Re: [PATCH] btrfs-progs: add recursive subvol delete

[Qu Wenruo <quwenruo.btrfs@gmx.com>]

在 2024/6/28 00:51, Mark Harmstone 写道:
> From: Omar Sandoval <osandov@fb.com>
>
> Adds a --recursive option to btrfs subvol delete, causing it to pass the
> BTRFS_UTIL_DELETE_SUBVOLUME_RECURSIVE flag through to libbtrfsutil.
>
> This is a resubmission of part of a patch that Omar Sandoval sent in
> 2018, which appears to have been overlooked:
> https://lore.kernel.org/linux-btrfs/e42cdc5d5287269faf4d09e8c9786d0b3adeb658.1516991902.git.osandov@fb.com/
>
> Signed-off-by: Mark Harmstone <maharmstone@meta.com>
> Co-authored-by: Mark Harmstone <maharmstone@meta.com>

Looks very reasonable to me, especially the flag is already there.

Reviewed-by: Qu Wenruo <wqu@suse.com>

Thanks,
Qu
> ---
>   Documentation/btrfs-subvolume.rst |  4 ++++
>   cmds/subvolume.c                  | 15 +++++++++++++--
>   2 files changed, 17 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/btrfs-subvolume.rst b/Documentation/btrfs-subvolume.rst
> index d1e89f15..b1f22344 100644
> --- a/Documentation/btrfs-subvolume.rst
> +++ b/Documentation/btrfs-subvolume.rst
> @@ -112,6 +112,10 @@ delete [options] [<subvolume> [<subvolume>...]], delete -i|--subvolid <subvolid>
>           -i|--subvolid <subvolid>
>                   subvolume id to be removed instead of the <path> that should point to the
>                   filesystem with the subvolume
> +
> +        -R|--recursive
> +                delete subvolumes beneath each subvolume recursively
> +
>           -v|--verbose
>                   (deprecated) alias for global *-v* option
>
> diff --git a/cmds/subvolume.c b/cmds/subvolume.c
> index 52bc8850..b4151af2 100644
> --- a/cmds/subvolume.c
> +++ b/cmds/subvolume.c
> @@ -347,6 +347,7 @@ static const char * const cmd_subvolume_delete_usage[] = {
>   	OPTLINE("-c|--commit-after", "wait for transaction commit at the end of the operation"),
>   	OPTLINE("-C|--commit-each", "wait for transaction commit after deleting each subvolume"),
>   	OPTLINE("-i|--subvolid", "subvolume id of the to be removed subvolume"),
> +	OPTLINE("-R|--recursive", "delete subvolumes beneath each subvolume recursively"),
>   	OPTLINE("-v|--verbose", "deprecated, alias for global -v option"),
>   	HELPINFO_INSERT_GLOBALS,
>   	HELPINFO_INSERT_VERBOSE,
> @@ -367,6 +368,7 @@ static int cmd_subvolume_delete(const struct cmd_struct *cmd, int argc, char **a
>   	char	*path = NULL;
>   	int commit_mode = 0;
>   	bool subvol_path_not_found = false;
> +	int flags = 0;
>   	u8 fsid[BTRFS_FSID_SIZE];
>   	u64 subvolid = 0;
>   	char uuidbuf[BTRFS_UUID_UNPARSED_SIZE];
> @@ -383,11 +385,12 @@ static int cmd_subvolume_delete(const struct cmd_struct *cmd, int argc, char **a
>   			{"commit-after", no_argument, NULL, 'c'},
>   			{"commit-each", no_argument, NULL, 'C'},
>   			{"subvolid", required_argument, NULL, 'i'},
> +			{"recursive", no_argument, NULL, 'R'},
>   			{"verbose", no_argument, NULL, 'v'},
>   			{NULL, 0, NULL, 0}
>   		};
>
> -		c = getopt_long(argc, argv, "cCi:v", long_options, NULL);
> +		c = getopt_long(argc, argv, "cCi:Rv", long_options, NULL);
>   		if (c < 0)
>   			break;
>
> @@ -401,6 +404,9 @@ static int cmd_subvolume_delete(const struct cmd_struct *cmd, int argc, char **a
>   		case 'i':
>   			subvolid = arg_strtou64(optarg);
>   			break;
> +		case 'R':
> +			flags |= BTRFS_UTIL_DELETE_SUBVOLUME_RECURSIVE;
> +			break;
>   		case 'v':
>   			bconf_be_verbose();
>   			break;
> @@ -416,6 +422,11 @@ static int cmd_subvolume_delete(const struct cmd_struct *cmd, int argc, char **a
>   	if (subvolid > 0 && check_argc_exact(argc - optind, 1))
>   		return 1;
>
> +	if (subvolid > 0 && flags & BTRFS_UTIL_DELETE_SUBVOLUME_RECURSIVE) {
> +		error("option --recursive not supported with --subvolid");
> +		return 1;
> +	}
> +
>   	pr_verbose(LOG_INFO, "Transaction commit: %s\n",
>   		   !commit_mode ? "none (default)" :
>   		   commit_mode == COMMIT_AFTER ? "at the end" : "after each");
> @@ -528,7 +539,7 @@ again:
>
>   	/* Start deleting. */
>   	if (subvolid == 0)
> -		err = btrfs_util_delete_subvolume_fd(fd, vname, 0);
> +		err = btrfs_util_delete_subvolume_fd(fd, vname, flags);
>   	else
>   		err = btrfs_util_delete_subvolume_by_id_fd(fd, subvolid);
>   	if (err) {