diff options
| author | haozhe chang <haozhe.chang@mediatek.com> | 2023-03-16 17:58:20 +0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-03-17 22:38:31 -0700 |
| commit | 36bd28c1cb0dbf48645cfe43159907fb3253b33a (patch) | |
| tree | e03798a8e0af020702b53da1da3d52ed6621fb22 /include/linux/wwan.h | |
| parent | ed0578a46c5f08647f5ecb0e3c735a53267426f7 (diff) | |
wwan: core: Support slicing in port TX flow of WWAN subsystem
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@mediatek.com>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Link: https://lore.kernel.org/r/20230316095826.181904-1-haozhe.chang@mediatek.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/linux/wwan.h')
| -rw-r--r-- | include/linux/wwan.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/include/linux/wwan.h b/include/linux/wwan.h index 24d76500b1cc..01fa15506286 100644 --- a/include/linux/wwan.h +++ b/include/linux/wwan.h @@ -64,11 +64,21 @@ struct wwan_port_ops { poll_table *wait); }; +/** struct wwan_port_caps - The WWAN port capbilities + * @frag_len: WWAN port TX fragments length + * @headroom_len: WWAN port TX fragments reserved headroom length + */ +struct wwan_port_caps { + size_t frag_len; + unsigned int headroom_len; +}; + /** * wwan_create_port - Add a new WWAN port * @parent: Device to use as parent and shared by all WWAN ports * @type: WWAN port type * @ops: WWAN port operations + * @caps: WWAN port capabilities * @drvdata: Pointer to caller driver data * * Allocate and register a new WWAN port. The port will be automatically exposed @@ -86,6 +96,7 @@ struct wwan_port_ops { struct wwan_port *wwan_create_port(struct device *parent, enum wwan_port_type type, const struct wwan_port_ops *ops, + struct wwan_port_caps *caps, void *drvdata); /** |