xref: /openbmc/linux/include/net/kcm.h (revision 193b1fc1)
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 frag_offset;
51 	unsigned int msg_flags;
52 	bool started_tx;
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 	struct mutex tx_mutex;
74 	u32 tx_stopped : 1;
75 
76 	/* Don't use bit fields here, these are set under different locks */
77 	bool tx_wait;
78 	bool tx_wait_more;
79 
80 	/* Receive */
81 	struct kcm_psock *rx_psock;
82 	struct list_head wait_rx_list; /* KCMs waiting for receiving */
83 	bool rx_wait;
84 	u32 rx_disabled : 1;
85 };
86 
87 struct bpf_prog;
88 
89 /* Structure for an attached lower socket */
90 struct kcm_psock {
91 	struct sock *sk;
92 	struct strparser strp;
93 	struct kcm_mux *mux;
94 	int index;
95 
96 	u32 tx_stopped : 1;
97 	u32 done : 1;
98 	u32 unattaching : 1;
99 
100 	void (*save_state_change)(struct sock *sk);
101 	void (*save_data_ready)(struct sock *sk);
102 	void (*save_write_space)(struct sock *sk);
103 
104 	struct list_head psock_list;
105 
106 	struct kcm_psock_stats stats;
107 
108 	/* Receive */
109 	struct list_head psock_ready_list;
110 	struct bpf_prog *bpf_prog;
111 	struct kcm_sock *rx_kcm;
112 	unsigned long long saved_rx_bytes;
113 	unsigned long long saved_rx_msgs;
114 	struct sk_buff *ready_rx_msg;
115 
116 	/* Transmit */
117 	struct kcm_sock *tx_kcm;
118 	struct list_head psock_avail_list;
119 	unsigned long long saved_tx_bytes;
120 	unsigned long long saved_tx_msgs;
121 };
122 
123 /* Per net MUX list */
124 struct kcm_net {
125 	struct mutex mutex;
126 	struct kcm_psock_stats aggregate_psock_stats;
127 	struct kcm_mux_stats aggregate_mux_stats;
128 	struct strp_aggr_stats aggregate_strp_stats;
129 	struct list_head mux_list;
130 	int count;
131 };
132 
133 /* Structure for a MUX */
134 struct kcm_mux {
135 	struct list_head kcm_mux_list;
136 	struct rcu_head rcu;
137 	struct kcm_net *knet;
138 
139 	struct list_head kcm_socks;	/* All KCM sockets on MUX */
140 	int kcm_socks_cnt;		/* Total KCM socket count for MUX */
141 	struct list_head psocks;	/* List of all psocks on MUX */
142 	int psocks_cnt;		/* Total attached sockets */
143 
144 	struct kcm_mux_stats stats;
145 	struct kcm_psock_stats aggregate_psock_stats;
146 	struct strp_aggr_stats aggregate_strp_stats;
147 
148 	/* Receive */
149 	spinlock_t rx_lock ____cacheline_aligned_in_smp;
150 	struct list_head kcm_rx_waiters; /* KCMs waiting for receiving */
151 	struct list_head psocks_ready;	/* List of psocks with a msg ready */
152 	struct sk_buff_head rx_hold_queue;
153 
154 	/* Transmit */
155 	spinlock_t  lock ____cacheline_aligned_in_smp;	/* TX and mux locking */
156 	struct list_head psocks_avail;	/* List of available psocks */
157 	struct list_head kcm_tx_waiters; /* KCMs waiting for a TX psock */
158 };
159 
160 #ifdef CONFIG_PROC_FS
161 int kcm_proc_init(void);
162 void kcm_proc_exit(void);
163 #else
164 static inline int kcm_proc_init(void) { return 0; }
165 static inline void kcm_proc_exit(void) { }
166 #endif
167 
168 static inline void aggregate_psock_stats(struct kcm_psock_stats *stats,
169 					 struct kcm_psock_stats *agg_stats)
170 {
171 	/* Save psock statistics in the mux when psock is being unattached. */
172 
173 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
174 	SAVE_PSOCK_STATS(tx_msgs);
175 	SAVE_PSOCK_STATS(tx_bytes);
176 	SAVE_PSOCK_STATS(reserved);
177 	SAVE_PSOCK_STATS(unreserved);
178 	SAVE_PSOCK_STATS(tx_aborts);
179 #undef SAVE_PSOCK_STATS
180 }
181 
182 static inline void aggregate_mux_stats(struct kcm_mux_stats *stats,
183 				       struct kcm_mux_stats *agg_stats)
184 {
185 	/* Save psock statistics in the mux when psock is being unattached. */
186 
187 #define SAVE_MUX_STATS(_stat) (agg_stats->_stat += stats->_stat)
188 	SAVE_MUX_STATS(rx_msgs);
189 	SAVE_MUX_STATS(rx_bytes);
190 	SAVE_MUX_STATS(tx_msgs);
191 	SAVE_MUX_STATS(tx_bytes);
192 	SAVE_MUX_STATS(rx_ready_drops);
193 	SAVE_MUX_STATS(psock_attach);
194 	SAVE_MUX_STATS(psock_unattach_rsvd);
195 	SAVE_MUX_STATS(psock_unattach);
196 #undef SAVE_MUX_STATS
197 }
198 
199 #endif /* __NET_KCM_H_ */
200