Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * QNX4 file system, Linux implementation. | |
3 | * | |
4 | * Version : 0.2.1 | |
5 | * | |
6 | * Using parts of the xiafs filesystem. | |
7 | * | |
8 | * History : | |
9 | * | |
10 | * 01-06-1998 by Richard Frowijn : first release. | |
11 | * 21-06-1998 by Frank Denis : dcache support, fixed error codes. | |
12 | * 04-07-1998 by Frank Denis : first step for rmdir/unlink. | |
13 | */ | |
14 | ||
1da177e4 LT |
15 | #include <linux/smp_lock.h> |
16 | #include <linux/buffer_head.h> | |
964f5369 | 17 | #include "qnx4.h" |
1da177e4 LT |
18 | |
19 | ||
20 | /* | |
21 | * check if the filename is correct. For some obscure reason, qnx writes a | |
22 | * new file twice in the directory entry, first with all possible options at 0 | |
23 | * and for a second time the way it is, they want us not to access the qnx | |
24 | * filesystem when whe are using linux. | |
25 | */ | |
26 | static int qnx4_match(int len, const char *name, | |
27 | struct buffer_head *bh, unsigned long *offset) | |
28 | { | |
29 | struct qnx4_inode_entry *de; | |
30 | int namelen, thislen; | |
31 | ||
32 | if (bh == NULL) { | |
33 | printk("qnx4: matching unassigned buffer !\n"); | |
34 | return 0; | |
35 | } | |
36 | de = (struct qnx4_inode_entry *) (bh->b_data + *offset); | |
37 | *offset += QNX4_DIR_ENTRY_SIZE; | |
38 | if ((de->di_status & QNX4_FILE_LINK) != 0) { | |
39 | namelen = QNX4_NAME_MAX; | |
40 | } else { | |
41 | namelen = QNX4_SHORT_NAME_MAX; | |
42 | } | |
43 | /* "" means "." ---> so paths like "/usr/lib//libc.a" work */ | |
44 | if (!len && (de->di_fname[0] == '.') && (de->di_fname[1] == '\0')) { | |
45 | return 1; | |
46 | } | |
47 | thislen = strlen( de->di_fname ); | |
48 | if ( thislen > namelen ) | |
49 | thislen = namelen; | |
50 | if (len != thislen) { | |
51 | return 0; | |
52 | } | |
53 | if (strncmp(name, de->di_fname, len) == 0) { | |
54 | if ((de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK)) != 0) { | |
55 | return 1; | |
56 | } | |
57 | } | |
58 | return 0; | |
59 | } | |
60 | ||
61 | static struct buffer_head *qnx4_find_entry(int len, struct inode *dir, | |
62 | const char *name, struct qnx4_inode_entry **res_dir, int *ino) | |
63 | { | |
64 | unsigned long block, offset, blkofs; | |
65 | struct buffer_head *bh; | |
66 | ||
67 | *res_dir = NULL; | |
68 | if (!dir->i_sb) { | |
69 | printk("qnx4: no superblock on dir.\n"); | |
70 | return NULL; | |
71 | } | |
72 | bh = NULL; | |
73 | block = offset = blkofs = 0; | |
74 | while (blkofs * QNX4_BLOCK_SIZE + offset < dir->i_size) { | |
75 | if (!bh) { | |
76 | bh = qnx4_bread(dir, blkofs, 0); | |
77 | if (!bh) { | |
78 | blkofs++; | |
79 | continue; | |
80 | } | |
81 | } | |
82 | *res_dir = (struct qnx4_inode_entry *) (bh->b_data + offset); | |
83 | if (qnx4_match(len, name, bh, &offset)) { | |
84 | block = qnx4_block_map( dir, blkofs ); | |
85 | *ino = block * QNX4_INODES_PER_BLOCK + | |
86 | (offset / QNX4_DIR_ENTRY_SIZE) - 1; | |
87 | return bh; | |
88 | } | |
89 | if (offset < bh->b_size) { | |
90 | continue; | |
91 | } | |
92 | brelse(bh); | |
93 | bh = NULL; | |
94 | offset = 0; | |
95 | blkofs++; | |
96 | } | |
97 | brelse(bh); | |
98 | *res_dir = NULL; | |
99 | return NULL; | |
100 | } | |
101 | ||
102 | struct dentry * qnx4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) | |
103 | { | |
104 | int ino; | |
105 | struct qnx4_inode_entry *de; | |
106 | struct qnx4_link_info *lnk; | |
107 | struct buffer_head *bh; | |
108 | const char *name = dentry->d_name.name; | |
109 | int len = dentry->d_name.len; | |
110 | struct inode *foundinode = NULL; | |
111 | ||
112 | lock_kernel(); | |
113 | if (!(bh = qnx4_find_entry(len, dir, name, &de, &ino))) | |
114 | goto out; | |
115 | /* The entry is linked, let's get the real info */ | |
116 | if ((de->di_status & QNX4_FILE_LINK) == QNX4_FILE_LINK) { | |
117 | lnk = (struct qnx4_link_info *) de; | |
118 | ino = (le32_to_cpu(lnk->dl_inode_blk) - 1) * | |
119 | QNX4_INODES_PER_BLOCK + | |
120 | lnk->dl_inode_ndx; | |
121 | } | |
122 | brelse(bh); | |
123 | ||
2b7e5bcb DH |
124 | foundinode = qnx4_iget(dir->i_sb, ino); |
125 | if (IS_ERR(foundinode)) { | |
1da177e4 | 126 | unlock_kernel(); |
2b7e5bcb DH |
127 | QNX4DEBUG(("qnx4: lookup->iget -> error %ld\n", |
128 | PTR_ERR(foundinode))); | |
129 | return ERR_CAST(foundinode); | |
1da177e4 LT |
130 | } |
131 | out: | |
132 | unlock_kernel(); | |
133 | d_add(dentry, foundinode); | |
134 | ||
135 | return NULL; | |
136 | } | |
137 | ||
138 | #ifdef CONFIG_QNX4FS_RW | |
139 | int qnx4_create(struct inode *dir, struct dentry *dentry, int mode, | |
140 | struct nameidata *nd) | |
141 | { | |
142 | QNX4DEBUG(("qnx4: qnx4_create\n")); | |
143 | if (dir == NULL) { | |
144 | return -ENOENT; | |
145 | } | |
146 | return -ENOSPC; | |
147 | } | |
148 | ||
149 | int qnx4_rmdir(struct inode *dir, struct dentry *dentry) | |
150 | { | |
151 | struct buffer_head *bh; | |
152 | struct qnx4_inode_entry *de; | |
153 | struct inode *inode; | |
154 | int retval; | |
155 | int ino; | |
156 | ||
157 | QNX4DEBUG(("qnx4: qnx4_rmdir [%s]\n", dentry->d_name.name)); | |
158 | lock_kernel(); | |
159 | bh = qnx4_find_entry(dentry->d_name.len, dir, dentry->d_name.name, | |
160 | &de, &ino); | |
161 | if (bh == NULL) { | |
162 | unlock_kernel(); | |
163 | return -ENOENT; | |
164 | } | |
165 | inode = dentry->d_inode; | |
166 | if (inode->i_ino != ino) { | |
167 | retval = -EIO; | |
168 | goto end_rmdir; | |
169 | } | |
170 | #if 0 | |
171 | if (!empty_dir(inode)) { | |
172 | retval = -ENOTEMPTY; | |
173 | goto end_rmdir; | |
174 | } | |
175 | #endif | |
176 | if (inode->i_nlink != 2) { | |
177 | QNX4DEBUG(("empty directory has nlink!=2 (%d)\n", inode->i_nlink)); | |
178 | } | |
179 | QNX4DEBUG(("qnx4: deleting directory\n")); | |
180 | de->di_status = 0; | |
181 | memset(de->di_fname, 0, sizeof de->di_fname); | |
182 | de->di_mode = 0; | |
79d25767 | 183 | mark_buffer_dirty_inode(bh, dir); |
ce71ec36 | 184 | clear_nlink(inode); |
1da177e4 LT |
185 | mark_inode_dirty(inode); |
186 | inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; | |
9a53c3a7 | 187 | inode_dec_link_count(dir); |
1da177e4 LT |
188 | retval = 0; |
189 | ||
190 | end_rmdir: | |
191 | brelse(bh); | |
192 | ||
193 | unlock_kernel(); | |
194 | return retval; | |
195 | } | |
196 | ||
197 | int qnx4_unlink(struct inode *dir, struct dentry *dentry) | |
198 | { | |
199 | struct buffer_head *bh; | |
200 | struct qnx4_inode_entry *de; | |
201 | struct inode *inode; | |
202 | int retval; | |
203 | int ino; | |
204 | ||
205 | QNX4DEBUG(("qnx4: qnx4_unlink [%s]\n", dentry->d_name.name)); | |
206 | lock_kernel(); | |
207 | bh = qnx4_find_entry(dentry->d_name.len, dir, dentry->d_name.name, | |
208 | &de, &ino); | |
209 | if (bh == NULL) { | |
210 | unlock_kernel(); | |
211 | return -ENOENT; | |
212 | } | |
213 | inode = dentry->d_inode; | |
214 | if (inode->i_ino != ino) { | |
215 | retval = -EIO; | |
216 | goto end_unlink; | |
217 | } | |
218 | retval = -EPERM; | |
219 | if (!inode->i_nlink) { | |
220 | QNX4DEBUG(("Deleting nonexistent file (%s:%lu), %d\n", | |
221 | inode->i_sb->s_id, | |
222 | inode->i_ino, inode->i_nlink)); | |
223 | inode->i_nlink = 1; | |
224 | } | |
225 | de->di_status = 0; | |
226 | memset(de->di_fname, 0, sizeof de->di_fname); | |
227 | de->di_mode = 0; | |
79d25767 | 228 | mark_buffer_dirty_inode(bh, dir); |
1da177e4 LT |
229 | dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; |
230 | mark_inode_dirty(dir); | |
1da177e4 | 231 | inode->i_ctime = dir->i_ctime; |
9a53c3a7 | 232 | inode_dec_link_count(inode); |
1da177e4 LT |
233 | retval = 0; |
234 | ||
235 | end_unlink: | |
236 | unlock_kernel(); | |
237 | brelse(bh); | |
238 | ||
239 | return retval; | |
240 | } | |
241 | #endif |