xref: /openbmc/linux/include/net/kcm.h (revision adb80490)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Kernel Connection Multiplexor
4  *
5  * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
6  */
7 
8 #ifndef __NET_KCM_H_
9 #define __NET_KCM_H_
10 
11 #include <linux/skbuff.h>
12 #include <net/sock.h>
13 #include <net/strparser.h>
14 #include <uapi/linux/kcm.h>
15 
16 extern unsigned int kcm_net_id;
17 
18 #define KCM_STATS_ADD(stat, count) ((stat) += (count))
19 #define KCM_STATS_INCR(stat) ((stat)++)
20 
21 struct kcm_psock_stats {
22 	unsigned long long tx_msgs;
23 	unsigned long long tx_bytes;
24 	unsigned long long reserved;
25 	unsigned long long unreserved;
26 	unsigned int tx_aborts;
27 };
28 
29 struct kcm_mux_stats {
30 	unsigned long long rx_msgs;
31 	unsigned long long rx_bytes;
32 	unsigned long long tx_msgs;
33 	unsigned long long tx_bytes;
34 	unsigned int rx_ready_drops;
35 	unsigned int tx_retries;
36 	unsigned int psock_attach;
37 	unsigned int psock_unattach_rsvd;
38 	unsigned int psock_unattach;
39 };
40 
41 struct kcm_stats {
42 	unsigned long long rx_msgs;
43 	unsigned long long rx_bytes;
44 	unsigned long long tx_msgs;
45 	unsigned long long tx_bytes;
46 };
47 
48 struct kcm_tx_msg {
49 	unsigned int sent;
50 	unsigned int fragidx;
51 	unsigned int frag_offset;
52 	unsigned int msg_flags;
53 	struct sk_buff *frag_skb;
54 	struct sk_buff *last_skb;
55 };
56 
57 /* Socket structure for KCM client sockets */
58 struct kcm_sock {
59 	struct sock sk;
60 	struct kcm_mux *mux;
61 	struct list_head kcm_sock_list;
62 	int index;
63 	u32 done : 1;
64 	struct work_struct done_work;
65 
66 	struct kcm_stats stats;
67 
68 	/* Transmit */
69 	struct kcm_psock *tx_psock;
70 	struct work_struct tx_work;
71 	struct list_head wait_psock_list;
72 	struct sk_buff *seq_skb;
73 	u32 tx_stopped : 1;
74 
75 	/* Don't use bit fields here, these are set under different locks */
76 	bool tx_wait;
77 	bool tx_wait_more;
78 
79 	/* Receive */
80 	struct kcm_psock *rx_psock;
81 	struct list_head wait_rx_list; /* KCMs waiting for receiving */
82 	bool rx_wait;
83 	u32 rx_disabled : 1;
84 };
85 
86 struct bpf_prog;
87 
88 /* Structure for an attached lower socket */
89 struct kcm_psock {
90 	struct sock *sk;
91 	struct strparser strp;
92 	struct kcm_mux *mux;
93 	int index;
94 
95 	u32 tx_stopped : 1;
96 	u32 done : 1;
97 	u32 unattaching : 1;
98 
99 	void (*save_state_change)(struct sock *sk);
100 	void (*save_data_ready)(struct sock *sk);
101 	void (*save_write_space)(struct sock *sk);
102 
103 	struct list_head psock_list;
104 
105 	struct kcm_psock_stats stats;
106 
107 	/* Receive */
108 	struct list_head psock_ready_list;
109 	struct bpf_prog *bpf_prog;
110 	struct kcm_sock *rx_kcm;
111 	unsigned long long saved_rx_bytes;
112 	unsigned long long saved_rx_msgs;
113 	struct sk_buff *ready_rx_msg;
114 
115 	/* Transmit */
116 	struct kcm_sock *tx_kcm;
117 	struct list_head psock_avail_list;
118 	unsigned long long saved_tx_bytes;
119 	unsigned long long saved_tx_msgs;
120 };
121 
122 /* Per net MUX list */
123 struct kcm_net {
124 	struct mutex mutex;
125 	struct kcm_psock_stats aggregate_psock_stats;
126 	struct kcm_mux_stats aggregate_mux_stats;
127 	struct strp_aggr_stats aggregate_strp_stats;
128 	struct list_head mux_list;
129 	int count;
130 };
131 
132 /* Structure for a MUX */
133 struct kcm_mux {
134 	struct list_head kcm_mux_list;
135 	struct rcu_head rcu;
136 	struct kcm_net *knet;
137 
138 	struct list_head kcm_socks;	/* All KCM sockets on MUX */
139 	int kcm_socks_cnt;		/* Total KCM socket count for MUX */
140 	struct list_head psocks;	/* List of all psocks on MUX */
141 	int psocks_cnt;		/* Total attached sockets */
142 
143 	struct kcm_mux_stats stats;
144 	struct kcm_psock_stats aggregate_psock_stats;
145 	struct strp_aggr_stats aggregate_strp_stats;
146 
147 	/* Receive */
148 	spinlock_t rx_lock ____cacheline_aligned_in_smp;
149 	struct list_head kcm_rx_waiters; /* KCMs waiting for receiving */
150 	struct list_head psocks_ready;	/* List of psocks with a msg ready */
151 	struct sk_buff_head rx_hold_queue;
152 
153 	/* Transmit */
154 	spinlock_t  lock ____cacheline_aligned_in_smp;	/* TX and mux locking */
155 	struct list_head psocks_avail;	/* List of available psocks */
156 	struct list_head kcm_tx_waiters; /* KCMs waiting for a TX psock */
157 };
158 
159 #ifdef CONFIG_PROC_FS
160 int kcm_proc_init(void);
161 void kcm_proc_exit(void);
162 #else
163 static inline int kcm_proc_init(void) { return 0; }
164 static inline void kcm_proc_exit(void) { }
165 #endif
166 
167 static inline void aggregate_psock_stats(struct kcm_psock_stats *stats,
168 					 struct kcm_psock_stats *agg_stats)
169 {
170 	/* Save psock statistics in the mux when psock is being unattached. */
171 
172 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
173 	SAVE_PSOCK_STATS(tx_msgs);
174 	SAVE_PSOCK_STATS(tx_bytes);
175 	SAVE_PSOCK_STATS(reserved);
176 	SAVE_PSOCK_STATS(unreserved);
177 	SAVE_PSOCK_STATS(tx_aborts);
178 #undef SAVE_PSOCK_STATS
179 }
180 
181 static inline void aggregate_mux_stats(struct kcm_mux_stats *stats,
182 				       struct kcm_mux_stats *agg_stats)
183 {
184 	/* Save psock statistics in the mux when psock is being unattached. */
185 
186 #define SAVE_MUX_STATS(_stat) (agg_stats->_stat += stats->_stat)
187 	SAVE_MUX_STATS(rx_msgs);
188 	SAVE_MUX_STATS(rx_bytes);
189 	SAVE_MUX_STATS(tx_msgs);
190 	SAVE_MUX_STATS(tx_bytes);
191 	SAVE_MUX_STATS(rx_ready_drops);
192 	SAVE_MUX_STATS(psock_attach);
193 	SAVE_MUX_STATS(psock_unattach_rsvd);
194 	SAVE_MUX_STATS(psock_unattach);
195 #undef SAVE_MUX_STATS
196 }
197 
198 #endif /* __NET_KCM_H_ */
199