tree ab7c0df0819c420846ac47c18ddc0fd614eaf035
parent c0c77d8fb787cfe0c3fca689c2a30d1dad4eaba7
author Magnus Karlsson <magnus.karlsson@intel.com> 1525258884 +0200
committer Alexei Starovoitov <ast@kernel.org> 1525388123 -0700

xsk: add umem fill queue support and mmap

Here, we add another setsockopt for registered user memory (umem)
called XDP_UMEM_FILL_QUEUE. Using this socket option, the process can
ask the kernel to allocate a queue (ring buffer) and also mmap it
(XDP_UMEM_PGOFF_FILL_QUEUE) into the process.

The queue is used to explicitly pass ownership of umem frames from the
user process to the kernel. These frames will in a later patch be
filled in with Rx packet data by the kernel.

v2: Fixed potential crash in xsk_mmap.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>