btrfs-progs: super-recover: Reuse btrfs_read_dev_super function

We have enhanced super block validation check in disk_io.c, while
super-recover doesn't use that function and use a custom one.

That is duplicated, so reuse btrfs_read_dev_super to handle it, which
not only enhanced super check, but also reduce the code length.

Reported-by: hawken <hawken@thehawken.org>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Qu Wenruo 2016-09-20 10:19:02 +08:00 committed by David Sterba
parent 50c8c995ea
commit 3296d058b7

View File

@ -88,24 +88,6 @@ void free_recover_superblock(struct btrfs_recover_superblock *recover)
}
}
static int check_super(u64 bytenr, struct btrfs_super_block *sb)
{
int csum_size = btrfs_super_csum_size(sb);
u8 result[csum_size];
u32 crc = ~(u32)0;
if (btrfs_super_bytenr(sb) != bytenr)
return 0;
if (sb->magic != cpu_to_le64(BTRFS_MAGIC))
return 0;
crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE,
crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
btrfs_csum_final(crc, result);
return !memcmp(sb, &result, csum_size);
}
static int add_superblock_record(struct btrfs_super_block *sb, char *fname,
u64 bytenr, struct list_head *head)
{
@ -133,24 +115,20 @@ read_dev_supers(char *filename, struct btrfs_recover_superblock *recover)
int i, ret, fd;
u8 buf[BTRFS_SUPER_INFO_SIZE];
u64 max_gen, bytenr;
struct btrfs_super_block *sb = (struct btrfs_super_block *)buf;
/* just ignore errno that were set in btrfs_scan_fs_devices() */
errno = 0;
struct btrfs_super_block *sb = (struct btrfs_super_block *)buf;
fd = open(filename, O_RDONLY);
if (fd < 0)
return -errno;
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
ret = pread64(fd, buf, sizeof(buf), bytenr);
if (ret < sizeof(buf)) {
ret = -errno;
goto out;
}
ret = check_super(bytenr, sb);
if (ret) {
ret = btrfs_read_dev_super(fd, sb, bytenr, SBREAD_DEFAULT);
if (!ret) {
ret = add_superblock_record(sb, filename, bytenr,
&recover->good_supers);
if (ret)
@ -158,13 +136,18 @@ read_dev_supers(char *filename, struct btrfs_recover_superblock *recover)
max_gen = btrfs_super_generation(sb);
if (max_gen > recover->max_generation)
recover->max_generation = max_gen;
} else {
} else if (ret == -EIO){
/*
* Skip superblock which doesn't exist, only adds
* really corrupted superblock
*/
ret = add_superblock_record(sb, filename, bytenr,
&recover->bad_supers);
if (ret)
goto out;
}
}
ret = 0;
out:
close(fd);
return ret;