1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2021, Intel Corporation. */
3
4#include <net/xdp_sock_drv.h>
5
6#include "stmmac.h"
7#include "stmmac_xdp.h"
8
9static int stmmac_xdp_enable_pool(struct stmmac_priv *priv,
10				  struct xsk_buff_pool *pool, u16 queue)
11{
12	struct stmmac_channel *ch = &priv->channel[queue];
13	bool need_update;
14	u32 frame_size;
15	int err;
16
17	if (queue >= priv->plat->rx_queues_to_use ||
18	    queue >= priv->plat->tx_queues_to_use)
19		return -EINVAL;
20
21	frame_size = xsk_pool_get_rx_frame_size(pool);
22	/* XDP ZC does not span multiple frame, make sure XSK pool buffer
23	 * size can at least store Q-in-Q frame.
24	 */
25	if (frame_size < ETH_FRAME_LEN + VLAN_HLEN * 2)
26		return -EOPNOTSUPP;
27
28	err = xsk_pool_dma_map(pool, priv->device, STMMAC_RX_DMA_ATTR);
29	if (err) {
30		netdev_err(priv->dev, "Failed to map xsk pool\n");
31		return err;
32	}
33
34	need_update = netif_running(priv->dev) && stmmac_xdp_is_enabled(priv);
35
36	if (need_update) {
37		napi_disable(&ch->rx_napi);
38		napi_disable(&ch->tx_napi);
39		stmmac_disable_rx_queue(priv, queue);
40		stmmac_disable_tx_queue(priv, queue);
41	}
42
43	set_bit(queue, priv->af_xdp_zc_qps);
44
45	if (need_update) {
46		stmmac_enable_rx_queue(priv, queue);
47		stmmac_enable_tx_queue(priv, queue);
48		napi_enable(&ch->rxtx_napi);
49
50		err = stmmac_xsk_wakeup(priv->dev, queue, XDP_WAKEUP_RX);
51		if (err)
52			return err;
53	}
54
55	return 0;
56}
57
58static int stmmac_xdp_disable_pool(struct stmmac_priv *priv, u16 queue)
59{
60	struct stmmac_channel *ch = &priv->channel[queue];
61	struct xsk_buff_pool *pool;
62	bool need_update;
63
64	if (queue >= priv->plat->rx_queues_to_use ||
65	    queue >= priv->plat->tx_queues_to_use)
66		return -EINVAL;
67
68	pool = xsk_get_pool_from_qid(priv->dev, queue);
69	if (!pool)
70		return -EINVAL;
71
72	need_update = netif_running(priv->dev) && stmmac_xdp_is_enabled(priv);
73
74	if (need_update) {
75		napi_disable(&ch->rxtx_napi);
76		stmmac_disable_rx_queue(priv, queue);
77		stmmac_disable_tx_queue(priv, queue);
78		synchronize_rcu();
79	}
80
81	xsk_pool_dma_unmap(pool, STMMAC_RX_DMA_ATTR);
82
83	clear_bit(queue, priv->af_xdp_zc_qps);
84
85	if (need_update) {
86		stmmac_enable_rx_queue(priv, queue);
87		stmmac_enable_tx_queue(priv, queue);
88		napi_enable(&ch->rx_napi);
89		napi_enable(&ch->tx_napi);
90	}
91
92	return 0;
93}
94
95int stmmac_xdp_setup_pool(struct stmmac_priv *priv, struct xsk_buff_pool *pool,
96			  u16 queue)
97{
98	return pool ? stmmac_xdp_enable_pool(priv, pool, queue) :
99		      stmmac_xdp_disable_pool(priv, queue);
100}
101
102int stmmac_xdp_set_prog(struct stmmac_priv *priv, struct bpf_prog *prog,
103			struct netlink_ext_ack *extack)
104{
105	struct net_device *dev = priv->dev;
106	struct bpf_prog *old_prog;
107	bool need_update;
108	bool if_running;
109
110	if_running = netif_running(dev);
111
112	if (prog && dev->mtu > ETH_DATA_LEN) {
113		/* For now, the driver doesn't support XDP functionality with
114		 * jumbo frames so we return error.
115		 */
116		NL_SET_ERR_MSG_MOD(extack, "Jumbo frames not supported");
117		return -EOPNOTSUPP;
118	}
119
120	if (!prog)
121		xdp_features_clear_redirect_target(dev);
122
123	need_update = !!priv->xdp_prog != !!prog;
124	if (if_running && need_update)
125		stmmac_xdp_release(dev);
126
127	old_prog = xchg(&priv->xdp_prog, prog);
128	if (old_prog)
129		bpf_prog_put(old_prog);
130
131	/* Disable RX SPH for XDP operation */
132	priv->sph = priv->sph_cap && !stmmac_xdp_is_enabled(priv);
133
134	if (if_running && need_update)
135		stmmac_xdp_open(dev);
136
137	if (prog)
138		xdp_features_set_redirect_target(dev, false);
139
140	return 0;
141}
142