Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/nfs/pagelist.c | |
3 | * | |
4 | * A set of helper functions for managing NFS read and write requests. | |
5 | * The main purpose of these routines is to provide support for the | |
6 | * coalescing of several requests into a single RPC call. | |
7 | * | |
8 | * Copyright 2000, 2001 (c) Trond Myklebust <trond.myklebust@fys.uio.no> | |
9 | * | |
10 | */ | |
11 | ||
1da177e4 LT |
12 | #include <linux/slab.h> |
13 | #include <linux/file.h> | |
e8edc6e0 | 14 | #include <linux/sched.h> |
1da177e4 | 15 | #include <linux/sunrpc/clnt.h> |
1313e603 | 16 | #include <linux/nfs.h> |
1da177e4 LT |
17 | #include <linux/nfs3.h> |
18 | #include <linux/nfs4.h> | |
19 | #include <linux/nfs_page.h> | |
20 | #include <linux/nfs_fs.h> | |
21 | #include <linux/nfs_mount.h> | |
afeacc8c | 22 | #include <linux/export.h> |
1da177e4 | 23 | |
8d5658c9 | 24 | #include "internal.h" |
bae724ef | 25 | #include "pnfs.h" |
8d5658c9 | 26 | |
0eecb214 AS |
27 | #define NFSDBG_FACILITY NFSDBG_PAGECACHE |
28 | ||
e18b890b | 29 | static struct kmem_cache *nfs_page_cachep; |
ef2c488c | 30 | static const struct rpc_call_ops nfs_pgio_common_ops; |
1da177e4 | 31 | |
00bfa30a | 32 | static bool nfs_pgarray_set(struct nfs_page_array *p, unsigned int pagecount) |
30dd374f FI |
33 | { |
34 | p->npages = pagecount; | |
35 | if (pagecount <= ARRAY_SIZE(p->page_array)) | |
36 | p->pagevec = p->page_array; | |
37 | else { | |
38 | p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_KERNEL); | |
39 | if (!p->pagevec) | |
40 | p->npages = 0; | |
41 | } | |
42 | return p->pagevec != NULL; | |
43 | } | |
44 | ||
48d635f1 PT |
45 | struct nfs_pgio_mirror * |
46 | nfs_pgio_current_mirror(struct nfs_pageio_descriptor *desc) | |
47 | { | |
48 | return nfs_pgio_has_mirroring(desc) ? | |
49 | &desc->pg_mirrors[desc->pg_mirror_idx] : | |
50 | &desc->pg_mirrors[0]; | |
51 | } | |
52 | EXPORT_SYMBOL_GPL(nfs_pgio_current_mirror); | |
53 | ||
4db6e0b7 FI |
54 | void nfs_pgheader_init(struct nfs_pageio_descriptor *desc, |
55 | struct nfs_pgio_header *hdr, | |
56 | void (*release)(struct nfs_pgio_header *hdr)) | |
57 | { | |
48d635f1 | 58 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb WAA |
59 | |
60 | ||
61 | hdr->req = nfs_list_entry(mirror->pg_list.next); | |
4db6e0b7 FI |
62 | hdr->inode = desc->pg_inode; |
63 | hdr->cred = hdr->req->wb_context->cred; | |
64 | hdr->io_start = req_offset(hdr->req); | |
a7d42ddb | 65 | hdr->good_bytes = mirror->pg_count; |
584aa810 | 66 | hdr->dreq = desc->pg_dreq; |
f6166384 | 67 | hdr->layout_private = desc->pg_layout_private; |
4db6e0b7 | 68 | hdr->release = release; |
061ae2ed | 69 | hdr->completion_ops = desc->pg_completion_ops; |
584aa810 FI |
70 | if (hdr->completion_ops->init_hdr) |
71 | hdr->completion_ops->init_hdr(hdr); | |
a7d42ddb WAA |
72 | |
73 | hdr->pgio_mirror_idx = desc->pg_mirror_idx; | |
4db6e0b7 | 74 | } |
89d77c8f | 75 | EXPORT_SYMBOL_GPL(nfs_pgheader_init); |
4db6e0b7 FI |
76 | |
77 | void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos) | |
78 | { | |
79 | spin_lock(&hdr->lock); | |
e9ae58ae TM |
80 | if (!test_and_set_bit(NFS_IOHDR_ERROR, &hdr->flags) |
81 | || pos < hdr->io_start + hdr->good_bytes) { | |
4db6e0b7 FI |
82 | clear_bit(NFS_IOHDR_EOF, &hdr->flags); |
83 | hdr->good_bytes = pos - hdr->io_start; | |
84 | hdr->error = error; | |
85 | } | |
86 | spin_unlock(&hdr->lock); | |
87 | } | |
88 | ||
1da177e4 LT |
89 | static inline struct nfs_page * |
90 | nfs_page_alloc(void) | |
91 | { | |
192e501b | 92 | struct nfs_page *p = kmem_cache_zalloc(nfs_page_cachep, GFP_NOIO); |
72895b1a | 93 | if (p) |
1da177e4 | 94 | INIT_LIST_HEAD(&p->wb_list); |
1da177e4 LT |
95 | return p; |
96 | } | |
97 | ||
98 | static inline void | |
99 | nfs_page_free(struct nfs_page *p) | |
100 | { | |
101 | kmem_cache_free(nfs_page_cachep, p); | |
102 | } | |
103 | ||
577b4232 TM |
104 | /** |
105 | * nfs_iocounter_wait - wait for i/o to complete | |
210c7c17 | 106 | * @l_ctx: nfs_lock_context with io_counter to use |
577b4232 TM |
107 | * |
108 | * returns -ERESTARTSYS if interrupted by a fatal signal. | |
109 | * Otherwise returns 0 once the io_count hits 0. | |
110 | */ | |
111 | int | |
210c7c17 | 112 | nfs_iocounter_wait(struct nfs_lock_context *l_ctx) |
577b4232 | 113 | { |
210c7c17 BC |
114 | return wait_on_atomic_t(&l_ctx->io_count, nfs_wait_atomic_killable, |
115 | TASK_KILLABLE); | |
577b4232 TM |
116 | } |
117 | ||
2bfc6e56 WAA |
118 | /* |
119 | * nfs_page_group_lock - lock the head of the page group | |
120 | * @req - request in group that is to be locked | |
fd2f3a06 | 121 | * @nonblock - if true don't block waiting for lock |
2bfc6e56 WAA |
122 | * |
123 | * this lock must be held if modifying the page group list | |
e7029206 | 124 | * |
bc8a309e WAA |
125 | * return 0 on success, < 0 on error: -EDELAY if nonblocking or the |
126 | * result from wait_on_bit_lock | |
127 | * | |
128 | * NOTE: calling with nonblock=false should always have set the | |
129 | * lock bit (see fs/buffer.c and other uses of wait_on_bit_lock | |
130 | * with TASK_UNINTERRUPTIBLE), so there is no need to check the result. | |
2bfc6e56 | 131 | */ |
e7029206 | 132 | int |
fd2f3a06 | 133 | nfs_page_group_lock(struct nfs_page *req, bool nonblock) |
2bfc6e56 WAA |
134 | { |
135 | struct nfs_page *head = req->wb_head; | |
2bfc6e56 WAA |
136 | |
137 | WARN_ON_ONCE(head != head->wb_head); | |
138 | ||
bc8a309e WAA |
139 | if (!test_and_set_bit(PG_HEADLOCK, &head->wb_flags)) |
140 | return 0; | |
e7029206 | 141 | |
bc8a309e WAA |
142 | if (!nonblock) |
143 | return wait_on_bit_lock(&head->wb_flags, PG_HEADLOCK, | |
144 | TASK_UNINTERRUPTIBLE); | |
145 | ||
146 | return -EAGAIN; | |
2bfc6e56 WAA |
147 | } |
148 | ||
7c3af975 WAA |
149 | /* |
150 | * nfs_page_group_lock_wait - wait for the lock to clear, but don't grab it | |
151 | * @req - a request in the group | |
152 | * | |
153 | * This is a blocking call to wait for the group lock to be cleared. | |
154 | */ | |
155 | void | |
156 | nfs_page_group_lock_wait(struct nfs_page *req) | |
157 | { | |
158 | struct nfs_page *head = req->wb_head; | |
159 | ||
160 | WARN_ON_ONCE(head != head->wb_head); | |
161 | ||
162 | wait_on_bit(&head->wb_flags, PG_HEADLOCK, | |
163 | TASK_UNINTERRUPTIBLE); | |
164 | } | |
165 | ||
2bfc6e56 WAA |
166 | /* |
167 | * nfs_page_group_unlock - unlock the head of the page group | |
168 | * @req - request in group that is to be unlocked | |
169 | */ | |
170 | void | |
171 | nfs_page_group_unlock(struct nfs_page *req) | |
172 | { | |
173 | struct nfs_page *head = req->wb_head; | |
174 | ||
175 | WARN_ON_ONCE(head != head->wb_head); | |
176 | ||
d1e1cda8 | 177 | smp_mb__before_atomic(); |
2bfc6e56 | 178 | clear_bit(PG_HEADLOCK, &head->wb_flags); |
d1e1cda8 | 179 | smp_mb__after_atomic(); |
2bfc6e56 WAA |
180 | wake_up_bit(&head->wb_flags, PG_HEADLOCK); |
181 | } | |
182 | ||
183 | /* | |
184 | * nfs_page_group_sync_on_bit_locked | |
185 | * | |
186 | * must be called with page group lock held | |
187 | */ | |
188 | static bool | |
189 | nfs_page_group_sync_on_bit_locked(struct nfs_page *req, unsigned int bit) | |
190 | { | |
191 | struct nfs_page *head = req->wb_head; | |
192 | struct nfs_page *tmp; | |
193 | ||
194 | WARN_ON_ONCE(!test_bit(PG_HEADLOCK, &head->wb_flags)); | |
195 | WARN_ON_ONCE(test_and_set_bit(bit, &req->wb_flags)); | |
196 | ||
197 | tmp = req->wb_this_page; | |
198 | while (tmp != req) { | |
199 | if (!test_bit(bit, &tmp->wb_flags)) | |
200 | return false; | |
201 | tmp = tmp->wb_this_page; | |
202 | } | |
203 | ||
204 | /* true! reset all bits */ | |
205 | tmp = req; | |
206 | do { | |
207 | clear_bit(bit, &tmp->wb_flags); | |
208 | tmp = tmp->wb_this_page; | |
209 | } while (tmp != req); | |
210 | ||
211 | return true; | |
212 | } | |
213 | ||
214 | /* | |
215 | * nfs_page_group_sync_on_bit - set bit on current request, but only | |
216 | * return true if the bit is set for all requests in page group | |
217 | * @req - request in page group | |
218 | * @bit - PG_* bit that is used to sync page group | |
219 | */ | |
220 | bool nfs_page_group_sync_on_bit(struct nfs_page *req, unsigned int bit) | |
221 | { | |
222 | bool ret; | |
223 | ||
fd2f3a06 | 224 | nfs_page_group_lock(req, false); |
2bfc6e56 WAA |
225 | ret = nfs_page_group_sync_on_bit_locked(req, bit); |
226 | nfs_page_group_unlock(req); | |
227 | ||
228 | return ret; | |
229 | } | |
230 | ||
231 | /* | |
232 | * nfs_page_group_init - Initialize the page group linkage for @req | |
233 | * @req - a new nfs request | |
234 | * @prev - the previous request in page group, or NULL if @req is the first | |
235 | * or only request in the group (the head). | |
236 | */ | |
237 | static inline void | |
238 | nfs_page_group_init(struct nfs_page *req, struct nfs_page *prev) | |
239 | { | |
cb1410c7 | 240 | struct inode *inode; |
2bfc6e56 WAA |
241 | WARN_ON_ONCE(prev == req); |
242 | ||
243 | if (!prev) { | |
85710a83 | 244 | /* a head request */ |
2bfc6e56 WAA |
245 | req->wb_head = req; |
246 | req->wb_this_page = req; | |
247 | } else { | |
85710a83 | 248 | /* a subrequest */ |
2bfc6e56 WAA |
249 | WARN_ON_ONCE(prev->wb_this_page != prev->wb_head); |
250 | WARN_ON_ONCE(!test_bit(PG_HEADLOCK, &prev->wb_head->wb_flags)); | |
251 | req->wb_head = prev->wb_head; | |
252 | req->wb_this_page = prev->wb_this_page; | |
253 | prev->wb_this_page = req; | |
254 | ||
85710a83 WAA |
255 | /* All subrequests take a ref on the head request until |
256 | * nfs_page_group_destroy is called */ | |
257 | kref_get(&req->wb_head->wb_kref); | |
258 | ||
cb1410c7 WAA |
259 | /* grab extra ref and bump the request count if head request |
260 | * has extra ref from the write/commit path to handle handoff | |
261 | * between write and commit lists. */ | |
17089a29 | 262 | if (test_bit(PG_INODE_REF, &prev->wb_head->wb_flags)) { |
cb1410c7 | 263 | inode = page_file_mapping(req->wb_page)->host; |
17089a29 | 264 | set_bit(PG_INODE_REF, &req->wb_flags); |
2bfc6e56 | 265 | kref_get(&req->wb_kref); |
cb1410c7 WAA |
266 | spin_lock(&inode->i_lock); |
267 | NFS_I(inode)->nrequests++; | |
268 | spin_unlock(&inode->i_lock); | |
17089a29 | 269 | } |
2bfc6e56 WAA |
270 | } |
271 | } | |
272 | ||
273 | /* | |
274 | * nfs_page_group_destroy - sync the destruction of page groups | |
275 | * @req - request that no longer needs the page group | |
276 | * | |
277 | * releases the page group reference from each member once all | |
278 | * members have called this function. | |
279 | */ | |
280 | static void | |
281 | nfs_page_group_destroy(struct kref *kref) | |
282 | { | |
283 | struct nfs_page *req = container_of(kref, struct nfs_page, wb_kref); | |
284 | struct nfs_page *tmp, *next; | |
285 | ||
85710a83 WAA |
286 | /* subrequests must release the ref on the head request */ |
287 | if (req->wb_head != req) | |
288 | nfs_release_request(req->wb_head); | |
289 | ||
2bfc6e56 WAA |
290 | if (!nfs_page_group_sync_on_bit(req, PG_TEARDOWN)) |
291 | return; | |
292 | ||
293 | tmp = req; | |
294 | do { | |
295 | next = tmp->wb_this_page; | |
296 | /* unlink and free */ | |
297 | tmp->wb_this_page = tmp; | |
298 | tmp->wb_head = tmp; | |
299 | nfs_free_request(tmp); | |
300 | tmp = next; | |
301 | } while (tmp != req); | |
302 | } | |
303 | ||
1da177e4 LT |
304 | /** |
305 | * nfs_create_request - Create an NFS read/write request. | |
c02f557d | 306 | * @ctx: open context to use |
1da177e4 | 307 | * @page: page to write |
2bfc6e56 | 308 | * @last: last nfs request created for this page group or NULL if head |
1da177e4 LT |
309 | * @offset: starting offset within the page for the write |
310 | * @count: number of bytes to read/write | |
311 | * | |
312 | * The page must be locked by the caller. This makes sure we never | |
a19b89ca | 313 | * create two different requests for the same page. |
1da177e4 LT |
314 | * User should ensure it is safe to sleep in this function. |
315 | */ | |
316 | struct nfs_page * | |
8c8f1ac1 | 317 | nfs_create_request(struct nfs_open_context *ctx, struct page *page, |
2bfc6e56 WAA |
318 | struct nfs_page *last, unsigned int offset, |
319 | unsigned int count) | |
1da177e4 | 320 | { |
1da177e4 | 321 | struct nfs_page *req; |
b3c54de6 | 322 | struct nfs_lock_context *l_ctx; |
1da177e4 | 323 | |
c58c8441 TM |
324 | if (test_bit(NFS_CONTEXT_BAD, &ctx->flags)) |
325 | return ERR_PTR(-EBADF); | |
18eb8842 TM |
326 | /* try to allocate the request struct */ |
327 | req = nfs_page_alloc(); | |
328 | if (req == NULL) | |
329 | return ERR_PTR(-ENOMEM); | |
1da177e4 | 330 | |
015f0212 | 331 | /* get lock context early so we can deal with alloc failures */ |
b3c54de6 TM |
332 | l_ctx = nfs_get_lock_context(ctx); |
333 | if (IS_ERR(l_ctx)) { | |
015f0212 | 334 | nfs_page_free(req); |
b3c54de6 | 335 | return ERR_CAST(l_ctx); |
015f0212 | 336 | } |
b3c54de6 | 337 | req->wb_lock_context = l_ctx; |
210c7c17 | 338 | atomic_inc(&l_ctx->io_count); |
015f0212 | 339 | |
1da177e4 LT |
340 | /* Initialize the request struct. Initially, we assume a |
341 | * long write-back delay. This will be adjusted in | |
342 | * update_nfs_request below if the region is not locked. */ | |
343 | req->wb_page = page; | |
d56b4ddf | 344 | req->wb_index = page_file_index(page); |
1da177e4 LT |
345 | page_cache_get(page); |
346 | req->wb_offset = offset; | |
347 | req->wb_pgbase = offset; | |
348 | req->wb_bytes = count; | |
1da177e4 | 349 | req->wb_context = get_nfs_open_context(ctx); |
c03b4024 | 350 | kref_init(&req->wb_kref); |
2bfc6e56 | 351 | nfs_page_group_init(req, last); |
1da177e4 LT |
352 | return req; |
353 | } | |
354 | ||
355 | /** | |
1d1afcbc | 356 | * nfs_unlock_request - Unlock request and wake up sleepers. |
1da177e4 LT |
357 | * @req: |
358 | */ | |
1d1afcbc | 359 | void nfs_unlock_request(struct nfs_page *req) |
1da177e4 LT |
360 | { |
361 | if (!NFS_WBACK_BUSY(req)) { | |
362 | printk(KERN_ERR "NFS: Invalid unlock attempted\n"); | |
363 | BUG(); | |
364 | } | |
4e857c58 | 365 | smp_mb__before_atomic(); |
1da177e4 | 366 | clear_bit(PG_BUSY, &req->wb_flags); |
4e857c58 | 367 | smp_mb__after_atomic(); |
464a98bd | 368 | wake_up_bit(&req->wb_flags, PG_BUSY); |
3aff4ebb TM |
369 | } |
370 | ||
371 | /** | |
1d1afcbc TM |
372 | * nfs_unlock_and_release_request - Unlock request and release the nfs_page |
373 | * @req: | |
3aff4ebb | 374 | */ |
1d1afcbc | 375 | void nfs_unlock_and_release_request(struct nfs_page *req) |
3aff4ebb | 376 | { |
1d1afcbc | 377 | nfs_unlock_request(req); |
1da177e4 LT |
378 | nfs_release_request(req); |
379 | } | |
380 | ||
4d65c520 | 381 | /* |
1da177e4 LT |
382 | * nfs_clear_request - Free up all resources allocated to the request |
383 | * @req: | |
384 | * | |
bb6fbc45 TM |
385 | * Release page and open context resources associated with a read/write |
386 | * request after it has completed. | |
1da177e4 | 387 | */ |
4d65c520 | 388 | static void nfs_clear_request(struct nfs_page *req) |
1da177e4 | 389 | { |
cd52ed35 | 390 | struct page *page = req->wb_page; |
bb6fbc45 | 391 | struct nfs_open_context *ctx = req->wb_context; |
f11ac8db | 392 | struct nfs_lock_context *l_ctx = req->wb_lock_context; |
bb6fbc45 | 393 | |
cd52ed35 | 394 | if (page != NULL) { |
cd52ed35 | 395 | page_cache_release(page); |
1da177e4 LT |
396 | req->wb_page = NULL; |
397 | } | |
f11ac8db | 398 | if (l_ctx != NULL) { |
210c7c17 BC |
399 | if (atomic_dec_and_test(&l_ctx->io_count)) |
400 | wake_up_atomic_t(&l_ctx->io_count); | |
f11ac8db TM |
401 | nfs_put_lock_context(l_ctx); |
402 | req->wb_lock_context = NULL; | |
403 | } | |
bb6fbc45 TM |
404 | if (ctx != NULL) { |
405 | put_nfs_open_context(ctx); | |
406 | req->wb_context = NULL; | |
407 | } | |
1da177e4 LT |
408 | } |
409 | ||
1da177e4 LT |
410 | /** |
411 | * nfs_release_request - Release the count on an NFS read/write request | |
412 | * @req: request to release | |
413 | * | |
414 | * Note: Should never be called with the spinlock held! | |
415 | */ | |
d4581383 | 416 | void nfs_free_request(struct nfs_page *req) |
1da177e4 | 417 | { |
2bfc6e56 WAA |
418 | WARN_ON_ONCE(req->wb_this_page != req); |
419 | ||
420 | /* extra debug: make sure no sync bits are still set */ | |
421 | WARN_ON_ONCE(test_bit(PG_TEARDOWN, &req->wb_flags)); | |
67d0338e WAA |
422 | WARN_ON_ONCE(test_bit(PG_UNLOCKPAGE, &req->wb_flags)); |
423 | WARN_ON_ONCE(test_bit(PG_UPTODATE, &req->wb_flags)); | |
20633f04 WAA |
424 | WARN_ON_ONCE(test_bit(PG_WB_END, &req->wb_flags)); |
425 | WARN_ON_ONCE(test_bit(PG_REMOVE, &req->wb_flags)); | |
1da177e4 | 426 | |
bb6fbc45 | 427 | /* Release struct file and open context */ |
1da177e4 | 428 | nfs_clear_request(req); |
1da177e4 LT |
429 | nfs_page_free(req); |
430 | } | |
431 | ||
c03b4024 TM |
432 | void nfs_release_request(struct nfs_page *req) |
433 | { | |
2bfc6e56 | 434 | kref_put(&req->wb_kref, nfs_page_group_destroy); |
9f557cd8 TM |
435 | } |
436 | ||
1da177e4 LT |
437 | /** |
438 | * nfs_wait_on_request - Wait for a request to complete. | |
439 | * @req: request to wait upon. | |
440 | * | |
150030b7 | 441 | * Interruptible by fatal signals only. |
1da177e4 LT |
442 | * The user is responsible for holding a count on the request. |
443 | */ | |
444 | int | |
445 | nfs_wait_on_request(struct nfs_page *req) | |
446 | { | |
74316201 N |
447 | return wait_on_bit_io(&req->wb_flags, PG_BUSY, |
448 | TASK_UNINTERRUPTIBLE); | |
1da177e4 LT |
449 | } |
450 | ||
b4fdac1a WAA |
451 | /* |
452 | * nfs_generic_pg_test - determine if requests can be coalesced | |
453 | * @desc: pointer to descriptor | |
454 | * @prev: previous request in desc, or NULL | |
455 | * @req: this request | |
456 | * | |
457 | * Returns zero if @req can be coalesced into @desc, otherwise it returns | |
458 | * the size of the request. | |
459 | */ | |
460 | size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, | |
461 | struct nfs_page *prev, struct nfs_page *req) | |
5b36c7dc | 462 | { |
48d635f1 | 463 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb WAA |
464 | |
465 | ||
466 | if (mirror->pg_count > mirror->pg_bsize) { | |
f0cb9ab8 WAA |
467 | /* should never happen */ |
468 | WARN_ON_ONCE(1); | |
5b36c7dc | 469 | return 0; |
f0cb9ab8 | 470 | } |
5b36c7dc | 471 | |
2e11f829 CH |
472 | /* |
473 | * Limit the request size so that we can still allocate a page array | |
474 | * for it without upsetting the slab allocator. | |
475 | */ | |
a7d42ddb | 476 | if (((mirror->pg_count + req->wb_bytes) >> PAGE_SHIFT) * |
048883e0 | 477 | sizeof(struct page *) > PAGE_SIZE) |
2e11f829 CH |
478 | return 0; |
479 | ||
a7d42ddb | 480 | return min(mirror->pg_bsize - mirror->pg_count, (size_t)req->wb_bytes); |
5b36c7dc | 481 | } |
19345cb2 | 482 | EXPORT_SYMBOL_GPL(nfs_generic_pg_test); |
5b36c7dc | 483 | |
1e7f3a48 | 484 | struct nfs_pgio_header *nfs_pgio_header_alloc(const struct nfs_rw_ops *ops) |
4a0de55c | 485 | { |
1e7f3a48 | 486 | struct nfs_pgio_header *hdr = ops->rw_alloc_header(); |
4a0de55c | 487 | |
1e7f3a48 | 488 | if (hdr) { |
4a0de55c | 489 | INIT_LIST_HEAD(&hdr->pages); |
4a0de55c | 490 | spin_lock_init(&hdr->lock); |
4a0de55c AS |
491 | hdr->rw_ops = ops; |
492 | } | |
1e7f3a48 | 493 | return hdr; |
4a0de55c | 494 | } |
1e7f3a48 | 495 | EXPORT_SYMBOL_GPL(nfs_pgio_header_alloc); |
4a0de55c AS |
496 | |
497 | /* | |
1e7f3a48 | 498 | * nfs_pgio_header_free - Free a read or write header |
4a0de55c AS |
499 | * @hdr: The header to free |
500 | */ | |
1e7f3a48 | 501 | void nfs_pgio_header_free(struct nfs_pgio_header *hdr) |
4a0de55c | 502 | { |
1e7f3a48 | 503 | hdr->rw_ops->rw_free_header(hdr); |
4a0de55c | 504 | } |
1e7f3a48 | 505 | EXPORT_SYMBOL_GPL(nfs_pgio_header_free); |
4a0de55c | 506 | |
00bfa30a | 507 | /** |
4714fb51 WAA |
508 | * nfs_pgio_data_destroy - make @hdr suitable for reuse |
509 | * | |
510 | * Frees memory and releases refs from nfs_generic_pgio, so that it may | |
511 | * be called again. | |
512 | * | |
513 | * @hdr: A header that has had nfs_generic_pgio called | |
00bfa30a | 514 | */ |
d45f60c6 | 515 | void nfs_pgio_data_destroy(struct nfs_pgio_header *hdr) |
00bfa30a | 516 | { |
3caa0c6e TM |
517 | if (hdr->args.context) |
518 | put_nfs_open_context(hdr->args.context); | |
d45f60c6 WAA |
519 | if (hdr->page_array.pagevec != hdr->page_array.page_array) |
520 | kfree(hdr->page_array.pagevec); | |
00bfa30a | 521 | } |
1e7f3a48 | 522 | EXPORT_SYMBOL_GPL(nfs_pgio_data_destroy); |
00bfa30a | 523 | |
ce59515c AS |
524 | /** |
525 | * nfs_pgio_rpcsetup - Set up arguments for a pageio call | |
d45f60c6 | 526 | * @hdr: The pageio hdr |
ce59515c AS |
527 | * @count: Number of bytes to read |
528 | * @offset: Initial offset | |
529 | * @how: How to commit data (writes only) | |
530 | * @cinfo: Commit information for the call (writes only) | |
531 | */ | |
d45f60c6 | 532 | static void nfs_pgio_rpcsetup(struct nfs_pgio_header *hdr, |
ce59515c AS |
533 | unsigned int count, unsigned int offset, |
534 | int how, struct nfs_commit_info *cinfo) | |
535 | { | |
d45f60c6 | 536 | struct nfs_page *req = hdr->req; |
ce59515c AS |
537 | |
538 | /* Set up the RPC argument and reply structs | |
d45f60c6 | 539 | * NB: take care not to mess about with hdr->commit et al. */ |
ce59515c | 540 | |
d45f60c6 WAA |
541 | hdr->args.fh = NFS_FH(hdr->inode); |
542 | hdr->args.offset = req_offset(req) + offset; | |
ce59515c | 543 | /* pnfs_set_layoutcommit needs this */ |
d45f60c6 WAA |
544 | hdr->mds_offset = hdr->args.offset; |
545 | hdr->args.pgbase = req->wb_pgbase + offset; | |
546 | hdr->args.pages = hdr->page_array.pagevec; | |
547 | hdr->args.count = count; | |
548 | hdr->args.context = get_nfs_open_context(req->wb_context); | |
549 | hdr->args.lock_context = req->wb_lock_context; | |
550 | hdr->args.stable = NFS_UNSTABLE; | |
ce59515c AS |
551 | switch (how & (FLUSH_STABLE | FLUSH_COND_STABLE)) { |
552 | case 0: | |
553 | break; | |
554 | case FLUSH_COND_STABLE: | |
555 | if (nfs_reqs_to_commit(cinfo)) | |
556 | break; | |
557 | default: | |
d45f60c6 | 558 | hdr->args.stable = NFS_FILE_SYNC; |
ce59515c AS |
559 | } |
560 | ||
d45f60c6 WAA |
561 | hdr->res.fattr = &hdr->fattr; |
562 | hdr->res.count = count; | |
563 | hdr->res.eof = 0; | |
c65e6254 | 564 | hdr->res.verf = &hdr->verf; |
d45f60c6 | 565 | nfs_fattr_init(&hdr->fattr); |
ce59515c AS |
566 | } |
567 | ||
a4cdda59 | 568 | /** |
d45f60c6 | 569 | * nfs_pgio_prepare - Prepare pageio hdr to go over the wire |
a4cdda59 | 570 | * @task: The current task |
d45f60c6 | 571 | * @calldata: pageio header to prepare |
a4cdda59 | 572 | */ |
6f92fa45 | 573 | static void nfs_pgio_prepare(struct rpc_task *task, void *calldata) |
a4cdda59 | 574 | { |
d45f60c6 | 575 | struct nfs_pgio_header *hdr = calldata; |
a4cdda59 | 576 | int err; |
d45f60c6 | 577 | err = NFS_PROTO(hdr->inode)->pgio_rpc_prepare(task, hdr); |
a4cdda59 AS |
578 | if (err) |
579 | rpc_exit(task, err); | |
580 | } | |
581 | ||
d45f60c6 | 582 | int nfs_initiate_pgio(struct rpc_clnt *clnt, struct nfs_pgio_header *hdr, |
46a5ab47 | 583 | struct rpc_cred *cred, const struct nfs_rpc_ops *rpc_ops, |
1ed26f33 AS |
584 | const struct rpc_call_ops *call_ops, int how, int flags) |
585 | { | |
586 | struct rpc_task *task; | |
587 | struct rpc_message msg = { | |
d45f60c6 WAA |
588 | .rpc_argp = &hdr->args, |
589 | .rpc_resp = &hdr->res, | |
46a5ab47 | 590 | .rpc_cred = cred, |
1ed26f33 AS |
591 | }; |
592 | struct rpc_task_setup task_setup_data = { | |
593 | .rpc_client = clnt, | |
d45f60c6 | 594 | .task = &hdr->task, |
1ed26f33 AS |
595 | .rpc_message = &msg, |
596 | .callback_ops = call_ops, | |
d45f60c6 | 597 | .callback_data = hdr, |
1ed26f33 AS |
598 | .workqueue = nfsiod_workqueue, |
599 | .flags = RPC_TASK_ASYNC | flags, | |
600 | }; | |
601 | int ret = 0; | |
602 | ||
abde71f4 | 603 | hdr->rw_ops->rw_initiate(hdr, &msg, rpc_ops, &task_setup_data, how); |
1ed26f33 | 604 | |
b4839ebe | 605 | dprintk("NFS: initiated pgio call " |
1ed26f33 | 606 | "(req %s/%llu, %u bytes @ offset %llu)\n", |
343ae531 AS |
607 | hdr->inode->i_sb->s_id, |
608 | (unsigned long long)NFS_FILEID(hdr->inode), | |
d45f60c6 WAA |
609 | hdr->args.count, |
610 | (unsigned long long)hdr->args.offset); | |
1ed26f33 AS |
611 | |
612 | task = rpc_run_task(&task_setup_data); | |
613 | if (IS_ERR(task)) { | |
614 | ret = PTR_ERR(task); | |
615 | goto out; | |
616 | } | |
617 | if (how & FLUSH_SYNC) { | |
618 | ret = rpc_wait_for_completion_task(task); | |
619 | if (ret == 0) | |
620 | ret = task->tk_status; | |
621 | } | |
622 | rpc_put_task(task); | |
623 | out: | |
624 | return ret; | |
625 | } | |
626 | EXPORT_SYMBOL_GPL(nfs_initiate_pgio); | |
627 | ||
844c9e69 AS |
628 | /** |
629 | * nfs_pgio_error - Clean up from a pageio error | |
630 | * @desc: IO descriptor | |
631 | * @hdr: pageio header | |
632 | */ | |
2bff2288 | 633 | static void nfs_pgio_error(struct nfs_pgio_header *hdr) |
844c9e69 | 634 | { |
844c9e69 | 635 | set_bit(NFS_IOHDR_REDO, &hdr->flags); |
d45f60c6 | 636 | nfs_pgio_data_destroy(hdr); |
4714fb51 | 637 | hdr->completion_ops->completion(hdr); |
844c9e69 AS |
638 | } |
639 | ||
a4cdda59 AS |
640 | /** |
641 | * nfs_pgio_release - Release pageio data | |
d45f60c6 | 642 | * @calldata: The pageio header to release |
a4cdda59 | 643 | */ |
6f92fa45 | 644 | static void nfs_pgio_release(void *calldata) |
a4cdda59 | 645 | { |
d45f60c6 | 646 | struct nfs_pgio_header *hdr = calldata; |
d45f60c6 | 647 | nfs_pgio_data_destroy(hdr); |
4714fb51 | 648 | hdr->completion_ops->completion(hdr); |
a4cdda59 AS |
649 | } |
650 | ||
a7d42ddb WAA |
651 | static void nfs_pageio_mirror_init(struct nfs_pgio_mirror *mirror, |
652 | unsigned int bsize) | |
653 | { | |
654 | INIT_LIST_HEAD(&mirror->pg_list); | |
655 | mirror->pg_bytes_written = 0; | |
656 | mirror->pg_count = 0; | |
657 | mirror->pg_bsize = bsize; | |
658 | mirror->pg_base = 0; | |
659 | mirror->pg_recoalesce = 0; | |
660 | } | |
661 | ||
1da177e4 | 662 | /** |
d8a5ad75 TM |
663 | * nfs_pageio_init - initialise a page io descriptor |
664 | * @desc: pointer to descriptor | |
bcb71bba | 665 | * @inode: pointer to inode |
dfad7000 YW |
666 | * @pg_ops: pointer to pageio operations |
667 | * @compl_ops: pointer to pageio completion operations | |
668 | * @rw_ops: pointer to nfs read/write operations | |
bcb71bba TM |
669 | * @bsize: io block size |
670 | * @io_flags: extra parameters for the io function | |
d8a5ad75 | 671 | */ |
bcb71bba TM |
672 | void nfs_pageio_init(struct nfs_pageio_descriptor *desc, |
673 | struct inode *inode, | |
1751c363 | 674 | const struct nfs_pageio_ops *pg_ops, |
061ae2ed | 675 | const struct nfs_pgio_completion_ops *compl_ops, |
4a0de55c | 676 | const struct nfs_rw_ops *rw_ops, |
84dde76c | 677 | size_t bsize, |
bcb71bba | 678 | int io_flags) |
d8a5ad75 | 679 | { |
a7d42ddb WAA |
680 | struct nfs_pgio_mirror *new; |
681 | int i; | |
682 | ||
b31268ac | 683 | desc->pg_moreio = 0; |
bcb71bba | 684 | desc->pg_inode = inode; |
1751c363 | 685 | desc->pg_ops = pg_ops; |
061ae2ed | 686 | desc->pg_completion_ops = compl_ops; |
4a0de55c | 687 | desc->pg_rw_ops = rw_ops; |
bcb71bba TM |
688 | desc->pg_ioflags = io_flags; |
689 | desc->pg_error = 0; | |
94ad1c80 | 690 | desc->pg_lseg = NULL; |
584aa810 | 691 | desc->pg_dreq = NULL; |
f6166384 | 692 | desc->pg_layout_private = NULL; |
a7d42ddb WAA |
693 | desc->pg_bsize = bsize; |
694 | ||
695 | desc->pg_mirror_count = 1; | |
696 | desc->pg_mirror_idx = 0; | |
697 | ||
698 | if (pg_ops->pg_get_mirror_count) { | |
699 | /* until we have a request, we don't have an lseg and no | |
700 | * idea how many mirrors there will be */ | |
701 | new = kcalloc(NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX, | |
702 | sizeof(struct nfs_pgio_mirror), GFP_KERNEL); | |
703 | desc->pg_mirrors_dynamic = new; | |
704 | desc->pg_mirrors = new; | |
705 | ||
706 | for (i = 0; i < NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX; i++) | |
707 | nfs_pageio_mirror_init(&desc->pg_mirrors[i], bsize); | |
708 | } else { | |
709 | desc->pg_mirrors_dynamic = NULL; | |
710 | desc->pg_mirrors = desc->pg_mirrors_static; | |
711 | nfs_pageio_mirror_init(&desc->pg_mirrors[0], bsize); | |
712 | } | |
d8a5ad75 | 713 | } |
89d77c8f | 714 | EXPORT_SYMBOL_GPL(nfs_pageio_init); |
d8a5ad75 | 715 | |
0eecb214 AS |
716 | /** |
717 | * nfs_pgio_result - Basic pageio error handling | |
718 | * @task: The task that ran | |
d45f60c6 | 719 | * @calldata: Pageio header to check |
0eecb214 | 720 | */ |
6f92fa45 | 721 | static void nfs_pgio_result(struct rpc_task *task, void *calldata) |
0eecb214 | 722 | { |
d45f60c6 WAA |
723 | struct nfs_pgio_header *hdr = calldata; |
724 | struct inode *inode = hdr->inode; | |
0eecb214 AS |
725 | |
726 | dprintk("NFS: %s: %5u, (status %d)\n", __func__, | |
727 | task->tk_pid, task->tk_status); | |
728 | ||
d45f60c6 | 729 | if (hdr->rw_ops->rw_done(task, hdr, inode) != 0) |
0eecb214 AS |
730 | return; |
731 | if (task->tk_status < 0) | |
d45f60c6 | 732 | nfs_set_pgio_error(hdr, task->tk_status, hdr->args.offset); |
0eecb214 | 733 | else |
d45f60c6 | 734 | hdr->rw_ops->rw_result(task, hdr); |
0eecb214 AS |
735 | } |
736 | ||
ef2c488c AS |
737 | /* |
738 | * Create an RPC task for the given read or write request and kick it. | |
739 | * The page must have been locked by the caller. | |
740 | * | |
741 | * It may happen that the page we're passed is not marked dirty. | |
742 | * This is the case if nfs_updatepage detects a conflicting request | |
743 | * that has been written but not committed. | |
744 | */ | |
f0cb9ab8 WAA |
745 | int nfs_generic_pgio(struct nfs_pageio_descriptor *desc, |
746 | struct nfs_pgio_header *hdr) | |
ef2c488c | 747 | { |
48d635f1 | 748 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb | 749 | |
ef2c488c | 750 | struct nfs_page *req; |
bba5c188 WAA |
751 | struct page **pages, |
752 | *last_page; | |
a7d42ddb | 753 | struct list_head *head = &mirror->pg_list; |
ef2c488c | 754 | struct nfs_commit_info cinfo; |
bba5c188 | 755 | unsigned int pagecount, pageused; |
ef2c488c | 756 | |
a7d42ddb | 757 | pagecount = nfs_page_array_len(mirror->pg_base, mirror->pg_count); |
2bff2288 PT |
758 | if (!nfs_pgarray_set(&hdr->page_array, pagecount)) { |
759 | nfs_pgio_error(hdr); | |
760 | desc->pg_error = -ENOMEM; | |
761 | return desc->pg_error; | |
762 | } | |
ef2c488c AS |
763 | |
764 | nfs_init_cinfo(&cinfo, desc->pg_inode, desc->pg_dreq); | |
d45f60c6 | 765 | pages = hdr->page_array.pagevec; |
bba5c188 WAA |
766 | last_page = NULL; |
767 | pageused = 0; | |
ef2c488c AS |
768 | while (!list_empty(head)) { |
769 | req = nfs_list_entry(head->next); | |
770 | nfs_list_remove_request(req); | |
771 | nfs_list_add_request(req, &hdr->pages); | |
bba5c188 | 772 | |
bba5c188 | 773 | if (!last_page || last_page != req->wb_page) { |
bba5c188 | 774 | pageused++; |
b8fb9c30 TM |
775 | if (pageused > pagecount) |
776 | break; | |
777 | *pages++ = last_page = req->wb_page; | |
bba5c188 | 778 | } |
ef2c488c | 779 | } |
2bff2288 PT |
780 | if (WARN_ON_ONCE(pageused != pagecount)) { |
781 | nfs_pgio_error(hdr); | |
782 | desc->pg_error = -EINVAL; | |
783 | return desc->pg_error; | |
784 | } | |
ef2c488c AS |
785 | |
786 | if ((desc->pg_ioflags & FLUSH_COND_STABLE) && | |
787 | (desc->pg_moreio || nfs_reqs_to_commit(&cinfo))) | |
788 | desc->pg_ioflags &= ~FLUSH_COND_STABLE; | |
789 | ||
790 | /* Set up the argument struct */ | |
a7d42ddb | 791 | nfs_pgio_rpcsetup(hdr, mirror->pg_count, 0, desc->pg_ioflags, &cinfo); |
ef2c488c AS |
792 | desc->pg_rpc_callops = &nfs_pgio_common_ops; |
793 | return 0; | |
794 | } | |
f0cb9ab8 | 795 | EXPORT_SYMBOL_GPL(nfs_generic_pgio); |
ef2c488c | 796 | |
41d8d5b7 | 797 | static int nfs_generic_pg_pgios(struct nfs_pageio_descriptor *desc) |
cf485fcd | 798 | { |
cf485fcd AS |
799 | struct nfs_pgio_header *hdr; |
800 | int ret; | |
801 | ||
1e7f3a48 WAA |
802 | hdr = nfs_pgio_header_alloc(desc->pg_rw_ops); |
803 | if (!hdr) { | |
2bff2288 PT |
804 | desc->pg_error = -ENOMEM; |
805 | return desc->pg_error; | |
cf485fcd | 806 | } |
1e7f3a48 | 807 | nfs_pgheader_init(desc, hdr, nfs_pgio_header_free); |
cf485fcd AS |
808 | ret = nfs_generic_pgio(desc, hdr); |
809 | if (ret == 0) | |
7f714720 | 810 | ret = nfs_initiate_pgio(NFS_CLIENT(hdr->inode), |
46a5ab47 PT |
811 | hdr, |
812 | hdr->cred, | |
813 | NFS_PROTO(hdr->inode), | |
abde71f4 | 814 | desc->pg_rpc_callops, |
7f714720 | 815 | desc->pg_ioflags, 0); |
cf485fcd AS |
816 | return ret; |
817 | } | |
818 | ||
a7d42ddb WAA |
819 | /* |
820 | * nfs_pageio_setup_mirroring - determine if mirroring is to be used | |
821 | * by calling the pg_get_mirror_count op | |
822 | */ | |
823 | static int nfs_pageio_setup_mirroring(struct nfs_pageio_descriptor *pgio, | |
824 | struct nfs_page *req) | |
825 | { | |
826 | int mirror_count = 1; | |
827 | ||
828 | if (!pgio->pg_ops->pg_get_mirror_count) | |
829 | return 0; | |
830 | ||
831 | mirror_count = pgio->pg_ops->pg_get_mirror_count(pgio, req); | |
832 | ||
d600ad1f PT |
833 | if (pgio->pg_error < 0) |
834 | return pgio->pg_error; | |
835 | ||
a7d42ddb WAA |
836 | if (!mirror_count || mirror_count > NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX) |
837 | return -EINVAL; | |
838 | ||
839 | if (WARN_ON_ONCE(!pgio->pg_mirrors_dynamic)) | |
840 | return -EINVAL; | |
841 | ||
842 | pgio->pg_mirror_count = mirror_count; | |
843 | ||
844 | return 0; | |
845 | } | |
846 | ||
847 | /* | |
848 | * nfs_pageio_stop_mirroring - stop using mirroring (set mirror count to 1) | |
849 | */ | |
850 | void nfs_pageio_stop_mirroring(struct nfs_pageio_descriptor *pgio) | |
851 | { | |
852 | pgio->pg_mirror_count = 1; | |
853 | pgio->pg_mirror_idx = 0; | |
854 | } | |
855 | ||
856 | static void nfs_pageio_cleanup_mirroring(struct nfs_pageio_descriptor *pgio) | |
857 | { | |
858 | pgio->pg_mirror_count = 1; | |
859 | pgio->pg_mirror_idx = 0; | |
860 | pgio->pg_mirrors = pgio->pg_mirrors_static; | |
861 | kfree(pgio->pg_mirrors_dynamic); | |
862 | pgio->pg_mirrors_dynamic = NULL; | |
863 | } | |
864 | ||
4109bb74 TM |
865 | static bool nfs_match_lock_context(const struct nfs_lock_context *l1, |
866 | const struct nfs_lock_context *l2) | |
867 | { | |
868 | return l1->lockowner.l_owner == l2->lockowner.l_owner | |
869 | && l1->lockowner.l_pid == l2->lockowner.l_pid; | |
870 | } | |
871 | ||
d8a5ad75 TM |
872 | /** |
873 | * nfs_can_coalesce_requests - test two requests for compatibility | |
874 | * @prev: pointer to nfs_page | |
875 | * @req: pointer to nfs_page | |
876 | * | |
877 | * The nfs_page structures 'prev' and 'req' are compared to ensure that the | |
878 | * page data area they describe is contiguous, and that their RPC | |
879 | * credentials, NFSv4 open state, and lockowners are the same. | |
880 | * | |
881 | * Return 'true' if this is the case, else return 'false'. | |
882 | */ | |
18ad0a9f BH |
883 | static bool nfs_can_coalesce_requests(struct nfs_page *prev, |
884 | struct nfs_page *req, | |
885 | struct nfs_pageio_descriptor *pgio) | |
d8a5ad75 | 886 | { |
b4fdac1a | 887 | size_t size; |
5263e31e | 888 | struct file_lock_context *flctx; |
b4fdac1a | 889 | |
ab75e417 WAA |
890 | if (prev) { |
891 | if (!nfs_match_open_context(req->wb_context, prev->wb_context)) | |
892 | return false; | |
2b0143b5 | 893 | flctx = d_inode(req->wb_context->dentry)->i_flctx; |
bd61e0a9 JL |
894 | if (flctx != NULL && |
895 | !(list_empty_careful(&flctx->flc_posix) && | |
896 | list_empty_careful(&flctx->flc_flock)) && | |
5263e31e JL |
897 | !nfs_match_lock_context(req->wb_lock_context, |
898 | prev->wb_lock_context)) | |
899 | return false; | |
ab75e417 WAA |
900 | if (req_offset(req) != req_offset(prev) + prev->wb_bytes) |
901 | return false; | |
78270e8f WAA |
902 | if (req->wb_page == prev->wb_page) { |
903 | if (req->wb_pgbase != prev->wb_pgbase + prev->wb_bytes) | |
904 | return false; | |
905 | } else { | |
906 | if (req->wb_pgbase != 0 || | |
907 | prev->wb_pgbase + prev->wb_bytes != PAGE_CACHE_SIZE) | |
908 | return false; | |
909 | } | |
ab75e417 | 910 | } |
b4fdac1a | 911 | size = pgio->pg_ops->pg_test(pgio, prev, req); |
f0cb9ab8 WAA |
912 | WARN_ON_ONCE(size > req->wb_bytes); |
913 | if (size && size < req->wb_bytes) | |
914 | req->wb_bytes = size; | |
b4fdac1a | 915 | return size > 0; |
d8a5ad75 TM |
916 | } |
917 | ||
918 | /** | |
bcb71bba | 919 | * nfs_pageio_do_add_request - Attempt to coalesce a request into a page list. |
d8a5ad75 TM |
920 | * @desc: destination io descriptor |
921 | * @req: request | |
922 | * | |
923 | * Returns true if the request 'req' was successfully coalesced into the | |
924 | * existing list of pages 'desc'. | |
925 | */ | |
bcb71bba TM |
926 | static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc, |
927 | struct nfs_page *req) | |
d8a5ad75 | 928 | { |
48d635f1 | 929 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb | 930 | |
ab75e417 | 931 | struct nfs_page *prev = NULL; |
a7d42ddb WAA |
932 | |
933 | if (mirror->pg_count != 0) { | |
934 | prev = nfs_list_entry(mirror->pg_list.prev); | |
5b36c7dc | 935 | } else { |
d8007d4d TM |
936 | if (desc->pg_ops->pg_init) |
937 | desc->pg_ops->pg_init(desc, req); | |
d600ad1f PT |
938 | if (desc->pg_error < 0) |
939 | return 0; | |
a7d42ddb | 940 | mirror->pg_base = req->wb_pgbase; |
5b36c7dc | 941 | } |
ab75e417 WAA |
942 | if (!nfs_can_coalesce_requests(prev, req, desc)) |
943 | return 0; | |
d8a5ad75 | 944 | nfs_list_remove_request(req); |
a7d42ddb WAA |
945 | nfs_list_add_request(req, &mirror->pg_list); |
946 | mirror->pg_count += req->wb_bytes; | |
d8a5ad75 TM |
947 | return 1; |
948 | } | |
949 | ||
bcb71bba TM |
950 | /* |
951 | * Helper for nfs_pageio_add_request and nfs_pageio_complete | |
952 | */ | |
953 | static void nfs_pageio_doio(struct nfs_pageio_descriptor *desc) | |
954 | { | |
48d635f1 | 955 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb WAA |
956 | |
957 | ||
958 | if (!list_empty(&mirror->pg_list)) { | |
1751c363 | 959 | int error = desc->pg_ops->pg_doio(desc); |
bcb71bba TM |
960 | if (error < 0) |
961 | desc->pg_error = error; | |
962 | else | |
a7d42ddb | 963 | mirror->pg_bytes_written += mirror->pg_count; |
bcb71bba | 964 | } |
a7d42ddb WAA |
965 | if (list_empty(&mirror->pg_list)) { |
966 | mirror->pg_count = 0; | |
967 | mirror->pg_base = 0; | |
bcb71bba TM |
968 | } |
969 | } | |
970 | ||
971 | /** | |
972 | * nfs_pageio_add_request - Attempt to coalesce a request into a page list. | |
973 | * @desc: destination io descriptor | |
974 | * @req: request | |
975 | * | |
2bfc6e56 WAA |
976 | * This may split a request into subrequests which are all part of the |
977 | * same page group. | |
978 | * | |
bcb71bba TM |
979 | * Returns true if the request 'req' was successfully coalesced into the |
980 | * existing list of pages 'desc'. | |
981 | */ | |
d9156f9f | 982 | static int __nfs_pageio_add_request(struct nfs_pageio_descriptor *desc, |
8b09bee3 | 983 | struct nfs_page *req) |
bcb71bba | 984 | { |
48d635f1 | 985 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
a7d42ddb | 986 | |
2bfc6e56 WAA |
987 | struct nfs_page *subreq; |
988 | unsigned int bytes_left = 0; | |
989 | unsigned int offset, pgbase; | |
990 | ||
bfd484a5 | 991 | nfs_page_group_lock(req, false); |
2bfc6e56 WAA |
992 | |
993 | subreq = req; | |
994 | bytes_left = subreq->wb_bytes; | |
995 | offset = subreq->wb_offset; | |
996 | pgbase = subreq->wb_pgbase; | |
997 | ||
998 | do { | |
999 | if (!nfs_pageio_do_add_request(desc, subreq)) { | |
1000 | /* make sure pg_test call(s) did nothing */ | |
1001 | WARN_ON_ONCE(subreq->wb_bytes != bytes_left); | |
1002 | WARN_ON_ONCE(subreq->wb_offset != offset); | |
1003 | WARN_ON_ONCE(subreq->wb_pgbase != pgbase); | |
1004 | ||
1005 | nfs_page_group_unlock(req); | |
1006 | desc->pg_moreio = 1; | |
1007 | nfs_pageio_doio(desc); | |
1008 | if (desc->pg_error < 0) | |
1009 | return 0; | |
a7d42ddb | 1010 | if (mirror->pg_recoalesce) |
2bfc6e56 WAA |
1011 | return 0; |
1012 | /* retry add_request for this subreq */ | |
bfd484a5 | 1013 | nfs_page_group_lock(req, false); |
2bfc6e56 WAA |
1014 | continue; |
1015 | } | |
1016 | ||
1017 | /* check for buggy pg_test call(s) */ | |
1018 | WARN_ON_ONCE(subreq->wb_bytes + subreq->wb_pgbase > PAGE_SIZE); | |
1019 | WARN_ON_ONCE(subreq->wb_bytes > bytes_left); | |
1020 | WARN_ON_ONCE(subreq->wb_bytes == 0); | |
1021 | ||
1022 | bytes_left -= subreq->wb_bytes; | |
1023 | offset += subreq->wb_bytes; | |
1024 | pgbase += subreq->wb_bytes; | |
1025 | ||
1026 | if (bytes_left) { | |
1027 | subreq = nfs_create_request(req->wb_context, | |
1028 | req->wb_page, | |
1029 | subreq, pgbase, bytes_left); | |
c1109558 TM |
1030 | if (IS_ERR(subreq)) |
1031 | goto err_ptr; | |
2bfc6e56 WAA |
1032 | nfs_lock_request(subreq); |
1033 | subreq->wb_offset = offset; | |
1034 | subreq->wb_index = req->wb_index; | |
1035 | } | |
1036 | } while (bytes_left > 0); | |
1037 | ||
1038 | nfs_page_group_unlock(req); | |
bcb71bba | 1039 | return 1; |
c1109558 TM |
1040 | err_ptr: |
1041 | desc->pg_error = PTR_ERR(subreq); | |
1042 | nfs_page_group_unlock(req); | |
1043 | return 0; | |
bcb71bba TM |
1044 | } |
1045 | ||
d9156f9f TM |
1046 | static int nfs_do_recoalesce(struct nfs_pageio_descriptor *desc) |
1047 | { | |
48d635f1 | 1048 | struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc); |
d9156f9f TM |
1049 | LIST_HEAD(head); |
1050 | ||
1051 | do { | |
a7d42ddb WAA |
1052 | list_splice_init(&mirror->pg_list, &head); |
1053 | mirror->pg_bytes_written -= mirror->pg_count; | |
1054 | mirror->pg_count = 0; | |
1055 | mirror->pg_base = 0; | |
1056 | mirror->pg_recoalesce = 0; | |
1057 | ||
d9156f9f TM |
1058 | while (!list_empty(&head)) { |
1059 | struct nfs_page *req; | |
1060 | ||
1061 | req = list_first_entry(&head, struct nfs_page, wb_list); | |
1062 | nfs_list_remove_request(req); | |
1063 | if (__nfs_pageio_add_request(desc, req)) | |
1064 | continue; | |
03d5eb65 TM |
1065 | if (desc->pg_error < 0) { |
1066 | list_splice_tail(&head, &mirror->pg_list); | |
1067 | mirror->pg_recoalesce = 1; | |
d9156f9f | 1068 | return 0; |
03d5eb65 | 1069 | } |
d9156f9f TM |
1070 | break; |
1071 | } | |
a7d42ddb | 1072 | } while (mirror->pg_recoalesce); |
d9156f9f TM |
1073 | return 1; |
1074 | } | |
1075 | ||
a7d42ddb | 1076 | static int nfs_pageio_add_request_mirror(struct nfs_pageio_descriptor *desc, |
d9156f9f TM |
1077 | struct nfs_page *req) |
1078 | { | |
1079 | int ret; | |
1080 | ||
1081 | do { | |
1082 | ret = __nfs_pageio_add_request(desc, req); | |
1083 | if (ret) | |
1084 | break; | |
1085 | if (desc->pg_error < 0) | |
1086 | break; | |
1087 | ret = nfs_do_recoalesce(desc); | |
1088 | } while (ret); | |
a7d42ddb | 1089 | |
d9156f9f TM |
1090 | return ret; |
1091 | } | |
1092 | ||
a7d42ddb WAA |
1093 | int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc, |
1094 | struct nfs_page *req) | |
1095 | { | |
1096 | u32 midx; | |
1097 | unsigned int pgbase, offset, bytes; | |
1098 | struct nfs_page *dupreq, *lastreq; | |
1099 | ||
1100 | pgbase = req->wb_pgbase; | |
1101 | offset = req->wb_offset; | |
1102 | bytes = req->wb_bytes; | |
1103 | ||
1104 | nfs_pageio_setup_mirroring(desc, req); | |
d600ad1f | 1105 | if (desc->pg_error < 0) |
c18b96a1 | 1106 | goto out_failed; |
a7d42ddb WAA |
1107 | |
1108 | for (midx = 0; midx < desc->pg_mirror_count; midx++) { | |
1109 | if (midx) { | |
1110 | nfs_page_group_lock(req, false); | |
1111 | ||
1112 | /* find the last request */ | |
1113 | for (lastreq = req->wb_head; | |
1114 | lastreq->wb_this_page != req->wb_head; | |
1115 | lastreq = lastreq->wb_this_page) | |
1116 | ; | |
1117 | ||
1118 | dupreq = nfs_create_request(req->wb_context, | |
1119 | req->wb_page, lastreq, pgbase, bytes); | |
1120 | ||
1121 | if (IS_ERR(dupreq)) { | |
1122 | nfs_page_group_unlock(req); | |
c18b96a1 PT |
1123 | desc->pg_error = PTR_ERR(dupreq); |
1124 | goto out_failed; | |
a7d42ddb WAA |
1125 | } |
1126 | ||
1127 | nfs_lock_request(dupreq); | |
1128 | nfs_page_group_unlock(req); | |
1129 | dupreq->wb_offset = offset; | |
1130 | dupreq->wb_index = req->wb_index; | |
1131 | } else | |
1132 | dupreq = req; | |
1133 | ||
47af81f2 PT |
1134 | if (nfs_pgio_has_mirroring(desc)) |
1135 | desc->pg_mirror_idx = midx; | |
a7d42ddb | 1136 | if (!nfs_pageio_add_request_mirror(desc, dupreq)) |
c18b96a1 | 1137 | goto out_failed; |
a7d42ddb WAA |
1138 | } |
1139 | ||
1140 | return 1; | |
c18b96a1 PT |
1141 | |
1142 | out_failed: | |
1143 | /* | |
1144 | * We might have failed before sending any reqs over wire. | |
2bff2288 | 1145 | * Clean up rest of the reqs in mirror pg_list. |
c18b96a1 | 1146 | */ |
2bff2288 PT |
1147 | if (desc->pg_error) { |
1148 | struct nfs_pgio_mirror *mirror; | |
1149 | void (*func)(struct list_head *); | |
1150 | ||
1151 | /* remember fatal errors */ | |
1152 | if (nfs_error_is_fatal(desc->pg_error)) | |
1153 | mapping_set_error(desc->pg_inode->i_mapping, | |
1154 | desc->pg_error); | |
1155 | ||
1156 | func = desc->pg_completion_ops->error_cleanup; | |
1157 | for (midx = 0; midx < desc->pg_mirror_count; midx++) { | |
1158 | mirror = &desc->pg_mirrors[midx]; | |
1159 | func(&mirror->pg_list); | |
1160 | } | |
1161 | } | |
c18b96a1 | 1162 | return 0; |
a7d42ddb WAA |
1163 | } |
1164 | ||
1165 | /* | |
1166 | * nfs_pageio_complete_mirror - Complete I/O on the current mirror of an | |
1167 | * nfs_pageio_descriptor | |
1168 | * @desc: pointer to io descriptor | |
dfad7000 | 1169 | * @mirror_idx: pointer to mirror index |
a7d42ddb WAA |
1170 | */ |
1171 | static void nfs_pageio_complete_mirror(struct nfs_pageio_descriptor *desc, | |
1172 | u32 mirror_idx) | |
1173 | { | |
1174 | struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[mirror_idx]; | |
1175 | u32 restore_idx = desc->pg_mirror_idx; | |
1176 | ||
47af81f2 PT |
1177 | if (nfs_pgio_has_mirroring(desc)) |
1178 | desc->pg_mirror_idx = mirror_idx; | |
a7d42ddb WAA |
1179 | for (;;) { |
1180 | nfs_pageio_doio(desc); | |
1181 | if (!mirror->pg_recoalesce) | |
1182 | break; | |
1183 | if (!nfs_do_recoalesce(desc)) | |
1184 | break; | |
1185 | } | |
1186 | desc->pg_mirror_idx = restore_idx; | |
1187 | } | |
1188 | ||
53113ad3 WAA |
1189 | /* |
1190 | * nfs_pageio_resend - Transfer requests to new descriptor and resend | |
1191 | * @hdr - the pgio header to move request from | |
1192 | * @desc - the pageio descriptor to add requests to | |
1193 | * | |
1194 | * Try to move each request (nfs_page) from @hdr to @desc then attempt | |
1195 | * to send them. | |
1196 | * | |
1197 | * Returns 0 on success and < 0 on error. | |
1198 | */ | |
1199 | int nfs_pageio_resend(struct nfs_pageio_descriptor *desc, | |
1200 | struct nfs_pgio_header *hdr) | |
1201 | { | |
1202 | LIST_HEAD(failed); | |
1203 | ||
1204 | desc->pg_dreq = hdr->dreq; | |
1205 | while (!list_empty(&hdr->pages)) { | |
1206 | struct nfs_page *req = nfs_list_entry(hdr->pages.next); | |
1207 | ||
1208 | nfs_list_remove_request(req); | |
1209 | if (!nfs_pageio_add_request(desc, req)) | |
1210 | nfs_list_add_request(req, &failed); | |
1211 | } | |
1212 | nfs_pageio_complete(desc); | |
1213 | if (!list_empty(&failed)) { | |
1214 | list_move(&failed, &hdr->pages); | |
d600ad1f | 1215 | return desc->pg_error < 0 ? desc->pg_error : -EIO; |
53113ad3 WAA |
1216 | } |
1217 | return 0; | |
1218 | } | |
1219 | EXPORT_SYMBOL_GPL(nfs_pageio_resend); | |
d9156f9f | 1220 | |
bcb71bba | 1221 | /** |
2176bf42 | 1222 | * nfs_pageio_complete - Complete I/O then cleanup an nfs_pageio_descriptor |
bcb71bba TM |
1223 | * @desc: pointer to io descriptor |
1224 | */ | |
1225 | void nfs_pageio_complete(struct nfs_pageio_descriptor *desc) | |
1226 | { | |
a7d42ddb WAA |
1227 | u32 midx; |
1228 | ||
1229 | for (midx = 0; midx < desc->pg_mirror_count; midx++) | |
1230 | nfs_pageio_complete_mirror(desc, midx); | |
2176bf42 WAA |
1231 | |
1232 | if (desc->pg_ops->pg_cleanup) | |
1233 | desc->pg_ops->pg_cleanup(desc); | |
a7d42ddb | 1234 | nfs_pageio_cleanup_mirroring(desc); |
bcb71bba TM |
1235 | } |
1236 | ||
7fe7f848 TM |
1237 | /** |
1238 | * nfs_pageio_cond_complete - Conditional I/O completion | |
1239 | * @desc: pointer to io descriptor | |
1240 | * @index: page index | |
1241 | * | |
1242 | * It is important to ensure that processes don't try to take locks | |
1243 | * on non-contiguous ranges of pages as that might deadlock. This | |
1244 | * function should be called before attempting to wait on a locked | |
1245 | * nfs_page. It will complete the I/O if the page index 'index' | |
1246 | * is not contiguous with the existing list of pages in 'desc'. | |
1247 | */ | |
1248 | void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *desc, pgoff_t index) | |
1249 | { | |
a7d42ddb WAA |
1250 | struct nfs_pgio_mirror *mirror; |
1251 | struct nfs_page *prev; | |
1252 | u32 midx; | |
1253 | ||
1254 | for (midx = 0; midx < desc->pg_mirror_count; midx++) { | |
1255 | mirror = &desc->pg_mirrors[midx]; | |
1256 | if (!list_empty(&mirror->pg_list)) { | |
1257 | prev = nfs_list_entry(mirror->pg_list.prev); | |
1258 | if (index != prev->wb_index + 1) | |
1259 | nfs_pageio_complete_mirror(desc, midx); | |
1260 | } | |
7fe7f848 TM |
1261 | } |
1262 | } | |
1263 | ||
f7b422b1 | 1264 | int __init nfs_init_nfspagecache(void) |
1da177e4 LT |
1265 | { |
1266 | nfs_page_cachep = kmem_cache_create("nfs_page", | |
1267 | sizeof(struct nfs_page), | |
1268 | 0, SLAB_HWCACHE_ALIGN, | |
20c2df83 | 1269 | NULL); |
1da177e4 LT |
1270 | if (nfs_page_cachep == NULL) |
1271 | return -ENOMEM; | |
1272 | ||
1273 | return 0; | |
1274 | } | |
1275 | ||
266bee88 | 1276 | void nfs_destroy_nfspagecache(void) |
1da177e4 | 1277 | { |
1a1d92c1 | 1278 | kmem_cache_destroy(nfs_page_cachep); |
1da177e4 LT |
1279 | } |
1280 | ||
ef2c488c | 1281 | static const struct rpc_call_ops nfs_pgio_common_ops = { |
6f92fa45 AS |
1282 | .rpc_call_prepare = nfs_pgio_prepare, |
1283 | .rpc_call_done = nfs_pgio_result, | |
1284 | .rpc_release = nfs_pgio_release, | |
1285 | }; | |
41d8d5b7 AS |
1286 | |
1287 | const struct nfs_pageio_ops nfs_pgio_rw_ops = { | |
1288 | .pg_test = nfs_generic_pg_test, | |
1289 | .pg_doio = nfs_generic_pg_pgios, | |
1290 | }; |