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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * QNX4 file system, Linux implementation.
4 *
5 * Version : 0.2.1
6 *
7 * Using parts of the xiafs filesystem.
8 *
9 * History :
10 *
11 * 01-06-1998 by Richard Frowijn : first release.
12 * 21-06-1998 by Frank Denis : dcache support, fixed error codes.
13 * 04-07-1998 by Frank Denis : first step for rmdir/unlink.
14 */
15
16#include <linux/buffer_head.h>
17#include "qnx4.h"
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 */
26static 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(KERN_WARNING "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 thislen = strlen( de->di_fname );
44 if ( thislen > namelen )
45 thislen = namelen;
46 if (len != thislen) {
47 return 0;
48 }
49 if (strncmp(name, de->di_fname, len) == 0) {
50 if ((de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK)) != 0) {
51 return 1;
52 }
53 }
54 return 0;
55}
56
57static struct buffer_head *qnx4_find_entry(int len, struct inode *dir,
58 const char *name, struct qnx4_inode_entry **res_dir, int *ino)
59{
60 unsigned long block, offset, blkofs;
61 struct buffer_head *bh;
62
63 *res_dir = NULL;
64 bh = NULL;
65 block = offset = blkofs = 0;
66 while (blkofs * QNX4_BLOCK_SIZE + offset < dir->i_size) {
67 if (!bh) {
68 block = qnx4_block_map(dir, blkofs);
69 if (block)
70 bh = sb_bread(dir->i_sb, block);
71 if (!bh) {
72 blkofs++;
73 continue;
74 }
75 }
76 *res_dir = (struct qnx4_inode_entry *) (bh->b_data + offset);
77 if (qnx4_match(len, name, bh, &offset)) {
78 *ino = block * QNX4_INODES_PER_BLOCK +
79 (offset / QNX4_DIR_ENTRY_SIZE) - 1;
80 return bh;
81 }
82 if (offset < bh->b_size) {
83 continue;
84 }
85 brelse(bh);
86 bh = NULL;
87 offset = 0;
88 blkofs++;
89 }
90 brelse(bh);
91 *res_dir = NULL;
92 return NULL;
93}
94
95struct dentry * qnx4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
96{
97 int ino;
98 struct qnx4_inode_entry *de;
99 struct qnx4_link_info *lnk;
100 struct buffer_head *bh;
101 const char *name = dentry->d_name.name;
102 int len = dentry->d_name.len;
103 struct inode *foundinode = NULL;
104
105 if (!(bh = qnx4_find_entry(len, dir, name, &de, &ino)))
106 goto out;
107 /* The entry is linked, let's get the real info */
108 if ((de->di_status & QNX4_FILE_LINK) == QNX4_FILE_LINK) {
109 lnk = (struct qnx4_link_info *) de;
110 ino = (le32_to_cpu(lnk->dl_inode_blk) - 1) *
111 QNX4_INODES_PER_BLOCK +
112 lnk->dl_inode_ndx;
113 }
114 brelse(bh);
115
116 foundinode = qnx4_iget(dir->i_sb, ino);
117 if (IS_ERR(foundinode)) {
118 QNX4DEBUG((KERN_ERR "qnx4: lookup->iget -> error %ld\n",
119 PTR_ERR(foundinode)));
120 return ERR_CAST(foundinode);
121 }
122out:
123 d_add(dentry, foundinode);
124
125 return NULL;
126}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * QNX4 file system, Linux implementation.
4 *
5 * Version : 0.2.1
6 *
7 * Using parts of the xiafs filesystem.
8 *
9 * History :
10 *
11 * 01-06-1998 by Richard Frowijn : first release.
12 * 21-06-1998 by Frank Denis : dcache support, fixed error codes.
13 * 04-07-1998 by Frank Denis : first step for rmdir/unlink.
14 */
15
16#include <linux/buffer_head.h>
17#include "qnx4.h"
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 */
26static 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(KERN_WARNING "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 thislen = strlen( de->di_fname );
44 if ( thislen > namelen )
45 thislen = namelen;
46 if (len != thislen) {
47 return 0;
48 }
49 if (strncmp(name, de->di_fname, len) == 0) {
50 if ((de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK)) != 0) {
51 return 1;
52 }
53 }
54 return 0;
55}
56
57static struct buffer_head *qnx4_find_entry(int len, struct inode *dir,
58 const char *name, struct qnx4_inode_entry **res_dir, int *ino)
59{
60 unsigned long block, offset, blkofs;
61 struct buffer_head *bh;
62
63 *res_dir = NULL;
64 bh = NULL;
65 block = offset = blkofs = 0;
66 while (blkofs * QNX4_BLOCK_SIZE + offset < dir->i_size) {
67 if (!bh) {
68 block = qnx4_block_map(dir, blkofs);
69 if (block)
70 bh = sb_bread(dir->i_sb, block);
71 if (!bh) {
72 blkofs++;
73 continue;
74 }
75 }
76 *res_dir = (struct qnx4_inode_entry *) (bh->b_data + offset);
77 if (qnx4_match(len, name, bh, &offset)) {
78 *ino = block * QNX4_INODES_PER_BLOCK +
79 (offset / QNX4_DIR_ENTRY_SIZE) - 1;
80 return bh;
81 }
82 if (offset < bh->b_size) {
83 continue;
84 }
85 brelse(bh);
86 bh = NULL;
87 offset = 0;
88 blkofs++;
89 }
90 brelse(bh);
91 *res_dir = NULL;
92 return NULL;
93}
94
95struct dentry * qnx4_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
96{
97 int ino;
98 struct qnx4_inode_entry *de;
99 struct qnx4_link_info *lnk;
100 struct buffer_head *bh;
101 const char *name = dentry->d_name.name;
102 int len = dentry->d_name.len;
103 struct inode *foundinode = NULL;
104
105 if (!(bh = qnx4_find_entry(len, dir, name, &de, &ino)))
106 goto out;
107 /* The entry is linked, let's get the real info */
108 if ((de->di_status & QNX4_FILE_LINK) == QNX4_FILE_LINK) {
109 lnk = (struct qnx4_link_info *) de;
110 ino = (le32_to_cpu(lnk->dl_inode_blk) - 1) *
111 QNX4_INODES_PER_BLOCK +
112 lnk->dl_inode_ndx;
113 }
114 brelse(bh);
115
116 foundinode = qnx4_iget(dir->i_sb, ino);
117 if (IS_ERR(foundinode))
118 QNX4DEBUG((KERN_ERR "qnx4: lookup->iget -> error %ld\n",
119 PTR_ERR(foundinode)));
120out:
121 return d_splice_alias(foundinode, dentry);
122}