5567d4d9e7
Starting with IPA v4.5, IP payload checksum offload is implemented differently. Prior to v4.5, the IPA hardware appends an rmnet_map_dl_csum_trailer structure to each packet if checksum offload is enabled in the download direction (modem->AP). In the upload direction (AP->modem) a rmnet_map_ul_csum_header structure is prepended before each sent packet. Starting with IPA v4.5, checksum offload is implemented using a single new rmnet_map_v5_csum_header structure which sits between the QMAP header and the packet data. The same header structure is used in both directions. The new header contains a header type (CSUM_OFFLOAD); a checksum flag; and a flag indicating whether any other headers follow this one. The checksum flag indicates whether the hardware should compute (and insert) the checksum on a sent packet. On a received packet the checksum flag indicates whether the hardware confirms the checksum value in the payload is correct. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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.