2 * QNX4 file system, Linux implementation.
6 * Using parts of the xiafs filesystem.
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.
15 #include <linux/smp_lock.h>
16 #include <linux/buffer_head.h>
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.
26 static int qnx4_match(int len, const char *name,
27 struct buffer_head *bh, unsigned long *offset)
29 struct qnx4_inode_entry *de;
33 printk("qnx4: matching unassigned buffer !\n");
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;
41 namelen = QNX4_SHORT_NAME_MAX;
43 /* "" means "." ---> so paths like "/usr/lib//libc.a" work */
44 if (!len && (de->di_fname[0] == '.') && (de->di_fname[1] == '\0')) {
47 thislen = strlen( de->di_fname );
48 if ( thislen > namelen )
53 if (strncmp(name, de->di_fname, len) == 0) {
54 if ((de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK)) != 0) {
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)
64 unsigned long block, offset, blkofs;
65 struct buffer_head *bh;
69 printk("qnx4: no superblock on dir.\n");
73 block = offset = blkofs = 0;
74 while (blkofs * QNX4_BLOCK_SIZE + offset < dir->i_size) {
76 bh = qnx4_bread(dir, blkofs, 0);
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;
89 if (offset < bh->b_size) {
102 struct dentry * qnx4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
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;
113 if (!(bh = qnx4_find_entry(len, dir, name, &de, &ino)))
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 +
124 foundinode = qnx4_iget(dir->i_sb, ino);
125 if (IS_ERR(foundinode)) {
127 QNX4DEBUG(("qnx4: lookup->iget -> error %ld\n",
128 PTR_ERR(foundinode)));
129 return ERR_CAST(foundinode);
133 d_add(dentry, foundinode);
138 #ifdef CONFIG_QNX4FS_RW
139 int qnx4_create(struct inode *dir, struct dentry *dentry, int mode,
140 struct nameidata *nd)
142 QNX4DEBUG(("qnx4: qnx4_create\n"));
149 int qnx4_rmdir(struct inode *dir, struct dentry *dentry)
151 struct buffer_head *bh;
152 struct qnx4_inode_entry *de;
157 QNX4DEBUG(("qnx4: qnx4_rmdir [%s]\n", dentry->d_name.name));
159 bh = qnx4_find_entry(dentry->d_name.len, dir, dentry->d_name.name,
165 inode = dentry->d_inode;
166 if (inode->i_ino != ino) {
171 if (!empty_dir(inode)) {
176 if (inode->i_nlink != 2) {
177 QNX4DEBUG(("empty directory has nlink!=2 (%d)\n", inode->i_nlink));
179 QNX4DEBUG(("qnx4: deleting directory\n"));
181 memset(de->di_fname, 0, sizeof de->di_fname);
183 mark_buffer_dirty_inode(bh, dir);
185 mark_inode_dirty(inode);
186 inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
187 inode_dec_link_count(dir);
197 int qnx4_unlink(struct inode *dir, struct dentry *dentry)
199 struct buffer_head *bh;
200 struct qnx4_inode_entry *de;
205 QNX4DEBUG(("qnx4: qnx4_unlink [%s]\n", dentry->d_name.name));
207 bh = qnx4_find_entry(dentry->d_name.len, dir, dentry->d_name.name,
213 inode = dentry->d_inode;
214 if (inode->i_ino != ino) {
219 if (!inode->i_nlink) {
220 QNX4DEBUG(("Deleting nonexistent file (%s:%lu), %d\n",
222 inode->i_ino, inode->i_nlink));
226 memset(de->di_fname, 0, sizeof de->di_fname);
228 mark_buffer_dirty_inode(bh, dir);
229 dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
230 mark_inode_dirty(dir);
231 inode->i_ctime = dir->i_ctime;
232 inode_dec_link_count(inode);