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>
23 #include <linux/export.h>
25 #include <asm/uaccess.h>
27 #include "delegation.h"
34 #define NFSDBG_FACILITY NFSDBG_PAGECACHE
36 #define MIN_POOL_WRITE (32)
37 #define MIN_POOL_COMMIT (4)
40 * Local function declarations
42 static void nfs_pageio_init_write(struct nfs_pageio_descriptor
*desc
,
43 struct inode
*inode
, int ioflags
);
44 static void nfs_redirty_request(struct nfs_page
*req
);
45 static const struct rpc_call_ops nfs_write_partial_ops
;
46 static const struct rpc_call_ops nfs_write_full_ops
;
47 static const struct rpc_call_ops nfs_commit_ops
;
49 static struct kmem_cache
*nfs_wdata_cachep
;
50 static mempool_t
*nfs_wdata_mempool
;
51 static mempool_t
*nfs_commit_mempool
;
53 struct nfs_write_data
*nfs_commitdata_alloc(void)
55 struct nfs_write_data
*p
= mempool_alloc(nfs_commit_mempool
, GFP_NOFS
);
58 memset(p
, 0, sizeof(*p
));
59 INIT_LIST_HEAD(&p
->pages
);
63 EXPORT_SYMBOL_GPL(nfs_commitdata_alloc
);
65 void nfs_commit_free(struct nfs_write_data
*p
)
67 if (p
&& (p
->pagevec
!= &p
->page_array
[0]))
69 mempool_free(p
, nfs_commit_mempool
);
71 EXPORT_SYMBOL_GPL(nfs_commit_free
);
73 struct nfs_write_data
*nfs_writedata_alloc(unsigned int pagecount
)
75 struct nfs_write_data
*p
= mempool_alloc(nfs_wdata_mempool
, GFP_NOFS
);
78 memset(p
, 0, sizeof(*p
));
79 INIT_LIST_HEAD(&p
->pages
);
80 p
->npages
= pagecount
;
81 if (pagecount
<= ARRAY_SIZE(p
->page_array
))
82 p
->pagevec
= p
->page_array
;
84 p
->pagevec
= kcalloc(pagecount
, sizeof(struct page
*), GFP_NOFS
);
86 mempool_free(p
, nfs_wdata_mempool
);
94 void nfs_writedata_free(struct nfs_write_data
*p
)
96 if (p
&& (p
->pagevec
!= &p
->page_array
[0]))
98 mempool_free(p
, nfs_wdata_mempool
);
101 void nfs_writedata_release(struct nfs_write_data
*wdata
)
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_lock_request_dontget(req
))
240 /* Note: If we hold the page lock, as is the case in nfs_writepage,
241 * then the call to nfs_lock_request_dontget() 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 void nfs_inode_add_request(struct inode
*inode
, struct nfs_page
*req
)
379 struct nfs_inode
*nfsi
= NFS_I(inode
);
381 /* Lock the request! */
382 nfs_lock_request_dontget(req
);
384 spin_lock(&inode
->i_lock
);
385 if (!nfsi
->npages
&& nfs_have_delegation(inode
, FMODE_WRITE
))
387 set_bit(PG_MAPPED
, &req
->wb_flags
);
388 SetPagePrivate(req
->wb_page
);
389 set_page_private(req
->wb_page
, (unsigned long)req
);
391 kref_get(&req
->wb_kref
);
392 spin_unlock(&inode
->i_lock
);
396 * Remove a write request from an inode
398 static void nfs_inode_remove_request(struct nfs_page
*req
)
400 struct inode
*inode
= req
->wb_context
->dentry
->d_inode
;
401 struct nfs_inode
*nfsi
= NFS_I(inode
);
403 BUG_ON (!NFS_WBACK_BUSY(req
));
405 spin_lock(&inode
->i_lock
);
406 set_page_private(req
->wb_page
, 0);
407 ClearPagePrivate(req
->wb_page
);
408 clear_bit(PG_MAPPED
, &req
->wb_flags
);
410 spin_unlock(&inode
->i_lock
);
411 nfs_release_request(req
);
415 nfs_mark_request_dirty(struct nfs_page
*req
)
417 __set_page_dirty_nobuffers(req
->wb_page
);
420 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
422 * nfs_request_add_commit_list - add request to a commit list
423 * @req: pointer to a struct nfs_page
424 * @head: commit list head
426 * This sets the PG_CLEAN bit, updates the inode global count of
427 * number of outstanding requests requiring a commit as well as
430 * The caller must _not_ hold the inode->i_lock, but must be
431 * holding the nfs_page lock.
434 nfs_request_add_commit_list(struct nfs_page
*req
, struct list_head
*head
)
436 struct inode
*inode
= req
->wb_context
->dentry
->d_inode
;
438 set_bit(PG_CLEAN
, &(req
)->wb_flags
);
439 spin_lock(&inode
->i_lock
);
440 nfs_list_add_request(req
, head
);
441 NFS_I(inode
)->ncommit
++;
442 spin_unlock(&inode
->i_lock
);
443 inc_zone_page_state(req
->wb_page
, NR_UNSTABLE_NFS
);
444 inc_bdi_stat(req
->wb_page
->mapping
->backing_dev_info
, BDI_RECLAIMABLE
);
445 __mark_inode_dirty(inode
, I_DIRTY_DATASYNC
);
447 EXPORT_SYMBOL_GPL(nfs_request_add_commit_list
);
450 * nfs_request_remove_commit_list - Remove request from a commit list
451 * @req: pointer to a nfs_page
453 * This clears the PG_CLEAN bit, and updates the inode global count of
454 * number of outstanding requests requiring a commit
455 * It does not update the MM page stats.
457 * The caller _must_ hold the inode->i_lock and the nfs_page lock.
460 nfs_request_remove_commit_list(struct nfs_page
*req
)
462 struct inode
*inode
= req
->wb_context
->dentry
->d_inode
;
464 if (!test_and_clear_bit(PG_CLEAN
, &(req
)->wb_flags
))
466 nfs_list_remove_request(req
);
467 NFS_I(inode
)->ncommit
--;
469 EXPORT_SYMBOL_GPL(nfs_request_remove_commit_list
);
473 * Add a request to the inode's commit list.
476 nfs_mark_request_commit(struct nfs_page
*req
, struct pnfs_layout_segment
*lseg
)
478 struct inode
*inode
= req
->wb_context
->dentry
->d_inode
;
480 if (pnfs_mark_request_commit(req
, lseg
))
482 nfs_request_add_commit_list(req
, &NFS_I(inode
)->commit_list
);
486 nfs_clear_page_commit(struct page
*page
)
488 dec_zone_page_state(page
, NR_UNSTABLE_NFS
);
489 dec_bdi_stat(page
->mapping
->backing_dev_info
, BDI_RECLAIMABLE
);
493 nfs_clear_request_commit(struct nfs_page
*req
)
495 if (test_bit(PG_CLEAN
, &req
->wb_flags
)) {
496 struct inode
*inode
= req
->wb_context
->dentry
->d_inode
;
498 if (!pnfs_clear_request_commit(req
)) {
499 spin_lock(&inode
->i_lock
);
500 nfs_request_remove_commit_list(req
);
501 spin_unlock(&inode
->i_lock
);
503 nfs_clear_page_commit(req
->wb_page
);
508 int nfs_write_need_commit(struct nfs_write_data
*data
)
510 if (data
->verf
.committed
== NFS_DATA_SYNC
)
511 return data
->lseg
== NULL
;
513 return data
->verf
.committed
!= NFS_FILE_SYNC
;
517 int nfs_reschedule_unstable_write(struct nfs_page
*req
,
518 struct nfs_write_data
*data
)
520 if (test_and_clear_bit(PG_NEED_COMMIT
, &req
->wb_flags
)) {
521 nfs_mark_request_commit(req
, data
->lseg
);
524 if (test_and_clear_bit(PG_NEED_RESCHED
, &req
->wb_flags
)) {
525 nfs_mark_request_dirty(req
);
532 nfs_mark_request_commit(struct nfs_page
*req
, struct pnfs_layout_segment
*lseg
)
537 nfs_clear_request_commit(struct nfs_page
*req
)
542 int nfs_write_need_commit(struct nfs_write_data
*data
)
548 int nfs_reschedule_unstable_write(struct nfs_page
*req
,
549 struct nfs_write_data
*data
)
555 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
557 nfs_need_commit(struct nfs_inode
*nfsi
)
559 return nfsi
->ncommit
> 0;
562 /* i_lock held by caller */
564 nfs_scan_commit_list(struct list_head
*src
, struct list_head
*dst
, int max
,
567 struct nfs_page
*req
, *tmp
;
570 list_for_each_entry_safe(req
, tmp
, src
, wb_list
) {
571 if (!nfs_lock_request(req
))
573 if (cond_resched_lock(lock
))
574 list_safe_reset_next(req
, tmp
, wb_list
);
575 nfs_request_remove_commit_list(req
);
576 nfs_list_add_request(req
, dst
);
585 * nfs_scan_commit - Scan an inode for commit requests
586 * @inode: NFS inode to scan
587 * @dst: destination list
589 * Moves requests from the inode's 'commit' request list.
590 * The requests are *not* checked to ensure that they form a contiguous set.
593 nfs_scan_commit(struct inode
*inode
, struct list_head
*dst
)
595 struct nfs_inode
*nfsi
= NFS_I(inode
);
598 spin_lock(&inode
->i_lock
);
599 if (nfsi
->ncommit
> 0) {
600 const int max
= INT_MAX
;
602 ret
= nfs_scan_commit_list(&nfsi
->commit_list
, dst
, max
,
604 ret
+= pnfs_scan_commit_lists(inode
, max
- ret
,
607 spin_unlock(&inode
->i_lock
);
612 static inline int nfs_need_commit(struct nfs_inode
*nfsi
)
617 static inline int nfs_scan_commit(struct inode
*inode
, struct list_head
*dst
)
624 * Search for an existing write request, and attempt to update
625 * it to reflect a new dirty region on a given page.
627 * If the attempt fails, then the existing request is flushed out
630 static struct nfs_page
*nfs_try_to_update_request(struct inode
*inode
,
635 struct nfs_page
*req
;
640 if (!PagePrivate(page
))
643 end
= offset
+ bytes
;
644 spin_lock(&inode
->i_lock
);
647 req
= nfs_page_find_request_locked(page
);
651 rqend
= req
->wb_offset
+ req
->wb_bytes
;
653 * Tell the caller to flush out the request if
654 * the offsets are non-contiguous.
655 * Note: nfs_flush_incompatible() will already
656 * have flushed out requests having wrong owners.
659 || end
< req
->wb_offset
)
662 if (nfs_lock_request_dontget(req
))
665 /* The request is locked, so wait and then retry */
666 spin_unlock(&inode
->i_lock
);
667 error
= nfs_wait_on_request(req
);
668 nfs_release_request(req
);
671 spin_lock(&inode
->i_lock
);
674 /* Okay, the request matches. Update the region */
675 if (offset
< req
->wb_offset
) {
676 req
->wb_offset
= offset
;
677 req
->wb_pgbase
= offset
;
680 req
->wb_bytes
= end
- req
->wb_offset
;
682 req
->wb_bytes
= rqend
- req
->wb_offset
;
684 spin_unlock(&inode
->i_lock
);
685 nfs_clear_request_commit(req
);
688 spin_unlock(&inode
->i_lock
);
689 nfs_release_request(req
);
690 error
= nfs_wb_page(inode
, page
);
692 return ERR_PTR(error
);
696 * Try to update an existing write request, or create one if there is none.
698 * Note: Should always be called with the Page Lock held to prevent races
699 * if we have to add a new request. Also assumes that the caller has
700 * already called nfs_flush_incompatible() if necessary.
702 static struct nfs_page
* nfs_setup_write_request(struct nfs_open_context
* ctx
,
703 struct page
*page
, unsigned int offset
, unsigned int bytes
)
705 struct inode
*inode
= page
->mapping
->host
;
706 struct nfs_page
*req
;
708 req
= nfs_try_to_update_request(inode
, page
, offset
, bytes
);
711 req
= nfs_create_request(ctx
, inode
, page
, offset
, bytes
);
714 nfs_inode_add_request(inode
, req
);
719 static int nfs_writepage_setup(struct nfs_open_context
*ctx
, struct page
*page
,
720 unsigned int offset
, unsigned int count
)
722 struct nfs_page
*req
;
724 req
= nfs_setup_write_request(ctx
, page
, offset
, count
);
727 /* Update file length */
728 nfs_grow_file(page
, offset
, count
);
729 nfs_mark_uptodate(page
, req
->wb_pgbase
, req
->wb_bytes
);
730 nfs_mark_request_dirty(req
);
731 nfs_unlock_request(req
);
735 int nfs_flush_incompatible(struct file
*file
, struct page
*page
)
737 struct nfs_open_context
*ctx
= nfs_file_open_context(file
);
738 struct nfs_page
*req
;
739 int do_flush
, status
;
741 * Look for a request corresponding to this page. If there
742 * is one, and it belongs to another file, we flush it out
743 * before we try to copy anything into the page. Do this
744 * due to the lack of an ACCESS-type call in NFSv2.
745 * Also do the same if we find a request from an existing
749 req
= nfs_page_find_request(page
);
752 do_flush
= req
->wb_page
!= page
|| req
->wb_context
!= ctx
||
753 req
->wb_lock_context
->lockowner
!= current
->files
||
754 req
->wb_lock_context
->pid
!= current
->tgid
;
755 nfs_release_request(req
);
758 status
= nfs_wb_page(page
->mapping
->host
, page
);
759 } while (status
== 0);
764 * If the page cache is marked as unsafe or invalid, then we can't rely on
765 * the PageUptodate() flag. In this case, we will need to turn off
766 * write optimisations that depend on the page contents being correct.
768 static int nfs_write_pageuptodate(struct page
*page
, struct inode
*inode
)
770 return PageUptodate(page
) &&
771 !(NFS_I(inode
)->cache_validity
& (NFS_INO_REVAL_PAGECACHE
|NFS_INO_INVALID_DATA
));
775 * Update and possibly write a cached page of an NFS file.
777 * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad
778 * things with a page scheduled for an RPC call (e.g. invalidate it).
780 int nfs_updatepage(struct file
*file
, struct page
*page
,
781 unsigned int offset
, unsigned int count
)
783 struct nfs_open_context
*ctx
= nfs_file_open_context(file
);
784 struct inode
*inode
= page
->mapping
->host
;
787 nfs_inc_stats(inode
, NFSIOS_VFSUPDATEPAGE
);
789 dprintk("NFS: nfs_updatepage(%s/%s %d@%lld)\n",
790 file
->f_path
.dentry
->d_parent
->d_name
.name
,
791 file
->f_path
.dentry
->d_name
.name
, count
,
792 (long long)(page_offset(page
) + offset
));
794 /* If we're not using byte range locks, and we know the page
795 * is up to date, it may be more efficient to extend the write
796 * to cover the entire page in order to avoid fragmentation
799 if (nfs_write_pageuptodate(page
, inode
) &&
800 inode
->i_flock
== NULL
&&
801 !(file
->f_flags
& O_DSYNC
)) {
802 count
= max(count
+ offset
, nfs_page_length(page
));
806 status
= nfs_writepage_setup(ctx
, page
, offset
, count
);
808 nfs_set_pageerror(page
);
810 __set_page_dirty_nobuffers(page
);
812 dprintk("NFS: nfs_updatepage returns %d (isize %lld)\n",
813 status
, (long long)i_size_read(inode
));
817 static void nfs_writepage_release(struct nfs_page
*req
,
818 struct nfs_write_data
*data
)
820 struct page
*page
= req
->wb_page
;
822 if (PageError(req
->wb_page
) || !nfs_reschedule_unstable_write(req
, data
))
823 nfs_inode_remove_request(req
);
824 nfs_unlock_request(req
);
825 nfs_end_page_writeback(page
);
828 static int flush_task_priority(int how
)
830 switch (how
& (FLUSH_HIGHPRI
|FLUSH_LOWPRI
)) {
832 return RPC_PRIORITY_HIGH
;
834 return RPC_PRIORITY_LOW
;
836 return RPC_PRIORITY_NORMAL
;
839 int nfs_initiate_write(struct nfs_write_data
*data
,
840 struct rpc_clnt
*clnt
,
841 const struct rpc_call_ops
*call_ops
,
844 struct inode
*inode
= data
->inode
;
845 int priority
= flush_task_priority(how
);
846 struct rpc_task
*task
;
847 struct rpc_message msg
= {
848 .rpc_argp
= &data
->args
,
849 .rpc_resp
= &data
->res
,
850 .rpc_cred
= data
->cred
,
852 struct rpc_task_setup task_setup_data
= {
856 .callback_ops
= call_ops
,
857 .callback_data
= data
,
858 .workqueue
= nfsiod_workqueue
,
859 .flags
= RPC_TASK_ASYNC
,
860 .priority
= priority
,
864 /* Set up the initial task struct. */
865 NFS_PROTO(inode
)->write_setup(data
, &msg
);
867 dprintk("NFS: %5u initiated write call "
868 "(req %s/%lld, %u bytes @ offset %llu)\n",
871 (long long)NFS_FILEID(inode
),
873 (unsigned long long)data
->args
.offset
);
875 task
= rpc_run_task(&task_setup_data
);
880 if (how
& FLUSH_SYNC
) {
881 ret
= rpc_wait_for_completion_task(task
);
883 ret
= task
->tk_status
;
889 EXPORT_SYMBOL_GPL(nfs_initiate_write
);
892 * Set up the argument/result storage required for the RPC call.
894 static void nfs_write_rpcsetup(struct nfs_page
*req
,
895 struct nfs_write_data
*data
,
896 unsigned int count
, unsigned int offset
,
899 struct inode
*inode
= req
->wb_context
->dentry
->d_inode
;
901 /* Set up the RPC argument and reply structs
902 * NB: take care not to mess about with data->commit et al. */
905 data
->inode
= inode
= req
->wb_context
->dentry
->d_inode
;
906 data
->cred
= req
->wb_context
->cred
;
908 data
->args
.fh
= NFS_FH(inode
);
909 data
->args
.offset
= req_offset(req
) + offset
;
910 /* pnfs_set_layoutcommit needs this */
911 data
->mds_offset
= data
->args
.offset
;
912 data
->args
.pgbase
= req
->wb_pgbase
+ offset
;
913 data
->args
.pages
= data
->pagevec
;
914 data
->args
.count
= count
;
915 data
->args
.context
= get_nfs_open_context(req
->wb_context
);
916 data
->args
.lock_context
= req
->wb_lock_context
;
917 data
->args
.stable
= NFS_UNSTABLE
;
918 switch (how
& (FLUSH_STABLE
| FLUSH_COND_STABLE
)) {
921 case FLUSH_COND_STABLE
:
922 if (nfs_need_commit(NFS_I(inode
)))
925 data
->args
.stable
= NFS_FILE_SYNC
;
928 data
->res
.fattr
= &data
->fattr
;
929 data
->res
.count
= count
;
930 data
->res
.verf
= &data
->verf
;
931 nfs_fattr_init(&data
->fattr
);
934 static int nfs_do_write(struct nfs_write_data
*data
,
935 const struct rpc_call_ops
*call_ops
,
938 struct inode
*inode
= data
->args
.context
->dentry
->d_inode
;
940 return nfs_initiate_write(data
, NFS_CLIENT(inode
), call_ops
, how
);
943 static int nfs_do_multiple_writes(struct list_head
*head
,
944 const struct rpc_call_ops
*call_ops
,
947 struct nfs_write_data
*data
;
950 while (!list_empty(head
)) {
953 data
= list_entry(head
->next
, struct nfs_write_data
, list
);
954 list_del_init(&data
->list
);
956 ret2
= nfs_do_write(data
, call_ops
, how
);
963 /* If a nfs_flush_* function fails, it should remove reqs from @head and
964 * call this on each, which will prepare them to be retried on next
965 * writeback using standard nfs.
967 static void nfs_redirty_request(struct nfs_page
*req
)
969 struct page
*page
= req
->wb_page
;
971 nfs_mark_request_dirty(req
);
972 nfs_unlock_request(req
);
973 nfs_end_page_writeback(page
);
977 * Generate multiple small requests to write out a single
978 * contiguous dirty area on one page.
980 static int nfs_flush_multi(struct nfs_pageio_descriptor
*desc
, struct list_head
*res
)
982 struct nfs_page
*req
= nfs_list_entry(desc
->pg_list
.next
);
983 struct page
*page
= req
->wb_page
;
984 struct nfs_write_data
*data
;
985 size_t wsize
= desc
->pg_bsize
, nbytes
;
990 nfs_list_remove_request(req
);
992 if ((desc
->pg_ioflags
& FLUSH_COND_STABLE
) &&
993 (desc
->pg_moreio
|| NFS_I(desc
->pg_inode
)->ncommit
||
994 desc
->pg_count
> wsize
))
995 desc
->pg_ioflags
&= ~FLUSH_COND_STABLE
;
999 nbytes
= desc
->pg_count
;
1001 size_t len
= min(nbytes
, wsize
);
1003 data
= nfs_writedata_alloc(1);
1006 data
->pagevec
[0] = page
;
1007 nfs_write_rpcsetup(req
, data
, len
, offset
, desc
->pg_ioflags
);
1008 list_add(&data
->list
, res
);
1012 } while (nbytes
!= 0);
1013 atomic_set(&req
->wb_complete
, requests
);
1014 desc
->pg_rpc_callops
= &nfs_write_partial_ops
;
1018 while (!list_empty(res
)) {
1019 data
= list_entry(res
->next
, struct nfs_write_data
, list
);
1020 list_del(&data
->list
);
1021 nfs_writedata_free(data
);
1023 nfs_redirty_request(req
);
1028 * Create an RPC task for the given write request and kick it.
1029 * The page must have been locked by the caller.
1031 * It may happen that the page we're passed is not marked dirty.
1032 * This is the case if nfs_updatepage detects a conflicting request
1033 * that has been written but not committed.
1035 static int nfs_flush_one(struct nfs_pageio_descriptor
*desc
, struct list_head
*res
)
1037 struct nfs_page
*req
;
1038 struct page
**pages
;
1039 struct nfs_write_data
*data
;
1040 struct list_head
*head
= &desc
->pg_list
;
1043 data
= nfs_writedata_alloc(nfs_page_array_len(desc
->pg_base
,
1046 while (!list_empty(head
)) {
1047 req
= nfs_list_entry(head
->next
);
1048 nfs_list_remove_request(req
);
1049 nfs_redirty_request(req
);
1054 pages
= data
->pagevec
;
1055 while (!list_empty(head
)) {
1056 req
= nfs_list_entry(head
->next
);
1057 nfs_list_remove_request(req
);
1058 nfs_list_add_request(req
, &data
->pages
);
1059 *pages
++ = req
->wb_page
;
1061 req
= nfs_list_entry(data
->pages
.next
);
1063 if ((desc
->pg_ioflags
& FLUSH_COND_STABLE
) &&
1064 (desc
->pg_moreio
|| NFS_I(desc
->pg_inode
)->ncommit
))
1065 desc
->pg_ioflags
&= ~FLUSH_COND_STABLE
;
1067 /* Set up the argument struct */
1068 nfs_write_rpcsetup(req
, data
, desc
->pg_count
, 0, desc
->pg_ioflags
);
1069 list_add(&data
->list
, res
);
1070 desc
->pg_rpc_callops
= &nfs_write_full_ops
;
1075 int nfs_generic_flush(struct nfs_pageio_descriptor
*desc
, struct list_head
*head
)
1077 if (desc
->pg_bsize
< PAGE_CACHE_SIZE
)
1078 return nfs_flush_multi(desc
, head
);
1079 return nfs_flush_one(desc
, head
);
1082 static int nfs_generic_pg_writepages(struct nfs_pageio_descriptor
*desc
)
1087 ret
= nfs_generic_flush(desc
, &head
);
1089 ret
= nfs_do_multiple_writes(&head
, desc
->pg_rpc_callops
,
1094 static const struct nfs_pageio_ops nfs_pageio_write_ops
= {
1095 .pg_test
= nfs_generic_pg_test
,
1096 .pg_doio
= nfs_generic_pg_writepages
,
1099 void nfs_pageio_init_write_mds(struct nfs_pageio_descriptor
*pgio
,
1100 struct inode
*inode
, int ioflags
)
1102 nfs_pageio_init(pgio
, inode
, &nfs_pageio_write_ops
,
1103 NFS_SERVER(inode
)->wsize
, ioflags
);
1106 void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor
*pgio
)
1108 pgio
->pg_ops
= &nfs_pageio_write_ops
;
1109 pgio
->pg_bsize
= NFS_SERVER(pgio
->pg_inode
)->wsize
;
1111 EXPORT_SYMBOL_GPL(nfs_pageio_reset_write_mds
);
1113 static void nfs_pageio_init_write(struct nfs_pageio_descriptor
*pgio
,
1114 struct inode
*inode
, int ioflags
)
1116 if (!pnfs_pageio_init_write(pgio
, inode
, ioflags
))
1117 nfs_pageio_init_write_mds(pgio
, inode
, ioflags
);
1121 * Handle a write reply that flushed part of a page.
1123 static void nfs_writeback_done_partial(struct rpc_task
*task
, void *calldata
)
1125 struct nfs_write_data
*data
= calldata
;
1127 dprintk("NFS: %5u write(%s/%lld %d@%lld)",
1129 data
->req
->wb_context
->dentry
->d_inode
->i_sb
->s_id
,
1131 NFS_FILEID(data
->req
->wb_context
->dentry
->d_inode
),
1132 data
->req
->wb_bytes
, (long long)req_offset(data
->req
));
1134 nfs_writeback_done(task
, data
);
1137 static void nfs_writeback_release_partial(void *calldata
)
1139 struct nfs_write_data
*data
= calldata
;
1140 struct nfs_page
*req
= data
->req
;
1141 struct page
*page
= req
->wb_page
;
1142 int status
= data
->task
.tk_status
;
1145 nfs_set_pageerror(page
);
1146 nfs_context_set_write_error(req
->wb_context
, status
);
1147 dprintk(", error = %d\n", status
);
1151 if (nfs_write_need_commit(data
)) {
1152 struct inode
*inode
= page
->mapping
->host
;
1154 spin_lock(&inode
->i_lock
);
1155 if (test_bit(PG_NEED_RESCHED
, &req
->wb_flags
)) {
1156 /* Do nothing we need to resend the writes */
1157 } else if (!test_and_set_bit(PG_NEED_COMMIT
, &req
->wb_flags
)) {
1158 memcpy(&req
->wb_verf
, &data
->verf
, sizeof(req
->wb_verf
));
1159 dprintk(" defer commit\n");
1160 } else if (memcmp(&req
->wb_verf
, &data
->verf
, sizeof(req
->wb_verf
))) {
1161 set_bit(PG_NEED_RESCHED
, &req
->wb_flags
);
1162 clear_bit(PG_NEED_COMMIT
, &req
->wb_flags
);
1163 dprintk(" server reboot detected\n");
1165 spin_unlock(&inode
->i_lock
);
1170 if (atomic_dec_and_test(&req
->wb_complete
))
1171 nfs_writepage_release(req
, data
);
1172 nfs_writedata_release(calldata
);
1175 void nfs_write_prepare(struct rpc_task
*task
, void *calldata
)
1177 struct nfs_write_data
*data
= calldata
;
1178 NFS_PROTO(data
->inode
)->write_rpc_prepare(task
, data
);
1181 static const struct rpc_call_ops nfs_write_partial_ops
= {
1182 .rpc_call_prepare
= nfs_write_prepare
,
1183 .rpc_call_done
= nfs_writeback_done_partial
,
1184 .rpc_release
= nfs_writeback_release_partial
,
1188 * Handle a write reply that flushes a whole page.
1190 * FIXME: There is an inherent race with invalidate_inode_pages and
1191 * writebacks since the page->count is kept > 1 for as long
1192 * as the page has a write request pending.
1194 static void nfs_writeback_done_full(struct rpc_task
*task
, void *calldata
)
1196 struct nfs_write_data
*data
= calldata
;
1198 nfs_writeback_done(task
, data
);
1201 static void nfs_writeback_release_full(void *calldata
)
1203 struct nfs_write_data
*data
= calldata
;
1204 int status
= data
->task
.tk_status
;
1206 /* Update attributes as result of writeback. */
1207 while (!list_empty(&data
->pages
)) {
1208 struct nfs_page
*req
= nfs_list_entry(data
->pages
.next
);
1209 struct page
*page
= req
->wb_page
;
1211 nfs_list_remove_request(req
);
1213 dprintk("NFS: %5u write (%s/%lld %d@%lld)",
1215 req
->wb_context
->dentry
->d_inode
->i_sb
->s_id
,
1216 (long long)NFS_FILEID(req
->wb_context
->dentry
->d_inode
),
1218 (long long)req_offset(req
));
1221 nfs_set_pageerror(page
);
1222 nfs_context_set_write_error(req
->wb_context
, status
);
1223 dprintk(", error = %d\n", status
);
1224 goto remove_request
;
1227 if (nfs_write_need_commit(data
)) {
1228 memcpy(&req
->wb_verf
, &data
->verf
, sizeof(req
->wb_verf
));
1229 nfs_mark_request_commit(req
, data
->lseg
);
1230 dprintk(" marked for commit\n");
1235 nfs_inode_remove_request(req
);
1237 nfs_unlock_request(req
);
1238 nfs_end_page_writeback(page
);
1240 nfs_writedata_release(calldata
);
1243 static const struct rpc_call_ops nfs_write_full_ops
= {
1244 .rpc_call_prepare
= nfs_write_prepare
,
1245 .rpc_call_done
= nfs_writeback_done_full
,
1246 .rpc_release
= nfs_writeback_release_full
,
1251 * This function is called when the WRITE call is complete.
1253 void nfs_writeback_done(struct rpc_task
*task
, struct nfs_write_data
*data
)
1255 struct nfs_writeargs
*argp
= &data
->args
;
1256 struct nfs_writeres
*resp
= &data
->res
;
1259 dprintk("NFS: %5u nfs_writeback_done (status %d)\n",
1260 task
->tk_pid
, task
->tk_status
);
1263 * ->write_done will attempt to use post-op attributes to detect
1264 * conflicting writes by other clients. A strict interpretation
1265 * of close-to-open would allow us to continue caching even if
1266 * another writer had changed the file, but some applications
1267 * depend on tighter cache coherency when writing.
1269 status
= NFS_PROTO(data
->inode
)->write_done(task
, data
);
1272 nfs_add_stats(data
->inode
, NFSIOS_SERVERWRITTENBYTES
, resp
->count
);
1274 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
1275 if (resp
->verf
->committed
< argp
->stable
&& task
->tk_status
>= 0) {
1276 /* We tried a write call, but the server did not
1277 * commit data to stable storage even though we
1279 * Note: There is a known bug in Tru64 < 5.0 in which
1280 * the server reports NFS_DATA_SYNC, but performs
1281 * NFS_FILE_SYNC. We therefore implement this checking
1282 * as a dprintk() in order to avoid filling syslog.
1284 static unsigned long complain
;
1286 /* Note this will print the MDS for a DS write */
1287 if (time_before(complain
, jiffies
)) {
1288 dprintk("NFS: faulty NFS server %s:"
1289 " (committed = %d) != (stable = %d)\n",
1290 NFS_SERVER(data
->inode
)->nfs_client
->cl_hostname
,
1291 resp
->verf
->committed
, argp
->stable
);
1292 complain
= jiffies
+ 300 * HZ
;
1296 /* Is this a short write? */
1297 if (task
->tk_status
>= 0 && resp
->count
< argp
->count
) {
1298 static unsigned long complain
;
1300 nfs_inc_stats(data
->inode
, NFSIOS_SHORTWRITE
);
1302 /* Has the server at least made some progress? */
1303 if (resp
->count
!= 0) {
1304 /* Was this an NFSv2 write or an NFSv3 stable write? */
1305 if (resp
->verf
->committed
!= NFS_UNSTABLE
) {
1306 /* Resend from where the server left off */
1307 data
->mds_offset
+= resp
->count
;
1308 argp
->offset
+= resp
->count
;
1309 argp
->pgbase
+= resp
->count
;
1310 argp
->count
-= resp
->count
;
1312 /* Resend as a stable write in order to avoid
1313 * headaches in the case of a server crash.
1315 argp
->stable
= NFS_FILE_SYNC
;
1317 rpc_restart_call_prepare(task
);
1320 if (time_before(complain
, jiffies
)) {
1322 "NFS: Server wrote zero bytes, expected %u.\n",
1324 complain
= jiffies
+ 300 * HZ
;
1326 /* Can't do anything about it except throw an error. */
1327 task
->tk_status
= -EIO
;
1333 #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
1334 static int nfs_commit_set_lock(struct nfs_inode
*nfsi
, int may_wait
)
1338 if (!test_and_set_bit(NFS_INO_COMMIT
, &nfsi
->flags
))
1342 ret
= out_of_line_wait_on_bit_lock(&nfsi
->flags
,
1344 nfs_wait_bit_killable
,
1346 return (ret
< 0) ? ret
: 1;
1349 void nfs_commit_clear_lock(struct nfs_inode
*nfsi
)
1351 clear_bit(NFS_INO_COMMIT
, &nfsi
->flags
);
1352 smp_mb__after_clear_bit();
1353 wake_up_bit(&nfsi
->flags
, NFS_INO_COMMIT
);
1355 EXPORT_SYMBOL_GPL(nfs_commit_clear_lock
);
1357 void nfs_commitdata_release(void *data
)
1359 struct nfs_write_data
*wdata
= data
;
1361 put_nfs_open_context(wdata
->args
.context
);
1362 nfs_commit_free(wdata
);
1364 EXPORT_SYMBOL_GPL(nfs_commitdata_release
);
1366 int nfs_initiate_commit(struct nfs_write_data
*data
, struct rpc_clnt
*clnt
,
1367 const struct rpc_call_ops
*call_ops
,
1370 struct rpc_task
*task
;
1371 int priority
= flush_task_priority(how
);
1372 struct rpc_message msg
= {
1373 .rpc_argp
= &data
->args
,
1374 .rpc_resp
= &data
->res
,
1375 .rpc_cred
= data
->cred
,
1377 struct rpc_task_setup task_setup_data
= {
1378 .task
= &data
->task
,
1380 .rpc_message
= &msg
,
1381 .callback_ops
= call_ops
,
1382 .callback_data
= data
,
1383 .workqueue
= nfsiod_workqueue
,
1384 .flags
= RPC_TASK_ASYNC
,
1385 .priority
= priority
,
1387 /* Set up the initial task struct. */
1388 NFS_PROTO(data
->inode
)->commit_setup(data
, &msg
);
1390 dprintk("NFS: %5u initiated commit call\n", data
->task
.tk_pid
);
1392 task
= rpc_run_task(&task_setup_data
);
1394 return PTR_ERR(task
);
1395 if (how
& FLUSH_SYNC
)
1396 rpc_wait_for_completion_task(task
);
1400 EXPORT_SYMBOL_GPL(nfs_initiate_commit
);
1403 * Set up the argument/result storage required for the RPC call.
1405 void nfs_init_commit(struct nfs_write_data
*data
,
1406 struct list_head
*head
,
1407 struct pnfs_layout_segment
*lseg
)
1409 struct nfs_page
*first
= nfs_list_entry(head
->next
);
1410 struct inode
*inode
= first
->wb_context
->dentry
->d_inode
;
1412 /* Set up the RPC argument and reply structs
1413 * NB: take care not to mess about with data->commit et al. */
1415 list_splice_init(head
, &data
->pages
);
1417 data
->inode
= inode
;
1418 data
->cred
= first
->wb_context
->cred
;
1419 data
->lseg
= lseg
; /* reference transferred */
1420 data
->mds_ops
= &nfs_commit_ops
;
1422 data
->args
.fh
= NFS_FH(data
->inode
);
1423 /* Note: we always request a commit of the entire inode */
1424 data
->args
.offset
= 0;
1425 data
->args
.count
= 0;
1426 data
->args
.context
= get_nfs_open_context(first
->wb_context
);
1427 data
->res
.count
= 0;
1428 data
->res
.fattr
= &data
->fattr
;
1429 data
->res
.verf
= &data
->verf
;
1430 nfs_fattr_init(&data
->fattr
);
1432 EXPORT_SYMBOL_GPL(nfs_init_commit
);
1434 void nfs_retry_commit(struct list_head
*page_list
,
1435 struct pnfs_layout_segment
*lseg
)
1437 struct nfs_page
*req
;
1439 while (!list_empty(page_list
)) {
1440 req
= nfs_list_entry(page_list
->next
);
1441 nfs_list_remove_request(req
);
1442 nfs_mark_request_commit(req
, lseg
);
1443 dec_zone_page_state(req
->wb_page
, NR_UNSTABLE_NFS
);
1444 dec_bdi_stat(req
->wb_page
->mapping
->backing_dev_info
,
1446 nfs_unlock_request(req
);
1449 EXPORT_SYMBOL_GPL(nfs_retry_commit
);
1452 * Commit dirty pages
1455 nfs_commit_list(struct inode
*inode
, struct list_head
*head
, int how
)
1457 struct nfs_write_data
*data
;
1459 data
= nfs_commitdata_alloc();
1464 /* Set up the argument struct */
1465 nfs_init_commit(data
, head
, NULL
);
1466 return nfs_initiate_commit(data
, NFS_CLIENT(inode
), data
->mds_ops
, how
);
1468 nfs_retry_commit(head
, NULL
);
1469 nfs_commit_clear_lock(NFS_I(inode
));
1474 * COMMIT call returned
1476 static void nfs_commit_done(struct rpc_task
*task
, void *calldata
)
1478 struct nfs_write_data
*data
= calldata
;
1480 dprintk("NFS: %5u nfs_commit_done (status %d)\n",
1481 task
->tk_pid
, task
->tk_status
);
1483 /* Call the NFS version-specific code */
1484 NFS_PROTO(data
->inode
)->commit_done(task
, data
);
1487 void nfs_commit_release_pages(struct nfs_write_data
*data
)
1489 struct nfs_page
*req
;
1490 int status
= data
->task
.tk_status
;
1492 while (!list_empty(&data
->pages
)) {
1493 req
= nfs_list_entry(data
->pages
.next
);
1494 nfs_list_remove_request(req
);
1495 nfs_clear_page_commit(req
->wb_page
);
1497 dprintk("NFS: commit (%s/%lld %d@%lld)",
1498 req
->wb_context
->dentry
->d_sb
->s_id
,
1499 (long long)NFS_FILEID(req
->wb_context
->dentry
->d_inode
),
1501 (long long)req_offset(req
));
1503 nfs_context_set_write_error(req
->wb_context
, status
);
1504 nfs_inode_remove_request(req
);
1505 dprintk(", error = %d\n", status
);
1509 /* Okay, COMMIT succeeded, apparently. Check the verifier
1510 * returned by the server against all stored verfs. */
1511 if (!memcmp(req
->wb_verf
.verifier
, data
->verf
.verifier
, sizeof(data
->verf
.verifier
))) {
1512 /* We have a match */
1513 nfs_inode_remove_request(req
);
1517 /* We have a mismatch. Write the page again */
1518 dprintk(" mismatch\n");
1519 nfs_mark_request_dirty(req
);
1521 nfs_unlock_request(req
);
1524 EXPORT_SYMBOL_GPL(nfs_commit_release_pages
);
1526 static void nfs_commit_release(void *calldata
)
1528 struct nfs_write_data
*data
= calldata
;
1530 nfs_commit_release_pages(data
);
1531 nfs_commit_clear_lock(NFS_I(data
->inode
));
1532 nfs_commitdata_release(calldata
);
1535 static const struct rpc_call_ops nfs_commit_ops
= {
1536 .rpc_call_prepare
= nfs_write_prepare
,
1537 .rpc_call_done
= nfs_commit_done
,
1538 .rpc_release
= nfs_commit_release
,
1541 int nfs_commit_inode(struct inode
*inode
, int how
)
1544 int may_wait
= how
& FLUSH_SYNC
;
1547 res
= nfs_commit_set_lock(NFS_I(inode
), may_wait
);
1549 goto out_mark_dirty
;
1550 res
= nfs_scan_commit(inode
, &head
);
1554 error
= pnfs_commit_list(inode
, &head
, how
);
1555 if (error
== PNFS_NOT_ATTEMPTED
)
1556 error
= nfs_commit_list(inode
, &head
, how
);
1560 goto out_mark_dirty
;
1561 error
= wait_on_bit(&NFS_I(inode
)->flags
,
1563 nfs_wait_bit_killable
,
1568 nfs_commit_clear_lock(NFS_I(inode
));
1570 /* Note: If we exit without ensuring that the commit is complete,
1571 * we must mark the inode as dirty. Otherwise, future calls to
1572 * sync_inode() with the WB_SYNC_ALL flag set will fail to ensure
1573 * that the data is on the disk.
1576 __mark_inode_dirty(inode
, I_DIRTY_DATASYNC
);
1580 static int nfs_commit_unstable_pages(struct inode
*inode
, struct writeback_control
*wbc
)
1582 struct nfs_inode
*nfsi
= NFS_I(inode
);
1583 int flags
= FLUSH_SYNC
;
1586 /* no commits means nothing needs to be done */
1590 if (wbc
->sync_mode
== WB_SYNC_NONE
) {
1591 /* Don't commit yet if this is a non-blocking flush and there
1592 * are a lot of outstanding writes for this mapping.
1594 if (nfsi
->ncommit
<= (nfsi
->npages
>> 1))
1595 goto out_mark_dirty
;
1597 /* don't wait for the COMMIT response */
1601 ret
= nfs_commit_inode(inode
, flags
);
1603 if (wbc
->sync_mode
== WB_SYNC_NONE
) {
1604 if (ret
< wbc
->nr_to_write
)
1605 wbc
->nr_to_write
-= ret
;
1607 wbc
->nr_to_write
= 0;
1612 __mark_inode_dirty(inode
, I_DIRTY_DATASYNC
);
1616 static int nfs_commit_unstable_pages(struct inode
*inode
, struct writeback_control
*wbc
)
1622 int nfs_write_inode(struct inode
*inode
, struct writeback_control
*wbc
)
1626 ret
= nfs_commit_unstable_pages(inode
, wbc
);
1627 if (ret
>= 0 && test_bit(NFS_INO_LAYOUTCOMMIT
, &NFS_I(inode
)->flags
)) {
1631 if (wbc
->sync_mode
== WB_SYNC_NONE
)
1634 status
= pnfs_layoutcommit_inode(inode
, sync
);
1642 * flush the inode to disk.
1644 int nfs_wb_all(struct inode
*inode
)
1646 struct writeback_control wbc
= {
1647 .sync_mode
= WB_SYNC_ALL
,
1648 .nr_to_write
= LONG_MAX
,
1650 .range_end
= LLONG_MAX
,
1653 return sync_inode(inode
, &wbc
);
1656 int nfs_wb_page_cancel(struct inode
*inode
, struct page
*page
)
1658 struct nfs_page
*req
;
1661 BUG_ON(!PageLocked(page
));
1663 wait_on_page_writeback(page
);
1664 req
= nfs_page_find_request(page
);
1667 if (nfs_lock_request_dontget(req
)) {
1668 nfs_clear_request_commit(req
);
1669 nfs_inode_remove_request(req
);
1671 * In case nfs_inode_remove_request has marked the
1672 * page as being dirty
1674 cancel_dirty_page(page
, PAGE_CACHE_SIZE
);
1675 nfs_unlock_request(req
);
1678 ret
= nfs_wait_on_request(req
);
1679 nfs_release_request(req
);
1687 * Write back all requests on one page - we do this before reading it.
1689 int nfs_wb_page(struct inode
*inode
, struct page
*page
)
1691 loff_t range_start
= page_offset(page
);
1692 loff_t range_end
= range_start
+ (loff_t
)(PAGE_CACHE_SIZE
- 1);
1693 struct writeback_control wbc
= {
1694 .sync_mode
= WB_SYNC_ALL
,
1696 .range_start
= range_start
,
1697 .range_end
= range_end
,
1702 wait_on_page_writeback(page
);
1703 if (clear_page_dirty_for_io(page
)) {
1704 ret
= nfs_writepage_locked(page
, &wbc
);
1709 if (!PagePrivate(page
))
1711 ret
= nfs_commit_inode(inode
, FLUSH_SYNC
);
1720 #ifdef CONFIG_MIGRATION
1721 int nfs_migrate_page(struct address_space
*mapping
, struct page
*newpage
,
1722 struct page
*page
, enum migrate_mode mode
)
1725 * If PagePrivate is set, then the page is currently associated with
1726 * an in-progress read or write request. Don't try to migrate it.
1728 * FIXME: we could do this in principle, but we'll need a way to ensure
1729 * that we can safely release the inode reference while holding
1732 if (PagePrivate(page
))
1735 nfs_fscache_release_page(page
, GFP_KERNEL
);
1737 return migrate_page(mapping
, newpage
, page
, mode
);
1741 int __init
nfs_init_writepagecache(void)
1743 nfs_wdata_cachep
= kmem_cache_create("nfs_write_data",
1744 sizeof(struct nfs_write_data
),
1745 0, SLAB_HWCACHE_ALIGN
,
1747 if (nfs_wdata_cachep
== NULL
)
1750 nfs_wdata_mempool
= mempool_create_slab_pool(MIN_POOL_WRITE
,
1752 if (nfs_wdata_mempool
== NULL
)
1755 nfs_commit_mempool
= mempool_create_slab_pool(MIN_POOL_COMMIT
,
1757 if (nfs_commit_mempool
== NULL
)
1761 * NFS congestion size, scale with available memory.
1773 * This allows larger machines to have larger/more transfers.
1774 * Limit the default to 256M
1776 nfs_congestion_kb
= (16*int_sqrt(totalram_pages
)) << (PAGE_SHIFT
-10);
1777 if (nfs_congestion_kb
> 256*1024)
1778 nfs_congestion_kb
= 256*1024;
1783 void nfs_destroy_writepagecache(void)
1785 mempool_destroy(nfs_commit_mempool
);
1786 mempool_destroy(nfs_wdata_mempool
);
1787 kmem_cache_destroy(nfs_wdata_cachep
);