mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-11-01 17:08:10 +00:00
5d026c7242
Adds support for qnx6fs readonly support to the linux kernel. * Mount option The option mmi_fs can be used to mount Harman Becker/Audi MMI 3G HDD qnx6fs filesystems. * Documentation A high level filesystem stucture description can be found in the Documentation/filesystems directory. (qnx6.txt) * Additional features - Active (stable) superblock selection - Superblock checksum check (enforced) - Supports mount of qnx6 filesystems with to host different endianess - Automatic endianess detection - Longfilename support (with non-enfocing crc check) - All blocksizes (512, 1024, 2048 and 4096 supported) Signed-off-by: Kai Bankett <chaosman@ontika.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
150 lines
3.9 KiB
C
150 lines
3.9 KiB
C
/*
|
|
* QNX6 file system, Linux implementation.
|
|
*
|
|
* Version : 1.0.0
|
|
*
|
|
* History :
|
|
*
|
|
* 01-02-2012 by Kai Bankett (chaosman@ontika.net) : first release.
|
|
*
|
|
*/
|
|
|
|
#include <linux/buffer_head.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/crc32.h>
|
|
#include "qnx6.h"
|
|
|
|
static void qnx6_mmi_copy_sb(struct qnx6_super_block *qsb,
|
|
struct qnx6_mmi_super_block *sb)
|
|
{
|
|
qsb->sb_magic = sb->sb_magic;
|
|
qsb->sb_checksum = sb->sb_checksum;
|
|
qsb->sb_serial = sb->sb_serial;
|
|
qsb->sb_blocksize = sb->sb_blocksize;
|
|
qsb->sb_num_inodes = sb->sb_num_inodes;
|
|
qsb->sb_free_inodes = sb->sb_free_inodes;
|
|
qsb->sb_num_blocks = sb->sb_num_blocks;
|
|
qsb->sb_free_blocks = sb->sb_free_blocks;
|
|
|
|
/* the rest of the superblock is the same */
|
|
memcpy(&qsb->Inode, &sb->Inode, sizeof(sb->Inode));
|
|
memcpy(&qsb->Bitmap, &sb->Bitmap, sizeof(sb->Bitmap));
|
|
memcpy(&qsb->Longfile, &sb->Longfile, sizeof(sb->Longfile));
|
|
}
|
|
|
|
struct qnx6_super_block *qnx6_mmi_fill_super(struct super_block *s, int silent)
|
|
{
|
|
struct buffer_head *bh1, *bh2 = NULL;
|
|
struct qnx6_mmi_super_block *sb1, *sb2;
|
|
struct qnx6_super_block *qsb = NULL;
|
|
struct qnx6_sb_info *sbi;
|
|
__u64 offset;
|
|
|
|
/* Check the superblock signatures
|
|
start with the first superblock */
|
|
bh1 = sb_bread(s, 0);
|
|
if (!bh1) {
|
|
printk(KERN_ERR "qnx6: Unable to read first mmi superblock\n");
|
|
return NULL;
|
|
}
|
|
sb1 = (struct qnx6_mmi_super_block *)bh1->b_data;
|
|
sbi = QNX6_SB(s);
|
|
if (fs32_to_cpu(sbi, sb1->sb_magic) != QNX6_SUPER_MAGIC) {
|
|
if (!silent) {
|
|
printk(KERN_ERR "qnx6: wrong signature (magic) in"
|
|
" superblock #1.\n");
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/* checksum check - start at byte 8 and end at byte 512 */
|
|
if (fs32_to_cpu(sbi, sb1->sb_checksum) !=
|
|
crc32_be(0, (char *)(bh1->b_data + 8), 504)) {
|
|
printk(KERN_ERR "qnx6: superblock #1 checksum error\n");
|
|
goto out;
|
|
}
|
|
|
|
/* calculate second superblock blocknumber */
|
|
offset = fs32_to_cpu(sbi, sb1->sb_num_blocks) + QNX6_SUPERBLOCK_AREA /
|
|
fs32_to_cpu(sbi, sb1->sb_blocksize);
|
|
|
|
/* set new blocksize */
|
|
if (!sb_set_blocksize(s, fs32_to_cpu(sbi, sb1->sb_blocksize))) {
|
|
printk(KERN_ERR "qnx6: unable to set blocksize\n");
|
|
goto out;
|
|
}
|
|
/* blocksize invalidates bh - pull it back in */
|
|
brelse(bh1);
|
|
bh1 = sb_bread(s, 0);
|
|
if (!bh1)
|
|
goto out;
|
|
sb1 = (struct qnx6_mmi_super_block *)bh1->b_data;
|
|
|
|
/* read second superblock */
|
|
bh2 = sb_bread(s, offset);
|
|
if (!bh2) {
|
|
printk(KERN_ERR "qnx6: unable to read the second superblock\n");
|
|
goto out;
|
|
}
|
|
sb2 = (struct qnx6_mmi_super_block *)bh2->b_data;
|
|
if (fs32_to_cpu(sbi, sb2->sb_magic) != QNX6_SUPER_MAGIC) {
|
|
if (!silent)
|
|
printk(KERN_ERR "qnx6: wrong signature (magic) in"
|
|
" superblock #2.\n");
|
|
goto out;
|
|
}
|
|
|
|
/* checksum check - start at byte 8 and end at byte 512 */
|
|
if (fs32_to_cpu(sbi, sb2->sb_checksum)
|
|
!= crc32_be(0, (char *)(bh2->b_data + 8), 504)) {
|
|
printk(KERN_ERR "qnx6: superblock #1 checksum error\n");
|
|
goto out;
|
|
}
|
|
|
|
qsb = kmalloc(sizeof(*qsb), GFP_KERNEL);
|
|
if (!qsb) {
|
|
printk(KERN_ERR "qnx6: unable to allocate memory.\n");
|
|
goto out;
|
|
}
|
|
|
|
if (fs64_to_cpu(sbi, sb1->sb_serial) >
|
|
fs64_to_cpu(sbi, sb2->sb_serial)) {
|
|
/* superblock #1 active */
|
|
qnx6_mmi_copy_sb(qsb, sb1);
|
|
#ifdef CONFIG_QNX6FS_DEBUG
|
|
qnx6_superblock_debug(qsb, s);
|
|
#endif
|
|
memcpy(bh1->b_data, qsb, sizeof(struct qnx6_super_block));
|
|
|
|
sbi->sb_buf = bh1;
|
|
sbi->sb = (struct qnx6_super_block *)bh1->b_data;
|
|
brelse(bh2);
|
|
printk(KERN_INFO "qnx6: superblock #1 active\n");
|
|
} else {
|
|
/* superblock #2 active */
|
|
qnx6_mmi_copy_sb(qsb, sb2);
|
|
#ifdef CONFIG_QNX6FS_DEBUG
|
|
qnx6_superblock_debug(qsb, s);
|
|
#endif
|
|
memcpy(bh2->b_data, qsb, sizeof(struct qnx6_super_block));
|
|
|
|
sbi->sb_buf = bh2;
|
|
sbi->sb = (struct qnx6_super_block *)bh2->b_data;
|
|
brelse(bh1);
|
|
printk(KERN_INFO "qnx6: superblock #2 active\n");
|
|
}
|
|
kfree(qsb);
|
|
|
|
/* offset for mmi_fs is just SUPERBLOCK_AREA bytes */
|
|
sbi->s_blks_off = QNX6_SUPERBLOCK_AREA / s->s_blocksize;
|
|
|
|
/* success */
|
|
return sbi->sb;
|
|
|
|
out:
|
|
if (bh1 != NULL)
|
|
brelse(bh1);
|
|
if (bh2 != NULL)
|
|
brelse(bh2);
|
|
return NULL;
|
|
}
|