36bd28c1cb
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>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.