Re: [PATCH] btrfs: ioctls would need unique id

[Hugo Mills <hugo@carfax.org.uk>]

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On Thu, Dec 19, 2013 at 12:06:32PM +0800, Anand Jain wrote:
> BTRFS_IOC_SET_FEATURES and BTRFS_IOC_GET_SUPPORTED_FEATURES
> conflicts with BTRFS_IOC_GET_FEATURES
> 
> Signed-off-by: Anand Jain <anand.jain@oracle.com>
> ---
>  include/uapi/linux/btrfs.h |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
> index 7d7f776..0fe736e 100644
> --- a/include/uapi/linux/btrfs.h
> +++ b/include/uapi/linux/btrfs.h
> @@ -634,9 +634,9 @@ struct btrfs_ioctl_fslist_args {
>  					struct btrfs_ioctl_fslist_args)
>  #define BTRFS_IOC_GET_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 57, \
>  				   struct btrfs_ioctl_feature_flags)
> -#define BTRFS_IOC_SET_FEATURES _IOW(BTRFS_IOCTL_MAGIC, 57, \
> +#define BTRFS_IOC_SET_FEATURES _IOW(BTRFS_IOCTL_MAGIC, 58, \
>  				   struct btrfs_ioctl_feature_flags[2])
> -#define BTRFS_IOC_GET_SUPPORTED_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 57, \
> +#define BTRFS_IOC_GET_SUPPORTED_FEATURES _IOR(BTRFS_IOCTL_MAGIC, 59, \
>  				   struct btrfs_ioctl_feature_flags[3])

   The ioctls are distinct as tehy are, as they have different-sized
parameters. Changing these numbers is changing the public interface,
which is a big no-no.

   Hugo.

-- 
=== Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk ===
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