Re: [RFC 2/4] media: Rearrange the fields in the G_TOPOLOGY IOCTL argument

Mauro Carvalho Chehab
2016-02-22T09:54:21Z

Em Sun, 21 Feb 2016 23:36:13 +0200
Sakari Ailus <sakari.ailus@linux.intel.com> escreveu:

> From: Sakari Ailus <sakari.ailus@iki.fi>
>
> This avoids having multiple reserved fields in the struct. Reserved fields
> are added in order to align the struct size to a power of two as well.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> ---
> include/uapi/linux/media.h | 15 +++++----------
> 1 file changed, 5 insertions(+), 10 deletions(-)
>
> diff --git a/include/uapi/linux/media.h b/include/uapi/linux/media.h
> index 008d077..77a95db 100644
> --- a/include/uapi/linux/media.h
> +++ b/include/uapi/linux/media.h
> @@ -341,21 +341,16 @@ struct media_v2_link {
> struct media_v2_topology {
> __u64 topology_version;
>
> - __u32 num_entities;
> - __u32 reserved1;
> __u64 ptr_entities;
> -
> - __u32 num_interfaces;
> - __u32 reserved2;
> __u64 ptr_interfaces;
> -
> - __u32 num_pads;
> - __u32 reserved3;
> __u64 ptr_pads;
> + __u64 ptr_links;
>
> + __u32 num_entities;
> + __u32 num_interfaces;
> + __u32 num_pads;
> __u32 num_links;
> - __u32 reserved4;
> - __u64 ptr_links;
> + __u32 reserved[18];
> };

This patch deserves more discussion. I suggest we discuss it on our
next IRC meeting about the MC (likely today).

>
> static inline void __user *media_get_uptr(__u64 arg)

--
Thanks,
Mauro