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_lseg(wdata->lseg);
104
put_nfs_open_context(wdata->args.context);
105
nfs_writedata_free(wdata);
108
static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error)
112
set_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
115
static struct nfs_page *nfs_page_find_request_locked(struct page *page)
117
struct nfs_page *req = NULL;
119
if (PagePrivate(page)) {
120
req = (struct nfs_page *)page_private(page);
122
kref_get(&req->wb_kref);
127
static struct nfs_page *nfs_page_find_request(struct page *page)
129
struct inode *inode = page->mapping->host;
130
struct nfs_page *req = NULL;
132
spin_lock(&inode->i_lock);
133
req = nfs_page_find_request_locked(page);
134
spin_unlock(&inode->i_lock);
138
/* Adjust the file length if we're writing beyond the end */
139
static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count)
141
struct inode *inode = page->mapping->host;
145
spin_lock(&inode->i_lock);
146
i_size = i_size_read(inode);
147
end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
148
if (i_size > 0 && page->index < end_index)
150
end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + ((loff_t)offset+count);
153
i_size_write(inode, end);
154
nfs_inc_stats(inode, NFSIOS_EXTENDWRITE);
156
spin_unlock(&inode->i_lock);
159
/* A writeback failed: mark the page as bad, and invalidate the page cache */
160
static void nfs_set_pageerror(struct page *page)
163
nfs_zap_mapping(page->mapping->host, page->mapping);
166
/* We can set the PG_uptodate flag if we see that a write request
167
* covers the full page.
169
static void nfs_mark_uptodate(struct page *page, unsigned int base, unsigned int count)
171
if (PageUptodate(page))
175
if (count != nfs_page_length(page))
177
SetPageUptodate(page);
180
static int wb_priority(struct writeback_control *wbc)
182
if (wbc->for_reclaim)
183
return FLUSH_HIGHPRI | FLUSH_STABLE;
184
if (wbc->for_kupdate || wbc->for_background)
185
return FLUSH_LOWPRI | FLUSH_COND_STABLE;
186
return FLUSH_COND_STABLE;
190
* NFS congestion control
193
int nfs_congestion_kb;
195
#define NFS_CONGESTION_ON_THRESH (nfs_congestion_kb >> (PAGE_SHIFT-10))
196
#define NFS_CONGESTION_OFF_THRESH \
197
(NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2))
199
static int nfs_set_page_writeback(struct page *page)
201
int ret = test_set_page_writeback(page);
204
struct inode *inode = page->mapping->host;
205
struct nfs_server *nfss = NFS_SERVER(inode);
207
page_cache_get(page);
208
if (atomic_long_inc_return(&nfss->writeback) >
209
NFS_CONGESTION_ON_THRESH) {
210
set_bdi_congested(&nfss->backing_dev_info,
217
static void nfs_end_page_writeback(struct page *page)
219
struct inode *inode = page->mapping->host;
220
struct nfs_server *nfss = NFS_SERVER(inode);
222
end_page_writeback(page);
223
page_cache_release(page);
224
if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH)
225
clear_bdi_congested(&nfss->backing_dev_info, BLK_RW_ASYNC);
228
static struct nfs_page *nfs_find_and_lock_request(struct page *page, bool nonblock)
230
struct inode *inode = page->mapping->host;
231
struct nfs_page *req;
234
spin_lock(&inode->i_lock);
236
req = nfs_page_find_request_locked(page);
239
if (nfs_set_page_tag_locked(req))
241
/* Note: If we hold the page lock, as is the case in nfs_writepage,
242
* then the call to nfs_set_page_tag_locked() will always
243
* succeed provided that someone hasn't already marked the
244
* request as dirty (in which case we don't care).
246
spin_unlock(&inode->i_lock);
248
ret = nfs_wait_on_request(req);
251
nfs_release_request(req);
254
spin_lock(&inode->i_lock);
256
spin_unlock(&inode->i_lock);
261
* Find an associated nfs write request, and prepare to flush it out
262
* May return an error if the user signalled nfs_wait_on_request().
264
static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
265
struct page *page, bool nonblock)
267
struct nfs_page *req;
270
req = nfs_find_and_lock_request(page, nonblock);
277
ret = nfs_set_page_writeback(page);
279
BUG_ON(test_bit(PG_CLEAN, &req->wb_flags));
281
if (!nfs_pageio_add_request(pgio, req)) {
282
nfs_redirty_request(req);
283
ret = pgio->pg_error;
289
static int nfs_do_writepage(struct page *page, struct writeback_control *wbc, struct nfs_pageio_descriptor *pgio)
291
struct inode *inode = page->mapping->host;
294
nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE);
295
nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1);
297
nfs_pageio_cond_complete(pgio, page->index);
298
ret = nfs_page_async_flush(pgio, page, wbc->sync_mode == WB_SYNC_NONE);
299
if (ret == -EAGAIN) {
300
redirty_page_for_writepage(wbc, page);
307
* Write an mmapped page to the server.
309
static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc)
311
struct nfs_pageio_descriptor pgio;
314
nfs_pageio_init_write(&pgio, page->mapping->host, wb_priority(wbc));
315
err = nfs_do_writepage(page, wbc, &pgio);
316
nfs_pageio_complete(&pgio);
319
if (pgio.pg_error < 0)
320
return pgio.pg_error;
324
int nfs_writepage(struct page *page, struct writeback_control *wbc)
328
ret = nfs_writepage_locked(page, wbc);
333
static int nfs_writepages_callback(struct page *page, struct writeback_control *wbc, void *data)
337
ret = nfs_do_writepage(page, wbc, data);
342
int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
344
struct inode *inode = mapping->host;
345
unsigned long *bitlock = &NFS_I(inode)->flags;
346
struct nfs_pageio_descriptor pgio;
349
/* Stop dirtying of new pages while we sync */
350
err = wait_on_bit_lock(bitlock, NFS_INO_FLUSHING,
351
nfs_wait_bit_killable, TASK_KILLABLE);
355
nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES);
357
nfs_pageio_init_write(&pgio, inode, wb_priority(wbc));
358
err = write_cache_pages(mapping, wbc, nfs_writepages_callback, &pgio);
359
nfs_pageio_complete(&pgio);
361
clear_bit_unlock(NFS_INO_FLUSHING, bitlock);
362
smp_mb__after_clear_bit();
363
wake_up_bit(bitlock, NFS_INO_FLUSHING);
376
* Insert a write request into an inode
378
static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
380
struct nfs_inode *nfsi = NFS_I(inode);
383
error = radix_tree_preload(GFP_NOFS);
387
/* Lock the request! */
388
nfs_lock_request_dontget(req);
390
spin_lock(&inode->i_lock);
391
error = radix_tree_insert(&nfsi->nfs_page_tree, req->wb_index, req);
393
if (!nfsi->npages && nfs_have_delegation(inode, FMODE_WRITE))
395
set_bit(PG_MAPPED, &req->wb_flags);
396
SetPagePrivate(req->wb_page);
397
set_page_private(req->wb_page, (unsigned long)req);
399
kref_get(&req->wb_kref);
400
radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index,
401
NFS_PAGE_TAG_LOCKED);
402
spin_unlock(&inode->i_lock);
403
radix_tree_preload_end();
409
* Remove a write request from an inode
411
static void nfs_inode_remove_request(struct nfs_page *req)
413
struct inode *inode = req->wb_context->dentry->d_inode;
414
struct nfs_inode *nfsi = NFS_I(inode);
416
BUG_ON (!NFS_WBACK_BUSY(req));
418
spin_lock(&inode->i_lock);
419
set_page_private(req->wb_page, 0);
420
ClearPagePrivate(req->wb_page);
421
clear_bit(PG_MAPPED, &req->wb_flags);
422
radix_tree_delete(&nfsi->nfs_page_tree, req->wb_index);
424
spin_unlock(&inode->i_lock);
425
nfs_release_request(req);
429
nfs_mark_request_dirty(struct nfs_page *req)
431
__set_page_dirty_nobuffers(req->wb_page);
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->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
__set_page_dirty_nobuffers(page);
768
dprintk("NFS: nfs_updatepage returns %d (isize %lld)\n",
769
status, (long long)i_size_read(inode));
773
static void nfs_writepage_release(struct nfs_page *req,
774
struct nfs_write_data *data)
776
struct page *page = req->wb_page;
778
if (PageError(req->wb_page) || !nfs_reschedule_unstable_write(req, data))
779
nfs_inode_remove_request(req);
780
nfs_clear_page_tag_locked(req);
781
nfs_end_page_writeback(page);
784
static int flush_task_priority(int how)
786
switch (how & (FLUSH_HIGHPRI|FLUSH_LOWPRI)) {
788
return RPC_PRIORITY_HIGH;
790
return RPC_PRIORITY_LOW;
792
return RPC_PRIORITY_NORMAL;
795
int nfs_initiate_write(struct nfs_write_data *data,
796
struct rpc_clnt *clnt,
797
const struct rpc_call_ops *call_ops,
800
struct inode *inode = data->inode;
801
int priority = flush_task_priority(how);
802
struct rpc_task *task;
803
struct rpc_message msg = {
804
.rpc_argp = &data->args,
805
.rpc_resp = &data->res,
806
.rpc_cred = data->cred,
808
struct rpc_task_setup task_setup_data = {
812
.callback_ops = call_ops,
813
.callback_data = data,
814
.workqueue = nfsiod_workqueue,
815
.flags = RPC_TASK_ASYNC,
816
.priority = priority,
820
/* Set up the initial task struct. */
821
NFS_PROTO(inode)->write_setup(data, &msg);
823
dprintk("NFS: %5u initiated write call "
824
"(req %s/%lld, %u bytes @ offset %llu)\n",
827
(long long)NFS_FILEID(inode),
829
(unsigned long long)data->args.offset);
831
task = rpc_run_task(&task_setup_data);
836
if (how & FLUSH_SYNC) {
837
ret = rpc_wait_for_completion_task(task);
839
ret = task->tk_status;
845
EXPORT_SYMBOL_GPL(nfs_initiate_write);
848
* Set up the argument/result storage required for the RPC call.
850
static void nfs_write_rpcsetup(struct nfs_page *req,
851
struct nfs_write_data *data,
852
unsigned int count, unsigned int offset,
855
struct inode *inode = req->wb_context->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->dentry->d_inode;
862
data->cred = req->wb_context->cred;
864
data->args.fh = NFS_FH(inode);
865
data->args.offset = req_offset(req) + offset;
866
/* pnfs_set_layoutcommit needs this */
867
data->mds_offset = data->args.offset;
868
data->args.pgbase = req->wb_pgbase + offset;
869
data->args.pages = data->pagevec;
870
data->args.count = count;
871
data->args.context = get_nfs_open_context(req->wb_context);
872
data->args.lock_context = req->wb_lock_context;
873
data->args.stable = NFS_UNSTABLE;
874
switch (how & (FLUSH_STABLE | FLUSH_COND_STABLE)) {
877
case FLUSH_COND_STABLE:
878
if (nfs_need_commit(NFS_I(inode)))
881
data->args.stable = NFS_FILE_SYNC;
884
data->res.fattr = &data->fattr;
885
data->res.count = count;
886
data->res.verf = &data->verf;
887
nfs_fattr_init(&data->fattr);
890
static int nfs_do_write(struct nfs_write_data *data,
891
const struct rpc_call_ops *call_ops,
894
struct inode *inode = data->args.context->dentry->d_inode;
896
return nfs_initiate_write(data, NFS_CLIENT(inode), call_ops, how);
899
static int nfs_do_multiple_writes(struct list_head *head,
900
const struct rpc_call_ops *call_ops,
903
struct nfs_write_data *data;
906
while (!list_empty(head)) {
909
data = list_entry(head->next, struct nfs_write_data, list);
910
list_del_init(&data->list);
912
ret2 = nfs_do_write(data, call_ops, how);
919
/* If a nfs_flush_* function fails, it should remove reqs from @head and
920
* call this on each, which will prepare them to be retried on next
921
* writeback using standard nfs.
923
static void nfs_redirty_request(struct nfs_page *req)
925
struct page *page = req->wb_page;
927
nfs_mark_request_dirty(req);
928
nfs_clear_page_tag_locked(req);
929
nfs_end_page_writeback(page);
933
* Generate multiple small requests to write out a single
934
* contiguous dirty area on one page.
936
static int nfs_flush_multi(struct nfs_pageio_descriptor *desc, struct list_head *res)
938
struct nfs_page *req = nfs_list_entry(desc->pg_list.next);
939
struct page *page = req->wb_page;
940
struct nfs_write_data *data;
941
size_t wsize = desc->pg_bsize, nbytes;
946
nfs_list_remove_request(req);
948
if ((desc->pg_ioflags & FLUSH_COND_STABLE) &&
949
(desc->pg_moreio || NFS_I(desc->pg_inode)->ncommit ||
950
desc->pg_count > wsize))
951
desc->pg_ioflags &= ~FLUSH_COND_STABLE;
955
nbytes = desc->pg_count;
957
size_t len = min(nbytes, wsize);
959
data = nfs_writedata_alloc(1);
962
data->pagevec[0] = page;
963
nfs_write_rpcsetup(req, data, len, offset, desc->pg_ioflags);
964
list_add(&data->list, res);
968
} while (nbytes != 0);
969
atomic_set(&req->wb_complete, requests);
970
desc->pg_rpc_callops = &nfs_write_partial_ops;
974
while (!list_empty(res)) {
975
data = list_entry(res->next, struct nfs_write_data, list);
976
list_del(&data->list);
977
nfs_writedata_free(data);
979
nfs_redirty_request(req);
984
* Create an RPC task for the given write request and kick it.
985
* The page must have been locked by the caller.
987
* It may happen that the page we're passed is not marked dirty.
988
* This is the case if nfs_updatepage detects a conflicting request
989
* that has been written but not committed.
991
static int nfs_flush_one(struct nfs_pageio_descriptor *desc, struct list_head *res)
993
struct nfs_page *req;
995
struct nfs_write_data *data;
996
struct list_head *head = &desc->pg_list;
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
*pages++ = req->wb_page;
1017
req = nfs_list_entry(data->pages.next);
1019
if ((desc->pg_ioflags & FLUSH_COND_STABLE) &&
1020
(desc->pg_moreio || NFS_I(desc->pg_inode)->ncommit))
1021
desc->pg_ioflags &= ~FLUSH_COND_STABLE;
1023
/* Set up the argument struct */
1024
nfs_write_rpcsetup(req, data, desc->pg_count, 0, desc->pg_ioflags);
1025
list_add(&data->list, res);
1026
desc->pg_rpc_callops = &nfs_write_full_ops;
1031
int nfs_generic_flush(struct nfs_pageio_descriptor *desc, struct list_head *head)
1033
if (desc->pg_bsize < PAGE_CACHE_SIZE)
1034
return nfs_flush_multi(desc, head);
1035
return nfs_flush_one(desc, head);
1038
static int nfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
1043
ret = nfs_generic_flush(desc, &head);
1045
ret = nfs_do_multiple_writes(&head, desc->pg_rpc_callops,
1050
static const struct nfs_pageio_ops nfs_pageio_write_ops = {
1051
.pg_test = nfs_generic_pg_test,
1052
.pg_doio = nfs_generic_pg_writepages,
1055
static void nfs_pageio_init_write_mds(struct nfs_pageio_descriptor *pgio,
1056
struct inode *inode, int ioflags)
1058
nfs_pageio_init(pgio, inode, &nfs_pageio_write_ops,
1059
NFS_SERVER(inode)->wsize, ioflags);
1062
void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio)
1064
pgio->pg_ops = &nfs_pageio_write_ops;
1065
pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->wsize;
1067
EXPORT_SYMBOL_GPL(nfs_pageio_reset_write_mds);
1069
static void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
1070
struct inode *inode, int ioflags)
1072
if (!pnfs_pageio_init_write(pgio, inode, ioflags))
1073
nfs_pageio_init_write_mds(pgio, inode, ioflags);
1077
* Handle a write reply that flushed part of a page.
1079
static void nfs_writeback_done_partial(struct rpc_task *task, void *calldata)
1081
struct nfs_write_data *data = calldata;
1083
dprintk("NFS: %5u write(%s/%lld %d@%lld)",
1085
data->req->wb_context->dentry->d_inode->i_sb->s_id,
1087
NFS_FILEID(data->req->wb_context->dentry->d_inode),
1088
data->req->wb_bytes, (long long)req_offset(data->req));
1090
nfs_writeback_done(task, data);
1093
static void nfs_writeback_release_partial(void *calldata)
1095
struct nfs_write_data *data = calldata;
1096
struct nfs_page *req = data->req;
1097
struct page *page = req->wb_page;
1098
int status = data->task.tk_status;
1101
nfs_set_pageerror(page);
1102
nfs_context_set_write_error(req->wb_context, status);
1103
dprintk(", error = %d\n", status);
1107
if (nfs_write_need_commit(data)) {
1108
struct inode *inode = page->mapping->host;
1110
spin_lock(&inode->i_lock);
1111
if (test_bit(PG_NEED_RESCHED, &req->wb_flags)) {
1112
/* Do nothing we need to resend the writes */
1113
} else if (!test_and_set_bit(PG_NEED_COMMIT, &req->wb_flags)) {
1114
memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf));
1115
dprintk(" defer commit\n");
1116
} else if (memcmp(&req->wb_verf, &data->verf, sizeof(req->wb_verf))) {
1117
set_bit(PG_NEED_RESCHED, &req->wb_flags);
1118
clear_bit(PG_NEED_COMMIT, &req->wb_flags);
1119
dprintk(" server reboot detected\n");
1121
spin_unlock(&inode->i_lock);
1126
if (atomic_dec_and_test(&req->wb_complete))
1127
nfs_writepage_release(req, data);
1128
nfs_writedata_release(calldata);
1131
#if defined(CONFIG_NFS_V4_1)
1132
void nfs_write_prepare(struct rpc_task *task, void *calldata)
1134
struct nfs_write_data *data = calldata;
1136
if (nfs4_setup_sequence(NFS_SERVER(data->inode),
1137
&data->args.seq_args,
1138
&data->res.seq_res, 1, task))
1140
rpc_call_start(task);
1142
#endif /* CONFIG_NFS_V4_1 */
1144
static const struct rpc_call_ops nfs_write_partial_ops = {
1145
#if defined(CONFIG_NFS_V4_1)
1146
.rpc_call_prepare = nfs_write_prepare,
1147
#endif /* CONFIG_NFS_V4_1 */
1148
.rpc_call_done = nfs_writeback_done_partial,
1149
.rpc_release = nfs_writeback_release_partial,
1153
* Handle a write reply that flushes a whole page.
1155
* FIXME: There is an inherent race with invalidate_inode_pages and
1156
* writebacks since the page->count is kept > 1 for as long
1157
* as the page has a write request pending.
1159
static void nfs_writeback_done_full(struct rpc_task *task, void *calldata)
1161
struct nfs_write_data *data = calldata;
1163
nfs_writeback_done(task, data);
1166
static void nfs_writeback_release_full(void *calldata)
1168
struct nfs_write_data *data = calldata;
1169
int ret, status = data->task.tk_status;
1170
struct nfs_pageio_descriptor pgio;
1172
if (data->pnfs_error) {
1173
nfs_pageio_init_write_mds(&pgio, data->inode, FLUSH_STABLE);
1174
pgio.pg_recoalesce = 1;
1177
/* Update attributes as result of writeback. */
1178
while (!list_empty(&data->pages)) {
1179
struct nfs_page *req = nfs_list_entry(data->pages.next);
1180
struct page *page = req->wb_page;
1182
nfs_list_remove_request(req);
1184
dprintk("NFS: %5u write (%s/%lld %d@%lld)",
1186
req->wb_context->dentry->d_inode->i_sb->s_id,
1187
(long long)NFS_FILEID(req->wb_context->dentry->d_inode),
1189
(long long)req_offset(req));
1191
if (data->pnfs_error) {
1192
dprintk(", pnfs error = %d\n", data->pnfs_error);
1197
nfs_set_pageerror(page);
1198
nfs_context_set_write_error(req->wb_context, status);
1199
dprintk(", error = %d\n", status);
1200
goto remove_request;
1203
if (nfs_write_need_commit(data)) {
1204
memcpy(&req->wb_verf, &data->verf, sizeof(req->wb_verf));
1205
nfs_mark_request_commit(req, data->lseg);
1206
dprintk(" marked for commit\n");
1211
nfs_inode_remove_request(req);
1213
nfs_clear_page_tag_locked(req);
1214
nfs_end_page_writeback(page);
1215
if (data->pnfs_error) {
1217
nfs_pageio_cond_complete(&pgio, page->index);
1218
ret = nfs_page_async_flush(&pgio, page, 0);
1220
nfs_set_pageerror(page);
1221
dprintk("rewrite to MDS error = %d\n", ret);
1226
if (data->pnfs_error)
1227
nfs_pageio_complete(&pgio);
1228
nfs_writedata_release(calldata);
1231
static const struct rpc_call_ops nfs_write_full_ops = {
1232
#if defined(CONFIG_NFS_V4_1)
1233
.rpc_call_prepare = nfs_write_prepare,
1234
#endif /* CONFIG_NFS_V4_1 */
1235
.rpc_call_done = nfs_writeback_done_full,
1236
.rpc_release = nfs_writeback_release_full,
1241
* This function is called when the WRITE call is complete.
1243
void nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data)
1245
struct nfs_writeargs *argp = &data->args;
1246
struct nfs_writeres *resp = &data->res;
1249
dprintk("NFS: %5u nfs_writeback_done (status %d)\n",
1250
task->tk_pid, task->tk_status);
1253
* ->write_done will attempt to use post-op attributes to detect
1254
* conflicting writes by other clients. A strict interpretation
1255
* of close-to-open would allow us to continue caching even if
1256
* another writer had changed the file, but some applications
1257
* depend on tighter cache coherency when writing.
1259
status = NFS_PROTO(data->inode)->write_done(task, data);
1262
nfs_add_stats(data->inode, NFSIOS_SERVERWRITTENBYTES, resp->count);
1264
#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
1265
if (resp->verf->committed < argp->stable && task->tk_status >= 0) {
1266
/* We tried a write call, but the server did not
1267
* commit data to stable storage even though we
1269
* Note: There is a known bug in Tru64 < 5.0 in which
1270
* the server reports NFS_DATA_SYNC, but performs
1271
* NFS_FILE_SYNC. We therefore implement this checking
1272
* as a dprintk() in order to avoid filling syslog.
1274
static unsigned long complain;
1276
/* Note this will print the MDS for a DS write */
1277
if (time_before(complain, jiffies)) {
1278
dprintk("NFS: faulty NFS server %s:"
1279
" (committed = %d) != (stable = %d)\n",
1280
NFS_SERVER(data->inode)->nfs_client->cl_hostname,
1281
resp->verf->committed, argp->stable);
1282
complain = jiffies + 300 * HZ;
1286
/* Is this a short write? */
1287
if (task->tk_status >= 0 && resp->count < argp->count) {
1288
static unsigned long complain;
1290
nfs_inc_stats(data->inode, NFSIOS_SHORTWRITE);
1292
/* Has the server at least made some progress? */
1293
if (resp->count != 0) {
1294
/* Was this an NFSv2 write or an NFSv3 stable write? */
1295
if (resp->verf->committed != NFS_UNSTABLE) {
1296
/* Resend from where the server left off */
1297
data->mds_offset += resp->count;
1298
argp->offset += resp->count;
1299
argp->pgbase += resp->count;
1300
argp->count -= resp->count;
1302
/* Resend as a stable write in order to avoid
1303
* headaches in the case of a server crash.
1305
argp->stable = NFS_FILE_SYNC;
1307
rpc_restart_call_prepare(task);
1310
if (time_before(complain, jiffies)) {
1312
"NFS: Server wrote zero bytes, expected %u.\n",
1314
complain = jiffies + 300 * HZ;
1316
/* Can't do anything about it except throw an error. */
1317
task->tk_status = -EIO;
1323
#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
1324
static int nfs_commit_set_lock(struct nfs_inode *nfsi, int may_wait)
1328
if (!test_and_set_bit(NFS_INO_COMMIT, &nfsi->flags))
1332
ret = out_of_line_wait_on_bit_lock(&nfsi->flags,
1334
nfs_wait_bit_killable,
1336
return (ret < 0) ? ret : 1;
1339
void nfs_commit_clear_lock(struct nfs_inode *nfsi)
1341
clear_bit(NFS_INO_COMMIT, &nfsi->flags);
1342
smp_mb__after_clear_bit();
1343
wake_up_bit(&nfsi->flags, NFS_INO_COMMIT);
1345
EXPORT_SYMBOL_GPL(nfs_commit_clear_lock);
1347
void nfs_commitdata_release(void *data)
1349
struct nfs_write_data *wdata = data;
1351
put_lseg(wdata->lseg);
1352
put_nfs_open_context(wdata->args.context);
1353
nfs_commit_free(wdata);
1355
EXPORT_SYMBOL_GPL(nfs_commitdata_release);
1357
int nfs_initiate_commit(struct nfs_write_data *data, struct rpc_clnt *clnt,
1358
const struct rpc_call_ops *call_ops,
1361
struct rpc_task *task;
1362
int priority = flush_task_priority(how);
1363
struct rpc_message msg = {
1364
.rpc_argp = &data->args,
1365
.rpc_resp = &data->res,
1366
.rpc_cred = data->cred,
1368
struct rpc_task_setup task_setup_data = {
1369
.task = &data->task,
1371
.rpc_message = &msg,
1372
.callback_ops = call_ops,
1373
.callback_data = data,
1374
.workqueue = nfsiod_workqueue,
1375
.flags = RPC_TASK_ASYNC,
1376
.priority = priority,
1378
/* Set up the initial task struct. */
1379
NFS_PROTO(data->inode)->commit_setup(data, &msg);
1381
dprintk("NFS: %5u initiated commit call\n", data->task.tk_pid);
1383
task = rpc_run_task(&task_setup_data);
1385
return PTR_ERR(task);
1386
if (how & FLUSH_SYNC)
1387
rpc_wait_for_completion_task(task);
1391
EXPORT_SYMBOL_GPL(nfs_initiate_commit);
1394
* Set up the argument/result storage required for the RPC call.
1396
void nfs_init_commit(struct nfs_write_data *data,
1397
struct list_head *head,
1398
struct pnfs_layout_segment *lseg)
1400
struct nfs_page *first = nfs_list_entry(head->next);
1401
struct inode *inode = first->wb_context->dentry->d_inode;
1403
/* Set up the RPC argument and reply structs
1404
* NB: take care not to mess about with data->commit et al. */
1406
list_splice_init(head, &data->pages);
1408
data->inode = inode;
1409
data->cred = first->wb_context->cred;
1410
data->lseg = lseg; /* reference transferred */
1411
data->mds_ops = &nfs_commit_ops;
1413
data->args.fh = NFS_FH(data->inode);
1414
/* Note: we always request a commit of the entire inode */
1415
data->args.offset = 0;
1416
data->args.count = 0;
1417
data->args.context = get_nfs_open_context(first->wb_context);
1418
data->res.count = 0;
1419
data->res.fattr = &data->fattr;
1420
data->res.verf = &data->verf;
1421
nfs_fattr_init(&data->fattr);
1423
EXPORT_SYMBOL_GPL(nfs_init_commit);
1425
void nfs_retry_commit(struct list_head *page_list,
1426
struct pnfs_layout_segment *lseg)
1428
struct nfs_page *req;
1430
while (!list_empty(page_list)) {
1431
req = nfs_list_entry(page_list->next);
1432
nfs_list_remove_request(req);
1433
nfs_mark_request_commit(req, lseg);
1434
dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
1435
dec_bdi_stat(req->wb_page->mapping->backing_dev_info,
1437
nfs_clear_page_tag_locked(req);
1440
EXPORT_SYMBOL_GPL(nfs_retry_commit);
1443
* Commit dirty pages
1446
nfs_commit_list(struct inode *inode, struct list_head *head, int how)
1448
struct nfs_write_data *data;
1450
data = nfs_commitdata_alloc();
1455
/* Set up the argument struct */
1456
nfs_init_commit(data, head, NULL);
1457
return nfs_initiate_commit(data, NFS_CLIENT(inode), data->mds_ops, how);
1459
nfs_retry_commit(head, NULL);
1460
nfs_commit_clear_lock(NFS_I(inode));
1465
* COMMIT call returned
1467
static void nfs_commit_done(struct rpc_task *task, void *calldata)
1469
struct nfs_write_data *data = calldata;
1471
dprintk("NFS: %5u nfs_commit_done (status %d)\n",
1472
task->tk_pid, task->tk_status);
1474
/* Call the NFS version-specific code */
1475
NFS_PROTO(data->inode)->commit_done(task, data);
1478
void nfs_commit_release_pages(struct nfs_write_data *data)
1480
struct nfs_page *req;
1481
int status = data->task.tk_status;
1483
while (!list_empty(&data->pages)) {
1484
req = nfs_list_entry(data->pages.next);
1485
nfs_list_remove_request(req);
1486
nfs_clear_request_commit(req);
1488
dprintk("NFS: commit (%s/%lld %d@%lld)",
1489
req->wb_context->dentry->d_sb->s_id,
1490
(long long)NFS_FILEID(req->wb_context->dentry->d_inode),
1492
(long long)req_offset(req));
1494
nfs_context_set_write_error(req->wb_context, status);
1495
nfs_inode_remove_request(req);
1496
dprintk(", error = %d\n", status);
1500
/* Okay, COMMIT succeeded, apparently. Check the verifier
1501
* returned by the server against all stored verfs. */
1502
if (!memcmp(req->wb_verf.verifier, data->verf.verifier, sizeof(data->verf.verifier))) {
1503
/* We have a match */
1504
nfs_inode_remove_request(req);
1508
/* We have a mismatch. Write the page again */
1509
dprintk(" mismatch\n");
1510
nfs_mark_request_dirty(req);
1512
nfs_clear_page_tag_locked(req);
1515
EXPORT_SYMBOL_GPL(nfs_commit_release_pages);
1517
static void nfs_commit_release(void *calldata)
1519
struct nfs_write_data *data = calldata;
1521
nfs_commit_release_pages(data);
1522
nfs_commit_clear_lock(NFS_I(data->inode));
1523
nfs_commitdata_release(calldata);
1526
static const struct rpc_call_ops nfs_commit_ops = {
1527
#if defined(CONFIG_NFS_V4_1)
1528
.rpc_call_prepare = nfs_write_prepare,
1529
#endif /* CONFIG_NFS_V4_1 */
1530
.rpc_call_done = nfs_commit_done,
1531
.rpc_release = nfs_commit_release,
1534
int nfs_commit_inode(struct inode *inode, int how)
1537
int may_wait = how & FLUSH_SYNC;
1540
res = nfs_commit_set_lock(NFS_I(inode), may_wait);
1542
goto out_mark_dirty;
1543
res = nfs_scan_commit(inode, &head, 0, 0);
1547
error = pnfs_commit_list(inode, &head, how);
1548
if (error == PNFS_NOT_ATTEMPTED)
1549
error = nfs_commit_list(inode, &head, how);
1553
goto out_mark_dirty;
1554
error = wait_on_bit(&NFS_I(inode)->flags,
1556
nfs_wait_bit_killable,
1561
nfs_commit_clear_lock(NFS_I(inode));
1563
/* Note: If we exit without ensuring that the commit is complete,
1564
* we must mark the inode as dirty. Otherwise, future calls to
1565
* sync_inode() with the WB_SYNC_ALL flag set will fail to ensure
1566
* that the data is on the disk.
1569
__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
1573
static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc)
1575
struct nfs_inode *nfsi = NFS_I(inode);
1576
int flags = FLUSH_SYNC;
1579
/* no commits means nothing needs to be done */
1583
if (wbc->sync_mode == WB_SYNC_NONE) {
1584
/* Don't commit yet if this is a non-blocking flush and there
1585
* are a lot of outstanding writes for this mapping.
1587
if (nfsi->ncommit <= (nfsi->npages >> 1))
1588
goto out_mark_dirty;
1590
/* don't wait for the COMMIT response */
1594
ret = nfs_commit_inode(inode, flags);
1596
if (wbc->sync_mode == WB_SYNC_NONE) {
1597
if (ret < wbc->nr_to_write)
1598
wbc->nr_to_write -= ret;
1600
wbc->nr_to_write = 0;
1605
__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
1609
static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc)
1615
int nfs_write_inode(struct inode *inode, struct writeback_control *wbc)
1619
ret = nfs_commit_unstable_pages(inode, wbc);
1620
if (ret >= 0 && test_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(inode)->flags)) {
1624
if (wbc->sync_mode == WB_SYNC_NONE)
1627
status = pnfs_layoutcommit_inode(inode, sync);
1635
* flush the inode to disk.
1637
int nfs_wb_all(struct inode *inode)
1639
struct writeback_control wbc = {
1640
.sync_mode = WB_SYNC_ALL,
1641
.nr_to_write = LONG_MAX,
1643
.range_end = LLONG_MAX,
1646
return sync_inode(inode, &wbc);
1649
int nfs_wb_page_cancel(struct inode *inode, struct page *page)
1651
struct nfs_page *req;
1654
BUG_ON(!PageLocked(page));
1656
wait_on_page_writeback(page);
1657
req = nfs_page_find_request(page);
1660
if (nfs_lock_request_dontget(req)) {
1661
nfs_inode_remove_request(req);
1663
* In case nfs_inode_remove_request has marked the
1664
* page as being dirty
1666
cancel_dirty_page(page, PAGE_CACHE_SIZE);
1667
nfs_unlock_request(req);
1670
ret = nfs_wait_on_request(req);
1671
nfs_release_request(req);
1679
* Write back all requests on one page - we do this before reading it.
1681
int nfs_wb_page(struct inode *inode, struct page *page)
1683
loff_t range_start = page_offset(page);
1684
loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1);
1685
struct writeback_control wbc = {
1686
.sync_mode = WB_SYNC_ALL,
1688
.range_start = range_start,
1689
.range_end = range_end,
1694
wait_on_page_writeback(page);
1695
if (clear_page_dirty_for_io(page)) {
1696
ret = nfs_writepage_locked(page, &wbc);
1701
if (!PagePrivate(page))
1703
ret = nfs_commit_inode(inode, FLUSH_SYNC);
1712
#ifdef CONFIG_MIGRATION
1713
int nfs_migrate_page(struct address_space *mapping, struct page *newpage,
1717
* If PagePrivate is set, then the page is currently associated with
1718
* an in-progress read or write request. Don't try to migrate it.
1720
* FIXME: we could do this in principle, but we'll need a way to ensure
1721
* that we can safely release the inode reference while holding
1724
if (PagePrivate(page))
1727
nfs_fscache_release_page(page, GFP_KERNEL);
1729
return migrate_page(mapping, newpage, page);
1733
int __init nfs_init_writepagecache(void)
1735
nfs_wdata_cachep = kmem_cache_create("nfs_write_data",
1736
sizeof(struct nfs_write_data),
1737
0, SLAB_HWCACHE_ALIGN,
1739
if (nfs_wdata_cachep == NULL)
1742
nfs_wdata_mempool = mempool_create_slab_pool(MIN_POOL_WRITE,
1744
if (nfs_wdata_mempool == NULL)
1747
nfs_commit_mempool = mempool_create_slab_pool(MIN_POOL_COMMIT,
1749
if (nfs_commit_mempool == NULL)
1753
* NFS congestion size, scale with available memory.
1765
* This allows larger machines to have larger/more transfers.
1766
* Limit the default to 256M
1768
nfs_congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
1769
if (nfs_congestion_kb > 256*1024)
1770
nfs_congestion_kb = 256*1024;
1775
void nfs_destroy_writepagecache(void)
1777
mempool_destroy(nfs_commit_mempool);
1778
mempool_destroy(nfs_wdata_mempool);
1779
kmem_cache_destroy(nfs_wdata_cachep);