2 * file.c - NTFS kernel file operations. Part of the Linux-NTFS project.
4 * Copyright (c) 2001-2004 Anton Altaparmakov
6 * This program/include file is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as published
8 * by the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program/include file is distributed in the hope that it will be
12 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
13 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program (in the main directory of the Linux-NTFS
18 * distribution in the file COPYING); if not, write to the Free Software
19 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 * ntfs_file_open - called when an inode is about to be opened
26 * @vi: inode to be opened
27 * @filp: file structure describing the inode
29 * Limit file size to the page cache limit on architectures where unsigned long
30 * is 32-bits. This is the most we can do for now without overflowing the page
31 * cache page index. Doing it this way means we don't run into problems because
32 * of existing too large files. It would be better to allow the user to read
33 * the beginning of the file but I doubt very much anyone is going to hit this
34 * check on a 32-bit architecture, so there is no point in adding the extra
35 * complexity required to support this.
37 * On 64-bit architectures, the check is hopefully optimized away by the
40 * After the check passes, just call generic_file_open() to do its work.
42 static int ntfs_file_open(struct inode *vi, struct file *filp)
44 if (sizeof(unsigned long) < 8) {
45 if (vi->i_size > MAX_LFS_FILESIZE)
48 return generic_file_open(vi, filp);
54 * ntfs_file_fsync - sync a file to disk
55 * @filp: file to be synced
56 * @dentry: dentry describing the file to sync
57 * @datasync: if non-zero only flush user data and not metadata
59 * Data integrity sync of a file to disk. Used for fsync, fdatasync, and msync
60 * system calls. This function is inspired by fs/buffer.c::file_fsync().
62 * If @datasync is false, write the mft record and all associated extent mft
63 * records as well as the $DATA attribute and then sync the block device.
65 * If @datasync is true and the attribute is non-resident, we skip the writing
66 * of the mft record and all associated extent mft records (this might still
67 * happen due to the write_inode_now() call).
69 * Also, if @datasync is true, we do not wait on the inode to be written out
70 * but we always wait on the page cache pages to be written out.
72 * Note: In the past @filp could be NULL so we ignore it as we don't need it
75 * Locking: Caller must hold i_sem on the inode.
77 * TODO: We should probably also write all attribute/index inodes associated
78 * with this inode but since we have no simple way of getting to them we ignore
79 * this problem for now.
81 static int ntfs_file_fsync(struct file *filp, struct dentry *dentry,
84 struct inode *vi = dentry->d_inode;
87 ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
88 BUG_ON(S_ISDIR(vi->i_mode));
89 if (!datasync || !NInoNonResident(NTFS_I(vi)))
90 ret = ntfs_write_inode(vi, 1);
91 write_inode_now(vi, !datasync);
92 err = sync_blockdev(vi->i_sb->s_bdev);
93 if (unlikely(err && !ret))
98 ntfs_warning(vi->i_sb, "Failed to f%ssync inode 0x%lx. Error "
99 "%u.", datasync ? "data" : "", vi->i_ino, -ret);
105 struct file_operations ntfs_file_ops = {
106 .llseek = generic_file_llseek, /* Seek inside file. */
107 .read = generic_file_read, /* Read from file. */
108 .aio_read = generic_file_aio_read, /* Async read from file. */
109 .readv = generic_file_readv, /* Read from file. */
111 .write = generic_file_write, /* Write to file. */
112 .aio_write = generic_file_aio_write, /* Async write to file. */
113 .writev = generic_file_writev, /* Write to file. */
114 /*.release = ,*/ /* Last file is closed. See
116 ext2_release_file() for
117 how to use this to discard
118 preallocated space for
119 write opened files. */
120 .fsync = ntfs_file_fsync, /* Sync a file to disk. */
121 /*.aio_fsync = ,*/ /* Sync all outstanding async
125 /*.ioctl = ,*/ /* Perform function on the
126 mounted filesystem. */
127 .mmap = generic_file_mmap, /* Mmap file. */
128 .open = ntfs_file_open, /* Open file. */
129 .sendfile = generic_file_sendfile, /* Zero-copy data send with
130 the data source being on
131 the ntfs partition. We
132 do not need to care about
133 the data destination. */
134 /*.sendpage = ,*/ /* Zero-copy data send with
135 the data destination being
136 on the ntfs partition. We
137 do not need to care about
141 struct inode_operations ntfs_file_inode_ops = {
143 .truncate = ntfs_truncate,
144 .setattr = ntfs_setattr,
148 struct file_operations ntfs_empty_file_ops = {};
150 struct inode_operations ntfs_empty_inode_ops = {};