linux/linux-5.18.11/drivers/net/ethernet/microsoft/mana/mana_bpf.c

163 lines
3.2 KiB
C

// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/* Copyright (c) 2021, Microsoft Corporation. */
#include <linux/inetdevice.h>
#include <linux/etherdevice.h>
#include <linux/mm.h>
#include <linux/bpf.h>
#include <linux/bpf_trace.h>
#include <net/xdp.h>
#include "mana.h"
void mana_xdp_tx(struct sk_buff *skb, struct net_device *ndev)
{
u16 txq_idx = skb_get_queue_mapping(skb);
struct netdev_queue *ndevtxq;
int rc;
__skb_push(skb, ETH_HLEN);
ndevtxq = netdev_get_tx_queue(ndev, txq_idx);
__netif_tx_lock(ndevtxq, smp_processor_id());
rc = mana_start_xmit(skb, ndev);
__netif_tx_unlock(ndevtxq);
if (dev_xmit_complete(rc))
return;
dev_kfree_skb_any(skb);
ndev->stats.tx_dropped++;
}
u32 mana_run_xdp(struct net_device *ndev, struct mana_rxq *rxq,
struct xdp_buff *xdp, void *buf_va, uint pkt_len)
{
struct bpf_prog *prog;
u32 act = XDP_PASS;
rcu_read_lock();
prog = rcu_dereference(rxq->bpf_prog);
if (!prog)
goto out;
xdp_init_buff(xdp, PAGE_SIZE, &rxq->xdp_rxq);
xdp_prepare_buff(xdp, buf_va, XDP_PACKET_HEADROOM, pkt_len, false);
act = bpf_prog_run_xdp(prog, xdp);
switch (act) {
case XDP_PASS:
case XDP_TX:
case XDP_DROP:
break;
case XDP_ABORTED:
trace_xdp_exception(ndev, prog, act);
break;
default:
bpf_warn_invalid_xdp_action(ndev, prog, act);
}
out:
rcu_read_unlock();
return act;
}
static unsigned int mana_xdp_fraglen(unsigned int len)
{
return SKB_DATA_ALIGN(len) +
SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
}
struct bpf_prog *mana_xdp_get(struct mana_port_context *apc)
{
ASSERT_RTNL();
return apc->bpf_prog;
}
static struct bpf_prog *mana_chn_xdp_get(struct mana_port_context *apc)
{
return rtnl_dereference(apc->rxqs[0]->bpf_prog);
}
/* Set xdp program on channels */
void mana_chn_setxdp(struct mana_port_context *apc, struct bpf_prog *prog)
{
struct bpf_prog *old_prog = mana_chn_xdp_get(apc);
unsigned int num_queues = apc->num_queues;
int i;
ASSERT_RTNL();
if (old_prog == prog)
return;
if (prog)
bpf_prog_add(prog, num_queues);
for (i = 0; i < num_queues; i++)
rcu_assign_pointer(apc->rxqs[i]->bpf_prog, prog);
if (old_prog)
for (i = 0; i < num_queues; i++)
bpf_prog_put(old_prog);
}
static int mana_xdp_set(struct net_device *ndev, struct bpf_prog *prog,
struct netlink_ext_ack *extack)
{
struct mana_port_context *apc = netdev_priv(ndev);
struct bpf_prog *old_prog;
int buf_max;
old_prog = mana_xdp_get(apc);
if (!old_prog && !prog)
return 0;
buf_max = XDP_PACKET_HEADROOM + mana_xdp_fraglen(ndev->mtu + ETH_HLEN);
if (prog && buf_max > PAGE_SIZE) {
netdev_err(ndev, "XDP: mtu:%u too large, buf_max:%u\n",
ndev->mtu, buf_max);
NL_SET_ERR_MSG_MOD(extack, "XDP: mtu too large");
return -EOPNOTSUPP;
}
/* One refcnt of the prog is hold by the caller already, so
* don't increase refcnt for this one.
*/
apc->bpf_prog = prog;
if (old_prog)
bpf_prog_put(old_prog);
if (apc->port_is_up)
mana_chn_setxdp(apc, prog);
return 0;
}
int mana_bpf(struct net_device *ndev, struct netdev_bpf *bpf)
{
struct netlink_ext_ack *extack = bpf->extack;
int ret;
switch (bpf->command) {
case XDP_SETUP_PROG:
return mana_xdp_set(ndev, bpf->prog, extack);
default:
return -EOPNOTSUPP;
}
return ret;
}