interconnect: qcom: icc-rpm: Fix peak rate calculation
[linux-2.6-microblaze.git] / net / unix / unix_bpf.c
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2021 Cong Wang <cong.wang@bytedance.com> */
3
4 #include <linux/skmsg.h>
5 #include <linux/bpf.h>
6 #include <net/sock.h>
7 #include <net/af_unix.h>
8
9 #define unix_sk_has_data(__sk, __psock)                                 \
10                 ({      !skb_queue_empty(&__sk->sk_receive_queue) ||    \
11                         !skb_queue_empty(&__psock->ingress_skb) ||      \
12                         !list_empty(&__psock->ingress_msg);             \
13                 })
14
15 static int unix_msg_wait_data(struct sock *sk, struct sk_psock *psock,
16                               long timeo)
17 {
18         DEFINE_WAIT_FUNC(wait, woken_wake_function);
19         struct unix_sock *u = unix_sk(sk);
20         int ret = 0;
21
22         if (sk->sk_shutdown & RCV_SHUTDOWN)
23                 return 1;
24
25         if (!timeo)
26                 return ret;
27
28         add_wait_queue(sk_sleep(sk), &wait);
29         sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
30         if (!unix_sk_has_data(sk, psock)) {
31                 mutex_unlock(&u->iolock);
32                 wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
33                 mutex_lock(&u->iolock);
34                 ret = unix_sk_has_data(sk, psock);
35         }
36         sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
37         remove_wait_queue(sk_sleep(sk), &wait);
38         return ret;
39 }
40
41 static int __unix_recvmsg(struct sock *sk, struct msghdr *msg,
42                           size_t len, int flags)
43 {
44         if (sk->sk_type == SOCK_DGRAM)
45                 return __unix_dgram_recvmsg(sk, msg, len, flags);
46         else
47                 return __unix_stream_recvmsg(sk, msg, len, flags);
48 }
49
50 static int unix_bpf_recvmsg(struct sock *sk, struct msghdr *msg,
51                             size_t len, int flags, int *addr_len)
52 {
53         struct unix_sock *u = unix_sk(sk);
54         struct sk_psock *psock;
55         int copied;
56
57         if (!len)
58                 return 0;
59
60         psock = sk_psock_get(sk);
61         if (unlikely(!psock))
62                 return __unix_recvmsg(sk, msg, len, flags);
63
64         mutex_lock(&u->iolock);
65         if (!skb_queue_empty(&sk->sk_receive_queue) &&
66             sk_psock_queue_empty(psock)) {
67                 mutex_unlock(&u->iolock);
68                 sk_psock_put(sk, psock);
69                 return __unix_recvmsg(sk, msg, len, flags);
70         }
71
72 msg_bytes_ready:
73         copied = sk_msg_recvmsg(sk, psock, msg, len, flags);
74         if (!copied) {
75                 long timeo;
76                 int data;
77
78                 timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
79                 data = unix_msg_wait_data(sk, psock, timeo);
80                 if (data) {
81                         if (!sk_psock_queue_empty(psock))
82                                 goto msg_bytes_ready;
83                         mutex_unlock(&u->iolock);
84                         sk_psock_put(sk, psock);
85                         return __unix_recvmsg(sk, msg, len, flags);
86                 }
87                 copied = -EAGAIN;
88         }
89         mutex_unlock(&u->iolock);
90         sk_psock_put(sk, psock);
91         return copied;
92 }
93
94 static struct proto *unix_dgram_prot_saved __read_mostly;
95 static DEFINE_SPINLOCK(unix_dgram_prot_lock);
96 static struct proto unix_dgram_bpf_prot;
97
98 static struct proto *unix_stream_prot_saved __read_mostly;
99 static DEFINE_SPINLOCK(unix_stream_prot_lock);
100 static struct proto unix_stream_bpf_prot;
101
102 static void unix_dgram_bpf_rebuild_protos(struct proto *prot, const struct proto *base)
103 {
104         *prot        = *base;
105         prot->close  = sock_map_close;
106         prot->recvmsg = unix_bpf_recvmsg;
107         prot->sock_is_readable = sk_msg_is_readable;
108 }
109
110 static void unix_stream_bpf_rebuild_protos(struct proto *prot,
111                                            const struct proto *base)
112 {
113         *prot        = *base;
114         prot->close  = sock_map_close;
115         prot->recvmsg = unix_bpf_recvmsg;
116         prot->sock_is_readable = sk_msg_is_readable;
117         prot->unhash  = sock_map_unhash;
118 }
119
120 static void unix_dgram_bpf_check_needs_rebuild(struct proto *ops)
121 {
122         if (unlikely(ops != smp_load_acquire(&unix_dgram_prot_saved))) {
123                 spin_lock_bh(&unix_dgram_prot_lock);
124                 if (likely(ops != unix_dgram_prot_saved)) {
125                         unix_dgram_bpf_rebuild_protos(&unix_dgram_bpf_prot, ops);
126                         smp_store_release(&unix_dgram_prot_saved, ops);
127                 }
128                 spin_unlock_bh(&unix_dgram_prot_lock);
129         }
130 }
131
132 static void unix_stream_bpf_check_needs_rebuild(struct proto *ops)
133 {
134         if (unlikely(ops != smp_load_acquire(&unix_stream_prot_saved))) {
135                 spin_lock_bh(&unix_stream_prot_lock);
136                 if (likely(ops != unix_stream_prot_saved)) {
137                         unix_stream_bpf_rebuild_protos(&unix_stream_bpf_prot, ops);
138                         smp_store_release(&unix_stream_prot_saved, ops);
139                 }
140                 spin_unlock_bh(&unix_stream_prot_lock);
141         }
142 }
143
144 int unix_dgram_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore)
145 {
146         if (sk->sk_type != SOCK_DGRAM)
147                 return -EOPNOTSUPP;
148
149         if (restore) {
150                 sk->sk_write_space = psock->saved_write_space;
151                 sock_replace_proto(sk, psock->sk_proto);
152                 return 0;
153         }
154
155         unix_dgram_bpf_check_needs_rebuild(psock->sk_proto);
156         sock_replace_proto(sk, &unix_dgram_bpf_prot);
157         return 0;
158 }
159
160 int unix_stream_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore)
161 {
162         if (restore) {
163                 sk->sk_write_space = psock->saved_write_space;
164                 sock_replace_proto(sk, psock->sk_proto);
165                 return 0;
166         }
167
168         unix_stream_bpf_check_needs_rebuild(psock->sk_proto);
169         sock_replace_proto(sk, &unix_stream_bpf_prot);
170         return 0;
171 }
172
173 void __init unix_bpf_build_proto(void)
174 {
175         unix_dgram_bpf_rebuild_protos(&unix_dgram_bpf_prot, &unix_dgram_proto);
176         unix_stream_bpf_rebuild_protos(&unix_stream_bpf_prot, &unix_stream_proto);
177
178 }