ba86ceee9d
When checking whether an skb needs to be linearized to fit into an IO buffer, it's desirable to consider the skb's final size and layout (ie. after the HW header was added). But a subsequent linearization can then cause the re-positioned HW header to violate its alignment restrictions. Dealing with this situation in two different code paths is quite tricky. This patch integrates a) linearize-check and b) HW header construction into one 3 step-sequence: 1. evaluate how the HW header needs to be added (to identify if it takes up an additional buffer element), then 2. check if the required buffer elements exceed the device's limit. Linearize when necessary and re-evaluate the HW header placement. 3. Add the HW header in the best-possible way: a) push, without taking up an additional buffer element b) push, but consume another buffer element c) allocate a header object from the cache. Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> 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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.