Re: [PATCH v11 02/17] Add a new struct for device to manipulate external buffer.

Ben Hutchings
2010-09-27T13:41:52Z

On Sat, 2010-09-25 at 12:27 +0800, xiaohui.xin@intel.com wrote:
> From: Xin Xiaohui <xiaohui.xin@intel.com>
>
> Signed-off-by: Xin Xiaohui <xiaohui.xin@intel.com>
> Signed-off-by: Zhao Yu <yzhao81new@gmail.com>
> Reviewed-by: Jeff Dike <jdike@linux.intel.com>
> ---
> include/linux/netdevice.h | 22 +++++++++++++++++++++-
> 1 files changed, 21 insertions(+), 1 deletions(-)
>
> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> index fa8b476..ba582e1 100644
> --- a/include/linux/netdevice.h
> +++ b/include/linux/netdevice.h
> @@ -530,6 +530,25 @@ struct netdev_queue {
> unsigned long tx_dropped;
> } ____cacheline_aligned_in_smp;
>
> +/* Add a structure in structure net_device, the new field is
> + * named as mp_port. It's for mediate passthru (zero-copy).

That belongs in the commit message.

> + * It contains the capability for the net device driver,
> + * a socket, and an external buffer creator, external means
> + * skb buffer belongs to the device may not be allocated from
> + * kernel space.

Who sets which fields in this structure? Can you make this a kernel-doc
comment specifying the use of each field?

Ben.

> + */
> +struct mpassthru_port {
> + int hdr_len;
> + int data_len;
> + int npages;
> + unsigned flags;
> + struct socket *sock;
> + int vnet_hlen;
> + struct skb_ext_page *(*ctor)(struct mpassthru_port *,
> + struct sk_buff *, int);
> + struct skb_ext_page *(*hash)(struct net_device *,
> + struct page *);
> +};
>
> /*
> * This structure defines the management hooks for network devices.
> @@ -952,7 +971,8 @@ struct net_device {
> struct macvlan_port *macvlan_port;
> /* GARP */
> struct garp_port *garp_port;
> -
> + /* mpassthru */
> + struct mpassthru_port *mp_port;
> /* class/net/name entry */
> struct device dev;
> /* space for optional device, statistics, and wireless sysfs groups */

--
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.