diff options
Diffstat (limited to 'drivers/net/hyperv/netvsc_bpf.c')
| -rw-r--r-- | drivers/net/hyperv/netvsc_bpf.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/drivers/net/hyperv/netvsc_bpf.c b/drivers/net/hyperv/netvsc_bpf.c new file mode 100644 index 000000000000..20adfe544294 --- /dev/null +++ b/drivers/net/hyperv/netvsc_bpf.c @@ -0,0 +1,209 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2019, Microsoft Corporation. + * + * Author: + * Haiyang Zhang <haiyangz@microsoft.com> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/ethtool.h> +#include <linux/bpf.h> +#include <linux/bpf_trace.h> +#include <linux/kernel.h> +#include <net/xdp.h> + +#include <linux/mutex.h> +#include <linux/rtnetlink.h> + +#include "hyperv_net.h" + +u32 netvsc_run_xdp(struct net_device *ndev, struct netvsc_channel *nvchan, + struct xdp_buff *xdp) +{ + void *data = nvchan->rsc.data[0]; + u32 len = nvchan->rsc.len[0]; + struct page *page = NULL; + struct bpf_prog *prog; + u32 act = XDP_PASS; + + xdp->data_hard_start = NULL; + + rcu_read_lock(); + prog = rcu_dereference(nvchan->bpf_prog); + + if (!prog) + goto out; + + /* allocate page buffer for data */ + page = alloc_page(GFP_ATOMIC); + if (!page) { + act = XDP_DROP; + goto out; + } + + xdp->data_hard_start = page_address(page); + xdp->data = xdp->data_hard_start + NETVSC_XDP_HDRM; + xdp_set_data_meta_invalid(xdp); + xdp->data_end = xdp->data + len; + xdp->rxq = &nvchan->xdp_rxq; + xdp->handle = 0; + + memcpy(xdp->data, data, len); + + 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(act); + } + +out: + rcu_read_unlock(); + + if (page && act != XDP_PASS && act != XDP_TX) { + __free_page(page); + xdp->data_hard_start = NULL; + } + + return act; +} + +unsigned int netvsc_xdp_fraglen(unsigned int len) +{ + return SKB_DATA_ALIGN(len) + + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); +} + +struct bpf_prog *netvsc_xdp_get(struct netvsc_device *nvdev) +{ + return rtnl_dereference(nvdev->chan_table[0].bpf_prog); +} + +int netvsc_xdp_set(struct net_device *dev, struct bpf_prog *prog, + struct netlink_ext_ack *extack, + struct netvsc_device *nvdev) +{ + struct bpf_prog *old_prog; + int buf_max, i; + + old_prog = netvsc_xdp_get(nvdev); + + if (!old_prog && !prog) + return 0; + + buf_max = NETVSC_XDP_HDRM + netvsc_xdp_fraglen(dev->mtu + ETH_HLEN); + if (prog && buf_max > PAGE_SIZE) { + netdev_err(dev, "XDP: mtu:%u too large, buf_max:%u\n", + dev->mtu, buf_max); + NL_SET_ERR_MSG_MOD(extack, "XDP: mtu too large"); + + return -EOPNOTSUPP; + } + + if (prog && (dev->features & NETIF_F_LRO)) { + netdev_err(dev, "XDP: not support LRO\n"); + NL_SET_ERR_MSG_MOD(extack, "XDP: not support LRO"); + + return -EOPNOTSUPP; + } + + if (prog) + bpf_prog_add(prog, nvdev->num_chn); + + for (i = 0; i < nvdev->num_chn; i++) + rcu_assign_pointer(nvdev->chan_table[i].bpf_prog, prog); + + if (old_prog) + for (i = 0; i < nvdev->num_chn; i++) + bpf_prog_put(old_prog); + + return 0; +} + +int netvsc_vf_setxdp(struct net_device *vf_netdev, struct bpf_prog *prog) +{ + struct netdev_bpf xdp; + bpf_op_t ndo_bpf; + + ASSERT_RTNL(); + + if (!vf_netdev) + return 0; + + ndo_bpf = vf_netdev->netdev_ops->ndo_bpf; + if (!ndo_bpf) + return 0; + + memset(&xdp, 0, sizeof(xdp)); + + xdp.command = XDP_SETUP_PROG; + xdp.prog = prog; + + return ndo_bpf(vf_netdev, &xdp); +} + +static u32 netvsc_xdp_query(struct netvsc_device *nvdev) +{ + struct bpf_prog *prog = netvsc_xdp_get(nvdev); + + if (prog) + return prog->aux->id; + + return 0; +} + +int netvsc_bpf(struct net_device *dev, struct netdev_bpf *bpf) +{ + struct net_device_context *ndevctx = netdev_priv(dev); + struct netvsc_device *nvdev = rtnl_dereference(ndevctx->nvdev); + struct net_device *vf_netdev = rtnl_dereference(ndevctx->vf_netdev); + struct netlink_ext_ack *extack = bpf->extack; + int ret; + + if (!nvdev || nvdev->destroy) { + if (bpf->command == XDP_QUERY_PROG) { + bpf->prog_id = 0; + return 0; /* Query must always succeed */ + } else { + return -ENODEV; + } + } + + switch (bpf->command) { + case XDP_SETUP_PROG: + ret = netvsc_xdp_set(dev, bpf->prog, extack, nvdev); + + if (ret) + return ret; + + ret = netvsc_vf_setxdp(vf_netdev, bpf->prog); + + if (ret) { + netdev_err(dev, "vf_setxdp failed:%d\n", ret); + NL_SET_ERR_MSG_MOD(extack, "vf_setxdp failed"); + + netvsc_xdp_set(dev, NULL, extack, nvdev); + } + + return ret; + + case XDP_QUERY_PROG: + bpf->prog_id = netvsc_xdp_query(nvdev); + return 0; + + default: + return -EINVAL; + } +} |