blob: 965db474f4b0d11d7a59fe839703c7505d714ce9 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/slab.h>
13#include <linux/file.h>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040014#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/sunrpc/clnt.h>
Trond Myklebust1313e602012-01-17 22:04:24 -050016#include <linux/nfs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#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>
Paul Gortmakerafeacc82011-05-26 16:00:52 -040022#include <linux/export.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
Trond Myklebust8d5658c2007-04-10 09:26:35 -040024#include "internal.h"
Fred Isamanbae724e2011-03-01 01:34:15 +000025#include "pnfs.h"
Trond Myklebust8d5658c2007-04-10 09:26:35 -040026
Anna Schumaker0eecb212014-05-06 09:12:32 -040027#define NFSDBG_FACILITY NFSDBG_PAGECACHE
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
Linus Torvalds1da177e2005-04-16 15:20:36 -070029static struct kmem_cache *nfs_page_cachep;
Anna Schumakeref2c4882014-05-06 09:12:36 -040030static const struct rpc_call_ops nfs_pgio_common_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
Anna Schumaker00bfa302014-05-06 09:12:29 -040032static bool nfs_pgarray_set(struct nfs_page_array *p, unsigned int pagecount)
Fred Isaman30dd3742012-04-20 14:47:45 -040033{
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
Peng Tao48d635f2014-11-10 08:35:35 +080045struct nfs_pgio_mirror *
46nfs_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}
52EXPORT_SYMBOL_GPL(nfs_pgio_current_mirror);
53
Fred Isaman4db6e0b2012-04-20 14:47:46 -040054void nfs_pgheader_init(struct nfs_pageio_descriptor *desc,
55 struct nfs_pgio_header *hdr,
56 void (*release)(struct nfs_pgio_header *hdr))
57{
Peng Tao48d635f2014-11-10 08:35:35 +080058 struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -040059
60
61 hdr->req = nfs_list_entry(mirror->pg_list.next);
Fred Isaman4db6e0b2012-04-20 14:47:46 -040062 hdr->inode = desc->pg_inode;
63 hdr->cred = hdr->req->wb_context->cred;
64 hdr->io_start = req_offset(hdr->req);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -040065 hdr->good_bytes = mirror->pg_count;
Fred Isaman584aa812012-04-20 14:47:51 -040066 hdr->dreq = desc->pg_dreq;
Peng Taof6166382012-08-02 15:36:09 +030067 hdr->layout_private = desc->pg_layout_private;
Fred Isaman4db6e0b2012-04-20 14:47:46 -040068 hdr->release = release;
Fred Isaman061ae2e2012-04-20 14:47:48 -040069 hdr->completion_ops = desc->pg_completion_ops;
Fred Isaman584aa812012-04-20 14:47:51 -040070 if (hdr->completion_ops->init_hdr)
71 hdr->completion_ops->init_hdr(hdr);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -040072
73 hdr->pgio_mirror_idx = desc->pg_mirror_idx;
Fred Isaman4db6e0b2012-04-20 14:47:46 -040074}
Bryan Schumaker89d77c82012-07-30 16:05:25 -040075EXPORT_SYMBOL_GPL(nfs_pgheader_init);
Fred Isaman4db6e0b2012-04-20 14:47:46 -040076
77void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos)
78{
79 spin_lock(&hdr->lock);
Trond Myklebuste9ae58a2015-08-17 12:57:07 -050080 if (!test_and_set_bit(NFS_IOHDR_ERROR, &hdr->flags)
81 || pos < hdr->io_start + hdr->good_bytes) {
Fred Isaman4db6e0b2012-04-20 14:47:46 -040082 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
Linus Torvalds1da177e2005-04-16 15:20:36 -070089static inline struct nfs_page *
90nfs_page_alloc(void)
91{
Mel Gorman192e5012012-07-31 16:45:16 -070092 struct nfs_page *p = kmem_cache_zalloc(nfs_page_cachep, GFP_NOIO);
Jesper Juhl72895b12010-12-09 23:17:15 +010093 if (p)
Linus Torvalds1da177e2005-04-16 15:20:36 -070094 INIT_LIST_HEAD(&p->wb_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -070095 return p;
96}
97
98static inline void
99nfs_page_free(struct nfs_page *p)
100{
101 kmem_cache_free(nfs_page_cachep, p);
102}
103
Trond Myklebust577b4232013-04-08 21:38:12 -0400104/**
105 * nfs_iocounter_wait - wait for i/o to complete
Benjamin Coddington210c7c12016-01-06 10:40:18 -0500106 * @l_ctx: nfs_lock_context with io_counter to use
Trond Myklebust577b4232013-04-08 21:38:12 -0400107 *
108 * returns -ERESTARTSYS if interrupted by a fatal signal.
109 * Otherwise returns 0 once the io_count hits 0.
110 */
111int
Benjamin Coddington210c7c12016-01-06 10:40:18 -0500112nfs_iocounter_wait(struct nfs_lock_context *l_ctx)
Trond Myklebust577b4232013-04-08 21:38:12 -0400113{
Benjamin Coddington210c7c12016-01-06 10:40:18 -0500114 return wait_on_atomic_t(&l_ctx->io_count, nfs_wait_atomic_killable,
115 TASK_KILLABLE);
Trond Myklebust577b4232013-04-08 21:38:12 -0400116}
117
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400118/*
119 * nfs_page_group_lock - lock the head of the page group
120 * @req - request in group that is to be locked
Weston Andros Adamsonfd2f3a02014-08-08 11:00:53 -0400121 * @nonblock - if true don't block waiting for lock
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400122 *
123 * this lock must be held if modifying the page group list
Weston Andros Adamsone7029202014-07-17 20:42:15 -0400124 *
Weston Andros Adamsonbc8a3092014-08-08 11:00:54 -0400125 * 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.
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400131 */
Weston Andros Adamsone7029202014-07-17 20:42:15 -0400132int
Weston Andros Adamsonfd2f3a02014-08-08 11:00:53 -0400133nfs_page_group_lock(struct nfs_page *req, bool nonblock)
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400134{
135 struct nfs_page *head = req->wb_head;
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400136
137 WARN_ON_ONCE(head != head->wb_head);
138
Weston Andros Adamsonbc8a3092014-08-08 11:00:54 -0400139 if (!test_and_set_bit(PG_HEADLOCK, &head->wb_flags))
140 return 0;
Weston Andros Adamsone7029202014-07-17 20:42:15 -0400141
Weston Andros Adamsonbc8a3092014-08-08 11:00:54 -0400142 if (!nonblock)
143 return wait_on_bit_lock(&head->wb_flags, PG_HEADLOCK,
144 TASK_UNINTERRUPTIBLE);
145
146 return -EAGAIN;
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400147}
148
149/*
Weston Andros Adamson7c3af972014-08-08 11:00:57 -0400150 * 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 */
155void
156nfs_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
166/*
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400167 * nfs_page_group_unlock - unlock the head of the page group
168 * @req - request in group that is to be unlocked
169 */
170void
171nfs_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
Linus Torvaldsd1e1cda2014-06-10 15:02:42 -0700177 smp_mb__before_atomic();
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400178 clear_bit(PG_HEADLOCK, &head->wb_flags);
Linus Torvaldsd1e1cda2014-06-10 15:02:42 -0700179 smp_mb__after_atomic();
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400180 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 */
188static bool
189nfs_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 */
220bool nfs_page_group_sync_on_bit(struct nfs_page *req, unsigned int bit)
221{
222 bool ret;
223
Weston Andros Adamsonfd2f3a02014-08-08 11:00:53 -0400224 nfs_page_group_lock(req, false);
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400225 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 */
237static inline void
238nfs_page_group_init(struct nfs_page *req, struct nfs_page *prev)
239{
Weston Andros Adamsoncb1410c2014-11-12 12:08:00 -0500240 struct inode *inode;
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400241 WARN_ON_ONCE(prev == req);
242
243 if (!prev) {
Weston Andros Adamson85710a82014-07-11 10:20:46 -0400244 /* a head request */
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400245 req->wb_head = req;
246 req->wb_this_page = req;
247 } else {
Weston Andros Adamson85710a82014-07-11 10:20:46 -0400248 /* a subrequest */
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400249 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
Weston Andros Adamson85710a82014-07-11 10:20:46 -0400255 /* 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
Weston Andros Adamsoncb1410c2014-11-12 12:08:00 -0500259 /* 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. */
Weston Andros Adamson17089a22014-07-11 10:20:45 -0400262 if (test_bit(PG_INODE_REF, &prev->wb_head->wb_flags)) {
Weston Andros Adamsoncb1410c2014-11-12 12:08:00 -0500263 inode = page_file_mapping(req->wb_page)->host;
Weston Andros Adamson17089a22014-07-11 10:20:45 -0400264 set_bit(PG_INODE_REF, &req->wb_flags);
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400265 kref_get(&req->wb_kref);
Weston Andros Adamsoncb1410c2014-11-12 12:08:00 -0500266 spin_lock(&inode->i_lock);
267 NFS_I(inode)->nrequests++;
268 spin_unlock(&inode->i_lock);
Weston Andros Adamson17089a22014-07-11 10:20:45 -0400269 }
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400270 }
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 */
280static void
281nfs_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
Weston Andros Adamson85710a82014-07-11 10:20:46 -0400286 /* subrequests must release the ref on the head request */
287 if (req->wb_head != req)
288 nfs_release_request(req->wb_head);
289
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400290 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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304/**
305 * nfs_create_request - Create an NFS read/write request.
Chuck Leverc02f5572011-10-25 12:17:43 -0400306 * @ctx: open context to use
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 * @page: page to write
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400308 * @last: last nfs request created for this page group or NULL if head
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 * @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
Jason Uhlenkotta19b89c2007-04-26 17:25:51 -0700313 * create two different requests for the same page.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 * User should ensure it is safe to sleep in this function.
315 */
316struct nfs_page *
Weston Andros Adamson8c8f1ac12014-05-15 11:56:42 -0400317nfs_create_request(struct nfs_open_context *ctx, struct page *page,
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400318 struct nfs_page *last, unsigned int offset,
319 unsigned int count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 struct nfs_page *req;
Trond Myklebustb3c54de2012-08-13 17:15:50 -0400322 struct nfs_lock_context *l_ctx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323
Trond Myklebustc58c8442013-03-18 19:45:14 -0400324 if (test_bit(NFS_CONTEXT_BAD, &ctx->flags))
325 return ERR_PTR(-EBADF);
Trond Myklebust18eb8842010-05-13 12:51:02 -0400326 /* try to allocate the request struct */
327 req = nfs_page_alloc();
328 if (req == NULL)
329 return ERR_PTR(-ENOMEM);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330
Jeff Layton015f0212010-10-28 10:10:37 -0400331 /* get lock context early so we can deal with alloc failures */
Trond Myklebustb3c54de2012-08-13 17:15:50 -0400332 l_ctx = nfs_get_lock_context(ctx);
333 if (IS_ERR(l_ctx)) {
Jeff Layton015f0212010-10-28 10:10:37 -0400334 nfs_page_free(req);
Trond Myklebustb3c54de2012-08-13 17:15:50 -0400335 return ERR_CAST(l_ctx);
Jeff Layton015f0212010-10-28 10:10:37 -0400336 }
Trond Myklebustb3c54de2012-08-13 17:15:50 -0400337 req->wb_lock_context = l_ctx;
Benjamin Coddington210c7c12016-01-06 10:40:18 -0500338 atomic_inc(&l_ctx->io_count);
Jeff Layton015f0212010-10-28 10:10:37 -0400339
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 /* 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;
Anna Schumaker67911c82016-01-19 14:37:30 -0500344 if (page) {
Huang Ying8cd79782016-10-07 17:00:24 -0700345 req->wb_index = page_index(page);
Anna Schumaker67911c82016-01-19 14:37:30 -0500346 get_page(page);
347 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 req->wb_offset = offset;
349 req->wb_pgbase = offset;
350 req->wb_bytes = count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 req->wb_context = get_nfs_open_context(ctx);
Trond Myklebustc03b4022007-06-17 13:26:38 -0400352 kref_init(&req->wb_kref);
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400353 nfs_page_group_init(req, last);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 return req;
355}
356
357/**
Trond Myklebust1d1afcb2012-05-09 14:04:55 -0400358 * nfs_unlock_request - Unlock request and wake up sleepers.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 * @req:
360 */
Trond Myklebust1d1afcb2012-05-09 14:04:55 -0400361void nfs_unlock_request(struct nfs_page *req)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362{
363 if (!NFS_WBACK_BUSY(req)) {
364 printk(KERN_ERR "NFS: Invalid unlock attempted\n");
365 BUG();
366 }
Peter Zijlstra4e857c52014-03-17 18:06:10 +0100367 smp_mb__before_atomic();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 clear_bit(PG_BUSY, &req->wb_flags);
Peter Zijlstra4e857c52014-03-17 18:06:10 +0100369 smp_mb__after_atomic();
Trond Myklebust464a98b2005-06-22 17:16:21 +0000370 wake_up_bit(&req->wb_flags, PG_BUSY);
Trond Myklebust3aff4eb2012-05-09 14:30:35 -0400371}
372
373/**
Trond Myklebust1d1afcb2012-05-09 14:04:55 -0400374 * nfs_unlock_and_release_request - Unlock request and release the nfs_page
375 * @req:
Trond Myklebust3aff4eb2012-05-09 14:30:35 -0400376 */
Trond Myklebust1d1afcb2012-05-09 14:04:55 -0400377void nfs_unlock_and_release_request(struct nfs_page *req)
Trond Myklebust3aff4eb2012-05-09 14:30:35 -0400378{
Trond Myklebust1d1afcb2012-05-09 14:04:55 -0400379 nfs_unlock_request(req);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 nfs_release_request(req);
381}
382
Trond Myklebust4d65c522011-03-25 14:15:11 -0400383/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 * nfs_clear_request - Free up all resources allocated to the request
385 * @req:
386 *
Trond Myklebustbb6fbc42010-03-11 09:19:35 -0500387 * Release page and open context resources associated with a read/write
388 * request after it has completed.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 */
Trond Myklebust4d65c522011-03-25 14:15:11 -0400390static void nfs_clear_request(struct nfs_page *req)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391{
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500392 struct page *page = req->wb_page;
Trond Myklebustbb6fbc42010-03-11 09:19:35 -0500393 struct nfs_open_context *ctx = req->wb_context;
Trond Myklebustf11ac8d2010-06-25 16:35:53 -0400394 struct nfs_lock_context *l_ctx = req->wb_lock_context;
Trond Myklebustbb6fbc42010-03-11 09:19:35 -0500395
Trond Myklebustcd52ed32006-03-20 13:44:04 -0500396 if (page != NULL) {
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300397 put_page(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 req->wb_page = NULL;
399 }
Trond Myklebustf11ac8d2010-06-25 16:35:53 -0400400 if (l_ctx != NULL) {
Benjamin Coddington210c7c12016-01-06 10:40:18 -0500401 if (atomic_dec_and_test(&l_ctx->io_count))
402 wake_up_atomic_t(&l_ctx->io_count);
Trond Myklebustf11ac8d2010-06-25 16:35:53 -0400403 nfs_put_lock_context(l_ctx);
404 req->wb_lock_context = NULL;
405 }
Trond Myklebustbb6fbc42010-03-11 09:19:35 -0500406 if (ctx != NULL) {
407 put_nfs_open_context(ctx);
408 req->wb_context = NULL;
409 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410}
411
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412/**
413 * nfs_release_request - Release the count on an NFS read/write request
414 * @req: request to release
415 *
416 * Note: Should never be called with the spinlock held!
417 */
Weston Andros Adamsond4581382014-07-11 10:20:48 -0400418void nfs_free_request(struct nfs_page *req)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419{
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400420 WARN_ON_ONCE(req->wb_this_page != req);
421
422 /* extra debug: make sure no sync bits are still set */
423 WARN_ON_ONCE(test_bit(PG_TEARDOWN, &req->wb_flags));
Weston Andros Adamson67d03382014-05-15 11:56:46 -0400424 WARN_ON_ONCE(test_bit(PG_UNLOCKPAGE, &req->wb_flags));
425 WARN_ON_ONCE(test_bit(PG_UPTODATE, &req->wb_flags));
Weston Andros Adamson20633f02014-05-15 11:56:47 -0400426 WARN_ON_ONCE(test_bit(PG_WB_END, &req->wb_flags));
427 WARN_ON_ONCE(test_bit(PG_REMOVE, &req->wb_flags));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428
Trond Myklebustbb6fbc42010-03-11 09:19:35 -0500429 /* Release struct file and open context */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430 nfs_clear_request(req);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 nfs_page_free(req);
432}
433
Trond Myklebustc03b4022007-06-17 13:26:38 -0400434void nfs_release_request(struct nfs_page *req)
435{
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400436 kref_put(&req->wb_kref, nfs_page_group_destroy);
Trond Myklebust9f557cd2010-02-03 08:27:22 -0500437}
438
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439/**
440 * nfs_wait_on_request - Wait for a request to complete.
441 * @req: request to wait upon.
442 *
Matthew Wilcox150030b2007-12-06 16:24:39 -0500443 * Interruptible by fatal signals only.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 * The user is responsible for holding a count on the request.
445 */
446int
447nfs_wait_on_request(struct nfs_page *req)
448{
NeilBrown74316202014-07-07 15:16:04 +1000449 return wait_on_bit_io(&req->wb_flags, PG_BUSY,
450 TASK_UNINTERRUPTIBLE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451}
452
Weston Andros Adamsonb4fdac12014-05-15 11:56:43 -0400453/*
454 * nfs_generic_pg_test - determine if requests can be coalesced
455 * @desc: pointer to descriptor
456 * @prev: previous request in desc, or NULL
457 * @req: this request
458 *
459 * Returns zero if @req can be coalesced into @desc, otherwise it returns
460 * the size of the request.
461 */
462size_t nfs_generic_pg_test(struct nfs_pageio_descriptor *desc,
463 struct nfs_page *prev, struct nfs_page *req)
Boaz Harrosh5b36c7d2011-05-29 11:45:39 +0300464{
Peng Tao48d635f2014-11-10 08:35:35 +0800465 struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400466
467
468 if (mirror->pg_count > mirror->pg_bsize) {
Weston Andros Adamsonf0cb9ab2014-05-15 11:56:52 -0400469 /* should never happen */
470 WARN_ON_ONCE(1);
Boaz Harrosh5b36c7d2011-05-29 11:45:39 +0300471 return 0;
Weston Andros Adamsonf0cb9ab2014-05-15 11:56:52 -0400472 }
Boaz Harrosh5b36c7d2011-05-29 11:45:39 +0300473
Christoph Hellwig2e11f822014-08-21 11:09:17 -0500474 /*
475 * Limit the request size so that we can still allocate a page array
476 * for it without upsetting the slab allocator.
477 */
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400478 if (((mirror->pg_count + req->wb_bytes) >> PAGE_SHIFT) *
Peng Tao048883e2015-09-11 11:14:06 +0800479 sizeof(struct page *) > PAGE_SIZE)
Christoph Hellwig2e11f822014-08-21 11:09:17 -0500480 return 0;
481
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400482 return min(mirror->pg_bsize - mirror->pg_count, (size_t)req->wb_bytes);
Boaz Harrosh5b36c7d2011-05-29 11:45:39 +0300483}
Benny Halevy19345cb2011-06-19 18:33:46 -0400484EXPORT_SYMBOL_GPL(nfs_generic_pg_test);
Boaz Harrosh5b36c7d2011-05-29 11:45:39 +0300485
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400486struct nfs_pgio_header *nfs_pgio_header_alloc(const struct nfs_rw_ops *ops)
Anna Schumaker00bfa302014-05-06 09:12:29 -0400487{
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400488 struct nfs_pgio_header *hdr = ops->rw_alloc_header();
Anna Schumaker00bfa302014-05-06 09:12:29 -0400489
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400490 if (hdr) {
Anna Schumaker4a0de552014-05-06 09:12:30 -0400491 INIT_LIST_HEAD(&hdr->pages);
Anna Schumaker4a0de552014-05-06 09:12:30 -0400492 spin_lock_init(&hdr->lock);
Anna Schumaker4a0de552014-05-06 09:12:30 -0400493 hdr->rw_ops = ops;
494 }
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400495 return hdr;
Anna Schumaker4a0de552014-05-06 09:12:30 -0400496}
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400497EXPORT_SYMBOL_GPL(nfs_pgio_header_alloc);
Anna Schumaker4a0de552014-05-06 09:12:30 -0400498
499/*
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400500 * nfs_pgio_header_free - Free a read or write header
Anna Schumaker4a0de552014-05-06 09:12:30 -0400501 * @hdr: The header to free
502 */
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400503void nfs_pgio_header_free(struct nfs_pgio_header *hdr)
Anna Schumaker4a0de552014-05-06 09:12:30 -0400504{
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400505 hdr->rw_ops->rw_free_header(hdr);
Anna Schumaker4a0de552014-05-06 09:12:30 -0400506}
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400507EXPORT_SYMBOL_GPL(nfs_pgio_header_free);
Anna Schumaker4a0de552014-05-06 09:12:30 -0400508
509/**
Weston Andros Adamson4714fb52014-06-09 11:48:37 -0400510 * nfs_pgio_data_destroy - make @hdr suitable for reuse
511 *
512 * Frees memory and releases refs from nfs_generic_pgio, so that it may
513 * be called again.
514 *
515 * @hdr: A header that has had nfs_generic_pgio called
Anna Schumaker00bfa302014-05-06 09:12:29 -0400516 */
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400517void nfs_pgio_data_destroy(struct nfs_pgio_header *hdr)
Anna Schumaker00bfa302014-05-06 09:12:29 -0400518{
Trond Myklebust3caa0c62014-10-13 10:26:43 -0400519 if (hdr->args.context)
520 put_nfs_open_context(hdr->args.context);
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400521 if (hdr->page_array.pagevec != hdr->page_array.page_array)
522 kfree(hdr->page_array.pagevec);
Anna Schumaker00bfa302014-05-06 09:12:29 -0400523}
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400524EXPORT_SYMBOL_GPL(nfs_pgio_data_destroy);
Anna Schumaker00bfa302014-05-06 09:12:29 -0400525
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526/**
Anna Schumakerce595152014-05-06 09:12:34 -0400527 * nfs_pgio_rpcsetup - Set up arguments for a pageio call
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400528 * @hdr: The pageio hdr
Anna Schumakerce595152014-05-06 09:12:34 -0400529 * @count: Number of bytes to read
530 * @offset: Initial offset
531 * @how: How to commit data (writes only)
532 * @cinfo: Commit information for the call (writes only)
533 */
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400534static void nfs_pgio_rpcsetup(struct nfs_pgio_header *hdr,
Anna Schumakerce595152014-05-06 09:12:34 -0400535 unsigned int count, unsigned int offset,
536 int how, struct nfs_commit_info *cinfo)
537{
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400538 struct nfs_page *req = hdr->req;
Anna Schumakerce595152014-05-06 09:12:34 -0400539
540 /* Set up the RPC argument and reply structs
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400541 * NB: take care not to mess about with hdr->commit et al. */
Anna Schumakerce595152014-05-06 09:12:34 -0400542
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400543 hdr->args.fh = NFS_FH(hdr->inode);
544 hdr->args.offset = req_offset(req) + offset;
Anna Schumakerce595152014-05-06 09:12:34 -0400545 /* pnfs_set_layoutcommit needs this */
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400546 hdr->mds_offset = hdr->args.offset;
547 hdr->args.pgbase = req->wb_pgbase + offset;
548 hdr->args.pages = hdr->page_array.pagevec;
549 hdr->args.count = count;
550 hdr->args.context = get_nfs_open_context(req->wb_context);
551 hdr->args.lock_context = req->wb_lock_context;
552 hdr->args.stable = NFS_UNSTABLE;
Anna Schumakerce595152014-05-06 09:12:34 -0400553 switch (how & (FLUSH_STABLE | FLUSH_COND_STABLE)) {
554 case 0:
555 break;
556 case FLUSH_COND_STABLE:
557 if (nfs_reqs_to_commit(cinfo))
558 break;
559 default:
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400560 hdr->args.stable = NFS_FILE_SYNC;
Anna Schumakerce595152014-05-06 09:12:34 -0400561 }
562
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400563 hdr->res.fattr = &hdr->fattr;
564 hdr->res.count = count;
565 hdr->res.eof = 0;
Weston Andros Adamsonc65e6252014-06-09 11:48:36 -0400566 hdr->res.verf = &hdr->verf;
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400567 nfs_fattr_init(&hdr->fattr);
Anna Schumakerce595152014-05-06 09:12:34 -0400568}
569
570/**
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400571 * nfs_pgio_prepare - Prepare pageio hdr to go over the wire
Anna Schumakera4cdda52014-05-06 09:12:31 -0400572 * @task: The current task
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400573 * @calldata: pageio header to prepare
Anna Schumakera4cdda52014-05-06 09:12:31 -0400574 */
Anna Schumaker6f92fa42014-05-06 09:12:33 -0400575static void nfs_pgio_prepare(struct rpc_task *task, void *calldata)
Anna Schumakera4cdda52014-05-06 09:12:31 -0400576{
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400577 struct nfs_pgio_header *hdr = calldata;
Anna Schumakera4cdda52014-05-06 09:12:31 -0400578 int err;
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400579 err = NFS_PROTO(hdr->inode)->pgio_rpc_prepare(task, hdr);
Anna Schumakera4cdda52014-05-06 09:12:31 -0400580 if (err)
581 rpc_exit(task, err);
582}
583
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400584int nfs_initiate_pgio(struct rpc_clnt *clnt, struct nfs_pgio_header *hdr,
Peng Tao46a5ab42014-06-13 23:02:25 +0800585 struct rpc_cred *cred, const struct nfs_rpc_ops *rpc_ops,
Anna Schumaker1ed26f32014-05-06 09:12:37 -0400586 const struct rpc_call_ops *call_ops, int how, int flags)
587{
588 struct rpc_task *task;
589 struct rpc_message msg = {
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400590 .rpc_argp = &hdr->args,
591 .rpc_resp = &hdr->res,
Peng Tao46a5ab42014-06-13 23:02:25 +0800592 .rpc_cred = cred,
Anna Schumaker1ed26f32014-05-06 09:12:37 -0400593 };
594 struct rpc_task_setup task_setup_data = {
595 .rpc_client = clnt,
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400596 .task = &hdr->task,
Anna Schumaker1ed26f32014-05-06 09:12:37 -0400597 .rpc_message = &msg,
598 .callback_ops = call_ops,
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400599 .callback_data = hdr,
Anna Schumaker1ed26f32014-05-06 09:12:37 -0400600 .workqueue = nfsiod_workqueue,
601 .flags = RPC_TASK_ASYNC | flags,
602 };
603 int ret = 0;
604
Tom Haynesabde71f2014-06-09 13:12:20 -0700605 hdr->rw_ops->rw_initiate(hdr, &msg, rpc_ops, &task_setup_data, how);
Anna Schumaker1ed26f32014-05-06 09:12:37 -0400606
Kinglong Meeb4839eb2015-07-01 12:00:13 +0800607 dprintk("NFS: initiated pgio call "
Anna Schumaker1ed26f32014-05-06 09:12:37 -0400608 "(req %s/%llu, %u bytes @ offset %llu)\n",
Anna Schumaker343ae532014-06-20 13:30:26 -0400609 hdr->inode->i_sb->s_id,
610 (unsigned long long)NFS_FILEID(hdr->inode),
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400611 hdr->args.count,
612 (unsigned long long)hdr->args.offset);
Anna Schumaker1ed26f32014-05-06 09:12:37 -0400613
614 task = rpc_run_task(&task_setup_data);
615 if (IS_ERR(task)) {
616 ret = PTR_ERR(task);
617 goto out;
618 }
619 if (how & FLUSH_SYNC) {
620 ret = rpc_wait_for_completion_task(task);
621 if (ret == 0)
622 ret = task->tk_status;
623 }
624 rpc_put_task(task);
625out:
626 return ret;
627}
628EXPORT_SYMBOL_GPL(nfs_initiate_pgio);
629
Anna Schumakera4cdda52014-05-06 09:12:31 -0400630/**
Anna Schumaker844c9e62014-05-06 09:12:35 -0400631 * nfs_pgio_error - Clean up from a pageio error
632 * @desc: IO descriptor
633 * @hdr: pageio header
634 */
Peng Tao2bff2282015-12-05 02:03:17 +0800635static void nfs_pgio_error(struct nfs_pgio_header *hdr)
Anna Schumaker844c9e62014-05-06 09:12:35 -0400636{
Anna Schumaker844c9e62014-05-06 09:12:35 -0400637 set_bit(NFS_IOHDR_REDO, &hdr->flags);
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400638 nfs_pgio_data_destroy(hdr);
Weston Andros Adamson4714fb52014-06-09 11:48:37 -0400639 hdr->completion_ops->completion(hdr);
Anna Schumaker844c9e62014-05-06 09:12:35 -0400640}
641
642/**
Anna Schumakera4cdda52014-05-06 09:12:31 -0400643 * nfs_pgio_release - Release pageio data
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400644 * @calldata: The pageio header to release
Anna Schumakera4cdda52014-05-06 09:12:31 -0400645 */
Anna Schumaker6f92fa42014-05-06 09:12:33 -0400646static void nfs_pgio_release(void *calldata)
Anna Schumakera4cdda52014-05-06 09:12:31 -0400647{
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400648 struct nfs_pgio_header *hdr = calldata;
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400649 nfs_pgio_data_destroy(hdr);
Weston Andros Adamson4714fb52014-06-09 11:48:37 -0400650 hdr->completion_ops->completion(hdr);
Anna Schumakera4cdda52014-05-06 09:12:31 -0400651}
652
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400653static void nfs_pageio_mirror_init(struct nfs_pgio_mirror *mirror,
654 unsigned int bsize)
655{
656 INIT_LIST_HEAD(&mirror->pg_list);
657 mirror->pg_bytes_written = 0;
658 mirror->pg_count = 0;
659 mirror->pg_bsize = bsize;
660 mirror->pg_base = 0;
661 mirror->pg_recoalesce = 0;
662}
663
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664/**
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400665 * nfs_pageio_init - initialise a page io descriptor
666 * @desc: pointer to descriptor
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400667 * @inode: pointer to inode
Yijing Wangdfad7002015-06-18 19:37:13 +0800668 * @pg_ops: pointer to pageio operations
669 * @compl_ops: pointer to pageio completion operations
670 * @rw_ops: pointer to nfs read/write operations
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400671 * @bsize: io block size
672 * @io_flags: extra parameters for the io function
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400673 */
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400674void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
675 struct inode *inode,
Trond Myklebust1751c362011-06-10 13:30:23 -0400676 const struct nfs_pageio_ops *pg_ops,
Fred Isaman061ae2e2012-04-20 14:47:48 -0400677 const struct nfs_pgio_completion_ops *compl_ops,
Anna Schumaker4a0de552014-05-06 09:12:30 -0400678 const struct nfs_rw_ops *rw_ops,
Trond Myklebust84dde762007-05-04 14:44:06 -0400679 size_t bsize,
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400680 int io_flags)
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400681{
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400682 struct nfs_pgio_mirror *new;
683 int i;
684
Trond Myklebustb31268a2011-03-21 17:02:00 -0400685 desc->pg_moreio = 0;
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400686 desc->pg_inode = inode;
Trond Myklebust1751c362011-06-10 13:30:23 -0400687 desc->pg_ops = pg_ops;
Fred Isaman061ae2e2012-04-20 14:47:48 -0400688 desc->pg_completion_ops = compl_ops;
Anna Schumaker4a0de552014-05-06 09:12:30 -0400689 desc->pg_rw_ops = rw_ops;
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400690 desc->pg_ioflags = io_flags;
691 desc->pg_error = 0;
Fred Isaman94ad1c82011-03-01 01:34:14 +0000692 desc->pg_lseg = NULL;
Fred Isaman584aa812012-04-20 14:47:51 -0400693 desc->pg_dreq = NULL;
Peng Taof6166382012-08-02 15:36:09 +0300694 desc->pg_layout_private = NULL;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400695 desc->pg_bsize = bsize;
696
697 desc->pg_mirror_count = 1;
698 desc->pg_mirror_idx = 0;
699
700 if (pg_ops->pg_get_mirror_count) {
701 /* until we have a request, we don't have an lseg and no
702 * idea how many mirrors there will be */
703 new = kcalloc(NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX,
704 sizeof(struct nfs_pgio_mirror), GFP_KERNEL);
705 desc->pg_mirrors_dynamic = new;
706 desc->pg_mirrors = new;
707
708 for (i = 0; i < NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX; i++)
709 nfs_pageio_mirror_init(&desc->pg_mirrors[i], bsize);
710 } else {
711 desc->pg_mirrors_dynamic = NULL;
712 desc->pg_mirrors = desc->pg_mirrors_static;
713 nfs_pageio_mirror_init(&desc->pg_mirrors[0], bsize);
714 }
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400715}
Bryan Schumaker89d77c82012-07-30 16:05:25 -0400716EXPORT_SYMBOL_GPL(nfs_pageio_init);
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400717
Anna Schumaker0eecb212014-05-06 09:12:32 -0400718/**
719 * nfs_pgio_result - Basic pageio error handling
720 * @task: The task that ran
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400721 * @calldata: Pageio header to check
Anna Schumaker0eecb212014-05-06 09:12:32 -0400722 */
Anna Schumaker6f92fa42014-05-06 09:12:33 -0400723static void nfs_pgio_result(struct rpc_task *task, void *calldata)
Anna Schumaker0eecb212014-05-06 09:12:32 -0400724{
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400725 struct nfs_pgio_header *hdr = calldata;
726 struct inode *inode = hdr->inode;
Anna Schumaker0eecb212014-05-06 09:12:32 -0400727
728 dprintk("NFS: %s: %5u, (status %d)\n", __func__,
729 task->tk_pid, task->tk_status);
730
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400731 if (hdr->rw_ops->rw_done(task, hdr, inode) != 0)
Anna Schumaker0eecb212014-05-06 09:12:32 -0400732 return;
733 if (task->tk_status < 0)
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400734 nfs_set_pgio_error(hdr, task->tk_status, hdr->args.offset);
Anna Schumaker0eecb212014-05-06 09:12:32 -0400735 else
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400736 hdr->rw_ops->rw_result(task, hdr);
Anna Schumaker0eecb212014-05-06 09:12:32 -0400737}
738
Anna Schumakeref2c4882014-05-06 09:12:36 -0400739/*
Anna Schumakeref2c4882014-05-06 09:12:36 -0400740 * Create an RPC task for the given read or write request and kick it.
741 * The page must have been locked by the caller.
742 *
743 * It may happen that the page we're passed is not marked dirty.
744 * This is the case if nfs_updatepage detects a conflicting request
745 * that has been written but not committed.
746 */
Weston Andros Adamsonf0cb9ab2014-05-15 11:56:52 -0400747int nfs_generic_pgio(struct nfs_pageio_descriptor *desc,
748 struct nfs_pgio_header *hdr)
Anna Schumakeref2c4882014-05-06 09:12:36 -0400749{
Peng Tao48d635f2014-11-10 08:35:35 +0800750 struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400751
Anna Schumakeref2c4882014-05-06 09:12:36 -0400752 struct nfs_page *req;
Weston Andros Adamsonbba5c182014-08-14 17:39:32 -0400753 struct page **pages,
754 *last_page;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400755 struct list_head *head = &mirror->pg_list;
Anna Schumakeref2c4882014-05-06 09:12:36 -0400756 struct nfs_commit_info cinfo;
Weston Andros Adamsonbba5c182014-08-14 17:39:32 -0400757 unsigned int pagecount, pageused;
Anna Schumakeref2c4882014-05-06 09:12:36 -0400758
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400759 pagecount = nfs_page_array_len(mirror->pg_base, mirror->pg_count);
Peng Tao2bff2282015-12-05 02:03:17 +0800760 if (!nfs_pgarray_set(&hdr->page_array, pagecount)) {
761 nfs_pgio_error(hdr);
762 desc->pg_error = -ENOMEM;
763 return desc->pg_error;
764 }
Anna Schumakeref2c4882014-05-06 09:12:36 -0400765
766 nfs_init_cinfo(&cinfo, desc->pg_inode, desc->pg_dreq);
Weston Andros Adamsond45f60c2014-06-09 11:48:35 -0400767 pages = hdr->page_array.pagevec;
Weston Andros Adamsonbba5c182014-08-14 17:39:32 -0400768 last_page = NULL;
769 pageused = 0;
Anna Schumakeref2c4882014-05-06 09:12:36 -0400770 while (!list_empty(head)) {
771 req = nfs_list_entry(head->next);
772 nfs_list_remove_request(req);
773 nfs_list_add_request(req, &hdr->pages);
Weston Andros Adamsonbba5c182014-08-14 17:39:32 -0400774
Weston Andros Adamsonbba5c182014-08-14 17:39:32 -0400775 if (!last_page || last_page != req->wb_page) {
Weston Andros Adamsonbba5c182014-08-14 17:39:32 -0400776 pageused++;
Trond Myklebustb8fb9c32014-10-13 10:56:12 -0400777 if (pageused > pagecount)
778 break;
779 *pages++ = last_page = req->wb_page;
Weston Andros Adamsonbba5c182014-08-14 17:39:32 -0400780 }
Anna Schumakeref2c4882014-05-06 09:12:36 -0400781 }
Peng Tao2bff2282015-12-05 02:03:17 +0800782 if (WARN_ON_ONCE(pageused != pagecount)) {
783 nfs_pgio_error(hdr);
784 desc->pg_error = -EINVAL;
785 return desc->pg_error;
786 }
Anna Schumakeref2c4882014-05-06 09:12:36 -0400787
788 if ((desc->pg_ioflags & FLUSH_COND_STABLE) &&
789 (desc->pg_moreio || nfs_reqs_to_commit(&cinfo)))
790 desc->pg_ioflags &= ~FLUSH_COND_STABLE;
791
792 /* Set up the argument struct */
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400793 nfs_pgio_rpcsetup(hdr, mirror->pg_count, 0, desc->pg_ioflags, &cinfo);
Anna Schumakeref2c4882014-05-06 09:12:36 -0400794 desc->pg_rpc_callops = &nfs_pgio_common_ops;
795 return 0;
796}
Weston Andros Adamsonf0cb9ab2014-05-15 11:56:52 -0400797EXPORT_SYMBOL_GPL(nfs_generic_pgio);
Anna Schumakeref2c4882014-05-06 09:12:36 -0400798
Anna Schumaker41d8d5b2014-05-06 09:12:40 -0400799static int nfs_generic_pg_pgios(struct nfs_pageio_descriptor *desc)
Anna Schumakercf485fc2014-05-06 09:12:39 -0400800{
Anna Schumakercf485fc2014-05-06 09:12:39 -0400801 struct nfs_pgio_header *hdr;
802 int ret;
803
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400804 hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
805 if (!hdr) {
Peng Tao2bff2282015-12-05 02:03:17 +0800806 desc->pg_error = -ENOMEM;
807 return desc->pg_error;
Anna Schumakercf485fc2014-05-06 09:12:39 -0400808 }
Weston Andros Adamson1e7f3a42014-06-09 11:48:33 -0400809 nfs_pgheader_init(desc, hdr, nfs_pgio_header_free);
Anna Schumakercf485fc2014-05-06 09:12:39 -0400810 ret = nfs_generic_pgio(desc, hdr);
811 if (ret == 0)
Weston Andros Adamson7f714722014-05-15 11:56:53 -0400812 ret = nfs_initiate_pgio(NFS_CLIENT(hdr->inode),
Peng Tao46a5ab42014-06-13 23:02:25 +0800813 hdr,
814 hdr->cred,
815 NFS_PROTO(hdr->inode),
Tom Haynesabde71f2014-06-09 13:12:20 -0700816 desc->pg_rpc_callops,
Weston Andros Adamson7f714722014-05-15 11:56:53 -0400817 desc->pg_ioflags, 0);
Anna Schumakercf485fc2014-05-06 09:12:39 -0400818 return ret;
819}
820
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400821/*
822 * nfs_pageio_setup_mirroring - determine if mirroring is to be used
823 * by calling the pg_get_mirror_count op
824 */
825static int nfs_pageio_setup_mirroring(struct nfs_pageio_descriptor *pgio,
826 struct nfs_page *req)
827{
828 int mirror_count = 1;
829
830 if (!pgio->pg_ops->pg_get_mirror_count)
831 return 0;
832
833 mirror_count = pgio->pg_ops->pg_get_mirror_count(pgio, req);
834
Peng Taod600ad12015-12-04 02:57:48 +0800835 if (pgio->pg_error < 0)
836 return pgio->pg_error;
837
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400838 if (!mirror_count || mirror_count > NFS_PAGEIO_DESCRIPTOR_MIRROR_MAX)
839 return -EINVAL;
840
841 if (WARN_ON_ONCE(!pgio->pg_mirrors_dynamic))
842 return -EINVAL;
843
844 pgio->pg_mirror_count = mirror_count;
845
846 return 0;
847}
848
849/*
850 * nfs_pageio_stop_mirroring - stop using mirroring (set mirror count to 1)
851 */
852void nfs_pageio_stop_mirroring(struct nfs_pageio_descriptor *pgio)
853{
854 pgio->pg_mirror_count = 1;
855 pgio->pg_mirror_idx = 0;
856}
857
858static void nfs_pageio_cleanup_mirroring(struct nfs_pageio_descriptor *pgio)
859{
860 pgio->pg_mirror_count = 1;
861 pgio->pg_mirror_idx = 0;
862 pgio->pg_mirrors = pgio->pg_mirrors_static;
863 kfree(pgio->pg_mirrors_dynamic);
864 pgio->pg_mirrors_dynamic = NULL;
865}
866
Trond Myklebust4109bb72013-09-06 11:09:38 -0400867static bool nfs_match_lock_context(const struct nfs_lock_context *l1,
868 const struct nfs_lock_context *l2)
869{
870 return l1->lockowner.l_owner == l2->lockowner.l_owner
871 && l1->lockowner.l_pid == l2->lockowner.l_pid;
872}
873
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400874/**
875 * nfs_can_coalesce_requests - test two requests for compatibility
876 * @prev: pointer to nfs_page
877 * @req: pointer to nfs_page
878 *
879 * The nfs_page structures 'prev' and 'req' are compared to ensure that the
880 * page data area they describe is contiguous, and that their RPC
881 * credentials, NFSv4 open state, and lockowners are the same.
882 *
883 * Return 'true' if this is the case, else return 'false'.
884 */
Benny Halevy18ad0a92011-05-25 21:03:56 +0300885static bool nfs_can_coalesce_requests(struct nfs_page *prev,
886 struct nfs_page *req,
887 struct nfs_pageio_descriptor *pgio)
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400888{
Weston Andros Adamsonb4fdac12014-05-15 11:56:43 -0400889 size_t size;
Jeff Layton5263e312015-01-16 15:05:55 -0500890 struct file_lock_context *flctx;
Weston Andros Adamsonb4fdac12014-05-15 11:56:43 -0400891
Weston Andros Adamsonab75e412014-05-15 11:56:44 -0400892 if (prev) {
893 if (!nfs_match_open_context(req->wb_context, prev->wb_context))
894 return false;
David Howells2b0143b2015-03-17 22:25:59 +0000895 flctx = d_inode(req->wb_context->dentry)->i_flctx;
Jeff Laytonbd61e0a2015-01-16 15:05:55 -0500896 if (flctx != NULL &&
897 !(list_empty_careful(&flctx->flc_posix) &&
898 list_empty_careful(&flctx->flc_flock)) &&
Jeff Layton5263e312015-01-16 15:05:55 -0500899 !nfs_match_lock_context(req->wb_lock_context,
900 prev->wb_lock_context))
901 return false;
Weston Andros Adamsonab75e412014-05-15 11:56:44 -0400902 if (req_offset(req) != req_offset(prev) + prev->wb_bytes)
903 return false;
Weston Andros Adamson78270e82014-08-14 17:39:33 -0400904 if (req->wb_page == prev->wb_page) {
905 if (req->wb_pgbase != prev->wb_pgbase + prev->wb_bytes)
906 return false;
907 } else {
908 if (req->wb_pgbase != 0 ||
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300909 prev->wb_pgbase + prev->wb_bytes != PAGE_SIZE)
Weston Andros Adamson78270e82014-08-14 17:39:33 -0400910 return false;
911 }
Weston Andros Adamsonab75e412014-05-15 11:56:44 -0400912 }
Weston Andros Adamsonb4fdac12014-05-15 11:56:43 -0400913 size = pgio->pg_ops->pg_test(pgio, prev, req);
Weston Andros Adamsonf0cb9ab2014-05-15 11:56:52 -0400914 WARN_ON_ONCE(size > req->wb_bytes);
915 if (size && size < req->wb_bytes)
916 req->wb_bytes = size;
Weston Andros Adamsonb4fdac12014-05-15 11:56:43 -0400917 return size > 0;
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400918}
919
920/**
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400921 * nfs_pageio_do_add_request - Attempt to coalesce a request into a page list.
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400922 * @desc: destination io descriptor
923 * @req: request
924 *
925 * Returns true if the request 'req' was successfully coalesced into the
926 * existing list of pages 'desc'.
927 */
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400928static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc,
929 struct nfs_page *req)
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400930{
Peng Tao48d635f2014-11-10 08:35:35 +0800931 struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400932
Weston Andros Adamsonab75e412014-05-15 11:56:44 -0400933 struct nfs_page *prev = NULL;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400934
935 if (mirror->pg_count != 0) {
936 prev = nfs_list_entry(mirror->pg_list.prev);
Boaz Harrosh5b36c7d2011-05-29 11:45:39 +0300937 } else {
Trond Myklebustd8007d42011-06-10 13:30:23 -0400938 if (desc->pg_ops->pg_init)
939 desc->pg_ops->pg_init(desc, req);
Peng Taod600ad12015-12-04 02:57:48 +0800940 if (desc->pg_error < 0)
941 return 0;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400942 mirror->pg_base = req->wb_pgbase;
Boaz Harrosh5b36c7d2011-05-29 11:45:39 +0300943 }
Weston Andros Adamsonab75e412014-05-15 11:56:44 -0400944 if (!nfs_can_coalesce_requests(prev, req, desc))
945 return 0;
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400946 nfs_list_remove_request(req);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400947 nfs_list_add_request(req, &mirror->pg_list);
948 mirror->pg_count += req->wb_bytes;
Trond Myklebustd8a5ad72007-04-02 18:48:28 -0400949 return 1;
950}
951
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400952/*
953 * Helper for nfs_pageio_add_request and nfs_pageio_complete
954 */
955static void nfs_pageio_doio(struct nfs_pageio_descriptor *desc)
956{
Peng Tao48d635f2014-11-10 08:35:35 +0800957 struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400958
959
960 if (!list_empty(&mirror->pg_list)) {
Trond Myklebust1751c362011-06-10 13:30:23 -0400961 int error = desc->pg_ops->pg_doio(desc);
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400962 if (error < 0)
963 desc->pg_error = error;
964 else
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400965 mirror->pg_bytes_written += mirror->pg_count;
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400966 }
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400967 if (list_empty(&mirror->pg_list)) {
968 mirror->pg_count = 0;
969 mirror->pg_base = 0;
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400970 }
971}
972
973/**
974 * nfs_pageio_add_request - Attempt to coalesce a request into a page list.
975 * @desc: destination io descriptor
976 * @req: request
977 *
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400978 * This may split a request into subrequests which are all part of the
979 * same page group.
980 *
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400981 * Returns true if the request 'req' was successfully coalesced into the
982 * existing list of pages 'desc'.
983 */
Trond Myklebustd9156f92011-07-12 13:42:02 -0400984static int __nfs_pageio_add_request(struct nfs_pageio_descriptor *desc,
Trond Myklebust8b09bee2007-04-02 18:48:28 -0400985 struct nfs_page *req)
Trond Myklebustbcb71bb2007-04-02 18:48:28 -0400986{
Peng Tao48d635f2014-11-10 08:35:35 +0800987 struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -0400988
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400989 struct nfs_page *subreq;
990 unsigned int bytes_left = 0;
991 unsigned int offset, pgbase;
992
Weston Andros Adamsonbfd484a2014-08-08 11:00:55 -0400993 nfs_page_group_lock(req, false);
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -0400994
995 subreq = req;
996 bytes_left = subreq->wb_bytes;
997 offset = subreq->wb_offset;
998 pgbase = subreq->wb_pgbase;
999
1000 do {
1001 if (!nfs_pageio_do_add_request(desc, subreq)) {
1002 /* make sure pg_test call(s) did nothing */
1003 WARN_ON_ONCE(subreq->wb_bytes != bytes_left);
1004 WARN_ON_ONCE(subreq->wb_offset != offset);
1005 WARN_ON_ONCE(subreq->wb_pgbase != pgbase);
1006
1007 nfs_page_group_unlock(req);
1008 desc->pg_moreio = 1;
1009 nfs_pageio_doio(desc);
1010 if (desc->pg_error < 0)
1011 return 0;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001012 if (mirror->pg_recoalesce)
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -04001013 return 0;
1014 /* retry add_request for this subreq */
Weston Andros Adamsonbfd484a2014-08-08 11:00:55 -04001015 nfs_page_group_lock(req, false);
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -04001016 continue;
1017 }
1018
1019 /* check for buggy pg_test call(s) */
1020 WARN_ON_ONCE(subreq->wb_bytes + subreq->wb_pgbase > PAGE_SIZE);
1021 WARN_ON_ONCE(subreq->wb_bytes > bytes_left);
1022 WARN_ON_ONCE(subreq->wb_bytes == 0);
1023
1024 bytes_left -= subreq->wb_bytes;
1025 offset += subreq->wb_bytes;
1026 pgbase += subreq->wb_bytes;
1027
1028 if (bytes_left) {
1029 subreq = nfs_create_request(req->wb_context,
1030 req->wb_page,
1031 subreq, pgbase, bytes_left);
Trond Myklebustc1109552014-05-29 11:38:15 -04001032 if (IS_ERR(subreq))
1033 goto err_ptr;
Weston Andros Adamson2bfc6e52014-05-15 11:56:45 -04001034 nfs_lock_request(subreq);
1035 subreq->wb_offset = offset;
1036 subreq->wb_index = req->wb_index;
1037 }
1038 } while (bytes_left > 0);
1039
1040 nfs_page_group_unlock(req);
Trond Myklebustbcb71bb2007-04-02 18:48:28 -04001041 return 1;
Trond Myklebustc1109552014-05-29 11:38:15 -04001042err_ptr:
1043 desc->pg_error = PTR_ERR(subreq);
1044 nfs_page_group_unlock(req);
1045 return 0;
Trond Myklebustbcb71bb2007-04-02 18:48:28 -04001046}
1047
Trond Myklebustd9156f92011-07-12 13:42:02 -04001048static int nfs_do_recoalesce(struct nfs_pageio_descriptor *desc)
1049{
Peng Tao48d635f2014-11-10 08:35:35 +08001050 struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
Trond Myklebustd9156f92011-07-12 13:42:02 -04001051 LIST_HEAD(head);
1052
1053 do {
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001054 list_splice_init(&mirror->pg_list, &head);
1055 mirror->pg_bytes_written -= mirror->pg_count;
1056 mirror->pg_count = 0;
1057 mirror->pg_base = 0;
1058 mirror->pg_recoalesce = 0;
1059
Trond Myklebustd9156f92011-07-12 13:42:02 -04001060 while (!list_empty(&head)) {
1061 struct nfs_page *req;
1062
1063 req = list_first_entry(&head, struct nfs_page, wb_list);
1064 nfs_list_remove_request(req);
1065 if (__nfs_pageio_add_request(desc, req))
1066 continue;
Trond Myklebust03d5eb62015-07-27 10:23:19 -04001067 if (desc->pg_error < 0) {
1068 list_splice_tail(&head, &mirror->pg_list);
1069 mirror->pg_recoalesce = 1;
Trond Myklebustd9156f92011-07-12 13:42:02 -04001070 return 0;
Trond Myklebust03d5eb62015-07-27 10:23:19 -04001071 }
Trond Myklebustd9156f92011-07-12 13:42:02 -04001072 break;
1073 }
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001074 } while (mirror->pg_recoalesce);
Trond Myklebustd9156f92011-07-12 13:42:02 -04001075 return 1;
1076}
1077
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001078static int nfs_pageio_add_request_mirror(struct nfs_pageio_descriptor *desc,
Trond Myklebustd9156f92011-07-12 13:42:02 -04001079 struct nfs_page *req)
1080{
1081 int ret;
1082
1083 do {
1084 ret = __nfs_pageio_add_request(desc, req);
1085 if (ret)
1086 break;
1087 if (desc->pg_error < 0)
1088 break;
1089 ret = nfs_do_recoalesce(desc);
1090 } while (ret);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001091
Trond Myklebustd9156f92011-07-12 13:42:02 -04001092 return ret;
1093}
1094
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001095int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc,
1096 struct nfs_page *req)
1097{
1098 u32 midx;
1099 unsigned int pgbase, offset, bytes;
1100 struct nfs_page *dupreq, *lastreq;
1101
1102 pgbase = req->wb_pgbase;
1103 offset = req->wb_offset;
1104 bytes = req->wb_bytes;
1105
1106 nfs_pageio_setup_mirroring(desc, req);
Peng Taod600ad12015-12-04 02:57:48 +08001107 if (desc->pg_error < 0)
Peng Taoc18b96a2015-12-05 01:59:56 +08001108 goto out_failed;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001109
1110 for (midx = 0; midx < desc->pg_mirror_count; midx++) {
1111 if (midx) {
1112 nfs_page_group_lock(req, false);
1113
1114 /* find the last request */
1115 for (lastreq = req->wb_head;
1116 lastreq->wb_this_page != req->wb_head;
1117 lastreq = lastreq->wb_this_page)
1118 ;
1119
1120 dupreq = nfs_create_request(req->wb_context,
1121 req->wb_page, lastreq, pgbase, bytes);
1122
1123 if (IS_ERR(dupreq)) {
1124 nfs_page_group_unlock(req);
Peng Taoc18b96a2015-12-05 01:59:56 +08001125 desc->pg_error = PTR_ERR(dupreq);
1126 goto out_failed;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001127 }
1128
1129 nfs_lock_request(dupreq);
1130 nfs_page_group_unlock(req);
1131 dupreq->wb_offset = offset;
1132 dupreq->wb_index = req->wb_index;
1133 } else
1134 dupreq = req;
1135
Peng Tao47af81f2014-11-10 08:35:34 +08001136 if (nfs_pgio_has_mirroring(desc))
1137 desc->pg_mirror_idx = midx;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001138 if (!nfs_pageio_add_request_mirror(desc, dupreq))
Peng Taoc18b96a2015-12-05 01:59:56 +08001139 goto out_failed;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001140 }
1141
1142 return 1;
Peng Taoc18b96a2015-12-05 01:59:56 +08001143
1144out_failed:
1145 /*
1146 * We might have failed before sending any reqs over wire.
Peng Tao2bff2282015-12-05 02:03:17 +08001147 * Clean up rest of the reqs in mirror pg_list.
Peng Taoc18b96a2015-12-05 01:59:56 +08001148 */
Peng Tao2bff2282015-12-05 02:03:17 +08001149 if (desc->pg_error) {
1150 struct nfs_pgio_mirror *mirror;
1151 void (*func)(struct list_head *);
1152
1153 /* remember fatal errors */
1154 if (nfs_error_is_fatal(desc->pg_error))
1155 mapping_set_error(desc->pg_inode->i_mapping,
1156 desc->pg_error);
1157
1158 func = desc->pg_completion_ops->error_cleanup;
1159 for (midx = 0; midx < desc->pg_mirror_count; midx++) {
1160 mirror = &desc->pg_mirrors[midx];
1161 func(&mirror->pg_list);
1162 }
1163 }
Peng Taoc18b96a2015-12-05 01:59:56 +08001164 return 0;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001165}
1166
1167/*
1168 * nfs_pageio_complete_mirror - Complete I/O on the current mirror of an
1169 * nfs_pageio_descriptor
1170 * @desc: pointer to io descriptor
Yijing Wangdfad7002015-06-18 19:37:13 +08001171 * @mirror_idx: pointer to mirror index
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001172 */
1173static void nfs_pageio_complete_mirror(struct nfs_pageio_descriptor *desc,
1174 u32 mirror_idx)
1175{
1176 struct nfs_pgio_mirror *mirror = &desc->pg_mirrors[mirror_idx];
1177 u32 restore_idx = desc->pg_mirror_idx;
1178
Peng Tao47af81f2014-11-10 08:35:34 +08001179 if (nfs_pgio_has_mirroring(desc))
1180 desc->pg_mirror_idx = mirror_idx;
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001181 for (;;) {
1182 nfs_pageio_doio(desc);
1183 if (!mirror->pg_recoalesce)
1184 break;
1185 if (!nfs_do_recoalesce(desc))
1186 break;
1187 }
1188 desc->pg_mirror_idx = restore_idx;
1189}
1190
Weston Andros Adamson53113ad2014-06-09 11:48:38 -04001191/*
1192 * nfs_pageio_resend - Transfer requests to new descriptor and resend
1193 * @hdr - the pgio header to move request from
1194 * @desc - the pageio descriptor to add requests to
1195 *
1196 * Try to move each request (nfs_page) from @hdr to @desc then attempt
1197 * to send them.
1198 *
1199 * Returns 0 on success and < 0 on error.
1200 */
1201int nfs_pageio_resend(struct nfs_pageio_descriptor *desc,
1202 struct nfs_pgio_header *hdr)
1203{
1204 LIST_HEAD(failed);
1205
1206 desc->pg_dreq = hdr->dreq;
1207 while (!list_empty(&hdr->pages)) {
1208 struct nfs_page *req = nfs_list_entry(hdr->pages.next);
1209
1210 nfs_list_remove_request(req);
1211 if (!nfs_pageio_add_request(desc, req))
1212 nfs_list_add_request(req, &failed);
1213 }
1214 nfs_pageio_complete(desc);
1215 if (!list_empty(&failed)) {
1216 list_move(&failed, &hdr->pages);
Peng Taod600ad12015-12-04 02:57:48 +08001217 return desc->pg_error < 0 ? desc->pg_error : -EIO;
Weston Andros Adamson53113ad2014-06-09 11:48:38 -04001218 }
1219 return 0;
1220}
1221EXPORT_SYMBOL_GPL(nfs_pageio_resend);
Trond Myklebustd8a5ad72007-04-02 18:48:28 -04001222
1223/**
Weston Andros Adamson2176bf42014-09-10 15:44:18 -04001224 * nfs_pageio_complete - Complete I/O then cleanup an nfs_pageio_descriptor
Trond Myklebustbcb71bb2007-04-02 18:48:28 -04001225 * @desc: pointer to io descriptor
1226 */
1227void nfs_pageio_complete(struct nfs_pageio_descriptor *desc)
1228{
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001229 u32 midx;
1230
1231 for (midx = 0; midx < desc->pg_mirror_count; midx++)
1232 nfs_pageio_complete_mirror(desc, midx);
Weston Andros Adamson2176bf42014-09-10 15:44:18 -04001233
1234 if (desc->pg_ops->pg_cleanup)
1235 desc->pg_ops->pg_cleanup(desc);
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001236 nfs_pageio_cleanup_mirroring(desc);
Trond Myklebustbcb71bb2007-04-02 18:48:28 -04001237}
1238
Trond Myklebust7fe7f842007-05-20 10:18:27 -04001239/**
1240 * nfs_pageio_cond_complete - Conditional I/O completion
1241 * @desc: pointer to io descriptor
1242 * @index: page index
1243 *
1244 * It is important to ensure that processes don't try to take locks
1245 * on non-contiguous ranges of pages as that might deadlock. This
1246 * function should be called before attempting to wait on a locked
1247 * nfs_page. It will complete the I/O if the page index 'index'
1248 * is not contiguous with the existing list of pages in 'desc'.
1249 */
1250void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *desc, pgoff_t index)
1251{
Weston Andros Adamsona7d42dd2014-09-19 10:55:07 -04001252 struct nfs_pgio_mirror *mirror;
1253 struct nfs_page *prev;
1254 u32 midx;
1255
1256 for (midx = 0; midx < desc->pg_mirror_count; midx++) {
1257 mirror = &desc->pg_mirrors[midx];
1258 if (!list_empty(&mirror->pg_list)) {
1259 prev = nfs_list_entry(mirror->pg_list.prev);
1260 if (index != prev->wb_index + 1)
1261 nfs_pageio_complete_mirror(desc, midx);
1262 }
Trond Myklebust7fe7f842007-05-20 10:18:27 -04001263 }
1264}
1265
David Howellsf7b422b2006-06-09 09:34:33 -04001266int __init nfs_init_nfspagecache(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001267{
1268 nfs_page_cachep = kmem_cache_create("nfs_page",
1269 sizeof(struct nfs_page),
1270 0, SLAB_HWCACHE_ALIGN,
Paul Mundt20c2df82007-07-20 10:11:58 +09001271 NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001272 if (nfs_page_cachep == NULL)
1273 return -ENOMEM;
1274
1275 return 0;
1276}
1277
David Brownell266bee82006-06-27 12:59:15 -07001278void nfs_destroy_nfspagecache(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001279{
Alexey Dobriyan1a1d92c2006-09-27 01:49:40 -07001280 kmem_cache_destroy(nfs_page_cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281}
1282
Anna Schumakeref2c4882014-05-06 09:12:36 -04001283static const struct rpc_call_ops nfs_pgio_common_ops = {
Anna Schumaker6f92fa42014-05-06 09:12:33 -04001284 .rpc_call_prepare = nfs_pgio_prepare,
1285 .rpc_call_done = nfs_pgio_result,
1286 .rpc_release = nfs_pgio_release,
1287};
Anna Schumaker41d8d5b2014-05-06 09:12:40 -04001288
1289const struct nfs_pageio_ops nfs_pgio_rw_ops = {
1290 .pg_test = nfs_generic_pg_test,
1291 .pg_doio = nfs_generic_pg_pgios,
1292};