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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * linux/fs/nfs/pagelist.c | |
4 | * | |
5 | * A set of helper functions for managing NFS read and write requests. | |
6 | * The main purpose of these routines is to provide support for the | |
7 | * coalescing of several requests into a single RPC call. | |
8 | * | |
9 | * Copyright 2000, 2001 (c) Trond Myklebust <trond.myklebust@fys.uio.no> | |
10 | * | |
11 | */ | |
12 | ||
1da177e4 LT |
13 | #include <linux/slab.h> |
14 | #include <linux/file.h> | |
e8edc6e0 | 15 | #include <linux/sched.h> |
1da177e4 | 16 | #include <linux/sunrpc/clnt.h> |
1313e603 | 17 | #include <linux/nfs.h> |
1da177e4 LT |
18 | #include <linux/nfs3.h> |
19 | #include <linux/nfs4.h> | |
1da177e4 | 20 | #include <linux/nfs_fs.h> |
33344e0f | 21 | #include <linux/nfs_page.h> |
1da177e4 | 22 | #include <linux/nfs_mount.h> |
afeacc8c | 23 | #include <linux/export.h> |
1da177e4 | 24 | |
8d5658c9 | 25 | #include "internal.h" |
bae724ef | 26 | #include "pnfs.h" |
8d5658c9 | 27 | |
0eecb214 AS |
28 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE |
29 | ||
e18b890b | 30 | static struct kmem_cache *nfs_page_cachep; |
ef2c488c | 31 | static const struct rpc_call_ops nfs_pgio_common_ops; |
1da177e4 | 32 | |
48d635f1 PT |
33 | struct nfs_pgio_mirror * |
34 | nfs_pgio_current_mirror(struct nfs_pageio_descriptor *desc) | |
35 | { | |
36 | return nfs_pgio_has_mirroring(desc) ? | |
37 | &desc->pg_mirrors[desc->pg_mirror_idx] : | |
38 | &desc->pg_mirrors[0]; | |
39 | } | |
40 | EXPORT_SYMBOL_GPL(nfs_pgio_current_mirror); | |
41 | ||
4db6e0b7 FI |
42 | void nfs_pgheader_init(struct nfs_pageio_descriptor *desc, |
43 | struct nfs_pgio_header *hdr, | |
44 | void (*release)(struct nfs_pgio_header *hdr)) | |
45 | { | |
48d635f1 | 46 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb WAA |
47 | |
48 | ||
49 | hdr->req = nfs_list_entry(mirror->pg_list.next); | |
4db6e0b7 | 50 | hdr->inode = desc->pg_inode; |
9fcd5960 | 51 | hdr->cred = nfs_req_openctx(hdr->req)->cred; |
4db6e0b7 | 52 | hdr->io_start = req_offset(hdr->req); |
a7d42ddb | 53 | hdr->good_bytes = mirror->pg_count; |
919e3bd9 | 54 | hdr->io_completion = desc->pg_io_completion; |
584aa810 | 55 | hdr->dreq = desc->pg_dreq; |
4db6e0b7 | 56 | hdr->release = release; |
061ae2ed | 57 | hdr->completion_ops = desc->pg_completion_ops; |
584aa810 FI |
58 | if (hdr->completion_ops->init_hdr) |
59 | hdr->completion_ops->init_hdr(hdr); | |
a7d42ddb WAA |
60 | |
61 | hdr->pgio_mirror_idx = desc->pg_mirror_idx; | |
4db6e0b7 | 62 | } |
89d77c8f | 63 | EXPORT_SYMBOL_GPL(nfs_pgheader_init); |
4db6e0b7 FI |
64 | |
65 | void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos) | |
66 | { | |
1c6c4b74 TM |
67 | unsigned int new = pos - hdr->io_start; |
68 | ||
69 | if (hdr->good_bytes > new) { | |
70 | hdr->good_bytes = new; | |
4db6e0b7 | 71 | clear_bit(NFS_IOHDR_EOF, &hdr->flags); |
1c6c4b74 TM |
72 | if (!test_and_set_bit(NFS_IOHDR_ERROR, &hdr->flags)) |
73 | hdr->error = error; | |
4db6e0b7 | 74 | } |
4db6e0b7 FI |
75 | } |
76 | ||
1da177e4 LT |
77 | static inline struct nfs_page * |
78 | nfs_page_alloc(void) | |
79 | { | |
2b17d725 | 80 | struct nfs_page *p = kmem_cache_zalloc(nfs_page_cachep, GFP_KERNEL); |
72895b1a | 81 | if (p) |
1da177e4 | 82 | INIT_LIST_HEAD(&p->wb_list); |
1da177e4 LT |
83 | return p; |
84 | } | |
85 | ||
86 | static inline void | |
87 | nfs_page_free(struct nfs_page *p) | |
88 | { | |
89 | kmem_cache_free(nfs_page_cachep, p); | |
90 | } | |
91 | ||
577b4232 TM |
92 | /** |
93 | * nfs_iocounter_wait - wait for i/o to complete | |
210c7c17 | 94 | * @l_ctx: nfs_lock_context with io_counter to use |
577b4232 TM |
95 | * |
96 | * returns -ERESTARTSYS if interrupted by a fatal signal. | |
97 | * Otherwise returns 0 once the io_count hits 0. | |
98 | */ | |
99 | int | |
210c7c17 | 100 | nfs_iocounter_wait(struct nfs_lock_context *l_ctx) |
577b4232 | 101 | { |
723c921e PZ |
102 | return wait_var_event_killable(&l_ctx->io_count, |
103 | !atomic_read(&l_ctx->io_count)); | |
577b4232 TM |
104 | } |
105 | ||
7d6ddf88 BC |
106 | /** |
107 | * nfs_async_iocounter_wait - wait on a rpc_waitqueue for I/O | |
108 | * to complete | |
109 | * @task: the rpc_task that should wait | |
110 | * @l_ctx: nfs_lock_context with io_counter to check | |
111 | * | |
112 | * Returns true if there is outstanding I/O to wait on and the | |
113 | * task has been put to sleep. | |
114 | */ | |
115 | bool | |
116 | nfs_async_iocounter_wait(struct rpc_task *task, struct nfs_lock_context *l_ctx) | |
117 | { | |
118 | struct inode *inode = d_inode(l_ctx->open_context->dentry); | |
119 | bool ret = false; | |
120 | ||
121 | if (atomic_read(&l_ctx->io_count) > 0) { | |
122 | rpc_sleep_on(&NFS_SERVER(inode)->uoc_rpcwaitq, task, NULL); | |
123 | ret = true; | |
124 | } | |
125 | ||
126 | if (atomic_read(&l_ctx->io_count) == 0) { | |
127 | rpc_wake_up_queued_task(&NFS_SERVER(inode)->uoc_rpcwaitq, task); | |
128 | ret = false; | |
129 | } | |
130 | ||
131 | return ret; | |
132 | } | |
133 | EXPORT_SYMBOL_GPL(nfs_async_iocounter_wait); | |
134 | ||
2bfc6e56 | 135 | /* |
aea90c4e TM |
136 | * nfs_page_set_headlock - set the request PG_HEADLOCK |
137 | * @req: request that is to be locked | |
2bfc6e56 | 138 | * |
aea90c4e | 139 | * this lock must be held when modifying req->wb_head |
e7029206 | 140 | * |
1344b7ea | 141 | * return 0 on success, < 0 on error |
2bfc6e56 | 142 | */ |
e7029206 | 143 | int |
aea90c4e | 144 | nfs_page_set_headlock(struct nfs_page *req) |
2bfc6e56 | 145 | { |
aea90c4e | 146 | if (!test_and_set_bit(PG_HEADLOCK, &req->wb_flags)) |
bc8a309e | 147 | return 0; |
e7029206 | 148 | |
aea90c4e | 149 | set_bit(PG_CONTENDED1, &req->wb_flags); |
1344b7ea | 150 | smp_mb__after_atomic(); |
aea90c4e | 151 | return wait_on_bit_lock(&req->wb_flags, PG_HEADLOCK, |
bc8a309e | 152 | TASK_UNINTERRUPTIBLE); |
2bfc6e56 WAA |
153 | } |
154 | ||
155 | /* | |
aea90c4e TM |
156 | * nfs_page_clear_headlock - clear the request PG_HEADLOCK |
157 | * @req: request that is to be locked | |
2bfc6e56 WAA |
158 | */ |
159 | void | |
aea90c4e | 160 | nfs_page_clear_headlock(struct nfs_page *req) |
2bfc6e56 | 161 | { |
d1e1cda8 | 162 | smp_mb__before_atomic(); |
aea90c4e | 163 | clear_bit(PG_HEADLOCK, &req->wb_flags); |
d1e1cda8 | 164 | smp_mb__after_atomic(); |
aea90c4e | 165 | if (!test_bit(PG_CONTENDED1, &req->wb_flags)) |
b4f937cf | 166 | return; |
aea90c4e TM |
167 | wake_up_bit(&req->wb_flags, PG_HEADLOCK); |
168 | } | |
169 | ||
170 | /* | |
171 | * nfs_page_group_lock - lock the head of the page group | |
172 | * @req: request in group that is to be locked | |
173 | * | |
174 | * this lock must be held when traversing or modifying the page | |
175 | * group list | |
176 | * | |
177 | * return 0 on success, < 0 on error | |
178 | */ | |
179 | int | |
180 | nfs_page_group_lock(struct nfs_page *req) | |
181 | { | |
182 | int ret; | |
183 | ||
184 | ret = nfs_page_set_headlock(req); | |
185 | if (ret || req->wb_head == req) | |
186 | return ret; | |
187 | return nfs_page_set_headlock(req->wb_head); | |
188 | } | |
189 | ||
190 | /* | |
191 | * nfs_page_group_unlock - unlock the head of the page group | |
192 | * @req: request in group that is to be unlocked | |
193 | */ | |
194 | void | |
195 | nfs_page_group_unlock(struct nfs_page *req) | |
196 | { | |
197 | if (req != req->wb_head) | |
198 | nfs_page_clear_headlock(req->wb_head); | |
199 | nfs_page_clear_headlock(req); | |
2bfc6e56 WAA |
200 | } |
201 | ||
202 | /* | |
203 | * nfs_page_group_sync_on_bit_locked | |
204 | * | |
205 | * must be called with page group lock held | |
206 | */ | |
207 | static bool | |
208 | nfs_page_group_sync_on_bit_locked(struct nfs_page *req, unsigned int bit) | |
209 | { | |
210 | struct nfs_page *head = req->wb_head; | |
211 | struct nfs_page *tmp; | |
212 | ||
213 | WARN_ON_ONCE(!test_bit(PG_HEADLOCK, &head->wb_flags)); | |
214 | WARN_ON_ONCE(test_and_set_bit(bit, &req->wb_flags)); | |
215 | ||
216 | tmp = req->wb_this_page; | |
217 | while (tmp != req) { | |
218 | if (!test_bit(bit, &tmp->wb_flags)) | |
219 | return false; | |
220 | tmp = tmp->wb_this_page; | |
221 | } | |
222 | ||
223 | /* true! reset all bits */ | |
224 | tmp = req; | |
225 | do { | |
226 | clear_bit(bit, &tmp->wb_flags); | |
227 | tmp = tmp->wb_this_page; | |
228 | } while (tmp != req); | |
229 | ||
230 | return true; | |
231 | } | |
232 | ||
233 | /* | |
234 | * nfs_page_group_sync_on_bit - set bit on current request, but only | |
235 | * return true if the bit is set for all requests in page group | |
236 | * @req - request in page group | |
237 | * @bit - PG_* bit that is used to sync page group | |
238 | */ | |
239 | bool nfs_page_group_sync_on_bit(struct nfs_page *req, unsigned int bit) | |
240 | { | |
241 | bool ret; | |
242 | ||
1344b7ea | 243 | nfs_page_group_lock(req); |
2bfc6e56 WAA |
244 | ret = nfs_page_group_sync_on_bit_locked(req, bit); |
245 | nfs_page_group_unlock(req); | |
246 | ||
247 | return ret; | |
248 | } | |
249 | ||
250 | /* | |
251 | * nfs_page_group_init - Initialize the page group linkage for @req | |
252 | * @req - a new nfs request | |
253 | * @prev - the previous request in page group, or NULL if @req is the first | |
254 | * or only request in the group (the head). | |
255 | */ | |
256 | static inline void | |
257 | nfs_page_group_init(struct nfs_page *req, struct nfs_page *prev) | |
258 | { | |
cb1410c7 | 259 | struct inode *inode; |
2bfc6e56 WAA |
260 | WARN_ON_ONCE(prev == req); |
261 | ||
262 | if (!prev) { | |
85710a83 | 263 | /* a head request */ |
2bfc6e56 WAA |
264 | req->wb_head = req; |
265 | req->wb_this_page = req; | |
266 | } else { | |
85710a83 | 267 | /* a subrequest */ |
2bfc6e56 WAA |
268 | WARN_ON_ONCE(prev->wb_this_page != prev->wb_head); |
269 | WARN_ON_ONCE(!test_bit(PG_HEADLOCK, &prev->wb_head->wb_flags)); | |
270 | req->wb_head = prev->wb_head; | |
271 | req->wb_this_page = prev->wb_this_page; | |
272 | prev->wb_this_page = req; | |
273 | ||
85710a83 WAA |
274 | /* All subrequests take a ref on the head request until |
275 | * nfs_page_group_destroy is called */ | |
276 | kref_get(&req->wb_head->wb_kref); | |
277 | ||
cb1410c7 WAA |
278 | /* grab extra ref and bump the request count if head request |
279 | * has extra ref from the write/commit path to handle handoff | |
280 | * between write and commit lists. */ | |
17089a29 | 281 | if (test_bit(PG_INODE_REF, &prev->wb_head->wb_flags)) { |
cb1410c7 | 282 | inode = page_file_mapping(req->wb_page)->host; |
17089a29 | 283 | set_bit(PG_INODE_REF, &req->wb_flags); |
2bfc6e56 | 284 | kref_get(&req->wb_kref); |
a6b6d5b8 | 285 | atomic_long_inc(&NFS_I(inode)->nrequests); |
17089a29 | 286 | } |
2bfc6e56 WAA |
287 | } |
288 | } | |
289 | ||
290 | /* | |
291 | * nfs_page_group_destroy - sync the destruction of page groups | |
292 | * @req - request that no longer needs the page group | |
293 | * | |
294 | * releases the page group reference from each member once all | |
295 | * members have called this function. | |
296 | */ | |
297 | static void | |
298 | nfs_page_group_destroy(struct kref *kref) | |
299 | { | |
300 | struct nfs_page *req = container_of(kref, struct nfs_page, wb_kref); | |
08fead2a | 301 | struct nfs_page *head = req->wb_head; |
2bfc6e56 WAA |
302 | struct nfs_page *tmp, *next; |
303 | ||
304 | if (!nfs_page_group_sync_on_bit(req, PG_TEARDOWN)) | |
08fead2a | 305 | goto out; |
2bfc6e56 WAA |
306 | |
307 | tmp = req; | |
308 | do { | |
309 | next = tmp->wb_this_page; | |
310 | /* unlink and free */ | |
311 | tmp->wb_this_page = tmp; | |
312 | tmp->wb_head = tmp; | |
313 | nfs_free_request(tmp); | |
314 | tmp = next; | |
315 | } while (tmp != req); | |
08fead2a TM |
316 | out: |
317 | /* subrequests must release the ref on the head request */ | |
318 | if (head != req) | |
319 | nfs_release_request(head); | |
2bfc6e56 WAA |
320 | } |
321 | ||
c917cfaf TM |
322 | static struct nfs_page * |
323 | __nfs_create_request(struct nfs_lock_context *l_ctx, struct page *page, | |
28b1d3f5 TM |
324 | unsigned int pgbase, unsigned int offset, |
325 | unsigned int count) | |
1da177e4 | 326 | { |
1da177e4 | 327 | struct nfs_page *req; |
c917cfaf | 328 | struct nfs_open_context *ctx = l_ctx->open_context; |
1da177e4 | 329 | |
c58c8441 TM |
330 | if (test_bit(NFS_CONTEXT_BAD, &ctx->flags)) |
331 | return ERR_PTR(-EBADF); | |
18eb8842 TM |
332 | /* try to allocate the request struct */ |
333 | req = nfs_page_alloc(); | |
334 | if (req == NULL) | |
335 | return ERR_PTR(-ENOMEM); | |
1da177e4 | 336 | |
b3c54de6 | 337 | req->wb_lock_context = l_ctx; |
c917cfaf | 338 | refcount_inc(&l_ctx->count); |
210c7c17 | 339 | atomic_inc(&l_ctx->io_count); |
015f0212 | 340 | |
1da177e4 LT |
341 | /* Initialize the request struct. Initially, we assume a |
342 | * long write-back delay. This will be adjusted in | |
343 | * update_nfs_request below if the region is not locked. */ | |
344 | req->wb_page = page; | |
67911c8f | 345 | if (page) { |
8cd79788 | 346 | req->wb_index = page_index(page); |
67911c8f AS |
347 | get_page(page); |
348 | } | |
1da177e4 | 349 | req->wb_offset = offset; |
c917cfaf | 350 | req->wb_pgbase = pgbase; |
1da177e4 | 351 | req->wb_bytes = count; |
c03b4024 | 352 | kref_init(&req->wb_kref); |
33344e0f | 353 | req->wb_nio = 0; |
1da177e4 LT |
354 | return req; |
355 | } | |
356 | ||
c917cfaf TM |
357 | /** |
358 | * nfs_create_request - Create an NFS read/write request. | |
359 | * @ctx: open context to use | |
360 | * @page: page to write | |
c917cfaf TM |
361 | * @offset: starting offset within the page for the write |
362 | * @count: number of bytes to read/write | |
363 | * | |
364 | * The page must be locked by the caller. This makes sure we never | |
365 | * create two different requests for the same page. | |
366 | * User should ensure it is safe to sleep in this function. | |
367 | */ | |
368 | struct nfs_page * | |
369 | nfs_create_request(struct nfs_open_context *ctx, struct page *page, | |
28b1d3f5 | 370 | unsigned int offset, unsigned int count) |
c917cfaf TM |
371 | { |
372 | struct nfs_lock_context *l_ctx = nfs_get_lock_context(ctx); | |
373 | struct nfs_page *ret; | |
374 | ||
375 | if (IS_ERR(l_ctx)) | |
376 | return ERR_CAST(l_ctx); | |
28b1d3f5 TM |
377 | ret = __nfs_create_request(l_ctx, page, offset, offset, count); |
378 | if (!IS_ERR(ret)) | |
379 | nfs_page_group_init(ret, NULL); | |
c917cfaf TM |
380 | nfs_put_lock_context(l_ctx); |
381 | return ret; | |
382 | } | |
383 | ||
384 | static struct nfs_page * | |
385 | nfs_create_subreq(struct nfs_page *req, struct nfs_page *last, | |
386 | unsigned int pgbase, unsigned int offset, | |
387 | unsigned int count) | |
388 | { | |
389 | struct nfs_page *ret; | |
390 | ||
28b1d3f5 | 391 | ret = __nfs_create_request(req->wb_lock_context, req->wb_page, |
c917cfaf TM |
392 | pgbase, offset, count); |
393 | if (!IS_ERR(ret)) { | |
394 | nfs_lock_request(ret); | |
395 | ret->wb_index = req->wb_index; | |
28b1d3f5 | 396 | nfs_page_group_init(ret, last); |
33344e0f | 397 | ret->wb_nio = req->wb_nio; |
c917cfaf TM |
398 | } |
399 | return ret; | |
400 | } | |
401 | ||
1da177e4 | 402 | /** |
1d1afcbc | 403 | * nfs_unlock_request - Unlock request and wake up sleepers. |
302fad7b | 404 | * @req: pointer to request |
1da177e4 | 405 | */ |
1d1afcbc | 406 | void nfs_unlock_request(struct nfs_page *req) |
1da177e4 LT |
407 | { |
408 | if (!NFS_WBACK_BUSY(req)) { | |
409 | printk(KERN_ERR "NFS: Invalid unlock attempted\n"); | |
410 | BUG(); | |
411 | } | |
4e857c58 | 412 | smp_mb__before_atomic(); |
1da177e4 | 413 | clear_bit(PG_BUSY, &req->wb_flags); |
4e857c58 | 414 | smp_mb__after_atomic(); |
b4f937cf TM |
415 | if (!test_bit(PG_CONTENDED2, &req->wb_flags)) |
416 | return; | |
464a98bd | 417 | wake_up_bit(&req->wb_flags, PG_BUSY); |
3aff4ebb TM |
418 | } |
419 | ||
420 | /** | |
1d1afcbc | 421 | * nfs_unlock_and_release_request - Unlock request and release the nfs_page |
302fad7b | 422 | * @req: pointer to request |
3aff4ebb | 423 | */ |
1d1afcbc | 424 | void nfs_unlock_and_release_request(struct nfs_page *req) |
3aff4ebb | 425 | { |
1d1afcbc | 426 | nfs_unlock_request(req); |
1da177e4 LT |
427 | nfs_release_request(req); |
428 | } | |
429 | ||
4d65c520 | 430 | /* |
1da177e4 LT |
431 | * nfs_clear_request - Free up all resources allocated to the request |
432 | * @req: | |
433 | * | |
bb6fbc45 TM |
434 | * Release page and open context resources associated with a read/write |
435 | * request after it has completed. | |
1da177e4 | 436 | */ |
4d65c520 | 437 | static void nfs_clear_request(struct nfs_page *req) |
1da177e4 | 438 | { |
cd52ed35 | 439 | struct page *page = req->wb_page; |
f11ac8db | 440 | struct nfs_lock_context *l_ctx = req->wb_lock_context; |
c79d183e | 441 | struct nfs_open_context *ctx; |
bb6fbc45 | 442 | |
cd52ed35 | 443 | if (page != NULL) { |
09cbfeaf | 444 | put_page(page); |
1da177e4 LT |
445 | req->wb_page = NULL; |
446 | } | |
f11ac8db | 447 | if (l_ctx != NULL) { |
7d6ddf88 | 448 | if (atomic_dec_and_test(&l_ctx->io_count)) { |
723c921e | 449 | wake_up_var(&l_ctx->io_count); |
c79d183e | 450 | ctx = l_ctx->open_context; |
7d6ddf88 BC |
451 | if (test_bit(NFS_CONTEXT_UNLOCK, &ctx->flags)) |
452 | rpc_wake_up(&NFS_SERVER(d_inode(ctx->dentry))->uoc_rpcwaitq); | |
453 | } | |
f11ac8db TM |
454 | nfs_put_lock_context(l_ctx); |
455 | req->wb_lock_context = NULL; | |
456 | } | |
1da177e4 LT |
457 | } |
458 | ||
1da177e4 LT |
459 | /** |
460 | * nfs_release_request - Release the count on an NFS read/write request | |
461 | * @req: request to release | |
462 | * | |
463 | * Note: Should never be called with the spinlock held! | |
464 | */ | |
d4581383 | 465 | void nfs_free_request(struct nfs_page *req) |
1da177e4 | 466 | { |
2bfc6e56 WAA |
467 | WARN_ON_ONCE(req->wb_this_page != req); |
468 | ||
469 | /* extra debug: make sure no sync bits are still set */ | |
470 | WARN_ON_ONCE(test_bit(PG_TEARDOWN, &req->wb_flags)); | |
67d0338e WAA |
471 | WARN_ON_ONCE(test_bit(PG_UNLOCKPAGE, &req->wb_flags)); |
472 | WARN_ON_ONCE(test_bit(PG_UPTODATE, &req->wb_flags)); | |
20633f04 WAA |
473 | WARN_ON_ONCE(test_bit(PG_WB_END, &req->wb_flags)); |
474 | WARN_ON_ONCE(test_bit(PG_REMOVE, &req->wb_flags)); | |
1da177e4 | 475 | |
bb6fbc45 | 476 | /* Release struct file and open context */ |
1da177e4 | 477 | nfs_clear_request(req); |
1da177e4 LT |
478 | nfs_page_free(req); |
479 | } | |
480 | ||
c03b4024 TM |
481 | void nfs_release_request(struct nfs_page *req) |
482 | { | |
2bfc6e56 | 483 | kref_put(&req->wb_kref, nfs_page_group_destroy); |
9f557cd8 | 484 | } |
2ce209c4 | 485 | EXPORT_SYMBOL_GPL(nfs_release_request); |
9f557cd8 | 486 | |
1da177e4 LT |
487 | /** |
488 | * nfs_wait_on_request - Wait for a request to complete. | |
489 | * @req: request to wait upon. | |
490 | * | |
150030b7 | 491 | * Interruptible by fatal signals only. |
1da177e4 LT |
492 | * The user is responsible for holding a count on the request. |
493 | */ | |
494 | int | |
495 | nfs_wait_on_request(struct nfs_page *req) | |
496 | { | |
b4f937cf TM |
497 | if (!test_bit(PG_BUSY, &req->wb_flags)) |
498 | return 0; | |
499 | set_bit(PG_CONTENDED2, &req->wb_flags); | |
500 | smp_mb__after_atomic(); | |
74316201 N |
501 | return wait_on_bit_io(&req->wb_flags, PG_BUSY, |
502 | TASK_UNINTERRUPTIBLE); | |
1da177e4 | 503 | } |
2ce209c4 | 504 | EXPORT_SYMBOL_GPL(nfs_wait_on_request); |
1da177e4 | 505 | |
b4fdac1a WAA |
506 | /* |
507 | * nfs_generic_pg_test - determine if requests can be coalesced | |
508 | * @desc: pointer to descriptor | |
509 | * @prev: previous request in desc, or NULL | |
510 | * @req: this request | |
511 | * | |
ac0aa5e8 | 512 | * Returns zero if @req cannot be coalesced into @desc, otherwise it returns |
b4fdac1a WAA |
513 | * the size of the request. |
514 | */ | |
515 | size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, | |
516 | struct nfs_page *prev, struct nfs_page *req) | |
5b36c7dc | 517 | { |
48d635f1 | 518 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb WAA |
519 | |
520 | ||
521 | if (mirror->pg_count > mirror->pg_bsize) { | |
f0cb9ab8 WAA |
522 | /* should never happen */ |
523 | WARN_ON_ONCE(1); | |
5b36c7dc | 524 | return 0; |
f0cb9ab8 | 525 | } |
5b36c7dc | 526 | |
2e11f829 CH |
527 | /* |
528 | * Limit the request size so that we can still allocate a page array | |
529 | * for it without upsetting the slab allocator. | |
530 | */ | |
a7d42ddb | 531 | if (((mirror->pg_count + req->wb_bytes) >> PAGE_SHIFT) * |
048883e0 | 532 | sizeof(struct page *) > PAGE_SIZE) |
2e11f829 CH |
533 | return 0; |
534 | ||
a7d42ddb | 535 | return min(mirror->pg_bsize - mirror->pg_count, (size_t)req->wb_bytes); |
5b36c7dc | 536 | } |
19345cb2 | 537 | EXPORT_SYMBOL_GPL(nfs_generic_pg_test); |
5b36c7dc | 538 | |
1e7f3a48 | 539 | struct nfs_pgio_header *nfs_pgio_header_alloc(const struct nfs_rw_ops *ops) |
4a0de55c | 540 | { |
1e7f3a48 | 541 | struct nfs_pgio_header *hdr = ops->rw_alloc_header(); |
4a0de55c | 542 | |
1e7f3a48 | 543 | if (hdr) { |
4a0de55c | 544 | INIT_LIST_HEAD(&hdr->pages); |
4a0de55c AS |
545 | hdr->rw_ops = ops; |
546 | } | |
1e7f3a48 | 547 | return hdr; |
4a0de55c | 548 | } |
1e7f3a48 | 549 | EXPORT_SYMBOL_GPL(nfs_pgio_header_alloc); |
4a0de55c | 550 | |
00bfa30a | 551 | /** |
4714fb51 WAA |
552 | * nfs_pgio_data_destroy - make @hdr suitable for reuse |
553 | * | |
554 | * Frees memory and releases refs from nfs_generic_pgio, so that it may | |
555 | * be called again. | |
556 | * | |
557 | * @hdr: A header that has had nfs_generic_pgio called | |
00bfa30a | 558 | */ |
196639eb | 559 | static void nfs_pgio_data_destroy(struct nfs_pgio_header *hdr) |
00bfa30a | 560 | { |
3caa0c6e TM |
561 | if (hdr->args.context) |
562 | put_nfs_open_context(hdr->args.context); | |
d45f60c6 WAA |
563 | if (hdr->page_array.pagevec != hdr->page_array.page_array) |
564 | kfree(hdr->page_array.pagevec); | |
00bfa30a | 565 | } |
196639eb TM |
566 | |
567 | /* | |
568 | * nfs_pgio_header_free - Free a read or write header | |
569 | * @hdr: The header to free | |
570 | */ | |
571 | void nfs_pgio_header_free(struct nfs_pgio_header *hdr) | |
572 | { | |
573 | nfs_pgio_data_destroy(hdr); | |
574 | hdr->rw_ops->rw_free_header(hdr); | |
575 | } | |
576 | EXPORT_SYMBOL_GPL(nfs_pgio_header_free); | |
00bfa30a | 577 | |
ce59515c AS |
578 | /** |
579 | * nfs_pgio_rpcsetup - Set up arguments for a pageio call | |
d45f60c6 | 580 | * @hdr: The pageio hdr |
ce59515c | 581 | * @count: Number of bytes to read |
ce59515c AS |
582 | * @how: How to commit data (writes only) |
583 | * @cinfo: Commit information for the call (writes only) | |
584 | */ | |
d45f60c6 | 585 | static void nfs_pgio_rpcsetup(struct nfs_pgio_header *hdr, |
e545735a | 586 | unsigned int count, |
ce59515c AS |
587 | int how, struct nfs_commit_info *cinfo) |
588 | { | |
d45f60c6 | 589 | struct nfs_page *req = hdr->req; |
ce59515c AS |
590 | |
591 | /* Set up the RPC argument and reply structs | |
d45f60c6 | 592 | * NB: take care not to mess about with hdr->commit et al. */ |
ce59515c | 593 | |
d45f60c6 | 594 | hdr->args.fh = NFS_FH(hdr->inode); |
e545735a | 595 | hdr->args.offset = req_offset(req); |
ce59515c | 596 | /* pnfs_set_layoutcommit needs this */ |
d45f60c6 | 597 | hdr->mds_offset = hdr->args.offset; |
e545735a | 598 | hdr->args.pgbase = req->wb_pgbase; |
d45f60c6 WAA |
599 | hdr->args.pages = hdr->page_array.pagevec; |
600 | hdr->args.count = count; | |
9fcd5960 | 601 | hdr->args.context = get_nfs_open_context(nfs_req_openctx(req)); |
d45f60c6 WAA |
602 | hdr->args.lock_context = req->wb_lock_context; |
603 | hdr->args.stable = NFS_UNSTABLE; | |
ce59515c AS |
604 | switch (how & (FLUSH_STABLE | FLUSH_COND_STABLE)) { |
605 | case 0: | |
606 | break; | |
607 | case FLUSH_COND_STABLE: | |
608 | if (nfs_reqs_to_commit(cinfo)) | |
609 | break; | |
01e03bdc | 610 | /* fall through */ |
ce59515c | 611 | default: |
d45f60c6 | 612 | hdr->args.stable = NFS_FILE_SYNC; |
ce59515c AS |
613 | } |
614 | ||
d45f60c6 | 615 | hdr->res.fattr = &hdr->fattr; |
17d8c5d1 | 616 | hdr->res.count = 0; |
d45f60c6 | 617 | hdr->res.eof = 0; |
c65e6254 | 618 | hdr->res.verf = &hdr->verf; |
d45f60c6 | 619 | nfs_fattr_init(&hdr->fattr); |
ce59515c AS |
620 | } |
621 | ||
a4cdda59 | 622 | /** |
d45f60c6 | 623 | * nfs_pgio_prepare - Prepare pageio hdr to go over the wire |
a4cdda59 | 624 | * @task: The current task |
d45f60c6 | 625 | * @calldata: pageio header to prepare |
a4cdda59 | 626 | */ |
6f92fa45 | 627 | static void nfs_pgio_prepare(struct rpc_task *task, void *calldata) |
a4cdda59 | 628 | { |
d45f60c6 | 629 | struct nfs_pgio_header *hdr = calldata; |
a4cdda59 | 630 | int err; |
d45f60c6 | 631 | err = NFS_PROTO(hdr->inode)->pgio_rpc_prepare(task, hdr); |
a4cdda59 AS |
632 | if (err) |
633 | rpc_exit(task, err); | |
634 | } | |
635 | ||
d45f60c6 | 636 | int nfs_initiate_pgio(struct rpc_clnt *clnt, struct nfs_pgio_header *hdr, |
a52458b4 | 637 | const struct cred *cred, const struct nfs_rpc_ops *rpc_ops, |
1ed26f33 AS |
638 | const struct rpc_call_ops *call_ops, int how, int flags) |
639 | { | |
640 | struct rpc_task *task; | |
641 | struct rpc_message msg = { | |
d45f60c6 WAA |
642 | .rpc_argp = &hdr->args, |
643 | .rpc_resp = &hdr->res, | |
46a5ab47 | 644 | .rpc_cred = cred, |
1ed26f33 AS |
645 | }; |
646 | struct rpc_task_setup task_setup_data = { | |
647 | .rpc_client = clnt, | |
d45f60c6 | 648 | .task = &hdr->task, |
1ed26f33 AS |
649 | .rpc_message = &msg, |
650 | .callback_ops = call_ops, | |
d45f60c6 | 651 | .callback_data = hdr, |
1ed26f33 AS |
652 | .workqueue = nfsiod_workqueue, |
653 | .flags = RPC_TASK_ASYNC | flags, | |
654 | }; | |
655 | int ret = 0; | |
656 | ||
abde71f4 | 657 | hdr->rw_ops->rw_initiate(hdr, &msg, rpc_ops, &task_setup_data, how); |
1ed26f33 | 658 | |
b4839ebe | 659 | dprintk("NFS: initiated pgio call " |
1ed26f33 | 660 | "(req %s/%llu, %u bytes @ offset %llu)\n", |
343ae531 AS |
661 | hdr->inode->i_sb->s_id, |
662 | (unsigned long long)NFS_FILEID(hdr->inode), | |
d45f60c6 WAA |
663 | hdr->args.count, |
664 | (unsigned long long)hdr->args.offset); | |
1ed26f33 AS |
665 | |
666 | task = rpc_run_task(&task_setup_data); | |
667 | if (IS_ERR(task)) { | |
668 | ret = PTR_ERR(task); | |
669 | goto out; | |
670 | } | |
671 | if (how & FLUSH_SYNC) { | |
672 | ret = rpc_wait_for_completion_task(task); | |
673 | if (ret == 0) | |
674 | ret = task->tk_status; | |
675 | } | |
676 | rpc_put_task(task); | |
677 | out: | |
678 | return ret; | |
679 | } | |
680 | EXPORT_SYMBOL_GPL(nfs_initiate_pgio); | |
681 | ||
844c9e69 AS |
682 | /** |
683 | * nfs_pgio_error - Clean up from a pageio error | |
844c9e69 AS |
684 | * @hdr: pageio header |
685 | */ | |
2bff2288 | 686 | static void nfs_pgio_error(struct nfs_pgio_header *hdr) |
844c9e69 | 687 | { |
844c9e69 | 688 | set_bit(NFS_IOHDR_REDO, &hdr->flags); |
4714fb51 | 689 | hdr->completion_ops->completion(hdr); |
844c9e69 AS |
690 | } |
691 | ||
a4cdda59 AS |
692 | /** |
693 | * nfs_pgio_release - Release pageio data | |
d45f60c6 | 694 | * @calldata: The pageio header to release |
a4cdda59 | 695 | */ |
6f92fa45 | 696 | static void nfs_pgio_release(void *calldata) |
a4cdda59 | 697 | { |
d45f60c6 | 698 | struct nfs_pgio_header *hdr = calldata; |
4714fb51 | 699 | hdr->completion_ops->completion(hdr); |
a4cdda59 AS |
700 | } |
701 | ||
a7d42ddb WAA |
702 | static void nfs_pageio_mirror_init(struct nfs_pgio_mirror *mirror, |
703 | unsigned int bsize) | |
704 | { | |
705 | INIT_LIST_HEAD(&mirror->pg_list); | |
706 | mirror->pg_bytes_written = 0; | |
707 | mirror->pg_count = 0; | |
708 | mirror->pg_bsize = bsize; | |
709 | mirror->pg_base = 0; | |
710 | mirror->pg_recoalesce = 0; | |
711 | } | |
712 | ||
1da177e4 | 713 | /** |
d8a5ad75 TM |
714 | * nfs_pageio_init - initialise a page io descriptor |
715 | * @desc: pointer to descriptor | |
bcb71bba | 716 | * @inode: pointer to inode |
dfad7000 YW |
717 | * @pg_ops: pointer to pageio operations |
718 | * @compl_ops: pointer to pageio completion operations | |
719 | * @rw_ops: pointer to nfs read/write operations | |
bcb71bba TM |
720 | * @bsize: io block size |
721 | * @io_flags: extra parameters for the io function | |
d8a5ad75 | 722 | */ |
bcb71bba TM |
723 | void nfs_pageio_init(struct nfs_pageio_descriptor *desc, |
724 | struct inode *inode, | |
1751c363 | 725 | const struct nfs_pageio_ops *pg_ops, |
061ae2ed | 726 | const struct nfs_pgio_completion_ops *compl_ops, |
4a0de55c | 727 | const struct nfs_rw_ops *rw_ops, |
84dde76c | 728 | size_t bsize, |
3bde7afd | 729 | int io_flags) |
d8a5ad75 | 730 | { |
b31268ac | 731 | desc->pg_moreio = 0; |
bcb71bba | 732 | desc->pg_inode = inode; |
1751c363 | 733 | desc->pg_ops = pg_ops; |
061ae2ed | 734 | desc->pg_completion_ops = compl_ops; |
4a0de55c | 735 | desc->pg_rw_ops = rw_ops; |
bcb71bba TM |
736 | desc->pg_ioflags = io_flags; |
737 | desc->pg_error = 0; | |
94ad1c80 | 738 | desc->pg_lseg = NULL; |
919e3bd9 | 739 | desc->pg_io_completion = NULL; |
584aa810 | 740 | desc->pg_dreq = NULL; |
a7d42ddb WAA |
741 | desc->pg_bsize = bsize; |
742 | ||
743 | desc->pg_mirror_count = 1; | |
744 | desc->pg_mirror_idx = 0; | |
745 | ||
14abcb0b TM |
746 | desc->pg_mirrors_dynamic = NULL; |
747 | desc->pg_mirrors = desc->pg_mirrors_static; | |
748 | nfs_pageio_mirror_init(&desc->pg_mirrors[0], bsize); | |
33344e0f | 749 | desc->pg_maxretrans = 0; |
d8a5ad75 TM |
750 | } |
751 | ||
0eecb214 AS |
752 | /** |
753 | * nfs_pgio_result - Basic pageio error handling | |
754 | * @task: The task that ran | |
d45f60c6 | 755 | * @calldata: Pageio header to check |
0eecb214 | 756 | */ |
6f92fa45 | 757 | static void nfs_pgio_result(struct rpc_task *task, void *calldata) |
0eecb214 | 758 | { |
d45f60c6 WAA |
759 | struct nfs_pgio_header *hdr = calldata; |
760 | struct inode *inode = hdr->inode; | |
0eecb214 AS |
761 | |
762 | dprintk("NFS: %s: %5u, (status %d)\n", __func__, | |
763 | task->tk_pid, task->tk_status); | |
764 | ||
d45f60c6 | 765 | if (hdr->rw_ops->rw_done(task, hdr, inode) != 0) |
0eecb214 AS |
766 | return; |
767 | if (task->tk_status < 0) | |
d45f60c6 | 768 | nfs_set_pgio_error(hdr, task->tk_status, hdr->args.offset); |
0eecb214 | 769 | else |
d45f60c6 | 770 | hdr->rw_ops->rw_result(task, hdr); |
0eecb214 AS |
771 | } |
772 | ||
ef2c488c AS |
773 | /* |
774 | * Create an RPC task for the given read or write request and kick it. | |
775 | * The page must have been locked by the caller. | |
776 | * | |
777 | * It may happen that the page we're passed is not marked dirty. | |
778 | * This is the case if nfs_updatepage detects a conflicting request | |
779 | * that has been written but not committed. | |
780 | */ | |
f0cb9ab8 WAA |
781 | int nfs_generic_pgio(struct nfs_pageio_descriptor *desc, |
782 | struct nfs_pgio_header *hdr) | |
ef2c488c | 783 | { |
48d635f1 | 784 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb | 785 | |
ef2c488c | 786 | struct nfs_page *req; |
bba5c188 WAA |
787 | struct page **pages, |
788 | *last_page; | |
a7d42ddb | 789 | struct list_head *head = &mirror->pg_list; |
ef2c488c | 790 | struct nfs_commit_info cinfo; |
8ef9b0b9 | 791 | struct nfs_page_array *pg_array = &hdr->page_array; |
bba5c188 | 792 | unsigned int pagecount, pageused; |
ae97aa52 | 793 | gfp_t gfp_flags = GFP_KERNEL; |
ef2c488c | 794 | |
a7d42ddb | 795 | pagecount = nfs_page_array_len(mirror->pg_base, mirror->pg_count); |
2eb3aea7 | 796 | pg_array->npages = pagecount; |
8ef9b0b9 BC |
797 | |
798 | if (pagecount <= ARRAY_SIZE(pg_array->page_array)) | |
799 | pg_array->pagevec = pg_array->page_array; | |
800 | else { | |
8ef9b0b9 BC |
801 | pg_array->pagevec = kcalloc(pagecount, sizeof(struct page *), gfp_flags); |
802 | if (!pg_array->pagevec) { | |
803 | pg_array->npages = 0; | |
804 | nfs_pgio_error(hdr); | |
805 | desc->pg_error = -ENOMEM; | |
806 | return desc->pg_error; | |
807 | } | |
2bff2288 | 808 | } |
ef2c488c AS |
809 | |
810 | nfs_init_cinfo(&cinfo, desc->pg_inode, desc->pg_dreq); | |
d45f60c6 | 811 | pages = hdr->page_array.pagevec; |
bba5c188 WAA |
812 | last_page = NULL; |
813 | pageused = 0; | |
ef2c488c AS |
814 | while (!list_empty(head)) { |
815 | req = nfs_list_entry(head->next); | |
078b5fd9 | 816 | nfs_list_move_request(req, &hdr->pages); |
bba5c188 | 817 | |
bba5c188 | 818 | if (!last_page || last_page != req->wb_page) { |
bba5c188 | 819 | pageused++; |
b8fb9c30 TM |
820 | if (pageused > pagecount) |
821 | break; | |
822 | *pages++ = last_page = req->wb_page; | |
bba5c188 | 823 | } |
ef2c488c | 824 | } |
2bff2288 PT |
825 | if (WARN_ON_ONCE(pageused != pagecount)) { |
826 | nfs_pgio_error(hdr); | |
827 | desc->pg_error = -EINVAL; | |
828 | return desc->pg_error; | |
829 | } | |
ef2c488c AS |
830 | |
831 | if ((desc->pg_ioflags & FLUSH_COND_STABLE) && | |
832 | (desc->pg_moreio || nfs_reqs_to_commit(&cinfo))) | |
833 | desc->pg_ioflags &= ~FLUSH_COND_STABLE; | |
834 | ||
835 | /* Set up the argument struct */ | |
e545735a | 836 | nfs_pgio_rpcsetup(hdr, mirror->pg_count, desc->pg_ioflags, &cinfo); |
ef2c488c AS |
837 | desc->pg_rpc_callops = &nfs_pgio_common_ops; |
838 | return 0; | |
839 | } | |
f0cb9ab8 | 840 | EXPORT_SYMBOL_GPL(nfs_generic_pgio); |
ef2c488c | 841 | |
41d8d5b7 | 842 | static int nfs_generic_pg_pgios(struct nfs_pageio_descriptor *desc) |
cf485fcd | 843 | { |
cf485fcd AS |
844 | struct nfs_pgio_header *hdr; |
845 | int ret; | |
846 | ||
1e7f3a48 WAA |
847 | hdr = nfs_pgio_header_alloc(desc->pg_rw_ops); |
848 | if (!hdr) { | |
2bff2288 PT |
849 | desc->pg_error = -ENOMEM; |
850 | return desc->pg_error; | |
cf485fcd | 851 | } |
1e7f3a48 | 852 | nfs_pgheader_init(desc, hdr, nfs_pgio_header_free); |
cf485fcd AS |
853 | ret = nfs_generic_pgio(desc, hdr); |
854 | if (ret == 0) | |
7f714720 | 855 | ret = nfs_initiate_pgio(NFS_CLIENT(hdr->inode), |
46a5ab47 PT |
856 | hdr, |
857 | hdr->cred, | |
858 | NFS_PROTO(hdr->inode), | |
abde71f4 | 859 | desc->pg_rpc_callops, |
7f714720 | 860 | desc->pg_ioflags, 0); |
cf485fcd AS |
861 | return ret; |
862 | } | |
863 | ||
14abcb0b TM |
864 | static struct nfs_pgio_mirror * |
865 | nfs_pageio_alloc_mirrors(struct nfs_pageio_descriptor *desc, | |
866 | unsigned int mirror_count) | |
867 | { | |
868 | struct nfs_pgio_mirror *ret; | |
869 | unsigned int i; | |
870 | ||
871 | kfree(desc->pg_mirrors_dynamic); | |
872 | desc->pg_mirrors_dynamic = NULL; | |
873 | if (mirror_count == 1) | |
874 | return desc->pg_mirrors_static; | |
2b17d725 | 875 | ret = kmalloc_array(mirror_count, sizeof(*ret), GFP_KERNEL); |
14abcb0b TM |
876 | if (ret != NULL) { |
877 | for (i = 0; i < mirror_count; i++) | |
878 | nfs_pageio_mirror_init(&ret[i], desc->pg_bsize); | |
879 | desc->pg_mirrors_dynamic = ret; | |
880 | } | |
881 | return ret; | |
882 | } | |
883 | ||
a7d42ddb WAA |
884 | /* |
885 | * nfs_pageio_setup_mirroring - determine if mirroring is to be used | |
886 | * by calling the pg_get_mirror_count op | |
887 | */ | |
14abcb0b | 888 | static void nfs_pageio_setup_mirroring(struct nfs_pageio_descriptor *pgio, |
a7d42ddb WAA |
889 | struct nfs_page *req) |
890 | { | |
14abcb0b | 891 | unsigned int mirror_count = 1; |
a7d42ddb | 892 | |
14abcb0b TM |
893 | if (pgio->pg_ops->pg_get_mirror_count) |
894 | mirror_count = pgio->pg_ops->pg_get_mirror_count(pgio, req); | |
895 | if (mirror_count == pgio->pg_mirror_count || pgio->pg_error < 0) | |
896 | return; | |
a7d42ddb | 897 | |
14abcb0b TM |
898 | if (!mirror_count || mirror_count > NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX) { |
899 | pgio->pg_error = -EINVAL; | |
900 | return; | |
901 | } | |
a7d42ddb | 902 | |
14abcb0b TM |
903 | pgio->pg_mirrors = nfs_pageio_alloc_mirrors(pgio, mirror_count); |
904 | if (pgio->pg_mirrors == NULL) { | |
905 | pgio->pg_error = -ENOMEM; | |
906 | pgio->pg_mirrors = pgio->pg_mirrors_static; | |
907 | mirror_count = 1; | |
908 | } | |
a7d42ddb | 909 | pgio->pg_mirror_count = mirror_count; |
a7d42ddb WAA |
910 | } |
911 | ||
a7d42ddb WAA |
912 | static void nfs_pageio_cleanup_mirroring(struct nfs_pageio_descriptor *pgio) |
913 | { | |
914 | pgio->pg_mirror_count = 1; | |
915 | pgio->pg_mirror_idx = 0; | |
916 | pgio->pg_mirrors = pgio->pg_mirrors_static; | |
917 | kfree(pgio->pg_mirrors_dynamic); | |
918 | pgio->pg_mirrors_dynamic = NULL; | |
919 | } | |
920 | ||
4109bb74 TM |
921 | static bool nfs_match_lock_context(const struct nfs_lock_context *l1, |
922 | const struct nfs_lock_context *l2) | |
923 | { | |
d51fdb87 | 924 | return l1->lockowner == l2->lockowner; |
4109bb74 TM |
925 | } |
926 | ||
d8a5ad75 TM |
927 | /** |
928 | * nfs_can_coalesce_requests - test two requests for compatibility | |
929 | * @prev: pointer to nfs_page | |
930 | * @req: pointer to nfs_page | |
302fad7b | 931 | * @pgio: pointer to nfs_pagio_descriptor |
d8a5ad75 TM |
932 | * |
933 | * The nfs_page structures 'prev' and 'req' are compared to ensure that the | |
934 | * page data area they describe is contiguous, and that their RPC | |
935 | * credentials, NFSv4 open state, and lockowners are the same. | |
936 | * | |
937 | * Return 'true' if this is the case, else return 'false'. | |
938 | */ | |
18ad0a9f BH |
939 | static bool nfs_can_coalesce_requests(struct nfs_page *prev, |
940 | struct nfs_page *req, | |
941 | struct nfs_pageio_descriptor *pgio) | |
d8a5ad75 | 942 | { |
b4fdac1a | 943 | size_t size; |
5263e31e | 944 | struct file_lock_context *flctx; |
b4fdac1a | 945 | |
ab75e417 | 946 | if (prev) { |
9fcd5960 | 947 | if (!nfs_match_open_context(nfs_req_openctx(req), nfs_req_openctx(prev))) |
ab75e417 | 948 | return false; |
9fcd5960 | 949 | flctx = d_inode(nfs_req_openctx(req)->dentry)->i_flctx; |
bd61e0a9 JL |
950 | if (flctx != NULL && |
951 | !(list_empty_careful(&flctx->flc_posix) && | |
952 | list_empty_careful(&flctx->flc_flock)) && | |
5263e31e JL |
953 | !nfs_match_lock_context(req->wb_lock_context, |
954 | prev->wb_lock_context)) | |
955 | return false; | |
ab75e417 WAA |
956 | if (req_offset(req) != req_offset(prev) + prev->wb_bytes) |
957 | return false; | |
78270e8f WAA |
958 | if (req->wb_page == prev->wb_page) { |
959 | if (req->wb_pgbase != prev->wb_pgbase + prev->wb_bytes) | |
960 | return false; | |
961 | } else { | |
962 | if (req->wb_pgbase != 0 || | |
09cbfeaf | 963 | prev->wb_pgbase + prev->wb_bytes != PAGE_SIZE) |
78270e8f WAA |
964 | return false; |
965 | } | |
ab75e417 | 966 | } |
b4fdac1a | 967 | size = pgio->pg_ops->pg_test(pgio, prev, req); |
f0cb9ab8 WAA |
968 | WARN_ON_ONCE(size > req->wb_bytes); |
969 | if (size && size < req->wb_bytes) | |
970 | req->wb_bytes = size; | |
b4fdac1a | 971 | return size > 0; |
d8a5ad75 TM |
972 | } |
973 | ||
974 | /** | |
bcb71bba | 975 | * nfs_pageio_do_add_request - Attempt to coalesce a request into a page list. |
d8a5ad75 TM |
976 | * @desc: destination io descriptor |
977 | * @req: request | |
978 | * | |
979 | * Returns true if the request 'req' was successfully coalesced into the | |
980 | * existing list of pages 'desc'. | |
981 | */ | |
bcb71bba TM |
982 | static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc, |
983 | struct nfs_page *req) | |
d8a5ad75 | 984 | { |
48d635f1 | 985 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb | 986 | |
ab75e417 | 987 | struct nfs_page *prev = NULL; |
a7d42ddb | 988 | |
a1f5ab56 | 989 | if (list_empty(&mirror->pg_list)) { |
d8007d4d TM |
990 | if (desc->pg_ops->pg_init) |
991 | desc->pg_ops->pg_init(desc, req); | |
d600ad1f PT |
992 | if (desc->pg_error < 0) |
993 | return 0; | |
a7d42ddb | 994 | mirror->pg_base = req->wb_pgbase; |
a1f5ab56 TM |
995 | mirror->pg_count = 0; |
996 | mirror->pg_recoalesce = 0; | |
997 | } else | |
998 | prev = nfs_list_entry(mirror->pg_list.prev); | |
33344e0f TM |
999 | |
1000 | if (desc->pg_maxretrans && req->wb_nio > desc->pg_maxretrans) { | |
1001 | if (NFS_SERVER(desc->pg_inode)->flags & NFS_MOUNT_SOFTERR) | |
1002 | desc->pg_error = -ETIMEDOUT; | |
1003 | else | |
1004 | desc->pg_error = -EIO; | |
1005 | return 0; | |
1006 | } | |
1007 | ||
ab75e417 WAA |
1008 | if (!nfs_can_coalesce_requests(prev, req, desc)) |
1009 | return 0; | |
078b5fd9 | 1010 | nfs_list_move_request(req, &mirror->pg_list); |
a7d42ddb | 1011 | mirror->pg_count += req->wb_bytes; |
d8a5ad75 TM |
1012 | return 1; |
1013 | } | |
1014 | ||
bcb71bba TM |
1015 | /* |
1016 | * Helper for nfs_pageio_add_request and nfs_pageio_complete | |
1017 | */ | |
1018 | static void nfs_pageio_doio(struct nfs_pageio_descriptor *desc) | |
1019 | { | |
48d635f1 | 1020 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb | 1021 | |
a7d42ddb | 1022 | if (!list_empty(&mirror->pg_list)) { |
1751c363 | 1023 | int error = desc->pg_ops->pg_doio(desc); |
bcb71bba TM |
1024 | if (error < 0) |
1025 | desc->pg_error = error; | |
cd2ce7fb | 1026 | if (list_empty(&mirror->pg_list)) { |
a7d42ddb | 1027 | mirror->pg_bytes_written += mirror->pg_count; |
cd2ce7fb TM |
1028 | mirror->pg_count = 0; |
1029 | mirror->pg_base = 0; | |
1030 | mirror->pg_recoalesce = 0; | |
1031 | } | |
bcb71bba TM |
1032 | } |
1033 | } | |
1034 | ||
f57dcf4c TM |
1035 | static void |
1036 | nfs_pageio_cleanup_request(struct nfs_pageio_descriptor *desc, | |
1037 | struct nfs_page *req) | |
1038 | { | |
1039 | LIST_HEAD(head); | |
1040 | ||
078b5fd9 | 1041 | nfs_list_move_request(req, &head); |
df3accb8 | 1042 | desc->pg_completion_ops->error_cleanup(&head, desc->pg_error); |
f57dcf4c TM |
1043 | } |
1044 | ||
bcb71bba TM |
1045 | /** |
1046 | * nfs_pageio_add_request - Attempt to coalesce a request into a page list. | |
1047 | * @desc: destination io descriptor | |
1048 | * @req: request | |
1049 | * | |
2bfc6e56 WAA |
1050 | * This may split a request into subrequests which are all part of the |
1051 | * same page group. | |
1052 | * | |
bcb71bba TM |
1053 | * Returns true if the request 'req' was successfully coalesced into the |
1054 | * existing list of pages 'desc'. | |
1055 | */ | |
d9156f9f | 1056 | static int __nfs_pageio_add_request(struct nfs_pageio_descriptor *desc, |
8b09bee3 | 1057 | struct nfs_page *req) |
bcb71bba | 1058 | { |
48d635f1 | 1059 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb | 1060 | |
2bfc6e56 WAA |
1061 | struct nfs_page *subreq; |
1062 | unsigned int bytes_left = 0; | |
1063 | unsigned int offset, pgbase; | |
1064 | ||
1344b7ea | 1065 | nfs_page_group_lock(req); |
2bfc6e56 WAA |
1066 | |
1067 | subreq = req; | |
1068 | bytes_left = subreq->wb_bytes; | |
1069 | offset = subreq->wb_offset; | |
1070 | pgbase = subreq->wb_pgbase; | |
1071 | ||
1072 | do { | |
1073 | if (!nfs_pageio_do_add_request(desc, subreq)) { | |
1074 | /* make sure pg_test call(s) did nothing */ | |
1075 | WARN_ON_ONCE(subreq->wb_bytes != bytes_left); | |
1076 | WARN_ON_ONCE(subreq->wb_offset != offset); | |
1077 | WARN_ON_ONCE(subreq->wb_pgbase != pgbase); | |
1078 | ||
1079 | nfs_page_group_unlock(req); | |
1080 | desc->pg_moreio = 1; | |
1081 | nfs_pageio_doio(desc); | |
f57dcf4c TM |
1082 | if (desc->pg_error < 0 || mirror->pg_recoalesce) |
1083 | goto out_cleanup_subreq; | |
2bfc6e56 | 1084 | /* retry add_request for this subreq */ |
1344b7ea | 1085 | nfs_page_group_lock(req); |
2bfc6e56 WAA |
1086 | continue; |
1087 | } | |
1088 | ||
1089 | /* check for buggy pg_test call(s) */ | |
1090 | WARN_ON_ONCE(subreq->wb_bytes + subreq->wb_pgbase > PAGE_SIZE); | |
1091 | WARN_ON_ONCE(subreq->wb_bytes > bytes_left); | |
1092 | WARN_ON_ONCE(subreq->wb_bytes == 0); | |
1093 | ||
1094 | bytes_left -= subreq->wb_bytes; | |
1095 | offset += subreq->wb_bytes; | |
1096 | pgbase += subreq->wb_bytes; | |
1097 | ||
1098 | if (bytes_left) { | |
c917cfaf TM |
1099 | subreq = nfs_create_subreq(req, subreq, pgbase, |
1100 | offset, bytes_left); | |
c1109558 TM |
1101 | if (IS_ERR(subreq)) |
1102 | goto err_ptr; | |
2bfc6e56 WAA |
1103 | } |
1104 | } while (bytes_left > 0); | |
1105 | ||
1106 | nfs_page_group_unlock(req); | |
bcb71bba | 1107 | return 1; |
c1109558 TM |
1108 | err_ptr: |
1109 | desc->pg_error = PTR_ERR(subreq); | |
1110 | nfs_page_group_unlock(req); | |
1111 | return 0; | |
f57dcf4c TM |
1112 | out_cleanup_subreq: |
1113 | if (req != subreq) | |
1114 | nfs_pageio_cleanup_request(desc, subreq); | |
1115 | return 0; | |
bcb71bba TM |
1116 | } |
1117 | ||
d9156f9f TM |
1118 | static int nfs_do_recoalesce(struct nfs_pageio_descriptor *desc) |
1119 | { | |
48d635f1 | 1120 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
d9156f9f TM |
1121 | LIST_HEAD(head); |
1122 | ||
1123 | do { | |
a7d42ddb | 1124 | list_splice_init(&mirror->pg_list, &head); |
a7d42ddb WAA |
1125 | mirror->pg_count = 0; |
1126 | mirror->pg_base = 0; | |
1127 | mirror->pg_recoalesce = 0; | |
1128 | ||
d9156f9f TM |
1129 | while (!list_empty(&head)) { |
1130 | struct nfs_page *req; | |
1131 | ||
1132 | req = list_first_entry(&head, struct nfs_page, wb_list); | |
d9156f9f TM |
1133 | if (__nfs_pageio_add_request(desc, req)) |
1134 | continue; | |
03d5eb65 TM |
1135 | if (desc->pg_error < 0) { |
1136 | list_splice_tail(&head, &mirror->pg_list); | |
1137 | mirror->pg_recoalesce = 1; | |
d9156f9f | 1138 | return 0; |
03d5eb65 | 1139 | } |
d9156f9f TM |
1140 | break; |
1141 | } | |
a7d42ddb | 1142 | } while (mirror->pg_recoalesce); |
d9156f9f TM |
1143 | return 1; |
1144 | } | |
1145 | ||
a7d42ddb | 1146 | static int nfs_pageio_add_request_mirror(struct nfs_pageio_descriptor *desc, |
d9156f9f TM |
1147 | struct nfs_page *req) |
1148 | { | |
1149 | int ret; | |
1150 | ||
1151 | do { | |
1152 | ret = __nfs_pageio_add_request(desc, req); | |
1153 | if (ret) | |
1154 | break; | |
1155 | if (desc->pg_error < 0) | |
1156 | break; | |
1157 | ret = nfs_do_recoalesce(desc); | |
1158 | } while (ret); | |
a7d42ddb | 1159 | |
d9156f9f TM |
1160 | return ret; |
1161 | } | |
1162 | ||
fdbd1a2e BC |
1163 | static void nfs_pageio_error_cleanup(struct nfs_pageio_descriptor *desc) |
1164 | { | |
1165 | u32 midx; | |
1166 | struct nfs_pgio_mirror *mirror; | |
1167 | ||
1168 | if (!desc->pg_error) | |
1169 | return; | |
1170 | ||
1171 | for (midx = 0; midx < desc->pg_mirror_count; midx++) { | |
1172 | mirror = &desc->pg_mirrors[midx]; | |
df3accb8 TM |
1173 | desc->pg_completion_ops->error_cleanup(&mirror->pg_list, |
1174 | desc->pg_error); | |
fdbd1a2e BC |
1175 | } |
1176 | } | |
1177 | ||
a7d42ddb WAA |
1178 | int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc, |
1179 | struct nfs_page *req) | |
1180 | { | |
1181 | u32 midx; | |
1182 | unsigned int pgbase, offset, bytes; | |
1183 | struct nfs_page *dupreq, *lastreq; | |
1184 | ||
1185 | pgbase = req->wb_pgbase; | |
1186 | offset = req->wb_offset; | |
1187 | bytes = req->wb_bytes; | |
1188 | ||
1189 | nfs_pageio_setup_mirroring(desc, req); | |
d600ad1f | 1190 | if (desc->pg_error < 0) |
c18b96a1 | 1191 | goto out_failed; |
a7d42ddb | 1192 | |
ae96b56f TM |
1193 | /* Create the mirror instances first, and fire them off */ |
1194 | for (midx = 1; midx < desc->pg_mirror_count; midx++) { | |
1195 | nfs_page_group_lock(req); | |
1196 | ||
1197 | /* find the last request */ | |
1198 | for (lastreq = req->wb_head; | |
1199 | lastreq->wb_this_page != req->wb_head; | |
1200 | lastreq = lastreq->wb_this_page) | |
1201 | ; | |
1202 | ||
1203 | dupreq = nfs_create_subreq(req, lastreq, | |
1204 | pgbase, offset, bytes); | |
1205 | ||
1206 | nfs_page_group_unlock(req); | |
1207 | if (IS_ERR(dupreq)) { | |
1208 | desc->pg_error = PTR_ERR(dupreq); | |
1209 | goto out_failed; | |
1210 | } | |
a7d42ddb | 1211 | |
ae96b56f | 1212 | desc->pg_mirror_idx = midx; |
a7d42ddb | 1213 | if (!nfs_pageio_add_request_mirror(desc, dupreq)) |
f57dcf4c | 1214 | goto out_cleanup_subreq; |
a7d42ddb WAA |
1215 | } |
1216 | ||
ae96b56f TM |
1217 | desc->pg_mirror_idx = 0; |
1218 | if (!nfs_pageio_add_request_mirror(desc, req)) | |
1219 | goto out_failed; | |
1220 | ||
a7d42ddb | 1221 | return 1; |
c18b96a1 | 1222 | |
f57dcf4c | 1223 | out_cleanup_subreq: |
ae96b56f | 1224 | nfs_pageio_cleanup_request(desc, dupreq); |
c18b96a1 | 1225 | out_failed: |
fdbd1a2e | 1226 | nfs_pageio_error_cleanup(desc); |
c18b96a1 | 1227 | return 0; |
a7d42ddb WAA |
1228 | } |
1229 | ||
1230 | /* | |
1231 | * nfs_pageio_complete_mirror - Complete I/O on the current mirror of an | |
1232 | * nfs_pageio_descriptor | |
1233 | * @desc: pointer to io descriptor | |
dfad7000 | 1234 | * @mirror_idx: pointer to mirror index |
a7d42ddb WAA |
1235 | */ |
1236 | static void nfs_pageio_complete_mirror(struct nfs_pageio_descriptor *desc, | |
1237 | u32 mirror_idx) | |
1238 | { | |
1239 | struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[mirror_idx]; | |
1240 | u32 restore_idx = desc->pg_mirror_idx; | |
1241 | ||
47af81f2 PT |
1242 | if (nfs_pgio_has_mirroring(desc)) |
1243 | desc->pg_mirror_idx = mirror_idx; | |
a7d42ddb WAA |
1244 | for (;;) { |
1245 | nfs_pageio_doio(desc); | |
8127d827 | 1246 | if (desc->pg_error < 0 || !mirror->pg_recoalesce) |
a7d42ddb WAA |
1247 | break; |
1248 | if (!nfs_do_recoalesce(desc)) | |
1249 | break; | |
1250 | } | |
1251 | desc->pg_mirror_idx = restore_idx; | |
1252 | } | |
1253 | ||
53113ad3 WAA |
1254 | /* |
1255 | * nfs_pageio_resend - Transfer requests to new descriptor and resend | |
1256 | * @hdr - the pgio header to move request from | |
1257 | * @desc - the pageio descriptor to add requests to | |
1258 | * | |
1259 | * Try to move each request (nfs_page) from @hdr to @desc then attempt | |
1260 | * to send them. | |
1261 | * | |
1262 | * Returns 0 on success and < 0 on error. | |
1263 | */ | |
1264 | int nfs_pageio_resend(struct nfs_pageio_descriptor *desc, | |
1265 | struct nfs_pgio_header *hdr) | |
1266 | { | |
f4340e93 | 1267 | LIST_HEAD(pages); |
53113ad3 | 1268 | |
919e3bd9 | 1269 | desc->pg_io_completion = hdr->io_completion; |
53113ad3 | 1270 | desc->pg_dreq = hdr->dreq; |
f4340e93 TM |
1271 | list_splice_init(&hdr->pages, &pages); |
1272 | while (!list_empty(&pages)) { | |
1273 | struct nfs_page *req = nfs_list_entry(pages.next); | |
53113ad3 | 1274 | |
53113ad3 | 1275 | if (!nfs_pageio_add_request(desc, req)) |
f4340e93 | 1276 | break; |
53113ad3 WAA |
1277 | } |
1278 | nfs_pageio_complete(desc); | |
f4340e93 TM |
1279 | if (!list_empty(&pages)) { |
1280 | int err = desc->pg_error < 0 ? desc->pg_error : -EIO; | |
1281 | hdr->completion_ops->error_cleanup(&pages, err); | |
eb2c50da | 1282 | nfs_set_pgio_error(hdr, err, hdr->io_start); |
f4340e93 | 1283 | return err; |
53113ad3 WAA |
1284 | } |
1285 | return 0; | |
1286 | } | |
1287 | EXPORT_SYMBOL_GPL(nfs_pageio_resend); | |
d9156f9f | 1288 | |
bcb71bba | 1289 | /** |
2176bf42 | 1290 | * nfs_pageio_complete - Complete I/O then cleanup an nfs_pageio_descriptor |
bcb71bba TM |
1291 | * @desc: pointer to io descriptor |
1292 | */ | |
1293 | void nfs_pageio_complete(struct nfs_pageio_descriptor *desc) | |
1294 | { | |
a7d42ddb WAA |
1295 | u32 midx; |
1296 | ||
1297 | for (midx = 0; midx < desc->pg_mirror_count; midx++) | |
1298 | nfs_pageio_complete_mirror(desc, midx); | |
2176bf42 | 1299 | |
fdbd1a2e BC |
1300 | if (desc->pg_error < 0) |
1301 | nfs_pageio_error_cleanup(desc); | |
2176bf42 WAA |
1302 | if (desc->pg_ops->pg_cleanup) |
1303 | desc->pg_ops->pg_cleanup(desc); | |
a7d42ddb | 1304 | nfs_pageio_cleanup_mirroring(desc); |
bcb71bba TM |
1305 | } |
1306 | ||
7fe7f848 TM |
1307 | /** |
1308 | * nfs_pageio_cond_complete - Conditional I/O completion | |
1309 | * @desc: pointer to io descriptor | |
1310 | * @index: page index | |
1311 | * | |
1312 | * It is important to ensure that processes don't try to take locks | |
1313 | * on non-contiguous ranges of pages as that might deadlock. This | |
1314 | * function should be called before attempting to wait on a locked | |
1315 | * nfs_page. It will complete the I/O if the page index 'index' | |
1316 | * is not contiguous with the existing list of pages in 'desc'. | |
1317 | */ | |
1318 | void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *desc, pgoff_t index) | |
1319 | { | |
a7d42ddb WAA |
1320 | struct nfs_pgio_mirror *mirror; |
1321 | struct nfs_page *prev; | |
1322 | u32 midx; | |
1323 | ||
1324 | for (midx = 0; midx < desc->pg_mirror_count; midx++) { | |
1325 | mirror = &desc->pg_mirrors[midx]; | |
1326 | if (!list_empty(&mirror->pg_list)) { | |
1327 | prev = nfs_list_entry(mirror->pg_list.prev); | |
43b7d964 BC |
1328 | if (index != prev->wb_index + 1) { |
1329 | nfs_pageio_complete(desc); | |
1330 | break; | |
1331 | } | |
a7d42ddb | 1332 | } |
7fe7f848 TM |
1333 | } |
1334 | } | |
1335 | ||
e3e8cd13 TM |
1336 | /* |
1337 | * nfs_pageio_stop_mirroring - stop using mirroring (set mirror count to 1) | |
1338 | */ | |
1339 | void nfs_pageio_stop_mirroring(struct nfs_pageio_descriptor *pgio) | |
1340 | { | |
1341 | nfs_pageio_complete(pgio); | |
1342 | } | |
1343 | ||
f7b422b1 | 1344 | int __init nfs_init_nfspagecache(void) |
1da177e4 LT |
1345 | { |
1346 | nfs_page_cachep = kmem_cache_create("nfs_page", | |
1347 | sizeof(struct nfs_page), | |
1348 | 0, SLAB_HWCACHE_ALIGN, | |
20c2df83 | 1349 | NULL); |
1da177e4 LT |
1350 | if (nfs_page_cachep == NULL) |
1351 | return -ENOMEM; | |
1352 | ||
1353 | return 0; | |
1354 | } | |
1355 | ||
266bee88 | 1356 | void nfs_destroy_nfspagecache(void) |
1da177e4 | 1357 | { |
1a1d92c1 | 1358 | kmem_cache_destroy(nfs_page_cachep); |
1da177e4 LT |
1359 | } |
1360 | ||
ef2c488c | 1361 | static const struct rpc_call_ops nfs_pgio_common_ops = { |
6f92fa45 AS |
1362 | .rpc_call_prepare = nfs_pgio_prepare, |
1363 | .rpc_call_done = nfs_pgio_result, | |
1364 | .rpc_release = nfs_pgio_release, | |
1365 | }; | |
41d8d5b7 AS |
1366 | |
1367 | const struct nfs_pageio_ops nfs_pgio_rw_ops = { | |
1368 | .pg_test = nfs_generic_pg_test, | |
1369 | .pg_doio = nfs_generic_pg_pgios, | |
1370 | }; |