1 // SPDX-License-Identifier: GPL-2.0
3 * QNX6 file system, Linux implementation.
9 * 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
13 #include <linux/buffer_head.h>
14 #include <linux/slab.h>
15 #include <linux/crc32.h>
18 static void qnx6_mmi_copy_sb(struct qnx6_super_block
*qsb
,
19 struct qnx6_mmi_super_block
*sb
)
21 qsb
->sb_magic
= sb
->sb_magic
;
22 qsb
->sb_checksum
= sb
->sb_checksum
;
23 qsb
->sb_serial
= sb
->sb_serial
;
24 qsb
->sb_blocksize
= sb
->sb_blocksize
;
25 qsb
->sb_num_inodes
= sb
->sb_num_inodes
;
26 qsb
->sb_free_inodes
= sb
->sb_free_inodes
;
27 qsb
->sb_num_blocks
= sb
->sb_num_blocks
;
28 qsb
->sb_free_blocks
= sb
->sb_free_blocks
;
30 /* the rest of the superblock is the same */
31 memcpy(&qsb
->Inode
, &sb
->Inode
, sizeof(sb
->Inode
));
32 memcpy(&qsb
->Bitmap
, &sb
->Bitmap
, sizeof(sb
->Bitmap
));
33 memcpy(&qsb
->Longfile
, &sb
->Longfile
, sizeof(sb
->Longfile
));
36 struct qnx6_super_block
*qnx6_mmi_fill_super(struct super_block
*s
, int silent
)
38 struct buffer_head
*bh1
, *bh2
= NULL
;
39 struct qnx6_mmi_super_block
*sb1
, *sb2
;
40 struct qnx6_super_block
*qsb
= NULL
;
41 struct qnx6_sb_info
*sbi
;
44 /* Check the superblock signatures
45 start with the first superblock */
48 pr_err("Unable to read first mmi superblock\n");
51 sb1
= (struct qnx6_mmi_super_block
*)bh1
->b_data
;
53 if (fs32_to_cpu(sbi
, sb1
->sb_magic
) != QNX6_SUPER_MAGIC
) {
55 pr_err("wrong signature (magic) in superblock #1.\n");
60 /* checksum check - start at byte 8 and end at byte 512 */
61 if (fs32_to_cpu(sbi
, sb1
->sb_checksum
) !=
62 crc32_be(0, (char *)(bh1
->b_data
+ 8), 504)) {
63 pr_err("superblock #1 checksum error\n");
67 /* calculate second superblock blocknumber */
68 offset
= fs32_to_cpu(sbi
, sb1
->sb_num_blocks
) + QNX6_SUPERBLOCK_AREA
/
69 fs32_to_cpu(sbi
, sb1
->sb_blocksize
);
71 /* set new blocksize */
72 if (!sb_set_blocksize(s
, fs32_to_cpu(sbi
, sb1
->sb_blocksize
))) {
73 pr_err("unable to set blocksize\n");
76 /* blocksize invalidates bh - pull it back in */
81 sb1
= (struct qnx6_mmi_super_block
*)bh1
->b_data
;
83 /* read second superblock */
84 bh2
= sb_bread(s
, offset
);
86 pr_err("unable to read the second superblock\n");
89 sb2
= (struct qnx6_mmi_super_block
*)bh2
->b_data
;
90 if (fs32_to_cpu(sbi
, sb2
->sb_magic
) != QNX6_SUPER_MAGIC
) {
92 pr_err("wrong signature (magic) in superblock #2.\n");
96 /* checksum check - start at byte 8 and end at byte 512 */
97 if (fs32_to_cpu(sbi
, sb2
->sb_checksum
)
98 != crc32_be(0, (char *)(bh2
->b_data
+ 8), 504)) {
99 pr_err("superblock #1 checksum error\n");
103 qsb
= kmalloc(sizeof(*qsb
), GFP_KERNEL
);
105 pr_err("unable to allocate memory.\n");
109 if (fs64_to_cpu(sbi
, sb1
->sb_serial
) >
110 fs64_to_cpu(sbi
, sb2
->sb_serial
)) {
111 /* superblock #1 active */
112 qnx6_mmi_copy_sb(qsb
, sb1
);
113 #ifdef CONFIG_QNX6FS_DEBUG
114 qnx6_superblock_debug(qsb
, s
);
116 memcpy(bh1
->b_data
, qsb
, sizeof(struct qnx6_super_block
));
119 sbi
->sb
= (struct qnx6_super_block
*)bh1
->b_data
;
121 pr_info("superblock #1 active\n");
123 /* superblock #2 active */
124 qnx6_mmi_copy_sb(qsb
, sb2
);
125 #ifdef CONFIG_QNX6FS_DEBUG
126 qnx6_superblock_debug(qsb
, s
);
128 memcpy(bh2
->b_data
, qsb
, sizeof(struct qnx6_super_block
));
131 sbi
->sb
= (struct qnx6_super_block
*)bh2
->b_data
;
133 pr_info("superblock #2 active\n");
137 /* offset for mmi_fs is just SUPERBLOCK_AREA bytes */
138 sbi
->s_blks_off
= QNX6_SUPERBLOCK_AREA
/ s
->s_blocksize
;