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 | */ | |
0a00b77b WAA |
69 | struct nfs_direct_mirror { |
70 | ssize_t count; | |
71 | }; | |
72 | ||
1da177e4 LT |
73 | struct nfs_direct_req { |
74 | struct kref kref; /* release manager */ | |
15ce4a0c CL |
75 | |
76 | /* I/O parameters */ | |
a8881f5a | 77 | struct nfs_open_context *ctx; /* file open context info */ |
f11ac8db | 78 | struct nfs_lock_context *l_ctx; /* Lock context info */ |
99514f8f | 79 | struct kiocb * iocb; /* controlling i/o request */ |
88467055 | 80 | struct inode * inode; /* target file of i/o */ |
15ce4a0c CL |
81 | |
82 | /* completion state */ | |
607f31e8 | 83 | atomic_t io_count; /* i/os we're waiting for */ |
15ce4a0c | 84 | spinlock_t lock; /* protect completion state */ |
0a00b77b WAA |
85 | |
86 | struct nfs_direct_mirror mirrors[NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX]; | |
87 | int mirror_count; | |
88 | ||
15ce4a0c | 89 | ssize_t count, /* bytes actually processed */ |
ed3743a6 | 90 | max_count, /* max expected count */ |
35754bc0 | 91 | bytes_left, /* bytes left to be sent */ |
5fadeb47 | 92 | io_start, /* start of IO */ |
1da177e4 | 93 | error; /* any reported error */ |
d72b7a6b | 94 | struct completion completion; /* wait for i/o completion */ |
fad61490 TM |
95 | |
96 | /* commit state */ | |
1763da12 FI |
97 | struct nfs_mds_commit_info mds_cinfo; /* Storage for cinfo */ |
98 | struct pnfs_ds_commit_info ds_cinfo; /* Storage for cinfo */ | |
99 | struct work_struct work; | |
fad61490 TM |
100 | int flags; |
101 | #define NFS_ODIRECT_DO_COMMIT (1) /* an unstable reply was received */ | |
102 | #define NFS_ODIRECT_RESCHED_WRITES (2) /* write verification failed */ | |
103 | struct nfs_writeverf verf; /* unstable write verifier */ | |
1da177e4 LT |
104 | }; |
105 | ||
1763da12 FI |
106 | static const struct nfs_pgio_completion_ops nfs_direct_write_completion_ops; |
107 | static const struct nfs_commit_completion_ops nfs_direct_commit_completion_ops; | |
fad61490 | 108 | static void nfs_direct_write_complete(struct nfs_direct_req *dreq, struct inode *inode); |
1763da12 | 109 | static void nfs_direct_write_schedule_work(struct work_struct *work); |
607f31e8 TM |
110 | |
111 | static inline void get_dreq(struct nfs_direct_req *dreq) | |
112 | { | |
113 | atomic_inc(&dreq->io_count); | |
114 | } | |
115 | ||
116 | static inline int put_dreq(struct nfs_direct_req *dreq) | |
117 | { | |
118 | return atomic_dec_and_test(&dreq->io_count); | |
119 | } | |
120 | ||
0a00b77b WAA |
121 | static void |
122 | nfs_direct_good_bytes(struct nfs_direct_req *dreq, struct nfs_pgio_header *hdr) | |
123 | { | |
124 | int i; | |
125 | ssize_t count; | |
126 | ||
ed3743a6 WAA |
127 | WARN_ON_ONCE(dreq->count >= dreq->max_count); |
128 | ||
1ccbad9f PT |
129 | if (dreq->mirror_count == 1) { |
130 | dreq->mirrors[hdr->pgio_mirror_idx].count += hdr->good_bytes; | |
131 | dreq->count += hdr->good_bytes; | |
132 | } else { | |
133 | /* mirrored writes */ | |
134 | count = dreq->mirrors[hdr->pgio_mirror_idx].count; | |
135 | if (count + dreq->io_start < hdr->io_start + hdr->good_bytes) { | |
136 | count = hdr->io_start + hdr->good_bytes - dreq->io_start; | |
137 | dreq->mirrors[hdr->pgio_mirror_idx].count = count; | |
138 | } | |
139 | /* update the dreq->count by finding the minimum agreed count from all | |
140 | * mirrors */ | |
141 | count = dreq->mirrors[0].count; | |
0a00b77b | 142 | |
1ccbad9f PT |
143 | for (i = 1; i < dreq->mirror_count; i++) |
144 | count = min(count, dreq->mirrors[i].count); | |
0a00b77b | 145 | |
1ccbad9f | 146 | dreq->count = count; |
5fadeb47 | 147 | } |
0a00b77b WAA |
148 | } |
149 | ||
5002c586 WAA |
150 | /* |
151 | * nfs_direct_select_verf - select the right verifier | |
152 | * @dreq - direct request possibly spanning multiple servers | |
153 | * @ds_clp - nfs_client of data server or NULL if MDS / non-pnfs | |
6cccbb6f | 154 | * @commit_idx - commit bucket index for the DS |
5002c586 WAA |
155 | * |
156 | * returns the correct verifier to use given the role of the server | |
157 | */ | |
158 | static struct nfs_writeverf * | |
159 | nfs_direct_select_verf(struct nfs_direct_req *dreq, | |
160 | struct nfs_client *ds_clp, | |
6cccbb6f | 161 | int commit_idx) |
5002c586 WAA |
162 | { |
163 | struct nfs_writeverf *verfp = &dreq->verf; | |
164 | ||
165 | #ifdef CONFIG_NFS_V4_1 | |
834e465b KM |
166 | /* |
167 | * pNFS is in use, use the DS verf except commit_through_mds is set | |
168 | * for layout segment where nbuckets is zero. | |
169 | */ | |
170 | if (ds_clp && dreq->ds_cinfo.nbuckets > 0) { | |
6cccbb6f WAA |
171 | if (commit_idx >= 0 && commit_idx < dreq->ds_cinfo.nbuckets) |
172 | verfp = &dreq->ds_cinfo.buckets[commit_idx].direct_verf; | |
5002c586 WAA |
173 | else |
174 | WARN_ON_ONCE(1); | |
175 | } | |
176 | #endif | |
177 | return verfp; | |
178 | } | |
179 | ||
180 | ||
181 | /* | |
182 | * nfs_direct_set_hdr_verf - set the write/commit verifier | |
183 | * @dreq - direct request possibly spanning multiple servers | |
184 | * @hdr - pageio header to validate against previously seen verfs | |
185 | * | |
186 | * Set the server's (MDS or DS) "seen" verifier | |
187 | */ | |
188 | static void nfs_direct_set_hdr_verf(struct nfs_direct_req *dreq, | |
189 | struct nfs_pgio_header *hdr) | |
190 | { | |
191 | struct nfs_writeverf *verfp; | |
192 | ||
6cccbb6f | 193 | verfp = nfs_direct_select_verf(dreq, hdr->ds_clp, hdr->ds_commit_idx); |
5002c586 WAA |
194 | WARN_ON_ONCE(verfp->committed >= 0); |
195 | memcpy(verfp, &hdr->verf, sizeof(struct nfs_writeverf)); | |
196 | WARN_ON_ONCE(verfp->committed < 0); | |
197 | } | |
198 | ||
8fc3c386 TM |
199 | static int nfs_direct_cmp_verf(const struct nfs_writeverf *v1, |
200 | const struct nfs_writeverf *v2) | |
201 | { | |
202 | return nfs_write_verifier_cmp(&v1->verifier, &v2->verifier); | |
203 | } | |
204 | ||
5002c586 WAA |
205 | /* |
206 | * nfs_direct_cmp_hdr_verf - compare verifier for pgio header | |
207 | * @dreq - direct request possibly spanning multiple servers | |
208 | * @hdr - pageio header to validate against previously seen verf | |
209 | * | |
210 | * set the server's "seen" verf if not initialized. | |
211 | * returns result of comparison between @hdr->verf and the "seen" | |
212 | * verf of the server used by @hdr (DS or MDS) | |
213 | */ | |
214 | static int nfs_direct_set_or_cmp_hdr_verf(struct nfs_direct_req *dreq, | |
215 | struct nfs_pgio_header *hdr) | |
216 | { | |
217 | struct nfs_writeverf *verfp; | |
218 | ||
6cccbb6f | 219 | verfp = nfs_direct_select_verf(dreq, hdr->ds_clp, hdr->ds_commit_idx); |
5002c586 WAA |
220 | if (verfp->committed < 0) { |
221 | nfs_direct_set_hdr_verf(dreq, hdr); | |
222 | return 0; | |
223 | } | |
8fc3c386 | 224 | return nfs_direct_cmp_verf(verfp, &hdr->verf); |
5002c586 WAA |
225 | } |
226 | ||
5002c586 WAA |
227 | /* |
228 | * nfs_direct_cmp_commit_data_verf - compare verifier for commit data | |
229 | * @dreq - direct request possibly spanning multiple servers | |
230 | * @data - commit data to validate against previously seen verf | |
231 | * | |
232 | * returns result of comparison between @data->verf and the verf of | |
233 | * the server used by @data (DS or MDS) | |
234 | */ | |
235 | static int nfs_direct_cmp_commit_data_verf(struct nfs_direct_req *dreq, | |
236 | struct nfs_commit_data *data) | |
237 | { | |
238 | struct nfs_writeverf *verfp; | |
239 | ||
240 | verfp = nfs_direct_select_verf(dreq, data->ds_clp, | |
241 | data->ds_commit_index); | |
80c76fe3 WAA |
242 | |
243 | /* verifier not set so always fail */ | |
244 | if (verfp->committed < 0) | |
245 | return 1; | |
246 | ||
8fc3c386 | 247 | return nfs_direct_cmp_verf(verfp, &data->verf); |
5002c586 | 248 | } |
5002c586 | 249 | |
1da177e4 | 250 | /** |
b8a32e2b | 251 | * nfs_direct_IO - NFS address space operation for direct I/O |
b8a32e2b CL |
252 | * @iocb: target I/O control block |
253 | * @iov: array of vectors that define I/O buffer | |
254 | * @pos: offset in file to begin the operation | |
255 | * @nr_segs: size of iovec array | |
256 | * | |
257 | * The presence of this routine in the address space ops vector means | |
a564b8f0 MG |
258 | * the NFS client supports direct I/O. However, for most direct IO, we |
259 | * shunt off direct read and write requests before the VFS gets them, | |
260 | * so this method is only ever called for swap. | |
1da177e4 | 261 | */ |
c8b8e32d | 262 | ssize_t nfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) |
b8a32e2b | 263 | { |
ee8a1a8b PT |
264 | struct inode *inode = iocb->ki_filp->f_mapping->host; |
265 | ||
266 | /* we only support swap file calling nfs_direct_IO */ | |
267 | if (!IS_SWAPFILE(inode)) | |
268 | return 0; | |
269 | ||
66ee59af | 270 | VM_BUG_ON(iov_iter_count(iter) != PAGE_SIZE); |
a564b8f0 | 271 | |
6f673763 | 272 | if (iov_iter_rw(iter) == READ) |
c8b8e32d | 273 | return nfs_file_direct_read(iocb, iter); |
65a4a1ca | 274 | return nfs_file_direct_write(iocb, iter); |
b8a32e2b CL |
275 | } |
276 | ||
749e146e | 277 | static void nfs_direct_release_pages(struct page **pages, unsigned int npages) |
9c93ab7d | 278 | { |
749e146e | 279 | unsigned int i; |
607f31e8 | 280 | for (i = 0; i < npages; i++) |
09cbfeaf | 281 | put_page(pages[i]); |
6b45d858 TM |
282 | } |
283 | ||
1763da12 FI |
284 | void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo, |
285 | struct nfs_direct_req *dreq) | |
286 | { | |
fe238e60 | 287 | cinfo->inode = dreq->inode; |
1763da12 FI |
288 | cinfo->mds = &dreq->mds_cinfo; |
289 | cinfo->ds = &dreq->ds_cinfo; | |
290 | cinfo->dreq = dreq; | |
291 | cinfo->completion_ops = &nfs_direct_commit_completion_ops; | |
292 | } | |
293 | ||
0a00b77b WAA |
294 | static inline void nfs_direct_setup_mirroring(struct nfs_direct_req *dreq, |
295 | struct nfs_pageio_descriptor *pgio, | |
296 | struct nfs_page *req) | |
297 | { | |
298 | int mirror_count = 1; | |
299 | ||
300 | if (pgio->pg_ops->pg_get_mirror_count) | |
301 | mirror_count = pgio->pg_ops->pg_get_mirror_count(pgio, req); | |
302 | ||
303 | dreq->mirror_count = mirror_count; | |
304 | } | |
305 | ||
93619e59 | 306 | static inline struct nfs_direct_req *nfs_direct_req_alloc(void) |
1da177e4 | 307 | { |
93619e59 CL |
308 | struct nfs_direct_req *dreq; |
309 | ||
292f3eee | 310 | dreq = kmem_cache_zalloc(nfs_direct_cachep, GFP_KERNEL); |
93619e59 CL |
311 | if (!dreq) |
312 | return NULL; | |
313 | ||
314 | kref_init(&dreq->kref); | |
607f31e8 | 315 | kref_get(&dreq->kref); |
d72b7a6b | 316 | init_completion(&dreq->completion); |
1763da12 | 317 | INIT_LIST_HEAD(&dreq->mds_cinfo.list); |
5002c586 | 318 | dreq->verf.committed = NFS_INVALID_STABLE_HOW; /* not set yet */ |
1763da12 | 319 | INIT_WORK(&dreq->work, nfs_direct_write_schedule_work); |
0a00b77b | 320 | dreq->mirror_count = 1; |
15ce4a0c | 321 | spin_lock_init(&dreq->lock); |
93619e59 CL |
322 | |
323 | return dreq; | |
1da177e4 LT |
324 | } |
325 | ||
b4946ffb | 326 | static void nfs_direct_req_free(struct kref *kref) |
1da177e4 LT |
327 | { |
328 | struct nfs_direct_req *dreq = container_of(kref, struct nfs_direct_req, kref); | |
a8881f5a | 329 | |
8c393f9a | 330 | nfs_free_pnfs_ds_cinfo(&dreq->ds_cinfo); |
f11ac8db TM |
331 | if (dreq->l_ctx != NULL) |
332 | nfs_put_lock_context(dreq->l_ctx); | |
a8881f5a TM |
333 | if (dreq->ctx != NULL) |
334 | put_nfs_open_context(dreq->ctx); | |
1da177e4 LT |
335 | kmem_cache_free(nfs_direct_cachep, dreq); |
336 | } | |
337 | ||
b4946ffb TM |
338 | static void nfs_direct_req_release(struct nfs_direct_req *dreq) |
339 | { | |
340 | kref_put(&dreq->kref, nfs_direct_req_free); | |
341 | } | |
342 | ||
6296556f PT |
343 | ssize_t nfs_dreq_bytes_left(struct nfs_direct_req *dreq) |
344 | { | |
345 | return dreq->bytes_left; | |
346 | } | |
347 | EXPORT_SYMBOL_GPL(nfs_dreq_bytes_left); | |
348 | ||
bc0fb201 CL |
349 | /* |
350 | * Collects and returns the final error value/byte-count. | |
351 | */ | |
352 | static ssize_t nfs_direct_wait(struct nfs_direct_req *dreq) | |
353 | { | |
15ce4a0c | 354 | ssize_t result = -EIOCBQUEUED; |
bc0fb201 CL |
355 | |
356 | /* Async requests don't wait here */ | |
357 | if (dreq->iocb) | |
358 | goto out; | |
359 | ||
150030b7 | 360 | result = wait_for_completion_killable(&dreq->completion); |
bc0fb201 CL |
361 | |
362 | if (!result) | |
15ce4a0c | 363 | result = dreq->error; |
bc0fb201 | 364 | if (!result) |
15ce4a0c | 365 | result = dreq->count; |
bc0fb201 CL |
366 | |
367 | out: | |
bc0fb201 CL |
368 | return (ssize_t) result; |
369 | } | |
370 | ||
63ab46ab | 371 | /* |
607f31e8 TM |
372 | * Synchronous I/O uses a stack-allocated iocb. Thus we can't trust |
373 | * the iocb is still valid here if this is a synchronous request. | |
63ab46ab | 374 | */ |
9811cd57 | 375 | static void nfs_direct_complete(struct nfs_direct_req *dreq, bool write) |
63ab46ab | 376 | { |
9811cd57 CH |
377 | struct inode *inode = dreq->inode; |
378 | ||
2a009ec9 | 379 | if (dreq->iocb && write) { |
9811cd57 | 380 | loff_t pos = dreq->iocb->ki_pos + dreq->count; |
2a009ec9 CH |
381 | |
382 | spin_lock(&inode->i_lock); | |
383 | if (i_size_read(inode) < pos) | |
384 | i_size_write(inode, pos); | |
385 | spin_unlock(&inode->i_lock); | |
386 | } | |
387 | ||
1f90ee27 | 388 | if (write) |
2a009ec9 | 389 | nfs_zap_mapping(inode, inode->i_mapping); |
1f90ee27 | 390 | |
fe0f07d0 | 391 | inode_dio_end(inode); |
2a009ec9 CH |
392 | |
393 | if (dreq->iocb) { | |
15ce4a0c | 394 | long res = (long) dreq->error; |
63ab46ab | 395 | if (!res) |
15ce4a0c | 396 | res = (long) dreq->count; |
04b2fa9f | 397 | dreq->iocb->ki_complete(dreq->iocb, res, 0); |
d72b7a6b | 398 | } |
2a009ec9 | 399 | |
d72b7a6b | 400 | complete_all(&dreq->completion); |
63ab46ab | 401 | |
b4946ffb | 402 | nfs_direct_req_release(dreq); |
63ab46ab CL |
403 | } |
404 | ||
1385b811 | 405 | static void nfs_direct_readpage_release(struct nfs_page *req) |
1da177e4 | 406 | { |
1e8968c5 | 407 | dprintk("NFS: direct read done (%s/%llu %d@%lld)\n", |
fc64005c | 408 | req->wb_context->dentry->d_sb->s_id, |
2b0143b5 | 409 | (unsigned long long)NFS_FILEID(d_inode(req->wb_context->dentry)), |
584aa810 FI |
410 | req->wb_bytes, |
411 | (long long)req_offset(req)); | |
412 | nfs_release_request(req); | |
fdd1e74c TM |
413 | } |
414 | ||
584aa810 | 415 | static void nfs_direct_read_completion(struct nfs_pgio_header *hdr) |
fdd1e74c | 416 | { |
584aa810 FI |
417 | unsigned long bytes = 0; |
418 | struct nfs_direct_req *dreq = hdr->dreq; | |
fdd1e74c | 419 | |
584aa810 FI |
420 | if (test_bit(NFS_IOHDR_REDO, &hdr->flags)) |
421 | goto out_put; | |
15ce4a0c CL |
422 | |
423 | spin_lock(&dreq->lock); | |
584aa810 FI |
424 | if (test_bit(NFS_IOHDR_ERROR, &hdr->flags) && (hdr->good_bytes == 0)) |
425 | dreq->error = hdr->error; | |
426 | else | |
0a00b77b WAA |
427 | nfs_direct_good_bytes(dreq, hdr); |
428 | ||
584aa810 FI |
429 | spin_unlock(&dreq->lock); |
430 | ||
4bd8b010 TM |
431 | while (!list_empty(&hdr->pages)) { |
432 | struct nfs_page *req = nfs_list_entry(hdr->pages.next); | |
433 | struct page *page = req->wb_page; | |
434 | ||
be7e9858 JL |
435 | if (!PageCompound(page) && bytes < hdr->good_bytes) |
436 | set_page_dirty(page); | |
4bd8b010 TM |
437 | bytes += req->wb_bytes; |
438 | nfs_list_remove_request(req); | |
439 | nfs_direct_readpage_release(req); | |
d4a8f367 | 440 | } |
584aa810 | 441 | out_put: |
607f31e8 | 442 | if (put_dreq(dreq)) |
9811cd57 | 443 | nfs_direct_complete(dreq, false); |
584aa810 | 444 | hdr->release(hdr); |
1da177e4 LT |
445 | } |
446 | ||
3e9e0ca3 | 447 | static void nfs_read_sync_pgio_error(struct list_head *head) |
cd841605 | 448 | { |
584aa810 | 449 | struct nfs_page *req; |
cd841605 | 450 | |
584aa810 FI |
451 | while (!list_empty(head)) { |
452 | req = nfs_list_entry(head->next); | |
453 | nfs_list_remove_request(req); | |
454 | nfs_release_request(req); | |
455 | } | |
cd841605 FI |
456 | } |
457 | ||
584aa810 FI |
458 | static void nfs_direct_pgio_init(struct nfs_pgio_header *hdr) |
459 | { | |
460 | get_dreq(hdr->dreq); | |
461 | } | |
462 | ||
463 | static const struct nfs_pgio_completion_ops nfs_direct_read_completion_ops = { | |
3e9e0ca3 | 464 | .error_cleanup = nfs_read_sync_pgio_error, |
584aa810 FI |
465 | .init_hdr = nfs_direct_pgio_init, |
466 | .completion = nfs_direct_read_completion, | |
467 | }; | |
468 | ||
d4cc948b | 469 | /* |
607f31e8 TM |
470 | * For each rsize'd chunk of the user's buffer, dispatch an NFS READ |
471 | * operation. If nfs_readdata_alloc() or get_user_pages() fails, | |
472 | * bail and stop sending more reads. Read length accounting is | |
473 | * handled automatically by nfs_direct_read_result(). Otherwise, if | |
474 | * no requests have been sent, just return an error. | |
1da177e4 | 475 | */ |
1da177e4 | 476 | |
91f79c43 AV |
477 | static ssize_t nfs_direct_read_schedule_iovec(struct nfs_direct_req *dreq, |
478 | struct iov_iter *iter, | |
479 | loff_t pos) | |
480 | { | |
481 | struct nfs_pageio_descriptor desc; | |
482 | struct inode *inode = dreq->inode; | |
483 | ssize_t result = -EINVAL; | |
484 | size_t requested_bytes = 0; | |
485 | size_t rsize = max_t(size_t, NFS_SERVER(inode)->rsize, PAGE_SIZE); | |
e9f7bee1 | 486 | |
16b90578 | 487 | nfs_pageio_init_read(&desc, dreq->inode, false, |
91f79c43 AV |
488 | &nfs_direct_read_completion_ops); |
489 | get_dreq(dreq); | |
490 | desc.pg_dreq = dreq; | |
fe0f07d0 | 491 | inode_dio_begin(inode); |
a564b8f0 | 492 | |
91f79c43 AV |
493 | while (iov_iter_count(iter)) { |
494 | struct page **pagevec; | |
495 | size_t bytes; | |
496 | size_t pgbase; | |
497 | unsigned npages, i; | |
607f31e8 | 498 | |
91f79c43 AV |
499 | result = iov_iter_get_pages_alloc(iter, &pagevec, |
500 | rsize, &pgbase); | |
501 | if (result < 0) | |
502 | break; | |
503 | ||
504 | bytes = result; | |
505 | iov_iter_advance(iter, bytes); | |
506 | npages = (result + pgbase + PAGE_SIZE - 1) / PAGE_SIZE; | |
584aa810 FI |
507 | for (i = 0; i < npages; i++) { |
508 | struct nfs_page *req; | |
bf5fc402 | 509 | unsigned int req_len = min_t(size_t, bytes, PAGE_SIZE - pgbase); |
584aa810 | 510 | /* XXX do we need to do the eof zeroing found in async_filler? */ |
2bfc6e56 | 511 | req = nfs_create_request(dreq->ctx, pagevec[i], NULL, |
584aa810 FI |
512 | pgbase, req_len); |
513 | if (IS_ERR(req)) { | |
584aa810 FI |
514 | result = PTR_ERR(req); |
515 | break; | |
516 | } | |
517 | req->wb_index = pos >> PAGE_SHIFT; | |
518 | req->wb_offset = pos & ~PAGE_MASK; | |
91f79c43 AV |
519 | if (!nfs_pageio_add_request(&desc, req)) { |
520 | result = desc.pg_error; | |
584aa810 | 521 | nfs_release_request(req); |
584aa810 FI |
522 | break; |
523 | } | |
524 | pgbase = 0; | |
525 | bytes -= req_len; | |
91f79c43 | 526 | requested_bytes += req_len; |
584aa810 | 527 | pos += req_len; |
35754bc0 | 528 | dreq->bytes_left -= req_len; |
584aa810 | 529 | } |
6d74743b | 530 | nfs_direct_release_pages(pagevec, npages); |
91f79c43 | 531 | kvfree(pagevec); |
19f73787 CL |
532 | if (result < 0) |
533 | break; | |
19f73787 CL |
534 | } |
535 | ||
584aa810 FI |
536 | nfs_pageio_complete(&desc); |
537 | ||
839f7ad6 CL |
538 | /* |
539 | * If no bytes were started, return the error, and let the | |
540 | * generic layer handle the completion. | |
541 | */ | |
542 | if (requested_bytes == 0) { | |
fe0f07d0 | 543 | inode_dio_end(inode); |
839f7ad6 CL |
544 | nfs_direct_req_release(dreq); |
545 | return result < 0 ? result : -EIO; | |
546 | } | |
547 | ||
19f73787 | 548 | if (put_dreq(dreq)) |
9811cd57 | 549 | nfs_direct_complete(dreq, false); |
839f7ad6 | 550 | return 0; |
19f73787 CL |
551 | } |
552 | ||
14a3ec79 CH |
553 | /** |
554 | * nfs_file_direct_read - file direct read operation for NFS files | |
555 | * @iocb: target I/O control block | |
619d30b4 | 556 | * @iter: vector of user buffers into which to read data |
14a3ec79 CH |
557 | * |
558 | * We use this function for direct reads instead of calling | |
559 | * generic_file_aio_read() in order to avoid gfar's check to see if | |
560 | * the request starts before the end of the file. For that check | |
561 | * to work, we must generate a GETATTR before each direct read, and | |
562 | * even then there is a window between the GETATTR and the subsequent | |
563 | * READ where the file size could change. Our preference is simply | |
564 | * to do all reads the application wants, and the server will take | |
565 | * care of managing the end of file boundary. | |
566 | * | |
567 | * This function also eliminates unnecessarily updating the file's | |
568 | * atime locally, as the NFS server sets the file's atime, and this | |
569 | * client must read the updated atime from the server back into its | |
570 | * cache. | |
571 | */ | |
c8b8e32d | 572 | ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter) |
1da177e4 | 573 | { |
14a3ec79 CH |
574 | struct file *file = iocb->ki_filp; |
575 | struct address_space *mapping = file->f_mapping; | |
576 | struct inode *inode = mapping->host; | |
1da177e4 | 577 | struct nfs_direct_req *dreq; |
b3c54de6 | 578 | struct nfs_lock_context *l_ctx; |
14a3ec79 | 579 | ssize_t result = -EINVAL; |
a6cbcd4a | 580 | size_t count = iov_iter_count(iter); |
14a3ec79 CH |
581 | nfs_add_stats(mapping->host, NFSIOS_DIRECTREADBYTES, count); |
582 | ||
583 | dfprintk(FILE, "NFS: direct read(%pD2, %zd@%Ld)\n", | |
c8b8e32d | 584 | file, count, (long long) iocb->ki_pos); |
14a3ec79 CH |
585 | |
586 | result = 0; | |
587 | if (!count) | |
588 | goto out; | |
589 | ||
5955102c | 590 | inode_lock(inode); |
14a3ec79 CH |
591 | result = nfs_sync_mapping(mapping); |
592 | if (result) | |
d0b9875d | 593 | goto out_unlock; |
1da177e4 | 594 | |
14a3ec79 CH |
595 | task_io_account_read(count); |
596 | ||
597 | result = -ENOMEM; | |
607f31e8 | 598 | dreq = nfs_direct_req_alloc(); |
f11ac8db | 599 | if (dreq == NULL) |
d0b9875d | 600 | goto out_unlock; |
1da177e4 | 601 | |
91d5b470 | 602 | dreq->inode = inode; |
ed3743a6 | 603 | dreq->bytes_left = dreq->max_count = count; |
c8b8e32d | 604 | dreq->io_start = iocb->ki_pos; |
cd3758e3 | 605 | dreq->ctx = get_nfs_open_context(nfs_file_open_context(iocb->ki_filp)); |
b3c54de6 TM |
606 | l_ctx = nfs_get_lock_context(dreq->ctx); |
607 | if (IS_ERR(l_ctx)) { | |
608 | result = PTR_ERR(l_ctx); | |
f11ac8db | 609 | goto out_release; |
b3c54de6 TM |
610 | } |
611 | dreq->l_ctx = l_ctx; | |
487b8372 CL |
612 | if (!is_sync_kiocb(iocb)) |
613 | dreq->iocb = iocb; | |
1da177e4 | 614 | |
619d30b4 | 615 | NFS_I(inode)->read_io += count; |
c8b8e32d | 616 | result = nfs_direct_read_schedule_iovec(dreq, iter, iocb->ki_pos); |
d0b9875d | 617 | |
5955102c | 618 | inode_unlock(inode); |
d0b9875d | 619 | |
14a3ec79 | 620 | if (!result) { |
607f31e8 | 621 | result = nfs_direct_wait(dreq); |
14a3ec79 | 622 | if (result > 0) |
c8b8e32d | 623 | iocb->ki_pos += result; |
14a3ec79 | 624 | } |
d0b9875d CH |
625 | |
626 | nfs_direct_req_release(dreq); | |
627 | return result; | |
628 | ||
f11ac8db | 629 | out_release: |
b4946ffb | 630 | nfs_direct_req_release(dreq); |
d0b9875d | 631 | out_unlock: |
5955102c | 632 | inode_unlock(inode); |
f11ac8db | 633 | out: |
1da177e4 LT |
634 | return result; |
635 | } | |
636 | ||
085d1e33 TH |
637 | static void |
638 | nfs_direct_write_scan_commit_list(struct inode *inode, | |
639 | struct list_head *list, | |
640 | struct nfs_commit_info *cinfo) | |
641 | { | |
fe238e60 | 642 | spin_lock(&cinfo->inode->i_lock); |
085d1e33 TH |
643 | #ifdef CONFIG_NFS_V4_1 |
644 | if (cinfo->ds != NULL && cinfo->ds->nwritten != 0) | |
645 | NFS_SERVER(inode)->pnfs_curr_ld->recover_commit_reqs(list, cinfo); | |
646 | #endif | |
647 | nfs_scan_commit_list(&cinfo->mds->list, list, cinfo, 0); | |
fe238e60 | 648 | spin_unlock(&cinfo->inode->i_lock); |
085d1e33 TH |
649 | } |
650 | ||
fad61490 TM |
651 | static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq) |
652 | { | |
1763da12 FI |
653 | struct nfs_pageio_descriptor desc; |
654 | struct nfs_page *req, *tmp; | |
655 | LIST_HEAD(reqs); | |
656 | struct nfs_commit_info cinfo; | |
657 | LIST_HEAD(failed); | |
0a00b77b | 658 | int i; |
1763da12 FI |
659 | |
660 | nfs_init_cinfo_from_dreq(&cinfo, dreq); | |
085d1e33 | 661 | nfs_direct_write_scan_commit_list(dreq->inode, &reqs, &cinfo); |
1da177e4 | 662 | |
fad61490 | 663 | dreq->count = 0; |
0a00b77b WAA |
664 | for (i = 0; i < dreq->mirror_count; i++) |
665 | dreq->mirrors[i].count = 0; | |
607f31e8 TM |
666 | get_dreq(dreq); |
667 | ||
a20c93e3 | 668 | nfs_pageio_init_write(&desc, dreq->inode, FLUSH_STABLE, false, |
1763da12 FI |
669 | &nfs_direct_write_completion_ops); |
670 | desc.pg_dreq = dreq; | |
fedb595c | 671 | |
0a00b77b WAA |
672 | req = nfs_list_entry(reqs.next); |
673 | nfs_direct_setup_mirroring(dreq, &desc, req); | |
d600ad1f PT |
674 | if (desc.pg_error < 0) { |
675 | list_splice_init(&reqs, &failed); | |
676 | goto out_failed; | |
677 | } | |
0a00b77b | 678 | |
1763da12 FI |
679 | list_for_each_entry_safe(req, tmp, &reqs, wb_list) { |
680 | if (!nfs_pageio_add_request(&desc, req)) { | |
4035c248 | 681 | nfs_list_remove_request(req); |
1763da12 | 682 | nfs_list_add_request(req, &failed); |
fe238e60 | 683 | spin_lock(&cinfo.inode->i_lock); |
1763da12 | 684 | dreq->flags = 0; |
d600ad1f PT |
685 | if (desc.pg_error < 0) |
686 | dreq->error = desc.pg_error; | |
687 | else | |
688 | dreq->error = -EIO; | |
fe238e60 | 689 | spin_unlock(&cinfo.inode->i_lock); |
1763da12 | 690 | } |
5a695da2 | 691 | nfs_release_request(req); |
1763da12 FI |
692 | } |
693 | nfs_pageio_complete(&desc); | |
fad61490 | 694 | |
d600ad1f | 695 | out_failed: |
4035c248 TM |
696 | while (!list_empty(&failed)) { |
697 | req = nfs_list_entry(failed.next); | |
698 | nfs_list_remove_request(req); | |
1d1afcbc | 699 | nfs_unlock_and_release_request(req); |
4035c248 | 700 | } |
fad61490 | 701 | |
1763da12 FI |
702 | if (put_dreq(dreq)) |
703 | nfs_direct_write_complete(dreq, dreq->inode); | |
c9d8f89d TM |
704 | } |
705 | ||
1763da12 | 706 | static void nfs_direct_commit_complete(struct nfs_commit_data *data) |
c9d8f89d | 707 | { |
0b7c0153 | 708 | struct nfs_direct_req *dreq = data->dreq; |
1763da12 FI |
709 | struct nfs_commit_info cinfo; |
710 | struct nfs_page *req; | |
c9d8f89d TM |
711 | int status = data->task.tk_status; |
712 | ||
1763da12 | 713 | nfs_init_cinfo_from_dreq(&cinfo, dreq); |
c9d8f89d | 714 | if (status < 0) { |
60fa3f76 | 715 | dprintk("NFS: %5u commit failed with error %d.\n", |
1763da12 | 716 | data->task.tk_pid, status); |
fad61490 | 717 | dreq->flags = NFS_ODIRECT_RESCHED_WRITES; |
5002c586 | 718 | } else if (nfs_direct_cmp_commit_data_verf(dreq, data)) { |
c9d8f89d | 719 | dprintk("NFS: %5u commit verify failed\n", data->task.tk_pid); |
fad61490 | 720 | dreq->flags = NFS_ODIRECT_RESCHED_WRITES; |
1da177e4 LT |
721 | } |
722 | ||
c9d8f89d | 723 | dprintk("NFS: %5u commit returned %d\n", data->task.tk_pid, status); |
1763da12 FI |
724 | while (!list_empty(&data->pages)) { |
725 | req = nfs_list_entry(data->pages.next); | |
726 | nfs_list_remove_request(req); | |
727 | if (dreq->flags == NFS_ODIRECT_RESCHED_WRITES) { | |
728 | /* Note the rewrite will go through mds */ | |
b57ff130 | 729 | nfs_mark_request_commit(req, NULL, &cinfo, 0); |
906369e4 FI |
730 | } else |
731 | nfs_release_request(req); | |
1d1afcbc | 732 | nfs_unlock_and_release_request(req); |
1763da12 FI |
733 | } |
734 | ||
735 | if (atomic_dec_and_test(&cinfo.mds->rpcs_out)) | |
736 | nfs_direct_write_complete(dreq, data->inode); | |
1da177e4 LT |
737 | } |
738 | ||
b20135d0 TM |
739 | static void nfs_direct_resched_write(struct nfs_commit_info *cinfo, |
740 | struct nfs_page *req) | |
1763da12 | 741 | { |
b20135d0 TM |
742 | struct nfs_direct_req *dreq = cinfo->dreq; |
743 | ||
744 | spin_lock(&dreq->lock); | |
745 | dreq->flags = NFS_ODIRECT_RESCHED_WRITES; | |
746 | spin_unlock(&dreq->lock); | |
747 | nfs_mark_request_commit(req, NULL, cinfo, 0); | |
1763da12 FI |
748 | } |
749 | ||
750 | static const struct nfs_commit_completion_ops nfs_direct_commit_completion_ops = { | |
751 | .completion = nfs_direct_commit_complete, | |
b20135d0 | 752 | .resched_write = nfs_direct_resched_write, |
fad61490 TM |
753 | }; |
754 | ||
755 | static void nfs_direct_commit_schedule(struct nfs_direct_req *dreq) | |
1da177e4 | 756 | { |
1763da12 FI |
757 | int res; |
758 | struct nfs_commit_info cinfo; | |
759 | LIST_HEAD(mds_list); | |
760 | ||
761 | nfs_init_cinfo_from_dreq(&cinfo, dreq); | |
762 | nfs_scan_commit(dreq->inode, &mds_list, &cinfo); | |
763 | res = nfs_generic_commit_list(dreq->inode, &mds_list, 0, &cinfo); | |
764 | if (res < 0) /* res == -ENOMEM */ | |
765 | nfs_direct_write_reschedule(dreq); | |
fad61490 | 766 | } |
1da177e4 | 767 | |
1763da12 | 768 | static void nfs_direct_write_schedule_work(struct work_struct *work) |
fad61490 | 769 | { |
1763da12 | 770 | struct nfs_direct_req *dreq = container_of(work, struct nfs_direct_req, work); |
fad61490 | 771 | int flags = dreq->flags; |
1da177e4 | 772 | |
fad61490 TM |
773 | dreq->flags = 0; |
774 | switch (flags) { | |
775 | case NFS_ODIRECT_DO_COMMIT: | |
776 | nfs_direct_commit_schedule(dreq); | |
1da177e4 | 777 | break; |
fad61490 TM |
778 | case NFS_ODIRECT_RESCHED_WRITES: |
779 | nfs_direct_write_reschedule(dreq); | |
780 | break; | |
781 | default: | |
9811cd57 | 782 | nfs_direct_complete(dreq, true); |
fad61490 TM |
783 | } |
784 | } | |
1da177e4 | 785 | |
1763da12 | 786 | static void nfs_direct_write_complete(struct nfs_direct_req *dreq, struct inode *inode) |
fad61490 | 787 | { |
1763da12 | 788 | schedule_work(&dreq->work); /* Calls nfs_direct_write_schedule_work */ |
fad61490 | 789 | } |
1763da12 | 790 | |
1763da12 FI |
791 | static void nfs_direct_write_completion(struct nfs_pgio_header *hdr) |
792 | { | |
793 | struct nfs_direct_req *dreq = hdr->dreq; | |
794 | struct nfs_commit_info cinfo; | |
c65e6254 | 795 | bool request_commit = false; |
1763da12 FI |
796 | struct nfs_page *req = nfs_list_entry(hdr->pages.next); |
797 | ||
798 | if (test_bit(NFS_IOHDR_REDO, &hdr->flags)) | |
799 | goto out_put; | |
800 | ||
801 | nfs_init_cinfo_from_dreq(&cinfo, dreq); | |
802 | ||
803 | spin_lock(&dreq->lock); | |
804 | ||
805 | if (test_bit(NFS_IOHDR_ERROR, &hdr->flags)) { | |
806 | dreq->flags = 0; | |
807 | dreq->error = hdr->error; | |
808 | } | |
c65e6254 | 809 | if (dreq->error == 0) { |
0a00b77b | 810 | nfs_direct_good_bytes(dreq, hdr); |
c65e6254 | 811 | if (nfs_write_need_commit(hdr)) { |
1763da12 | 812 | if (dreq->flags == NFS_ODIRECT_RESCHED_WRITES) |
c65e6254 | 813 | request_commit = true; |
1763da12 | 814 | else if (dreq->flags == 0) { |
5002c586 | 815 | nfs_direct_set_hdr_verf(dreq, hdr); |
c65e6254 | 816 | request_commit = true; |
1763da12 FI |
817 | dreq->flags = NFS_ODIRECT_DO_COMMIT; |
818 | } else if (dreq->flags == NFS_ODIRECT_DO_COMMIT) { | |
c65e6254 WAA |
819 | request_commit = true; |
820 | if (nfs_direct_set_or_cmp_hdr_verf(dreq, hdr)) | |
5002c586 WAA |
821 | dreq->flags = |
822 | NFS_ODIRECT_RESCHED_WRITES; | |
1763da12 FI |
823 | } |
824 | } | |
825 | } | |
826 | spin_unlock(&dreq->lock); | |
827 | ||
828 | while (!list_empty(&hdr->pages)) { | |
2bfc6e56 | 829 | |
1763da12 FI |
830 | req = nfs_list_entry(hdr->pages.next); |
831 | nfs_list_remove_request(req); | |
c65e6254 | 832 | if (request_commit) { |
04277086 | 833 | kref_get(&req->wb_kref); |
b57ff130 WAA |
834 | nfs_mark_request_commit(req, hdr->lseg, &cinfo, |
835 | hdr->ds_commit_idx); | |
1763da12 | 836 | } |
1d1afcbc | 837 | nfs_unlock_and_release_request(req); |
1763da12 FI |
838 | } |
839 | ||
840 | out_put: | |
841 | if (put_dreq(dreq)) | |
842 | nfs_direct_write_complete(dreq, hdr->inode); | |
843 | hdr->release(hdr); | |
844 | } | |
845 | ||
3e9e0ca3 TM |
846 | static void nfs_write_sync_pgio_error(struct list_head *head) |
847 | { | |
848 | struct nfs_page *req; | |
849 | ||
850 | while (!list_empty(head)) { | |
851 | req = nfs_list_entry(head->next); | |
852 | nfs_list_remove_request(req); | |
1d1afcbc | 853 | nfs_unlock_and_release_request(req); |
3e9e0ca3 TM |
854 | } |
855 | } | |
856 | ||
dc602dd7 TM |
857 | static void nfs_direct_write_reschedule_io(struct nfs_pgio_header *hdr) |
858 | { | |
859 | struct nfs_direct_req *dreq = hdr->dreq; | |
860 | ||
861 | spin_lock(&dreq->lock); | |
862 | if (dreq->error == 0) { | |
863 | dreq->flags = NFS_ODIRECT_RESCHED_WRITES; | |
864 | /* fake unstable write to let common nfs resend pages */ | |
865 | hdr->verf.committed = NFS_UNSTABLE; | |
866 | hdr->good_bytes = hdr->args.count; | |
867 | } | |
868 | spin_unlock(&dreq->lock); | |
869 | } | |
870 | ||
1763da12 | 871 | static const struct nfs_pgio_completion_ops nfs_direct_write_completion_ops = { |
3e9e0ca3 | 872 | .error_cleanup = nfs_write_sync_pgio_error, |
1763da12 FI |
873 | .init_hdr = nfs_direct_pgio_init, |
874 | .completion = nfs_direct_write_completion, | |
dc602dd7 | 875 | .reschedule_io = nfs_direct_write_reschedule_io, |
1763da12 FI |
876 | }; |
877 | ||
91f79c43 AV |
878 | |
879 | /* | |
880 | * NB: Return the value of the first error return code. Subsequent | |
881 | * errors after the first one are ignored. | |
882 | */ | |
883 | /* | |
884 | * For each wsize'd chunk of the user's buffer, dispatch an NFS WRITE | |
885 | * operation. If nfs_writedata_alloc() or get_user_pages() fails, | |
886 | * bail and stop sending more writes. Write length accounting is | |
887 | * handled automatically by nfs_direct_write_result(). Otherwise, if | |
888 | * no requests have been sent, just return an error. | |
889 | */ | |
19f73787 | 890 | static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq, |
619d30b4 | 891 | struct iov_iter *iter, |
91f79c43 | 892 | loff_t pos) |
19f73787 | 893 | { |
1763da12 | 894 | struct nfs_pageio_descriptor desc; |
1d59d61f | 895 | struct inode *inode = dreq->inode; |
19f73787 CL |
896 | ssize_t result = 0; |
897 | size_t requested_bytes = 0; | |
91f79c43 | 898 | size_t wsize = max_t(size_t, NFS_SERVER(inode)->wsize, PAGE_SIZE); |
19f73787 | 899 | |
a20c93e3 | 900 | nfs_pageio_init_write(&desc, inode, FLUSH_COND_STABLE, false, |
1763da12 FI |
901 | &nfs_direct_write_completion_ops); |
902 | desc.pg_dreq = dreq; | |
19f73787 | 903 | get_dreq(dreq); |
fe0f07d0 | 904 | inode_dio_begin(inode); |
19f73787 | 905 | |
91f79c43 AV |
906 | NFS_I(inode)->write_io += iov_iter_count(iter); |
907 | while (iov_iter_count(iter)) { | |
908 | struct page **pagevec; | |
909 | size_t bytes; | |
910 | size_t pgbase; | |
911 | unsigned npages, i; | |
912 | ||
913 | result = iov_iter_get_pages_alloc(iter, &pagevec, | |
914 | wsize, &pgbase); | |
19f73787 CL |
915 | if (result < 0) |
916 | break; | |
91f79c43 AV |
917 | |
918 | bytes = result; | |
919 | iov_iter_advance(iter, bytes); | |
920 | npages = (result + pgbase + PAGE_SIZE - 1) / PAGE_SIZE; | |
921 | for (i = 0; i < npages; i++) { | |
922 | struct nfs_page *req; | |
923 | unsigned int req_len = min_t(size_t, bytes, PAGE_SIZE - pgbase); | |
924 | ||
16b90578 | 925 | req = nfs_create_request(dreq->ctx, pagevec[i], NULL, |
91f79c43 AV |
926 | pgbase, req_len); |
927 | if (IS_ERR(req)) { | |
928 | result = PTR_ERR(req); | |
929 | break; | |
930 | } | |
0a00b77b WAA |
931 | |
932 | nfs_direct_setup_mirroring(dreq, &desc, req); | |
d600ad1f PT |
933 | if (desc.pg_error < 0) { |
934 | nfs_free_request(req); | |
935 | result = desc.pg_error; | |
936 | break; | |
937 | } | |
0a00b77b | 938 | |
91f79c43 AV |
939 | nfs_lock_request(req); |
940 | req->wb_index = pos >> PAGE_SHIFT; | |
941 | req->wb_offset = pos & ~PAGE_MASK; | |
942 | if (!nfs_pageio_add_request(&desc, req)) { | |
943 | result = desc.pg_error; | |
944 | nfs_unlock_and_release_request(req); | |
945 | break; | |
946 | } | |
947 | pgbase = 0; | |
948 | bytes -= req_len; | |
949 | requested_bytes += req_len; | |
950 | pos += req_len; | |
951 | dreq->bytes_left -= req_len; | |
952 | } | |
953 | nfs_direct_release_pages(pagevec, npages); | |
954 | kvfree(pagevec); | |
955 | if (result < 0) | |
19f73787 | 956 | break; |
19f73787 | 957 | } |
1763da12 | 958 | nfs_pageio_complete(&desc); |
19f73787 | 959 | |
839f7ad6 CL |
960 | /* |
961 | * If no bytes were started, return the error, and let the | |
962 | * generic layer handle the completion. | |
963 | */ | |
964 | if (requested_bytes == 0) { | |
fe0f07d0 | 965 | inode_dio_end(inode); |
839f7ad6 CL |
966 | nfs_direct_req_release(dreq); |
967 | return result < 0 ? result : -EIO; | |
968 | } | |
969 | ||
19f73787 CL |
970 | if (put_dreq(dreq)) |
971 | nfs_direct_write_complete(dreq, dreq->inode); | |
839f7ad6 | 972 | return 0; |
19f73787 CL |
973 | } |
974 | ||
1da177e4 LT |
975 | /** |
976 | * nfs_file_direct_write - file direct write operation for NFS files | |
977 | * @iocb: target I/O control block | |
619d30b4 | 978 | * @iter: vector of user buffers from which to write data |
1da177e4 LT |
979 | * |
980 | * We use this function for direct writes instead of calling | |
981 | * generic_file_aio_write() in order to avoid taking the inode | |
982 | * semaphore and updating the i_size. The NFS server will set | |
983 | * the new i_size and this client must read the updated size | |
984 | * back into its cache. We let the server do generic write | |
985 | * parameter checking and report problems. | |
986 | * | |
1da177e4 LT |
987 | * We eliminate local atime updates, see direct read above. |
988 | * | |
989 | * We avoid unnecessary page cache invalidations for normal cached | |
990 | * readers of this file. | |
991 | * | |
992 | * Note that O_APPEND is not supported for NFS direct writes, as there | |
993 | * is no atomic O_APPEND write facility in the NFS protocol. | |
994 | */ | |
65a4a1ca | 995 | ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter) |
1da177e4 | 996 | { |
22cd1bf1 | 997 | ssize_t result = -EINVAL; |
1da177e4 | 998 | struct file *file = iocb->ki_filp; |
1da177e4 | 999 | struct address_space *mapping = file->f_mapping; |
22cd1bf1 CH |
1000 | struct inode *inode = mapping->host; |
1001 | struct nfs_direct_req *dreq; | |
1002 | struct nfs_lock_context *l_ctx; | |
65a4a1ca | 1003 | loff_t pos, end; |
c216fd70 | 1004 | |
6de1472f | 1005 | dfprintk(FILE, "NFS: direct write(%pD2, %zd@%Ld)\n", |
3309dd04 | 1006 | file, iov_iter_count(iter), (long long) iocb->ki_pos); |
027445c3 | 1007 | |
3309dd04 AV |
1008 | nfs_add_stats(mapping->host, NFSIOS_DIRECTWRITTENBYTES, |
1009 | iov_iter_count(iter)); | |
1010 | ||
1011 | pos = iocb->ki_pos; | |
09cbfeaf | 1012 | end = (pos + iov_iter_count(iter) - 1) >> PAGE_SHIFT; |
ce1a8e67 | 1013 | |
5955102c | 1014 | inode_lock(inode); |
a9ab5e84 | 1015 | |
22cd1bf1 CH |
1016 | result = nfs_sync_mapping(mapping); |
1017 | if (result) | |
a9ab5e84 CH |
1018 | goto out_unlock; |
1019 | ||
1020 | if (mapping->nrpages) { | |
1021 | result = invalidate_inode_pages2_range(mapping, | |
09cbfeaf | 1022 | pos >> PAGE_SHIFT, end); |
a9ab5e84 CH |
1023 | if (result) |
1024 | goto out_unlock; | |
1025 | } | |
1da177e4 | 1026 | |
3309dd04 | 1027 | task_io_account_write(iov_iter_count(iter)); |
7ec10f26 | 1028 | |
22cd1bf1 CH |
1029 | result = -ENOMEM; |
1030 | dreq = nfs_direct_req_alloc(); | |
1031 | if (!dreq) | |
a9ab5e84 | 1032 | goto out_unlock; |
9eafa8cc | 1033 | |
22cd1bf1 | 1034 | dreq->inode = inode; |
ed3743a6 | 1035 | dreq->bytes_left = dreq->max_count = iov_iter_count(iter); |
5fadeb47 | 1036 | dreq->io_start = pos; |
22cd1bf1 CH |
1037 | dreq->ctx = get_nfs_open_context(nfs_file_open_context(iocb->ki_filp)); |
1038 | l_ctx = nfs_get_lock_context(dreq->ctx); | |
1039 | if (IS_ERR(l_ctx)) { | |
1040 | result = PTR_ERR(l_ctx); | |
1041 | goto out_release; | |
1042 | } | |
1043 | dreq->l_ctx = l_ctx; | |
1044 | if (!is_sync_kiocb(iocb)) | |
1045 | dreq->iocb = iocb; | |
1046 | ||
91f79c43 | 1047 | result = nfs_direct_write_schedule_iovec(dreq, iter, pos); |
a9ab5e84 CH |
1048 | |
1049 | if (mapping->nrpages) { | |
1050 | invalidate_inode_pages2_range(mapping, | |
09cbfeaf | 1051 | pos >> PAGE_SHIFT, end); |
a9ab5e84 CH |
1052 | } |
1053 | ||
5955102c | 1054 | inode_unlock(inode); |
a9ab5e84 | 1055 | |
22cd1bf1 CH |
1056 | if (!result) { |
1057 | result = nfs_direct_wait(dreq); | |
1058 | if (result > 0) { | |
1059 | struct inode *inode = mapping->host; | |
1060 | ||
1061 | iocb->ki_pos = pos + result; | |
1062 | spin_lock(&inode->i_lock); | |
1063 | if (i_size_read(inode) < iocb->ki_pos) | |
1064 | i_size_write(inode, iocb->ki_pos); | |
1065 | spin_unlock(&inode->i_lock); | |
e2592217 CH |
1066 | |
1067 | /* XXX: should check the generic_write_sync retval */ | |
1068 | generic_write_sync(iocb, result); | |
22cd1bf1 | 1069 | } |
1763da12 | 1070 | } |
a9ab5e84 CH |
1071 | nfs_direct_req_release(dreq); |
1072 | return result; | |
1073 | ||
22cd1bf1 CH |
1074 | out_release: |
1075 | nfs_direct_req_release(dreq); | |
a9ab5e84 | 1076 | out_unlock: |
5955102c | 1077 | inode_unlock(inode); |
22cd1bf1 | 1078 | return result; |
1da177e4 LT |
1079 | } |
1080 | ||
88467055 CL |
1081 | /** |
1082 | * nfs_init_directcache - create a slab cache for nfs_direct_req structures | |
1083 | * | |
1084 | */ | |
f7b422b1 | 1085 | int __init nfs_init_directcache(void) |
1da177e4 LT |
1086 | { |
1087 | nfs_direct_cachep = kmem_cache_create("nfs_direct_cache", | |
1088 | sizeof(struct nfs_direct_req), | |
fffb60f9 PJ |
1089 | 0, (SLAB_RECLAIM_ACCOUNT| |
1090 | SLAB_MEM_SPREAD), | |
20c2df83 | 1091 | NULL); |
1da177e4 LT |
1092 | if (nfs_direct_cachep == NULL) |
1093 | return -ENOMEM; | |
1094 | ||
1095 | return 0; | |
1096 | } | |
1097 | ||
88467055 | 1098 | /** |
f7b422b1 | 1099 | * nfs_destroy_directcache - destroy the slab cache for nfs_direct_req structures |
88467055 CL |
1100 | * |
1101 | */ | |
266bee88 | 1102 | void nfs_destroy_directcache(void) |
1da177e4 | 1103 | { |
1a1d92c1 | 1104 | kmem_cache_destroy(nfs_direct_cachep); |
1da177e4 | 1105 | } |