Commit 47960ad6 authored Jul 25, 2020 by Alexei Starovoitov

Merge branch 'bpf_link-XDP'



Andrii Nakryiko says:

====================
Following cgroup and netns examples, implement bpf_link support for XDP.

The semantics is described in patch #2. Program and link attachments are
mutually exclusive, in the sense that neither link can replace attached
program nor program can replace attached link. Link can't replace attached
link as well, as is the case for any other bpf_link implementation.

Patch #1 refactors existing BPF program-based attachment API and centralizes
high-level query/attach decisions in generic kernel code, while drivers are
kept simple and are instructed with low-level decisions about attaching and
detaching specific bpf_prog. This also makes QUERY command unnecessary, and
patch #8 removes support for it from all kernel drivers. If that's a bad idea,
we can drop that patch altogether.

With refactoring in patch #1, adding bpf_xdp_link is completely transparent to
drivers, they are still functioning at the level of "effective" bpf_prog, that
should be called in XDP data path.

Corresponding libbpf support for BPF XDP link is added in patch #5.

v3->v4:
- fix a compilation warning in one of drivers (Jakub);

v2->v3:
- fix build when CONFIG_BPF_SYSCALL=n (kernel test robot);

v1->v2:
- fix prog refcounting bug (David);
- split dev_change_xdp_fd() changes into 2 patches (David);
- add extack messages to all user-induced errors (David).
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

parents 2b9b305f e8407fde

drivers/net/ethernet/amazon/ena/ena_netdev.c

+0 −6

Original line number	Diff line number	Diff line
		@@ -576,15 +576,9 @@ static int ena_xdp_set(struct net_device netdev, struct netdev_bpf bpf)
		*/
		static int ena_xdp(struct net_device netdev, struct netdev_bpf bpf)
		{
		struct ena_adapter *adapter = netdev_priv(netdev);

		switch (bpf->command) {
		case XDP_SETUP_PROG:
		return ena_xdp_set(netdev, bpf);
		case XDP_QUERY_PROG:
		bpf->prog_id = adapter->xdp_bpf_prog ?
		adapter->xdp_bpf_prog->aux->id : 0;
		break;
		default:
		return -EINVAL;
		}

drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c

+0 −4

Original line number	Diff line number	Diff line
		@@ -330,10 +330,6 @@ int bnxt_xdp(struct net_device dev, struct netdev_bpf xdp)
		case XDP_SETUP_PROG:
		rc = bnxt_xdp_set(bp, xdp->prog);
		break;
		case XDP_QUERY_PROG:
		xdp->prog_id = bp->xdp_prog ? bp->xdp_prog->aux->id : 0;
		rc = 0;
		break;
		default:
		rc = -EINVAL;
		break;

drivers/net/ethernet/cavium/thunder/nicvf_main.c

+0 −3

Original line number	Diff line number	Diff line
		@@ -1906,9 +1906,6 @@ static int nicvf_xdp(struct net_device netdev, struct netdev_bpf xdp)
		switch (xdp->command) {
		case XDP_SETUP_PROG:
		return nicvf_xdp_setup(nic, xdp->prog);
		case XDP_QUERY_PROG:
		xdp->prog_id = nic->xdp_prog ? nic->xdp_prog->aux->id : 0;
		return 0;
		default:
		return -EINVAL;
		}

drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c

+0 −5

Original line number	Diff line number	Diff line
		@@ -2077,14 +2077,9 @@ static int setup_xdp(struct net_device dev, struct bpf_prog prog)

		static int dpaa2_eth_xdp(struct net_device dev, struct netdev_bpf xdp)
		{
		struct dpaa2_eth_priv *priv = netdev_priv(dev);

		switch (xdp->command) {
		case XDP_SETUP_PROG:
		return setup_xdp(dev, xdp->prog);
		case XDP_QUERY_PROG:
		xdp->prog_id = priv->xdp_prog ? priv->xdp_prog->aux->id : 0;
		break;
		default:
		return -EINVAL;
		}

drivers/net/ethernet/intel/i40e/i40e_main.c

+0 −3

Original line number	Diff line number	Diff line
		@@ -12923,9 +12923,6 @@ static int i40e_xdp(struct net_device *dev,
		switch (xdp->command) {
		case XDP_SETUP_PROG:
		return i40e_xdp_setup(vsi, xdp->prog);
		case XDP_QUERY_PROG:
		xdp->prog_id = vsi->xdp_prog ? vsi->xdp_prog->aux->id : 0;
		return 0;
		case XDP_SETUP_XSK_UMEM:
		return i40e_xsk_umem_setup(vsi, xdp->xsk.umem,
		xdp->xsk.queue_id);