1 /*
2 * linux/fs/sysv/fsync.c
3 *
4 * minix/fsync.c
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 * Copyright (C) 1993 Stephen Tweedie (sct@dcs.ed.ac.uk)
7 *
8 * coh/fsync.c
9 * Copyright (C) 1993 Pascal Haible, Bruno Haible
10 *
11 * sysv/fsync.c
12 * Copyright (C) 1993 Bruno Haible
13 *
14 * SystemV/Coherent fsync primitive
15 */
16
17 #include <linux/errno.h>
18 #include <linux/stat.h>
19 #include <linux/fs.h>
20 #include <linux/sysv_fs.h>
21 #include <linux/smp_lock.h>
22
23
24 /* return values: 0 means OK/done, 1 means redo, -1 means I/O error. */
25
26 /* Sync one block. The block number is
27 * from_coh_ulong(*blockp) if convert=1, *blockp if convert=0.
28 */
29 static int sync_block (struct inode * inode, u32 *blockp, int convert, int wait)
30 {
31 struct buffer_head * bh;
32 u32 tmp, block;
33 struct super_block * sb;
34
35 block = tmp = *blockp;
36 if (convert)
37 block = from_coh_ulong(block);
38 if (!block)
39 return 0;
40 sb = inode->i_sb;
41 bh = sv_get_hash_table(sb, inode->i_dev, block);
42 if (!bh)
43 return 0;
44 if (*blockp != 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 /* Sync one block full of indirect pointers and read it because we'll need it. */
62 static int sync_iblock (struct inode * inode, u32 * iblockp, int convert,
63 struct buffer_head * *bh, int wait)
64 {
65 int rc;
66 u32 tmp, block;
67
68 *bh = NULL;
69 block = tmp = *iblockp;
70 if (convert)
71 block = from_coh_ulong(block);
72 if (!block)
73 return 0;
74 rc = sync_block (inode, iblockp, convert, wait);
75 if (rc)
76 return rc;
77 *bh = sv_bread(inode->i_sb, inode->i_dev, block);
78 if (tmp != *iblockp) {
79 brelse(*bh);
80 *bh = NULL;
81 return 1;
82 }
83 if (!*bh)
84 return -1;
85 return 0;
86 }
87
88
89 static int sync_direct(struct inode *inode, int wait)
90 {
91 int i;
92 int rc, err = 0;
93
94 for (i = 0; i < 10; i++) {
95 rc = sync_block (inode, inode->u.sysv_i.i_data + i, 0, wait);
96 if (rc > 0)
97 break;
98 if (rc)
99 err = rc;
100 }
101 return err;
102 }
103
104 static int sync_indirect(struct inode *inode, u32 *iblockp, int convert, int wait)
105 {
106 int i;
107 struct buffer_head * ind_bh;
108 int rc, err = 0;
109 struct super_block * sb;
110
111 rc = sync_iblock (inode, iblockp, convert, &ind_bh, wait);
112 if (rc || !ind_bh)
113 return rc;
114
115 sb = inode->i_sb;
116 for (i = 0; i < sb->sv_ind_per_block; i++) {
117 rc = sync_block (inode,
118 ((u32 *) ind_bh->b_data) + i, sb->sv_convert,
119 wait);
120 if (rc > 0)
121 break;
122 if (rc)
123 err = rc;
124 }
125 brelse(ind_bh);
126 return err;
127 }
128
129 static int sync_dindirect(struct inode *inode, u32 *diblockp, int convert,
130 int wait)
131 {
132 int i;
133 struct buffer_head * dind_bh;
134 int rc, err = 0;
135 struct super_block * sb;
136
137 rc = sync_iblock (inode, diblockp, convert, &dind_bh, wait);
138 if (rc || !dind_bh)
139 return rc;
140
141 sb = inode->i_sb;
142 for (i = 0; i < sb->sv_ind_per_block; i++) {
143 rc = sync_indirect (inode,
144 ((u32 *) dind_bh->b_data) + i, sb->sv_convert,
145 wait);
146 if (rc > 0)
147 break;
148 if (rc)
149 err = rc;
150 }
151 brelse(dind_bh);
152 return err;
153 }
154
155 static int sync_tindirect(struct inode *inode, u32 *tiblockp, int convert,
156 int wait)
157 {
158 int i;
159 struct buffer_head * tind_bh;
160 int rc, err = 0;
161 struct super_block * sb;
162
163 rc = sync_iblock (inode, tiblockp, convert, &tind_bh, wait);
164 if (rc || !tind_bh)
165 return rc;
166
167 sb = inode->i_sb;
168 for (i = 0; i < sb->sv_ind_per_block; i++) {
169 rc = sync_dindirect (inode,
170 ((u32 *) tind_bh->b_data) + i, sb->sv_convert,
171 wait);
172 if (rc > 0)
173 break;
174 if (rc)
175 err = rc;
176 }
177 brelse(tind_bh);
178 return err;
179 }
180
181 int sysv_sync_file(struct file * file, struct dentry *dentry, int datasync)
182 {
183 int wait, err = 0;
184 struct inode *inode = dentry->d_inode;
185
186 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
187 S_ISLNK(inode->i_mode)))
188 return -EINVAL;
189
190 lock_kernel();
191 for (wait=0; wait<=1; wait++) {
192 err |= sync_direct(inode, wait);
193 err |= sync_indirect(inode, inode->u.sysv_i.i_data+10, 0, wait);
194 err |= sync_dindirect(inode, inode->u.sysv_i.i_data+11, 0, wait);
195 err |= sync_tindirect(inode, inode->u.sysv_i.i_data+12, 0, wait);
196 }
197 err |= sysv_sync_inode (inode);
198 unlock_kernel();
199 return (err < 0) ? -EIO : 0;
200 }
201
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