xref: /linux/include/net/xdp_sock_drv.h (revision 79ac11393328fb1717d17c12e3c0eef0e9fa0647) 
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Interface for implementing AF_XDP zero-copy support in drivers.
3  * Copyright(c) 2020 Intel Corporation.
4  */
5 
6 #ifndef _LINUX_XDP_SOCK_DRV_H
7 #define _LINUX_XDP_SOCK_DRV_H
8 
9 #include <net/xdp_sock.h>
10 #include <net/xsk_buff_pool.h>
11 
12 #define XDP_UMEM_MIN_CHUNK_SHIFT 11
13 #define XDP_UMEM_MIN_CHUNK_SIZE (1 << XDP_UMEM_MIN_CHUNK_SHIFT)
14 
15 #ifdef CONFIG_XDP_SOCKETS
16 
17 void xsk_tx_completed(struct xsk_buff_pool *pool, u32 nb_entries);
18 bool xsk_tx_peek_desc(struct xsk_buff_pool *pool, struct xdp_desc *desc);
19 u32 xsk_tx_peek_release_desc_batch(struct xsk_buff_pool *pool, u32 max);
20 void xsk_tx_release(struct xsk_buff_pool *pool);
21 struct xsk_buff_pool *xsk_get_pool_from_qid(struct net_device *dev,
22 					    u16 queue_id);
23 void xsk_set_rx_need_wakeup(struct xsk_buff_pool *pool);
24 void xsk_set_tx_need_wakeup(struct xsk_buff_pool *pool);
25 void xsk_clear_rx_need_wakeup(struct xsk_buff_pool *pool);
26 void xsk_clear_tx_need_wakeup(struct xsk_buff_pool *pool);
27 bool xsk_uses_need_wakeup(struct xsk_buff_pool *pool);
28 
29 static inline u32 xsk_pool_get_headroom(struct xsk_buff_pool *pool)
30 {
31 	return XDP_PACKET_HEADROOM + pool->headroom;
32 }
33 
34 static inline u32 xsk_pool_get_chunk_size(struct xsk_buff_pool *pool)
35 {
36 	return pool->chunk_size;
37 }
38 
39 static inline u32 xsk_pool_get_rx_frame_size(struct xsk_buff_pool *pool)
40 {
41 	return xsk_pool_get_chunk_size(pool) - xsk_pool_get_headroom(pool);
42 }
43 
44 static inline void xsk_pool_set_rxq_info(struct xsk_buff_pool *pool,
45 					 struct xdp_rxq_info *rxq)
46 {
47 	xp_set_rxq_info(pool, rxq);
48 }
49 
50 static inline unsigned int xsk_pool_get_napi_id(struct xsk_buff_pool *pool)
51 {
52 #ifdef CONFIG_NET_RX_BUSY_POLL
53 	return pool->heads[0].xdp.rxq->napi_id;
54 #else
55 	return 0;
56 #endif
57 }
58 
59 static inline void xsk_pool_dma_unmap(struct xsk_buff_pool *pool,
60 				      unsigned long attrs)
61 {
62 	xp_dma_unmap(pool, attrs);
63 }
64 
65 static inline int xsk_pool_dma_map(struct xsk_buff_pool *pool,
66 				   struct device *dev, unsigned long attrs)
67 {
68 	struct xdp_umem *umem = pool->umem;
69 
70 	return xp_dma_map(pool, dev, attrs, umem->pgs, umem->npgs);
71 }
72 
73 static inline dma_addr_t xsk_buff_xdp_get_dma(struct xdp_buff *xdp)
74 {
75 	struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
76 
77 	return xp_get_dma(xskb);
78 }
79 
80 static inline dma_addr_t xsk_buff_xdp_get_frame_dma(struct xdp_buff *xdp)
81 {
82 	struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
83 
84 	return xp_get_frame_dma(xskb);
85 }
86 
87 static inline struct xdp_buff *xsk_buff_alloc(struct xsk_buff_pool *pool)
88 {
89 	return xp_alloc(pool);
90 }
91 
92 static inline bool xsk_is_eop_desc(struct xdp_desc *desc)
93 {
94 	return !xp_mb_desc(desc);
95 }
96 
97 /* Returns as many entries as possible up to max. 0 <= N <= max. */
98 static inline u32 xsk_buff_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
99 {
100 	return xp_alloc_batch(pool, xdp, max);
101 }
102 
103 static inline bool xsk_buff_can_alloc(struct xsk_buff_pool *pool, u32 count)
104 {
105 	return xp_can_alloc(pool, count);
106 }
107 
108 static inline void xsk_buff_free(struct xdp_buff *xdp)
109 {
110 	struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
111 	struct list_head *xskb_list = &xskb->pool->xskb_list;
112 	struct xdp_buff_xsk *pos, *tmp;
113 
114 	if (likely(!xdp_buff_has_frags(xdp)))
115 		goto out;
116 
117 	list_for_each_entry_safe(pos, tmp, xskb_list, xskb_list_node) {
118 		list_del(&pos->xskb_list_node);
119 		xp_free(pos);
120 	}
121 
122 	xdp_get_shared_info_from_buff(xdp)->nr_frags = 0;
123 out:
124 	xp_free(xskb);
125 }
126 
127 static inline void xsk_buff_add_frag(struct xdp_buff *xdp)
128 {
129 	struct xdp_buff_xsk *frag = container_of(xdp, struct xdp_buff_xsk, xdp);
130 
131 	list_add_tail(&frag->xskb_list_node, &frag->pool->xskb_list);
132 }
133 
134 static inline struct xdp_buff *xsk_buff_get_frag(struct xdp_buff *first)
135 {
136 	struct xdp_buff_xsk *xskb = container_of(first, struct xdp_buff_xsk, xdp);
137 	struct xdp_buff *ret = NULL;
138 	struct xdp_buff_xsk *frag;
139 
140 	frag = list_first_entry_or_null(&xskb->pool->xskb_list,
141 					struct xdp_buff_xsk, xskb_list_node);
142 	if (frag) {
143 		list_del(&frag->xskb_list_node);
144 		ret = &frag->xdp;
145 	}
146 
147 	return ret;
148 }
149 
150 static inline void xsk_buff_set_size(struct xdp_buff *xdp, u32 size)
151 {
152 	xdp->data = xdp->data_hard_start + XDP_PACKET_HEADROOM;
153 	xdp->data_meta = xdp->data;
154 	xdp->data_end = xdp->data + size;
155 }
156 
157 static inline dma_addr_t xsk_buff_raw_get_dma(struct xsk_buff_pool *pool,
158 					      u64 addr)
159 {
160 	return xp_raw_get_dma(pool, addr);
161 }
162 
163 static inline void *xsk_buff_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
164 {
165 	return xp_raw_get_data(pool, addr);
166 }
167 
168 #define XDP_TXMD_FLAGS_VALID ( \
169 		XDP_TXMD_FLAGS_TIMESTAMP | \
170 		XDP_TXMD_FLAGS_CHECKSUM | \
171 	0)
172 
173 static inline bool xsk_buff_valid_tx_metadata(struct xsk_tx_metadata *meta)
174 {
175 	return !(meta->flags & ~XDP_TXMD_FLAGS_VALID);
176 }
177 
178 static inline struct xsk_tx_metadata *xsk_buff_get_metadata(struct xsk_buff_pool *pool, u64 addr)
179 {
180 	struct xsk_tx_metadata *meta;
181 
182 	if (!pool->tx_metadata_len)
183 		return NULL;
184 
185 	meta = xp_raw_get_data(pool, addr) - pool->tx_metadata_len;
186 	if (unlikely(!xsk_buff_valid_tx_metadata(meta)))
187 		return NULL; /* no way to signal the error to the user */
188 
189 	return meta;
190 }
191 
192 static inline void xsk_buff_dma_sync_for_cpu(struct xdp_buff *xdp, struct xsk_buff_pool *pool)
193 {
194 	struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
195 
196 	if (!pool->dma_need_sync)
197 		return;
198 
199 	xp_dma_sync_for_cpu(xskb);
200 }
201 
202 static inline void xsk_buff_raw_dma_sync_for_device(struct xsk_buff_pool *pool,
203 						    dma_addr_t dma,
204 						    size_t size)
205 {
206 	xp_dma_sync_for_device(pool, dma, size);
207 }
208 
209 #else
210 
211 static inline void xsk_tx_completed(struct xsk_buff_pool *pool, u32 nb_entries)
212 {
213 }
214 
215 static inline bool xsk_tx_peek_desc(struct xsk_buff_pool *pool,
216 				    struct xdp_desc *desc)
217 {
218 	return false;
219 }
220 
221 static inline u32 xsk_tx_peek_release_desc_batch(struct xsk_buff_pool *pool, u32 max)
222 {
223 	return 0;
224 }
225 
226 static inline void xsk_tx_release(struct xsk_buff_pool *pool)
227 {
228 }
229 
230 static inline struct xsk_buff_pool *
231 xsk_get_pool_from_qid(struct net_device *dev, u16 queue_id)
232 {
233 	return NULL;
234 }
235 
236 static inline void xsk_set_rx_need_wakeup(struct xsk_buff_pool *pool)
237 {
238 }
239 
240 static inline void xsk_set_tx_need_wakeup(struct xsk_buff_pool *pool)
241 {
242 }
243 
244 static inline void xsk_clear_rx_need_wakeup(struct xsk_buff_pool *pool)
245 {
246 }
247 
248 static inline void xsk_clear_tx_need_wakeup(struct xsk_buff_pool *pool)
249 {
250 }
251 
252 static inline bool xsk_uses_need_wakeup(struct xsk_buff_pool *pool)
253 {
254 	return false;
255 }
256 
257 static inline u32 xsk_pool_get_headroom(struct xsk_buff_pool *pool)
258 {
259 	return 0;
260 }
261 
262 static inline u32 xsk_pool_get_chunk_size(struct xsk_buff_pool *pool)
263 {
264 	return 0;
265 }
266 
267 static inline u32 xsk_pool_get_rx_frame_size(struct xsk_buff_pool *pool)
268 {
269 	return 0;
270 }
271 
272 static inline void xsk_pool_set_rxq_info(struct xsk_buff_pool *pool,
273 					 struct xdp_rxq_info *rxq)
274 {
275 }
276 
277 static inline unsigned int xsk_pool_get_napi_id(struct xsk_buff_pool *pool)
278 {
279 	return 0;
280 }
281 
282 static inline void xsk_pool_dma_unmap(struct xsk_buff_pool *pool,
283 				      unsigned long attrs)
284 {
285 }
286 
287 static inline int xsk_pool_dma_map(struct xsk_buff_pool *pool,
288 				   struct device *dev, unsigned long attrs)
289 {
290 	return 0;
291 }
292 
293 static inline dma_addr_t xsk_buff_xdp_get_dma(struct xdp_buff *xdp)
294 {
295 	return 0;
296 }
297 
298 static inline dma_addr_t xsk_buff_xdp_get_frame_dma(struct xdp_buff *xdp)
299 {
300 	return 0;
301 }
302 
303 static inline struct xdp_buff *xsk_buff_alloc(struct xsk_buff_pool *pool)
304 {
305 	return NULL;
306 }
307 
308 static inline bool xsk_is_eop_desc(struct xdp_desc *desc)
309 {
310 	return false;
311 }
312 
313 static inline u32 xsk_buff_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
314 {
315 	return 0;
316 }
317 
318 static inline bool xsk_buff_can_alloc(struct xsk_buff_pool *pool, u32 count)
319 {
320 	return false;
321 }
322 
323 static inline void xsk_buff_free(struct xdp_buff *xdp)
324 {
325 }
326 
327 static inline void xsk_buff_add_frag(struct xdp_buff *xdp)
328 {
329 }
330 
331 static inline struct xdp_buff *xsk_buff_get_frag(struct xdp_buff *first)
332 {
333 	return NULL;
334 }
335 
336 static inline void xsk_buff_set_size(struct xdp_buff *xdp, u32 size)
337 {
338 }
339 
340 static inline dma_addr_t xsk_buff_raw_get_dma(struct xsk_buff_pool *pool,
341 					      u64 addr)
342 {
343 	return 0;
344 }
345 
346 static inline void *xsk_buff_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
347 {
348 	return NULL;
349 }
350 
351 static inline bool xsk_buff_valid_tx_metadata(struct xsk_tx_metadata *meta)
352 {
353 	return false;
354 }
355 
356 static inline struct xsk_tx_metadata *xsk_buff_get_metadata(struct xsk_buff_pool *pool, u64 addr)
357 {
358 	return NULL;
359 }
360 
361 static inline void xsk_buff_dma_sync_for_cpu(struct xdp_buff *xdp, struct xsk_buff_pool *pool)
362 {
363 }
364 
365 static inline void xsk_buff_raw_dma_sync_for_device(struct xsk_buff_pool *pool,
366 						    dma_addr_t dma,
367 						    size_t size)
368 {
369 }
370 
371 #endif /* CONFIG_XDP_SOCKETS */
372 
373 #endif /* _LINUX_XDP_SOCK_DRV_H */
374