xref: /openbmc/linux/include/net/xdp_sock.h (revision 67bf4745)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* AF_XDP internal functions
3  * Copyright(c) 2018 Intel Corporation.
4  */
5 
6 #ifndef _LINUX_XDP_SOCK_H
7 #define _LINUX_XDP_SOCK_H
8 
9 #include <linux/workqueue.h>
10 #include <linux/if_xdp.h>
11 #include <linux/mutex.h>
12 #include <linux/spinlock.h>
13 #include <linux/mm.h>
14 #include <net/sock.h>
15 
16 struct net_device;
17 struct xsk_queue;
18 
19 struct xdp_umem_page {
20 	void *addr;
21 	dma_addr_t dma;
22 };
23 
24 struct xdp_umem_fq_reuse {
25 	u32 nentries;
26 	u32 length;
27 	u64 handles[];
28 };
29 
30 struct xdp_umem {
31 	struct xsk_queue *fq;
32 	struct xsk_queue *cq;
33 	struct xdp_umem_page *pages;
34 	u64 chunk_mask;
35 	u64 size;
36 	u32 headroom;
37 	u32 chunk_size_nohr;
38 	struct user_struct *user;
39 	unsigned long address;
40 	refcount_t users;
41 	struct work_struct work;
42 	struct page **pgs;
43 	u32 npgs;
44 	int id;
45 	struct net_device *dev;
46 	struct xdp_umem_fq_reuse *fq_reuse;
47 	u16 queue_id;
48 	bool zc;
49 	spinlock_t xsk_list_lock;
50 	struct list_head xsk_list;
51 };
52 
53 struct xdp_sock {
54 	/* struct sock must be the first member of struct xdp_sock */
55 	struct sock sk;
56 	struct xsk_queue *rx;
57 	struct net_device *dev;
58 	struct xdp_umem *umem;
59 	struct list_head flush_node;
60 	u16 queue_id;
61 	bool zc;
62 	enum {
63 		XSK_READY = 0,
64 		XSK_BOUND,
65 		XSK_UNBOUND,
66 	} state;
67 	/* Protects multiple processes in the control path */
68 	struct mutex mutex;
69 	struct xsk_queue *tx ____cacheline_aligned_in_smp;
70 	struct list_head list;
71 	/* Mutual exclusion of NAPI TX thread and sendmsg error paths
72 	 * in the SKB destructor callback.
73 	 */
74 	spinlock_t tx_completion_lock;
75 	/* Protects generic receive. */
76 	spinlock_t rx_lock;
77 	u64 rx_dropped;
78 };
79 
80 struct xdp_buff;
81 #ifdef CONFIG_XDP_SOCKETS
82 int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
83 int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
84 void xsk_flush(struct xdp_sock *xs);
85 bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs);
86 /* Used from netdev driver */
87 bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt);
88 u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr);
89 void xsk_umem_discard_addr(struct xdp_umem *umem);
90 void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries);
91 bool xsk_umem_consume_tx(struct xdp_umem *umem, struct xdp_desc *desc);
92 void xsk_umem_consume_tx_done(struct xdp_umem *umem);
93 struct xdp_umem_fq_reuse *xsk_reuseq_prepare(u32 nentries);
94 struct xdp_umem_fq_reuse *xsk_reuseq_swap(struct xdp_umem *umem,
95 					  struct xdp_umem_fq_reuse *newq);
96 void xsk_reuseq_free(struct xdp_umem_fq_reuse *rq);
97 struct xdp_umem *xdp_get_umem_from_qid(struct net_device *dev, u16 queue_id);
98 
99 static inline char *xdp_umem_get_data(struct xdp_umem *umem, u64 addr)
100 {
101 	return umem->pages[addr >> PAGE_SHIFT].addr + (addr & (PAGE_SIZE - 1));
102 }
103 
104 static inline dma_addr_t xdp_umem_get_dma(struct xdp_umem *umem, u64 addr)
105 {
106 	return umem->pages[addr >> PAGE_SHIFT].dma + (addr & (PAGE_SIZE - 1));
107 }
108 
109 /* Reuse-queue aware version of FILL queue helpers */
110 static inline bool xsk_umem_has_addrs_rq(struct xdp_umem *umem, u32 cnt)
111 {
112 	struct xdp_umem_fq_reuse *rq = umem->fq_reuse;
113 
114 	if (rq->length >= cnt)
115 		return true;
116 
117 	return xsk_umem_has_addrs(umem, cnt - rq->length);
118 }
119 
120 static inline u64 *xsk_umem_peek_addr_rq(struct xdp_umem *umem, u64 *addr)
121 {
122 	struct xdp_umem_fq_reuse *rq = umem->fq_reuse;
123 
124 	if (!rq->length)
125 		return xsk_umem_peek_addr(umem, addr);
126 
127 	*addr = rq->handles[rq->length - 1];
128 	return addr;
129 }
130 
131 static inline void xsk_umem_discard_addr_rq(struct xdp_umem *umem)
132 {
133 	struct xdp_umem_fq_reuse *rq = umem->fq_reuse;
134 
135 	if (!rq->length)
136 		xsk_umem_discard_addr(umem);
137 	else
138 		rq->length--;
139 }
140 
141 static inline void xsk_umem_fq_reuse(struct xdp_umem *umem, u64 addr)
142 {
143 	struct xdp_umem_fq_reuse *rq = umem->fq_reuse;
144 
145 	rq->handles[rq->length++] = addr;
146 }
147 #else
148 static inline int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
149 {
150 	return -ENOTSUPP;
151 }
152 
153 static inline int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
154 {
155 	return -ENOTSUPP;
156 }
157 
158 static inline void xsk_flush(struct xdp_sock *xs)
159 {
160 }
161 
162 static inline bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs)
163 {
164 	return false;
165 }
166 
167 static inline bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt)
168 {
169 	return false;
170 }
171 
172 static inline u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr)
173 {
174 	return NULL;
175 }
176 
177 static inline void xsk_umem_discard_addr(struct xdp_umem *umem)
178 {
179 }
180 
181 static inline void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries)
182 {
183 }
184 
185 static inline bool xsk_umem_consume_tx(struct xdp_umem *umem,
186 				       struct xdp_desc *desc)
187 {
188 	return false;
189 }
190 
191 static inline void xsk_umem_consume_tx_done(struct xdp_umem *umem)
192 {
193 }
194 
195 static inline struct xdp_umem_fq_reuse *xsk_reuseq_prepare(u32 nentries)
196 {
197 	return NULL;
198 }
199 
200 static inline struct xdp_umem_fq_reuse *xsk_reuseq_swap(
201 	struct xdp_umem *umem,
202 	struct xdp_umem_fq_reuse *newq)
203 {
204 	return NULL;
205 }
206 static inline void xsk_reuseq_free(struct xdp_umem_fq_reuse *rq)
207 {
208 }
209 
210 static inline struct xdp_umem *xdp_get_umem_from_qid(struct net_device *dev,
211 						     u16 queue_id)
212 {
213 	return NULL;
214 }
215 
216 static inline char *xdp_umem_get_data(struct xdp_umem *umem, u64 addr)
217 {
218 	return NULL;
219 }
220 
221 static inline dma_addr_t xdp_umem_get_dma(struct xdp_umem *umem, u64 addr)
222 {
223 	return 0;
224 }
225 
226 static inline bool xsk_umem_has_addrs_rq(struct xdp_umem *umem, u32 cnt)
227 {
228 	return false;
229 }
230 
231 static inline u64 *xsk_umem_peek_addr_rq(struct xdp_umem *umem, u64 *addr)
232 {
233 	return NULL;
234 }
235 
236 static inline void xsk_umem_discard_addr_rq(struct xdp_umem *umem)
237 {
238 }
239 
240 static inline void xsk_umem_fq_reuse(struct xdp_umem *umem, u64 addr)
241 {
242 }
243 
244 #endif /* CONFIG_XDP_SOCKETS */
245 
246 #endif /* _LINUX_XDP_SOCK_H */
247