1 // SPDX-License-Identifier: GPL-2.0
2 /* XDP sockets monitoring support
3 *
4 * Copyright(c) 2019 Intel Corporation.
5 *
6 * Author: Björn Töpel <bjorn.topel@intel.com>
7 */
8
9 #include <linux/module.h>
10 #include <net/xdp_sock.h>
11 #include <linux/xdp_diag.h>
12 #include <linux/sock_diag.h>
13
14 #include "xsk_queue.h"
15 #include "xsk.h"
16
17 static int xsk_diag_put_info(const struct xdp_sock *xs, struct sk_buff *nlskb)
18 {
19 struct xdp_diag_info di = {};
20
21 di.ifindex = xs->dev ? xs->dev->ifindex : 0;
22 di.queue_id = xs->queue_id;
23 return nla_put(nlskb, XDP_DIAG_INFO, sizeof(di), &di);
24 }
25
26 static int xsk_diag_put_ring(const struct xsk_queue *queue, int nl_type,
27 struct sk_buff *nlskb)
28 {
29 struct xdp_diag_ring dr = {};
30
31 dr.entries = queue->nentries;
32 return nla_put(nlskb, nl_type, sizeof(dr), &dr);
33 }
34
35 static int xsk_diag_put_rings_cfg(const struct xdp_sock *xs,
36 struct sk_buff *nlskb)
37 {
38 int err = 0;
39
40 if (xs->rx)
41 err = xsk_diag_put_ring(xs->rx, XDP_DIAG_RX_RING, nlskb);
42 if (!err && xs->tx)
43 err = xsk_diag_put_ring(xs->tx, XDP_DIAG_TX_RING, nlskb);
44 return err;
45 }
46
47 static int xsk_diag_put_umem(const struct xdp_sock *xs, struct sk_buff *nlskb)
48 {
49 struct xsk_buff_pool *pool = xs->pool;
50 struct xdp_umem *umem = xs->umem;
51 struct xdp_diag_umem du = {};
52 int err;
53
54 if (!umem)
55 return 0;
56
57 du.id = umem->id;
58 du.size = umem->size;
59 du.num_pages = umem->npgs;
60 du.chunk_size = umem->chunk_size;
61 du.headroom = umem->headroom;
62 du.ifindex = (pool && pool->netdev) ? pool->netdev->ifindex : 0;
63 du.queue_id = pool ? pool->queue_id : 0;
64 du.flags = 0;
65 if (umem->zc)
66 du.flags |= XDP_DU_F_ZEROCOPY;
67 du.refs = refcount_read(&umem->users);
68
69 err = nla_put(nlskb, XDP_DIAG_UMEM, sizeof(du), &du);
70 if (!err && pool && pool->fq)
71 err = xsk_diag_put_ring(pool->fq,
72 XDP_DIAG_UMEM_FILL_RING, nlskb);
73 if (!err && pool && pool->cq)
74 err = xsk_diag_put_ring(pool->cq,
75 XDP_DIAG_UMEM_COMPLETION_RING, nlskb);
76 return err;
77 }
78
79 static int xsk_diag_put_stats(const struct xdp_sock *xs, struct sk_buff *nlskb)
80 {
81 struct xdp_diag_stats du = {};
82
83 du.n_rx_dropped = xs->rx_dropped;
84 du.n_rx_invalid = xskq_nb_invalid_descs(xs->rx);
85 du.n_rx_full = xs->rx_queue_full;
86 du.n_fill_ring_empty = xs->pool ? xskq_nb_queue_empty_descs(xs->pool->fq) : 0;
87 du.n_tx_invalid = xskq_nb_invalid_descs(xs->tx);
88 du.n_tx_ring_empty = xskq_nb_queue_empty_descs(xs->tx);
89 return nla_put(nlskb, XDP_DIAG_STATS, sizeof(du), &du);
90 }
91
92 static int xsk_diag_fill(struct sock *sk, struct sk_buff *nlskb,
93 struct xdp_diag_req *req,
94 struct user_namespace *user_ns,
95 u32 portid, u32 seq, u32 flags, int sk_ino)
96 {
97 struct xdp_sock *xs = xdp_sk(sk);
98 struct xdp_diag_msg *msg;
99 struct nlmsghdr *nlh;
100
101 nlh = nlmsg_put(nlskb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*msg),
102 flags);
103 if (!nlh)
104 return -EMSGSIZE;
105
106 msg = nlmsg_data(nlh);
107 memset(msg, 0, sizeof(*msg));
108 msg->xdiag_family = AF_XDP;
109 msg->xdiag_type = sk->sk_type;
110 msg->xdiag_ino = sk_ino;
111 sock_diag_save_cookie(sk, msg->xdiag_cookie);
112
113 mutex_lock(&xs->mutex);
114 if (READ_ONCE(xs->state) == XSK_UNBOUND)
115 goto out_nlmsg_trim;
116
117 if ((req->xdiag_show & XDP_SHOW_INFO) && xsk_diag_put_info(xs, nlskb))
118 goto out_nlmsg_trim;
119
120 if ((req->xdiag_show & XDP_SHOW_INFO) &&
121 nla_put_u32(nlskb, XDP_DIAG_UID,
122 from_kuid_munged(user_ns, sock_i_uid(sk))))
123 goto out_nlmsg_trim;
124
125 if ((req->xdiag_show & XDP_SHOW_RING_CFG) &&
126 xsk_diag_put_rings_cfg(xs, nlskb))
127 goto out_nlmsg_trim;
128
129 if ((req->xdiag_show & XDP_SHOW_UMEM) &&
130 xsk_diag_put_umem(xs, nlskb))
131 goto out_nlmsg_trim;
132
133 if ((req->xdiag_show & XDP_SHOW_MEMINFO) &&
134 sock_diag_put_meminfo(sk, nlskb, XDP_DIAG_MEMINFO))
135 goto out_nlmsg_trim;
136
137 if ((req->xdiag_show & XDP_SHOW_STATS) &&
138 xsk_diag_put_stats(xs, nlskb))
139 goto out_nlmsg_trim;
140
141 mutex_unlock(&xs->mutex);
142 nlmsg_end(nlskb, nlh);
143 return 0;
144
145 out_nlmsg_trim:
146 mutex_unlock(&xs->mutex);
147 nlmsg_cancel(nlskb, nlh);
148 return -EMSGSIZE;
149 }
150
151 static int xsk_diag_dump(struct sk_buff *nlskb, struct netlink_callback *cb)
152 {
153 struct xdp_diag_req *req = nlmsg_data(cb->nlh);
154 struct net *net = sock_net(nlskb->sk);
155 int num = 0, s_num = cb->args[0];
156 struct sock *sk;
157
158 mutex_lock(&net->xdp.lock);
159
160 sk_for_each(sk, &net->xdp.list) {
161 if (!net_eq(sock_net(sk), net))
162 continue;
163 if (num++ < s_num)
164 continue;
165
166 if (xsk_diag_fill(sk, nlskb, req,
167 sk_user_ns(NETLINK_CB(cb->skb).sk),
168 NETLINK_CB(cb->skb).portid,
169 cb->nlh->nlmsg_seq, NLM_F_MULTI,
170 sock_i_ino(sk)) < 0) {
171 num--;
172 break;
173 }
174 }
175
176 mutex_unlock(&net->xdp.lock);
177 cb->args[0] = num;
178 return nlskb->len;
179 }
180
181 static int xsk_diag_handler_dump(struct sk_buff *nlskb, struct nlmsghdr *hdr)
182 {
183 struct netlink_dump_control c = { .dump = xsk_diag_dump };
184 int hdrlen = sizeof(struct xdp_diag_req);
185 struct net *net = sock_net(nlskb->sk);
186
187 if (nlmsg_len(hdr) < hdrlen)
188 return -EINVAL;
189
190 if (!(hdr->nlmsg_flags & NLM_F_DUMP))
191 return -EOPNOTSUPP;
192
193 return netlink_dump_start(net->diag_nlsk, nlskb, hdr, &c);
194 }
195
196 static const struct sock_diag_handler xsk_diag_handler = {
197 .owner = THIS_MODULE,
198 .family = AF_XDP,
199 .dump = xsk_diag_handler_dump,
200 };
201
202 static int __init xsk_diag_init(void)
203 {
204 return sock_diag_register(&xsk_diag_handler);
205 }
206
207 static void __exit xsk_diag_exit(void)
208 {
209 sock_diag_unregister(&xsk_diag_handler);
210 }
211
212 module_init(xsk_diag_init);
213 module_exit(xsk_diag_exit);
214 MODULE_LICENSE("GPL");
215 MODULE_DESCRIPTION("XDP socket monitoring via SOCK_DIAG");
216 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, AF_XDP);
217
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