Commit d206e9c9 authored by Naohiro Aota's avatar Naohiro Aota Committed by David Sterba
Browse files

btrfs: disallow NODATACOW in ZONED mode 



NODATACOW implies overwriting the file data on a device, which is
impossible in sequential required zones. Disable NODATACOW globally with
mount option and per-file NODATACOW attribute by masking FS_NOCOW_FL.

Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: default avatarNaohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 5d1ab66c

fs/btrfs/ioctl.c

+13 −0
Original line number Diff line number Diff line
@@ -193,6 +193,15 @@ static int check_fsflags(unsigned int old_flags, unsigned int flags) 
	return 0;

}



static int check_fsflags_compatible(struct btrfs_fs_info *fs_info,

				    unsigned int flags)

{

	if (btrfs_is_zoned(fs_info) && (flags & FS_NOCOW_FL))

		return -EPERM;



	return 0;

}



static int btrfs_ioctl_setflags(struct file *file, void __user *arg)

{

	struct inode *inode = file_inode(file);
@@ -230,6 +239,10 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg) 
	if (ret)

		goto out_unlock;



	ret = check_fsflags_compatible(fs_info, fsflags);

	if (ret)

		goto out_unlock;



	binode_flags = binode->flags;

	if (fsflags & FS_SYNC_FL)

		binode_flags |= BTRFS_INODE_SYNC;

fs/btrfs/zoned.c

+5 −0
Original line number Diff line number Diff line
@@ -274,5 +274,10 @@ int btrfs_check_mountopts_zoned(struct btrfs_fs_info *info) 
		return -EINVAL;

	}



	if (btrfs_test_opt(info, NODATACOW)) {

		btrfs_err(info, "zoned: NODATACOW not supported");

		return -EINVAL;

	}



	return 0;

}