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11#ifndef __LIBBPF_XSK_H
12#define __LIBBPF_XSK_H
13
14#include <stdio.h>
15#include <stdint.h>
16#include <linux/if_xdp.h>
17
18#include "libbpf.h"
19#include "libbpf_util.h"
20
21#ifdef __cplusplus
22extern "C" {
23#endif
24
25
26#define DEFINE_XSK_RING(name) \
27struct name { \
28 __u32 cached_prod; \
29 __u32 cached_cons; \
30 __u32 mask; \
31 __u32 size; \
32 __u32 *producer; \
33 __u32 *consumer; \
34 void *ring; \
35 __u32 *flags; \
36}
37
38DEFINE_XSK_RING(xsk_ring_prod);
39DEFINE_XSK_RING(xsk_ring_cons);
40
41
42
43
44
45struct xsk_umem;
46struct xsk_socket;
47
48static inline __u64 *xsk_ring_prod__fill_addr(struct xsk_ring_prod *fill,
49 __u32 idx)
50{
51 __u64 *addrs = (__u64 *)fill->ring;
52
53 return &addrs[idx & fill->mask];
54}
55
56static inline const __u64 *
57xsk_ring_cons__comp_addr(const struct xsk_ring_cons *comp, __u32 idx)
58{
59 const __u64 *addrs = (const __u64 *)comp->ring;
60
61 return &addrs[idx & comp->mask];
62}
63
64static inline struct xdp_desc *xsk_ring_prod__tx_desc(struct xsk_ring_prod *tx,
65 __u32 idx)
66{
67 struct xdp_desc *descs = (struct xdp_desc *)tx->ring;
68
69 return &descs[idx & tx->mask];
70}
71
72static inline const struct xdp_desc *
73xsk_ring_cons__rx_desc(const struct xsk_ring_cons *rx, __u32 idx)
74{
75 const struct xdp_desc *descs = (const struct xdp_desc *)rx->ring;
76
77 return &descs[idx & rx->mask];
78}
79
80static inline int xsk_ring_prod__needs_wakeup(const struct xsk_ring_prod *r)
81{
82 return *r->flags & XDP_RING_NEED_WAKEUP;
83}
84
85static inline __u32 xsk_prod_nb_free(struct xsk_ring_prod *r, __u32 nb)
86{
87 __u32 free_entries = r->cached_cons - r->cached_prod;
88
89 if (free_entries >= nb)
90 return free_entries;
91
92
93
94
95
96
97
98
99 r->cached_cons = *r->consumer + r->size;
100
101 return r->cached_cons - r->cached_prod;
102}
103
104static inline __u32 xsk_cons_nb_avail(struct xsk_ring_cons *r, __u32 nb)
105{
106 __u32 entries = r->cached_prod - r->cached_cons;
107
108 if (entries == 0) {
109 r->cached_prod = *r->producer;
110 entries = r->cached_prod - r->cached_cons;
111 }
112
113 return (entries > nb) ? nb : entries;
114}
115
116static inline __u32 xsk_ring_prod__reserve(struct xsk_ring_prod *prod, __u32 nb, __u32 *idx)
117{
118 if (xsk_prod_nb_free(prod, nb) < nb)
119 return 0;
120
121 *idx = prod->cached_prod;
122 prod->cached_prod += nb;
123
124 return nb;
125}
126
127static inline void xsk_ring_prod__submit(struct xsk_ring_prod *prod, __u32 nb)
128{
129
130
131
132 libbpf_smp_wmb();
133
134 *prod->producer += nb;
135}
136
137static inline __u32 xsk_ring_cons__peek(struct xsk_ring_cons *cons, __u32 nb, __u32 *idx)
138{
139 __u32 entries = xsk_cons_nb_avail(cons, nb);
140
141 if (entries > 0) {
142
143
144
145 libbpf_smp_rmb();
146
147 *idx = cons->cached_cons;
148 cons->cached_cons += entries;
149 }
150
151 return entries;
152}
153
154static inline void xsk_ring_cons__cancel(struct xsk_ring_cons *cons, __u32 nb)
155{
156 cons->cached_cons -= nb;
157}
158
159static inline void xsk_ring_cons__release(struct xsk_ring_cons *cons, __u32 nb)
160{
161
162
163
164 libbpf_smp_rwmb();
165
166 *cons->consumer += nb;
167}
168
169static inline void *xsk_umem__get_data(void *umem_area, __u64 addr)
170{
171 return &((char *)umem_area)[addr];
172}
173
174static inline __u64 xsk_umem__extract_addr(__u64 addr)
175{
176 return addr & XSK_UNALIGNED_BUF_ADDR_MASK;
177}
178
179static inline __u64 xsk_umem__extract_offset(__u64 addr)
180{
181 return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT;
182}
183
184static inline __u64 xsk_umem__add_offset_to_addr(__u64 addr)
185{
186 return xsk_umem__extract_addr(addr) + xsk_umem__extract_offset(addr);
187}
188
189LIBBPF_API int xsk_umem__fd(const struct xsk_umem *umem);
190LIBBPF_API int xsk_socket__fd(const struct xsk_socket *xsk);
191
192#define XSK_RING_CONS__DEFAULT_NUM_DESCS 2048
193#define XSK_RING_PROD__DEFAULT_NUM_DESCS 2048
194#define XSK_UMEM__DEFAULT_FRAME_SHIFT 12
195#define XSK_UMEM__DEFAULT_FRAME_SIZE (1 << XSK_UMEM__DEFAULT_FRAME_SHIFT)
196#define XSK_UMEM__DEFAULT_FRAME_HEADROOM 0
197#define XSK_UMEM__DEFAULT_FLAGS 0
198
199struct xsk_umem_config {
200 __u32 fill_size;
201 __u32 comp_size;
202 __u32 frame_size;
203 __u32 frame_headroom;
204 __u32 flags;
205};
206
207LIBBPF_API int xsk_setup_xdp_prog(int ifindex,
208 int *xsks_map_fd);
209LIBBPF_API int xsk_socket__update_xskmap(struct xsk_socket *xsk,
210 int xsks_map_fd);
211
212
213#define XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD (1 << 0)
214
215struct xsk_socket_config {
216 __u32 rx_size;
217 __u32 tx_size;
218 __u32 libbpf_flags;
219 __u32 xdp_flags;
220 __u16 bind_flags;
221};
222
223
224LIBBPF_API int xsk_umem__create(struct xsk_umem **umem,
225 void *umem_area, __u64 size,
226 struct xsk_ring_prod *fill,
227 struct xsk_ring_cons *comp,
228 const struct xsk_umem_config *config);
229LIBBPF_API int xsk_umem__create_v0_0_2(struct xsk_umem **umem,
230 void *umem_area, __u64 size,
231 struct xsk_ring_prod *fill,
232 struct xsk_ring_cons *comp,
233 const struct xsk_umem_config *config);
234LIBBPF_API int xsk_umem__create_v0_0_4(struct xsk_umem **umem,
235 void *umem_area, __u64 size,
236 struct xsk_ring_prod *fill,
237 struct xsk_ring_cons *comp,
238 const struct xsk_umem_config *config);
239LIBBPF_API int xsk_socket__create(struct xsk_socket **xsk,
240 const char *ifname, __u32 queue_id,
241 struct xsk_umem *umem,
242 struct xsk_ring_cons *rx,
243 struct xsk_ring_prod *tx,
244 const struct xsk_socket_config *config);
245LIBBPF_API int
246xsk_socket__create_shared(struct xsk_socket **xsk_ptr,
247 const char *ifname,
248 __u32 queue_id, struct xsk_umem *umem,
249 struct xsk_ring_cons *rx,
250 struct xsk_ring_prod *tx,
251 struct xsk_ring_prod *fill,
252 struct xsk_ring_cons *comp,
253 const struct xsk_socket_config *config);
254
255
256LIBBPF_API int xsk_umem__delete(struct xsk_umem *umem);
257LIBBPF_API void xsk_socket__delete(struct xsk_socket *xsk);
258
259#ifdef __cplusplus
260}
261#endif
262
263#endif
264