4 * Write file data over NFS.
6 * Copyright (C) 1996, 1997, Olaf Kirch <okir@monad.swb.de>
9 #include <linux/types.h>
10 #include <linux/slab.h>
12 #include <linux/pagemap.h>
13 #include <linux/file.h>
14 #include <linux/writeback.h>
15 #include <linux/swap.h>
16 #include <linux/migrate.h>
18 #include <linux/sunrpc/clnt.h>
19 #include <linux/nfs_fs.h>
20 #include <linux/nfs_mount.h>
21 #include <linux/nfs_page.h>
22 #include <linux/backing-dev.h>
24 #include <asm/uaccess.h>
26 #include "delegation.h"
33 #define NFSDBG_FACILITY NFSDBG_PAGECACHE
35 #define MIN_POOL_WRITE (32)
36 #define MIN_POOL_COMMIT (4)
39 * Local function declarations
41 static void nfs_pageio_init_write(struct nfs_pageio_descriptor
*desc
,
42 struct inode
*inode
, int ioflags
);
43 static void nfs_redirty_request(struct nfs_page
*req
);
44 static const struct rpc_call_ops nfs_write_partial_ops
;
45 static const struct rpc_call_ops nfs_write_full_ops
;
46 static const struct rpc_call_ops nfs_commit_ops
;
48 static struct kmem_cache
*nfs_wdata_cachep
;
49 static mempool_t
*nfs_wdata_mempool
;
50 static mempool_t
*nfs_commit_mempool
;
52 struct nfs_write_data
*nfs_commitdata_alloc(void)
54 struct nfs_write_data
*p
= mempool_alloc(nfs_commit_mempool
, GFP_NOFS
);
57 memset(p
, 0, sizeof(*p
));
58 INIT_LIST_HEAD(&p
->pages
);
62 EXPORT_SYMBOL_GPL(nfs_commitdata_alloc
);
64 void nfs_commit_free(struct nfs_write_data
*p
)
66 if (p
&& (p
->pagevec
!= &p
->page_array
[0]))
68 mempool_free(p
, nfs_commit_mempool
);
70 EXPORT_SYMBOL_GPL(nfs_commit_free
);
72 struct nfs_write_data
*nfs_writedata_alloc(unsigned int pagecount
)
74 struct nfs_write_data
*p
= mempool_alloc(nfs_wdata_mempool
, GFP_NOFS
);
77 memset(p
, 0, sizeof(*p
));
78 INIT_LIST_HEAD(&p
->pages
);
79 p
->npages
= pagecount
;
80 if (pagecount
<= ARRAY_SIZE(p
->page_array
))
81 p
->pagevec
= p
->page_array
;
83 p
->pagevec
= kcalloc(pagecount
, sizeof(struct page
*), GFP_NOFS
);
85 mempool_free(p
, nfs_wdata_mempool
);
93 void nfs_writedata_free(struct nfs_write_data
*p
)
95 if (p
&& (p
->pagevec
!= &p
->page_array
[0]))
97 mempool_free(p
, nfs_wdata_mempool
);
100 static void nfs_writedata_release(struct nfs_write_data
*wdata
)
102 put_lseg(wdata
->lseg
);
103 put_nfs_open_context(wdata
->args
.context
);
104 nfs_writedata_free(wdata
);
107 static void nfs_context_set_write_error(struct nfs_open_context
*ctx
, int error
)
111 set_bit(NFS_CONTEXT_ERROR_WRITE
, &ctx
->flags
);
114 static struct nfs_page
*nfs_page_find_request_locked(struct page
*page
)
116 struct nfs_page
*req
= NULL
;
118 if (PagePrivate(page
)) {
119 req
= (struct nfs_page
*)page_private(page
);
121 kref_get(&req
->wb_kref
);
126 static struct nfs_page
*nfs_page_find_request(struct page
*page
)
128 struct inode
*inode
= page
->mapping
->host
;
129 struct nfs_page
*req
= NULL
;
131 spin_lock(&inode
->i_lock
);
132 req
= nfs_page_find_request_locked(page
);
133 spin_unlock(&inode
->i_lock
);
137 /* Adjust the file length if we're writing beyond the end */
138 static void nfs_grow_file(struct page
*page
, unsigned int offset
, unsigned int count
)
140 struct inode
*inode
= page
->mapping
->host
;
144 spin_lock(&inode
->i_lock
);
145 i_size
= i_size_read(inode
);
146 end_index
= (i_size
- 1) >> PAGE_CACHE_SHIFT
;
147 if (i_size
> 0 && page
->index
< end_index
)
149 end
= ((loff_t
)page
->index
<< PAGE_CACHE_SHIFT
) + ((loff_t
)offset
+count
);
152 i_size_write(inode
, end
);
153 nfs_inc_stats(inode
, NFSIOS_EXTENDWRITE
);
155 spin_unlock(&inode
->i_lock
);
158 /* A writeback failed: mark the page as bad, and invalidate the page cache */
159 static void nfs_set_pageerror(struct page
*page
)
162 nfs_zap_mapping(page
->mapping
->host
, page
->mapping
);
165 /* We can set the PG_uptodate flag if we see that a write request
166 * covers the full page.
168 static void nfs_mark_uptodate(struct page
*page
, unsigned int base
, unsigned int count
)
170 if (PageUptodate(page
))
174 if (count
!= nfs_page_length(page
))
176 SetPageUptodate(page
);
179 static int wb_priority(struct writeback_control
*wbc
)
181 if (wbc
->for_reclaim
)
182 return FLUSH_HIGHPRI
| FLUSH_STABLE
;
183 if (wbc
->for_kupdate
|| wbc
->for_background
)
184 return FLUSH_LOWPRI
| FLUSH_COND_STABLE
;
185 return FLUSH_COND_STABLE
;
189 * NFS congestion control
192 int nfs_congestion_kb
;
194 #define NFS_CONGESTION_ON_THRESH (nfs_congestion_kb >> (PAGE_SHIFT-10))
195 #define NFS_CONGESTION_OFF_THRESH \
196 (NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2))
198 static int nfs_set_page_writeback(struct page
*page
)
200 int ret
= test_set_page_writeback(page
);
203 struct inode
*inode
= page
->mapping
->host
;
204 struct nfs_server
*nfss
= NFS_SERVER(inode
);
206 page_cache_get(page
);
207 if (atomic_long_inc_return(&nfss
->writeback
) >
208 NFS_CONGESTION_ON_THRESH
) {
209 set_bdi_congested(&nfss
->backing_dev_info
,
216 static void nfs_end_page_writeback(struct page
*page
)
218 struct inode
*inode
= page
->mapping
->host
;
219 struct nfs_server
*nfss
= NFS_SERVER(inode
);
221 end_page_writeback(page
);
222 page_cache_release(page
);
223 if (atomic_long_dec_return(&nfss
->writeback
) < NFS_CONGESTION_OFF_THRESH
)
224 clear_bdi_congested(&nfss
->backing_dev_info
, BLK_RW_ASYNC
);
227 static struct nfs_page
*nfs_find_and_lock_request(struct page
*page
, bool nonblock
)
229 struct inode
*inode
= page
->mapping
->host
;
230 struct nfs_page
*req
;
233 spin_lock(&inode
->i_lock
);
235 req
= nfs_page_find_request_locked(page
);
238 if (nfs_set_page_tag_locked(req
))
240 /* Note: If we hold the page lock, as is the case in nfs_writepage,
241 * then the call to nfs_set_page_tag_locked() will always
242 * succeed provided that someone hasn't already marked the
243 * request as dirty (in which case we don't care).
245 spin_unlock(&inode
->i_lock
);
247 ret
= nfs_wait_on_request(req
);
250 nfs_release_request(req
);
253 spin_lock(&inode
->i_lock
);
255 spin_unlock(&inode
->i_lock
);
260 * Find an associated nfs write request, and prepare to flush it out
261 * May return an error if the user signalled nfs_wait_on_request().
263 static int nfs_page_async_flush(struct nfs_pageio_descriptor
*pgio
,
264 struct page
*page
, bool nonblock
)
266 struct nfs_page
*req
;
269 req
= nfs_find_and_lock_request(page
, nonblock
);
276 ret
= nfs_set_page_writeback(page
);
278 BUG_ON(test_bit(PG_CLEAN
, &req
->wb_flags
));
280 if (!nfs_pageio_add_request(pgio
, req
)) {
281 nfs_redirty_request(req
);
282 ret
= pgio
->pg_error
;
288 static int nfs_do_writepage(struct page
*page
, struct writeback_control
*wbc
, struct nfs_pageio_descriptor
*pgio
)
290 struct inode
*inode
= page
->mapping
->host
;
293 nfs_inc_stats(inode
, NFSIOS_VFSWRITEPAGE
);
294 nfs_add_stats(inode
, NFSIOS_WRITEPAGES
, 1);
296 nfs_pageio_cond_complete(pgio
, page
->index
);
297 ret
= nfs_page_async_flush(pgio
, page
, wbc
->sync_mode
== WB_SYNC_NONE
);
298 if (ret
== -EAGAIN
) {
299 redirty_page_for_writepage(wbc
, page
);
306 * Write an mmapped page to the server.
308 static int nfs_writepage_locked(struct page
*page
, struct writeback_control
*wbc
)
310 struct nfs_pageio_descriptor pgio
;
313 nfs_pageio_init_write(&pgio
, page
->mapping
->host
, wb_priority(wbc
));
314 err
= nfs_do_writepage(page
, wbc
, &pgio
);
315 nfs_pageio_complete(&pgio
);
318 if (pgio
.pg_error
< 0)
319 return pgio
.pg_error
;
323 int nfs_writepage(struct page
*page
, struct writeback_control
*wbc
)
327 ret
= nfs_writepage_locked(page
, wbc
);
332 static int nfs_writepages_callback(struct page
*page
, struct writeback_control
*wbc
, void *data
)
336 ret
= nfs_do_writepage(page
, wbc
, data
);
341 int nfs_writepages(struct address_space
*mapping
, struct writeback_control
*wbc
)
343 struct inode
*inode
= mapping
->host
;
344 unsigned long *bitlock
= &NFS_I(inode
)->flags
;
345 struct nfs_pageio_descriptor pgio
;
348 /* Stop dirtying of new pages while we sync */
349 err
= wait_on_bit_lock(bitlock
, NFS_INO_FLUSHING
,
350 nfs_wait_bit_killable
, TASK_KILLABLE
);
354 nfs_inc_stats(inode
, NFSIOS_VFSWRITEPAGES
);
356 nfs_pageio_init_write(&pgio
, inode
, wb_priority(wbc
));
357 err
= write_cache_pages(mapping
, wbc
, nfs_writepages_callback
, &pgio
);
358 nfs_pageio_complete(&pgio
);
360 clear_bit_unlock(NFS_INO_FLUSHING
, bitlock
);
361 smp_mb__after_clear_bit();
362 wake_up_bit(bitlock
, NFS_INO_FLUSHING
);
375 * Insert a write request into an inode
377 static int nfs_inode_add_request(struct inode
*inode
, struct nfs_page
*req
)
379 struct nfs_inode
*nfsi
= NFS_I(inode
);
382 error
= radix_tree_preload(GFP_NOFS
);
386 /* Lock the request! */
387 nfs_lock_request_dontget(req
);
389 spin_lock(&inode
->i_lock
);
390 error
= radix_tree_insert(&nfsi
->nfs_page_tree
, req
->wb_index
, req
);
392 if (!nfsi
->npages
&& nfs_have_delegation(inode
, FMODE_WRITE
))
394 set_bit(PG_MAPPED
, &req
->wb_flags
);
395 SetPagePrivate(req
->wb_page
);
396 set_page_private(req
->wb_page
, (unsigned long)req
);
398 kref_get(&req
->wb_kref
);
399 radix_tree_tag_set(&nfsi
->nfs_page_tree
, req
->wb_index
,
400 NFS_PAGE_TAG_LOCKED
);
401 spin_unlock(&inode
->i_lock
);
402 radix_tree_preload_end();
408 * Remove a write request from an inode
410 static void nfs_inode_remove_request(struct nfs_page
*req
)
412 struct inode
*inode
= req
->wb_context
->path
.dentry
->d_inode
;
413 struct nfs_inode
*nfsi
= NFS_I(inode
);
415 BUG_ON (!NFS_WBACK_BUSY(req
));
417 spin_lock(&inode
->i_lock
);
418 set_page_private(req
->wb_page
, 0);
419 ClearPagePrivate(req
->wb_page
);
420 clear_bit(PG_MAPPED
, &req
->wb_flags
);
421 radix_tree_delete(&nfsi
->nfs_page_tree
, req
->wb_index
);
423 spin_unlock(&inode
->i_lock
);
424 nfs_release_request(req
);
428 nfs_mark_request_dirty(struct nfs_page
*req
)
430 __set_page_dirty_nobuffers(req
->wb_page
);
431 __mark_inode_dirty(req
->wb_page
->mapping
->host
, I_DIRTY_DATASYNC
);
434 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
436 * Add a request to the inode's commit list.
439 nfs_mark_request_commit(struct nfs_page
*req
, struct pnfs_layout_segment
*lseg
)
441 struct inode
*inode
= req
->wb_context
->path
.dentry
->d_inode
;
442 struct nfs_inode
*nfsi
= NFS_I(inode
);
444 spin_lock(&inode
->i_lock
);
445 set_bit(PG_CLEAN
, &(req
)->wb_flags
);
446 radix_tree_tag_set(&nfsi
->nfs_page_tree
,
448 NFS_PAGE_TAG_COMMIT
);
450 spin_unlock(&inode
->i_lock
);
451 pnfs_mark_request_commit(req
, lseg
);
452 inc_zone_page_state(req
->wb_page
, NR_UNSTABLE_NFS
);
453 inc_bdi_stat(req
->wb_page
->mapping
->backing_dev_info
, BDI_RECLAIMABLE
);
454 __mark_inode_dirty(inode
, I_DIRTY_DATASYNC
);
458 nfs_clear_request_commit(struct nfs_page
*req
)
460 struct page
*page
= req
->wb_page
;
462 if (test_and_clear_bit(PG_CLEAN
, &(req
)->wb_flags
)) {
463 dec_zone_page_state(page
, NR_UNSTABLE_NFS
);
464 dec_bdi_stat(page
->mapping
->backing_dev_info
, BDI_RECLAIMABLE
);
471 int nfs_write_need_commit(struct nfs_write_data
*data
)
473 if (data
->verf
.committed
== NFS_DATA_SYNC
)
474 return data
->lseg
== NULL
;
476 return data
->verf
.committed
!= NFS_FILE_SYNC
;
480 int nfs_reschedule_unstable_write(struct nfs_page
*req
,
481 struct nfs_write_data
*data
)
483 if (test_and_clear_bit(PG_NEED_COMMIT
, &req
->wb_flags
)) {
484 nfs_mark_request_commit(req
, data
->lseg
);
487 if (test_and_clear_bit(PG_NEED_RESCHED
, &req
->wb_flags
)) {
488 nfs_mark_request_dirty(req
);
495 nfs_mark_request_commit(struct nfs_page
*req
, struct pnfs_layout_segment
*lseg
)
500 nfs_clear_request_commit(struct nfs_page
*req
)
506 int nfs_write_need_commit(struct nfs_write_data
*data
)
512 int nfs_reschedule_unstable_write(struct nfs_page
*req
,
513 struct nfs_write_data
*data
)
519 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
521 nfs_need_commit(struct nfs_inode
*nfsi
)
523 return radix_tree_tagged(&nfsi
->nfs_page_tree
, NFS_PAGE_TAG_COMMIT
);
527 * nfs_scan_commit - Scan an inode for commit requests
528 * @inode: NFS inode to scan
529 * @dst: destination list
530 * @idx_start: lower bound of page->index to scan.
531 * @npages: idx_start + npages sets the upper bound to scan.
533 * Moves requests from the inode's 'commit' request list.
534 * The requests are *not* checked to ensure that they form a contiguous set.
537 nfs_scan_commit(struct inode
*inode
, struct list_head
*dst
, pgoff_t idx_start
, unsigned int npages
)
539 struct nfs_inode
*nfsi
= NFS_I(inode
);
542 if (!nfs_need_commit(nfsi
))
545 spin_lock(&inode
->i_lock
);
546 ret
= nfs_scan_list(nfsi
, dst
, idx_start
, npages
, NFS_PAGE_TAG_COMMIT
);
548 nfsi
->ncommit
-= ret
;
549 spin_unlock(&inode
->i_lock
);
551 if (nfs_need_commit(NFS_I(inode
)))
552 __mark_inode_dirty(inode
, I_DIRTY_DATASYNC
);
557 static inline int nfs_need_commit(struct nfs_inode
*nfsi
)
562 static inline int nfs_scan_commit(struct inode
*inode
, struct list_head
*dst
, pgoff_t idx_start
, unsigned int npages
)
569 * Search for an existing write request, and attempt to update
570 * it to reflect a new dirty region on a given page.
572 * If the attempt fails, then the existing request is flushed out
575 static struct nfs_page
*nfs_try_to_update_request(struct inode
*inode
,
580 struct nfs_page
*req
;
585 if (!PagePrivate(page
))
588 end
= offset
+ bytes
;
589 spin_lock(&inode
->i_lock
);
592 req
= nfs_page_find_request_locked(page
);
596 rqend
= req
->wb_offset
+ req
->wb_bytes
;
598 * Tell the caller to flush out the request if
599 * the offsets are non-contiguous.
600 * Note: nfs_flush_incompatible() will already
601 * have flushed out requests having wrong owners.
604 || end
< req
->wb_offset
)
607 if (nfs_set_page_tag_locked(req
))
610 /* The request is locked, so wait and then retry */
611 spin_unlock(&inode
->i_lock
);
612 error
= nfs_wait_on_request(req
);
613 nfs_release_request(req
);
616 spin_lock(&inode
->i_lock
);
619 if (nfs_clear_request_commit(req
) &&
620 radix_tree_tag_clear(&NFS_I(inode
)->nfs_page_tree
,
621 req
->wb_index
, NFS_PAGE_TAG_COMMIT
) != NULL
) {
622 NFS_I(inode
)->ncommit
--;
623 pnfs_clear_request_commit(req
);
626 /* Okay, the request matches. Update the region */
627 if (offset
< req
->wb_offset
) {
628 req
->wb_offset
= offset
;
629 req
->wb_pgbase
= offset
;
632 req
->wb_bytes
= end
- req
->wb_offset
;
634 req
->wb_bytes
= rqend
- req
->wb_offset
;
636 spin_unlock(&inode
->i_lock
);
639 spin_unlock(&inode
->i_lock
);
640 nfs_release_request(req
);
641 error
= nfs_wb_page(inode
, page
);
643 return ERR_PTR(error
);
647 * Try to update an existing write request, or create one if there is none.
649 * Note: Should always be called with the Page Lock held to prevent races
650 * if we have to add a new request. Also assumes that the caller has
651 * already called nfs_flush_incompatible() if necessary.
653 static struct nfs_page
* nfs_setup_write_request(struct nfs_open_context
* ctx
,
654 struct page
*page
, unsigned int offset
, unsigned int bytes
)
656 struct inode
*inode
= page
->mapping
->host
;
657 struct nfs_page
*req
;
660 req
= nfs_try_to_update_request(inode
, page
, offset
, bytes
);
663 req
= nfs_create_request(ctx
, inode
, page
, offset
, bytes
);
666 error
= nfs_inode_add_request(inode
, req
);
668 nfs_release_request(req
);
669 req
= ERR_PTR(error
);
675 static int nfs_writepage_setup(struct nfs_open_context
*ctx
, struct page
*page
,
676 unsigned int offset
, unsigned int count
)
678 struct nfs_page
*req
;
680 req
= nfs_setup_write_request(ctx
, page
, offset
, count
);
683 /* Update file length */
684 nfs_grow_file(page
, offset
, count
);
685 nfs_mark_uptodate(page
, req
->wb_pgbase
, req
->wb_bytes
);
686 nfs_mark_request_dirty(req
);
687 nfs_clear_page_tag_locked(req
);
691 int nfs_flush_incompatible(struct file
*file
, struct page
*page
)
693 struct nfs_open_context
*ctx
= nfs_file_open_context(file
);
694 struct nfs_page
*req
;
695 int do_flush
, status
;
697 * Look for a request corresponding to this page. If there
698 * is one, and it belongs to another file, we flush it out
699 * before we try to copy anything into the page. Do this
700 * due to the lack of an ACCESS-type call in NFSv2.
701 * Also do the same if we find a request from an existing
705 req
= nfs_page_find_request(page
);
708 do_flush
= req
->wb_page
!= page
|| req
->wb_context
!= ctx
||
709 req
->wb_lock_context
->lockowner
!= current
->files
||
710 req
->wb_lock_context
->pid
!= current
->tgid
;
711 nfs_release_request(req
);
714 status
= nfs_wb_page(page
->mapping
->host
, page
);
715 } while (status
== 0);
720 * If the page cache is marked as unsafe or invalid, then we can't rely on
721 * the PageUptodate() flag. In this case, we will need to turn off
722 * write optimisations that depend on the page contents being correct.
724 static int nfs_write_pageuptodate(struct page
*page
, struct inode
*inode
)
726 return PageUptodate(page
) &&
727 !(NFS_I(inode
)->cache_validity
& (NFS_INO_REVAL_PAGECACHE
|NFS_INO_INVALID_DATA
));
731 * Update and possibly write a cached page of an NFS file.
733 * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad
734 * things with a page scheduled for an RPC call (e.g. invalidate it).
736 int nfs_updatepage(struct file
*file
, struct page
*page
,
737 unsigned int offset
, unsigned int count
)
739 struct nfs_open_context
*ctx
= nfs_file_open_context(file
);
740 struct inode
*inode
= page
->mapping
->host
;
743 nfs_inc_stats(inode
, NFSIOS_VFSUPDATEPAGE
);
745 dprintk("NFS: nfs_updatepage(%s/%s %d@%lld)\n",
746 file
->f_path
.dentry
->d_parent
->d_name
.name
,
747 file
->f_path
.dentry
->d_name
.name
, count
,
748 (long long)(page_offset(page
) + offset
));
750 /* If we're not using byte range locks, and we know the page
751 * is up to date, it may be more efficient to extend the write
752 * to cover the entire page in order to avoid fragmentation
755 if (nfs_write_pageuptodate(page
, inode
) &&
756 inode
->i_flock
== NULL
&&
757 !(file
->f_flags
& O_DSYNC
)) {
758 count
= max(count
+ offset
, nfs_page_length(page
));
762 status
= nfs_writepage_setup(ctx
, page
, offset
, count
);
764 nfs_set_pageerror(page
);
766 dprintk("NFS: nfs_updatepage returns %d (isize %lld)\n",
767 status
, (long long)i_size_read(inode
));
771 static void nfs_writepage_release(struct nfs_page
*req
,
772 struct nfs_write_data
*data
)
774 struct page
*page
= req
->wb_page
;
776 if (PageError(req
->wb_page
) || !nfs_reschedule_unstable_write(req
, data
))
777 nfs_inode_remove_request(req
);
778 nfs_clear_page_tag_locked(req
);
779 nfs_end_page_writeback(page
);
782 static int flush_task_priority(int how
)
784 switch (how
& (FLUSH_HIGHPRI
|FLUSH_LOWPRI
)) {
786 return RPC_PRIORITY_HIGH
;
788 return RPC_PRIORITY_LOW
;
790 return RPC_PRIORITY_NORMAL
;
793 int nfs_initiate_write(struct nfs_write_data
*data
,
794 struct rpc_clnt
*clnt
,
795 const struct rpc_call_ops
*call_ops
,
798 struct inode
*inode
= data
->inode
;
799 int priority
= flush_task_priority(how
);
800 struct rpc_task
*task
;
801 struct rpc_message msg
= {
802 .rpc_argp
= &data
->args
,
803 .rpc_resp
= &data
->res
,
804 .rpc_cred
= data
->cred
,
806 struct rpc_task_setup task_setup_data
= {
810 .callback_ops
= call_ops
,
811 .callback_data
= data
,
812 .workqueue
= nfsiod_workqueue
,
813 .flags
= RPC_TASK_ASYNC
,
814 .priority
= priority
,
818 /* Set up the initial task struct. */
819 NFS_PROTO(inode
)->write_setup(data
, &msg
);
821 dprintk("NFS: %5u initiated write call "
822 "(req %s/%lld, %u bytes @ offset %llu)\n",
825 (long long)NFS_FILEID(inode
),
827 (unsigned long long)data
->args
.offset
);
829 task
= rpc_run_task(&task_setup_data
);
834 if (how
& FLUSH_SYNC
) {
835 ret
= rpc_wait_for_completion_task(task
);
837 ret
= task
->tk_status
;
843 EXPORT_SYMBOL_GPL(nfs_initiate_write
);
846 * Set up the argument/result storage required for the RPC call.
848 static int nfs_write_rpcsetup(struct nfs_page
*req
,
849 struct nfs_write_data
*data
,
850 const struct rpc_call_ops
*call_ops
,
851 unsigned int count
, unsigned int offset
,
852 struct pnfs_layout_segment
*lseg
,
855 struct inode
*inode
= req
->wb_context
->path
.dentry
->d_inode
;
857 /* Set up the RPC argument and reply structs
858 * NB: take care not to mess about with data->commit et al. */
861 data
->inode
= inode
= req
->wb_context
->path
.dentry
->d_inode
;
862 data
->cred
= req
->wb_context
->cred
;
863 data
->lseg
= get_lseg(lseg
);
865 data
->args
.fh
= NFS_FH(inode
);
866 data
->args
.offset
= req_offset(req
) + offset
;
867 /* pnfs_set_layoutcommit needs this */
868 data
->mds_offset
= data
->args
.offset
;
869 data
->args
.pgbase
= req
->wb_pgbase
+ offset
;
870 data
->args
.pages
= data
->pagevec
;
871 data
->args
.count
= count
;
872 data
->args
.context
= get_nfs_open_context(req
->wb_context
);
873 data
->args
.lock_context
= req
->wb_lock_context
;
874 data
->args
.stable
= NFS_UNSTABLE
;
875 if (how
& (FLUSH_STABLE
| FLUSH_COND_STABLE
)) {
876 data
->args
.stable
= NFS_DATA_SYNC
;
877 if (!nfs_need_commit(NFS_I(inode
)))
878 data
->args
.stable
= NFS_FILE_SYNC
;
881 data
->res
.fattr
= &data
->fattr
;
882 data
->res
.count
= count
;
883 data
->res
.verf
= &data
->verf
;
884 nfs_fattr_init(&data
->fattr
);
887 (pnfs_try_to_write_data(data
, call_ops
, how
) == PNFS_ATTEMPTED
))
890 return nfs_initiate_write(data
, NFS_CLIENT(inode
), call_ops
, how
);
893 /* If a nfs_flush_* function fails, it should remove reqs from @head and
894 * call this on each, which will prepare them to be retried on next
895 * writeback using standard nfs.
897 static void nfs_redirty_request(struct nfs_page
*req
)
899 struct page
*page
= req
->wb_page
;
901 nfs_mark_request_dirty(req
);
902 nfs_clear_page_tag_locked(req
);
903 nfs_end_page_writeback(page
);
907 * Generate multiple small requests to write out a single
908 * contiguous dirty area on one page.
910 static int nfs_flush_multi(struct nfs_pageio_descriptor
*desc
)
912 struct nfs_page
*req
= nfs_list_entry(desc
->pg_list
.next
);
913 struct page
*page
= req
->wb_page
;
914 struct nfs_write_data
*data
;
915 size_t wsize
= NFS_SERVER(desc
->pg_inode
)->wsize
, nbytes
;
919 struct pnfs_layout_segment
*lseg
;
922 nfs_list_remove_request(req
);
924 if ((desc
->pg_ioflags
& FLUSH_COND_STABLE
) &&
925 (desc
->pg_moreio
|| NFS_I(desc
->pg_inode
)->ncommit
||
926 desc
->pg_count
> wsize
))
927 desc
->pg_ioflags
&= ~FLUSH_COND_STABLE
;
930 nbytes
= desc
->pg_count
;
932 size_t len
= min(nbytes
, wsize
);
934 data
= nfs_writedata_alloc(1);
937 list_add(&data
->pages
, &list
);
940 } while (nbytes
!= 0);
941 atomic_set(&req
->wb_complete
, requests
);
943 BUG_ON(desc
->pg_lseg
);
944 lseg
= pnfs_update_layout(desc
->pg_inode
, req
->wb_context
,
945 req_offset(req
), desc
->pg_count
,
946 IOMODE_RW
, GFP_NOFS
);
947 ClearPageError(page
);
949 nbytes
= desc
->pg_count
;
953 data
= list_entry(list
.next
, struct nfs_write_data
, pages
);
954 list_del_init(&data
->pages
);
956 data
->pagevec
[0] = page
;
960 ret2
= nfs_write_rpcsetup(req
, data
, &nfs_write_partial_ops
,
961 wsize
, offset
, lseg
, desc
->pg_ioflags
);
966 } while (nbytes
!= 0);
969 desc
->pg_lseg
= NULL
;
973 while (!list_empty(&list
)) {
974 data
= list_entry(list
.next
, struct nfs_write_data
, pages
);
975 list_del(&data
->pages
);
976 nfs_writedata_free(data
);
978 nfs_redirty_request(req
);
983 * Create an RPC task for the given write request and kick it.
984 * The page must have been locked by the caller.
986 * It may happen that the page we're passed is not marked dirty.
987 * This is the case if nfs_updatepage detects a conflicting request
988 * that has been written but not committed.
990 static int nfs_flush_one(struct nfs_pageio_descriptor
*desc
)
992 struct nfs_page
*req
;
994 struct nfs_write_data
*data
;
995 struct list_head
*head
= &desc
->pg_list
;
996 struct pnfs_layout_segment
*lseg
= desc
->pg_lseg
;
999 data
= nfs_writedata_alloc(nfs_page_array_len(desc
->pg_base
,
1002 while (!list_empty(head
)) {
1003 req
= nfs_list_entry(head
->next
);
1004 nfs_list_remove_request(req
);
1005 nfs_redirty_request(req
);
1010 pages
= data
->pagevec
;
1011 while (!list_empty(head
)) {
1012 req
= nfs_list_entry(head
->next
);
1013 nfs_list_remove_request(req
);
1014 nfs_list_add_request(req
, &data
->pages
);
1015 ClearPageError(req
->wb_page
);
1016 *pages
++ = req
->wb_page
;
1018 req
= nfs_list_entry(data
->pages
.next
);
1019 if ((!lseg
) && list_is_singular(&data
->pages
))
1020 lseg
= pnfs_update_layout(desc
->pg_inode
, req
->wb_context
,
1021 req_offset(req
), desc
->pg_count
,
1022 IOMODE_RW
, GFP_NOFS
);
1024 if ((desc
->pg_ioflags
& FLUSH_COND_STABLE
) &&
1025 (desc
->pg_moreio
|| NFS_I(desc
->pg_inode
)->ncommit
))
1026 desc
->pg_ioflags
&= ~FLUSH_COND_STABLE
;
1028 /* Set up the argument struct */
1029 ret
= nfs_write_rpcsetup(req
, data
, &nfs_write_full_ops
, desc
->pg_count
, 0, lseg
, desc
->pg_ioflags
);
1031 put_lseg(lseg
); /* Cleans any gotten in ->pg_test */
1032 desc
->pg_lseg
= NULL
;
1036 int nfs_generic_pg_writepages(struct nfs_pageio_descriptor
*desc
)
1038 if (desc
->pg_bsize
< PAGE_CACHE_SIZE
)
1039 return nfs_flush_multi(desc
);
1040 return nfs_flush_one(desc
);
1042 EXPORT_SYMBOL_GPL(nfs_generic_pg_writepages
);
1044 static const struct nfs_pageio_ops nfs_pageio_write_ops
= {
1045 .pg_test
= nfs_generic_pg_test
,
1046 .pg_doio
= nfs_generic_pg_writepages
,
1049 static void nfs_pageio_init_write_mds(struct nfs_pageio_descriptor
*pgio
,
1050 struct inode
*inode
, int ioflags
)
1052 nfs_pageio_init(pgio
, inode
, &nfs_pageio_write_ops
,
1053 NFS_SERVER(inode
)->wsize
, ioflags
);
1056 static void nfs_pageio_init_write(struct nfs_pageio_descriptor
*pgio
,
1057 struct inode
*inode
, int ioflags
)
1059 if (!pnfs_pageio_init_write(pgio
, inode
, ioflags
))
1060 nfs_pageio_init_write_mds(pgio
, inode
, ioflags
);
1064 * Handle a write reply that flushed part of a page.
1066 static void nfs_writeback_done_partial(struct rpc_task
*task
, void *calldata
)
1068 struct nfs_write_data
*data
= calldata
;
1070 dprintk("NFS: %5u write(%s/%lld %d@%lld)",
1072 data
->req
->wb_context
->path
.dentry
->d_inode
->i_sb
->s_id
,
1074 NFS_FILEID(data
->req
->wb_context
->path
.dentry
->d_inode
),
1075 data
->req
->wb_bytes
, (long long)req_offset(data
->req
));
1077 nfs_writeback_done(task
, data
);
1080 static void nfs_writeback_release_partial(void *calldata
)
1082 struct nfs_write_data
*data
= calldata
;
1083 struct nfs_page
*req
= data
->req
;
1084 struct page
*page
= req
->wb_page
;
1085 int status
= data
->task
.tk_status
;
1088 nfs_set_pageerror(page
);
1089 nfs_context_set_write_error(req
->wb_context
, status
);
1090 dprintk(", error = %d\n", status
);
1094 if (nfs_write_need_commit(data
)) {
1095 struct inode
*inode
= page
->mapping
->host
;
1097 spin_lock(&inode
->i_lock
);
1098 if (test_bit(PG_NEED_RESCHED
, &req
->wb_flags
)) {
1099 /* Do nothing we need to resend the writes */
1100 } else if (!test_and_set_bit(PG_NEED_COMMIT
, &req
->wb_flags
)) {
1101 memcpy(&req
->wb_verf
, &data
->verf
, sizeof(req
->wb_verf
));
1102 dprintk(" defer commit\n");
1103 } else if (memcmp(&req
->wb_verf
, &data
->verf
, sizeof(req
->wb_verf
))) {
1104 set_bit(PG_NEED_RESCHED
, &req
->wb_flags
);
1105 clear_bit(PG_NEED_COMMIT
, &req
->wb_flags
);
1106 dprintk(" server reboot detected\n");
1108 spin_unlock(&inode
->i_lock
);
1113 if (atomic_dec_and_test(&req
->wb_complete
))
1114 nfs_writepage_release(req
, data
);
1115 nfs_writedata_release(calldata
);
1118 #if defined(CONFIG_NFS_V4_1)
1119 void nfs_write_prepare(struct rpc_task
*task
, void *calldata
)
1121 struct nfs_write_data
*data
= calldata
;
1123 if (nfs4_setup_sequence(NFS_SERVER(data
->inode
),
1124 &data
->args
.seq_args
,
1125 &data
->res
.seq_res
, 1, task
))
1127 rpc_call_start(task
);
1129 #endif /* CONFIG_NFS_V4_1 */
1131 static const struct rpc_call_ops nfs_write_partial_ops
= {
1132 #if defined(CONFIG_NFS_V4_1)
1133 .rpc_call_prepare
= nfs_write_prepare
,
1134 #endif /* CONFIG_NFS_V4_1 */
1135 .rpc_call_done
= nfs_writeback_done_partial
,
1136 .rpc_release
= nfs_writeback_release_partial
,
1140 * Handle a write reply that flushes a whole page.
1142 * FIXME: There is an inherent race with invalidate_inode_pages and
1143 * writebacks since the page->count is kept > 1 for as long
1144 * as the page has a write request pending.
1146 static void nfs_writeback_done_full(struct rpc_task
*task
, void *calldata
)
1148 struct nfs_write_data
*data
= calldata
;
1150 nfs_writeback_done(task
, data
);
1153 static void nfs_writeback_release_full(void *calldata
)
1155 struct nfs_write_data
*data
= calldata
;
1156 int status
= data
->task
.tk_status
;
1158 /* Update attributes as result of writeback. */
1159 while (!list_empty(&data
->pages
)) {
1160 struct nfs_page
*req
= nfs_list_entry(data
->pages
.next
);
1161 struct page
*page
= req
->wb_page
;
1163 nfs_list_remove_request(req
);
1165 dprintk("NFS: %5u write (%s/%lld %d@%lld)",
1167 req
->wb_context
->path
.dentry
->d_inode
->i_sb
->s_id
,
1168 (long long)NFS_FILEID(req
->wb_context
->path
.dentry
->d_inode
),
1170 (long long)req_offset(req
));
1173 nfs_set_pageerror(page
);
1174 nfs_context_set_write_error(req
->wb_context
, status
);
1175 dprintk(", error = %d\n", status
);
1176 goto remove_request
;
1179 if (nfs_write_need_commit(data
)) {
1180 memcpy(&req
->wb_verf
, &data
->verf
, sizeof(req
->wb_verf
));
1181 nfs_mark_request_commit(req
, data
->lseg
);
1182 dprintk(" marked for commit\n");
1187 nfs_inode_remove_request(req
);
1189 nfs_clear_page_tag_locked(req
);
1190 nfs_end_page_writeback(page
);
1192 nfs_writedata_release(calldata
);
1195 static const struct rpc_call_ops nfs_write_full_ops
= {
1196 #if defined(CONFIG_NFS_V4_1)
1197 .rpc_call_prepare
= nfs_write_prepare
,
1198 #endif /* CONFIG_NFS_V4_1 */
1199 .rpc_call_done
= nfs_writeback_done_full
,
1200 .rpc_release
= nfs_writeback_release_full
,
1205 * This function is called when the WRITE call is complete.
1207 void nfs_writeback_done(struct rpc_task
*task
, struct nfs_write_data
*data
)
1209 struct nfs_writeargs
*argp
= &data
->args
;
1210 struct nfs_writeres
*resp
= &data
->res
;
1211 struct nfs_server
*server
= NFS_SERVER(data
->inode
);
1214 dprintk("NFS: %5u nfs_writeback_done (status %d)\n",
1215 task
->tk_pid
, task
->tk_status
);
1218 * ->write_done will attempt to use post-op attributes to detect
1219 * conflicting writes by other clients. A strict interpretation
1220 * of close-to-open would allow us to continue caching even if
1221 * another writer had changed the file, but some applications
1222 * depend on tighter cache coherency when writing.
1224 status
= NFS_PROTO(data
->inode
)->write_done(task
, data
);
1227 nfs_add_stats(data
->inode
, NFSIOS_SERVERWRITTENBYTES
, resp
->count
);
1229 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
1230 if (resp
->verf
->committed
< argp
->stable
&& task
->tk_status
>= 0) {
1231 /* We tried a write call, but the server did not
1232 * commit data to stable storage even though we
1234 * Note: There is a known bug in Tru64 < 5.0 in which
1235 * the server reports NFS_DATA_SYNC, but performs
1236 * NFS_FILE_SYNC. We therefore implement this checking
1237 * as a dprintk() in order to avoid filling syslog.
1239 static unsigned long complain
;
1241 /* Note this will print the MDS for a DS write */
1242 if (time_before(complain
, jiffies
)) {
1243 dprintk("NFS: faulty NFS server %s:"
1244 " (committed = %d) != (stable = %d)\n",
1245 server
->nfs_client
->cl_hostname
,
1246 resp
->verf
->committed
, argp
->stable
);
1247 complain
= jiffies
+ 300 * HZ
;
1251 /* Is this a short write? */
1252 if (task
->tk_status
>= 0 && resp
->count
< argp
->count
) {
1253 static unsigned long complain
;
1255 nfs_inc_stats(data
->inode
, NFSIOS_SHORTWRITE
);
1257 /* Has the server at least made some progress? */
1258 if (resp
->count
!= 0) {
1259 /* Was this an NFSv2 write or an NFSv3 stable write? */
1260 if (resp
->verf
->committed
!= NFS_UNSTABLE
) {
1261 /* Resend from where the server left off */
1262 data
->mds_offset
+= resp
->count
;
1263 argp
->offset
+= resp
->count
;
1264 argp
->pgbase
+= resp
->count
;
1265 argp
->count
-= resp
->count
;
1267 /* Resend as a stable write in order to avoid
1268 * headaches in the case of a server crash.
1270 argp
->stable
= NFS_FILE_SYNC
;
1272 nfs_restart_rpc(task
, server
->nfs_client
);
1275 if (time_before(complain
, jiffies
)) {
1277 "NFS: Server wrote zero bytes, expected %u.\n",
1279 complain
= jiffies
+ 300 * HZ
;
1281 /* Can't do anything about it except throw an error. */
1282 task
->tk_status
= -EIO
;
1288 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
1289 static int nfs_commit_set_lock(struct nfs_inode
*nfsi
, int may_wait
)
1293 if (!test_and_set_bit(NFS_INO_COMMIT
, &nfsi
->flags
))
1297 ret
= out_of_line_wait_on_bit_lock(&nfsi
->flags
,
1299 nfs_wait_bit_killable
,
1301 return (ret
< 0) ? ret
: 1;
1304 void nfs_commit_clear_lock(struct nfs_inode
*nfsi
)
1306 clear_bit(NFS_INO_COMMIT
, &nfsi
->flags
);
1307 smp_mb__after_clear_bit();
1308 wake_up_bit(&nfsi
->flags
, NFS_INO_COMMIT
);
1310 EXPORT_SYMBOL_GPL(nfs_commit_clear_lock
);
1312 void nfs_commitdata_release(void *data
)
1314 struct nfs_write_data
*wdata
= data
;
1316 put_lseg(wdata
->lseg
);
1317 put_nfs_open_context(wdata
->args
.context
);
1318 nfs_commit_free(wdata
);
1320 EXPORT_SYMBOL_GPL(nfs_commitdata_release
);
1322 int nfs_initiate_commit(struct nfs_write_data
*data
, struct rpc_clnt
*clnt
,
1323 const struct rpc_call_ops
*call_ops
,
1326 struct rpc_task
*task
;
1327 int priority
= flush_task_priority(how
);
1328 struct rpc_message msg
= {
1329 .rpc_argp
= &data
->args
,
1330 .rpc_resp
= &data
->res
,
1331 .rpc_cred
= data
->cred
,
1333 struct rpc_task_setup task_setup_data
= {
1334 .task
= &data
->task
,
1336 .rpc_message
= &msg
,
1337 .callback_ops
= call_ops
,
1338 .callback_data
= data
,
1339 .workqueue
= nfsiod_workqueue
,
1340 .flags
= RPC_TASK_ASYNC
,
1341 .priority
= priority
,
1343 /* Set up the initial task struct. */
1344 NFS_PROTO(data
->inode
)->commit_setup(data
, &msg
);
1346 dprintk("NFS: %5u initiated commit call\n", data
->task
.tk_pid
);
1348 task
= rpc_run_task(&task_setup_data
);
1350 return PTR_ERR(task
);
1351 if (how
& FLUSH_SYNC
)
1352 rpc_wait_for_completion_task(task
);
1356 EXPORT_SYMBOL_GPL(nfs_initiate_commit
);
1359 * Set up the argument/result storage required for the RPC call.
1361 void nfs_init_commit(struct nfs_write_data
*data
,
1362 struct list_head
*head
,
1363 struct pnfs_layout_segment
*lseg
)
1365 struct nfs_page
*first
= nfs_list_entry(head
->next
);
1366 struct inode
*inode
= first
->wb_context
->path
.dentry
->d_inode
;
1368 /* Set up the RPC argument and reply structs
1369 * NB: take care not to mess about with data->commit et al. */
1371 list_splice_init(head
, &data
->pages
);
1373 data
->inode
= inode
;
1374 data
->cred
= first
->wb_context
->cred
;
1375 data
->lseg
= lseg
; /* reference transferred */
1376 data
->mds_ops
= &nfs_commit_ops
;
1378 data
->args
.fh
= NFS_FH(data
->inode
);
1379 /* Note: we always request a commit of the entire inode */
1380 data
->args
.offset
= 0;
1381 data
->args
.count
= 0;
1382 data
->args
.context
= get_nfs_open_context(first
->wb_context
);
1383 data
->res
.count
= 0;
1384 data
->res
.fattr
= &data
->fattr
;
1385 data
->res
.verf
= &data
->verf
;
1386 nfs_fattr_init(&data
->fattr
);
1388 EXPORT_SYMBOL_GPL(nfs_init_commit
);
1390 void nfs_retry_commit(struct list_head
*page_list
,
1391 struct pnfs_layout_segment
*lseg
)
1393 struct nfs_page
*req
;
1395 while (!list_empty(page_list
)) {
1396 req
= nfs_list_entry(page_list
->next
);
1397 nfs_list_remove_request(req
);
1398 nfs_mark_request_commit(req
, lseg
);
1399 dec_zone_page_state(req
->wb_page
, NR_UNSTABLE_NFS
);
1400 dec_bdi_stat(req
->wb_page
->mapping
->backing_dev_info
,
1402 nfs_clear_page_tag_locked(req
);
1405 EXPORT_SYMBOL_GPL(nfs_retry_commit
);
1408 * Commit dirty pages
1411 nfs_commit_list(struct inode
*inode
, struct list_head
*head
, int how
)
1413 struct nfs_write_data
*data
;
1415 data
= nfs_commitdata_alloc();
1420 /* Set up the argument struct */
1421 nfs_init_commit(data
, head
, NULL
);
1422 return nfs_initiate_commit(data
, NFS_CLIENT(inode
), data
->mds_ops
, how
);
1424 nfs_retry_commit(head
, NULL
);
1425 nfs_commit_clear_lock(NFS_I(inode
));
1430 * COMMIT call returned
1432 static void nfs_commit_done(struct rpc_task
*task
, void *calldata
)
1434 struct nfs_write_data
*data
= calldata
;
1436 dprintk("NFS: %5u nfs_commit_done (status %d)\n",
1437 task
->tk_pid
, task
->tk_status
);
1439 /* Call the NFS version-specific code */
1440 NFS_PROTO(data
->inode
)->commit_done(task
, data
);
1443 void nfs_commit_release_pages(struct nfs_write_data
*data
)
1445 struct nfs_page
*req
;
1446 int status
= data
->task
.tk_status
;
1448 while (!list_empty(&data
->pages
)) {
1449 req
= nfs_list_entry(data
->pages
.next
);
1450 nfs_list_remove_request(req
);
1451 nfs_clear_request_commit(req
);
1453 dprintk("NFS: commit (%s/%lld %d@%lld)",
1454 req
->wb_context
->path
.dentry
->d_inode
->i_sb
->s_id
,
1455 (long long)NFS_FILEID(req
->wb_context
->path
.dentry
->d_inode
),
1457 (long long)req_offset(req
));
1459 nfs_context_set_write_error(req
->wb_context
, status
);
1460 nfs_inode_remove_request(req
);
1461 dprintk(", error = %d\n", status
);
1465 /* Okay, COMMIT succeeded, apparently. Check the verifier
1466 * returned by the server against all stored verfs. */
1467 if (!memcmp(req
->wb_verf
.verifier
, data
->verf
.verifier
, sizeof(data
->verf
.verifier
))) {
1468 /* We have a match */
1469 nfs_inode_remove_request(req
);
1473 /* We have a mismatch. Write the page again */
1474 dprintk(" mismatch\n");
1475 nfs_mark_request_dirty(req
);
1477 nfs_clear_page_tag_locked(req
);
1480 EXPORT_SYMBOL_GPL(nfs_commit_release_pages
);
1482 static void nfs_commit_release(void *calldata
)
1484 struct nfs_write_data
*data
= calldata
;
1486 nfs_commit_release_pages(data
);
1487 nfs_commit_clear_lock(NFS_I(data
->inode
));
1488 nfs_commitdata_release(calldata
);
1491 static const struct rpc_call_ops nfs_commit_ops
= {
1492 #if defined(CONFIG_NFS_V4_1)
1493 .rpc_call_prepare
= nfs_write_prepare
,
1494 #endif /* CONFIG_NFS_V4_1 */
1495 .rpc_call_done
= nfs_commit_done
,
1496 .rpc_release
= nfs_commit_release
,
1499 int nfs_commit_inode(struct inode
*inode
, int how
)
1502 int may_wait
= how
& FLUSH_SYNC
;
1505 res
= nfs_commit_set_lock(NFS_I(inode
), may_wait
);
1507 goto out_mark_dirty
;
1508 res
= nfs_scan_commit(inode
, &head
, 0, 0);
1512 error
= pnfs_commit_list(inode
, &head
, how
);
1513 if (error
== PNFS_NOT_ATTEMPTED
)
1514 error
= nfs_commit_list(inode
, &head
, how
);
1518 goto out_mark_dirty
;
1519 error
= wait_on_bit(&NFS_I(inode
)->flags
,
1521 nfs_wait_bit_killable
,
1526 nfs_commit_clear_lock(NFS_I(inode
));
1528 /* Note: If we exit without ensuring that the commit is complete,
1529 * we must mark the inode as dirty. Otherwise, future calls to
1530 * sync_inode() with the WB_SYNC_ALL flag set will fail to ensure
1531 * that the data is on the disk.
1534 __mark_inode_dirty(inode
, I_DIRTY_DATASYNC
);
1538 static int nfs_commit_unstable_pages(struct inode
*inode
, struct writeback_control
*wbc
)
1540 struct nfs_inode
*nfsi
= NFS_I(inode
);
1541 int flags
= FLUSH_SYNC
;
1544 if (wbc
->sync_mode
== WB_SYNC_NONE
) {
1545 /* Don't commit yet if this is a non-blocking flush and there
1546 * are a lot of outstanding writes for this mapping.
1548 if (nfsi
->ncommit
<= (nfsi
->npages
>> 1))
1549 goto out_mark_dirty
;
1551 /* don't wait for the COMMIT response */
1555 ret
= nfs_commit_inode(inode
, flags
);
1557 if (wbc
->sync_mode
== WB_SYNC_NONE
) {
1558 if (ret
< wbc
->nr_to_write
)
1559 wbc
->nr_to_write
-= ret
;
1561 wbc
->nr_to_write
= 0;
1566 __mark_inode_dirty(inode
, I_DIRTY_DATASYNC
);
1570 static int nfs_commit_unstable_pages(struct inode
*inode
, struct writeback_control
*wbc
)
1576 int nfs_write_inode(struct inode
*inode
, struct writeback_control
*wbc
)
1580 ret
= nfs_commit_unstable_pages(inode
, wbc
);
1581 if (ret
>= 0 && test_bit(NFS_INO_LAYOUTCOMMIT
, &NFS_I(inode
)->flags
)) {
1585 if (wbc
->sync_mode
== WB_SYNC_NONE
|| wbc
->nonblocking
||
1586 wbc
->for_background
)
1589 status
= pnfs_layoutcommit_inode(inode
, sync
);
1597 * flush the inode to disk.
1599 int nfs_wb_all(struct inode
*inode
)
1601 struct writeback_control wbc
= {
1602 .sync_mode
= WB_SYNC_ALL
,
1603 .nr_to_write
= LONG_MAX
,
1605 .range_end
= LLONG_MAX
,
1608 return sync_inode(inode
, &wbc
);
1611 int nfs_wb_page_cancel(struct inode
*inode
, struct page
*page
)
1613 struct nfs_page
*req
;
1616 BUG_ON(!PageLocked(page
));
1618 wait_on_page_writeback(page
);
1619 req
= nfs_page_find_request(page
);
1622 if (nfs_lock_request_dontget(req
)) {
1623 nfs_inode_remove_request(req
);
1625 * In case nfs_inode_remove_request has marked the
1626 * page as being dirty
1628 cancel_dirty_page(page
, PAGE_CACHE_SIZE
);
1629 nfs_unlock_request(req
);
1632 ret
= nfs_wait_on_request(req
);
1633 nfs_release_request(req
);
1641 * Write back all requests on one page - we do this before reading it.
1643 int nfs_wb_page(struct inode
*inode
, struct page
*page
)
1645 loff_t range_start
= page_offset(page
);
1646 loff_t range_end
= range_start
+ (loff_t
)(PAGE_CACHE_SIZE
- 1);
1647 struct writeback_control wbc
= {
1648 .sync_mode
= WB_SYNC_ALL
,
1650 .range_start
= range_start
,
1651 .range_end
= range_end
,
1656 wait_on_page_writeback(page
);
1657 if (clear_page_dirty_for_io(page
)) {
1658 ret
= nfs_writepage_locked(page
, &wbc
);
1663 if (!PagePrivate(page
))
1665 ret
= nfs_commit_inode(inode
, FLUSH_SYNC
);
1674 #ifdef CONFIG_MIGRATION
1675 int nfs_migrate_page(struct address_space
*mapping
, struct page
*newpage
,
1678 struct nfs_page
*req
;
1681 nfs_fscache_release_page(page
, GFP_KERNEL
);
1683 req
= nfs_find_and_lock_request(page
, false);
1688 ret
= migrate_page(mapping
, newpage
, page
);
1693 page_cache_get(newpage
);
1694 spin_lock(&mapping
->host
->i_lock
);
1695 req
->wb_page
= newpage
;
1696 SetPagePrivate(newpage
);
1697 set_page_private(newpage
, (unsigned long)req
);
1698 ClearPagePrivate(page
);
1699 set_page_private(page
, 0);
1700 spin_unlock(&mapping
->host
->i_lock
);
1701 page_cache_release(page
);
1703 nfs_clear_page_tag_locked(req
);
1709 int __init
nfs_init_writepagecache(void)
1711 nfs_wdata_cachep
= kmem_cache_create("nfs_write_data",
1712 sizeof(struct nfs_write_data
),
1713 0, SLAB_HWCACHE_ALIGN
,
1715 if (nfs_wdata_cachep
== NULL
)
1718 nfs_wdata_mempool
= mempool_create_slab_pool(MIN_POOL_WRITE
,
1720 if (nfs_wdata_mempool
== NULL
)
1723 nfs_commit_mempool
= mempool_create_slab_pool(MIN_POOL_COMMIT
,
1725 if (nfs_commit_mempool
== NULL
)
1729 * NFS congestion size, scale with available memory.
1741 * This allows larger machines to have larger/more transfers.
1742 * Limit the default to 256M
1744 nfs_congestion_kb
= (16*int_sqrt(totalram_pages
)) << (PAGE_SHIFT
-10);
1745 if (nfs_congestion_kb
> 256*1024)
1746 nfs_congestion_kb
= 256*1024;
1751 void nfs_destroy_writepagecache(void)
1753 mempool_destroy(nfs_commit_mempool
);
1754 mempool_destroy(nfs_wdata_mempool
);
1755 kmem_cache_destroy(nfs_wdata_cachep
);