio_write() in order to avoid taking the inode | |
866 | * semaphore and updating the i_size. The NFS server will set | |
867 | * the new i_size and this client must read the updated size | |
868 | * back into its cache. We let the server do generic write | |
869 | * parameter checking and report problems. | |
870 | * | |
1da177e4 LT |
871 | * We eliminate local atime updates, see direct read above. |
872 | * | |
873 | * We avoid unnecessary page cache invalidations for normal cached | |
874 | * readers of this file. | |
875 | * | |
876 | * Note that O_APPEND is not supported for NFS direct writes, as there | |
877 | * is no atomic O_APPEND write facility in the NFS protocol. | |
878 | */ | |
619d30b4 | 879 | ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter, |
e19a8a0a | 880 | loff_t pos) |
1da177e4 | 881 | { |
22cd1bf1 | 882 | ssize_t result = -EINVAL; |
1da177e4 | 883 | struct file *file = iocb->ki_filp; |
1da177e4 | 884 | struct address_space *mapping = file->f_mapping; |
22cd1bf1 CH |
885 | struct inode *inode = mapping->host; |
886 | struct nfs_direct_req *dreq; | |
887 | struct nfs_lock_context *l_ctx; | |
a9ab5e84 | 888 | loff_t end; |
a6cbcd4a | 889 | size_t count = iov_iter_count(iter); |
a9ab5e84 CH |
890 | end = (pos + count - 1) >> PAGE_CACHE_SHIFT; |
891 | ||
c216fd70 CL |
892 | nfs_add_stats(mapping->host, NFSIOS_DIRECTWRITTENBYTES, count); |
893 | ||
6de1472f AV |
894 | dfprintk(FILE, "NFS: direct write(%pD2, %zd@%Ld)\n", |
895 | file, count, (long long) pos); | |
027445c3 | 896 | |
22cd1bf1 CH |
897 | result = generic_write_checks(file, &pos, &count, 0); |
898 | if (result) | |
1da177e4 | 899 | goto out; |
ce1a8e67 | 900 | |
22cd1bf1 | 901 | result = -EINVAL; |
ce1a8e67 | 902 | if ((ssize_t) count < 0) |
1da177e4 | 903 | goto out; |
22cd1bf1 | 904 | result = 0; |
1da177e4 LT |
905 | if (!count) |
906 | goto out; | |
ce1a8e67 | 907 | |
a9ab5e84 CH |
908 | mutex_lock(&inode->i_mutex); |
909 | ||
22cd1bf1 CH |
910 | result = nfs_sync_mapping(mapping); |
911 | if (result) | |
a9ab5e84 CH |
912 | goto out_unlock; |
913 | ||
914 | if (mapping->nrpages) { | |
915 | result = invalidate_inode_pages2_range(mapping, | |
916 | pos >> PAGE_CACHE_SHIFT, end); | |
917 | if (result) | |
918 | goto out_unlock; | |
919 | } | |
1da177e4 | 920 | |
7ec10f26 KK |
921 | task_io_account_write(count); |
922 | ||
22cd1bf1 CH |
923 | result = -ENOMEM; |
924 | dreq = nfs_direct_req_alloc(); | |
925 | if (!dreq) | |
a9ab5e84 | 926 | goto out_unlock; |
9eafa8cc | 927 | |
22cd1bf1 CH |
928 | dreq->inode = inode; |
929 | dreq->bytes_left = count; | |
930 | dreq->ctx = get_nfs_open_context(nfs_file_open_context(iocb->ki_filp)); | |
931 | l_ctx = nfs_get_lock_context(dreq->ctx); | |
932 | if (IS_ERR(l_ctx)) { | |
933 | result = PTR_ERR(l_ctx); | |
934 | goto out_release; | |
935 | } | |
936 | dreq->l_ctx = l_ctx; | |
937 | if (!is_sync_kiocb(iocb)) | |
938 | dreq->iocb = iocb; | |
939 | ||
91f79c43 | 940 | result = nfs_direct_write_schedule_iovec(dreq, iter, pos); |
a9ab5e84 CH |
941 | |
942 | if (mapping->nrpages) { | |
943 | invalidate_inode_pages2_range(mapping, | |
944 | pos >> PAGE_CACHE_SHIFT, end); | |
945 | } | |
946 | ||
947 | mutex_unlock(&inode->i_mutex); | |
948 | ||
22cd1bf1 CH |
949 | if (!result) { |
950 | result = nfs_direct_wait(dreq); | |
951 | if (result > 0) { | |
952 | struct inode *inode = mapping->host; | |
953 | ||
954 | iocb->ki_pos = pos + result; | |
955 | spin_lock(&inode->i_lock); | |
956 | if (i_size_read(inode) < iocb->ki_pos) | |
957 | i_size_write(inode, iocb->ki_pos); | |
958 | spin_unlock(&inode->i_lock); | |
959 | } | |
1763da12 | 960 | } |
a9ab5e84 CH |
961 | nfs_direct_req_release(dreq); |
962 | return result; | |
963 | ||
22cd1bf1 CH |
964 | out_release: |
965 | nfs_direct_req_release(dreq); | |
a9ab5e84 CH |
966 | out_unlock: |
967 | mutex_unlock(&inode->i_mutex); | |
1da177e4 | 968 | out: |
22cd1bf1 | 969 | return result; |
1da177e4 LT |
970 | } |
971 | ||
88467055 CL |
972 | /** |
973 | * nfs_init_directcache - create a slab cache for nfs_direct_req structures | |
974 | * | |
975 | */ | |
f7b422b1 | 976 | int __init nfs_init_directcache(void) |
1da177e4 LT |
977 | { |
978 | nfs_direct_cachep = kmem_cache_create("nfs_direct_cache", | |
979 | sizeof(struct nfs_direct_req), | |
fffb60f9 PJ |
980 | 0, (SLAB_RECLAIM_ACCOUNT| |
981 | SLAB_MEM_SPREAD), | |
20c2df83 | 982 | NULL); |
1da177e4 LT |
983 | if (nfs_direct_cachep == NULL) |
984 | return -ENOMEM; | |
985 | ||
986 | return 0; | |
987 | } | |
988 | ||
88467055 | 989 | /** |
f7b422b1 | 990 | * nfs_destroy_directcache - destroy the slab cache for nfs_direct_req structures |
88467055 CL |
991 | * |
992 | */ | |
266bee88 | 993 | void nfs_destroy_directcache(void) |
1da177e4 | 994 | { |
1a1d92c1 | 995 | kmem_cache_destroy(nfs_direct_cachep); |
1da177e4 | 996 | } |