xref: /openbmc/linux/include/net/kcm.h (revision 7587eb18)
1 /*
2  * Kernel Connection Multiplexor
3  *
4  * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2
8  * as published by the Free Software Foundation.
9  */
10 
11 #ifndef __NET_KCM_H_
12 #define __NET_KCM_H_
13 
14 #include <linux/skbuff.h>
15 #include <net/sock.h>
16 #include <uapi/linux/kcm.h>
17 
18 extern unsigned int kcm_net_id;
19 
20 #define KCM_STATS_ADD(stat, count) ((stat) += (count))
21 #define KCM_STATS_INCR(stat) ((stat)++)
22 
23 struct kcm_psock_stats {
24 	unsigned long long rx_msgs;
25 	unsigned long long rx_bytes;
26 	unsigned long long tx_msgs;
27 	unsigned long long tx_bytes;
28 	unsigned int rx_aborts;
29 	unsigned int rx_mem_fail;
30 	unsigned int rx_need_more_hdr;
31 	unsigned int rx_msg_too_big;
32 	unsigned int rx_msg_timeouts;
33 	unsigned int rx_bad_hdr_len;
34 	unsigned long long reserved;
35 	unsigned long long unreserved;
36 	unsigned int tx_aborts;
37 };
38 
39 struct kcm_mux_stats {
40 	unsigned long long rx_msgs;
41 	unsigned long long rx_bytes;
42 	unsigned long long tx_msgs;
43 	unsigned long long tx_bytes;
44 	unsigned int rx_ready_drops;
45 	unsigned int tx_retries;
46 	unsigned int psock_attach;
47 	unsigned int psock_unattach_rsvd;
48 	unsigned int psock_unattach;
49 };
50 
51 struct kcm_stats {
52 	unsigned long long rx_msgs;
53 	unsigned long long rx_bytes;
54 	unsigned long long tx_msgs;
55 	unsigned long long tx_bytes;
56 };
57 
58 struct kcm_tx_msg {
59 	unsigned int sent;
60 	unsigned int fragidx;
61 	unsigned int frag_offset;
62 	unsigned int msg_flags;
63 	struct sk_buff *frag_skb;
64 	struct sk_buff *last_skb;
65 };
66 
67 struct kcm_rx_msg {
68 	int full_len;
69 	int accum_len;
70 	int offset;
71 	int early_eaten;
72 };
73 
74 /* Socket structure for KCM client sockets */
75 struct kcm_sock {
76 	struct sock sk;
77 	struct kcm_mux *mux;
78 	struct list_head kcm_sock_list;
79 	int index;
80 	u32 done : 1;
81 	struct work_struct done_work;
82 
83 	struct kcm_stats stats;
84 
85 	/* Transmit */
86 	struct kcm_psock *tx_psock;
87 	struct work_struct tx_work;
88 	struct list_head wait_psock_list;
89 	struct sk_buff *seq_skb;
90 
91 	/* Don't use bit fields here, these are set under different locks */
92 	bool tx_wait;
93 	bool tx_wait_more;
94 
95 	/* Receive */
96 	struct kcm_psock *rx_psock;
97 	struct list_head wait_rx_list; /* KCMs waiting for receiving */
98 	bool rx_wait;
99 	u32 rx_disabled : 1;
100 };
101 
102 struct bpf_prog;
103 
104 /* Structure for an attached lower socket */
105 struct kcm_psock {
106 	struct sock *sk;
107 	struct kcm_mux *mux;
108 	int index;
109 
110 	u32 tx_stopped : 1;
111 	u32 rx_stopped : 1;
112 	u32 done : 1;
113 	u32 unattaching : 1;
114 
115 	void (*save_state_change)(struct sock *sk);
116 	void (*save_data_ready)(struct sock *sk);
117 	void (*save_write_space)(struct sock *sk);
118 
119 	struct list_head psock_list;
120 
121 	struct kcm_psock_stats stats;
122 
123 	/* Receive */
124 	struct sk_buff *rx_skb_head;
125 	struct sk_buff **rx_skb_nextp;
126 	struct sk_buff *ready_rx_msg;
127 	struct list_head psock_ready_list;
128 	struct work_struct rx_work;
129 	struct delayed_work rx_delayed_work;
130 	struct bpf_prog *bpf_prog;
131 	struct kcm_sock *rx_kcm;
132 	unsigned long long saved_rx_bytes;
133 	unsigned long long saved_rx_msgs;
134 	struct timer_list rx_msg_timer;
135 	unsigned int rx_need_bytes;
136 
137 	/* Transmit */
138 	struct kcm_sock *tx_kcm;
139 	struct list_head psock_avail_list;
140 	unsigned long long saved_tx_bytes;
141 	unsigned long long saved_tx_msgs;
142 };
143 
144 /* Per net MUX list */
145 struct kcm_net {
146 	struct mutex mutex;
147 	struct kcm_psock_stats aggregate_psock_stats;
148 	struct kcm_mux_stats aggregate_mux_stats;
149 	struct list_head mux_list;
150 	int count;
151 };
152 
153 /* Structure for a MUX */
154 struct kcm_mux {
155 	struct list_head kcm_mux_list;
156 	struct rcu_head rcu;
157 	struct kcm_net *knet;
158 
159 	struct list_head kcm_socks;	/* All KCM sockets on MUX */
160 	int kcm_socks_cnt;		/* Total KCM socket count for MUX */
161 	struct list_head psocks;	/* List of all psocks on MUX */
162 	int psocks_cnt;		/* Total attached sockets */
163 
164 	struct kcm_mux_stats stats;
165 	struct kcm_psock_stats aggregate_psock_stats;
166 
167 	/* Receive */
168 	spinlock_t rx_lock ____cacheline_aligned_in_smp;
169 	struct list_head kcm_rx_waiters; /* KCMs waiting for receiving */
170 	struct list_head psocks_ready;	/* List of psocks with a msg ready */
171 	struct sk_buff_head rx_hold_queue;
172 
173 	/* Transmit */
174 	spinlock_t  lock ____cacheline_aligned_in_smp;	/* TX and mux locking */
175 	struct list_head psocks_avail;	/* List of available psocks */
176 	struct list_head kcm_tx_waiters; /* KCMs waiting for a TX psock */
177 };
178 
179 #ifdef CONFIG_PROC_FS
180 int kcm_proc_init(void);
181 void kcm_proc_exit(void);
182 #else
183 static inline int kcm_proc_init(void) { return 0; }
184 static inline void kcm_proc_exit(void) { }
185 #endif
186 
187 static inline void aggregate_psock_stats(struct kcm_psock_stats *stats,
188 					 struct kcm_psock_stats *agg_stats)
189 {
190 	/* Save psock statistics in the mux when psock is being unattached. */
191 
192 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
193 	SAVE_PSOCK_STATS(rx_msgs);
194 	SAVE_PSOCK_STATS(rx_bytes);
195 	SAVE_PSOCK_STATS(rx_aborts);
196 	SAVE_PSOCK_STATS(rx_mem_fail);
197 	SAVE_PSOCK_STATS(rx_need_more_hdr);
198 	SAVE_PSOCK_STATS(rx_msg_too_big);
199 	SAVE_PSOCK_STATS(rx_msg_timeouts);
200 	SAVE_PSOCK_STATS(rx_bad_hdr_len);
201 	SAVE_PSOCK_STATS(tx_msgs);
202 	SAVE_PSOCK_STATS(tx_bytes);
203 	SAVE_PSOCK_STATS(reserved);
204 	SAVE_PSOCK_STATS(unreserved);
205 	SAVE_PSOCK_STATS(tx_aborts);
206 #undef SAVE_PSOCK_STATS
207 }
208 
209 static inline void aggregate_mux_stats(struct kcm_mux_stats *stats,
210 				       struct kcm_mux_stats *agg_stats)
211 {
212 	/* Save psock statistics in the mux when psock is being unattached. */
213 
214 #define SAVE_MUX_STATS(_stat) (agg_stats->_stat += stats->_stat)
215 	SAVE_MUX_STATS(rx_msgs);
216 	SAVE_MUX_STATS(rx_bytes);
217 	SAVE_MUX_STATS(tx_msgs);
218 	SAVE_MUX_STATS(tx_bytes);
219 	SAVE_MUX_STATS(rx_ready_drops);
220 	SAVE_MUX_STATS(psock_attach);
221 	SAVE_MUX_STATS(psock_unattach_rsvd);
222 	SAVE_MUX_STATS(psock_unattach);
223 #undef SAVE_MUX_STATS
224 }
225 
226 #endif /* __NET_KCM_H_ */
227