[Intel-xe] [PATCH 1/2] drm/xe: Add explicit padding to uAPI definition

[Souza, Jose]

On Tue, 2023-05-23 at 20:31 -0700, Christopher Snowhill wrote:
> Pad the uAPI definition so that it would align identically between
> 64-bit and 32-bit uarch, so consumers using this header will work
> correctly from 32-bit compat userspace on a 64-bit kernel. Do it
> in a minimally invasive way, so that 64-bit userspace will still
> work with the previous header, and so that no fields suddenly
> change sizes.
> 
> Originally inspired by mlankhorst.
> 

Reviewed-by: José Roberto de Souza <jose.souza at intel.com>

> Signed-off-by: Christopher Snowhill <kode54 at gmail.com>
> ---
>  include/uapi/drm/xe_drm.h | 34 +++++++++++++++++++++++++++++++++-
>  1 file changed, 33 insertions(+), 1 deletion(-)
> 
> diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
> index b0b80aae3ee8..d5fc54b5be74 100644
> --- a/include/uapi/drm/xe_drm.h
> +++ b/include/uapi/drm/xe_drm.h
> @@ -91,7 +91,7 @@ struct xe_user_extension {
>  	 */
>  	__u32 name;
>  	/**
> -	 * @flags: MBZ
> +	 * @pad: MBZ
>  	 *
>  	 * All undefined bits must be zero.
>  	 */
> @@ -291,6 +291,9 @@ struct drm_xe_gem_create {
>  	 */
>  	__u32 handle;
>  
> +	/** @pad: MBZ */
> +	__u32 pad;
> +
>  	/** @reserved: Reserved */
>  	__u64 reserved[2];
>  };
> @@ -335,6 +338,9 @@ struct drm_xe_ext_vm_set_property {
>  #define XE_VM_PROPERTY_BIND_OP_ERROR_CAPTURE_ADDRESS		0
>  	__u32 property;
>  
> +	/** @pad: MBZ */
> +	__u32 pad;
> +
>  	/** @value: property value */
>  	__u64 value;
>  
> @@ -379,6 +385,9 @@ struct drm_xe_vm_bind_op {
>  	 */
>  	__u32 obj;
>  
> +	/** @pad: MBZ */
> +	__u32 pad;
> +
>  	union {
>  		/**
>  		 * @obj_offset: Offset into the object, MBZ for CLEAR_RANGE,
> @@ -469,6 +478,9 @@ struct drm_xe_vm_bind {
>  	/** @num_binds: number of binds in this IOCTL */
>  	__u32 num_binds;
>  
> +	/** @pad: MBZ */
> +	__u32 pad;
> +
>  	union {
>  		/** @bind: used if num_binds == 1 */
>  		struct drm_xe_vm_bind_op bind;
> @@ -482,6 +494,9 @@ struct drm_xe_vm_bind {
>  	/** @num_syncs: amount of syncs to wait on */
>  	__u32 num_syncs;
>  
> +	/** @pad2: MBZ */
> +	__u32 pad2;
> +
>  	/** @syncs: pointer to struct drm_xe_sync array */
>  	__u64 syncs;
>  
> @@ -497,6 +512,9 @@ struct drm_xe_ext_engine_set_property {
>  	/** @property: property to set */
>  	__u32 property;
>  
> +	/** @pad: MBZ */
> +	__u32 pad;
> +
>  	/** @value: property value */
>  	__u64 value;
>  };
> @@ -612,6 +630,9 @@ struct drm_xe_sync {
>  #define DRM_XE_SYNC_USER_FENCE		0x3
>  #define DRM_XE_SYNC_SIGNAL		0x10
>  
> +	/** @pad: MBZ */
> +	__u32 pad;
> +
>  	union {
>  		__u32 handle;
>  		/**
> @@ -656,6 +677,9 @@ struct drm_xe_exec {
>  	 */
>  	__u16 num_batch_buffer;
>  
> +	/** @pad: MBZ */
> +	__u16 pad[3];
> +
>  	/** @reserved: Reserved */
>  	__u64 reserved[2];
>  };
> @@ -718,6 +742,8 @@ struct drm_xe_wait_user_fence {
>  #define DRM_XE_UFENCE_WAIT_ABSTIME	(1 << 1)
>  #define DRM_XE_UFENCE_WAIT_VM_ERROR	(1 << 2)
>  	__u16 flags;
> +	/** @pad: MBZ */
> +	__u32 pad;
>  	/** @value: compare value */
>  	__u64 value;
>  	/** @mask: comparison mask */
> @@ -750,6 +776,9 @@ struct drm_xe_vm_madvise {
>  	/** @vm_id: The ID VM in which the VMA exists */
>  	__u32 vm_id;
>  
> +	/** @pad: MBZ */
> +	__u32 pad;
> +
>  	/** @range: Number of bytes in the VMA */
>  	__u64 range;
>  
> @@ -794,6 +823,9 @@ struct drm_xe_vm_madvise {
>  	/** @property: property to set */
>  	__u32 property;
>  
> +	/** @pad2: MBZ */
> +	__u32 pad2;
> +
>  	/** @value: property value */
>  	__u64 value;
>