cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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igc_xdp.c (3642B)


      1// SPDX-License-Identifier: GPL-2.0
      2/* Copyright (c) 2020, Intel Corporation. */
      3
      4#include <linux/if_vlan.h>
      5#include <net/xdp_sock_drv.h>
      6
      7#include "igc.h"
      8#include "igc_xdp.h"
      9
     10int igc_xdp_set_prog(struct igc_adapter *adapter, struct bpf_prog *prog,
     11		     struct netlink_ext_ack *extack)
     12{
     13	struct net_device *dev = adapter->netdev;
     14	bool if_running = netif_running(dev);
     15	struct bpf_prog *old_prog;
     16
     17	if (dev->mtu > ETH_DATA_LEN) {
     18		/* For now, the driver doesn't support XDP functionality with
     19		 * jumbo frames so we return error.
     20		 */
     21		NL_SET_ERR_MSG_MOD(extack, "Jumbo frames not supported");
     22		return -EOPNOTSUPP;
     23	}
     24
     25	if (if_running)
     26		igc_close(dev);
     27
     28	old_prog = xchg(&adapter->xdp_prog, prog);
     29	if (old_prog)
     30		bpf_prog_put(old_prog);
     31
     32	if (if_running)
     33		igc_open(dev);
     34
     35	return 0;
     36}
     37
     38static int igc_xdp_enable_pool(struct igc_adapter *adapter,
     39			       struct xsk_buff_pool *pool, u16 queue_id)
     40{
     41	struct net_device *ndev = adapter->netdev;
     42	struct device *dev = &adapter->pdev->dev;
     43	struct igc_ring *rx_ring, *tx_ring;
     44	struct napi_struct *napi;
     45	bool needs_reset;
     46	u32 frame_size;
     47	int err;
     48
     49	if (queue_id >= adapter->num_rx_queues ||
     50	    queue_id >= adapter->num_tx_queues)
     51		return -EINVAL;
     52
     53	frame_size = xsk_pool_get_rx_frame_size(pool);
     54	if (frame_size < ETH_FRAME_LEN + VLAN_HLEN * 2) {
     55		/* When XDP is enabled, the driver doesn't support frames that
     56		 * span over multiple buffers. To avoid that, we check if xsk
     57		 * frame size is big enough to fit the max ethernet frame size
     58		 * + vlan double tagging.
     59		 */
     60		return -EOPNOTSUPP;
     61	}
     62
     63	err = xsk_pool_dma_map(pool, dev, IGC_RX_DMA_ATTR);
     64	if (err) {
     65		netdev_err(ndev, "Failed to map xsk pool\n");
     66		return err;
     67	}
     68
     69	needs_reset = netif_running(adapter->netdev) && igc_xdp_is_enabled(adapter);
     70
     71	rx_ring = adapter->rx_ring[queue_id];
     72	tx_ring = adapter->tx_ring[queue_id];
     73	/* Rx and Tx rings share the same napi context. */
     74	napi = &rx_ring->q_vector->napi;
     75
     76	if (needs_reset) {
     77		igc_disable_rx_ring(rx_ring);
     78		igc_disable_tx_ring(tx_ring);
     79		napi_disable(napi);
     80	}
     81
     82	set_bit(IGC_RING_FLAG_AF_XDP_ZC, &rx_ring->flags);
     83	set_bit(IGC_RING_FLAG_AF_XDP_ZC, &tx_ring->flags);
     84
     85	if (needs_reset) {
     86		napi_enable(napi);
     87		igc_enable_rx_ring(rx_ring);
     88		igc_enable_tx_ring(tx_ring);
     89
     90		err = igc_xsk_wakeup(ndev, queue_id, XDP_WAKEUP_RX);
     91		if (err) {
     92			xsk_pool_dma_unmap(pool, IGC_RX_DMA_ATTR);
     93			return err;
     94		}
     95	}
     96
     97	return 0;
     98}
     99
    100static int igc_xdp_disable_pool(struct igc_adapter *adapter, u16 queue_id)
    101{
    102	struct igc_ring *rx_ring, *tx_ring;
    103	struct xsk_buff_pool *pool;
    104	struct napi_struct *napi;
    105	bool needs_reset;
    106
    107	if (queue_id >= adapter->num_rx_queues ||
    108	    queue_id >= adapter->num_tx_queues)
    109		return -EINVAL;
    110
    111	pool = xsk_get_pool_from_qid(adapter->netdev, queue_id);
    112	if (!pool)
    113		return -EINVAL;
    114
    115	needs_reset = netif_running(adapter->netdev) && igc_xdp_is_enabled(adapter);
    116
    117	rx_ring = adapter->rx_ring[queue_id];
    118	tx_ring = adapter->tx_ring[queue_id];
    119	/* Rx and Tx rings share the same napi context. */
    120	napi = &rx_ring->q_vector->napi;
    121
    122	if (needs_reset) {
    123		igc_disable_rx_ring(rx_ring);
    124		igc_disable_tx_ring(tx_ring);
    125		napi_disable(napi);
    126	}
    127
    128	xsk_pool_dma_unmap(pool, IGC_RX_DMA_ATTR);
    129	clear_bit(IGC_RING_FLAG_AF_XDP_ZC, &rx_ring->flags);
    130	clear_bit(IGC_RING_FLAG_AF_XDP_ZC, &tx_ring->flags);
    131
    132	if (needs_reset) {
    133		napi_enable(napi);
    134		igc_enable_rx_ring(rx_ring);
    135		igc_enable_tx_ring(tx_ring);
    136	}
    137
    138	return 0;
    139}
    140
    141int igc_xdp_setup_pool(struct igc_adapter *adapter, struct xsk_buff_pool *pool,
    142		       u16 queue_id)
    143{
    144	return pool ? igc_xdp_enable_pool(adapter, pool, queue_id) :
    145		      igc_xdp_disable_pool(adapter, queue_id);
    146}