btrfs: introduce device delete by devid

This introduces new ioctl BTRFS_IOC_RM_DEV_V2, which uses enhanced struct
btrfs_ioctl_vol_args_v2 to carry devid as an user argument.

The patch won't delete the old ioctl interface and so kernel remains
backward compatible with user land progs.

Test case/script:
echo "0 $(blockdev --getsz /dev/sdf) linear /dev/sdf 0" | dmsetup create bad_disk
mkfs.btrfs -f -d raid1 -m raid1 /dev/sdd /dev/sde /dev/mapper/bad_disk
mount /dev/sdd /btrfs
dmsetup suspend bad_disk
echo "0 $(blockdev --getsz /dev/sdf) error /dev/sdf 0" | dmsetup load bad_disk
dmsetup resume bad_disk
echo "bad disk failed. now deleting/replacing"
btrfs dev del  3  /btrfs
echo $?
btrfs fi show /btrfs
umount /btrfs
btrfs-show-super /dev/sdd | egrep num_device
dmsetup remove bad_disk
wipefs -a /dev/sdf

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reported-by: Martin <m_btrfs@ml1.co.uk>
[ adjust messages, s/disk/device/ ]
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Anand Jain 2016-02-13 10:01:39 +08:00 committed by David Sterba
parent 42b6742715
commit 6b526ed70c
4 changed files with 73 additions and 5 deletions

View file

@ -36,6 +36,13 @@ struct btrfs_ioctl_vol_args {
#define BTRFS_SUBVOL_CREATE_ASYNC (1ULL << 0)
#define BTRFS_SUBVOL_RDONLY (1ULL << 1)
#define BTRFS_SUBVOL_QGROUP_INHERIT (1ULL << 2)
#define BTRFS_DEVICE_BY_ID (1ULL << 3)
#define BTRFS_VOL_ARG_V2_FLAGS \
(BTRFS_SUBVOL_CREATE_ASYNC | \
BTRFS_SUBVOL_RDONLY | \
BTRFS_SUBVOL_QGROUP_INHERIT | \
BTRFS_DEVICE_BY_ID)
#define BTRFS_FSID_SIZE 16
#define BTRFS_UUID_SIZE 16
#define BTRFS_UUID_UNPARSED_SIZE 37
@ -76,7 +83,10 @@ struct btrfs_ioctl_vol_args_v2 {
};
__u64 unused[4];
};
char name[BTRFS_SUBVOL_NAME_MAX + 1];
union {
char name[BTRFS_SUBVOL_NAME_MAX + 1];
u64 devid;
};
};
/*
@ -659,5 +669,7 @@ static inline char *btrfs_err_str(enum btrfs_err_code err_code)
struct btrfs_ioctl_feature_flags[2])
#define BTRFS_IOC_GET_SUPPORTED_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 57, \
struct btrfs_ioctl_feature_flags[3])
#define BTRFS_IOC_RM_DEV_V2 _IOW(BTRFS_IOCTL_MAGIC, 58, \
struct btrfs_ioctl_vol_args_v2)
#endif /* _UAPI_LINUX_BTRFS_H */