1/*
2 *  linux/fs/ext3/file.c
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 *  from
10 *
11 *  linux/fs/minix/file.c
12 *
13 *  Copyright (C) 1991, 1992  Linus Torvalds
14 *
15 *  ext3 fs regular file handling primitives
16 *
17 *  64-bit file support on 64-bit platforms by Jakub Jelinek
18 *	(jj@sunsite.ms.mff.cuni.cz)
19 */
20
21#include <linux/time.h>
22#include <linux/fs.h>
23#include <linux/jbd.h>
24#include <linux/ext3_fs.h>
25#include <linux/ext3_jbd.h>
26#include "xattr.h"
27#include "acl.h"
28
29/*
30 * Called when an inode is released. Note that this is different
31 * from ext3_file_open: open gets called at every open, but release
32 * gets called only when /all/ the files are closed.
33 */
34static int ext3_release_file (struct inode * inode, struct file * filp)
35{
36	/* if we are the last writer on the inode, drop the block reservation */
37	if ((filp->f_mode & FMODE_WRITE) &&
38			(atomic_read(&inode->i_writecount) == 1))
39	{
40		mutex_lock(&EXT3_I(inode)->truncate_mutex);
41		ext3_discard_reservation(inode);
42		mutex_unlock(&EXT3_I(inode)->truncate_mutex);
43	}
44	if (is_dx(inode) && filp->private_data)
45		ext3_htree_free_dir_info(filp->private_data);
46
47	return 0;
48}
49
50static ssize_t
51ext3_file_write(struct kiocb *iocb, const struct iovec *iov,
52		unsigned long nr_segs, loff_t pos)
53{
54	struct file *file = iocb->ki_filp;
55	struct inode *inode = file->f_path.dentry->d_inode;
56	ssize_t ret;
57	int err;
58
59	ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
60
61	/*
62	 * Skip flushing if there was an error, or if nothing was written.
63	 */
64	if (ret <= 0)
65		return ret;
66
67	/*
68	 * If the inode is IS_SYNC, or is O_SYNC and we are doing data
69	 * journalling then we need to make sure that we force the transaction
70	 * to disk to keep all metadata uptodate synchronously.
71	 */
72	if (file->f_flags & O_SYNC) {
73		/*
74		 * If we are non-data-journaled, then the dirty data has
75		 * already been flushed to backing store by generic_osync_inode,
76		 * and the inode has been flushed too if there have been any
77		 * modifications other than mere timestamp updates.
78		 *
79		 * Open question --- do we care about flushing timestamps too
80		 * if the inode is IS_SYNC?
81		 */
82		if (!ext3_should_journal_data(inode))
83			return ret;
84
85		goto force_commit;
86	}
87
88	/*
89	 * So we know that there has been no forced data flush.  If the inode
90	 * is marked IS_SYNC, we need to force one ourselves.
91	 */
92	if (!IS_SYNC(inode))
93		return ret;
94
95	/*
96	 * Open question #2 --- should we force data to disk here too?  If we
97	 * don't, the only impact is that data=writeback filesystems won't
98	 * flush data to disk automatically on IS_SYNC, only metadata (but
99	 * historically, that is what ext2 has done.)
100	 */
101
102force_commit:
103	err = ext3_force_commit(inode->i_sb);
104	if (err)
105		return err;
106	return ret;
107}
108
109const struct file_operations ext3_file_operations = {
110	.llseek		= generic_file_llseek,
111	.read		= do_sync_read,
112	.write		= do_sync_write,
113	.aio_read	= generic_file_aio_read,
114	.aio_write	= ext3_file_write,
115	.ioctl		= ext3_ioctl,
116#ifdef CONFIG_COMPAT
117	.compat_ioctl	= ext3_compat_ioctl,
118#endif
119	.mmap		= generic_file_mmap,
120	.open		= generic_file_open,
121	.release	= ext3_release_file,
122	.fsync		= ext3_sync_file,
123	.sendfile	= generic_file_sendfile,
124	.splice_read	= generic_file_splice_read,
125	.splice_write	= generic_file_splice_write,
126};
127
128const struct inode_operations ext3_file_inode_operations = {
129	.truncate	= ext3_truncate,
130	.setattr	= ext3_setattr,
131#ifdef CONFIG_EXT3_FS_XATTR
132	.setxattr	= generic_setxattr,
133	.getxattr	= generic_getxattr,
134	.listxattr	= ext3_listxattr,
135	.removexattr	= generic_removexattr,
136#endif
137	.permission	= ext3_permission,
138};
139