4 * Copyright (C) 1992 Rick Sladkey
6 * Changes Copyright (C) 1994 by Florian La Roche
7 * - Do not copy data too often around in the kernel.
8 * - In nfs_file_read the return value of kmalloc wasn't checked.
9 * - Put in a better version of read look-ahead buffering. Original idea
10 * and implementation by Wai S Kok elekokws@ee.nus.sg.
12 * Expire cache on write to a file by Wai S Kok (Oct 1994).
14 * Total rewrite of read side for new NFS buffer cache.. Linus.
16 * nfs regular file handling functions
19 #include <linux/module.h>
20 #include <linux/time.h>
21 #include <linux/kernel.h>
22 #include <linux/errno.h>
23 #include <linux/fcntl.h>
24 #include <linux/stat.h>
25 #include <linux/nfs_fs.h>
26 #include <linux/nfs_mount.h>
28 #include <linux/pagemap.h>
29 #include <linux/aio.h>
30 #include <linux/gfp.h>
31 #include <linux/swap.h>
33 #include <asm/uaccess.h>
35 #include "delegation.h"
43 #define NFSDBG_FACILITY NFSDBG_FILE
45 static const struct vm_operations_struct nfs_file_vm_ops;
47 /* Hack for future NFS swap support */
49 # define IS_SWAPFILE(inode) (0)
52 int nfs_check_flags(int flags)
54 if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT))
59 EXPORT_SYMBOL_GPL(nfs_check_flags);
65 nfs_file_open(struct inode *inode, struct file *filp)
69 dprintk("NFS: open file(%pD2)\n", filp);
71 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
72 res = nfs_check_flags(filp->f_flags);
76 res = nfs_open(inode, filp);
81 nfs_file_release(struct inode *inode, struct file *filp)
83 dprintk("NFS: release(%pD2)\n", filp);
85 nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
86 return nfs_release(inode, filp);
88 EXPORT_SYMBOL_GPL(nfs_file_release);
91 * nfs_revalidate_size - Revalidate the file size
92 * @inode - pointer to inode struct
93 * @file - pointer to struct file
95 * Revalidates the file length. This is basically a wrapper around
96 * nfs_revalidate_inode() that takes into account the fact that we may
97 * have cached writes (in which case we don't care about the server's
98 * idea of what the file length is), or O_DIRECT (in which case we
99 * shouldn't trust the cache).
101 static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
103 struct nfs_server *server = NFS_SERVER(inode);
104 struct nfs_inode *nfsi = NFS_I(inode);
106 if (nfs_have_delegated_attributes(inode))
109 if (filp->f_flags & O_DIRECT)
111 if (nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE)
113 if (nfs_attribute_timeout(inode))
118 return __nfs_revalidate_inode(server, inode);
121 loff_t nfs_file_llseek(struct file *filp, loff_t offset, int whence)
123 dprintk("NFS: llseek file(%pD2, %lld, %d)\n",
124 filp, offset, whence);
127 * whence == SEEK_END || SEEK_DATA || SEEK_HOLE => we must revalidate
128 * the cached file length
130 if (whence != SEEK_SET && whence != SEEK_CUR) {
131 struct inode *inode = filp->f_mapping->host;
133 int retval = nfs_revalidate_file_size(inode, filp);
135 return (loff_t)retval;
138 return generic_file_llseek(filp, offset, whence);
140 EXPORT_SYMBOL_GPL(nfs_file_llseek);
143 * Flush all dirty pages, and check for write errors.
146 nfs_file_flush(struct file *file, fl_owner_t id)
148 struct inode *inode = file_inode(file);
150 dprintk("NFS: flush(%pD2)\n", file);
152 nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
153 if ((file->f_mode & FMODE_WRITE) == 0)
157 * If we're holding a write delegation, then just start the i/o
158 * but don't wait for completion (or send a commit).
160 if (NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE))
161 return filemap_fdatawrite(file->f_mapping);
163 /* Flush writes to the server and return any errors */
164 return vfs_fsync(file, 0);
166 EXPORT_SYMBOL_GPL(nfs_file_flush);
169 nfs_file_read(struct kiocb *iocb, struct iov_iter *to)
171 struct inode *inode = file_inode(iocb->ki_filp);
174 if (iocb->ki_filp->f_flags & O_DIRECT)
175 return nfs_file_direct_read(iocb, to, iocb->ki_pos, true);
177 dprintk("NFS: read(%pD2, %zu@%lu)\n",
179 iov_iter_count(to), (unsigned long) iocb->ki_pos);
181 result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
183 result = generic_file_read_iter(iocb, to);
185 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, result);
189 EXPORT_SYMBOL_GPL(nfs_file_read);
192 nfs_file_splice_read(struct file *filp, loff_t *ppos,
193 struct pipe_inode_info *pipe, size_t count,
196 struct inode *inode = file_inode(filp);
199 dprintk("NFS: splice_read(%pD2, %lu@%Lu)\n",
200 filp, (unsigned long) count, (unsigned long long) *ppos);
202 res = nfs_revalidate_mapping(inode, filp->f_mapping);
204 res = generic_file_splice_read(filp, ppos, pipe, count, flags);
206 nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, res);
210 EXPORT_SYMBOL_GPL(nfs_file_splice_read);
213 nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
215 struct inode *inode = file_inode(file);
218 dprintk("NFS: mmap(%pD2)\n", file);
220 /* Note: generic_file_mmap() returns ENOSYS on nommu systems
221 * so we call that before revalidating the mapping
223 status = generic_file_mmap(file, vma);
225 vma->vm_ops = &nfs_file_vm_ops;
226 status = nfs_revalidate_mapping(inode, file->f_mapping);
230 EXPORT_SYMBOL_GPL(nfs_file_mmap);
233 * Flush any dirty pages for this process, and check for write errors.
234 * The return status from this call provides a reliable indication of
235 * whether any write errors occurred for this process.
237 * Notice that it clears the NFS_CONTEXT_ERROR_WRITE before synching to
238 * disk, but it retrieves and clears ctx->error after synching, despite
239 * the two being set at the same time in nfs_context_set_write_error().
240 * This is because the former is used to notify the _next_ call to
241 * nfs_file_write() that a write error occurred, and hence cause it to
242 * fall back to doing a synchronous write.
245 nfs_file_fsync_commit(struct file *file, loff_t start, loff_t end, int datasync)
247 struct nfs_open_context *ctx = nfs_file_open_context(file);
248 struct inode *inode = file_inode(file);
249 int have_error, do_resend, status;
252 dprintk("NFS: fsync file(%pD2) datasync %d\n", file, datasync);
254 nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
255 do_resend = test_and_clear_bit(NFS_CONTEXT_RESEND_WRITES, &ctx->flags);
256 have_error = test_and_clear_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
257 status = nfs_commit_inode(inode, FLUSH_SYNC);
258 have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
260 ret = xchg(&ctx->error, 0);
268 do_resend |= test_bit(NFS_CONTEXT_RESEND_WRITES, &ctx->flags);
274 EXPORT_SYMBOL_GPL(nfs_file_fsync_commit);
277 nfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
280 struct inode *inode = file_inode(file);
282 trace_nfs_fsync_enter(inode);
285 ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
288 mutex_lock(&inode->i_mutex);
289 ret = nfs_file_fsync_commit(file, start, end, datasync);
290 mutex_unlock(&inode->i_mutex);
292 * If nfs_file_fsync_commit detected a server reboot, then
293 * resend all dirty pages that might have been covered by
294 * the NFS_CONTEXT_RESEND_WRITES flag
298 } while (ret == -EAGAIN);
300 trace_nfs_fsync_exit(inode, ret);
305 * Decide whether a read/modify/write cycle may be more efficient
306 * then a modify/write/read cycle when writing to a page in the
309 * The modify/write/read cycle may occur if a page is read before
310 * being completely filled by the writer. In this situation, the
311 * page must be completely written to stable storage on the server
312 * before it can be refilled by reading in the page from the server.
313 * This can lead to expensive, small, FILE_SYNC mode writes being
316 * It may be more efficient to read the page first if the file is
317 * open for reading in addition to writing, the page is not marked
318 * as Uptodate, it is not dirty or waiting to be committed,
319 * indicating that it was previously allocated and then modified,
320 * that there were valid bytes of data in that range of the file,
321 * and that the new data won't completely replace the old data in
322 * that range of the file.
324 static int nfs_want_read_modify_write(struct file *file, struct page *page,
325 loff_t pos, unsigned len)
327 unsigned int pglen = nfs_page_length(page);
328 unsigned int offset = pos & (PAGE_CACHE_SIZE - 1);
329 unsigned int end = offset + len;
331 if (pnfs_ld_read_whole_page(file->f_mapping->host)) {
332 if (!PageUptodate(page))
337 if ((file->f_mode & FMODE_READ) && /* open for read? */
338 !PageUptodate(page) && /* Uptodate? */
339 !PagePrivate(page) && /* i/o request already? */
340 pglen && /* valid bytes of file? */
341 (end < pglen || offset)) /* replace all valid bytes? */
347 * This does the "real" work of the write. We must allocate and lock the
348 * page to be sent back to the generic routine, which then copies the
349 * data from user space.
351 * If the writer ends up delaying the write, the writer needs to
352 * increment the page use counts until he is done with the page.
354 static int nfs_write_begin(struct file *file, struct address_space *mapping,
355 loff_t pos, unsigned len, unsigned flags,
356 struct page **pagep, void **fsdata)
359 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
363 dfprintk(PAGECACHE, "NFS: write_begin(%pD2(%lu), %u@%lld)\n",
364 file, mapping->host->i_ino, len, (long long) pos);
368 * Prevent starvation issues if someone is doing a consistency
371 ret = wait_on_bit_action(&NFS_I(mapping->host)->flags, NFS_INO_FLUSHING,
372 nfs_wait_bit_killable, TASK_KILLABLE);
376 page = grab_cache_page_write_begin(mapping, index, flags);
381 ret = nfs_flush_incompatible(file, page);
384 page_cache_release(page);
385 } else if (!once_thru &&
386 nfs_want_read_modify_write(file, page, pos, len)) {
388 ret = nfs_readpage(file, page);
389 page_cache_release(page);
396 static int nfs_write_end(struct file *file, struct address_space *mapping,
397 loff_t pos, unsigned len, unsigned copied,
398 struct page *page, void *fsdata)
400 unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
401 struct nfs_open_context *ctx = nfs_file_open_context(file);
404 dfprintk(PAGECACHE, "NFS: write_end(%pD2(%lu), %u@%lld)\n",
405 file, mapping->host->i_ino, len, (long long) pos);
408 * Zero any uninitialised parts of the page, and then mark the page
409 * as up to date if it turns out that we're extending the file.
411 if (!PageUptodate(page)) {
412 unsigned pglen = nfs_page_length(page);
413 unsigned end = offset + len;
416 zero_user_segments(page, 0, offset,
417 end, PAGE_CACHE_SIZE);
418 SetPageUptodate(page);
419 } else if (end >= pglen) {
420 zero_user_segment(page, end, PAGE_CACHE_SIZE);
422 SetPageUptodate(page);
424 zero_user_segment(page, pglen, PAGE_CACHE_SIZE);
427 status = nfs_updatepage(file, page, offset, copied);
430 page_cache_release(page);
434 NFS_I(mapping->host)->write_io += copied;
436 if (nfs_ctx_key_to_expire(ctx)) {
437 status = nfs_wb_all(mapping->host);
446 * Partially or wholly invalidate a page
447 * - Release the private state associated with a page if undergoing complete
449 * - Called if either PG_private or PG_fscache is set on the page
450 * - Caller holds page lock
452 static void nfs_invalidate_page(struct page *page, unsigned int offset,
455 dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %u, %u)\n",
456 page, offset, length);
458 if (offset != 0 || length < PAGE_CACHE_SIZE)
460 /* Cancel any unstarted writes on this page */
461 nfs_wb_page_cancel(page_file_mapping(page)->host, page);
463 nfs_fscache_invalidate_page(page, page->mapping->host);
467 * Attempt to release the private state associated with a page
468 * - Called if either PG_private or PG_fscache is set on the page
469 * - Caller holds page lock
470 * - Return true (may release page) or false (may not)
472 static int nfs_release_page(struct page *page, gfp_t gfp)
474 struct address_space *mapping = page->mapping;
476 dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page);
478 /* Only do I/O if gfp is a superset of GFP_KERNEL, and we're not
479 * doing this memory reclaim for a fs-related allocation.
481 if (mapping && (gfp & GFP_KERNEL) == GFP_KERNEL &&
482 !(current->flags & PF_FSTRANS)) {
483 int how = FLUSH_SYNC;
485 /* Don't let kswapd deadlock waiting for OOM RPC calls */
486 if (current_is_kswapd())
488 nfs_commit_inode(mapping->host, how);
490 /* If PagePrivate() is set, then the page is not freeable */
491 if (PagePrivate(page))
493 return nfs_fscache_release_page(page, gfp);
496 static void nfs_check_dirty_writeback(struct page *page,
497 bool *dirty, bool *writeback)
499 struct nfs_inode *nfsi;
500 struct address_space *mapping = page_file_mapping(page);
502 if (!mapping || PageSwapCache(page))
506 * Check if an unstable page is currently being committed and
507 * if so, have the VM treat it as if the page is under writeback
508 * so it will not block due to pages that will shortly be freeable.
510 nfsi = NFS_I(mapping->host);
511 if (test_bit(NFS_INO_COMMIT, &nfsi->flags)) {
517 * If PagePrivate() is set, then the page is not freeable and as the
518 * inode is not being committed, it's not going to be cleaned in the
519 * near future so treat it as dirty
521 if (PagePrivate(page))
526 * Attempt to clear the private state associated with a page when an error
527 * occurs that requires the cached contents of an inode to be written back or
529 * - Called if either PG_private or fscache is set on the page
530 * - Caller holds page lock
531 * - Return 0 if successful, -error otherwise
533 static int nfs_launder_page(struct page *page)
535 struct inode *inode = page_file_mapping(page)->host;
536 struct nfs_inode *nfsi = NFS_I(inode);
538 dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n",
539 inode->i_ino, (long long)page_offset(page));
541 nfs_fscache_wait_on_page_write(nfsi, page);
542 return nfs_wb_page(inode, page);
545 #ifdef CONFIG_NFS_SWAP
546 static int nfs_swap_activate(struct swap_info_struct *sis, struct file *file,
550 return xs_swapper(NFS_CLIENT(file->f_mapping->host)->cl_xprt, 1);
553 static void nfs_swap_deactivate(struct file *file)
555 xs_swapper(NFS_CLIENT(file->f_mapping->host)->cl_xprt, 0);
559 const struct address_space_operations nfs_file_aops = {
560 .readpage = nfs_readpage,
561 .readpages = nfs_readpages,
562 .set_page_dirty = __set_page_dirty_nobuffers,
563 .writepage = nfs_writepage,
564 .writepages = nfs_writepages,
565 .write_begin = nfs_write_begin,
566 .write_end = nfs_write_end,
567 .invalidatepage = nfs_invalidate_page,
568 .releasepage = nfs_release_page,
569 .direct_IO = nfs_direct_IO,
570 .migratepage = nfs_migrate_page,
571 .launder_page = nfs_launder_page,
572 .is_dirty_writeback = nfs_check_dirty_writeback,
573 .error_remove_page = generic_error_remove_page,
574 #ifdef CONFIG_NFS_SWAP
575 .swap_activate = nfs_swap_activate,
576 .swap_deactivate = nfs_swap_deactivate,
581 * Notification that a PTE pointing to an NFS page is about to be made
582 * writable, implying that someone is about to modify the page through a
583 * shared-writable mapping
585 static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
587 struct page *page = vmf->page;
588 struct file *filp = vma->vm_file;
589 struct inode *inode = file_inode(filp);
591 int ret = VM_FAULT_NOPAGE;
592 struct address_space *mapping;
594 dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%pD2(%lu), offset %lld)\n",
595 filp, filp->f_mapping->host->i_ino,
596 (long long)page_offset(page));
598 /* make sure the cache has finished storing the page */
599 nfs_fscache_wait_on_page_write(NFS_I(inode), page);
602 mapping = page_file_mapping(page);
603 if (mapping != inode->i_mapping)
606 wait_on_page_writeback(page);
608 pagelen = nfs_page_length(page);
612 ret = VM_FAULT_LOCKED;
613 if (nfs_flush_incompatible(filp, page) == 0 &&
614 nfs_updatepage(filp, page, 0, pagelen) == 0)
617 ret = VM_FAULT_SIGBUS;
624 static const struct vm_operations_struct nfs_file_vm_ops = {
625 .fault = filemap_fault,
626 .map_pages = filemap_map_pages,
627 .page_mkwrite = nfs_vm_page_mkwrite,
628 .remap_pages = generic_file_remap_pages,
631 static int nfs_need_sync_write(struct file *filp, struct inode *inode)
633 struct nfs_open_context *ctx;
635 if (IS_SYNC(inode) || (filp->f_flags & O_DSYNC))
637 ctx = nfs_file_open_context(filp);
638 if (test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags) ||
639 nfs_ctx_key_to_expire(ctx))
644 ssize_t nfs_file_write(struct kiocb *iocb, struct iov_iter *from)
646 struct file *file = iocb->ki_filp;
647 struct inode *inode = file_inode(file);
648 unsigned long written = 0;
650 size_t count = iov_iter_count(from);
651 loff_t pos = iocb->ki_pos;
653 result = nfs_key_timeout_notify(file, inode);
657 if (file->f_flags & O_DIRECT)
658 return nfs_file_direct_write(iocb, from, pos, true);
660 dprintk("NFS: write(%pD2, %zu@%Ld)\n",
661 file, count, (long long) pos);
664 if (IS_SWAPFILE(inode))
667 * O_APPEND implies that we must revalidate the file length.
669 if (file->f_flags & O_APPEND) {
670 result = nfs_revalidate_file_size(inode, file);
679 result = generic_file_write_iter(iocb, from);
683 /* Return error values for O_DSYNC and IS_SYNC() */
684 if (result >= 0 && nfs_need_sync_write(file, inode)) {
685 int err = vfs_fsync(file, 0);
690 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written);
695 printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
698 EXPORT_SYMBOL_GPL(nfs_file_write);
701 do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
703 struct inode *inode = filp->f_mapping->host;
705 unsigned int saved_type = fl->fl_type;
707 /* Try local locking first */
708 posix_test_lock(filp, fl);
709 if (fl->fl_type != F_UNLCK) {
710 /* found a conflict */
713 fl->fl_type = saved_type;
715 if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
721 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
725 fl->fl_type = F_UNLCK;
729 static int do_vfs_lock(struct file *file, struct file_lock *fl)
732 switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
734 res = posix_lock_file_wait(file, fl);
737 res = flock_lock_file_wait(file, fl);
746 do_unlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
748 struct inode *inode = filp->f_mapping->host;
749 struct nfs_lock_context *l_ctx;
753 * Flush all pending writes before doing anything
756 nfs_sync_mapping(filp->f_mapping);
758 l_ctx = nfs_get_lock_context(nfs_file_open_context(filp));
759 if (!IS_ERR(l_ctx)) {
760 status = nfs_iocounter_wait(&l_ctx->io_count);
761 nfs_put_lock_context(l_ctx);
766 /* NOTE: special case
767 * If we're signalled while cleaning up locks on process exit, we
768 * still need to complete the unlock.
771 * Use local locking if mounted with "-onolock" or with appropriate
775 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
777 status = do_vfs_lock(filp, fl);
782 is_time_granular(struct timespec *ts) {
783 return ((ts->tv_sec == 0) && (ts->tv_nsec <= 1000));
787 do_setlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
789 struct inode *inode = filp->f_mapping->host;
793 * Flush all pending writes before doing anything
796 status = nfs_sync_mapping(filp->f_mapping);
801 * Use local locking if mounted with "-onolock" or with appropriate
805 status = NFS_PROTO(inode)->lock(filp, cmd, fl);
807 status = do_vfs_lock(filp, fl);
812 * Revalidate the cache if the server has time stamps granular
813 * enough to detect subsecond changes. Otherwise, clear the
814 * cache to prevent missing any changes.
816 * This makes locking act as a cache coherency point.
818 nfs_sync_mapping(filp->f_mapping);
819 if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_READ)) {
820 if (is_time_granular(&NFS_SERVER(inode)->time_delta))
821 __nfs_revalidate_inode(NFS_SERVER(inode), inode);
823 nfs_zap_caches(inode);
830 * Lock a (portion of) a file
832 int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
834 struct inode *inode = filp->f_mapping->host;
838 dprintk("NFS: lock(%pD2, t=%x, fl=%x, r=%lld:%lld)\n",
839 filp, fl->fl_type, fl->fl_flags,
840 (long long)fl->fl_start, (long long)fl->fl_end);
842 nfs_inc_stats(inode, NFSIOS_VFSLOCK);
844 /* No mandatory locks over NFS */
845 if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
848 if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FCNTL)
851 if (NFS_PROTO(inode)->lock_check_bounds != NULL) {
852 ret = NFS_PROTO(inode)->lock_check_bounds(fl);
858 ret = do_getlk(filp, cmd, fl, is_local);
859 else if (fl->fl_type == F_UNLCK)
860 ret = do_unlk(filp, cmd, fl, is_local);
862 ret = do_setlk(filp, cmd, fl, is_local);
866 EXPORT_SYMBOL_GPL(nfs_lock);
869 * Lock a (portion of) a file
871 int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
873 struct inode *inode = filp->f_mapping->host;
876 dprintk("NFS: flock(%pD2, t=%x, fl=%x)\n",
877 filp, fl->fl_type, fl->fl_flags);
879 if (!(fl->fl_flags & FL_FLOCK))
883 * The NFSv4 protocol doesn't support LOCK_MAND, which is not part of
884 * any standard. In principle we might be able to support LOCK_MAND
885 * on NFSv2/3 since NLMv3/4 support DOS share modes, but for now the
886 * NFS code is not set up for it.
888 if (fl->fl_type & LOCK_MAND)
891 if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FLOCK)
894 /* We're simulating flock() locks using posix locks on the server */
895 if (fl->fl_type == F_UNLCK)
896 return do_unlk(filp, cmd, fl, is_local);
897 return do_setlk(filp, cmd, fl, is_local);
899 EXPORT_SYMBOL_GPL(nfs_flock);
902 * There is no protocol support for leases, so we have no way to implement
903 * them correctly in the face of opens by other clients.
905 int nfs_setlease(struct file *file, long arg, struct file_lock **fl)
907 dprintk("NFS: setlease(%pD2, arg=%ld)\n", file, arg);
910 EXPORT_SYMBOL_GPL(nfs_setlease);
912 const struct file_operations nfs_file_operations = {
913 .llseek = nfs_file_llseek,
914 .read = new_sync_read,
915 .write = new_sync_write,
916 .read_iter = nfs_file_read,
917 .write_iter = nfs_file_write,
918 .mmap = nfs_file_mmap,
919 .open = nfs_file_open,
920 .flush = nfs_file_flush,
921 .release = nfs_file_release,
922 .fsync = nfs_file_fsync,
925 .splice_read = nfs_file_splice_read,
926 .splice_write = iter_file_splice_write,
927 .check_flags = nfs_check_flags,
928 .setlease = nfs_setlease,
930 EXPORT_SYMBOL_GPL(nfs_file_operations);