1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /* include/net/xdp.h
3 *
4 * Copyright (c) 2017 Jesper Dangaard Brouer, Red Hat Inc.
5 */
6 #ifndef __LINUX_NET_XDP_H__
7 #define __LINUX_NET_XDP_H__
8
9 #include <linux/bitfield.h>
10 #include <linux/filter.h>
11 #include <linux/netdevice.h>
12 #include <linux/skbuff.h> /* skb_shared_info */
13
14 #include <net/page_pool/types.h>
15
16 /**
17 * DOC: XDP RX-queue information
18 *
19 * The XDP RX-queue info (xdp_rxq_info) is associated with the driver
20 * level RX-ring queues. It is information that is specific to how
21 * the driver has configured a given RX-ring queue.
22 *
23 * Each xdp_buff frame received in the driver carries a (pointer)
24 * reference to this xdp_rxq_info structure. This provides the XDP
25 * data-path read-access to RX-info for both kernel and bpf-side
26 * (limited subset).
27 *
28 * For now, direct access is only safe while running in NAPI/softirq
29 * context. Contents are read-mostly and must not be updated during
30 * driver NAPI/softirq poll.
31 *
32 * The driver usage API is a register and unregister API.
33 *
34 * The struct is not directly tied to the XDP prog. A new XDP prog
35 * can be attached as long as it doesn't change the underlying
36 * RX-ring. If the RX-ring does change significantly, the NIC driver
37 * naturally needs to stop the RX-ring before purging and reallocating
38 * memory. In that process the driver MUST call unregister (which
39 * also applies for driver shutdown and unload). The register API is
40 * also mandatory during RX-ring setup.
41 */
42
43 enum xdp_mem_type {
44 MEM_TYPE_PAGE_SHARED = 0, /* Split-page refcnt based model */
45 MEM_TYPE_PAGE_ORDER0, /* Orig XDP full page model */
46 MEM_TYPE_PAGE_POOL,
47 MEM_TYPE_XSK_BUFF_POOL,
48 MEM_TYPE_MAX,
49 };
50
51 /* XDP flags for ndo_xdp_xmit */
52 #define XDP_XMIT_FLUSH (1U << 0) /* doorbell signal consumer */
53 #define XDP_XMIT_FLAGS_MASK XDP_XMIT_FLUSH
54
55 struct xdp_mem_info {
56 u32 type; /* enum xdp_mem_type, but known size type */
57 u32 id;
58 };
59
60 struct page_pool;
61
62 struct xdp_rxq_info {
63 struct net_device *dev;
64 u32 queue_index;
65 u32 reg_state;
66 struct xdp_mem_info mem;
67 u32 frag_size;
68 } ____cacheline_aligned; /* perf critical, avoid false-sharing */
69
70 struct xdp_txq_info {
71 struct net_device *dev;
72 };
73
74 enum xdp_buff_flags {
75 XDP_FLAGS_HAS_FRAGS = BIT(0), /* non-linear xdp buff */
76 XDP_FLAGS_FRAGS_PF_MEMALLOC = BIT(1), /* xdp paged memory is under
77 * pressure
78 */
79 /* frags have unreadable mem, this can't be true for real XDP packets,
80 * but drivers may use XDP helpers to construct Rx pkt state even when
81 * XDP program is not attached.
82 */
83 XDP_FLAGS_FRAGS_UNREADABLE = BIT(2),
84 };
85
86 struct xdp_buff {
87 void *data;
88 void *data_end;
89 void *data_meta;
90 void *data_hard_start;
91 struct xdp_rxq_info *rxq;
92 struct xdp_txq_info *txq;
93
94 union {
95 struct {
96 /* frame size to deduce data_hard_end/tailroom */
97 u32 frame_sz;
98 /* supported values defined in xdp_buff_flags */
99 u32 flags;
100 };
101
102 #ifdef __LITTLE_ENDIAN
103 /* Used to micro-optimize xdp_init_buff(), don't use directly */
104 u64 frame_sz_flags_init;
105 #endif
106 };
107 };
108
xdp_buff_has_frags(const struct xdp_buff * xdp)109 static __always_inline bool xdp_buff_has_frags(const struct xdp_buff *xdp)
110 {
111 return !!(xdp->flags & XDP_FLAGS_HAS_FRAGS);
112 }
113
xdp_buff_set_frags_flag(struct xdp_buff * xdp)114 static __always_inline void xdp_buff_set_frags_flag(struct xdp_buff *xdp)
115 {
116 xdp->flags |= XDP_FLAGS_HAS_FRAGS;
117 }
118
xdp_buff_clear_frags_flag(struct xdp_buff * xdp)119 static __always_inline void xdp_buff_clear_frags_flag(struct xdp_buff *xdp)
120 {
121 xdp->flags &= ~XDP_FLAGS_HAS_FRAGS;
122 }
123
xdp_buff_set_frag_pfmemalloc(struct xdp_buff * xdp)124 static __always_inline void xdp_buff_set_frag_pfmemalloc(struct xdp_buff *xdp)
125 {
126 xdp->flags |= XDP_FLAGS_FRAGS_PF_MEMALLOC;
127 }
128
xdp_buff_set_frag_unreadable(struct xdp_buff * xdp)129 static __always_inline void xdp_buff_set_frag_unreadable(struct xdp_buff *xdp)
130 {
131 xdp->flags |= XDP_FLAGS_FRAGS_UNREADABLE;
132 }
133
xdp_buff_get_skb_flags(const struct xdp_buff * xdp)134 static __always_inline u32 xdp_buff_get_skb_flags(const struct xdp_buff *xdp)
135 {
136 return xdp->flags;
137 }
138
xdp_buff_clear_frag_pfmemalloc(struct xdp_buff * xdp)139 static __always_inline void xdp_buff_clear_frag_pfmemalloc(struct xdp_buff *xdp)
140 {
141 xdp->flags &= ~XDP_FLAGS_FRAGS_PF_MEMALLOC;
142 }
143
144 static __always_inline void
xdp_init_buff(struct xdp_buff * xdp,u32 frame_sz,struct xdp_rxq_info * rxq)145 xdp_init_buff(struct xdp_buff *xdp, u32 frame_sz, struct xdp_rxq_info *rxq)
146 {
147 xdp->rxq = rxq;
148
149 #ifdef __LITTLE_ENDIAN
150 /*
151 * Force the compilers to initialize ::flags and assign ::frame_sz with
152 * one write on 64-bit LE architectures as they're often unable to do
153 * it themselves.
154 */
155 xdp->frame_sz_flags_init = frame_sz;
156 #else
157 xdp->frame_sz = frame_sz;
158 xdp->flags = 0;
159 #endif
160 }
161
162 static __always_inline void
xdp_prepare_buff(struct xdp_buff * xdp,unsigned char * hard_start,int headroom,int data_len,const bool meta_valid)163 xdp_prepare_buff(struct xdp_buff *xdp, unsigned char *hard_start,
164 int headroom, int data_len, const bool meta_valid)
165 {
166 unsigned char *data = hard_start + headroom;
167
168 xdp->data_hard_start = hard_start;
169 xdp->data = data;
170 xdp->data_end = data + data_len;
171 xdp->data_meta = meta_valid ? data : data + 1;
172 }
173
174 /* Reserve memory area at end-of data area.
175 *
176 * This macro reserves tailroom in the XDP buffer by limiting the
177 * XDP/BPF data access to data_hard_end. Notice same area (and size)
178 * is used for XDP_PASS, when constructing the SKB via build_skb().
179 */
180 #define xdp_data_hard_end(xdp) \
181 ((xdp)->data_hard_start + (xdp)->frame_sz - \
182 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
183
184 static inline struct skb_shared_info *
xdp_get_shared_info_from_buff(const struct xdp_buff * xdp)185 xdp_get_shared_info_from_buff(const struct xdp_buff *xdp)
186 {
187 return (struct skb_shared_info *)xdp_data_hard_end(xdp);
188 }
189
190 static __always_inline unsigned int
xdp_get_buff_len(const struct xdp_buff * xdp)191 xdp_get_buff_len(const struct xdp_buff *xdp)
192 {
193 unsigned int len = xdp->data_end - xdp->data;
194 const struct skb_shared_info *sinfo;
195
196 if (likely(!xdp_buff_has_frags(xdp)))
197 goto out;
198
199 sinfo = xdp_get_shared_info_from_buff(xdp);
200 len += sinfo->xdp_frags_size;
201 out:
202 return len;
203 }
204
205 void xdp_return_frag(netmem_ref netmem, const struct xdp_buff *xdp);
206
207 /**
208 * __xdp_buff_add_frag - attach frag to &xdp_buff
209 * @xdp: XDP buffer to attach the frag to
210 * @netmem: network memory containing the frag
211 * @offset: offset at which the frag starts
212 * @size: size of the frag
213 * @truesize: total memory size occupied by the frag
214 * @try_coalesce: whether to try coalescing the frags (not valid for XSk)
215 *
216 * Attach frag to the XDP buffer. If it currently has no frags attached,
217 * initialize the related fields, otherwise check that the frag number
218 * didn't reach the limit of ``MAX_SKB_FRAGS``. If possible, try coalescing
219 * the frag with the previous one.
220 * The function doesn't check/update the pfmemalloc bit. Please use the
221 * non-underscored wrapper in drivers.
222 *
223 * Return: true on success, false if there's no space for the frag in
224 * the shared info struct.
225 */
__xdp_buff_add_frag(struct xdp_buff * xdp,netmem_ref netmem,u32 offset,u32 size,u32 truesize,bool try_coalesce)226 static inline bool __xdp_buff_add_frag(struct xdp_buff *xdp, netmem_ref netmem,
227 u32 offset, u32 size, u32 truesize,
228 bool try_coalesce)
229 {
230 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
231 skb_frag_t *prev;
232 u32 nr_frags;
233
234 if (!xdp_buff_has_frags(xdp)) {
235 xdp_buff_set_frags_flag(xdp);
236
237 nr_frags = 0;
238 sinfo->xdp_frags_size = 0;
239 sinfo->xdp_frags_truesize = 0;
240
241 goto fill;
242 }
243
244 nr_frags = sinfo->nr_frags;
245 prev = &sinfo->frags[nr_frags - 1];
246
247 if (try_coalesce && netmem == skb_frag_netmem(prev) &&
248 offset == skb_frag_off(prev) + skb_frag_size(prev)) {
249 skb_frag_size_add(prev, size);
250 /* Guaranteed to only decrement the refcount */
251 xdp_return_frag(netmem, xdp);
252 } else if (unlikely(nr_frags == MAX_SKB_FRAGS)) {
253 return false;
254 } else {
255 fill:
256 __skb_fill_netmem_desc_noacc(sinfo, nr_frags++, netmem,
257 offset, size);
258 }
259
260 sinfo->nr_frags = nr_frags;
261 sinfo->xdp_frags_size += size;
262 sinfo->xdp_frags_truesize += truesize;
263
264 return true;
265 }
266
267 /**
268 * xdp_buff_add_frag - attach frag to &xdp_buff
269 * @xdp: XDP buffer to attach the frag to
270 * @netmem: network memory containing the frag
271 * @offset: offset at which the frag starts
272 * @size: size of the frag
273 * @truesize: total memory size occupied by the frag
274 *
275 * Version of __xdp_buff_add_frag() which takes care of the pfmemalloc bit.
276 *
277 * Return: true on success, false if there's no space for the frag in
278 * the shared info struct.
279 */
xdp_buff_add_frag(struct xdp_buff * xdp,netmem_ref netmem,u32 offset,u32 size,u32 truesize)280 static inline bool xdp_buff_add_frag(struct xdp_buff *xdp, netmem_ref netmem,
281 u32 offset, u32 size, u32 truesize)
282 {
283 if (!__xdp_buff_add_frag(xdp, netmem, offset, size, truesize, true))
284 return false;
285
286 if (unlikely(netmem_is_pfmemalloc(netmem)))
287 xdp_buff_set_frag_pfmemalloc(xdp);
288 if (unlikely(netmem_is_net_iov(netmem)))
289 xdp_buff_set_frag_unreadable(xdp);
290
291 return true;
292 }
293
294 struct xdp_frame {
295 void *data;
296 u32 len;
297 u32 headroom;
298 u32 metasize; /* uses lower 8-bits */
299 /* Lifetime of xdp_rxq_info is limited to NAPI/enqueue time,
300 * while mem_type is valid on remote CPU.
301 */
302 enum xdp_mem_type mem_type:32;
303 struct net_device *dev_rx; /* used by cpumap */
304 u32 frame_sz;
305 u32 flags; /* supported values defined in xdp_buff_flags */
306 };
307
xdp_frame_has_frags(const struct xdp_frame * frame)308 static __always_inline bool xdp_frame_has_frags(const struct xdp_frame *frame)
309 {
310 return !!(frame->flags & XDP_FLAGS_HAS_FRAGS);
311 }
312
313 static __always_inline u32
xdp_frame_get_skb_flags(const struct xdp_frame * frame)314 xdp_frame_get_skb_flags(const struct xdp_frame *frame)
315 {
316 return frame->flags;
317 }
318
319 #define XDP_BULK_QUEUE_SIZE 16
320 struct xdp_frame_bulk {
321 int count;
322 netmem_ref q[XDP_BULK_QUEUE_SIZE];
323 };
324
xdp_frame_bulk_init(struct xdp_frame_bulk * bq)325 static __always_inline void xdp_frame_bulk_init(struct xdp_frame_bulk *bq)
326 {
327 bq->count = 0;
328 }
329
330 static inline struct skb_shared_info *
xdp_get_shared_info_from_frame(const struct xdp_frame * frame)331 xdp_get_shared_info_from_frame(const struct xdp_frame *frame)
332 {
333 void *data_hard_start = frame->data - frame->headroom - sizeof(*frame);
334
335 return (struct skb_shared_info *)(data_hard_start + frame->frame_sz -
336 SKB_DATA_ALIGN(sizeof(struct skb_shared_info)));
337 }
338
339 struct xdp_cpumap_stats {
340 unsigned int redirect;
341 unsigned int pass;
342 unsigned int drop;
343 };
344
345 /* Clear kernel pointers in xdp_frame */
xdp_scrub_frame(struct xdp_frame * frame)346 static inline void xdp_scrub_frame(struct xdp_frame *frame)
347 {
348 frame->data = NULL;
349 frame->dev_rx = NULL;
350 }
351
352 static inline void
xdp_update_skb_frags_info(struct sk_buff * skb,u8 nr_frags,unsigned int size,unsigned int truesize,u32 xdp_flags)353 xdp_update_skb_frags_info(struct sk_buff *skb, u8 nr_frags,
354 unsigned int size, unsigned int truesize,
355 u32 xdp_flags)
356 {
357 struct skb_shared_info *sinfo = skb_shinfo(skb);
358
359 sinfo->nr_frags = nr_frags;
360 /*
361 * ``destructor_arg`` is unionized with ``xdp_frags_{,true}size``,
362 * reset it after that these fields aren't used anymore.
363 */
364 sinfo->destructor_arg = NULL;
365
366 skb->len += size;
367 skb->data_len += size;
368 skb->truesize += truesize;
369 skb->pfmemalloc |= !!(xdp_flags & XDP_FLAGS_FRAGS_PF_MEMALLOC);
370 skb->unreadable |= !!(xdp_flags & XDP_FLAGS_FRAGS_UNREADABLE);
371 }
372
373 /* Avoids inlining WARN macro in fast-path */
374 void xdp_warn(const char *msg, const char *func, const int line);
375 #define XDP_WARN(msg) xdp_warn(msg, __func__, __LINE__)
376
377 struct sk_buff *xdp_build_skb_from_buff(const struct xdp_buff *xdp);
378 struct sk_buff *xdp_build_skb_from_zc(struct xdp_buff *xdp);
379 struct xdp_frame *xdp_convert_zc_to_xdp_frame(struct xdp_buff *xdp);
380 struct sk_buff *__xdp_build_skb_from_frame(struct xdp_frame *xdpf,
381 struct sk_buff *skb,
382 struct net_device *dev);
383 struct sk_buff *xdp_build_skb_from_frame(struct xdp_frame *xdpf,
384 struct net_device *dev);
385 struct xdp_frame *xdpf_clone(struct xdp_frame *xdpf);
386
387 static inline
xdp_convert_frame_to_buff(const struct xdp_frame * frame,struct xdp_buff * xdp)388 void xdp_convert_frame_to_buff(const struct xdp_frame *frame,
389 struct xdp_buff *xdp)
390 {
391 xdp->data_hard_start = frame->data - frame->headroom - sizeof(*frame);
392 xdp->data = frame->data;
393 xdp->data_end = frame->data + frame->len;
394 xdp->data_meta = frame->data - frame->metasize;
395 xdp->frame_sz = frame->frame_sz;
396 xdp->flags = frame->flags;
397 }
398
399 static inline
xdp_update_frame_from_buff(const struct xdp_buff * xdp,struct xdp_frame * xdp_frame)400 int xdp_update_frame_from_buff(const struct xdp_buff *xdp,
401 struct xdp_frame *xdp_frame)
402 {
403 int metasize, headroom;
404
405 /* Assure headroom is available for storing info */
406 headroom = xdp->data - xdp->data_hard_start;
407 metasize = xdp->data - xdp->data_meta;
408 metasize = metasize > 0 ? metasize : 0;
409 if (unlikely((headroom - metasize) < sizeof(*xdp_frame)))
410 return -ENOSPC;
411
412 /* Catch if driver didn't reserve tailroom for skb_shared_info */
413 if (unlikely(xdp->data_end > xdp_data_hard_end(xdp))) {
414 XDP_WARN("Driver BUG: missing reserved tailroom");
415 return -ENOSPC;
416 }
417
418 xdp_frame->data = xdp->data;
419 xdp_frame->len = xdp->data_end - xdp->data;
420 xdp_frame->headroom = headroom - sizeof(*xdp_frame);
421 xdp_frame->metasize = metasize;
422 xdp_frame->frame_sz = xdp->frame_sz;
423 xdp_frame->flags = xdp->flags;
424
425 return 0;
426 }
427
428 /* Convert xdp_buff to xdp_frame */
429 static inline
xdp_convert_buff_to_frame(struct xdp_buff * xdp)430 struct xdp_frame *xdp_convert_buff_to_frame(struct xdp_buff *xdp)
431 {
432 struct xdp_frame *xdp_frame;
433
434 if (xdp->rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL)
435 return xdp_convert_zc_to_xdp_frame(xdp);
436
437 /* Store info in top of packet */
438 xdp_frame = xdp->data_hard_start;
439 if (unlikely(xdp_update_frame_from_buff(xdp, xdp_frame) < 0))
440 return NULL;
441
442 /* rxq only valid until napi_schedule ends, convert to xdp_mem_type */
443 xdp_frame->mem_type = xdp->rxq->mem.type;
444
445 return xdp_frame;
446 }
447
448 void __xdp_return(netmem_ref netmem, enum xdp_mem_type mem_type,
449 bool napi_direct, struct xdp_buff *xdp);
450 void xdp_return_frame(struct xdp_frame *xdpf);
451 void xdp_return_frame_rx_napi(struct xdp_frame *xdpf);
452 void xdp_return_buff(struct xdp_buff *xdp);
453 void xdp_return_frame_bulk(struct xdp_frame *xdpf,
454 struct xdp_frame_bulk *bq);
455
xdp_flush_frame_bulk(struct xdp_frame_bulk * bq)456 static inline void xdp_flush_frame_bulk(struct xdp_frame_bulk *bq)
457 {
458 if (unlikely(!bq->count))
459 return;
460
461 page_pool_put_netmem_bulk(bq->q, bq->count);
462 bq->count = 0;
463 }
464
465 static __always_inline unsigned int
xdp_get_frame_len(const struct xdp_frame * xdpf)466 xdp_get_frame_len(const struct xdp_frame *xdpf)
467 {
468 const struct skb_shared_info *sinfo;
469 unsigned int len = xdpf->len;
470
471 if (likely(!xdp_frame_has_frags(xdpf)))
472 goto out;
473
474 sinfo = xdp_get_shared_info_from_frame(xdpf);
475 len += sinfo->xdp_frags_size;
476 out:
477 return len;
478 }
479
480 int __xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
481 struct net_device *dev, u32 queue_index,
482 unsigned int napi_id, u32 frag_size);
483 static inline int
xdp_rxq_info_reg(struct xdp_rxq_info * xdp_rxq,struct net_device * dev,u32 queue_index,unsigned int napi_id)484 xdp_rxq_info_reg(struct xdp_rxq_info *xdp_rxq,
485 struct net_device *dev, u32 queue_index,
486 unsigned int napi_id)
487 {
488 return __xdp_rxq_info_reg(xdp_rxq, dev, queue_index, napi_id, 0);
489 }
490
491 void xdp_rxq_info_unreg(struct xdp_rxq_info *xdp_rxq);
492 void xdp_rxq_info_unused(struct xdp_rxq_info *xdp_rxq);
493 bool xdp_rxq_info_is_reg(struct xdp_rxq_info *xdp_rxq);
494 int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq,
495 enum xdp_mem_type type, void *allocator);
496 void xdp_rxq_info_unreg_mem_model(struct xdp_rxq_info *xdp_rxq);
497 int xdp_reg_mem_model(struct xdp_mem_info *mem,
498 enum xdp_mem_type type, void *allocator);
499 void xdp_unreg_mem_model(struct xdp_mem_info *mem);
500 int xdp_reg_page_pool(struct page_pool *pool);
501 void xdp_unreg_page_pool(const struct page_pool *pool);
502 void xdp_rxq_info_attach_page_pool(struct xdp_rxq_info *xdp_rxq,
503 const struct page_pool *pool);
504
505 /**
506 * xdp_rxq_info_attach_mem_model - attach registered mem info to RxQ info
507 * @xdp_rxq: XDP RxQ info to attach the memory info to
508 * @mem: already registered memory info
509 *
510 * If the driver registers its memory providers manually, it must use this
511 * function instead of xdp_rxq_info_reg_mem_model().
512 */
513 static inline void
xdp_rxq_info_attach_mem_model(struct xdp_rxq_info * xdp_rxq,const struct xdp_mem_info * mem)514 xdp_rxq_info_attach_mem_model(struct xdp_rxq_info *xdp_rxq,
515 const struct xdp_mem_info *mem)
516 {
517 xdp_rxq->mem = *mem;
518 }
519
520 /**
521 * xdp_rxq_info_detach_mem_model - detach registered mem info from RxQ info
522 * @xdp_rxq: XDP RxQ info to detach the memory info from
523 *
524 * If the driver registers its memory providers manually and then attaches it
525 * via xdp_rxq_info_attach_mem_model(), it must call this function before
526 * xdp_rxq_info_unreg().
527 */
xdp_rxq_info_detach_mem_model(struct xdp_rxq_info * xdp_rxq)528 static inline void xdp_rxq_info_detach_mem_model(struct xdp_rxq_info *xdp_rxq)
529 {
530 xdp_rxq->mem = (struct xdp_mem_info){ };
531 }
532
533 /* Drivers not supporting XDP metadata can use this helper, which
534 * rejects any room expansion for metadata as a result.
535 */
536 static __always_inline void
xdp_set_data_meta_invalid(struct xdp_buff * xdp)537 xdp_set_data_meta_invalid(struct xdp_buff *xdp)
538 {
539 xdp->data_meta = xdp->data + 1;
540 }
541
542 static __always_inline bool
xdp_data_meta_unsupported(const struct xdp_buff * xdp)543 xdp_data_meta_unsupported(const struct xdp_buff *xdp)
544 {
545 return unlikely(xdp->data_meta > xdp->data);
546 }
547
xdp_metalen_invalid(unsigned long metalen)548 static inline bool xdp_metalen_invalid(unsigned long metalen)
549 {
550 unsigned long meta_max;
551
552 meta_max = type_max(typeof_member(struct skb_shared_info, meta_len));
553 BUILD_BUG_ON(!__builtin_constant_p(meta_max));
554
555 return !IS_ALIGNED(metalen, sizeof(u32)) || metalen > meta_max;
556 }
557
558 struct xdp_attachment_info {
559 struct bpf_prog *prog;
560 u32 flags;
561 };
562
563 struct netdev_bpf;
564 void xdp_attachment_setup(struct xdp_attachment_info *info,
565 struct netdev_bpf *bpf);
566
567 #define DEV_MAP_BULK_SIZE XDP_BULK_QUEUE_SIZE
568
569 /* Define the relationship between xdp-rx-metadata kfunc and
570 * various other entities:
571 * - xdp_rx_metadata enum
572 * - netdev netlink enum (Documentation/netlink/specs/netdev.yaml)
573 * - kfunc name
574 * - xdp_metadata_ops field
575 */
576 #define XDP_METADATA_KFUNC_xxx \
577 XDP_METADATA_KFUNC(XDP_METADATA_KFUNC_RX_TIMESTAMP, \
578 NETDEV_XDP_RX_METADATA_TIMESTAMP, \
579 bpf_xdp_metadata_rx_timestamp, \
580 xmo_rx_timestamp) \
581 XDP_METADATA_KFUNC(XDP_METADATA_KFUNC_RX_HASH, \
582 NETDEV_XDP_RX_METADATA_HASH, \
583 bpf_xdp_metadata_rx_hash, \
584 xmo_rx_hash) \
585 XDP_METADATA_KFUNC(XDP_METADATA_KFUNC_RX_VLAN_TAG, \
586 NETDEV_XDP_RX_METADATA_VLAN_TAG, \
587 bpf_xdp_metadata_rx_vlan_tag, \
588 xmo_rx_vlan_tag) \
589
590 enum xdp_rx_metadata {
591 #define XDP_METADATA_KFUNC(name, _, __, ___) name,
592 XDP_METADATA_KFUNC_xxx
593 #undef XDP_METADATA_KFUNC
594 MAX_XDP_METADATA_KFUNC,
595 };
596
597 enum xdp_rss_hash_type {
598 /* First part: Individual bits for L3/L4 types */
599 XDP_RSS_L3_IPV4 = BIT(0),
600 XDP_RSS_L3_IPV6 = BIT(1),
601
602 /* The fixed (L3) IPv4 and IPv6 headers can both be followed by
603 * variable/dynamic headers, IPv4 called Options and IPv6 called
604 * Extension Headers. HW RSS type can contain this info.
605 */
606 XDP_RSS_L3_DYNHDR = BIT(2),
607
608 /* When RSS hash covers L4 then drivers MUST set XDP_RSS_L4 bit in
609 * addition to the protocol specific bit. This ease interaction with
610 * SKBs and avoids reserving a fixed mask for future L4 protocol bits.
611 */
612 XDP_RSS_L4 = BIT(3), /* L4 based hash, proto can be unknown */
613 XDP_RSS_L4_TCP = BIT(4),
614 XDP_RSS_L4_UDP = BIT(5),
615 XDP_RSS_L4_SCTP = BIT(6),
616 XDP_RSS_L4_IPSEC = BIT(7), /* L4 based hash include IPSEC SPI */
617 XDP_RSS_L4_ICMP = BIT(8),
618
619 /* Second part: RSS hash type combinations used for driver HW mapping */
620 XDP_RSS_TYPE_NONE = 0,
621 XDP_RSS_TYPE_L2 = XDP_RSS_TYPE_NONE,
622
623 XDP_RSS_TYPE_L3_IPV4 = XDP_RSS_L3_IPV4,
624 XDP_RSS_TYPE_L3_IPV6 = XDP_RSS_L3_IPV6,
625 XDP_RSS_TYPE_L3_IPV4_OPT = XDP_RSS_L3_IPV4 | XDP_RSS_L3_DYNHDR,
626 XDP_RSS_TYPE_L3_IPV6_EX = XDP_RSS_L3_IPV6 | XDP_RSS_L3_DYNHDR,
627
628 XDP_RSS_TYPE_L4_ANY = XDP_RSS_L4,
629 XDP_RSS_TYPE_L4_IPV4_TCP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_TCP,
630 XDP_RSS_TYPE_L4_IPV4_UDP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_UDP,
631 XDP_RSS_TYPE_L4_IPV4_SCTP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_SCTP,
632 XDP_RSS_TYPE_L4_IPV4_IPSEC = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_IPSEC,
633 XDP_RSS_TYPE_L4_IPV4_ICMP = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_ICMP,
634
635 XDP_RSS_TYPE_L4_IPV6_TCP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_TCP,
636 XDP_RSS_TYPE_L4_IPV6_UDP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_UDP,
637 XDP_RSS_TYPE_L4_IPV6_SCTP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_SCTP,
638 XDP_RSS_TYPE_L4_IPV6_IPSEC = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_IPSEC,
639 XDP_RSS_TYPE_L4_IPV6_ICMP = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_ICMP,
640
641 XDP_RSS_TYPE_L4_IPV6_TCP_EX = XDP_RSS_TYPE_L4_IPV6_TCP | XDP_RSS_L3_DYNHDR,
642 XDP_RSS_TYPE_L4_IPV6_UDP_EX = XDP_RSS_TYPE_L4_IPV6_UDP | XDP_RSS_L3_DYNHDR,
643 XDP_RSS_TYPE_L4_IPV6_SCTP_EX = XDP_RSS_TYPE_L4_IPV6_SCTP | XDP_RSS_L3_DYNHDR,
644 };
645
646 struct xdp_metadata_ops {
647 int (*xmo_rx_timestamp)(const struct xdp_md *ctx, u64 *timestamp);
648 int (*xmo_rx_hash)(const struct xdp_md *ctx, u32 *hash,
649 enum xdp_rss_hash_type *rss_type);
650 int (*xmo_rx_vlan_tag)(const struct xdp_md *ctx, __be16 *vlan_proto,
651 u16 *vlan_tci);
652 };
653
654 #ifdef CONFIG_NET
655 u32 bpf_xdp_metadata_kfunc_id(int id);
656 bool bpf_dev_bound_kfunc_id(u32 btf_id);
657 void xdp_set_features_flag(struct net_device *dev, xdp_features_t val);
658 void xdp_set_features_flag_locked(struct net_device *dev, xdp_features_t val);
659 void xdp_features_set_redirect_target(struct net_device *dev, bool support_sg);
660 void xdp_features_set_redirect_target_locked(struct net_device *dev,
661 bool support_sg);
662 void xdp_features_clear_redirect_target(struct net_device *dev);
663 void xdp_features_clear_redirect_target_locked(struct net_device *dev);
664 #else
bpf_xdp_metadata_kfunc_id(int id)665 static inline u32 bpf_xdp_metadata_kfunc_id(int id) { return 0; }
bpf_dev_bound_kfunc_id(u32 btf_id)666 static inline bool bpf_dev_bound_kfunc_id(u32 btf_id) { return false; }
667
668 static inline void
xdp_set_features_flag(struct net_device * dev,xdp_features_t val)669 xdp_set_features_flag(struct net_device *dev, xdp_features_t val)
670 {
671 }
672
673 static inline void
xdp_features_set_redirect_target(struct net_device * dev,bool support_sg)674 xdp_features_set_redirect_target(struct net_device *dev, bool support_sg)
675 {
676 }
677
678 static inline void
xdp_features_clear_redirect_target(struct net_device * dev)679 xdp_features_clear_redirect_target(struct net_device *dev)
680 {
681 }
682 #endif
683
xdp_clear_features_flag(struct net_device * dev)684 static inline void xdp_clear_features_flag(struct net_device *dev)
685 {
686 xdp_set_features_flag(dev, 0);
687 }
688
bpf_prog_run_xdp(const struct bpf_prog * prog,struct xdp_buff * xdp)689 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,
690 struct xdp_buff *xdp)
691 {
692 /* Driver XDP hooks are invoked within a single NAPI poll cycle and thus
693 * under local_bh_disable(), which provides the needed RCU protection
694 * for accessing map entries.
695 */
696 u32 act = __bpf_prog_run(prog, xdp, BPF_DISPATCHER_FUNC(xdp));
697
698 if (static_branch_unlikely(&bpf_master_redirect_enabled_key)) {
699 if (act == XDP_TX && netif_is_bond_slave(xdp->rxq->dev))
700 act = xdp_master_redirect(xdp);
701 }
702
703 return act;
704 }
705 #endif /* __LINUX_NET_XDP_H__ */
706