xref: /linux/include/net/xdp_sock_drv.h (revision a634dda26186cf9a51567020fcce52bcba5e1e59) 
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 struct xsk_cb_desc {
16 	void *src;
17 	u8 off;
18 	u8 bytes;
19 };
20 
21 #ifdef CONFIG_XDP_SOCKETS
22 
23 void xsk_tx_completed(struct xsk_buff_pool *pool, u32 nb_entries);
24 bool xsk_tx_peek_desc(struct xsk_buff_pool *pool, struct xdp_desc *desc);
25 u32 xsk_tx_peek_release_desc_batch(struct xsk_buff_pool *pool, u32 max);
26 void xsk_tx_release(struct xsk_buff_pool *pool);
27 struct xsk_buff_pool *xsk_get_pool_from_qid(struct net_device *dev,
28 					    u16 queue_id);
29 void xsk_set_rx_need_wakeup(struct xsk_buff_pool *pool);
30 void xsk_set_tx_need_wakeup(struct xsk_buff_pool *pool);
31 void xsk_clear_rx_need_wakeup(struct xsk_buff_pool *pool);
32 void xsk_clear_tx_need_wakeup(struct xsk_buff_pool *pool);
33 bool xsk_uses_need_wakeup(struct xsk_buff_pool *pool);
34 
35 static inline u32 xsk_pool_get_headroom(struct xsk_buff_pool *pool)
36 {
37 	return XDP_PACKET_HEADROOM + pool->headroom;
38 }
39 
40 static inline u32 xsk_pool_get_chunk_size(struct xsk_buff_pool *pool)
41 {
42 	return pool->chunk_size;
43 }
44 
45 static inline u32 xsk_pool_get_rx_frame_size(struct xsk_buff_pool *pool)
46 {
47 	return xsk_pool_get_chunk_size(pool) - xsk_pool_get_headroom(pool);
48 }
49 
50 static inline void xsk_pool_set_rxq_info(struct xsk_buff_pool *pool,
51 					 struct xdp_rxq_info *rxq)
52 {
53 	xp_set_rxq_info(pool, rxq);
54 }
55 
56 static inline void xsk_pool_fill_cb(struct xsk_buff_pool *pool,
57 				    struct xsk_cb_desc *desc)
58 {
59 	xp_fill_cb(pool, desc);
60 }
61 
62 static inline void xsk_pool_dma_unmap(struct xsk_buff_pool *pool,
63 				      unsigned long attrs)
64 {
65 	xp_dma_unmap(pool, attrs);
66 }
67 
68 static inline int xsk_pool_dma_map(struct xsk_buff_pool *pool,
69 				   struct device *dev, unsigned long attrs)
70 {
71 	struct xdp_umem *umem = pool->umem;
72 
73 	return xp_dma_map(pool, dev, attrs, umem->pgs, umem->npgs);
74 }
75 
76 static inline dma_addr_t xsk_buff_xdp_get_dma(struct xdp_buff *xdp)
77 {
78 	struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
79 
80 	return xp_get_dma(xskb);
81 }
82 
83 static inline dma_addr_t xsk_buff_xdp_get_frame_dma(struct xdp_buff *xdp)
84 {
85 	struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
86 
87 	return xp_get_frame_dma(xskb);
88 }
89 
90 static inline struct xdp_buff *xsk_buff_alloc(struct xsk_buff_pool *pool)
91 {
92 	return xp_alloc(pool);
93 }
94 
95 static inline bool xsk_is_eop_desc(struct xdp_desc *desc)
96 {
97 	return !xp_mb_desc(desc);
98 }
99 
100 /* Returns as many entries as possible up to max. 0 <= N <= max. */
101 static inline u32 xsk_buff_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
102 {
103 	return xp_alloc_batch(pool, xdp, max);
104 }
105 
106 static inline bool xsk_buff_can_alloc(struct xsk_buff_pool *pool, u32 count)
107 {
108 	return xp_can_alloc(pool, count);
109 }
110 
111 static inline void xsk_buff_free(struct xdp_buff *xdp)
112 {
113 	struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
114 	struct list_head *xskb_list = &xskb->pool->xskb_list;
115 	struct xdp_buff_xsk *pos, *tmp;
116 
117 	if (likely(!xdp_buff_has_frags(xdp)))
118 		goto out;
119 
120 	list_for_each_entry_safe(pos, tmp, xskb_list, list_node) {
121 		list_del(&pos->list_node);
122 		xp_free(pos);
123 	}
124 
125 	xdp_get_shared_info_from_buff(xdp)->nr_frags = 0;
126 out:
127 	xp_free(xskb);
128 }
129 
130 static inline void xsk_buff_add_frag(struct xdp_buff *xdp)
131 {
132 	struct xdp_buff_xsk *frag = container_of(xdp, struct xdp_buff_xsk, xdp);
133 
134 	list_add_tail(&frag->list_node, &frag->pool->xskb_list);
135 }
136 
137 static inline struct xdp_buff *xsk_buff_get_frag(struct xdp_buff *first)
138 {
139 	struct xdp_buff_xsk *xskb = container_of(first, struct xdp_buff_xsk, xdp);
140 	struct xdp_buff *ret = NULL;
141 	struct xdp_buff_xsk *frag;
142 
143 	frag = list_first_entry_or_null(&xskb->pool->xskb_list,
144 					struct xdp_buff_xsk, list_node);
145 	if (frag) {
146 		list_del(&frag->list_node);
147 		ret = &frag->xdp;
148 	}
149 
150 	return ret;
151 }
152 
153 static inline void xsk_buff_del_tail(struct xdp_buff *tail)
154 {
155 	struct xdp_buff_xsk *xskb = container_of(tail, struct xdp_buff_xsk, xdp);
156 
157 	list_del(&xskb->list_node);
158 }
159 
160 static inline struct xdp_buff *xsk_buff_get_tail(struct xdp_buff *first)
161 {
162 	struct xdp_buff_xsk *xskb = container_of(first, struct xdp_buff_xsk, xdp);
163 	struct xdp_buff_xsk *frag;
164 
165 	frag = list_last_entry(&xskb->pool->xskb_list, struct xdp_buff_xsk,
166 			       list_node);
167 	return &frag->xdp;
168 }
169 
170 static inline void xsk_buff_set_size(struct xdp_buff *xdp, u32 size)
171 {
172 	xdp->data = xdp->data_hard_start + XDP_PACKET_HEADROOM;
173 	xdp->data_meta = xdp->data;
174 	xdp->data_end = xdp->data + size;
175 	xdp->flags = 0;
176 }
177 
178 static inline dma_addr_t xsk_buff_raw_get_dma(struct xsk_buff_pool *pool,
179 					      u64 addr)
180 {
181 	return xp_raw_get_dma(pool, addr);
182 }
183 
184 static inline void *xsk_buff_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
185 {
186 	return xp_raw_get_data(pool, addr);
187 }
188 
189 #define XDP_TXMD_FLAGS_VALID ( \
190 		XDP_TXMD_FLAGS_TIMESTAMP | \
191 		XDP_TXMD_FLAGS_CHECKSUM | \
192 	0)
193 
194 static inline bool xsk_buff_valid_tx_metadata(struct xsk_tx_metadata *meta)
195 {
196 	return !(meta->flags & ~XDP_TXMD_FLAGS_VALID);
197 }
198 
199 static inline struct xsk_tx_metadata *xsk_buff_get_metadata(struct xsk_buff_pool *pool, u64 addr)
200 {
201 	struct xsk_tx_metadata *meta;
202 
203 	if (!pool->tx_metadata_len)
204 		return NULL;
205 
206 	meta = xp_raw_get_data(pool, addr) - pool->tx_metadata_len;
207 	if (unlikely(!xsk_buff_valid_tx_metadata(meta)))
208 		return NULL; /* no way to signal the error to the user */
209 
210 	return meta;
211 }
212 
213 static inline void xsk_buff_dma_sync_for_cpu(struct xdp_buff *xdp)
214 {
215 	struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
216 
217 	xp_dma_sync_for_cpu(xskb);
218 }
219 
220 static inline void xsk_buff_raw_dma_sync_for_device(struct xsk_buff_pool *pool,
221 						    dma_addr_t dma,
222 						    size_t size)
223 {
224 	xp_dma_sync_for_device(pool, dma, size);
225 }
226 
227 #else
228 
229 static inline void xsk_tx_completed(struct xsk_buff_pool *pool, u32 nb_entries)
230 {
231 }
232 
233 static inline bool xsk_tx_peek_desc(struct xsk_buff_pool *pool,
234 				    struct xdp_desc *desc)
235 {
236 	return false;
237 }
238 
239 static inline u32 xsk_tx_peek_release_desc_batch(struct xsk_buff_pool *pool, u32 max)
240 {
241 	return 0;
242 }
243 
244 static inline void xsk_tx_release(struct xsk_buff_pool *pool)
245 {
246 }
247 
248 static inline struct xsk_buff_pool *
249 xsk_get_pool_from_qid(struct net_device *dev, u16 queue_id)
250 {
251 	return NULL;
252 }
253 
254 static inline void xsk_set_rx_need_wakeup(struct xsk_buff_pool *pool)
255 {
256 }
257 
258 static inline void xsk_set_tx_need_wakeup(struct xsk_buff_pool *pool)
259 {
260 }
261 
262 static inline void xsk_clear_rx_need_wakeup(struct xsk_buff_pool *pool)
263 {
264 }
265 
266 static inline void xsk_clear_tx_need_wakeup(struct xsk_buff_pool *pool)
267 {
268 }
269 
270 static inline bool xsk_uses_need_wakeup(struct xsk_buff_pool *pool)
271 {
272 	return false;
273 }
274 
275 static inline u32 xsk_pool_get_headroom(struct xsk_buff_pool *pool)
276 {
277 	return 0;
278 }
279 
280 static inline u32 xsk_pool_get_chunk_size(struct xsk_buff_pool *pool)
281 {
282 	return 0;
283 }
284 
285 static inline u32 xsk_pool_get_rx_frame_size(struct xsk_buff_pool *pool)
286 {
287 	return 0;
288 }
289 
290 static inline void xsk_pool_set_rxq_info(struct xsk_buff_pool *pool,
291 					 struct xdp_rxq_info *rxq)
292 {
293 }
294 
295 static inline void xsk_pool_fill_cb(struct xsk_buff_pool *pool,
296 				    struct xsk_cb_desc *desc)
297 {
298 }
299 
300 static inline void xsk_pool_dma_unmap(struct xsk_buff_pool *pool,
301 				      unsigned long attrs)
302 {
303 }
304 
305 static inline int xsk_pool_dma_map(struct xsk_buff_pool *pool,
306 				   struct device *dev, unsigned long attrs)
307 {
308 	return 0;
309 }
310 
311 static inline dma_addr_t xsk_buff_xdp_get_dma(struct xdp_buff *xdp)
312 {
313 	return 0;
314 }
315 
316 static inline dma_addr_t xsk_buff_xdp_get_frame_dma(struct xdp_buff *xdp)
317 {
318 	return 0;
319 }
320 
321 static inline struct xdp_buff *xsk_buff_alloc(struct xsk_buff_pool *pool)
322 {
323 	return NULL;
324 }
325 
326 static inline bool xsk_is_eop_desc(struct xdp_desc *desc)
327 {
328 	return false;
329 }
330 
331 static inline u32 xsk_buff_alloc_batch(struct xsk_buff_pool *pool, struct xdp_buff **xdp, u32 max)
332 {
333 	return 0;
334 }
335 
336 static inline bool xsk_buff_can_alloc(struct xsk_buff_pool *pool, u32 count)
337 {
338 	return false;
339 }
340 
341 static inline void xsk_buff_free(struct xdp_buff *xdp)
342 {
343 }
344 
345 static inline void xsk_buff_add_frag(struct xdp_buff *xdp)
346 {
347 }
348 
349 static inline struct xdp_buff *xsk_buff_get_frag(struct xdp_buff *first)
350 {
351 	return NULL;
352 }
353 
354 static inline void xsk_buff_del_tail(struct xdp_buff *tail)
355 {
356 }
357 
358 static inline struct xdp_buff *xsk_buff_get_tail(struct xdp_buff *first)
359 {
360 	return NULL;
361 }
362 
363 static inline void xsk_buff_set_size(struct xdp_buff *xdp, u32 size)
364 {
365 }
366 
367 static inline dma_addr_t xsk_buff_raw_get_dma(struct xsk_buff_pool *pool,
368 					      u64 addr)
369 {
370 	return 0;
371 }
372 
373 static inline void *xsk_buff_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
374 {
375 	return NULL;
376 }
377 
378 static inline bool xsk_buff_valid_tx_metadata(struct xsk_tx_metadata *meta)
379 {
380 	return false;
381 }
382 
383 static inline struct xsk_tx_metadata *xsk_buff_get_metadata(struct xsk_buff_pool *pool, u64 addr)
384 {
385 	return NULL;
386 }
387 
388 static inline void xsk_buff_dma_sync_for_cpu(struct xdp_buff *xdp)
389 {
390 }
391 
392 static inline void xsk_buff_raw_dma_sync_for_device(struct xsk_buff_pool *pool,
393 						    dma_addr_t dma,
394 						    size_t size)
395 {
396 }
397 
398 #endif /* CONFIG_XDP_SOCKETS */
399 
400 #endif /* _LINUX_XDP_SOCK_DRV_H */
401