xref: /openbmc/linux/include/net/xdp_sock.h (revision ebd09753)
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 	struct pid *pid;
40 	unsigned long address;
41 	refcount_t users;
42 	struct work_struct work;
43 	struct page **pgs;
44 	u32 npgs;
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 	struct xsk_queue *tx ____cacheline_aligned_in_smp;
62 	struct list_head list;
63 	bool zc;
64 	/* Protects multiple processes in the control path */
65 	struct mutex mutex;
66 	/* Mutual exclusion of NAPI TX thread and sendmsg error paths
67 	 * in the SKB destructor callback.
68 	 */
69 	spinlock_t tx_completion_lock;
70 	u64 rx_dropped;
71 };
72 
73 struct xdp_buff;
74 #ifdef CONFIG_XDP_SOCKETS
75 int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
76 int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
77 void xsk_flush(struct xdp_sock *xs);
78 bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs);
79 /* Used from netdev driver */
80 u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr);
81 void xsk_umem_discard_addr(struct xdp_umem *umem);
82 void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries);
83 bool xsk_umem_consume_tx(struct xdp_umem *umem, dma_addr_t *dma, u32 *len);
84 void xsk_umem_consume_tx_done(struct xdp_umem *umem);
85 struct xdp_umem_fq_reuse *xsk_reuseq_prepare(u32 nentries);
86 struct xdp_umem_fq_reuse *xsk_reuseq_swap(struct xdp_umem *umem,
87 					  struct xdp_umem_fq_reuse *newq);
88 void xsk_reuseq_free(struct xdp_umem_fq_reuse *rq);
89 struct xdp_umem *xdp_get_umem_from_qid(struct net_device *dev, u16 queue_id);
90 
91 static inline char *xdp_umem_get_data(struct xdp_umem *umem, u64 addr)
92 {
93 	return umem->pages[addr >> PAGE_SHIFT].addr + (addr & (PAGE_SIZE - 1));
94 }
95 
96 static inline dma_addr_t xdp_umem_get_dma(struct xdp_umem *umem, u64 addr)
97 {
98 	return umem->pages[addr >> PAGE_SHIFT].dma + (addr & (PAGE_SIZE - 1));
99 }
100 
101 /* Reuse-queue aware version of FILL queue helpers */
102 static inline u64 *xsk_umem_peek_addr_rq(struct xdp_umem *umem, u64 *addr)
103 {
104 	struct xdp_umem_fq_reuse *rq = umem->fq_reuse;
105 
106 	if (!rq->length)
107 		return xsk_umem_peek_addr(umem, addr);
108 
109 	*addr = rq->handles[rq->length - 1];
110 	return addr;
111 }
112 
113 static inline void xsk_umem_discard_addr_rq(struct xdp_umem *umem)
114 {
115 	struct xdp_umem_fq_reuse *rq = umem->fq_reuse;
116 
117 	if (!rq->length)
118 		xsk_umem_discard_addr(umem);
119 	else
120 		rq->length--;
121 }
122 
123 static inline void xsk_umem_fq_reuse(struct xdp_umem *umem, u64 addr)
124 {
125 	struct xdp_umem_fq_reuse *rq = umem->fq_reuse;
126 
127 	rq->handles[rq->length++] = addr;
128 }
129 #else
130 static inline int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
131 {
132 	return -ENOTSUPP;
133 }
134 
135 static inline int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
136 {
137 	return -ENOTSUPP;
138 }
139 
140 static inline void xsk_flush(struct xdp_sock *xs)
141 {
142 }
143 
144 static inline bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs)
145 {
146 	return false;
147 }
148 
149 static inline u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr)
150 {
151 	return NULL;
152 }
153 
154 static inline void xsk_umem_discard_addr(struct xdp_umem *umem)
155 {
156 }
157 
158 static inline void xsk_umem_complete_tx(struct xdp_umem *umem, u32 nb_entries)
159 {
160 }
161 
162 static inline bool xsk_umem_consume_tx(struct xdp_umem *umem, dma_addr_t *dma,
163 				       u32 *len)
164 {
165 	return false;
166 }
167 
168 static inline void xsk_umem_consume_tx_done(struct xdp_umem *umem)
169 {
170 }
171 
172 static inline struct xdp_umem_fq_reuse *xsk_reuseq_prepare(u32 nentries)
173 {
174 	return NULL;
175 }
176 
177 static inline struct xdp_umem_fq_reuse *xsk_reuseq_swap(
178 	struct xdp_umem *umem,
179 	struct xdp_umem_fq_reuse *newq)
180 {
181 	return NULL;
182 }
183 static inline void xsk_reuseq_free(struct xdp_umem_fq_reuse *rq)
184 {
185 }
186 
187 static inline struct xdp_umem *xdp_get_umem_from_qid(struct net_device *dev,
188 						     u16 queue_id)
189 {
190 	return NULL;
191 }
192 
193 static inline char *xdp_umem_get_data(struct xdp_umem *umem, u64 addr)
194 {
195 	return NULL;
196 }
197 
198 static inline dma_addr_t xdp_umem_get_dma(struct xdp_umem *umem, u64 addr)
199 {
200 	return 0;
201 }
202 
203 static inline u64 *xsk_umem_peek_addr_rq(struct xdp_umem *umem, u64 *addr)
204 {
205 	return NULL;
206 }
207 
208 static inline void xsk_umem_discard_addr_rq(struct xdp_umem *umem)
209 {
210 }
211 
212 static inline void xsk_umem_fq_reuse(struct xdp_umem *umem, u64 addr)
213 {
214 }
215 
216 #endif /* CONFIG_XDP_SOCKETS */
217 
218 #endif /* _LINUX_XDP_SOCK_H */
219