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>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 5a23806..7cf0f63 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2667,6 +2667,60 @@
return ret;
}
+static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
+{
+ struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
+ struct btrfs_ioctl_vol_args_v2 *vol_args;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args)) {
+ ret = PTR_ERR(vol_args);
+ goto err_drop;
+ }
+
+ /* Check for compatibility reject unknown flags */
+ if (vol_args->flags & ~BTRFS_VOL_ARG_V2_FLAGS)
+ return -ENOTTY;
+
+ if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
+ 1)) {
+ ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
+ goto out;
+ }
+
+ mutex_lock(&root->fs_info->volume_mutex);
+ if (vol_args->flags & BTRFS_DEVICE_BY_ID) {
+ ret = btrfs_rm_device(root, NULL, vol_args->devid);
+ } else {
+ vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
+ ret = btrfs_rm_device(root, vol_args->name, 0);
+ }
+ mutex_unlock(&root->fs_info->volume_mutex);
+ atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
+
+ if (!ret) {
+ if (vol_args->flags & BTRFS_DEVICE_BY_ID)
+ btrfs_info(root->fs_info, "device deleted: id %llu",
+ vol_args->devid);
+ else
+ btrfs_info(root->fs_info, "device deleted: %s",
+ vol_args->name);
+ }
+out:
+ kfree(vol_args);
+err_drop:
+ mnt_drop_write_file(file);
+ return ret;
+}
+
static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
{
struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
@@ -2695,7 +2749,7 @@
}
mutex_lock(&root->fs_info->volume_mutex);
- ret = btrfs_rm_device(root, vol_args->name);
+ ret = btrfs_rm_device(root, vol_args->name, 0);
mutex_unlock(&root->fs_info->volume_mutex);
atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
@@ -5459,6 +5513,8 @@
return btrfs_ioctl_add_dev(root, argp);
case BTRFS_IOC_RM_DEV:
return btrfs_ioctl_rm_dev(file, argp);
+ case BTRFS_IOC_RM_DEV_V2:
+ return btrfs_ioctl_rm_dev_v2(file, argp);
case BTRFS_IOC_FS_INFO:
return btrfs_ioctl_fs_info(root, argp);
case BTRFS_IOC_DEV_INFO: