1/*
2 * QNX4 file system, Linux implementation.
3 *
4 * Version : 0.1
5 *
6 * Using parts of the xiafs filesystem.
7 *
8 * History :
9 *
10 * 24-03-1998 by Richard Frowijn : first release.
11 */
12
13#include <linux/errno.h>
14#include <linux/time.h>
15#include <linux/stat.h>
16#include <linux/fcntl.h>
17#include <linux/smp_lock.h>
18#include <linux/buffer_head.h>
19
20#include <linux/fs.h>
21#include <linux/qnx4_fs.h>
22
23#include <asm/system.h>
24
25/*
26 * The functions for qnx4 fs file synchronization.
27 */
28
29#ifdef CONFIG_QNX4FS_RW
30
31static int sync_block(struct inode *inode, unsigned short *block, int wait)
32{
33	struct buffer_head *bh;
34	unsigned short tmp;
35
36	if (!*block)
37		return 0;
38	tmp = *block;
39	bh = sb_find_get_block(inode->i_sb, *block);
40	if (!bh)
41		return 0;
42	if (*block != tmp) {
43		brelse(bh);
44		return 1;
45	}
46	if (wait && buffer_req(bh) && !buffer_uptodate(bh)) {
47		brelse(bh);
48		return -1;
49	}
50	if (wait || !buffer_uptodate(bh) || !buffer_dirty(bh)) {
51		brelse(bh);
52		return 0;
53	}
54	ll_rw_block(WRITE, 1, &bh);
55	atomic_dec(&bh->b_count);
56	return 0;
57}
58
59#ifdef WTF
60static int sync_iblock(struct inode *inode, unsigned short *iblock,
61		       struct buffer_head **bh, int wait)
62{
63	int rc;
64	unsigned short tmp;
65
66	*bh = NULL;
67	tmp = *iblock;
68	if (!tmp)
69		return 0;
70	rc = sync_block(inode, iblock, wait);
71	if (rc)
72		return rc;
73	*bh = sb_bread(inode->i_sb, tmp);
74	if (tmp != *iblock) {
75		brelse(*bh);
76		*bh = NULL;
77		return 1;
78	}
79	if (!*bh)
80		return -1;
81	return 0;
82}
83#endif
84
85static int sync_direct(struct inode *inode, int wait)
86{
87	int i;
88	int rc, err = 0;
89
90	for (i = 0; i < 7; i++) {
91		rc = sync_block(inode,
92				(unsigned short *) qnx4_raw_inode(inode)->di_first_xtnt.xtnt_blk + i, wait);
93		if (rc > 0)
94			break;
95		if (rc)
96			err = rc;
97	}
98	return err;
99}
100
101#ifdef WTF
102static int sync_indirect(struct inode *inode, unsigned short *iblock, int wait)
103{
104	int i;
105	struct buffer_head *ind_bh;
106	int rc, err = 0;
107
108	rc = sync_iblock(inode, iblock, &ind_bh, wait);
109	if (rc || !ind_bh)
110		return rc;
111
112	for (i = 0; i < 512; i++) {
113		rc = sync_block(inode,
114				((unsigned short *) ind_bh->b_data) + i,
115				wait);
116		if (rc > 0)
117			break;
118		if (rc)
119			err = rc;
120	}
121	brelse(ind_bh);
122	return err;
123}
124
125static int sync_dindirect(struct inode *inode, unsigned short *diblock,
126			  int wait)
127{
128	int i;
129	struct buffer_head *dind_bh;
130	int rc, err = 0;
131
132	rc = sync_iblock(inode, diblock, &dind_bh, wait);
133	if (rc || !dind_bh)
134		return rc;
135
136	for (i = 0; i < 512; i++) {
137		rc = sync_indirect(inode,
138				((unsigned short *) dind_bh->b_data) + i,
139				   wait);
140		if (rc > 0)
141			break;
142		if (rc)
143			err = rc;
144	}
145	brelse(dind_bh);
146	return err;
147}
148#endif
149
150int qnx4_sync_file(struct file *file, struct dentry *dentry, int unused)
151{
152        struct inode *inode = dentry->d_inode;
153	int wait, err = 0;
154
155        (void) file;
156	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
157	      S_ISLNK(inode->i_mode)))
158		return -EINVAL;
159
160	lock_kernel();
161	for (wait = 0; wait <= 1; wait++) {
162		err |= sync_direct(inode, wait);
163	}
164	err |= qnx4_sync_inode(inode);
165	unlock_kernel();
166	return (err < 0) ? -EIO : 0;
167}
168
169#endif
170