Commit | Line | Data |
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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 | |
e18b890b | 27 | static struct kmem_cache *nfs_page_cachep; |
1da177e4 | 28 | |
30dd374f FI |
29 | bool nfs_pgarray_set(struct nfs_page_array *p, unsigned int pagecount) |
30 | { | |
31 | p->npages = pagecount; | |
32 | if (pagecount <= ARRAY_SIZE(p->page_array)) | |
33 | p->pagevec = p->page_array; | |
34 | else { | |
35 | p->pagevec = kcalloc(pagecount, sizeof(struct page *), GFP_KERNEL); | |
36 | if (!p->pagevec) | |
37 | p->npages = 0; | |
38 | } | |
39 | return p->pagevec != NULL; | |
40 | } | |
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 | { | |
46 | hdr->req = nfs_list_entry(desc->pg_list.next); | |
47 | hdr->inode = desc->pg_inode; | |
48 | hdr->cred = hdr->req->wb_context->cred; | |
49 | hdr->io_start = req_offset(hdr->req); | |
50 | hdr->good_bytes = desc->pg_count; | |
584aa810 | 51 | hdr->dreq = desc->pg_dreq; |
f6166384 | 52 | hdr->layout_private = desc->pg_layout_private; |
4db6e0b7 | 53 | hdr->release = release; |
061ae2ed | 54 | hdr->completion_ops = desc->pg_completion_ops; |
584aa810 FI |
55 | if (hdr->completion_ops->init_hdr) |
56 | hdr->completion_ops->init_hdr(hdr); | |
4db6e0b7 | 57 | } |
89d77c8f | 58 | EXPORT_SYMBOL_GPL(nfs_pgheader_init); |
4db6e0b7 FI |
59 | |
60 | void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos) | |
61 | { | |
62 | spin_lock(&hdr->lock); | |
63 | if (pos < hdr->io_start + hdr->good_bytes) { | |
64 | set_bit(NFS_IOHDR_ERROR, &hdr->flags); | |
65 | clear_bit(NFS_IOHDR_EOF, &hdr->flags); | |
66 | hdr->good_bytes = pos - hdr->io_start; | |
67 | hdr->error = error; | |
68 | } | |
69 | spin_unlock(&hdr->lock); | |
70 | } | |
71 | ||
1da177e4 LT |
72 | static inline struct nfs_page * |
73 | nfs_page_alloc(void) | |
74 | { | |
192e501b | 75 | struct nfs_page *p = kmem_cache_zalloc(nfs_page_cachep, GFP_NOIO); |
72895b1a | 76 | if (p) |
1da177e4 | 77 | INIT_LIST_HEAD(&p->wb_list); |
1da177e4 LT |
78 | return p; |
79 | } | |
80 | ||
81 | static inline void | |
82 | nfs_page_free(struct nfs_page *p) | |
83 | { | |
84 | kmem_cache_free(nfs_page_cachep, p); | |
85 | } | |
86 | ||
577b4232 TM |
87 | static void |
88 | nfs_iocounter_inc(struct nfs_io_counter *c) | |
89 | { | |
90 | atomic_inc(&c->io_count); | |
91 | } | |
92 | ||
93 | static void | |
94 | nfs_iocounter_dec(struct nfs_io_counter *c) | |
95 | { | |
96 | if (atomic_dec_and_test(&c->io_count)) { | |
97 | clear_bit(NFS_IO_INPROGRESS, &c->flags); | |
98 | smp_mb__after_clear_bit(); | |
99 | wake_up_bit(&c->flags, NFS_IO_INPROGRESS); | |
100 | } | |
101 | } | |
102 | ||
103 | static int | |
104 | __nfs_iocounter_wait(struct nfs_io_counter *c) | |
105 | { | |
106 | wait_queue_head_t *wq = bit_waitqueue(&c->flags, NFS_IO_INPROGRESS); | |
107 | DEFINE_WAIT_BIT(q, &c->flags, NFS_IO_INPROGRESS); | |
108 | int ret = 0; | |
109 | ||
110 | do { | |
111 | prepare_to_wait(wq, &q.wait, TASK_KILLABLE); | |
112 | set_bit(NFS_IO_INPROGRESS, &c->flags); | |
113 | if (atomic_read(&c->io_count) == 0) | |
114 | break; | |
115 | ret = nfs_wait_bit_killable(&c->flags); | |
116 | } while (atomic_read(&c->io_count) != 0); | |
117 | finish_wait(wq, &q.wait); | |
118 | return ret; | |
119 | } | |
120 | ||
121 | /** | |
122 | * nfs_iocounter_wait - wait for i/o to complete | |
123 | * @c: nfs_io_counter to use | |
124 | * | |
125 | * returns -ERESTARTSYS if interrupted by a fatal signal. | |
126 | * Otherwise returns 0 once the io_count hits 0. | |
127 | */ | |
128 | int | |
129 | nfs_iocounter_wait(struct nfs_io_counter *c) | |
130 | { | |
131 | if (atomic_read(&c->io_count) == 0) | |
132 | return 0; | |
133 | return __nfs_iocounter_wait(c); | |
134 | } | |
135 | ||
1da177e4 LT |
136 | /** |
137 | * nfs_create_request - Create an NFS read/write request. | |
c02f557d | 138 | * @ctx: open context to use |
1da177e4 LT |
139 | * @inode: inode to which the request is attached |
140 | * @page: page to write | |
141 | * @offset: starting offset within the page for the write | |
142 | * @count: number of bytes to read/write | |
143 | * | |
144 | * The page must be locked by the caller. This makes sure we never | |
a19b89ca | 145 | * create two different requests for the same page. |
1da177e4 LT |
146 | * User should ensure it is safe to sleep in this function. |
147 | */ | |
148 | struct nfs_page * | |
149 | nfs_create_request(struct nfs_open_context *ctx, struct inode *inode, | |
150 | struct page *page, | |
151 | unsigned int offset, unsigned int count) | |
152 | { | |
1da177e4 | 153 | struct nfs_page *req; |
b3c54de6 | 154 | struct nfs_lock_context *l_ctx; |
1da177e4 | 155 | |
c58c8441 TM |
156 | if (test_bit(NFS_CONTEXT_BAD, &ctx->flags)) |
157 | return ERR_PTR(-EBADF); | |
18eb8842 TM |
158 | /* try to allocate the request struct */ |
159 | req = nfs_page_alloc(); | |
160 | if (req == NULL) | |
161 | return ERR_PTR(-ENOMEM); | |
1da177e4 | 162 | |
015f0212 | 163 | /* get lock context early so we can deal with alloc failures */ |
b3c54de6 TM |
164 | l_ctx = nfs_get_lock_context(ctx); |
165 | if (IS_ERR(l_ctx)) { | |
015f0212 | 166 | nfs_page_free(req); |
b3c54de6 | 167 | return ERR_CAST(l_ctx); |
015f0212 | 168 | } |
b3c54de6 | 169 | req->wb_lock_context = l_ctx; |
577b4232 | 170 | nfs_iocounter_inc(&l_ctx->io_count); |
015f0212 | 171 | |
1da177e4 LT |
172 | /* Initialize the request struct. Initially, we assume a |
173 | * long write-back delay. This will be adjusted in | |
174 | * update_nfs_request below if the region is not locked. */ | |
175 | req->wb_page = page; | |
d56b4ddf | 176 | req->wb_index = page_file_index(page); |
1da177e4 LT |
177 | page_cache_get(page); |
178 | req->wb_offset = offset; | |
179 | req->wb_pgbase = offset; | |
180 | req->wb_bytes = count; | |
1da177e4 | 181 | req->wb_context = get_nfs_open_context(ctx); |
c03b4024 | 182 | kref_init(&req->wb_kref); |
1da177e4 LT |
183 | return req; |
184 | } | |
185 | ||
186 | /** | |
1d1afcbc | 187 | * nfs_unlock_request - Unlock request and wake up sleepers. |
1da177e4 LT |
188 | * @req: |
189 | */ | |
1d1afcbc | 190 | void nfs_unlock_request(struct nfs_page *req) |
1da177e4 LT |
191 | { |
192 | if (!NFS_WBACK_BUSY(req)) { | |
193 | printk(KERN_ERR "NFS: Invalid unlock attempted\n"); | |
194 | BUG(); | |
195 | } | |
196 | smp_mb__before_clear_bit(); | |
197 | clear_bit(PG_BUSY, &req->wb_flags); | |
198 | smp_mb__after_clear_bit(); | |
464a98bd | 199 | wake_up_bit(&req->wb_flags, PG_BUSY); |
3aff4ebb TM |
200 | } |
201 | ||
202 | /** | |
1d1afcbc TM |
203 | * nfs_unlock_and_release_request - Unlock request and release the nfs_page |
204 | * @req: | |
3aff4ebb | 205 | */ |
1d1afcbc | 206 | void nfs_unlock_and_release_request(struct nfs_page *req) |
3aff4ebb | 207 | { |
1d1afcbc | 208 | nfs_unlock_request(req); |
1da177e4 LT |
209 | nfs_release_request(req); |
210 | } | |
211 | ||
4d65c520 | 212 | /* |
1da177e4 LT |
213 | * nfs_clear_request - Free up all resources allocated to the request |
214 | * @req: | |
215 | * | |
bb6fbc45 TM |
216 | * Release page and open context resources associated with a read/write |
217 | * request after it has completed. | |
1da177e4 | 218 | */ |
4d65c520 | 219 | static void nfs_clear_request(struct nfs_page *req) |
1da177e4 | 220 | { |
cd52ed35 | 221 | struct page *page = req->wb_page; |
bb6fbc45 | 222 | struct nfs_open_context *ctx = req->wb_context; |
f11ac8db | 223 | struct nfs_lock_context *l_ctx = req->wb_lock_context; |
bb6fbc45 | 224 | |
cd52ed35 | 225 | if (page != NULL) { |
cd52ed35 | 226 | page_cache_release(page); |
1da177e4 LT |
227 | req->wb_page = NULL; |
228 | } | |
f11ac8db | 229 | if (l_ctx != NULL) { |
577b4232 | 230 | nfs_iocounter_dec(&l_ctx->io_count); |
f11ac8db TM |
231 | nfs_put_lock_context(l_ctx); |
232 | req->wb_lock_context = NULL; | |
233 | } | |
bb6fbc45 TM |
234 | if (ctx != NULL) { |
235 | put_nfs_open_context(ctx); | |
236 | req->wb_context = NULL; | |
237 | } | |
1da177e4 LT |
238 | } |
239 | ||
240 | ||
241 | /** | |
242 | * nfs_release_request - Release the count on an NFS read/write request | |
243 | * @req: request to release | |
244 | * | |
245 | * Note: Should never be called with the spinlock held! | |
246 | */ | |
c03b4024 | 247 | static void nfs_free_request(struct kref *kref) |
1da177e4 | 248 | { |
c03b4024 | 249 | struct nfs_page *req = container_of(kref, struct nfs_page, wb_kref); |
1da177e4 | 250 | |
bb6fbc45 | 251 | /* Release struct file and open context */ |
1da177e4 | 252 | nfs_clear_request(req); |
1da177e4 LT |
253 | nfs_page_free(req); |
254 | } | |
255 | ||
c03b4024 TM |
256 | void nfs_release_request(struct nfs_page *req) |
257 | { | |
258 | kref_put(&req->wb_kref, nfs_free_request); | |
259 | } | |
260 | ||
9f557cd8 TM |
261 | static int nfs_wait_bit_uninterruptible(void *word) |
262 | { | |
263 | io_schedule(); | |
264 | return 0; | |
265 | } | |
266 | ||
1da177e4 LT |
267 | /** |
268 | * nfs_wait_on_request - Wait for a request to complete. | |
269 | * @req: request to wait upon. | |
270 | * | |
150030b7 | 271 | * Interruptible by fatal signals only. |
1da177e4 LT |
272 | * The user is responsible for holding a count on the request. |
273 | */ | |
274 | int | |
275 | nfs_wait_on_request(struct nfs_page *req) | |
276 | { | |
9f557cd8 TM |
277 | return wait_on_bit(&req->wb_flags, PG_BUSY, |
278 | nfs_wait_bit_uninterruptible, | |
279 | TASK_UNINTERRUPTIBLE); | |
1da177e4 LT |
280 | } |
281 | ||
19345cb2 | 282 | bool nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, struct nfs_page *prev, struct nfs_page *req) |
5b36c7dc BH |
283 | { |
284 | /* | |
285 | * FIXME: ideally we should be able to coalesce all requests | |
286 | * that are not block boundary aligned, but currently this | |
287 | * is problematic for the case of bsize < PAGE_CACHE_SIZE, | |
288 | * since nfs_flush_multi and nfs_pagein_multi assume you | |
289 | * can have only one struct nfs_page. | |
290 | */ | |
291 | if (desc->pg_bsize < PAGE_SIZE) | |
292 | return 0; | |
293 | ||
294 | return desc->pg_count + req->wb_bytes <= desc->pg_bsize; | |
295 | } | |
19345cb2 | 296 | EXPORT_SYMBOL_GPL(nfs_generic_pg_test); |
5b36c7dc | 297 | |
1da177e4 | 298 | /** |
d8a5ad75 TM |
299 | * nfs_pageio_init - initialise a page io descriptor |
300 | * @desc: pointer to descriptor | |
bcb71bba TM |
301 | * @inode: pointer to inode |
302 | * @doio: pointer to io function | |
303 | * @bsize: io block size | |
304 | * @io_flags: extra parameters for the io function | |
d8a5ad75 | 305 | */ |
bcb71bba TM |
306 | void nfs_pageio_init(struct nfs_pageio_descriptor *desc, |
307 | struct inode *inode, | |
1751c363 | 308 | const struct nfs_pageio_ops *pg_ops, |
061ae2ed | 309 | const struct nfs_pgio_completion_ops *compl_ops, |
84dde76c | 310 | size_t bsize, |
bcb71bba | 311 | int io_flags) |
d8a5ad75 TM |
312 | { |
313 | INIT_LIST_HEAD(&desc->pg_list); | |
bcb71bba | 314 | desc->pg_bytes_written = 0; |
d8a5ad75 TM |
315 | desc->pg_count = 0; |
316 | desc->pg_bsize = bsize; | |
317 | desc->pg_base = 0; | |
b31268ac | 318 | desc->pg_moreio = 0; |
d9156f9f | 319 | desc->pg_recoalesce = 0; |
bcb71bba | 320 | desc->pg_inode = inode; |
1751c363 | 321 | desc->pg_ops = pg_ops; |
061ae2ed | 322 | desc->pg_completion_ops = compl_ops; |
bcb71bba TM |
323 | desc->pg_ioflags = io_flags; |
324 | desc->pg_error = 0; | |
94ad1c80 | 325 | desc->pg_lseg = NULL; |
584aa810 | 326 | desc->pg_dreq = NULL; |
f6166384 | 327 | desc->pg_layout_private = NULL; |
d8a5ad75 | 328 | } |
89d77c8f | 329 | EXPORT_SYMBOL_GPL(nfs_pageio_init); |
d8a5ad75 TM |
330 | |
331 | /** | |
332 | * nfs_can_coalesce_requests - test two requests for compatibility | |
333 | * @prev: pointer to nfs_page | |
334 | * @req: pointer to nfs_page | |
335 | * | |
336 | * The nfs_page structures 'prev' and 'req' are compared to ensure that the | |
337 | * page data area they describe is contiguous, and that their RPC | |
338 | * credentials, NFSv4 open state, and lockowners are the same. | |
339 | * | |
340 | * Return 'true' if this is the case, else return 'false'. | |
341 | */ | |
18ad0a9f BH |
342 | static bool nfs_can_coalesce_requests(struct nfs_page *prev, |
343 | struct nfs_page *req, | |
344 | struct nfs_pageio_descriptor *pgio) | |
d8a5ad75 TM |
345 | { |
346 | if (req->wb_context->cred != prev->wb_context->cred) | |
18ad0a9f | 347 | return false; |
2a369153 TM |
348 | if (req->wb_lock_context->lockowner.l_owner != prev->wb_lock_context->lockowner.l_owner) |
349 | return false; | |
350 | if (req->wb_lock_context->lockowner.l_pid != prev->wb_lock_context->lockowner.l_pid) | |
18ad0a9f | 351 | return false; |
d8a5ad75 | 352 | if (req->wb_context->state != prev->wb_context->state) |
18ad0a9f | 353 | return false; |
d8a5ad75 | 354 | if (req->wb_pgbase != 0) |
18ad0a9f | 355 | return false; |
d8a5ad75 | 356 | if (prev->wb_pgbase + prev->wb_bytes != PAGE_CACHE_SIZE) |
18ad0a9f | 357 | return false; |
1825a0d0 FI |
358 | if (req_offset(req) != req_offset(prev) + prev->wb_bytes) |
359 | return false; | |
1751c363 | 360 | return pgio->pg_ops->pg_test(pgio, prev, req); |
d8a5ad75 TM |
361 | } |
362 | ||
363 | /** | |
bcb71bba | 364 | * nfs_pageio_do_add_request - Attempt to coalesce a request into a page list. |
d8a5ad75 TM |
365 | * @desc: destination io descriptor |
366 | * @req: request | |
367 | * | |
368 | * Returns true if the request 'req' was successfully coalesced into the | |
369 | * existing list of pages 'desc'. | |
370 | */ | |
bcb71bba TM |
371 | static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc, |
372 | struct nfs_page *req) | |
d8a5ad75 | 373 | { |
d8a5ad75 TM |
374 | if (desc->pg_count != 0) { |
375 | struct nfs_page *prev; | |
376 | ||
d8a5ad75 | 377 | prev = nfs_list_entry(desc->pg_list.prev); |
94ad1c80 | 378 | if (!nfs_can_coalesce_requests(prev, req, desc)) |
d8a5ad75 | 379 | return 0; |
5b36c7dc | 380 | } else { |
d8007d4d TM |
381 | if (desc->pg_ops->pg_init) |
382 | desc->pg_ops->pg_init(desc, req); | |
d8a5ad75 | 383 | desc->pg_base = req->wb_pgbase; |
5b36c7dc | 384 | } |
d8a5ad75 TM |
385 | nfs_list_remove_request(req); |
386 | nfs_list_add_request(req, &desc->pg_list); | |
5b36c7dc | 387 | desc->pg_count += req->wb_bytes; |
d8a5ad75 TM |
388 | return 1; |
389 | } | |
390 | ||
bcb71bba TM |
391 | /* |
392 | * Helper for nfs_pageio_add_request and nfs_pageio_complete | |
393 | */ | |
394 | static void nfs_pageio_doio(struct nfs_pageio_descriptor *desc) | |
395 | { | |
396 | if (!list_empty(&desc->pg_list)) { | |
1751c363 | 397 | int error = desc->pg_ops->pg_doio(desc); |
bcb71bba TM |
398 | if (error < 0) |
399 | desc->pg_error = error; | |
400 | else | |
401 | desc->pg_bytes_written += desc->pg_count; | |
402 | } | |
403 | if (list_empty(&desc->pg_list)) { | |
404 | desc->pg_count = 0; | |
405 | desc->pg_base = 0; | |
406 | } | |
407 | } | |
408 | ||
409 | /** | |
410 | * nfs_pageio_add_request - Attempt to coalesce a request into a page list. | |
411 | * @desc: destination io descriptor | |
412 | * @req: request | |
413 | * | |
414 | * Returns true if the request 'req' was successfully coalesced into the | |
415 | * existing list of pages 'desc'. | |
416 | */ | |
d9156f9f | 417 | static int __nfs_pageio_add_request(struct nfs_pageio_descriptor *desc, |
8b09bee3 | 418 | struct nfs_page *req) |
bcb71bba TM |
419 | { |
420 | while (!nfs_pageio_do_add_request(desc, req)) { | |
b31268ac | 421 | desc->pg_moreio = 1; |
bcb71bba TM |
422 | nfs_pageio_doio(desc); |
423 | if (desc->pg_error < 0) | |
424 | return 0; | |
b31268ac | 425 | desc->pg_moreio = 0; |
d9156f9f TM |
426 | if (desc->pg_recoalesce) |
427 | return 0; | |
bcb71bba TM |
428 | } |
429 | return 1; | |
430 | } | |
431 | ||
d9156f9f TM |
432 | static int nfs_do_recoalesce(struct nfs_pageio_descriptor *desc) |
433 | { | |
434 | LIST_HEAD(head); | |
435 | ||
436 | do { | |
437 | list_splice_init(&desc->pg_list, &head); | |
438 | desc->pg_bytes_written -= desc->pg_count; | |
439 | desc->pg_count = 0; | |
440 | desc->pg_base = 0; | |
441 | desc->pg_recoalesce = 0; | |
442 | ||
443 | while (!list_empty(&head)) { | |
444 | struct nfs_page *req; | |
445 | ||
446 | req = list_first_entry(&head, struct nfs_page, wb_list); | |
447 | nfs_list_remove_request(req); | |
448 | if (__nfs_pageio_add_request(desc, req)) | |
449 | continue; | |
450 | if (desc->pg_error < 0) | |
451 | return 0; | |
452 | break; | |
453 | } | |
454 | } while (desc->pg_recoalesce); | |
455 | return 1; | |
456 | } | |
457 | ||
458 | int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc, | |
459 | struct nfs_page *req) | |
460 | { | |
461 | int ret; | |
462 | ||
463 | do { | |
464 | ret = __nfs_pageio_add_request(desc, req); | |
465 | if (ret) | |
466 | break; | |
467 | if (desc->pg_error < 0) | |
468 | break; | |
469 | ret = nfs_do_recoalesce(desc); | |
470 | } while (ret); | |
471 | return ret; | |
472 | } | |
89d77c8f | 473 | EXPORT_SYMBOL_GPL(nfs_pageio_add_request); |
d9156f9f | 474 | |
bcb71bba TM |
475 | /** |
476 | * nfs_pageio_complete - Complete I/O on an nfs_pageio_descriptor | |
477 | * @desc: pointer to io descriptor | |
478 | */ | |
479 | void nfs_pageio_complete(struct nfs_pageio_descriptor *desc) | |
480 | { | |
d9156f9f TM |
481 | for (;;) { |
482 | nfs_pageio_doio(desc); | |
483 | if (!desc->pg_recoalesce) | |
484 | break; | |
485 | if (!nfs_do_recoalesce(desc)) | |
486 | break; | |
487 | } | |
bcb71bba | 488 | } |
89d77c8f | 489 | EXPORT_SYMBOL_GPL(nfs_pageio_complete); |
bcb71bba | 490 | |
7fe7f848 TM |
491 | /** |
492 | * nfs_pageio_cond_complete - Conditional I/O completion | |
493 | * @desc: pointer to io descriptor | |
494 | * @index: page index | |
495 | * | |
496 | * It is important to ensure that processes don't try to take locks | |
497 | * on non-contiguous ranges of pages as that might deadlock. This | |
498 | * function should be called before attempting to wait on a locked | |
499 | * nfs_page. It will complete the I/O if the page index 'index' | |
500 | * is not contiguous with the existing list of pages in 'desc'. | |
501 | */ | |
502 | void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *desc, pgoff_t index) | |
503 | { | |
504 | if (!list_empty(&desc->pg_list)) { | |
505 | struct nfs_page *prev = nfs_list_entry(desc->pg_list.prev); | |
506 | if (index != prev->wb_index + 1) | |
d9156f9f | 507 | nfs_pageio_complete(desc); |
7fe7f848 TM |
508 | } |
509 | } | |
510 | ||
f7b422b1 | 511 | int __init nfs_init_nfspagecache(void) |
1da177e4 LT |
512 | { |
513 | nfs_page_cachep = kmem_cache_create("nfs_page", | |
514 | sizeof(struct nfs_page), | |
515 | 0, SLAB_HWCACHE_ALIGN, | |
20c2df83 | 516 | NULL); |
1da177e4 LT |
517 | if (nfs_page_cachep == NULL) |
518 | return -ENOMEM; | |
519 | ||
520 | return 0; | |
521 | } | |
522 | ||
266bee88 | 523 | void nfs_destroy_nfspagecache(void) |
1da177e4 | 524 | { |
1a1d92c1 | 525 | kmem_cache_destroy(nfs_page_cachep); |
1da177e4 LT |
526 | } |
527 |