| Message ID | 20160920021902.818-1-quwenruo@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Sep 20, 2016 at 10:19:01AM +0800, Qu Wenruo wrote: > btrfs_read_dev_super() only returns 0 or -1, which doesn't really help, > caller won't know if it's caused by bad superblock or superblock out of > range. > > Change it to return -ENOENT for superblock which is out of range, and > return -EIO for bad superblocks. > > Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> > --- > disk-io.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/disk-io.c b/disk-io.c > index 854c285..26852ee 100644 > --- a/disk-io.c > +++ b/disk-io.c > @@ -1590,14 +1590,15 @@ int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr, > > if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) { > ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, sb_bytenr); pread64 sets errno, should be returned > + /* Special return value for out of dev/file range */ > if (ret < BTRFS_SUPER_INFO_SIZE) > - return -1; > + return -ENOENT; > > if (btrfs_super_bytenr(buf) != sb_bytenr) > - return -1; > + return -EIO; > > if (check_super(buf, sbflags)) > - return -1; > + return -EIO; and we should return what check_super returns, though it's -EIO in most cases. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/disk-io.c b/disk-io.c index 854c285..26852ee 100644 --- a/disk-io.c +++ b/disk-io.c @@ -1590,14 +1590,15 @@ int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr, if (sb_bytenr != BTRFS_SUPER_INFO_OFFSET) { ret = pread64(fd, buf, BTRFS_SUPER_INFO_SIZE, sb_bytenr); + /* Special return value for out of dev/file range */ if (ret < BTRFS_SUPER_INFO_SIZE) - return -1; + return -ENOENT; if (btrfs_super_bytenr(buf) != sb_bytenr) - return -1; + return -EIO; if (check_super(buf, sbflags)) - return -1; + return -EIO; memcpy(sb, buf, BTRFS_SUPER_INFO_SIZE); return 0; } @@ -1641,7 +1642,7 @@ int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr, } } - return transid > 0 ? 0 : -1; + return transid > 0 ? 0 : -EIO; } static int write_dev_supers(struct btrfs_root *root,
btrfs_read_dev_super() only returns 0 or -1, which doesn't really help, caller won't know if it's caused by bad superblock or superblock out of range. Change it to return -ENOENT for superblock which is out of range, and return -EIO for bad superblocks. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> --- disk-io.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)