[PATCH RESEND net-next] wwan: core: Support slicing in port TX flow of WWAN subsystem

[Simon Horman]

On Tue, Mar 07, 2023 at 04:11:04PM +0800, haozhe.chang at mediatek.com wrote:
> From: haozhe chang <haozhe.chang at mediatek.com>
> 
> wwan_port_fops_write inputs the SKB parameter to the TX callback of
> the WWAN device driver. However, the WWAN device (e.g., t7xx) may
> have an MTU less than the size of SKB, causing the TX buffer to be
> sliced and copied once more in the WWAN device driver.
> 
> This patch implements the slicing in the WWAN subsystem and gives
> the WWAN devices driver the option to slice(by frag_len) or not. By
> doing so, the additional memory copy is reduced.
> 
> Meanwhile, this patch gives WWAN devices driver the option to reserve
> headroom in fragments for the device-specific metadata.
> 
> Signed-off-by: haozhe chang <haozhe.chang at mediatek.com>
> Reviewed-by: Loic Poulain <loic.poulain at linaro.org>
> 
> ---
> Changes in v2
>   -send fragments to device driver by skb frag_list.
> 
> Changes in v3
>   -move frag_len and headroom_len setting to wwan_create_port.
> 
> Changes in v4
>   -change unreadable parameters to macro definition.
> 
> Changes in v5
>   -optimize comments for WWAN_NO_HEADROOM, WWAN_NO_FRAGMENT.
> 
> Changes in v6
>   -add reviewer to patch commit.

Thanks for resending.

Perhaps I am missing something terribly obvious,
but this patch does not seem to apply against net-next (anymore?).

I think it would be best to rebase and post a v7.

Also, the version was missing from the patch subject (but present in v5).