xref: /linux/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c (revision 621cde16e49b3ecf7d59a8106a20aaebfb4a59a9)
1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2 /* Copyright (c) 2019 Mellanox Technologies. */
3 
4 #include "setup.h"
5 #include "en/params.h"
6 #include "en/txrx.h"
7 #include "en/health.h"
8 #include <net/xdp_sock_drv.h>
9 
mlx5e_legacy_rq_validate_xsk(struct mlx5_core_dev * mdev,struct mlx5e_params * params,struct mlx5e_xsk_param * xsk)10 static int mlx5e_legacy_rq_validate_xsk(struct mlx5_core_dev *mdev,
11 					struct mlx5e_params *params,
12 					struct mlx5e_xsk_param *xsk)
13 {
14 	if (!mlx5e_rx_is_linear_skb(mdev, params, xsk)) {
15 		mlx5_core_err(mdev, "Legacy RQ linear mode for XSK can't be activated with current params\n");
16 		return -EINVAL;
17 	}
18 
19 	return 0;
20 }
21 
22 /* The limitation of 2048 can be altered, but shouldn't go beyond the minimal
23  * stride size of striding RQ.
24  */
25 #define MLX5E_MIN_XSK_CHUNK_SIZE max(2048, XDP_UMEM_MIN_CHUNK_SIZE)
26 
mlx5e_validate_xsk_param(struct mlx5e_params * params,struct mlx5e_xsk_param * xsk,struct mlx5_core_dev * mdev)27 bool mlx5e_validate_xsk_param(struct mlx5e_params *params,
28 			      struct mlx5e_xsk_param *xsk,
29 			      struct mlx5_core_dev *mdev)
30 {
31 	/* AF_XDP doesn't support frames larger than PAGE_SIZE,
32 	 * and xsk->chunk_size is limited to 65535 bytes.
33 	 */
34 	if ((size_t)xsk->chunk_size > PAGE_SIZE || xsk->chunk_size < MLX5E_MIN_XSK_CHUNK_SIZE) {
35 		mlx5_core_err(mdev, "XSK chunk size %u out of bounds [%u, %lu]\n", xsk->chunk_size,
36 			      MLX5E_MIN_XSK_CHUNK_SIZE, PAGE_SIZE);
37 		return false;
38 	}
39 
40 	/* frag_sz is different for regular and XSK RQs, so ensure that linear
41 	 * SKB mode is possible.
42 	 */
43 	switch (params->rq_wq_type) {
44 	case MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ:
45 		return !mlx5e_mpwrq_validate_xsk(mdev, params, xsk);
46 	default: /* MLX5_WQ_TYPE_CYCLIC */
47 		return !mlx5e_legacy_rq_validate_xsk(mdev, params, xsk);
48 	}
49 }
50 
mlx5e_build_xsk_cparam(struct mlx5_core_dev * mdev,struct mlx5e_params * params,struct mlx5e_xsk_param * xsk,struct mlx5e_channel_param * cparam)51 static void mlx5e_build_xsk_cparam(struct mlx5_core_dev *mdev,
52 				   struct mlx5e_params *params,
53 				   struct mlx5e_xsk_param *xsk,
54 				   struct mlx5e_channel_param *cparam)
55 {
56 	mlx5e_build_rq_param(mdev, params, xsk, &cparam->rq);
57 	mlx5e_build_xdpsq_param(mdev, params, xsk, &cparam->xdp_sq);
58 }
59 
mlx5e_init_xsk_rq(struct mlx5e_channel * c,struct mlx5e_params * params,struct xsk_buff_pool * pool,struct mlx5e_xsk_param * xsk,struct mlx5e_rq * rq)60 static int mlx5e_init_xsk_rq(struct mlx5e_channel *c,
61 			     struct mlx5e_params *params,
62 			     struct xsk_buff_pool *pool,
63 			     struct mlx5e_xsk_param *xsk,
64 			     struct mlx5e_rq *rq)
65 {
66 	struct mlx5_core_dev *mdev = c->mdev;
67 	int rq_xdp_ix;
68 	int err;
69 
70 	rq->wq_type      = params->rq_wq_type;
71 	rq->pdev         = c->pdev;
72 	rq->netdev       = c->netdev;
73 	rq->priv         = c->priv;
74 	rq->tstamp       = c->tstamp;
75 	rq->clock        = &mdev->clock;
76 	rq->icosq        = &c->icosq;
77 	rq->ix           = c->ix;
78 	rq->channel      = c;
79 	rq->mdev         = mdev;
80 	rq->hw_mtu       = MLX5E_SW2HW_MTU(params, params->sw_mtu);
81 	rq->xdpsq        = &c->rq_xdpsq;
82 	rq->xsk_pool     = pool;
83 	rq->stats        = &c->priv->channel_stats[c->ix]->xskrq;
84 	rq->ptp_cyc2time = mlx5_rq_ts_translator(mdev);
85 	rq_xdp_ix        = c->ix;
86 	err = mlx5e_rq_set_handlers(rq, params, xsk);
87 	if (err)
88 		return err;
89 
90 	return xdp_rxq_info_reg(&rq->xdp_rxq, rq->netdev, rq_xdp_ix, c->napi.napi_id);
91 }
92 
mlx5e_open_xsk_rq(struct mlx5e_channel * c,struct mlx5e_params * params,struct mlx5e_rq_param * rq_params,struct xsk_buff_pool * pool,struct mlx5e_xsk_param * xsk)93 static int mlx5e_open_xsk_rq(struct mlx5e_channel *c, struct mlx5e_params *params,
94 			     struct mlx5e_rq_param *rq_params, struct xsk_buff_pool *pool,
95 			     struct mlx5e_xsk_param *xsk)
96 {
97 	u16 q_counter = c->priv->q_counter[c->sd_ix];
98 	struct mlx5e_rq *xskrq = &c->xskrq;
99 	int err;
100 
101 	err = mlx5e_init_xsk_rq(c, params, pool, xsk, xskrq);
102 	if (err)
103 		return err;
104 
105 	err = mlx5e_open_rq(params, rq_params, xsk, cpu_to_node(c->cpu), q_counter, xskrq);
106 	if (err)
107 		return err;
108 
109 	__set_bit(MLX5E_RQ_STATE_XSK, &xskrq->state);
110 	return 0;
111 }
112 
mlx5e_open_xsk(struct mlx5e_priv * priv,struct mlx5e_params * params,struct mlx5e_xsk_param * xsk,struct xsk_buff_pool * pool,struct mlx5e_channel * c)113 int mlx5e_open_xsk(struct mlx5e_priv *priv, struct mlx5e_params *params,
114 		   struct mlx5e_xsk_param *xsk, struct xsk_buff_pool *pool,
115 		   struct mlx5e_channel *c)
116 {
117 	struct mlx5e_channel_param *cparam;
118 	struct mlx5e_create_cq_param ccp;
119 	int err;
120 
121 	mlx5e_build_create_cq_param(&ccp, c);
122 
123 	if (!mlx5e_validate_xsk_param(params, xsk, priv->mdev))
124 		return -EINVAL;
125 
126 	cparam = kvzalloc(sizeof(*cparam), GFP_KERNEL);
127 	if (!cparam)
128 		return -ENOMEM;
129 
130 	mlx5e_build_xsk_cparam(priv->mdev, params, xsk, cparam);
131 
132 	err = mlx5e_open_cq(c->mdev, params->rx_cq_moderation, &cparam->rq.cqp, &ccp,
133 			    &c->xskrq.cq);
134 	if (unlikely(err))
135 		goto err_free_cparam;
136 
137 	err = mlx5e_open_xsk_rq(c, params, &cparam->rq, pool, xsk);
138 	if (unlikely(err))
139 		goto err_close_rx_cq;
140 
141 	err = mlx5e_open_cq(c->mdev, params->tx_cq_moderation, &cparam->xdp_sq.cqp, &ccp,
142 			    &c->xsksq.cq);
143 	if (unlikely(err))
144 		goto err_close_rq;
145 
146 	/* Create a separate SQ, so that when the buff pool is disabled, we could
147 	 * close this SQ safely and stop receiving CQEs. In other case, e.g., if
148 	 * the XDPSQ was used instead, we might run into trouble when the buff pool
149 	 * is disabled and then re-enabled, but the SQ continues receiving CQEs
150 	 * from the old buff pool.
151 	 */
152 	err = mlx5e_open_xdpsq(c, params, &cparam->xdp_sq, pool, &c->xsksq, true);
153 	if (unlikely(err))
154 		goto err_close_tx_cq;
155 
156 	kvfree(cparam);
157 
158 	set_bit(MLX5E_CHANNEL_STATE_XSK, c->state);
159 
160 	return 0;
161 
162 err_close_tx_cq:
163 	mlx5e_close_cq(&c->xsksq.cq);
164 
165 err_close_rq:
166 	mlx5e_close_rq(&c->xskrq);
167 
168 err_close_rx_cq:
169 	mlx5e_close_cq(&c->xskrq.cq);
170 
171 err_free_cparam:
172 	kvfree(cparam);
173 
174 	return err;
175 }
176 
mlx5e_close_xsk(struct mlx5e_channel * c)177 void mlx5e_close_xsk(struct mlx5e_channel *c)
178 {
179 	clear_bit(MLX5E_CHANNEL_STATE_XSK, c->state);
180 	synchronize_net(); /* Sync with NAPI. */
181 
182 	mlx5e_close_rq(&c->xskrq);
183 	mlx5e_close_cq(&c->xskrq.cq);
184 	mlx5e_close_xdpsq(&c->xsksq);
185 	mlx5e_close_cq(&c->xsksq.cq);
186 
187 	memset(&c->xskrq, 0, sizeof(c->xskrq));
188 	memset(&c->xsksq, 0, sizeof(c->xsksq));
189 }
190 
mlx5e_activate_xsk(struct mlx5e_channel * c)191 void mlx5e_activate_xsk(struct mlx5e_channel *c)
192 {
193 	/* ICOSQ recovery deactivates RQs. Suspend the recovery to avoid
194 	 * activating XSKRQ in the middle of recovery.
195 	 */
196 	mlx5e_reporter_icosq_suspend_recovery(c);
197 	set_bit(MLX5E_RQ_STATE_ENABLED, &c->xskrq.state);
198 	mlx5e_reporter_icosq_resume_recovery(c);
199 
200 	/* TX queue is created active. */
201 }
202 
mlx5e_deactivate_xsk(struct mlx5e_channel * c)203 void mlx5e_deactivate_xsk(struct mlx5e_channel *c)
204 {
205 	/* ICOSQ recovery may reactivate XSKRQ if clear_bit is called in the
206 	 * middle of recovery. Suspend the recovery to avoid it.
207 	 */
208 	mlx5e_reporter_icosq_suspend_recovery(c);
209 	clear_bit(MLX5E_RQ_STATE_ENABLED, &c->xskrq.state);
210 	mlx5e_reporter_icosq_resume_recovery(c);
211 	synchronize_net(); /* Sync with NAPI to prevent mlx5e_post_rx_wqes. */
212 
213 	/* TX queue is disabled on close. */
214 }
215