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- // SPDX-License-Identifier: GPL-2.0-only
- /*
- * linux/fs/nfs/file.c
- *
- * Copyright (C) 1992 Rick Sladkey
- *
- * Changes Copyright (C) 1994 by Florian La Roche
- * - Do not copy data too often around in the kernel.
- * - In nfs_file_read the return value of kmalloc wasn't checked.
- * - Put in a better version of read look-ahead buffering. Original idea
- * and implementation by Wai S Kok [email protected].
- *
- * Expire cache on write to a file by Wai S Kok (Oct 1994).
- *
- * Total rewrite of read side for new NFS buffer cache.. Linus.
- *
- * nfs regular file handling functions
- */
- #include <linux/module.h>
- #include <linux/time.h>
- #include <linux/kernel.h>
- #include <linux/errno.h>
- #include <linux/fcntl.h>
- #include <linux/stat.h>
- #include <linux/nfs_fs.h>
- #include <linux/nfs_mount.h>
- #include <linux/mm.h>
- #include <linux/pagemap.h>
- #include <linux/gfp.h>
- #include <linux/swap.h>
- #include <linux/uaccess.h>
- #include "delegation.h"
- #include "internal.h"
- #include "iostat.h"
- #include "fscache.h"
- #include "pnfs.h"
- #include "nfstrace.h"
- #define NFSDBG_FACILITY NFSDBG_FILE
- static const struct vm_operations_struct nfs_file_vm_ops;
- int nfs_check_flags(int flags)
- {
- if ((flags & (O_APPEND | O_DIRECT)) == (O_APPEND | O_DIRECT))
- return -EINVAL;
- return 0;
- }
- EXPORT_SYMBOL_GPL(nfs_check_flags);
- /*
- * Open file
- */
- static int
- nfs_file_open(struct inode *inode, struct file *filp)
- {
- int res;
- dprintk("NFS: open file(%pD2)\n", filp);
- nfs_inc_stats(inode, NFSIOS_VFSOPEN);
- res = nfs_check_flags(filp->f_flags);
- if (res)
- return res;
- res = nfs_open(inode, filp);
- if (res == 0)
- filp->f_mode |= FMODE_CAN_ODIRECT;
- return res;
- }
- int
- nfs_file_release(struct inode *inode, struct file *filp)
- {
- dprintk("NFS: release(%pD2)\n", filp);
- nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
- nfs_file_clear_open_context(filp);
- nfs_fscache_release_file(inode, filp);
- return 0;
- }
- EXPORT_SYMBOL_GPL(nfs_file_release);
- /**
- * nfs_revalidate_file_size - Revalidate the file size
- * @inode: pointer to inode struct
- * @filp: pointer to struct file
- *
- * Revalidates the file length. This is basically a wrapper around
- * nfs_revalidate_inode() that takes into account the fact that we may
- * have cached writes (in which case we don't care about the server's
- * idea of what the file length is), or O_DIRECT (in which case we
- * shouldn't trust the cache).
- */
- static int nfs_revalidate_file_size(struct inode *inode, struct file *filp)
- {
- struct nfs_server *server = NFS_SERVER(inode);
- if (filp->f_flags & O_DIRECT)
- goto force_reval;
- if (nfs_check_cache_invalid(inode, NFS_INO_INVALID_SIZE))
- goto force_reval;
- return 0;
- force_reval:
- return __nfs_revalidate_inode(server, inode);
- }
- loff_t nfs_file_llseek(struct file *filp, loff_t offset, int whence)
- {
- dprintk("NFS: llseek file(%pD2, %lld, %d)\n",
- filp, offset, whence);
- /*
- * whence == SEEK_END || SEEK_DATA || SEEK_HOLE => we must revalidate
- * the cached file length
- */
- if (whence != SEEK_SET && whence != SEEK_CUR) {
- struct inode *inode = filp->f_mapping->host;
- int retval = nfs_revalidate_file_size(inode, filp);
- if (retval < 0)
- return (loff_t)retval;
- }
- return generic_file_llseek(filp, offset, whence);
- }
- EXPORT_SYMBOL_GPL(nfs_file_llseek);
- /*
- * Flush all dirty pages, and check for write errors.
- */
- static int
- nfs_file_flush(struct file *file, fl_owner_t id)
- {
- struct inode *inode = file_inode(file);
- errseq_t since;
- dprintk("NFS: flush(%pD2)\n", file);
- nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
- if ((file->f_mode & FMODE_WRITE) == 0)
- return 0;
- /* Flush writes to the server and return any errors */
- since = filemap_sample_wb_err(file->f_mapping);
- nfs_wb_all(inode);
- return filemap_check_wb_err(file->f_mapping, since);
- }
- ssize_t
- nfs_file_read(struct kiocb *iocb, struct iov_iter *to)
- {
- struct inode *inode = file_inode(iocb->ki_filp);
- ssize_t result;
- if (iocb->ki_flags & IOCB_DIRECT)
- return nfs_file_direct_read(iocb, to, false);
- dprintk("NFS: read(%pD2, %zu@%lu)\n",
- iocb->ki_filp,
- iov_iter_count(to), (unsigned long) iocb->ki_pos);
- nfs_start_io_read(inode);
- result = nfs_revalidate_mapping(inode, iocb->ki_filp->f_mapping);
- if (!result) {
- result = generic_file_read_iter(iocb, to);
- if (result > 0)
- nfs_add_stats(inode, NFSIOS_NORMALREADBYTES, result);
- }
- nfs_end_io_read(inode);
- return result;
- }
- EXPORT_SYMBOL_GPL(nfs_file_read);
- int
- nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
- {
- struct inode *inode = file_inode(file);
- int status;
- dprintk("NFS: mmap(%pD2)\n", file);
- /* Note: generic_file_mmap() returns ENOSYS on nommu systems
- * so we call that before revalidating the mapping
- */
- status = generic_file_mmap(file, vma);
- if (!status) {
- vma->vm_ops = &nfs_file_vm_ops;
- status = nfs_revalidate_mapping(inode, file->f_mapping);
- }
- return status;
- }
- EXPORT_SYMBOL_GPL(nfs_file_mmap);
- /*
- * Flush any dirty pages for this process, and check for write errors.
- * The return status from this call provides a reliable indication of
- * whether any write errors occurred for this process.
- */
- static int
- nfs_file_fsync_commit(struct file *file, int datasync)
- {
- struct inode *inode = file_inode(file);
- int ret, ret2;
- dprintk("NFS: fsync file(%pD2) datasync %d\n", file, datasync);
- nfs_inc_stats(inode, NFSIOS_VFSFSYNC);
- ret = nfs_commit_inode(inode, FLUSH_SYNC);
- ret2 = file_check_and_advance_wb_err(file);
- if (ret2 < 0)
- return ret2;
- return ret;
- }
- int
- nfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
- {
- struct inode *inode = file_inode(file);
- struct nfs_inode *nfsi = NFS_I(inode);
- long save_nredirtied = atomic_long_read(&nfsi->redirtied_pages);
- long nredirtied;
- int ret;
- trace_nfs_fsync_enter(inode);
- for (;;) {
- ret = file_write_and_wait_range(file, start, end);
- if (ret != 0)
- break;
- ret = nfs_file_fsync_commit(file, datasync);
- if (ret != 0)
- break;
- ret = pnfs_sync_inode(inode, !!datasync);
- if (ret != 0)
- break;
- nredirtied = atomic_long_read(&nfsi->redirtied_pages);
- if (nredirtied == save_nredirtied)
- break;
- save_nredirtied = nredirtied;
- }
- trace_nfs_fsync_exit(inode, ret);
- return ret;
- }
- EXPORT_SYMBOL_GPL(nfs_file_fsync);
- /*
- * Decide whether a read/modify/write cycle may be more efficient
- * then a modify/write/read cycle when writing to a page in the
- * page cache.
- *
- * Some pNFS layout drivers can only read/write at a certain block
- * granularity like all block devices and therefore we must perform
- * read/modify/write whenever a page hasn't read yet and the data
- * to be written there is not aligned to a block boundary and/or
- * smaller than the block size.
- *
- * The modify/write/read cycle may occur if a page is read before
- * being completely filled by the writer. In this situation, the
- * page must be completely written to stable storage on the server
- * before it can be refilled by reading in the page from the server.
- * This can lead to expensive, small, FILE_SYNC mode writes being
- * done.
- *
- * It may be more efficient to read the page first if the file is
- * open for reading in addition to writing, the page is not marked
- * as Uptodate, it is not dirty or waiting to be committed,
- * indicating that it was previously allocated and then modified,
- * that there were valid bytes of data in that range of the file,
- * and that the new data won't completely replace the old data in
- * that range of the file.
- */
- static bool nfs_full_page_write(struct page *page, loff_t pos, unsigned int len)
- {
- unsigned int pglen = nfs_page_length(page);
- unsigned int offset = pos & (PAGE_SIZE - 1);
- unsigned int end = offset + len;
- return !pglen || (end >= pglen && !offset);
- }
- static bool nfs_want_read_modify_write(struct file *file, struct page *page,
- loff_t pos, unsigned int len)
- {
- /*
- * Up-to-date pages, those with ongoing or full-page write
- * don't need read/modify/write
- */
- if (PageUptodate(page) || PagePrivate(page) ||
- nfs_full_page_write(page, pos, len))
- return false;
- if (pnfs_ld_read_whole_page(file->f_mapping->host))
- return true;
- /* Open for reading too? */
- if (file->f_mode & FMODE_READ)
- return true;
- return false;
- }
- /*
- * This does the "real" work of the write. We must allocate and lock the
- * page to be sent back to the generic routine, which then copies the
- * data from user space.
- *
- * If the writer ends up delaying the write, the writer needs to
- * increment the page use counts until he is done with the page.
- */
- static int nfs_write_begin(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len,
- struct page **pagep, void **fsdata)
- {
- int ret;
- pgoff_t index = pos >> PAGE_SHIFT;
- struct page *page;
- int once_thru = 0;
- dfprintk(PAGECACHE, "NFS: write_begin(%pD2(%lu), %u@%lld)\n",
- file, mapping->host->i_ino, len, (long long) pos);
- start:
- page = grab_cache_page_write_begin(mapping, index);
- if (!page)
- return -ENOMEM;
- *pagep = page;
- ret = nfs_flush_incompatible(file, page);
- if (ret) {
- unlock_page(page);
- put_page(page);
- } else if (!once_thru &&
- nfs_want_read_modify_write(file, page, pos, len)) {
- once_thru = 1;
- ret = nfs_read_folio(file, page_folio(page));
- put_page(page);
- if (!ret)
- goto start;
- }
- return ret;
- }
- static int nfs_write_end(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned copied,
- struct page *page, void *fsdata)
- {
- unsigned offset = pos & (PAGE_SIZE - 1);
- struct nfs_open_context *ctx = nfs_file_open_context(file);
- int status;
- dfprintk(PAGECACHE, "NFS: write_end(%pD2(%lu), %u@%lld)\n",
- file, mapping->host->i_ino, len, (long long) pos);
- /*
- * Zero any uninitialised parts of the page, and then mark the page
- * as up to date if it turns out that we're extending the file.
- */
- if (!PageUptodate(page)) {
- unsigned pglen = nfs_page_length(page);
- unsigned end = offset + copied;
- if (pglen == 0) {
- zero_user_segments(page, 0, offset,
- end, PAGE_SIZE);
- SetPageUptodate(page);
- } else if (end >= pglen) {
- zero_user_segment(page, end, PAGE_SIZE);
- if (offset == 0)
- SetPageUptodate(page);
- } else
- zero_user_segment(page, pglen, PAGE_SIZE);
- }
- status = nfs_updatepage(file, page, offset, copied);
- unlock_page(page);
- put_page(page);
- if (status < 0)
- return status;
- NFS_I(mapping->host)->write_io += copied;
- if (nfs_ctx_key_to_expire(ctx, mapping->host))
- nfs_wb_all(mapping->host);
- return copied;
- }
- /*
- * Partially or wholly invalidate a page
- * - Release the private state associated with a page if undergoing complete
- * page invalidation
- * - Called if either PG_private or PG_fscache is set on the page
- * - Caller holds page lock
- */
- static void nfs_invalidate_folio(struct folio *folio, size_t offset,
- size_t length)
- {
- dfprintk(PAGECACHE, "NFS: invalidate_folio(%lu, %zu, %zu)\n",
- folio->index, offset, length);
- if (offset != 0 || length < folio_size(folio))
- return;
- /* Cancel any unstarted writes on this page */
- nfs_wb_folio_cancel(folio->mapping->host, folio);
- folio_wait_fscache(folio);
- }
- /*
- * Attempt to release the private state associated with a folio
- * - Called if either private or fscache flags are set on the folio
- * - Caller holds folio lock
- * - Return true (may release folio) or false (may not)
- */
- static bool nfs_release_folio(struct folio *folio, gfp_t gfp)
- {
- dfprintk(PAGECACHE, "NFS: release_folio(%p)\n", folio);
- /* If the private flag is set, then the folio is not freeable */
- if (folio_test_private(folio))
- return false;
- return nfs_fscache_release_folio(folio, gfp);
- }
- static void nfs_check_dirty_writeback(struct folio *folio,
- bool *dirty, bool *writeback)
- {
- struct nfs_inode *nfsi;
- struct address_space *mapping = folio->mapping;
- /*
- * Check if an unstable folio is currently being committed and
- * if so, have the VM treat it as if the folio is under writeback
- * so it will not block due to folios that will shortly be freeable.
- */
- nfsi = NFS_I(mapping->host);
- if (atomic_read(&nfsi->commit_info.rpcs_out)) {
- *writeback = true;
- return;
- }
- /*
- * If the private flag is set, then the folio is not freeable
- * and as the inode is not being committed, it's not going to
- * be cleaned in the near future so treat it as dirty
- */
- if (folio_test_private(folio))
- *dirty = true;
- }
- /*
- * Attempt to clear the private state associated with a page when an error
- * occurs that requires the cached contents of an inode to be written back or
- * destroyed
- * - Called if either PG_private or fscache is set on the page
- * - Caller holds page lock
- * - Return 0 if successful, -error otherwise
- */
- static int nfs_launder_folio(struct folio *folio)
- {
- struct inode *inode = folio->mapping->host;
- dfprintk(PAGECACHE, "NFS: launder_folio(%ld, %llu)\n",
- inode->i_ino, folio_pos(folio));
- folio_wait_fscache(folio);
- return nfs_wb_page(inode, &folio->page);
- }
- static int nfs_swap_activate(struct swap_info_struct *sis, struct file *file,
- sector_t *span)
- {
- unsigned long blocks;
- long long isize;
- int ret;
- struct inode *inode = file_inode(file);
- struct rpc_clnt *clnt = NFS_CLIENT(inode);
- struct nfs_client *cl = NFS_SERVER(inode)->nfs_client;
- spin_lock(&inode->i_lock);
- blocks = inode->i_blocks;
- isize = inode->i_size;
- spin_unlock(&inode->i_lock);
- if (blocks*512 < isize) {
- pr_warn("swap activate: swapfile has holes\n");
- return -EINVAL;
- }
- ret = rpc_clnt_swap_activate(clnt);
- if (ret)
- return ret;
- ret = add_swap_extent(sis, 0, sis->max, 0);
- if (ret < 0) {
- rpc_clnt_swap_deactivate(clnt);
- return ret;
- }
- *span = sis->pages;
- if (cl->rpc_ops->enable_swap)
- cl->rpc_ops->enable_swap(inode);
- sis->flags |= SWP_FS_OPS;
- return ret;
- }
- static void nfs_swap_deactivate(struct file *file)
- {
- struct inode *inode = file_inode(file);
- struct rpc_clnt *clnt = NFS_CLIENT(inode);
- struct nfs_client *cl = NFS_SERVER(inode)->nfs_client;
- rpc_clnt_swap_deactivate(clnt);
- if (cl->rpc_ops->disable_swap)
- cl->rpc_ops->disable_swap(file_inode(file));
- }
- const struct address_space_operations nfs_file_aops = {
- .read_folio = nfs_read_folio,
- .readahead = nfs_readahead,
- .dirty_folio = filemap_dirty_folio,
- .writepage = nfs_writepage,
- .writepages = nfs_writepages,
- .write_begin = nfs_write_begin,
- .write_end = nfs_write_end,
- .invalidate_folio = nfs_invalidate_folio,
- .release_folio = nfs_release_folio,
- .migrate_folio = nfs_migrate_folio,
- .launder_folio = nfs_launder_folio,
- .is_dirty_writeback = nfs_check_dirty_writeback,
- .error_remove_page = generic_error_remove_page,
- .swap_activate = nfs_swap_activate,
- .swap_deactivate = nfs_swap_deactivate,
- .swap_rw = nfs_swap_rw,
- };
- /*
- * Notification that a PTE pointing to an NFS page is about to be made
- * writable, implying that someone is about to modify the page through a
- * shared-writable mapping
- */
- static vm_fault_t nfs_vm_page_mkwrite(struct vm_fault *vmf)
- {
- struct page *page = vmf->page;
- struct file *filp = vmf->vma->vm_file;
- struct inode *inode = file_inode(filp);
- unsigned pagelen;
- vm_fault_t ret = VM_FAULT_NOPAGE;
- struct address_space *mapping;
- dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%pD2(%lu), offset %lld)\n",
- filp, filp->f_mapping->host->i_ino,
- (long long)page_offset(page));
- sb_start_pagefault(inode->i_sb);
- /* make sure the cache has finished storing the page */
- if (PageFsCache(page) &&
- wait_on_page_fscache_killable(vmf->page) < 0) {
- ret = VM_FAULT_RETRY;
- goto out;
- }
- wait_on_bit_action(&NFS_I(inode)->flags, NFS_INO_INVALIDATING,
- nfs_wait_bit_killable,
- TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
- lock_page(page);
- mapping = page_file_mapping(page);
- if (mapping != inode->i_mapping)
- goto out_unlock;
- wait_on_page_writeback(page);
- pagelen = nfs_page_length(page);
- if (pagelen == 0)
- goto out_unlock;
- ret = VM_FAULT_LOCKED;
- if (nfs_flush_incompatible(filp, page) == 0 &&
- nfs_updatepage(filp, page, 0, pagelen) == 0)
- goto out;
- ret = VM_FAULT_SIGBUS;
- out_unlock:
- unlock_page(page);
- out:
- sb_end_pagefault(inode->i_sb);
- return ret;
- }
- static const struct vm_operations_struct nfs_file_vm_ops = {
- .fault = filemap_fault,
- .map_pages = filemap_map_pages,
- .page_mkwrite = nfs_vm_page_mkwrite,
- };
- ssize_t nfs_file_write(struct kiocb *iocb, struct iov_iter *from)
- {
- struct file *file = iocb->ki_filp;
- struct inode *inode = file_inode(file);
- unsigned int mntflags = NFS_SERVER(inode)->flags;
- ssize_t result, written;
- errseq_t since;
- int error;
- result = nfs_key_timeout_notify(file, inode);
- if (result)
- return result;
- if (iocb->ki_flags & IOCB_DIRECT)
- return nfs_file_direct_write(iocb, from, false);
- dprintk("NFS: write(%pD2, %zu@%Ld)\n",
- file, iov_iter_count(from), (long long) iocb->ki_pos);
- if (IS_SWAPFILE(inode))
- goto out_swapfile;
- /*
- * O_APPEND implies that we must revalidate the file length.
- */
- if (iocb->ki_flags & IOCB_APPEND || iocb->ki_pos > i_size_read(inode)) {
- result = nfs_revalidate_file_size(inode, file);
- if (result)
- return result;
- }
- nfs_clear_invalid_mapping(file->f_mapping);
- since = filemap_sample_wb_err(file->f_mapping);
- nfs_start_io_write(inode);
- result = generic_write_checks(iocb, from);
- if (result > 0) {
- current->backing_dev_info = inode_to_bdi(inode);
- result = generic_perform_write(iocb, from);
- current->backing_dev_info = NULL;
- }
- nfs_end_io_write(inode);
- if (result <= 0)
- goto out;
- written = result;
- iocb->ki_pos += written;
- nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written);
- if (mntflags & NFS_MOUNT_WRITE_EAGER) {
- result = filemap_fdatawrite_range(file->f_mapping,
- iocb->ki_pos - written,
- iocb->ki_pos - 1);
- if (result < 0)
- goto out;
- }
- if (mntflags & NFS_MOUNT_WRITE_WAIT) {
- filemap_fdatawait_range(file->f_mapping,
- iocb->ki_pos - written,
- iocb->ki_pos - 1);
- }
- result = generic_write_sync(iocb, written);
- if (result < 0)
- return result;
- out:
- /* Return error values */
- error = filemap_check_wb_err(file->f_mapping, since);
- switch (error) {
- default:
- break;
- case -EDQUOT:
- case -EFBIG:
- case -ENOSPC:
- nfs_wb_all(inode);
- error = file_check_and_advance_wb_err(file);
- if (error < 0)
- result = error;
- }
- return result;
- out_swapfile:
- printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
- return -ETXTBSY;
- }
- EXPORT_SYMBOL_GPL(nfs_file_write);
- static int
- do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
- {
- struct inode *inode = filp->f_mapping->host;
- int status = 0;
- unsigned int saved_type = fl->fl_type;
- /* Try local locking first */
- posix_test_lock(filp, fl);
- if (fl->fl_type != F_UNLCK) {
- /* found a conflict */
- goto out;
- }
- fl->fl_type = saved_type;
- if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
- goto out_noconflict;
- if (is_local)
- goto out_noconflict;
- status = NFS_PROTO(inode)->lock(filp, cmd, fl);
- out:
- return status;
- out_noconflict:
- fl->fl_type = F_UNLCK;
- goto out;
- }
- static int
- do_unlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
- {
- struct inode *inode = filp->f_mapping->host;
- struct nfs_lock_context *l_ctx;
- int status;
- /*
- * Flush all pending writes before doing anything
- * with locks..
- */
- nfs_wb_all(inode);
- l_ctx = nfs_get_lock_context(nfs_file_open_context(filp));
- if (!IS_ERR(l_ctx)) {
- status = nfs_iocounter_wait(l_ctx);
- nfs_put_lock_context(l_ctx);
- /* NOTE: special case
- * If we're signalled while cleaning up locks on process exit, we
- * still need to complete the unlock.
- */
- if (status < 0 && !(fl->fl_flags & FL_CLOSE))
- return status;
- }
- /*
- * Use local locking if mounted with "-onolock" or with appropriate
- * "-olocal_lock="
- */
- if (!is_local)
- status = NFS_PROTO(inode)->lock(filp, cmd, fl);
- else
- status = locks_lock_file_wait(filp, fl);
- return status;
- }
- static int
- do_setlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
- {
- struct inode *inode = filp->f_mapping->host;
- int status;
- /*
- * Flush all pending writes before doing anything
- * with locks..
- */
- status = nfs_sync_mapping(filp->f_mapping);
- if (status != 0)
- goto out;
- /*
- * Use local locking if mounted with "-onolock" or with appropriate
- * "-olocal_lock="
- */
- if (!is_local)
- status = NFS_PROTO(inode)->lock(filp, cmd, fl);
- else
- status = locks_lock_file_wait(filp, fl);
- if (status < 0)
- goto out;
- /*
- * Invalidate cache to prevent missing any changes. If
- * the file is mapped, clear the page cache as well so
- * those mappings will be loaded.
- *
- * This makes locking act as a cache coherency point.
- */
- nfs_sync_mapping(filp->f_mapping);
- if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_READ)) {
- nfs_zap_caches(inode);
- if (mapping_mapped(filp->f_mapping))
- nfs_revalidate_mapping(inode, filp->f_mapping);
- }
- out:
- return status;
- }
- /*
- * Lock a (portion of) a file
- */
- int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
- {
- struct inode *inode = filp->f_mapping->host;
- int ret = -ENOLCK;
- int is_local = 0;
- dprintk("NFS: lock(%pD2, t=%x, fl=%x, r=%lld:%lld)\n",
- filp, fl->fl_type, fl->fl_flags,
- (long long)fl->fl_start, (long long)fl->fl_end);
- nfs_inc_stats(inode, NFSIOS_VFSLOCK);
- if (fl->fl_flags & FL_RECLAIM)
- return -ENOGRACE;
- if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FCNTL)
- is_local = 1;
- if (NFS_PROTO(inode)->lock_check_bounds != NULL) {
- ret = NFS_PROTO(inode)->lock_check_bounds(fl);
- if (ret < 0)
- goto out_err;
- }
- if (IS_GETLK(cmd))
- ret = do_getlk(filp, cmd, fl, is_local);
- else if (fl->fl_type == F_UNLCK)
- ret = do_unlk(filp, cmd, fl, is_local);
- else
- ret = do_setlk(filp, cmd, fl, is_local);
- out_err:
- return ret;
- }
- EXPORT_SYMBOL_GPL(nfs_lock);
- /*
- * Lock a (portion of) a file
- */
- int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
- {
- struct inode *inode = filp->f_mapping->host;
- int is_local = 0;
- dprintk("NFS: flock(%pD2, t=%x, fl=%x)\n",
- filp, fl->fl_type, fl->fl_flags);
- if (!(fl->fl_flags & FL_FLOCK))
- return -ENOLCK;
- if (NFS_SERVER(inode)->flags & NFS_MOUNT_LOCAL_FLOCK)
- is_local = 1;
- /* We're simulating flock() locks using posix locks on the server */
- if (fl->fl_type == F_UNLCK)
- return do_unlk(filp, cmd, fl, is_local);
- return do_setlk(filp, cmd, fl, is_local);
- }
- EXPORT_SYMBOL_GPL(nfs_flock);
- const struct file_operations nfs_file_operations = {
- .llseek = nfs_file_llseek,
- .read_iter = nfs_file_read,
- .write_iter = nfs_file_write,
- .mmap = nfs_file_mmap,
- .open = nfs_file_open,
- .flush = nfs_file_flush,
- .release = nfs_file_release,
- .fsync = nfs_file_fsync,
- .lock = nfs_lock,
- .flock = nfs_flock,
- .splice_read = generic_file_splice_read,
- .splice_write = iter_file_splice_write,
- .check_flags = nfs_check_flags,
- .setlease = simple_nosetlease,
- };
- EXPORT_SYMBOL_GPL(nfs_file_operations);
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