1 /*
2  * Copyright (c) 2018, Mellanox Technologies. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/bpf_trace.h>
34 #include <net/xdp_sock_drv.h>
35 #include "en/xdp.h"
36 #include "en/params.h"
37 #include <linux/bitfield.h>
38 
39 int mlx5e_xdp_max_mtu(struct mlx5e_params *params, struct mlx5e_xsk_param *xsk)
40 {
41 	int hr = mlx5e_get_linear_rq_headroom(params, xsk);
42 
43 	/* Let S := SKB_DATA_ALIGN(sizeof(struct skb_shared_info)).
44 	 * The condition checked in mlx5e_rx_is_linear_skb is:
45 	 *   SKB_DATA_ALIGN(sw_mtu + hard_mtu + hr) + S <= PAGE_SIZE         (1)
46 	 *   (Note that hw_mtu == sw_mtu + hard_mtu.)
47 	 * What is returned from this function is:
48 	 *   max_mtu = PAGE_SIZE - S - hr - hard_mtu                         (2)
49 	 * After assigning sw_mtu := max_mtu, the left side of (1) turns to
50 	 * SKB_DATA_ALIGN(PAGE_SIZE - S) + S, which is equal to PAGE_SIZE,
51 	 * because both PAGE_SIZE and S are already aligned. Any number greater
52 	 * than max_mtu would make the left side of (1) greater than PAGE_SIZE,
53 	 * so max_mtu is the maximum MTU allowed.
54 	 */
55 
56 	return MLX5E_HW2SW_MTU(params, SKB_MAX_HEAD(hr));
57 }
58 
59 static inline bool
60 mlx5e_xmit_xdp_buff(struct mlx5e_xdpsq *sq, struct mlx5e_rq *rq,
61 		    struct xdp_buff *xdp)
62 {
63 	struct page *page = virt_to_page(xdp->data);
64 	struct mlx5e_xmit_data_frags xdptxdf = {};
65 	struct mlx5e_xmit_data *xdptxd;
66 	struct xdp_frame *xdpf;
67 	dma_addr_t dma_addr;
68 	int i;
69 
70 	xdpf = xdp_convert_buff_to_frame(xdp);
71 	if (unlikely(!xdpf))
72 		return false;
73 
74 	xdptxd = &xdptxdf.xd;
75 	xdptxd->data = xdpf->data;
76 	xdptxd->len  = xdpf->len;
77 	xdptxd->has_frags = xdp_frame_has_frags(xdpf);
78 
79 	if (xdp->rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL) {
80 		/* The xdp_buff was in the UMEM and was copied into a newly
81 		 * allocated page. The UMEM page was returned via the ZCA, and
82 		 * this new page has to be mapped at this point and has to be
83 		 * unmapped and returned via xdp_return_frame on completion.
84 		 */
85 
86 		/* Prevent double recycling of the UMEM page. Even in case this
87 		 * function returns false, the xdp_buff shouldn't be recycled,
88 		 * as it was already done in xdp_convert_zc_to_xdp_frame.
89 		 */
90 		__set_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags); /* non-atomic */
91 
92 		if (unlikely(xdptxd->has_frags))
93 			return false;
94 
95 		dma_addr = dma_map_single(sq->pdev, xdptxd->data, xdptxd->len,
96 					  DMA_TO_DEVICE);
97 		if (dma_mapping_error(sq->pdev, dma_addr)) {
98 			xdp_return_frame(xdpf);
99 			return false;
100 		}
101 
102 		xdptxd->dma_addr = dma_addr;
103 
104 		if (unlikely(!INDIRECT_CALL_2(sq->xmit_xdp_frame, mlx5e_xmit_xdp_frame_mpwqe,
105 					      mlx5e_xmit_xdp_frame, sq, xdptxd, 0)))
106 			return false;
107 
108 		/* xmit_mode == MLX5E_XDP_XMIT_MODE_FRAME */
109 		mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
110 				     (union mlx5e_xdp_info) { .mode = MLX5E_XDP_XMIT_MODE_FRAME });
111 		mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
112 				     (union mlx5e_xdp_info) { .frame.xdpf = xdpf });
113 		mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
114 				     (union mlx5e_xdp_info) { .frame.dma_addr = dma_addr });
115 		return true;
116 	}
117 
118 	/* Driver assumes that xdp_convert_buff_to_frame returns an xdp_frame
119 	 * that points to the same memory region as the original xdp_buff. It
120 	 * allows to map the memory only once and to use the DMA_BIDIRECTIONAL
121 	 * mode.
122 	 */
123 
124 	dma_addr = page_pool_get_dma_addr(page) + (xdpf->data - (void *)xdpf);
125 	dma_sync_single_for_device(sq->pdev, dma_addr, xdptxd->len, DMA_BIDIRECTIONAL);
126 
127 	if (xdptxd->has_frags) {
128 		xdptxdf.sinfo = xdp_get_shared_info_from_frame(xdpf);
129 		xdptxdf.dma_arr = NULL;
130 
131 		for (i = 0; i < xdptxdf.sinfo->nr_frags; i++) {
132 			skb_frag_t *frag = &xdptxdf.sinfo->frags[i];
133 			dma_addr_t addr;
134 			u32 len;
135 
136 			addr = page_pool_get_dma_addr(skb_frag_page(frag)) +
137 				skb_frag_off(frag);
138 			len = skb_frag_size(frag);
139 			dma_sync_single_for_device(sq->pdev, addr, len,
140 						   DMA_BIDIRECTIONAL);
141 		}
142 	}
143 
144 	xdptxd->dma_addr = dma_addr;
145 
146 	if (unlikely(!INDIRECT_CALL_2(sq->xmit_xdp_frame, mlx5e_xmit_xdp_frame_mpwqe,
147 				      mlx5e_xmit_xdp_frame, sq, xdptxd, 0)))
148 		return false;
149 
150 	/* xmit_mode == MLX5E_XDP_XMIT_MODE_PAGE */
151 	mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
152 			     (union mlx5e_xdp_info) { .mode = MLX5E_XDP_XMIT_MODE_PAGE });
153 
154 	if (xdptxd->has_frags) {
155 		mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
156 				     (union mlx5e_xdp_info)
157 				     { .page.num = 1 + xdptxdf.sinfo->nr_frags });
158 		mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
159 				     (union mlx5e_xdp_info) { .page.page = page });
160 		for (i = 0; i < xdptxdf.sinfo->nr_frags; i++) {
161 			skb_frag_t *frag = &xdptxdf.sinfo->frags[i];
162 
163 			mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
164 					     (union mlx5e_xdp_info)
165 					     { .page.page = skb_frag_page(frag) });
166 		}
167 	} else {
168 		mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
169 				     (union mlx5e_xdp_info) { .page.num = 1 });
170 		mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
171 				     (union mlx5e_xdp_info) { .page.page = page });
172 	}
173 
174 	return true;
175 }
176 
177 static int mlx5e_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp)
178 {
179 	const struct mlx5e_xdp_buff *_ctx = (void *)ctx;
180 
181 	if (unlikely(!mlx5e_rx_hw_stamp(_ctx->rq->tstamp)))
182 		return -ENODATA;
183 
184 	*timestamp =  mlx5e_cqe_ts_to_ns(_ctx->rq->ptp_cyc2time,
185 					 _ctx->rq->clock, get_cqe_ts(_ctx->cqe));
186 	return 0;
187 }
188 
189 /* Mapping HW RSS Type bits CQE_RSS_HTYPE_IP + CQE_RSS_HTYPE_L4 into 4-bits*/
190 #define RSS_TYPE_MAX_TABLE	16 /* 4-bits max 16 entries */
191 #define RSS_L4		GENMASK(1, 0)
192 #define RSS_L3		GENMASK(3, 2) /* Same as CQE_RSS_HTYPE_IP */
193 
194 /* Valid combinations of CQE_RSS_HTYPE_IP + CQE_RSS_HTYPE_L4 sorted numerical */
195 enum mlx5_rss_hash_type {
196 	RSS_TYPE_NO_HASH	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IP_NONE) |
197 				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
198 	RSS_TYPE_L3_IPV4	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
199 				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
200 	RSS_TYPE_L4_IPV4_TCP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
201 				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_TCP)),
202 	RSS_TYPE_L4_IPV4_UDP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
203 				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_UDP)),
204 	RSS_TYPE_L4_IPV4_IPSEC	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
205 				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_IPSEC)),
206 	RSS_TYPE_L3_IPV6	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
207 				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
208 	RSS_TYPE_L4_IPV6_TCP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
209 				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_TCP)),
210 	RSS_TYPE_L4_IPV6_UDP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
211 				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_UDP)),
212 	RSS_TYPE_L4_IPV6_IPSEC	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
213 				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_IPSEC)),
214 };
215 
216 /* Invalid combinations will simply return zero, allows no boundary checks */
217 static const enum xdp_rss_hash_type mlx5_xdp_rss_type[RSS_TYPE_MAX_TABLE] = {
218 	[RSS_TYPE_NO_HASH]	 = XDP_RSS_TYPE_NONE,
219 	[1]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
220 	[2]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
221 	[3]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
222 	[RSS_TYPE_L3_IPV4]	 = XDP_RSS_TYPE_L3_IPV4,
223 	[RSS_TYPE_L4_IPV4_TCP]	 = XDP_RSS_TYPE_L4_IPV4_TCP,
224 	[RSS_TYPE_L4_IPV4_UDP]	 = XDP_RSS_TYPE_L4_IPV4_UDP,
225 	[RSS_TYPE_L4_IPV4_IPSEC] = XDP_RSS_TYPE_L4_IPV4_IPSEC,
226 	[RSS_TYPE_L3_IPV6]	 = XDP_RSS_TYPE_L3_IPV6,
227 	[RSS_TYPE_L4_IPV6_TCP]	 = XDP_RSS_TYPE_L4_IPV6_TCP,
228 	[RSS_TYPE_L4_IPV6_UDP]   = XDP_RSS_TYPE_L4_IPV6_UDP,
229 	[RSS_TYPE_L4_IPV6_IPSEC] = XDP_RSS_TYPE_L4_IPV6_IPSEC,
230 	[12]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
231 	[13]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
232 	[14]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
233 	[15]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
234 };
235 
236 static int mlx5e_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
237 			     enum xdp_rss_hash_type *rss_type)
238 {
239 	const struct mlx5e_xdp_buff *_ctx = (void *)ctx;
240 	const struct mlx5_cqe64 *cqe = _ctx->cqe;
241 	u32 hash_type, l4_type, ip_type, lookup;
242 
243 	if (unlikely(!(_ctx->xdp.rxq->dev->features & NETIF_F_RXHASH)))
244 		return -ENODATA;
245 
246 	*hash = be32_to_cpu(cqe->rss_hash_result);
247 
248 	hash_type = cqe->rss_hash_type;
249 	BUILD_BUG_ON(CQE_RSS_HTYPE_IP != RSS_L3); /* same mask */
250 	ip_type = hash_type & CQE_RSS_HTYPE_IP;
251 	l4_type = FIELD_GET(CQE_RSS_HTYPE_L4, hash_type);
252 	lookup = ip_type | l4_type;
253 	*rss_type = mlx5_xdp_rss_type[lookup];
254 
255 	return 0;
256 }
257 
258 const struct xdp_metadata_ops mlx5e_xdp_metadata_ops = {
259 	.xmo_rx_timestamp		= mlx5e_xdp_rx_timestamp,
260 	.xmo_rx_hash			= mlx5e_xdp_rx_hash,
261 };
262 
263 /* returns true if packet was consumed by xdp */
264 bool mlx5e_xdp_handle(struct mlx5e_rq *rq,
265 		      struct bpf_prog *prog, struct mlx5e_xdp_buff *mxbuf)
266 {
267 	struct xdp_buff *xdp = &mxbuf->xdp;
268 	u32 act;
269 	int err;
270 
271 	act = bpf_prog_run_xdp(prog, xdp);
272 	switch (act) {
273 	case XDP_PASS:
274 		return false;
275 	case XDP_TX:
276 		if (unlikely(!mlx5e_xmit_xdp_buff(rq->xdpsq, rq, xdp)))
277 			goto xdp_abort;
278 		__set_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags); /* non-atomic */
279 		return true;
280 	case XDP_REDIRECT:
281 		/* When XDP enabled then page-refcnt==1 here */
282 		err = xdp_do_redirect(rq->netdev, xdp, prog);
283 		if (unlikely(err))
284 			goto xdp_abort;
285 		__set_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags);
286 		__set_bit(MLX5E_RQ_FLAG_XDP_REDIRECT, rq->flags);
287 		rq->stats->xdp_redirect++;
288 		return true;
289 	default:
290 		bpf_warn_invalid_xdp_action(rq->netdev, prog, act);
291 		fallthrough;
292 	case XDP_ABORTED:
293 xdp_abort:
294 		trace_xdp_exception(rq->netdev, prog, act);
295 		fallthrough;
296 	case XDP_DROP:
297 		rq->stats->xdp_drop++;
298 		return true;
299 	}
300 }
301 
302 static u16 mlx5e_xdpsq_get_next_pi(struct mlx5e_xdpsq *sq, u16 size)
303 {
304 	struct mlx5_wq_cyc *wq = &sq->wq;
305 	u16 pi, contig_wqebbs;
306 
307 	pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);
308 	contig_wqebbs = mlx5_wq_cyc_get_contig_wqebbs(wq, pi);
309 	if (unlikely(contig_wqebbs < size)) {
310 		struct mlx5e_xdp_wqe_info *wi, *edge_wi;
311 
312 		wi = &sq->db.wqe_info[pi];
313 		edge_wi = wi + contig_wqebbs;
314 
315 		/* Fill SQ frag edge with NOPs to avoid WQE wrapping two pages. */
316 		for (; wi < edge_wi; wi++) {
317 			*wi = (struct mlx5e_xdp_wqe_info) {
318 				.num_wqebbs = 1,
319 				.num_pkts = 0,
320 			};
321 			mlx5e_post_nop(wq, sq->sqn, &sq->pc);
322 		}
323 		sq->stats->nops += contig_wqebbs;
324 
325 		pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);
326 	}
327 
328 	return pi;
329 }
330 
331 static void mlx5e_xdp_mpwqe_session_start(struct mlx5e_xdpsq *sq)
332 {
333 	struct mlx5e_tx_mpwqe *session = &sq->mpwqe;
334 	struct mlx5e_xdpsq_stats *stats = sq->stats;
335 	struct mlx5e_tx_wqe *wqe;
336 	u16 pi;
337 
338 	pi = mlx5e_xdpsq_get_next_pi(sq, sq->max_sq_mpw_wqebbs);
339 	wqe = MLX5E_TX_FETCH_WQE(sq, pi);
340 	net_prefetchw(wqe->data);
341 
342 	*session = (struct mlx5e_tx_mpwqe) {
343 		.wqe = wqe,
344 		.bytes_count = 0,
345 		.ds_count = MLX5E_TX_WQE_EMPTY_DS_COUNT,
346 		.pkt_count = 0,
347 		.inline_on = mlx5e_xdp_get_inline_state(sq, session->inline_on),
348 	};
349 
350 	stats->mpwqe++;
351 }
352 
353 void mlx5e_xdp_mpwqe_complete(struct mlx5e_xdpsq *sq)
354 {
355 	struct mlx5_wq_cyc       *wq    = &sq->wq;
356 	struct mlx5e_tx_mpwqe *session = &sq->mpwqe;
357 	struct mlx5_wqe_ctrl_seg *cseg = &session->wqe->ctrl;
358 	u16 ds_count = session->ds_count;
359 	u16 pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);
360 	struct mlx5e_xdp_wqe_info *wi = &sq->db.wqe_info[pi];
361 
362 	cseg->opmod_idx_opcode =
363 		cpu_to_be32((sq->pc << 8) | MLX5_OPCODE_ENHANCED_MPSW);
364 	cseg->qpn_ds = cpu_to_be32((sq->sqn << 8) | ds_count);
365 
366 	wi->num_wqebbs = DIV_ROUND_UP(ds_count, MLX5_SEND_WQEBB_NUM_DS);
367 	wi->num_pkts   = session->pkt_count;
368 
369 	sq->pc += wi->num_wqebbs;
370 
371 	sq->doorbell_cseg = cseg;
372 
373 	session->wqe = NULL; /* Close session */
374 }
375 
376 enum {
377 	MLX5E_XDP_CHECK_OK = 1,
378 	MLX5E_XDP_CHECK_START_MPWQE = 2,
379 };
380 
381 INDIRECT_CALLABLE_SCOPE int mlx5e_xmit_xdp_frame_check_mpwqe(struct mlx5e_xdpsq *sq)
382 {
383 	if (unlikely(!sq->mpwqe.wqe)) {
384 		if (unlikely(!mlx5e_wqc_has_room_for(&sq->wq, sq->cc, sq->pc,
385 						     sq->stop_room))) {
386 			/* SQ is full, ring doorbell */
387 			mlx5e_xmit_xdp_doorbell(sq);
388 			sq->stats->full++;
389 			return -EBUSY;
390 		}
391 
392 		return MLX5E_XDP_CHECK_START_MPWQE;
393 	}
394 
395 	return MLX5E_XDP_CHECK_OK;
396 }
397 
398 INDIRECT_CALLABLE_SCOPE bool
399 mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd,
400 		     int check_result);
401 
402 INDIRECT_CALLABLE_SCOPE bool
403 mlx5e_xmit_xdp_frame_mpwqe(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd,
404 			   int check_result)
405 {
406 	struct mlx5e_tx_mpwqe *session = &sq->mpwqe;
407 	struct mlx5e_xdpsq_stats *stats = sq->stats;
408 
409 	if (xdptxd->has_frags) {
410 		/* MPWQE is enabled, but a multi-buffer packet is queued for
411 		 * transmission. MPWQE can't send fragmented packets, so close
412 		 * the current session and fall back to a regular WQE.
413 		 */
414 		if (unlikely(sq->mpwqe.wqe))
415 			mlx5e_xdp_mpwqe_complete(sq);
416 		return mlx5e_xmit_xdp_frame(sq, xdptxd, 0);
417 	}
418 
419 	if (unlikely(xdptxd->len > sq->hw_mtu)) {
420 		stats->err++;
421 		return false;
422 	}
423 
424 	if (!check_result)
425 		check_result = mlx5e_xmit_xdp_frame_check_mpwqe(sq);
426 	if (unlikely(check_result < 0))
427 		return false;
428 
429 	if (check_result == MLX5E_XDP_CHECK_START_MPWQE) {
430 		/* Start the session when nothing can fail, so it's guaranteed
431 		 * that if there is an active session, it has at least one dseg,
432 		 * and it's safe to complete it at any time.
433 		 */
434 		mlx5e_xdp_mpwqe_session_start(sq);
435 	}
436 
437 	mlx5e_xdp_mpwqe_add_dseg(sq, xdptxd, stats);
438 
439 	if (unlikely(mlx5e_xdp_mpwqe_is_full(session, sq->max_sq_mpw_wqebbs)))
440 		mlx5e_xdp_mpwqe_complete(sq);
441 
442 	stats->xmit++;
443 	return true;
444 }
445 
446 static int mlx5e_xmit_xdp_frame_check_stop_room(struct mlx5e_xdpsq *sq, int stop_room)
447 {
448 	if (unlikely(!mlx5e_wqc_has_room_for(&sq->wq, sq->cc, sq->pc, stop_room))) {
449 		/* SQ is full, ring doorbell */
450 		mlx5e_xmit_xdp_doorbell(sq);
451 		sq->stats->full++;
452 		return -EBUSY;
453 	}
454 
455 	return MLX5E_XDP_CHECK_OK;
456 }
457 
458 INDIRECT_CALLABLE_SCOPE int mlx5e_xmit_xdp_frame_check(struct mlx5e_xdpsq *sq)
459 {
460 	return mlx5e_xmit_xdp_frame_check_stop_room(sq, 1);
461 }
462 
463 INDIRECT_CALLABLE_SCOPE bool
464 mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq, struct mlx5e_xmit_data *xdptxd,
465 		     int check_result)
466 {
467 	struct mlx5e_xmit_data_frags *xdptxdf =
468 		container_of(xdptxd, struct mlx5e_xmit_data_frags, xd);
469 	struct mlx5_wq_cyc       *wq   = &sq->wq;
470 	struct mlx5_wqe_ctrl_seg *cseg;
471 	struct mlx5_wqe_data_seg *dseg;
472 	struct mlx5_wqe_eth_seg *eseg;
473 	struct mlx5e_tx_wqe *wqe;
474 
475 	dma_addr_t dma_addr = xdptxd->dma_addr;
476 	u32 dma_len = xdptxd->len;
477 	u16 ds_cnt, inline_hdr_sz;
478 	u8 num_wqebbs = 1;
479 	int num_frags = 0;
480 	u16 pi;
481 
482 	struct mlx5e_xdpsq_stats *stats = sq->stats;
483 
484 	if (unlikely(dma_len < MLX5E_XDP_MIN_INLINE || sq->hw_mtu < dma_len)) {
485 		stats->err++;
486 		return false;
487 	}
488 
489 	ds_cnt = MLX5E_TX_WQE_EMPTY_DS_COUNT + 1;
490 	if (sq->min_inline_mode != MLX5_INLINE_MODE_NONE)
491 		ds_cnt++;
492 
493 	/* check_result must be 0 if sinfo is passed. */
494 	if (!check_result) {
495 		int stop_room = 1;
496 
497 		if (xdptxd->has_frags) {
498 			ds_cnt += xdptxdf->sinfo->nr_frags;
499 			num_frags = xdptxdf->sinfo->nr_frags;
500 			num_wqebbs = DIV_ROUND_UP(ds_cnt, MLX5_SEND_WQEBB_NUM_DS);
501 			/* Assuming MLX5_CAP_GEN(mdev, max_wqe_sz_sq) is big
502 			 * enough to hold all fragments.
503 			 */
504 			stop_room = MLX5E_STOP_ROOM(num_wqebbs);
505 		}
506 
507 		check_result = mlx5e_xmit_xdp_frame_check_stop_room(sq, stop_room);
508 	}
509 	if (unlikely(check_result < 0))
510 		return false;
511 
512 	pi = mlx5e_xdpsq_get_next_pi(sq, num_wqebbs);
513 	wqe = mlx5_wq_cyc_get_wqe(wq, pi);
514 	net_prefetchw(wqe);
515 
516 	cseg = &wqe->ctrl;
517 	eseg = &wqe->eth;
518 	dseg = wqe->data;
519 
520 	inline_hdr_sz = 0;
521 
522 	/* copy the inline part if required */
523 	if (sq->min_inline_mode != MLX5_INLINE_MODE_NONE) {
524 		memcpy(eseg->inline_hdr.start, xdptxd->data, sizeof(eseg->inline_hdr.start));
525 		memcpy(dseg, xdptxd->data + sizeof(eseg->inline_hdr.start),
526 		       MLX5E_XDP_MIN_INLINE - sizeof(eseg->inline_hdr.start));
527 		dma_len  -= MLX5E_XDP_MIN_INLINE;
528 		dma_addr += MLX5E_XDP_MIN_INLINE;
529 		inline_hdr_sz = MLX5E_XDP_MIN_INLINE;
530 		dseg++;
531 	}
532 
533 	/* write the dma part */
534 	dseg->addr       = cpu_to_be64(dma_addr);
535 	dseg->byte_count = cpu_to_be32(dma_len);
536 
537 	cseg->opmod_idx_opcode = cpu_to_be32((sq->pc << 8) | MLX5_OPCODE_SEND);
538 
539 	if (test_bit(MLX5E_SQ_STATE_XDP_MULTIBUF, &sq->state)) {
540 		int i;
541 
542 		memset(&cseg->trailer, 0, sizeof(cseg->trailer));
543 		memset(eseg, 0, sizeof(*eseg) - sizeof(eseg->trailer));
544 
545 		eseg->inline_hdr.sz = cpu_to_be16(inline_hdr_sz);
546 		dseg->lkey = sq->mkey_be;
547 
548 		for (i = 0; i < num_frags; i++) {
549 			skb_frag_t *frag = &xdptxdf->sinfo->frags[i];
550 			dma_addr_t addr;
551 
552 			addr = xdptxdf->dma_arr ? xdptxdf->dma_arr[i] :
553 				page_pool_get_dma_addr(skb_frag_page(frag)) +
554 				skb_frag_off(frag);
555 
556 			dseg++;
557 			dseg->addr = cpu_to_be64(addr);
558 			dseg->byte_count = cpu_to_be32(skb_frag_size(frag));
559 			dseg->lkey = sq->mkey_be;
560 		}
561 
562 		cseg->qpn_ds = cpu_to_be32((sq->sqn << 8) | ds_cnt);
563 
564 		sq->db.wqe_info[pi] = (struct mlx5e_xdp_wqe_info) {
565 			.num_wqebbs = num_wqebbs,
566 			.num_pkts = 1,
567 		};
568 
569 		sq->pc += num_wqebbs;
570 	} else {
571 		cseg->fm_ce_se = 0;
572 
573 		sq->pc++;
574 	}
575 
576 	sq->doorbell_cseg = cseg;
577 
578 	stats->xmit++;
579 	return true;
580 }
581 
582 static void mlx5e_free_xdpsq_desc(struct mlx5e_xdpsq *sq,
583 				  struct mlx5e_xdp_wqe_info *wi,
584 				  u32 *xsk_frames,
585 				  struct xdp_frame_bulk *bq)
586 {
587 	struct mlx5e_xdp_info_fifo *xdpi_fifo = &sq->db.xdpi_fifo;
588 	u16 i;
589 
590 	for (i = 0; i < wi->num_pkts; i++) {
591 		union mlx5e_xdp_info xdpi = mlx5e_xdpi_fifo_pop(xdpi_fifo);
592 
593 		switch (xdpi.mode) {
594 		case MLX5E_XDP_XMIT_MODE_FRAME: {
595 			/* XDP_TX from the XSK RQ and XDP_REDIRECT */
596 			struct xdp_frame *xdpf;
597 			dma_addr_t dma_addr;
598 
599 			xdpi = mlx5e_xdpi_fifo_pop(xdpi_fifo);
600 			xdpf = xdpi.frame.xdpf;
601 			xdpi = mlx5e_xdpi_fifo_pop(xdpi_fifo);
602 			dma_addr = xdpi.frame.dma_addr;
603 
604 			dma_unmap_single(sq->pdev, dma_addr,
605 					 xdpf->len, DMA_TO_DEVICE);
606 			if (xdp_frame_has_frags(xdpf)) {
607 				struct skb_shared_info *sinfo;
608 				int j;
609 
610 				sinfo = xdp_get_shared_info_from_frame(xdpf);
611 				for (j = 0; j < sinfo->nr_frags; j++) {
612 					skb_frag_t *frag = &sinfo->frags[j];
613 
614 					xdpi = mlx5e_xdpi_fifo_pop(xdpi_fifo);
615 					dma_addr = xdpi.frame.dma_addr;
616 
617 					dma_unmap_single(sq->pdev, dma_addr,
618 							 skb_frag_size(frag), DMA_TO_DEVICE);
619 				}
620 			}
621 			xdp_return_frame_bulk(xdpf, bq);
622 			break;
623 		}
624 		case MLX5E_XDP_XMIT_MODE_PAGE: {
625 			/* XDP_TX from the regular RQ */
626 			u8 num, n = 0;
627 
628 			xdpi = mlx5e_xdpi_fifo_pop(xdpi_fifo);
629 			num = xdpi.page.num;
630 
631 			do {
632 				struct page *page;
633 
634 				xdpi = mlx5e_xdpi_fifo_pop(xdpi_fifo);
635 				page = xdpi.page.page;
636 
637 				/* No need to check ((page->pp_magic & ~0x3UL) == PP_SIGNATURE)
638 				 * as we know this is a page_pool page.
639 				 */
640 				page_pool_put_defragged_page(page->pp,
641 							     page, -1, true);
642 			} while (++n < num);
643 
644 			break;
645 		}
646 		case MLX5E_XDP_XMIT_MODE_XSK:
647 			/* AF_XDP send */
648 			(*xsk_frames)++;
649 			break;
650 		default:
651 			WARN_ON_ONCE(true);
652 		}
653 	}
654 }
655 
656 bool mlx5e_poll_xdpsq_cq(struct mlx5e_cq *cq)
657 {
658 	struct xdp_frame_bulk bq;
659 	struct mlx5e_xdpsq *sq;
660 	struct mlx5_cqe64 *cqe;
661 	u32 xsk_frames = 0;
662 	u16 sqcc;
663 	int i;
664 
665 	xdp_frame_bulk_init(&bq);
666 
667 	sq = container_of(cq, struct mlx5e_xdpsq, cq);
668 
669 	if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &sq->state)))
670 		return false;
671 
672 	cqe = mlx5_cqwq_get_cqe(&cq->wq);
673 	if (!cqe)
674 		return false;
675 
676 	/* sq->cc must be updated only after mlx5_cqwq_update_db_record(),
677 	 * otherwise a cq overrun may occur
678 	 */
679 	sqcc = sq->cc;
680 
681 	i = 0;
682 	do {
683 		struct mlx5e_xdp_wqe_info *wi;
684 		u16 wqe_counter, ci;
685 		bool last_wqe;
686 
687 		mlx5_cqwq_pop(&cq->wq);
688 
689 		wqe_counter = be16_to_cpu(cqe->wqe_counter);
690 
691 		do {
692 			last_wqe = (sqcc == wqe_counter);
693 			ci = mlx5_wq_cyc_ctr2ix(&sq->wq, sqcc);
694 			wi = &sq->db.wqe_info[ci];
695 
696 			sqcc += wi->num_wqebbs;
697 
698 			mlx5e_free_xdpsq_desc(sq, wi, &xsk_frames, &bq);
699 		} while (!last_wqe);
700 
701 		if (unlikely(get_cqe_opcode(cqe) != MLX5_CQE_REQ)) {
702 			netdev_WARN_ONCE(sq->channel->netdev,
703 					 "Bad OP in XDPSQ CQE: 0x%x\n",
704 					 get_cqe_opcode(cqe));
705 			mlx5e_dump_error_cqe(&sq->cq, sq->sqn,
706 					     (struct mlx5_err_cqe *)cqe);
707 			mlx5_wq_cyc_wqe_dump(&sq->wq, ci, wi->num_wqebbs);
708 		}
709 	} while ((++i < MLX5E_TX_CQ_POLL_BUDGET) && (cqe = mlx5_cqwq_get_cqe(&cq->wq)));
710 
711 	xdp_flush_frame_bulk(&bq);
712 
713 	if (xsk_frames)
714 		xsk_tx_completed(sq->xsk_pool, xsk_frames);
715 
716 	sq->stats->cqes += i;
717 
718 	mlx5_cqwq_update_db_record(&cq->wq);
719 
720 	/* ensure cq space is freed before enabling more cqes */
721 	wmb();
722 
723 	sq->cc = sqcc;
724 	return (i == MLX5E_TX_CQ_POLL_BUDGET);
725 }
726 
727 void mlx5e_free_xdpsq_descs(struct mlx5e_xdpsq *sq)
728 {
729 	struct xdp_frame_bulk bq;
730 	u32 xsk_frames = 0;
731 
732 	xdp_frame_bulk_init(&bq);
733 
734 	rcu_read_lock(); /* need for xdp_return_frame_bulk */
735 
736 	while (sq->cc != sq->pc) {
737 		struct mlx5e_xdp_wqe_info *wi;
738 		u16 ci;
739 
740 		ci = mlx5_wq_cyc_ctr2ix(&sq->wq, sq->cc);
741 		wi = &sq->db.wqe_info[ci];
742 
743 		sq->cc += wi->num_wqebbs;
744 
745 		mlx5e_free_xdpsq_desc(sq, wi, &xsk_frames, &bq);
746 	}
747 
748 	xdp_flush_frame_bulk(&bq);
749 	rcu_read_unlock();
750 
751 	if (xsk_frames)
752 		xsk_tx_completed(sq->xsk_pool, xsk_frames);
753 }
754 
755 int mlx5e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
756 		   u32 flags)
757 {
758 	struct mlx5e_priv *priv = netdev_priv(dev);
759 	struct mlx5e_xdpsq *sq;
760 	int nxmit = 0;
761 	int sq_num;
762 	int i;
763 
764 	/* this flag is sufficient, no need to test internal sq state */
765 	if (unlikely(!mlx5e_xdp_tx_is_enabled(priv)))
766 		return -ENETDOWN;
767 
768 	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
769 		return -EINVAL;
770 
771 	sq_num = smp_processor_id();
772 
773 	if (unlikely(sq_num >= priv->channels.num))
774 		return -ENXIO;
775 
776 	sq = &priv->channels.c[sq_num]->xdpsq;
777 
778 	for (i = 0; i < n; i++) {
779 		struct mlx5e_xmit_data_frags xdptxdf = {};
780 		struct xdp_frame *xdpf = frames[i];
781 		dma_addr_t dma_arr[MAX_SKB_FRAGS];
782 		struct mlx5e_xmit_data *xdptxd;
783 		bool ret;
784 
785 		xdptxd = &xdptxdf.xd;
786 		xdptxd->data = xdpf->data;
787 		xdptxd->len = xdpf->len;
788 		xdptxd->has_frags = xdp_frame_has_frags(xdpf);
789 		xdptxd->dma_addr = dma_map_single(sq->pdev, xdptxd->data,
790 						  xdptxd->len, DMA_TO_DEVICE);
791 
792 		if (unlikely(dma_mapping_error(sq->pdev, xdptxd->dma_addr)))
793 			break;
794 
795 		if (xdptxd->has_frags) {
796 			int j;
797 
798 			xdptxdf.sinfo = xdp_get_shared_info_from_frame(xdpf);
799 			xdptxdf.dma_arr = dma_arr;
800 			for (j = 0; j < xdptxdf.sinfo->nr_frags; j++) {
801 				skb_frag_t *frag = &xdptxdf.sinfo->frags[j];
802 
803 				dma_arr[j] = dma_map_single(sq->pdev, skb_frag_address(frag),
804 							    skb_frag_size(frag), DMA_TO_DEVICE);
805 
806 				if (!dma_mapping_error(sq->pdev, dma_arr[j]))
807 					continue;
808 				/* mapping error */
809 				while (--j >= 0)
810 					dma_unmap_single(sq->pdev, dma_arr[j],
811 							 skb_frag_size(&xdptxdf.sinfo->frags[j]),
812 							 DMA_TO_DEVICE);
813 				goto out;
814 			}
815 		}
816 
817 		ret = INDIRECT_CALL_2(sq->xmit_xdp_frame, mlx5e_xmit_xdp_frame_mpwqe,
818 				      mlx5e_xmit_xdp_frame, sq, xdptxd, 0);
819 		if (unlikely(!ret)) {
820 			int j;
821 
822 			dma_unmap_single(sq->pdev, xdptxd->dma_addr,
823 					 xdptxd->len, DMA_TO_DEVICE);
824 			if (!xdptxd->has_frags)
825 				break;
826 			for (j = 0; j < xdptxdf.sinfo->nr_frags; j++)
827 				dma_unmap_single(sq->pdev, dma_arr[j],
828 						 skb_frag_size(&xdptxdf.sinfo->frags[j]),
829 						 DMA_TO_DEVICE);
830 			break;
831 		}
832 
833 		/* xmit_mode == MLX5E_XDP_XMIT_MODE_FRAME */
834 		mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
835 				     (union mlx5e_xdp_info) { .mode = MLX5E_XDP_XMIT_MODE_FRAME });
836 		mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
837 				     (union mlx5e_xdp_info) { .frame.xdpf = xdpf });
838 		mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
839 				     (union mlx5e_xdp_info) { .frame.dma_addr = xdptxd->dma_addr });
840 		if (xdptxd->has_frags) {
841 			int j;
842 
843 			for (j = 0; j < xdptxdf.sinfo->nr_frags; j++)
844 				mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo,
845 						     (union mlx5e_xdp_info)
846 						     { .frame.dma_addr = dma_arr[j] });
847 		}
848 		nxmit++;
849 	}
850 
851 out:
852 	if (flags & XDP_XMIT_FLUSH) {
853 		if (sq->mpwqe.wqe)
854 			mlx5e_xdp_mpwqe_complete(sq);
855 		mlx5e_xmit_xdp_doorbell(sq);
856 	}
857 
858 	return nxmit;
859 }
860 
861 void mlx5e_xdp_rx_poll_complete(struct mlx5e_rq *rq)
862 {
863 	struct mlx5e_xdpsq *xdpsq = rq->xdpsq;
864 
865 	if (xdpsq->mpwqe.wqe)
866 		mlx5e_xdp_mpwqe_complete(xdpsq);
867 
868 	mlx5e_xmit_xdp_doorbell(xdpsq);
869 
870 	if (test_bit(MLX5E_RQ_FLAG_XDP_REDIRECT, rq->flags)) {
871 		xdp_do_flush_map();
872 		__clear_bit(MLX5E_RQ_FLAG_XDP_REDIRECT, rq->flags);
873 	}
874 }
875 
876 void mlx5e_set_xmit_fp(struct mlx5e_xdpsq *sq, bool is_mpw)
877 {
878 	sq->xmit_xdp_frame_check = is_mpw ?
879 		mlx5e_xmit_xdp_frame_check_mpwqe : mlx5e_xmit_xdp_frame_check;
880 	sq->xmit_xdp_frame = is_mpw ?
881 		mlx5e_xmit_xdp_frame_mpwqe : mlx5e_xmit_xdp_frame;
882 }
883