xref: /openbmc/linux/include/net/strparser.h (revision be709d48)
1 /*
2  * Stream Parser
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_STRPARSER_H_
12 #define __NET_STRPARSER_H_
13 
14 #include <linux/skbuff.h>
15 #include <net/sock.h>
16 
17 #define STRP_STATS_ADD(stat, count) ((stat) += (count))
18 #define STRP_STATS_INCR(stat) ((stat)++)
19 
20 struct strp_stats {
21 	unsigned long long msgs;
22 	unsigned long long bytes;
23 	unsigned int mem_fail;
24 	unsigned int need_more_hdr;
25 	unsigned int msg_too_big;
26 	unsigned int msg_timeouts;
27 	unsigned int bad_hdr_len;
28 };
29 
30 struct strp_aggr_stats {
31 	unsigned long long msgs;
32 	unsigned long long bytes;
33 	unsigned int mem_fail;
34 	unsigned int need_more_hdr;
35 	unsigned int msg_too_big;
36 	unsigned int msg_timeouts;
37 	unsigned int bad_hdr_len;
38 	unsigned int aborts;
39 	unsigned int interrupted;
40 	unsigned int unrecov_intr;
41 };
42 
43 struct strparser;
44 
45 /* Callbacks are called with lock held for the attached socket */
46 struct strp_callbacks {
47 	int (*parse_msg)(struct strparser *strp, struct sk_buff *skb);
48 	void (*rcv_msg)(struct strparser *strp, struct sk_buff *skb);
49 	int (*read_sock_done)(struct strparser *strp, int err);
50 	void (*abort_parser)(struct strparser *strp, int err);
51 	void (*lock)(struct strparser *strp);
52 	void (*unlock)(struct strparser *strp);
53 };
54 
55 struct strp_msg {
56 	int full_len;
57 	int offset;
58 };
59 
60 static inline struct strp_msg *strp_msg(struct sk_buff *skb)
61 {
62 	return (struct strp_msg *)((void *)skb->cb +
63 		offsetof(struct qdisc_skb_cb, data));
64 }
65 
66 /* Structure for an attached lower socket */
67 struct strparser {
68 	struct sock *sk;
69 
70 	u32 stopped : 1;
71 	u32 paused : 1;
72 	u32 aborted : 1;
73 	u32 interrupted : 1;
74 	u32 unrecov_intr : 1;
75 
76 	struct sk_buff **skb_nextp;
77 	struct sk_buff *skb_head;
78 	unsigned int need_bytes;
79 	struct delayed_work msg_timer_work;
80 	struct work_struct work;
81 	struct strp_stats stats;
82 	struct strp_callbacks cb;
83 };
84 
85 /* Must be called with lock held for attached socket */
86 static inline void strp_pause(struct strparser *strp)
87 {
88 	strp->paused = 1;
89 }
90 
91 /* May be called without holding lock for attached socket */
92 void strp_unpause(struct strparser *strp);
93 /* Must be called with process lock held (lock_sock) */
94 void __strp_unpause(struct strparser *strp);
95 
96 static inline void save_strp_stats(struct strparser *strp,
97 				   struct strp_aggr_stats *agg_stats)
98 {
99 	/* Save psock statistics in the mux when psock is being unattached. */
100 
101 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat +=		\
102 				 strp->stats._stat)
103 	SAVE_PSOCK_STATS(msgs);
104 	SAVE_PSOCK_STATS(bytes);
105 	SAVE_PSOCK_STATS(mem_fail);
106 	SAVE_PSOCK_STATS(need_more_hdr);
107 	SAVE_PSOCK_STATS(msg_too_big);
108 	SAVE_PSOCK_STATS(msg_timeouts);
109 	SAVE_PSOCK_STATS(bad_hdr_len);
110 #undef SAVE_PSOCK_STATS
111 
112 	if (strp->aborted)
113 		agg_stats->aborts++;
114 	if (strp->interrupted)
115 		agg_stats->interrupted++;
116 	if (strp->unrecov_intr)
117 		agg_stats->unrecov_intr++;
118 }
119 
120 static inline void aggregate_strp_stats(struct strp_aggr_stats *stats,
121 					struct strp_aggr_stats *agg_stats)
122 {
123 #define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
124 	SAVE_PSOCK_STATS(msgs);
125 	SAVE_PSOCK_STATS(bytes);
126 	SAVE_PSOCK_STATS(mem_fail);
127 	SAVE_PSOCK_STATS(need_more_hdr);
128 	SAVE_PSOCK_STATS(msg_too_big);
129 	SAVE_PSOCK_STATS(msg_timeouts);
130 	SAVE_PSOCK_STATS(bad_hdr_len);
131 	SAVE_PSOCK_STATS(aborts);
132 	SAVE_PSOCK_STATS(interrupted);
133 	SAVE_PSOCK_STATS(unrecov_intr);
134 #undef SAVE_PSOCK_STATS
135 
136 }
137 
138 void strp_done(struct strparser *strp);
139 void strp_stop(struct strparser *strp);
140 void strp_check_rcv(struct strparser *strp);
141 int strp_init(struct strparser *strp, struct sock *sk,
142 	      const struct strp_callbacks *cb);
143 void strp_data_ready(struct strparser *strp);
144 int strp_process(struct strparser *strp, struct sk_buff *orig_skb,
145 		 unsigned int orig_offset, size_t orig_len,
146 		 size_t max_msg_size, long timeo);
147 
148 #endif /* __NET_STRPARSER_H_ */
149