Commit a1132430 authored Aug 28, 2020 by Magnus Karlsson Committed by Daniel Borkmann Aug 31, 2020

xsk: Add shared umem support between devices



Add support to share a umem between different devices. This mode
can be invoked with the XDP_SHARED_UMEM bind flag. Previously,
sharing was only supported within the same device. Note that when
sharing a umem between devices, just as in the case of sharing a
umem between queue ids, you need to create a fill ring and a
completion ring and tie them to the socket (with two setsockopts,
one for each ring) before you do the bind with the
XDP_SHARED_UMEM flag. This so that the single-producer
single-consumer semantics of the rings can be upheld.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/bpf/1598603189-32145-13-git-send-email-magnus.karlsson@intel.com

parent b5aea28d

net/xdp/xsk.c

+4 −7

Original line number	Diff line number	Diff line
		@@ -701,14 +701,11 @@ static int xsk_bind(struct socket sock, struct sockaddr addr, int addr_len)
		sockfd_put(sock);
		goto out_unlock;
		}
		if (umem_xs->dev != dev) {
		err = -EINVAL;
		sockfd_put(sock);
		goto out_unlock;
		}

		if (umem_xs->queue_id != qid) {
		/* Share the umem with another socket on another qid */
		if (umem_xs->queue_id != qid \|\| umem_xs->dev != dev) {
		/* Share the umem with another socket on another qid
		* and/or device.
		*/
		xs->pool = xp_create_and_assign_umem(xs,
		umem_xs->umem);
		if (!xs->pool) {

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