1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
// 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;
/* Ensure that the below memcpy() won't overflow the page buffer. */
if (len > ndev->mtu + ETH_HLEN) {
act = XDP_DROP;
goto out;
}
/* allocate page buffer for data */
page = alloc_page(GFP_ATOMIC);
if (!page) {
act = XDP_DROP;
goto out;
}
xdp_init_buff(xdp, PAGE_SIZE, &nvchan->xdp_rxq);
xdp_prepare_buff(xdp, page_address(page), NETVSC_XDP_HDRM, len, false);
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 - 1);
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;
int ret;
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));
if (prog)
bpf_prog_inc(prog);
xdp.command = XDP_SETUP_PROG;
xdp.prog = prog;
ret = ndo_bpf(vf_netdev, &xdp);
if (ret && prog)
bpf_prog_put(prog);
return ret;
}
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) {
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;
default:
return -EINVAL;
}
}
|
