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"
36 #define NFSDBG_FACILITY NFSDBG_PAGECACHE
38 #define MIN_POOL_WRITE (32)
39 #define MIN_POOL_COMMIT (4)
42 * Local function declarations
44 static void nfs_redirty_request(struct nfs_page *req);
45 static const struct rpc_call_ops nfs_write_common_ops;
46 static const struct rpc_call_ops nfs_commit_ops;
47 static const struct nfs_pgio_completion_ops nfs_async_write_completion_ops;
48 static const struct nfs_commit_completion_ops nfs_commit_completion_ops;
50 static struct kmem_cache *nfs_wdata_cachep;
51 static mempool_t *nfs_wdata_mempool;
52 static struct kmem_cache *nfs_cdata_cachep;
53 static mempool_t *nfs_commit_mempool;
55 struct nfs_commit_data *nfs_commitdata_alloc(void)
57 struct nfs_commit_data *p = mempool_alloc(nfs_commit_mempool, GFP_NOIO);
60 memset(p, 0, sizeof(*p));
61 INIT_LIST_HEAD(&p->pages);
65 EXPORT_SYMBOL_GPL(nfs_commitdata_alloc);
67 void nfs_commit_free(struct nfs_commit_data *p)
69 mempool_free(p, nfs_commit_mempool);
71 EXPORT_SYMBOL_GPL(nfs_commit_free);
73 struct nfs_write_header *nfs_writehdr_alloc(void)
75 struct nfs_write_header *p = mempool_alloc(nfs_wdata_mempool, GFP_NOIO);
78 struct nfs_pgio_header *hdr = &p->header;
80 memset(p, 0, sizeof(*p));
81 INIT_LIST_HEAD(&hdr->pages);
82 INIT_LIST_HEAD(&hdr->rpc_list);
83 spin_lock_init(&hdr->lock);
84 atomic_set(&hdr->refcnt, 0);
89 EXPORT_SYMBOL_GPL(nfs_writehdr_alloc);
91 static struct nfs_write_data *nfs_writedata_alloc(struct nfs_pgio_header *hdr,
92 unsigned int pagecount)
94 struct nfs_write_data *data, *prealloc;
96 prealloc = &container_of(hdr, struct nfs_write_header, header)->rpc_data;
97 if (prealloc->header == NULL)
100 data = kzalloc(sizeof(*data), GFP_KERNEL);
104 if (nfs_pgarray_set(&data->pages, pagecount)) {
106 atomic_inc(&hdr->refcnt);
108 if (data != prealloc)
116 void nfs_writehdr_free(struct nfs_pgio_header *hdr)
118 struct nfs_write_header *whdr = container_of(hdr, struct nfs_write_header, header);
119 mempool_free(whdr, nfs_wdata_mempool);
121 EXPORT_SYMBOL_GPL(nfs_writehdr_free);
123 void nfs_writedata_release(struct nfs_write_data *wdata)
125 struct nfs_pgio_header *hdr = wdata->header;
126 struct nfs_write_header *write_header = container_of(hdr, struct nfs_write_header, header);
128 put_nfs_open_context(wdata->args.context);
129 if (wdata->pages.pagevec != wdata->pages.page_array)
130 kfree(wdata->pages.pagevec);
131 if (wdata == &write_header->rpc_data) {
132 wdata->header = NULL;
135 if (atomic_dec_and_test(&hdr->refcnt))
136 hdr->completion_ops->completion(hdr);
137 /* Note: we only free the rpc_task after callbacks are done.
138 * See the comment in rpc_free_task() for why
142 EXPORT_SYMBOL_GPL(nfs_writedata_release);
144 static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error)
148 set_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
151 static struct nfs_page *
152 nfs_page_find_request_locked(struct nfs_inode *nfsi, struct page *page)
154 struct nfs_page *req = NULL;
156 if (PagePrivate(page))
157 req = (struct nfs_page *)page_private(page);
158 else if (unlikely(PageSwapCache(page))) {
159 struct nfs_page *freq, *t;
161 /* Linearly search the commit list for the correct req */
162 list_for_each_entry_safe(freq, t, &nfsi->commit_info.list, wb_list) {
163 if (freq->wb_page == page) {
171 kref_get(&req->wb_kref);
176 static struct nfs_page *nfs_page_find_request(struct page *page)
178 struct inode *inode = page_file_mapping(page)->host;
179 struct nfs_page *req = NULL;
181 spin_lock(&inode->i_lock);
182 req = nfs_page_find_request_locked(NFS_I(inode), page);
183 spin_unlock(&inode->i_lock);
187 /* Adjust the file length if we're writing beyond the end */
188 static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count)
190 struct inode *inode = page_file_mapping(page)->host;
194 spin_lock(&inode->i_lock);
195 i_size = i_size_read(inode);
196 end_index = (i_size - 1) >> PAGE_CACHE_SHIFT;
197 if (i_size > 0 && page_file_index(page) < end_index)
199 end = page_file_offset(page) + ((loff_t)offset+count);
202 i_size_write(inode, end);
203 nfs_inc_stats(inode, NFSIOS_EXTENDWRITE);
205 spin_unlock(&inode->i_lock);
208 /* A writeback failed: mark the page as bad, and invalidate the page cache */
209 static void nfs_set_pageerror(struct page *page)
211 nfs_zap_mapping(page_file_mapping(page)->host, page_file_mapping(page));
214 /* We can set the PG_uptodate flag if we see that a write request
215 * covers the full page.
217 static void nfs_mark_uptodate(struct page *page, unsigned int base, unsigned int count)
219 if (PageUptodate(page))
223 if (count != nfs_page_length(page))
225 SetPageUptodate(page);
228 static int wb_priority(struct writeback_control *wbc)
230 if (wbc->for_reclaim)
231 return FLUSH_HIGHPRI | FLUSH_STABLE;
232 if (wbc->for_kupdate || wbc->for_background)
233 return FLUSH_LOWPRI | FLUSH_COND_STABLE;
234 return FLUSH_COND_STABLE;
238 * NFS congestion control
241 int nfs_congestion_kb;
243 #define NFS_CONGESTION_ON_THRESH (nfs_congestion_kb >> (PAGE_SHIFT-10))
244 #define NFS_CONGESTION_OFF_THRESH \
245 (NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2))
247 static void nfs_set_page_writeback(struct page *page)
249 struct nfs_server *nfss = NFS_SERVER(page_file_mapping(page)->host);
250 int ret = test_set_page_writeback(page);
252 WARN_ON_ONCE(ret != 0);
254 if (atomic_long_inc_return(&nfss->writeback) >
255 NFS_CONGESTION_ON_THRESH) {
256 set_bdi_congested(&nfss->backing_dev_info,
261 static void nfs_end_page_writeback(struct page *page)
263 struct inode *inode = page_file_mapping(page)->host;
264 struct nfs_server *nfss = NFS_SERVER(inode);
266 end_page_writeback(page);
267 if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH)
268 clear_bdi_congested(&nfss->backing_dev_info, BLK_RW_ASYNC);
271 static struct nfs_page *nfs_find_and_lock_request(struct page *page, bool nonblock)
273 struct inode *inode = page_file_mapping(page)->host;
274 struct nfs_page *req;
277 spin_lock(&inode->i_lock);
279 req = nfs_page_find_request_locked(NFS_I(inode), page);
282 if (nfs_lock_request(req))
284 /* Note: If we hold the page lock, as is the case in nfs_writepage,
285 * then the call to nfs_lock_request() will always
286 * succeed provided that someone hasn't already marked the
287 * request as dirty (in which case we don't care).
289 spin_unlock(&inode->i_lock);
291 ret = nfs_wait_on_request(req);
294 nfs_release_request(req);
297 spin_lock(&inode->i_lock);
299 spin_unlock(&inode->i_lock);
304 * Find an associated nfs write request, and prepare to flush it out
305 * May return an error if the user signalled nfs_wait_on_request().
307 static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
308 struct page *page, bool nonblock)
310 struct nfs_page *req;
313 req = nfs_find_and_lock_request(page, nonblock);
320 nfs_set_page_writeback(page);
321 WARN_ON_ONCE(test_bit(PG_CLEAN, &req->wb_flags));
324 if (!nfs_pageio_add_request(pgio, req)) {
325 nfs_redirty_request(req);
326 ret = pgio->pg_error;
332 static int nfs_do_writepage(struct page *page, struct writeback_control *wbc, struct nfs_pageio_descriptor *pgio)
334 struct inode *inode = page_file_mapping(page)->host;
337 nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE);
338 nfs_add_stats(inode, NFSIOS_WRITEPAGES, 1);
340 nfs_pageio_cond_complete(pgio, page_file_index(page));
341 ret = nfs_page_async_flush(pgio, page, wbc->sync_mode == WB_SYNC_NONE);
342 if (ret == -EAGAIN) {
343 redirty_page_for_writepage(wbc, page);
350 * Write an mmapped page to the server.
352 static int nfs_writepage_locked(struct page *page, struct writeback_control *wbc)
354 struct nfs_pageio_descriptor pgio;
357 NFS_PROTO(page_file_mapping(page)->host)->write_pageio_init(&pgio,
360 &nfs_async_write_completion_ops);
361 err = nfs_do_writepage(page, wbc, &pgio);
362 nfs_pageio_complete(&pgio);
365 if (pgio.pg_error < 0)
366 return pgio.pg_error;
370 int nfs_writepage(struct page *page, struct writeback_control *wbc)
374 ret = nfs_writepage_locked(page, wbc);
379 static int nfs_writepages_callback(struct page *page, struct writeback_control *wbc, void *data)
383 ret = nfs_do_writepage(page, wbc, data);
388 int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
390 struct inode *inode = mapping->host;
391 unsigned long *bitlock = &NFS_I(inode)->flags;
392 struct nfs_pageio_descriptor pgio;
395 /* Stop dirtying of new pages while we sync */
396 err = wait_on_bit_lock(bitlock, NFS_INO_FLUSHING,
397 nfs_wait_bit_killable, TASK_KILLABLE);
401 nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGES);
403 NFS_PROTO(inode)->write_pageio_init(&pgio, inode, wb_priority(wbc), &nfs_async_write_completion_ops);
404 err = write_cache_pages(mapping, wbc, nfs_writepages_callback, &pgio);
405 nfs_pageio_complete(&pgio);
407 clear_bit_unlock(NFS_INO_FLUSHING, bitlock);
408 smp_mb__after_clear_bit();
409 wake_up_bit(bitlock, NFS_INO_FLUSHING);
422 * Insert a write request into an inode
424 static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
426 struct nfs_inode *nfsi = NFS_I(inode);
428 /* Lock the request! */
429 nfs_lock_request(req);
431 spin_lock(&inode->i_lock);
432 if (!nfsi->npages && NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE))
435 * Swap-space should not get truncated. Hence no need to plug the race
436 * with invalidate/truncate.
438 if (likely(!PageSwapCache(req->wb_page))) {
439 set_bit(PG_MAPPED, &req->wb_flags);
440 SetPagePrivate(req->wb_page);
441 set_page_private(req->wb_page, (unsigned long)req);
444 kref_get(&req->wb_kref);
445 spin_unlock(&inode->i_lock);
449 * Remove a write request from an inode
451 static void nfs_inode_remove_request(struct nfs_page *req)
453 struct inode *inode = req->wb_context->dentry->d_inode;
454 struct nfs_inode *nfsi = NFS_I(inode);
456 spin_lock(&inode->i_lock);
457 if (likely(!PageSwapCache(req->wb_page))) {
458 set_page_private(req->wb_page, 0);
459 ClearPagePrivate(req->wb_page);
460 clear_bit(PG_MAPPED, &req->wb_flags);
463 spin_unlock(&inode->i_lock);
464 nfs_release_request(req);
468 nfs_mark_request_dirty(struct nfs_page *req)
470 __set_page_dirty_nobuffers(req->wb_page);
473 #if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
475 * nfs_request_add_commit_list - add request to a commit list
476 * @req: pointer to a struct nfs_page
477 * @dst: commit list head
478 * @cinfo: holds list lock and accounting info
480 * This sets the PG_CLEAN bit, updates the cinfo count of
481 * number of outstanding requests requiring a commit as well as
484 * The caller must _not_ hold the cinfo->lock, but must be
485 * holding the nfs_page lock.
488 nfs_request_add_commit_list(struct nfs_page *req, struct list_head *dst,
489 struct nfs_commit_info *cinfo)
491 set_bit(PG_CLEAN, &(req)->wb_flags);
492 spin_lock(cinfo->lock);
493 nfs_list_add_request(req, dst);
494 cinfo->mds->ncommit++;
495 spin_unlock(cinfo->lock);
497 inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
498 inc_bdi_stat(page_file_mapping(req->wb_page)->backing_dev_info,
500 __mark_inode_dirty(req->wb_context->dentry->d_inode,
504 EXPORT_SYMBOL_GPL(nfs_request_add_commit_list);
507 * nfs_request_remove_commit_list - Remove request from a commit list
508 * @req: pointer to a nfs_page
509 * @cinfo: holds list lock and accounting info
511 * This clears the PG_CLEAN bit, and updates the cinfo's count of
512 * number of outstanding requests requiring a commit
513 * It does not update the MM page stats.
515 * The caller _must_ hold the cinfo->lock and the nfs_page lock.
518 nfs_request_remove_commit_list(struct nfs_page *req,
519 struct nfs_commit_info *cinfo)
521 if (!test_and_clear_bit(PG_CLEAN, &(req)->wb_flags))
523 nfs_list_remove_request(req);
524 cinfo->mds->ncommit--;
526 EXPORT_SYMBOL_GPL(nfs_request_remove_commit_list);
528 static void nfs_init_cinfo_from_inode(struct nfs_commit_info *cinfo,
531 cinfo->lock = &inode->i_lock;
532 cinfo->mds = &NFS_I(inode)->commit_info;
533 cinfo->ds = pnfs_get_ds_info(inode);
535 cinfo->completion_ops = &nfs_commit_completion_ops;
538 void nfs_init_cinfo(struct nfs_commit_info *cinfo,
540 struct nfs_direct_req *dreq)
543 nfs_init_cinfo_from_dreq(cinfo, dreq);
545 nfs_init_cinfo_from_inode(cinfo, inode);
547 EXPORT_SYMBOL_GPL(nfs_init_cinfo);
550 * Add a request to the inode's commit list.
553 nfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg,
554 struct nfs_commit_info *cinfo)
556 if (pnfs_mark_request_commit(req, lseg, cinfo))
558 nfs_request_add_commit_list(req, &cinfo->mds->list, cinfo);
562 nfs_clear_page_commit(struct page *page)
564 dec_zone_page_state(page, NR_UNSTABLE_NFS);
565 dec_bdi_stat(page_file_mapping(page)->backing_dev_info, BDI_RECLAIMABLE);
569 nfs_clear_request_commit(struct nfs_page *req)
571 if (test_bit(PG_CLEAN, &req->wb_flags)) {
572 struct inode *inode = req->wb_context->dentry->d_inode;
573 struct nfs_commit_info cinfo;
575 nfs_init_cinfo_from_inode(&cinfo, inode);
576 if (!pnfs_clear_request_commit(req, &cinfo)) {
577 spin_lock(cinfo.lock);
578 nfs_request_remove_commit_list(req, &cinfo);
579 spin_unlock(cinfo.lock);
581 nfs_clear_page_commit(req->wb_page);
586 int nfs_write_need_commit(struct nfs_write_data *data)
588 if (data->verf.committed == NFS_DATA_SYNC)
589 return data->header->lseg == NULL;
590 return data->verf.committed != NFS_FILE_SYNC;
594 static void nfs_init_cinfo_from_inode(struct nfs_commit_info *cinfo,
599 void nfs_init_cinfo(struct nfs_commit_info *cinfo,
601 struct nfs_direct_req *dreq)
606 nfs_mark_request_commit(struct nfs_page *req, struct pnfs_layout_segment *lseg,
607 struct nfs_commit_info *cinfo)
612 nfs_clear_request_commit(struct nfs_page *req)
617 int nfs_write_need_commit(struct nfs_write_data *data)
624 static void nfs_write_completion(struct nfs_pgio_header *hdr)
626 struct nfs_commit_info cinfo;
627 unsigned long bytes = 0;
629 if (test_bit(NFS_IOHDR_REDO, &hdr->flags))
631 nfs_init_cinfo_from_inode(&cinfo, hdr->inode);
632 while (!list_empty(&hdr->pages)) {
633 struct nfs_page *req = nfs_list_entry(hdr->pages.next);
635 bytes += req->wb_bytes;
636 nfs_list_remove_request(req);
637 if (test_bit(NFS_IOHDR_ERROR, &hdr->flags) &&
638 (hdr->good_bytes < bytes)) {
639 nfs_set_pageerror(req->wb_page);
640 nfs_context_set_write_error(req->wb_context, hdr->error);
643 if (test_bit(NFS_IOHDR_NEED_RESCHED, &hdr->flags)) {
644 nfs_mark_request_dirty(req);
647 if (test_bit(NFS_IOHDR_NEED_COMMIT, &hdr->flags)) {
648 memcpy(&req->wb_verf, &hdr->verf->verifier, sizeof(req->wb_verf));
649 nfs_mark_request_commit(req, hdr->lseg, &cinfo);
653 nfs_inode_remove_request(req);
655 nfs_unlock_request(req);
656 nfs_end_page_writeback(req->wb_page);
657 nfs_release_request(req);
663 #if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
665 nfs_reqs_to_commit(struct nfs_commit_info *cinfo)
667 return cinfo->mds->ncommit;
670 /* cinfo->lock held by caller */
672 nfs_scan_commit_list(struct list_head *src, struct list_head *dst,
673 struct nfs_commit_info *cinfo, int max)
675 struct nfs_page *req, *tmp;
678 list_for_each_entry_safe(req, tmp, src, wb_list) {
679 if (!nfs_lock_request(req))
681 kref_get(&req->wb_kref);
682 if (cond_resched_lock(cinfo->lock))
683 list_safe_reset_next(req, tmp, wb_list);
684 nfs_request_remove_commit_list(req, cinfo);
685 nfs_list_add_request(req, dst);
687 if ((ret == max) && !cinfo->dreq)
694 * nfs_scan_commit - Scan an inode for commit requests
695 * @inode: NFS inode to scan
696 * @dst: mds destination list
697 * @cinfo: mds and ds lists of reqs ready to commit
699 * Moves requests from the inode's 'commit' request list.
700 * The requests are *not* checked to ensure that they form a contiguous set.
703 nfs_scan_commit(struct inode *inode, struct list_head *dst,
704 struct nfs_commit_info *cinfo)
708 spin_lock(cinfo->lock);
709 if (cinfo->mds->ncommit > 0) {
710 const int max = INT_MAX;
712 ret = nfs_scan_commit_list(&cinfo->mds->list, dst,
714 ret += pnfs_scan_commit_lists(inode, cinfo, max - ret);
716 spin_unlock(cinfo->lock);
721 static unsigned long nfs_reqs_to_commit(struct nfs_commit_info *cinfo)
726 int nfs_scan_commit(struct inode *inode, struct list_head *dst,
727 struct nfs_commit_info *cinfo)
734 * Search for an existing write request, and attempt to update
735 * it to reflect a new dirty region on a given page.
737 * If the attempt fails, then the existing request is flushed out
740 static struct nfs_page *nfs_try_to_update_request(struct inode *inode,
745 struct nfs_page *req;
750 if (!PagePrivate(page))
753 end = offset + bytes;
754 spin_lock(&inode->i_lock);
757 req = nfs_page_find_request_locked(NFS_I(inode), page);
761 rqend = req->wb_offset + req->wb_bytes;
763 * Tell the caller to flush out the request if
764 * the offsets are non-contiguous.
765 * Note: nfs_flush_incompatible() will already
766 * have flushed out requests having wrong owners.
769 || end < req->wb_offset)
772 if (nfs_lock_request(req))
775 /* The request is locked, so wait and then retry */
776 spin_unlock(&inode->i_lock);
777 error = nfs_wait_on_request(req);
778 nfs_release_request(req);
781 spin_lock(&inode->i_lock);
784 /* Okay, the request matches. Update the region */
785 if (offset < req->wb_offset) {
786 req->wb_offset = offset;
787 req->wb_pgbase = offset;
790 req->wb_bytes = end - req->wb_offset;
792 req->wb_bytes = rqend - req->wb_offset;
794 spin_unlock(&inode->i_lock);
796 nfs_clear_request_commit(req);
799 spin_unlock(&inode->i_lock);
800 nfs_release_request(req);
801 error = nfs_wb_page(inode, page);
803 return ERR_PTR(error);
807 * Try to update an existing write request, or create one if there is none.
809 * Note: Should always be called with the Page Lock held to prevent races
810 * if we have to add a new request. Also assumes that the caller has
811 * already called nfs_flush_incompatible() if necessary.
813 static struct nfs_page * nfs_setup_write_request(struct nfs_open_context* ctx,
814 struct page *page, unsigned int offset, unsigned int bytes)
816 struct inode *inode = page_file_mapping(page)->host;
817 struct nfs_page *req;
819 req = nfs_try_to_update_request(inode, page, offset, bytes);
822 req = nfs_create_request(ctx, inode, page, offset, bytes);
825 nfs_inode_add_request(inode, req);
830 static int nfs_writepage_setup(struct nfs_open_context *ctx, struct page *page,
831 unsigned int offset, unsigned int count)
833 struct nfs_page *req;
835 req = nfs_setup_write_request(ctx, page, offset, count);
838 /* Update file length */
839 nfs_grow_file(page, offset, count);
840 nfs_mark_uptodate(page, req->wb_pgbase, req->wb_bytes);
841 nfs_mark_request_dirty(req);
842 nfs_unlock_and_release_request(req);
846 int nfs_flush_incompatible(struct file *file, struct page *page)
848 struct nfs_open_context *ctx = nfs_file_open_context(file);
849 struct nfs_lock_context *l_ctx;
850 struct nfs_page *req;
851 int do_flush, status;
853 * Look for a request corresponding to this page. If there
854 * is one, and it belongs to another file, we flush it out
855 * before we try to copy anything into the page. Do this
856 * due to the lack of an ACCESS-type call in NFSv2.
857 * Also do the same if we find a request from an existing
861 req = nfs_page_find_request(page);
864 l_ctx = req->wb_lock_context;
865 do_flush = req->wb_page != page || req->wb_context != ctx;
866 if (l_ctx && ctx->dentry->d_inode->i_flock != NULL) {
867 do_flush |= l_ctx->lockowner.l_owner != current->files
868 || l_ctx->lockowner.l_pid != current->tgid;
870 nfs_release_request(req);
873 status = nfs_wb_page(page_file_mapping(page)->host, page);
874 } while (status == 0);
879 * Avoid buffered writes when a open context credential's key would
882 * Returns -EACCES if the key will expire within RPC_KEY_EXPIRE_FAIL.
884 * Return 0 and set a credential flag which triggers the inode to flush
885 * and performs NFS_FILE_SYNC writes if the key will expired within
886 * RPC_KEY_EXPIRE_TIMEO.
889 nfs_key_timeout_notify(struct file *filp, struct inode *inode)
891 struct nfs_open_context *ctx = nfs_file_open_context(filp);
892 struct rpc_auth *auth = NFS_SERVER(inode)->client->cl_auth;
894 return rpcauth_key_timeout_notify(auth, ctx->cred);
898 * Test if the open context credential key is marked to expire soon.
900 bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx)
902 return rpcauth_cred_key_to_expire(ctx->cred);
906 * If the page cache is marked as unsafe or invalid, then we can't rely on
907 * the PageUptodate() flag. In this case, we will need to turn off
908 * write optimisations that depend on the page contents being correct.
910 static bool nfs_write_pageuptodate(struct page *page, struct inode *inode)
912 if (nfs_have_delegated_attributes(inode))
914 if (NFS_I(inode)->cache_validity & (NFS_INO_INVALID_DATA|NFS_INO_REVAL_PAGECACHE))
917 return PageUptodate(page) != 0;
920 /* If we know the page is up to date, and we're not using byte range locks (or
921 * if we have the whole file locked for writing), it may be more efficient to
922 * extend the write to cover the entire page in order to avoid fragmentation
925 * If the file is opened for synchronous writes then we can just skip the rest
928 static int nfs_can_extend_write(struct file *file, struct page *page, struct inode *inode)
930 if (file->f_flags & O_DSYNC)
932 if (!nfs_write_pageuptodate(page, inode))
934 if (NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE))
936 if (inode->i_flock == NULL || (inode->i_flock->fl_start == 0 &&
937 inode->i_flock->fl_end == OFFSET_MAX &&
938 inode->i_flock->fl_type != F_RDLCK))
944 * Update and possibly write a cached page of an NFS file.
946 * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad
947 * things with a page scheduled for an RPC call (e.g. invalidate it).
949 int nfs_updatepage(struct file *file, struct page *page,
950 unsigned int offset, unsigned int count)
952 struct nfs_open_context *ctx = nfs_file_open_context(file);
953 struct inode *inode = page_file_mapping(page)->host;
956 nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE);
958 dprintk("NFS: nfs_updatepage(%pD2 %d@%lld)\n",
959 file, count, (long long)(page_file_offset(page) + offset));
961 if (nfs_can_extend_write(file, page, inode)) {
962 count = max(count + offset, nfs_page_length(page));
966 status = nfs_writepage_setup(ctx, page, offset, count);
968 nfs_set_pageerror(page);
970 __set_page_dirty_nobuffers(page);
972 dprintk("NFS: nfs_updatepage returns %d (isize %lld)\n",
973 status, (long long)i_size_read(inode));
977 static int flush_task_priority(int how)
979 switch (how & (FLUSH_HIGHPRI|FLUSH_LOWPRI)) {
981 return RPC_PRIORITY_HIGH;
983 return RPC_PRIORITY_LOW;
985 return RPC_PRIORITY_NORMAL;
988 int nfs_initiate_write(struct rpc_clnt *clnt,
989 struct nfs_write_data *data,
990 const struct rpc_call_ops *call_ops,
993 struct inode *inode = data->header->inode;
994 int priority = flush_task_priority(how);
995 struct rpc_task *task;
996 struct rpc_message msg = {
997 .rpc_argp = &data->args,
998 .rpc_resp = &data->res,
999 .rpc_cred = data->header->cred,
1001 struct rpc_task_setup task_setup_data = {
1003 .task = &data->task,
1004 .rpc_message = &msg,
1005 .callback_ops = call_ops,
1006 .callback_data = data,
1007 .workqueue = nfsiod_workqueue,
1008 .flags = RPC_TASK_ASYNC | flags,
1009 .priority = priority,
1013 /* Set up the initial task struct. */
1014 NFS_PROTO(inode)->write_setup(data, &msg);
1016 dprintk("NFS: %5u initiated write call "
1017 "(req %s/%llu, %u bytes @ offset %llu)\n",
1020 (unsigned long long)NFS_FILEID(inode),
1022 (unsigned long long)data->args.offset);
1024 nfs4_state_protect_write(NFS_SERVER(inode)->nfs_client,
1025 &task_setup_data.rpc_client, &msg, data);
1027 task = rpc_run_task(&task_setup_data);
1029 ret = PTR_ERR(task);
1032 if (how & FLUSH_SYNC) {
1033 ret = rpc_wait_for_completion_task(task);
1035 ret = task->tk_status;
1041 EXPORT_SYMBOL_GPL(nfs_initiate_write);
1044 * Set up the argument/result storage required for the RPC call.
1046 static void nfs_write_rpcsetup(struct nfs_write_data *data,
1047 unsigned int count, unsigned int offset,
1048 int how, struct nfs_commit_info *cinfo)
1050 struct nfs_page *req = data->header->req;
1052 /* Set up the RPC argument and reply structs
1053 * NB: take care not to mess about with data->commit et al. */
1055 data->args.fh = NFS_FH(data->header->inode);
1056 data->args.offset = req_offset(req) + offset;
1057 /* pnfs_set_layoutcommit needs this */
1058 data->mds_offset = data->args.offset;
1059 data->args.pgbase = req->wb_pgbase + offset;
1060 data->args.pages = data->pages.pagevec;
1061 data->args.count = count;
1062 data->args.context = get_nfs_open_context(req->wb_context);
1063 data->args.lock_context = req->wb_lock_context;
1064 data->args.stable = NFS_UNSTABLE;
1065 switch (how & (FLUSH_STABLE | FLUSH_COND_STABLE)) {
1068 case FLUSH_COND_STABLE:
1069 if (nfs_reqs_to_commit(cinfo))
1072 data->args.stable = NFS_FILE_SYNC;
1075 data->res.fattr = &data->fattr;
1076 data->res.count = count;
1077 data->res.verf = &data->verf;
1078 nfs_fattr_init(&data->fattr);
1081 static int nfs_do_write(struct nfs_write_data *data,
1082 const struct rpc_call_ops *call_ops,
1085 struct inode *inode = data->header->inode;
1087 return nfs_initiate_write(NFS_CLIENT(inode), data, call_ops, how, 0);
1090 static int nfs_do_multiple_writes(struct list_head *head,
1091 const struct rpc_call_ops *call_ops,
1094 struct nfs_write_data *data;
1097 while (!list_empty(head)) {
1100 data = list_first_entry(head, struct nfs_write_data, list);
1101 list_del_init(&data->list);
1103 ret2 = nfs_do_write(data, call_ops, how);
1110 /* If a nfs_flush_* function fails, it should remove reqs from @head and
1111 * call this on each, which will prepare them to be retried on next
1112 * writeback using standard nfs.
1114 static void nfs_redirty_request(struct nfs_page *req)
1116 nfs_mark_request_dirty(req);
1117 nfs_unlock_request(req);
1118 nfs_end_page_writeback(req->wb_page);
1119 nfs_release_request(req);
1122 static void nfs_async_write_error(struct list_head *head)
1124 struct nfs_page *req;
1126 while (!list_empty(head)) {
1127 req = nfs_list_entry(head->next);
1128 nfs_list_remove_request(req);
1129 nfs_redirty_request(req);
1133 static const struct nfs_pgio_completion_ops nfs_async_write_completion_ops = {
1134 .error_cleanup = nfs_async_write_error,
1135 .completion = nfs_write_completion,
1138 static void nfs_flush_error(struct nfs_pageio_descriptor *desc,
1139 struct nfs_pgio_header *hdr)
1141 set_bit(NFS_IOHDR_REDO, &hdr->flags);
1142 while (!list_empty(&hdr->rpc_list)) {
1143 struct nfs_write_data *data = list_first_entry(&hdr->rpc_list,
1144 struct nfs_write_data, list);
1145 list_del(&data->list);
1146 nfs_writedata_release(data);
1148 desc->pg_completion_ops->error_cleanup(&desc->pg_list);
1152 * Generate multiple small requests to write out a single
1153 * contiguous dirty area on one page.
1155 static int nfs_flush_multi(struct nfs_pageio_descriptor *desc,
1156 struct nfs_pgio_header *hdr)
1158 struct nfs_page *req = hdr->req;
1159 struct page *page = req->wb_page;
1160 struct nfs_write_data *data;
1161 size_t wsize = desc->pg_bsize, nbytes;
1162 unsigned int offset;
1164 struct nfs_commit_info cinfo;
1166 nfs_init_cinfo(&cinfo, desc->pg_inode, desc->pg_dreq);
1168 if ((desc->pg_ioflags & FLUSH_COND_STABLE) &&
1169 (desc->pg_moreio || nfs_reqs_to_commit(&cinfo) ||
1170 desc->pg_count > wsize))
1171 desc->pg_ioflags &= ~FLUSH_COND_STABLE;
1175 nbytes = desc->pg_count;
1177 size_t len = min(nbytes, wsize);
1179 data = nfs_writedata_alloc(hdr, 1);
1181 nfs_flush_error(desc, hdr);
1184 data->pages.pagevec[0] = page;
1185 nfs_write_rpcsetup(data, len, offset, desc->pg_ioflags, &cinfo);
1186 list_add(&data->list, &hdr->rpc_list);
1190 } while (nbytes != 0);
1191 nfs_list_remove_request(req);
1192 nfs_list_add_request(req, &hdr->pages);
1193 desc->pg_rpc_callops = &nfs_write_common_ops;
1198 * Create an RPC task for the given write request and kick it.
1199 * The page must have been locked by the caller.
1201 * It may happen that the page we're passed is not marked dirty.
1202 * This is the case if nfs_updatepage detects a conflicting request
1203 * that has been written but not committed.
1205 static int nfs_flush_one(struct nfs_pageio_descriptor *desc,
1206 struct nfs_pgio_header *hdr)
1208 struct nfs_page *req;
1209 struct page **pages;
1210 struct nfs_write_data *data;
1211 struct list_head *head = &desc->pg_list;
1212 struct nfs_commit_info cinfo;
1214 data = nfs_writedata_alloc(hdr, nfs_page_array_len(desc->pg_base,
1217 nfs_flush_error(desc, hdr);
1221 nfs_init_cinfo(&cinfo, desc->pg_inode, desc->pg_dreq);
1222 pages = data->pages.pagevec;
1223 while (!list_empty(head)) {
1224 req = nfs_list_entry(head->next);
1225 nfs_list_remove_request(req);
1226 nfs_list_add_request(req, &hdr->pages);
1227 *pages++ = req->wb_page;
1230 if ((desc->pg_ioflags & FLUSH_COND_STABLE) &&
1231 (desc->pg_moreio || nfs_reqs_to_commit(&cinfo)))
1232 desc->pg_ioflags &= ~FLUSH_COND_STABLE;
1234 /* Set up the argument struct */
1235 nfs_write_rpcsetup(data, desc->pg_count, 0, desc->pg_ioflags, &cinfo);
1236 list_add(&data->list, &hdr->rpc_list);
1237 desc->pg_rpc_callops = &nfs_write_common_ops;
1241 int nfs_generic_flush(struct nfs_pageio_descriptor *desc,
1242 struct nfs_pgio_header *hdr)
1244 if (desc->pg_bsize < PAGE_CACHE_SIZE)
1245 return nfs_flush_multi(desc, hdr);
1246 return nfs_flush_one(desc, hdr);
1248 EXPORT_SYMBOL_GPL(nfs_generic_flush);
1250 static int nfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
1252 struct nfs_write_header *whdr;
1253 struct nfs_pgio_header *hdr;
1256 whdr = nfs_writehdr_alloc();
1258 desc->pg_completion_ops->error_cleanup(&desc->pg_list);
1261 hdr = &whdr->header;
1262 nfs_pgheader_init(desc, hdr, nfs_writehdr_free);
1263 atomic_inc(&hdr->refcnt);
1264 ret = nfs_generic_flush(desc, hdr);
1266 ret = nfs_do_multiple_writes(&hdr->rpc_list,
1267 desc->pg_rpc_callops,
1269 if (atomic_dec_and_test(&hdr->refcnt))
1270 hdr->completion_ops->completion(hdr);
1274 static const struct nfs_pageio_ops nfs_pageio_write_ops = {
1275 .pg_test = nfs_generic_pg_test,
1276 .pg_doio = nfs_generic_pg_writepages,
1279 void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
1280 struct inode *inode, int ioflags,
1281 const struct nfs_pgio_completion_ops *compl_ops)
1283 nfs_pageio_init(pgio, inode, &nfs_pageio_write_ops, compl_ops,
1284 NFS_SERVER(inode)->wsize, ioflags);
1286 EXPORT_SYMBOL_GPL(nfs_pageio_init_write);
1288 void nfs_pageio_reset_write_mds(struct nfs_pageio_descriptor *pgio)
1290 pgio->pg_ops = &nfs_pageio_write_ops;
1291 pgio->pg_bsize = NFS_SERVER(pgio->pg_inode)->wsize;
1293 EXPORT_SYMBOL_GPL(nfs_pageio_reset_write_mds);
1296 void nfs_write_prepare(struct rpc_task *task, void *calldata)
1298 struct nfs_write_data *data = calldata;
1300 err = NFS_PROTO(data->header->inode)->write_rpc_prepare(task, data);
1302 rpc_exit(task, err);
1305 void nfs_commit_prepare(struct rpc_task *task, void *calldata)
1307 struct nfs_commit_data *data = calldata;
1309 NFS_PROTO(data->inode)->commit_rpc_prepare(task, data);
1313 * Handle a write reply that flushes a whole page.
1315 * FIXME: There is an inherent race with invalidate_inode_pages and
1316 * writebacks since the page->count is kept > 1 for as long
1317 * as the page has a write request pending.
1319 static void nfs_writeback_done_common(struct rpc_task *task, void *calldata)
1321 struct nfs_write_data *data = calldata;
1323 nfs_writeback_done(task, data);
1326 static void nfs_writeback_release_common(void *calldata)
1328 struct nfs_write_data *data = calldata;
1329 struct nfs_pgio_header *hdr = data->header;
1330 int status = data->task.tk_status;
1332 if ((status >= 0) && nfs_write_need_commit(data)) {
1333 spin_lock(&hdr->lock);
1334 if (test_bit(NFS_IOHDR_NEED_RESCHED, &hdr->flags))
1336 else if (!test_and_set_bit(NFS_IOHDR_NEED_COMMIT, &hdr->flags))
1337 memcpy(hdr->verf, &data->verf, sizeof(*hdr->verf));
1338 else if (memcmp(hdr->verf, &data->verf, sizeof(*hdr->verf)))
1339 set_bit(NFS_IOHDR_NEED_RESCHED, &hdr->flags);
1340 spin_unlock(&hdr->lock);
1342 nfs_writedata_release(data);
1345 static const struct rpc_call_ops nfs_write_common_ops = {
1346 .rpc_call_prepare = nfs_write_prepare,
1347 .rpc_call_done = nfs_writeback_done_common,
1348 .rpc_release = nfs_writeback_release_common,
1353 * This function is called when the WRITE call is complete.
1355 void nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data)
1357 struct nfs_writeargs *argp = &data->args;
1358 struct nfs_writeres *resp = &data->res;
1359 struct inode *inode = data->header->inode;
1362 dprintk("NFS: %5u nfs_writeback_done (status %d)\n",
1363 task->tk_pid, task->tk_status);
1366 * ->write_done will attempt to use post-op attributes to detect
1367 * conflicting writes by other clients. A strict interpretation
1368 * of close-to-open would allow us to continue caching even if
1369 * another writer had changed the file, but some applications
1370 * depend on tighter cache coherency when writing.
1372 status = NFS_PROTO(inode)->write_done(task, data);
1375 nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, resp->count);
1377 #if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
1378 if (resp->verf->committed < argp->stable && task->tk_status >= 0) {
1379 /* We tried a write call, but the server did not
1380 * commit data to stable storage even though we
1382 * Note: There is a known bug in Tru64 < 5.0 in which
1383 * the server reports NFS_DATA_SYNC, but performs
1384 * NFS_FILE_SYNC. We therefore implement this checking
1385 * as a dprintk() in order to avoid filling syslog.
1387 static unsigned long complain;
1389 /* Note this will print the MDS for a DS write */
1390 if (time_before(complain, jiffies)) {
1391 dprintk("NFS: faulty NFS server %s:"
1392 " (committed = %d) != (stable = %d)\n",
1393 NFS_SERVER(inode)->nfs_client->cl_hostname,
1394 resp->verf->committed, argp->stable);
1395 complain = jiffies + 300 * HZ;
1399 if (task->tk_status < 0)
1400 nfs_set_pgio_error(data->header, task->tk_status, argp->offset);
1401 else if (resp->count < argp->count) {
1402 static unsigned long complain;
1404 /* This a short write! */
1405 nfs_inc_stats(inode, NFSIOS_SHORTWRITE);
1407 /* Has the server at least made some progress? */
1408 if (resp->count == 0) {
1409 if (time_before(complain, jiffies)) {
1411 "NFS: Server wrote zero bytes, expected %u.\n",
1413 complain = jiffies + 300 * HZ;
1415 nfs_set_pgio_error(data->header, -EIO, argp->offset);
1416 task->tk_status = -EIO;
1419 /* Was this an NFSv2 write or an NFSv3 stable write? */
1420 if (resp->verf->committed != NFS_UNSTABLE) {
1421 /* Resend from where the server left off */
1422 data->mds_offset += resp->count;
1423 argp->offset += resp->count;
1424 argp->pgbase += resp->count;
1425 argp->count -= resp->count;
1427 /* Resend as a stable write in order to avoid
1428 * headaches in the case of a server crash.
1430 argp->stable = NFS_FILE_SYNC;
1432 rpc_restart_call_prepare(task);
1437 #if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
1438 static int nfs_commit_set_lock(struct nfs_inode *nfsi, int may_wait)
1442 if (!test_and_set_bit(NFS_INO_COMMIT, &nfsi->flags))
1446 ret = out_of_line_wait_on_bit_lock(&nfsi->flags,
1448 nfs_wait_bit_killable,
1450 return (ret < 0) ? ret : 1;
1453 static void nfs_commit_clear_lock(struct nfs_inode *nfsi)
1455 clear_bit(NFS_INO_COMMIT, &nfsi->flags);
1456 smp_mb__after_clear_bit();
1457 wake_up_bit(&nfsi->flags, NFS_INO_COMMIT);
1460 void nfs_commitdata_release(struct nfs_commit_data *data)
1462 put_nfs_open_context(data->context);
1463 nfs_commit_free(data);
1465 EXPORT_SYMBOL_GPL(nfs_commitdata_release);
1467 int nfs_initiate_commit(struct rpc_clnt *clnt, struct nfs_commit_data *data,
1468 const struct rpc_call_ops *call_ops,
1471 struct rpc_task *task;
1472 int priority = flush_task_priority(how);
1473 struct rpc_message msg = {
1474 .rpc_argp = &data->args,
1475 .rpc_resp = &data->res,
1476 .rpc_cred = data->cred,
1478 struct rpc_task_setup task_setup_data = {
1479 .task = &data->task,
1481 .rpc_message = &msg,
1482 .callback_ops = call_ops,
1483 .callback_data = data,
1484 .workqueue = nfsiod_workqueue,
1485 .flags = RPC_TASK_ASYNC | flags,
1486 .priority = priority,
1488 /* Set up the initial task struct. */
1489 NFS_PROTO(data->inode)->commit_setup(data, &msg);
1491 dprintk("NFS: %5u initiated commit call\n", data->task.tk_pid);
1493 nfs4_state_protect(NFS_SERVER(data->inode)->nfs_client,
1494 NFS_SP4_MACH_CRED_COMMIT, &task_setup_data.rpc_client, &msg);
1496 task = rpc_run_task(&task_setup_data);
1498 return PTR_ERR(task);
1499 if (how & FLUSH_SYNC)
1500 rpc_wait_for_completion_task(task);
1504 EXPORT_SYMBOL_GPL(nfs_initiate_commit);
1507 * Set up the argument/result storage required for the RPC call.
1509 void nfs_init_commit(struct nfs_commit_data *data,
1510 struct list_head *head,
1511 struct pnfs_layout_segment *lseg,
1512 struct nfs_commit_info *cinfo)
1514 struct nfs_page *first = nfs_list_entry(head->next);
1515 struct inode *inode = first->wb_context->dentry->d_inode;
1517 /* Set up the RPC argument and reply structs
1518 * NB: take care not to mess about with data->commit et al. */
1520 list_splice_init(head, &data->pages);
1522 data->inode = inode;
1523 data->cred = first->wb_context->cred;
1524 data->lseg = lseg; /* reference transferred */
1525 data->mds_ops = &nfs_commit_ops;
1526 data->completion_ops = cinfo->completion_ops;
1527 data->dreq = cinfo->dreq;
1529 data->args.fh = NFS_FH(data->inode);
1530 /* Note: we always request a commit of the entire inode */
1531 data->args.offset = 0;
1532 data->args.count = 0;
1533 data->context = get_nfs_open_context(first->wb_context);
1534 data->res.fattr = &data->fattr;
1535 data->res.verf = &data->verf;
1536 nfs_fattr_init(&data->fattr);
1538 EXPORT_SYMBOL_GPL(nfs_init_commit);
1540 void nfs_retry_commit(struct list_head *page_list,
1541 struct pnfs_layout_segment *lseg,
1542 struct nfs_commit_info *cinfo)
1544 struct nfs_page *req;
1546 while (!list_empty(page_list)) {
1547 req = nfs_list_entry(page_list->next);
1548 nfs_list_remove_request(req);
1549 nfs_mark_request_commit(req, lseg, cinfo);
1551 dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
1552 dec_bdi_stat(page_file_mapping(req->wb_page)->backing_dev_info,
1555 nfs_unlock_and_release_request(req);
1558 EXPORT_SYMBOL_GPL(nfs_retry_commit);
1561 * Commit dirty pages
1564 nfs_commit_list(struct inode *inode, struct list_head *head, int how,
1565 struct nfs_commit_info *cinfo)
1567 struct nfs_commit_data *data;
1569 data = nfs_commitdata_alloc();
1574 /* Set up the argument struct */
1575 nfs_init_commit(data, head, NULL, cinfo);
1576 atomic_inc(&cinfo->mds->rpcs_out);
1577 return nfs_initiate_commit(NFS_CLIENT(inode), data, data->mds_ops,
1580 nfs_retry_commit(head, NULL, cinfo);
1581 cinfo->completion_ops->error_cleanup(NFS_I(inode));
1586 * COMMIT call returned
1588 static void nfs_commit_done(struct rpc_task *task, void *calldata)
1590 struct nfs_commit_data *data = calldata;
1592 dprintk("NFS: %5u nfs_commit_done (status %d)\n",
1593 task->tk_pid, task->tk_status);
1595 /* Call the NFS version-specific code */
1596 NFS_PROTO(data->inode)->commit_done(task, data);
1599 static void nfs_commit_release_pages(struct nfs_commit_data *data)
1601 struct nfs_page *req;
1602 int status = data->task.tk_status;
1603 struct nfs_commit_info cinfo;
1605 while (!list_empty(&data->pages)) {
1606 req = nfs_list_entry(data->pages.next);
1607 nfs_list_remove_request(req);
1608 nfs_clear_page_commit(req->wb_page);
1610 dprintk("NFS: commit (%s/%llu %d@%lld)",
1611 req->wb_context->dentry->d_sb->s_id,
1612 (unsigned long long)NFS_FILEID(req->wb_context->dentry->d_inode),
1614 (long long)req_offset(req));
1616 nfs_context_set_write_error(req->wb_context, status);
1617 nfs_inode_remove_request(req);
1618 dprintk(", error = %d\n", status);
1622 /* Okay, COMMIT succeeded, apparently. Check the verifier
1623 * returned by the server against all stored verfs. */
1624 if (!memcmp(&req->wb_verf, &data->verf.verifier, sizeof(req->wb_verf))) {
1625 /* We have a match */
1626 nfs_inode_remove_request(req);
1630 /* We have a mismatch. Write the page again */
1631 dprintk(" mismatch\n");
1632 nfs_mark_request_dirty(req);
1633 set_bit(NFS_CONTEXT_RESEND_WRITES, &req->wb_context->flags);
1635 nfs_unlock_and_release_request(req);
1637 nfs_init_cinfo(&cinfo, data->inode, data->dreq);
1638 if (atomic_dec_and_test(&cinfo.mds->rpcs_out))
1639 nfs_commit_clear_lock(NFS_I(data->inode));
1642 static void nfs_commit_release(void *calldata)
1644 struct nfs_commit_data *data = calldata;
1646 data->completion_ops->completion(data);
1647 nfs_commitdata_release(calldata);
1650 static const struct rpc_call_ops nfs_commit_ops = {
1651 .rpc_call_prepare = nfs_commit_prepare,
1652 .rpc_call_done = nfs_commit_done,
1653 .rpc_release = nfs_commit_release,
1656 static const struct nfs_commit_completion_ops nfs_commit_completion_ops = {
1657 .completion = nfs_commit_release_pages,
1658 .error_cleanup = nfs_commit_clear_lock,
1661 int nfs_generic_commit_list(struct inode *inode, struct list_head *head,
1662 int how, struct nfs_commit_info *cinfo)
1666 status = pnfs_commit_list(inode, head, how, cinfo);
1667 if (status == PNFS_NOT_ATTEMPTED)
1668 status = nfs_commit_list(inode, head, how, cinfo);
1672 int nfs_commit_inode(struct inode *inode, int how)
1675 struct nfs_commit_info cinfo;
1676 int may_wait = how & FLUSH_SYNC;
1679 res = nfs_commit_set_lock(NFS_I(inode), may_wait);
1681 goto out_mark_dirty;
1682 nfs_init_cinfo_from_inode(&cinfo, inode);
1683 res = nfs_scan_commit(inode, &head, &cinfo);
1687 error = nfs_generic_commit_list(inode, &head, how, &cinfo);
1691 goto out_mark_dirty;
1692 error = wait_on_bit(&NFS_I(inode)->flags,
1694 nfs_wait_bit_killable,
1699 nfs_commit_clear_lock(NFS_I(inode));
1701 /* Note: If we exit without ensuring that the commit is complete,
1702 * we must mark the inode as dirty. Otherwise, future calls to
1703 * sync_inode() with the WB_SYNC_ALL flag set will fail to ensure
1704 * that the data is on the disk.
1707 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
1711 static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc)
1713 struct nfs_inode *nfsi = NFS_I(inode);
1714 int flags = FLUSH_SYNC;
1717 /* no commits means nothing needs to be done */
1718 if (!nfsi->commit_info.ncommit)
1721 if (wbc->sync_mode == WB_SYNC_NONE) {
1722 /* Don't commit yet if this is a non-blocking flush and there
1723 * are a lot of outstanding writes for this mapping.
1725 if (nfsi->commit_info.ncommit <= (nfsi->npages >> 1))
1726 goto out_mark_dirty;
1728 /* don't wait for the COMMIT response */
1732 ret = nfs_commit_inode(inode, flags);
1734 if (wbc->sync_mode == WB_SYNC_NONE) {
1735 if (ret < wbc->nr_to_write)
1736 wbc->nr_to_write -= ret;
1738 wbc->nr_to_write = 0;
1743 __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
1747 static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_control *wbc)
1753 int nfs_write_inode(struct inode *inode, struct writeback_control *wbc)
1755 return nfs_commit_unstable_pages(inode, wbc);
1757 EXPORT_SYMBOL_GPL(nfs_write_inode);
1760 * flush the inode to disk.
1762 int nfs_wb_all(struct inode *inode)
1764 struct writeback_control wbc = {
1765 .sync_mode = WB_SYNC_ALL,
1766 .nr_to_write = LONG_MAX,
1768 .range_end = LLONG_MAX,
1772 trace_nfs_writeback_inode_enter(inode);
1774 ret = sync_inode(inode, &wbc);
1776 trace_nfs_writeback_inode_exit(inode, ret);
1779 EXPORT_SYMBOL_GPL(nfs_wb_all);
1781 int nfs_wb_page_cancel(struct inode *inode, struct page *page)
1783 struct nfs_page *req;
1787 wait_on_page_writeback(page);
1788 req = nfs_page_find_request(page);
1791 if (nfs_lock_request(req)) {
1792 nfs_clear_request_commit(req);
1793 nfs_inode_remove_request(req);
1795 * In case nfs_inode_remove_request has marked the
1796 * page as being dirty
1798 cancel_dirty_page(page, PAGE_CACHE_SIZE);
1799 nfs_unlock_and_release_request(req);
1802 ret = nfs_wait_on_request(req);
1803 nfs_release_request(req);
1811 * Write back all requests on one page - we do this before reading it.
1813 int nfs_wb_page(struct inode *inode, struct page *page)
1815 loff_t range_start = page_file_offset(page);
1816 loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1);
1817 struct writeback_control wbc = {
1818 .sync_mode = WB_SYNC_ALL,
1820 .range_start = range_start,
1821 .range_end = range_end,
1825 trace_nfs_writeback_page_enter(inode);
1828 wait_on_page_writeback(page);
1829 if (clear_page_dirty_for_io(page)) {
1830 ret = nfs_writepage_locked(page, &wbc);
1836 if (!PagePrivate(page))
1838 ret = nfs_commit_inode(inode, FLUSH_SYNC);
1843 trace_nfs_writeback_page_exit(inode, ret);
1847 #ifdef CONFIG_MIGRATION
1848 int nfs_migrate_page(struct address_space *mapping, struct page *newpage,
1849 struct page *page, enum migrate_mode mode)
1852 * If PagePrivate is set, then the page is currently associated with
1853 * an in-progress read or write request. Don't try to migrate it.
1855 * FIXME: we could do this in principle, but we'll need a way to ensure
1856 * that we can safely release the inode reference while holding
1859 if (PagePrivate(page))
1862 if (!nfs_fscache_release_page(page, GFP_KERNEL))
1865 return migrate_page(mapping, newpage, page, mode);
1869 int __init nfs_init_writepagecache(void)
1871 nfs_wdata_cachep = kmem_cache_create("nfs_write_data",
1872 sizeof(struct nfs_write_header),
1873 0, SLAB_HWCACHE_ALIGN,
1875 if (nfs_wdata_cachep == NULL)
1878 nfs_wdata_mempool = mempool_create_slab_pool(MIN_POOL_WRITE,
1880 if (nfs_wdata_mempool == NULL)
1881 goto out_destroy_write_cache;
1883 nfs_cdata_cachep = kmem_cache_create("nfs_commit_data",
1884 sizeof(struct nfs_commit_data),
1885 0, SLAB_HWCACHE_ALIGN,
1887 if (nfs_cdata_cachep == NULL)
1888 goto out_destroy_write_mempool;
1890 nfs_commit_mempool = mempool_create_slab_pool(MIN_POOL_COMMIT,
1892 if (nfs_commit_mempool == NULL)
1893 goto out_destroy_commit_cache;
1896 * NFS congestion size, scale with available memory.
1908 * This allows larger machines to have larger/more transfers.
1909 * Limit the default to 256M
1911 nfs_congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
1912 if (nfs_congestion_kb > 256*1024)
1913 nfs_congestion_kb = 256*1024;
1917 out_destroy_commit_cache:
1918 kmem_cache_destroy(nfs_cdata_cachep);
1919 out_destroy_write_mempool:
1920 mempool_destroy(nfs_wdata_mempool);
1921 out_destroy_write_cache:
1922 kmem_cache_destroy(nfs_wdata_cachep);
1926 void nfs_destroy_writepagecache(void)
1928 mempool_destroy(nfs_commit_mempool);
1929 kmem_cache_destroy(nfs_cdata_cachep);
1930 mempool_destroy(nfs_wdata_mempool);
1931 kmem_cache_destroy(nfs_wdata_cachep);