Re: [PATCH v6 03/16] fs: add generic FS_IOC_SHUTDOWN definitions

From: Jan Kara

Date: Tue Feb 03 2026 - 03:54:56 EST


On Tue 03-02-26 07:01:49, Namjae Jeon wrote:
> Currently, several filesystems (e.g., xfs, ext4, btrfs) implement
> a "shutdown" or "going down" ioctl to simulate filesystem force a shutdown.
> While they often use the same underlying numeric value, the definition is
> duplicated across filesystem headers or private definitions.
>
> This patch adds generic definitions for FS_IOC_SHUTDOWN in uapi/linux/fs.h.
> This allows new filesystems (like ntfs) to implement this feature using
> a standard VFS definition and paves the way for existing filesystems
> to unify their definitions later.
>
> The flag names are standardized as FS_SHUTDOWN_* to be consistent with
> the ioctl name, replacing the historical GOING_DOWN naming convention.
>
> Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>

Good idea. Feel free to add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

Honza

> ---
> include/uapi/linux/fs.h | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
> index 66ca526cf786..32e24778c9e5 100644
> --- a/include/uapi/linux/fs.h
> +++ b/include/uapi/linux/fs.h
> @@ -656,4 +656,16 @@ struct procmap_query {
> __u64 build_id_addr; /* in */
> };
>
> +/*
> + * Shutdown the filesystem.
> + */
> +#define FS_IOC_SHUTDOWN _IOR('X', 125, __u32)
> +
> +/*
> + * Flags for FS_IOC_SHUTDOWN
> + */
> +#define FS_SHUTDOWN_FLAGS_DEFAULT 0x0
> +#define FS_SHUTDOWN_FLAGS_LOGFLUSH 0x1 /* flush log but not data*/
> +#define FS_SHUTDOWN_FLAGS_NOLOGFLUSH 0x2 /* don't flush log nor data */
> +
> #endif /* _UAPI_LINUX_FS_H */
> --
> 2.25.1
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR