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/config.h>
14 #include <linux/errno.h>
15 #include <linux/sched.h>
16 #include <linux/stat.h>
17 #include <linux/fcntl.h>
18 #include <linux/locks.h>
19 #include <linux/smp_lock.h>
20
21 #include <linux/fs.h>
22 #include <linux/qnx4_fs.h>
23
24 #include <asm/segment.h>
25 #include <asm/system.h>
26
27 /*
28 * The functions for qnx4 fs file synchronization.
29 */
30
31 #ifdef CONFIG_QNX4FS_RW
32
sync_block(struct inode * inode,unsigned short * block,int wait)33 static int sync_block(struct inode *inode, unsigned short *block, int wait)
34 {
35 struct buffer_head *bh;
36 unsigned short tmp;
37
38 if (!*block)
39 return 0;
40 tmp = *block;
41 bh = sb_get_hash_table(inode->i_sb, *block);
42 if (!bh)
43 return 0;
44 if (*block != tmp) {
45 brelse(bh);
46 return 1;
47 }
48 if (wait && buffer_req(bh) && !buffer_uptodate(bh)) {
49 brelse(bh);
50 return -1;
51 }
52 if (wait || !buffer_uptodate(bh) || !buffer_dirty(bh)) {
53 brelse(bh);
54 return 0;
55 }
56 ll_rw_block(WRITE, 1, &bh);
57 atomic_dec(&bh->b_count);
58 return 0;
59 }
60
61 #ifdef WTF
sync_iblock(struct inode * inode,unsigned short * iblock,struct buffer_head ** bh,int wait)62 static int sync_iblock(struct inode *inode, unsigned short *iblock,
63 struct buffer_head **bh, int wait)
64 {
65 int rc;
66 unsigned short tmp;
67
68 *bh = NULL;
69 tmp = *iblock;
70 if (!tmp)
71 return 0;
72 rc = sync_block(inode, iblock, wait);
73 if (rc)
74 return rc;
75 *bh = sb_bread(inode->i_sb, tmp);
76 if (tmp != *iblock) {
77 brelse(*bh);
78 *bh = NULL;
79 return 1;
80 }
81 if (!*bh)
82 return -1;
83 return 0;
84 }
85 #endif
86
sync_direct(struct inode * inode,int wait)87 static int sync_direct(struct inode *inode, int wait)
88 {
89 int i;
90 int rc, err = 0;
91
92 for (i = 0; i < 7; i++) {
93 rc = sync_block(inode,
94 (unsigned short *) inode->u.qnx4_i.i_first_xtnt.xtnt_blk + i, wait);
95 if (rc > 0)
96 break;
97 if (rc)
98 err = rc;
99 }
100 return err;
101 }
102
103 #ifdef WTF
sync_indirect(struct inode * inode,unsigned short * iblock,int wait)104 static int sync_indirect(struct inode *inode, unsigned short *iblock, int wait)
105 {
106 int i;
107 struct buffer_head *ind_bh;
108 int rc, err = 0;
109
110 rc = sync_iblock(inode, iblock, &ind_bh, wait);
111 if (rc || !ind_bh)
112 return rc;
113
114 for (i = 0; i < 512; i++) {
115 rc = sync_block(inode,
116 ((unsigned short *) ind_bh->b_data) + i,
117 wait);
118 if (rc > 0)
119 break;
120 if (rc)
121 err = rc;
122 }
123 brelse(ind_bh);
124 return err;
125 }
126
sync_dindirect(struct inode * inode,unsigned short * diblock,int wait)127 static int sync_dindirect(struct inode *inode, unsigned short *diblock,
128 int wait)
129 {
130 int i;
131 struct buffer_head *dind_bh;
132 int rc, err = 0;
133
134 rc = sync_iblock(inode, diblock, &dind_bh, wait);
135 if (rc || !dind_bh)
136 return rc;
137
138 for (i = 0; i < 512; i++) {
139 rc = sync_indirect(inode,
140 ((unsigned short *) dind_bh->b_data) + i,
141 wait);
142 if (rc > 0)
143 break;
144 if (rc)
145 err = rc;
146 }
147 brelse(dind_bh);
148 return err;
149 }
150 #endif
151
qnx4_sync_file(struct file * file,struct dentry * dentry,int unused)152 int qnx4_sync_file(struct file *file, struct dentry *dentry, int unused)
153 {
154 struct inode *inode = dentry->d_inode;
155 int wait, err = 0;
156
157 (void) file;
158 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
159 S_ISLNK(inode->i_mode)))
160 return -EINVAL;
161
162 lock_kernel();
163 for (wait = 0; wait <= 1; wait++) {
164 err |= sync_direct(inode, wait);
165 }
166 err |= qnx4_sync_inode(inode);
167 unlock_kernel();
168 return (err < 0) ? -EIO : 0;
169 }
170
171 #endif
172