772a7a724f
Some protocols implemented in userspace with FunctionFS might require large buffers, e.g. 64kB or more. Currently the said memory is allocated with kmalloc, which might fail should system memory be highly fragmented. On the other hand, some UDC hardware allows scatter-gather operation and this patch takes advantage of this capability: if the requested buffer is larger than PAGE_SIZE and the UDC allows scatter-gather operation, then the buffer is allocated with vmalloc and a scatterlist describing it is created and passed to usb request. Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
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.