xref: /linux/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.h (revision 06d07429858317ded2db7986113a9e0129cd599b)
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 #ifndef __MLX5_EN_XDP_H__
33 #define __MLX5_EN_XDP_H__
34 
35 #include <linux/indirect_call_wrapper.h>
36 #include <net/xdp_sock.h>
37 
38 #include "en.h"
39 #include "en/txrx.h"
40 
41 #define MLX5E_XDP_MIN_INLINE (ETH_HLEN + VLAN_HLEN)
42 
43 #define MLX5E_XDP_INLINE_WQE_MAX_DS_CNT 16
44 #define MLX5E_XDP_INLINE_WQE_SZ_THRSD \
45 	(MLX5E_XDP_INLINE_WQE_MAX_DS_CNT * MLX5_SEND_WQE_DS - \
46 	 sizeof(struct mlx5_wqe_inline_seg))
47 
48 struct mlx5e_xdp_buff {
49 	struct xdp_buff xdp;
50 	struct mlx5_cqe64 *cqe;
51 	struct mlx5e_rq *rq;
52 };
53 
54 /* XDP packets can be transmitted in different ways. On completion, we need to
55  * distinguish between them to clean up things in a proper way.
56  */
57 enum mlx5e_xdp_xmit_mode {
58 	/* An xdp_frame was transmitted due to either XDP_REDIRECT from another
59 	 * device or XDP_TX from an XSK RQ. The frame has to be unmapped and
60 	 * returned.
61 	 */
62 	MLX5E_XDP_XMIT_MODE_FRAME,
63 
64 	/* The xdp_frame was created in place as a result of XDP_TX from a
65 	 * regular RQ. No DMA remapping happened, and the page belongs to us.
66 	 */
67 	MLX5E_XDP_XMIT_MODE_PAGE,
68 
69 	/* No xdp_frame was created at all, the transmit happened from a UMEM
70 	 * page. The UMEM Completion Ring producer pointer has to be increased.
71 	 */
72 	MLX5E_XDP_XMIT_MODE_XSK,
73 };
74 
75 /* xmit_mode entry is pushed to the fifo per packet, followed by multiple
76  * entries, as follows:
77  *
78  * MLX5E_XDP_XMIT_MODE_FRAME:
79  *    xdpf, dma_addr_1, dma_addr_2, ... , dma_addr_num.
80  *    'num' is derived from xdpf.
81  *
82  * MLX5E_XDP_XMIT_MODE_PAGE:
83  *    num, page_1, page_2, ... , page_num.
84  *
85  * MLX5E_XDP_XMIT_MODE_XSK:
86  *    frame.xsk_meta.
87  */
88 #define MLX5E_XDP_FIFO_ENTRIES2DS_MAX_RATIO 4
89 
90 union mlx5e_xdp_info {
91 	enum mlx5e_xdp_xmit_mode mode;
92 	union {
93 		struct xdp_frame *xdpf;
94 		dma_addr_t dma_addr;
95 	} frame;
96 	union {
97 		struct mlx5e_rq *rq;
98 		u8 num;
99 		struct page *page;
100 	} page;
101 	struct xsk_tx_metadata_compl xsk_meta;
102 };
103 
104 struct mlx5e_xsk_param;
105 int mlx5e_xdp_max_mtu(struct mlx5e_params *params, struct mlx5e_xsk_param *xsk);
106 bool mlx5e_xdp_handle(struct mlx5e_rq *rq,
107 		      struct bpf_prog *prog, struct mlx5e_xdp_buff *mlctx);
108 void mlx5e_xdp_mpwqe_complete(struct mlx5e_xdpsq *sq);
109 bool mlx5e_poll_xdpsq_cq(struct mlx5e_cq *cq);
110 void mlx5e_free_xdpsq_descs(struct mlx5e_xdpsq *sq);
111 void mlx5e_set_xmit_fp(struct mlx5e_xdpsq *sq, bool is_mpw);
112 void mlx5e_xdp_rx_poll_complete(struct mlx5e_rq *rq);
113 int mlx5e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
114 		   u32 flags);
115 
116 extern const struct xdp_metadata_ops mlx5e_xdp_metadata_ops;
117 extern const struct xsk_tx_metadata_ops mlx5e_xsk_tx_metadata_ops;
118 
119 INDIRECT_CALLABLE_DECLARE(bool mlx5e_xmit_xdp_frame_mpwqe(struct mlx5e_xdpsq *sq,
120 							  struct mlx5e_xmit_data *xdptxd,
121 							  int check_result,
122 							  struct xsk_tx_metadata *meta));
123 INDIRECT_CALLABLE_DECLARE(bool mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq,
124 						    struct mlx5e_xmit_data *xdptxd,
125 						    int check_result,
126 						    struct xsk_tx_metadata *meta));
127 INDIRECT_CALLABLE_DECLARE(int mlx5e_xmit_xdp_frame_check_mpwqe(struct mlx5e_xdpsq *sq));
128 INDIRECT_CALLABLE_DECLARE(int mlx5e_xmit_xdp_frame_check(struct mlx5e_xdpsq *sq));
129 
mlx5e_xdp_tx_enable(struct mlx5e_priv * priv)130 static inline void mlx5e_xdp_tx_enable(struct mlx5e_priv *priv)
131 {
132 	set_bit(MLX5E_STATE_XDP_TX_ENABLED, &priv->state);
133 
134 	if (priv->channels.params.xdp_prog)
135 		set_bit(MLX5E_STATE_XDP_ACTIVE, &priv->state);
136 }
137 
mlx5e_xdp_tx_disable(struct mlx5e_priv * priv)138 static inline void mlx5e_xdp_tx_disable(struct mlx5e_priv *priv)
139 {
140 	if (priv->channels.params.xdp_prog)
141 		clear_bit(MLX5E_STATE_XDP_ACTIVE, &priv->state);
142 
143 	clear_bit(MLX5E_STATE_XDP_TX_ENABLED, &priv->state);
144 	/* Let other device's napi(s) and XSK wakeups see our new state. */
145 	synchronize_net();
146 }
147 
mlx5e_xdp_tx_is_enabled(struct mlx5e_priv * priv)148 static inline bool mlx5e_xdp_tx_is_enabled(struct mlx5e_priv *priv)
149 {
150 	return test_bit(MLX5E_STATE_XDP_TX_ENABLED, &priv->state);
151 }
152 
mlx5e_xdp_is_active(struct mlx5e_priv * priv)153 static inline bool mlx5e_xdp_is_active(struct mlx5e_priv *priv)
154 {
155 	return test_bit(MLX5E_STATE_XDP_ACTIVE, &priv->state);
156 }
157 
mlx5e_xmit_xdp_doorbell(struct mlx5e_xdpsq * sq)158 static inline void mlx5e_xmit_xdp_doorbell(struct mlx5e_xdpsq *sq)
159 {
160 	if (sq->doorbell_cseg) {
161 		mlx5e_notify_hw(&sq->wq, sq->pc, sq->uar_map, sq->doorbell_cseg);
162 		sq->doorbell_cseg = NULL;
163 	}
164 }
165 
166 /* Enable inline WQEs to shift some load from a congested HCA (HW) to
167  * a less congested cpu (SW).
168  */
mlx5e_xdp_get_inline_state(struct mlx5e_xdpsq * sq,bool cur)169 static inline bool mlx5e_xdp_get_inline_state(struct mlx5e_xdpsq *sq, bool cur)
170 {
171 	u16 outstanding = sq->xdpi_fifo_pc - sq->xdpi_fifo_cc;
172 
173 #define MLX5E_XDP_INLINE_WATERMARK_LOW	10
174 #define MLX5E_XDP_INLINE_WATERMARK_HIGH 128
175 
176 	if (cur && outstanding <= MLX5E_XDP_INLINE_WATERMARK_LOW)
177 		return false;
178 
179 	if (!cur && outstanding >= MLX5E_XDP_INLINE_WATERMARK_HIGH)
180 		return true;
181 
182 	return cur;
183 }
184 
mlx5e_xdp_mpwqe_is_full(struct mlx5e_tx_mpwqe * session,u8 max_sq_mpw_wqebbs)185 static inline bool mlx5e_xdp_mpwqe_is_full(struct mlx5e_tx_mpwqe *session, u8 max_sq_mpw_wqebbs)
186 {
187 	if (session->inline_on)
188 		return session->ds_count + MLX5E_XDP_INLINE_WQE_MAX_DS_CNT >
189 		       max_sq_mpw_wqebbs * MLX5_SEND_WQEBB_NUM_DS;
190 
191 	return mlx5e_tx_mpwqe_is_full(session, max_sq_mpw_wqebbs);
192 }
193 
194 struct mlx5e_xdp_wqe_info {
195 	u8 num_wqebbs;
196 	u8 num_pkts;
197 };
198 
199 static inline void
mlx5e_xdp_mpwqe_add_dseg(struct mlx5e_xdpsq * sq,struct mlx5e_xmit_data * xdptxd,struct mlx5e_xdpsq_stats * stats)200 mlx5e_xdp_mpwqe_add_dseg(struct mlx5e_xdpsq *sq,
201 			 struct mlx5e_xmit_data *xdptxd,
202 			 struct mlx5e_xdpsq_stats *stats)
203 {
204 	struct mlx5e_tx_mpwqe *session = &sq->mpwqe;
205 	struct mlx5_wqe_data_seg *dseg =
206 		(struct mlx5_wqe_data_seg *)session->wqe + session->ds_count;
207 	u32 dma_len = xdptxd->len;
208 
209 	session->pkt_count++;
210 	session->bytes_count += dma_len;
211 
212 	if (session->inline_on && dma_len <= MLX5E_XDP_INLINE_WQE_SZ_THRSD) {
213 		struct mlx5_wqe_inline_seg *inline_dseg =
214 			(struct mlx5_wqe_inline_seg *)dseg;
215 		u16 ds_len = sizeof(*inline_dseg) + dma_len;
216 		u16 ds_cnt = DIV_ROUND_UP(ds_len, MLX5_SEND_WQE_DS);
217 
218 		inline_dseg->byte_count = cpu_to_be32(dma_len | MLX5_INLINE_SEG);
219 		memcpy(inline_dseg->data, xdptxd->data, dma_len);
220 
221 		session->ds_count += ds_cnt;
222 		stats->inlnw++;
223 		return;
224 	}
225 
226 	dseg->addr       = cpu_to_be64(xdptxd->dma_addr);
227 	dseg->byte_count = cpu_to_be32(dma_len);
228 	dseg->lkey       = sq->mkey_be;
229 	session->ds_count++;
230 }
231 
232 static inline void
mlx5e_xdpi_fifo_push(struct mlx5e_xdp_info_fifo * fifo,union mlx5e_xdp_info xi)233 mlx5e_xdpi_fifo_push(struct mlx5e_xdp_info_fifo *fifo,
234 		     union mlx5e_xdp_info xi)
235 {
236 	u32 i = (*fifo->pc)++ & fifo->mask;
237 
238 	fifo->xi[i] = xi;
239 }
240 
241 static inline union mlx5e_xdp_info
mlx5e_xdpi_fifo_pop(struct mlx5e_xdp_info_fifo * fifo)242 mlx5e_xdpi_fifo_pop(struct mlx5e_xdp_info_fifo *fifo)
243 {
244 	return fifo->xi[(*fifo->cc)++ & fifo->mask];
245 }
246 #endif
247