xref: /openbmc/linux/include/linux/skb_array.h (revision 0a73d21e)
1 /*
2  *	Definitions for the 'struct skb_array' datastructure.
3  *
4  *	Author:
5  *		Michael S. Tsirkin <mst@redhat.com>
6  *
7  *	Copyright (C) 2016 Red Hat, Inc.
8  *
9  *	This program is free software; you can redistribute it and/or modify it
10  *	under the terms of the GNU General Public License as published by the
11  *	Free Software Foundation; either version 2 of the License, or (at your
12  *	option) any later version.
13  *
14  *	Limited-size FIFO of skbs. Can be used more or less whenever
15  *	sk_buff_head can be used, except you need to know the queue size in
16  *	advance.
17  *	Implemented as a type-safe wrapper around ptr_ring.
18  */
19 
20 #ifndef _LINUX_SKB_ARRAY_H
21 #define _LINUX_SKB_ARRAY_H 1
22 
23 #ifdef __KERNEL__
24 #include <linux/ptr_ring.h>
25 #include <linux/skbuff.h>
26 #include <linux/if_vlan.h>
27 #endif
28 
29 struct skb_array {
30 	struct ptr_ring ring;
31 };
32 
33 /* Might be slightly faster than skb_array_full below, but callers invoking
34  * this in a loop must use a compiler barrier, for example cpu_relax().
35  */
36 static inline bool __skb_array_full(struct skb_array *a)
37 {
38 	return __ptr_ring_full(&a->ring);
39 }
40 
41 static inline bool skb_array_full(struct skb_array *a)
42 {
43 	return ptr_ring_full(&a->ring);
44 }
45 
46 static inline int skb_array_produce(struct skb_array *a, struct sk_buff *skb)
47 {
48 	return ptr_ring_produce(&a->ring, skb);
49 }
50 
51 static inline int skb_array_produce_irq(struct skb_array *a, struct sk_buff *skb)
52 {
53 	return ptr_ring_produce_irq(&a->ring, skb);
54 }
55 
56 static inline int skb_array_produce_bh(struct skb_array *a, struct sk_buff *skb)
57 {
58 	return ptr_ring_produce_bh(&a->ring, skb);
59 }
60 
61 static inline int skb_array_produce_any(struct skb_array *a, struct sk_buff *skb)
62 {
63 	return ptr_ring_produce_any(&a->ring, skb);
64 }
65 
66 /* Might be slightly faster than skb_array_empty below, but only safe if the
67  * array is never resized. Also, callers invoking this in a loop must take care
68  * to use a compiler barrier, for example cpu_relax().
69  */
70 static inline bool __skb_array_empty(struct skb_array *a)
71 {
72 	return __ptr_ring_empty(&a->ring);
73 }
74 
75 static inline struct sk_buff *__skb_array_peek(struct skb_array *a)
76 {
77 	return __ptr_ring_peek(&a->ring);
78 }
79 
80 static inline bool skb_array_empty(struct skb_array *a)
81 {
82 	return ptr_ring_empty(&a->ring);
83 }
84 
85 static inline bool skb_array_empty_bh(struct skb_array *a)
86 {
87 	return ptr_ring_empty_bh(&a->ring);
88 }
89 
90 static inline bool skb_array_empty_irq(struct skb_array *a)
91 {
92 	return ptr_ring_empty_irq(&a->ring);
93 }
94 
95 static inline bool skb_array_empty_any(struct skb_array *a)
96 {
97 	return ptr_ring_empty_any(&a->ring);
98 }
99 
100 static inline struct sk_buff *skb_array_consume(struct skb_array *a)
101 {
102 	return ptr_ring_consume(&a->ring);
103 }
104 
105 static inline int skb_array_consume_batched(struct skb_array *a,
106 					    struct sk_buff **array, int n)
107 {
108 	return ptr_ring_consume_batched(&a->ring, (void **)array, n);
109 }
110 
111 static inline struct sk_buff *skb_array_consume_irq(struct skb_array *a)
112 {
113 	return ptr_ring_consume_irq(&a->ring);
114 }
115 
116 static inline int skb_array_consume_batched_irq(struct skb_array *a,
117 						struct sk_buff **array, int n)
118 {
119 	return ptr_ring_consume_batched_irq(&a->ring, (void **)array, n);
120 }
121 
122 static inline struct sk_buff *skb_array_consume_any(struct skb_array *a)
123 {
124 	return ptr_ring_consume_any(&a->ring);
125 }
126 
127 static inline int skb_array_consume_batched_any(struct skb_array *a,
128 						struct sk_buff **array, int n)
129 {
130 	return ptr_ring_consume_batched_any(&a->ring, (void **)array, n);
131 }
132 
133 
134 static inline struct sk_buff *skb_array_consume_bh(struct skb_array *a)
135 {
136 	return ptr_ring_consume_bh(&a->ring);
137 }
138 
139 static inline int skb_array_consume_batched_bh(struct skb_array *a,
140 					       struct sk_buff **array, int n)
141 {
142 	return ptr_ring_consume_batched_bh(&a->ring, (void **)array, n);
143 }
144 
145 static inline int __skb_array_len_with_tag(struct sk_buff *skb)
146 {
147 	if (likely(skb)) {
148 		int len = skb->len;
149 
150 		if (skb_vlan_tag_present(skb))
151 			len += VLAN_HLEN;
152 
153 		return len;
154 	} else {
155 		return 0;
156 	}
157 }
158 
159 static inline int skb_array_peek_len(struct skb_array *a)
160 {
161 	return PTR_RING_PEEK_CALL(&a->ring, __skb_array_len_with_tag);
162 }
163 
164 static inline int skb_array_peek_len_irq(struct skb_array *a)
165 {
166 	return PTR_RING_PEEK_CALL_IRQ(&a->ring, __skb_array_len_with_tag);
167 }
168 
169 static inline int skb_array_peek_len_bh(struct skb_array *a)
170 {
171 	return PTR_RING_PEEK_CALL_BH(&a->ring, __skb_array_len_with_tag);
172 }
173 
174 static inline int skb_array_peek_len_any(struct skb_array *a)
175 {
176 	return PTR_RING_PEEK_CALL_ANY(&a->ring, __skb_array_len_with_tag);
177 }
178 
179 static inline int skb_array_init(struct skb_array *a, int size, gfp_t gfp)
180 {
181 	return ptr_ring_init(&a->ring, size, gfp);
182 }
183 
184 static void __skb_array_destroy_skb(void *ptr)
185 {
186 	kfree_skb(ptr);
187 }
188 
189 static inline void skb_array_unconsume(struct skb_array *a,
190 				       struct sk_buff **skbs, int n)
191 {
192 	ptr_ring_unconsume(&a->ring, (void **)skbs, n, __skb_array_destroy_skb);
193 }
194 
195 static inline int skb_array_resize(struct skb_array *a, int size, gfp_t gfp)
196 {
197 	return ptr_ring_resize(&a->ring, size, gfp, __skb_array_destroy_skb);
198 }
199 
200 static inline int skb_array_resize_multiple(struct skb_array **rings,
201 					    int nrings, unsigned int size,
202 					    gfp_t gfp)
203 {
204 	BUILD_BUG_ON(offsetof(struct skb_array, ring));
205 	return ptr_ring_resize_multiple((struct ptr_ring **)rings,
206 					nrings, size, gfp,
207 					__skb_array_destroy_skb);
208 }
209 
210 static inline void skb_array_cleanup(struct skb_array *a)
211 {
212 	ptr_ring_cleanup(&a->ring, __skb_array_destroy_skb);
213 }
214 
215 #endif /* _LINUX_SKB_ARRAY_H  */
216