blob: f77a2d3ef37ecaa566be2458df36b56499984818 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/****************************************************************************
* Driver for Solarflare network controllers and boards
* Copyright 2005-2006 Fen Systems Ltd.
* Copyright 2005-2013 Solarflare Communications Inc.
*/
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/slab.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/prefetch.h>
#include <linux/moduleparam.h>
#include <linux/iommu.h>
#include <net/ip.h>
#include <net/checksum.h>
#include <net/xdp.h>
#include <linux/bpf_trace.h>
#include "net_driver.h"
#include "efx.h"
#include "rx_common.h"
#include "filter.h"
#include "nic.h"
#include "selftest.h"
#include "workarounds.h"
/* Preferred number of descriptors to fill at once */
#define EFX_RX_PREFERRED_BATCH 8U
/* Maximum rx prefix used by any architecture. */
#define EFX_MAX_RX_PREFIX_SIZE 16
/* Size of buffer allocated for skb header area. */
#define EFX_SKB_HEADERS 128u
/* Each packet can consume up to ceil(max_frame_len / buffer_size) buffers */
#define EFX_RX_MAX_FRAGS DIV_ROUND_UP(EFX_MAX_FRAME_LEN(EFX_MAX_MTU), \
EFX_RX_USR_BUF_SIZE)
static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue,
struct efx_rx_buffer *rx_buf,
int len)
{
struct efx_nic *efx = rx_queue->efx;
unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
if (likely(len <= max_len))
return;
/* The packet must be discarded, but this is only a fatal error
* if the caller indicated it was
*/
rx_buf->flags |= EFX_RX_PKT_DISCARD;
if (net_ratelimit())
netif_err(efx, rx_err, efx->net_dev,
"RX queue %d overlength RX event (%#x > %#x)\n",
efx_rx_queue_index(rx_queue), len, max_len);
efx_rx_queue_channel(rx_queue)->n_rx_overlength++;
}
/* Allocate and construct an SKB around page fragments */
static struct sk_buff *efx_rx_mk_skb(struct efx_channel *channel,
struct efx_rx_buffer *rx_buf,
unsigned int n_frags,
u8 *eh, int hdr_len)
{
struct efx_nic *efx = channel->efx;
struct sk_buff *skb;
/* Allocate an SKB to store the headers */
skb = netdev_alloc_skb(efx->net_dev,
efx->rx_ip_align + efx->rx_prefix_size +
hdr_len);
if (unlikely(skb == NULL)) {
atomic_inc(&efx->n_rx_noskb_drops);
return NULL;
}
EFX_WARN_ON_ONCE_PARANOID(rx_buf->len < hdr_len);
memcpy(skb->data + efx->rx_ip_align, eh - efx->rx_prefix_size,
efx->rx_prefix_size + hdr_len);
skb_reserve(skb, efx->rx_ip_align + efx->rx_prefix_size);
__skb_put(skb, hdr_len);
/* Append the remaining page(s) onto the frag list */
if (rx_buf->len > hdr_len) {
rx_buf->page_offset += hdr_len;
rx_buf->len -= hdr_len;
for (;;) {
skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
rx_buf->page, rx_buf->page_offset,
rx_buf->len, efx->rx_buffer_truesize);
rx_buf->page = NULL;
if (skb_shinfo(skb)->nr_frags == n_frags)
break;
rx_buf = efx_rx_buf_next(&channel->rx_queue, rx_buf);
}
} else {
__free_pages(rx_buf->page, efx->rx_buffer_order);
rx_buf->page = NULL;
n_frags = 0;
}
/* Move past the ethernet header */
skb->protocol = eth_type_trans(skb, efx->net_dev);
skb_mark_napi_id(skb, &channel->napi_str);
return skb;
}
void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index,
unsigned int n_frags, unsigned int len, u16 flags)
{
struct efx_nic *efx = rx_queue->efx;
struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
struct efx_rx_buffer *rx_buf;
rx_queue->rx_packets++;
rx_buf = efx_rx_buffer(rx_queue, index);
rx_buf->flags |= flags;
/* Validate the number of fragments and completed length */
if (n_frags == 1) {
if (!(flags & EFX_RX_PKT_PREFIX_LEN))
efx_rx_packet__check_len(rx_queue, rx_buf, len);
} else if (unlikely(n_frags > EFX_RX_MAX_FRAGS) ||
unlikely(len <= (n_frags - 1) * efx->rx_dma_len) ||
unlikely(len > n_frags * efx->rx_dma_len) ||
unlikely(!efx->rx_scatter)) {
/* If this isn't an explicit discard request, either
* the hardware or the driver is broken.
*/
WARN_ON(!(len == 0 && rx_buf->flags & EFX_RX_PKT_DISCARD));
rx_buf->flags |= EFX_RX_PKT_DISCARD;
}
netif_vdbg(efx, rx_status, efx->net_dev,
"RX queue %d received ids %x-%x len %d %s%s\n",
efx_rx_queue_index(rx_queue), index,
(index + n_frags - 1) & rx_queue->ptr_mask, len,
(rx_buf->flags & EFX_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
(rx_buf->flags & EFX_RX_PKT_DISCARD) ? " [DISCARD]" : "");
/* Discard packet, if instructed to do so. Process the
* previous receive first.
*/
if (unlikely(rx_buf->flags & EFX_RX_PKT_DISCARD)) {
efx_rx_flush_packet(channel);
efx_discard_rx_packet(channel, rx_buf, n_frags);
return;
}
if (n_frags == 1 && !(flags & EFX_RX_PKT_PREFIX_LEN))
rx_buf->len = len;
/* Release and/or sync the DMA mapping - assumes all RX buffers
* consumed in-order per RX queue.
*/
efx_sync_rx_buffer(efx, rx_buf, rx_buf->len);
/* Prefetch nice and early so data will (hopefully) be in cache by
* the time we look at it.
*/
prefetch(efx_rx_buf_va(rx_buf));
rx_buf->page_offset += efx->rx_prefix_size;
rx_buf->len -= efx->rx_prefix_size;
if (n_frags > 1) {
/* Release/sync DMA mapping for additional fragments.
* Fix length for last fragment.
*/
unsigned int tail_frags = n_frags - 1;
for (;;) {
rx_buf = efx_rx_buf_next(rx_queue, rx_buf);
if (--tail_frags == 0)
break;
efx_sync_rx_buffer(efx, rx_buf, efx->rx_dma_len);
}
rx_buf->len = len - (n_frags - 1) * efx->rx_dma_len;
efx_sync_rx_buffer(efx, rx_buf, rx_buf->len);
}
/* All fragments have been DMA-synced, so recycle pages. */
rx_buf = efx_rx_buffer(rx_queue, index);
efx_recycle_rx_pages(channel, rx_buf, n_frags);
/* Pipeline receives so that we give time for packet headers to be
* prefetched into cache.
*/
efx_rx_flush_packet(channel);
channel->rx_pkt_n_frags = n_frags;
channel->rx_pkt_index = index;
}
static void efx_rx_deliver(struct efx_channel *channel, u8 *eh,
struct efx_rx_buffer *rx_buf,
unsigned int n_frags)
{
struct sk_buff *skb;
u16 hdr_len = min_t(u16, rx_buf->len, EFX_SKB_HEADERS);
skb = efx_rx_mk_skb(channel, rx_buf, n_frags, eh, hdr_len);
if (unlikely(skb == NULL)) {
struct efx_rx_queue *rx_queue;
rx_queue = efx_channel_get_rx_queue(channel);
efx_free_rx_buffers(rx_queue, rx_buf, n_frags);
return;
}
skb_record_rx_queue(skb, channel->rx_queue.core_index);
/* Set the SKB flags */
skb_checksum_none_assert(skb);
if (likely(rx_buf->flags & EFX_RX_PKT_CSUMMED)) {
skb->ip_summed = CHECKSUM_UNNECESSARY;
skb->csum_level = !!(rx_buf->flags & EFX_RX_PKT_CSUM_LEVEL);
}
efx_rx_skb_attach_timestamp(channel, skb);
if (channel->type->receive_skb)
if (channel->type->receive_skb(channel, skb))
return;
/* Pass the packet up */
if (channel->rx_list != NULL)
/* Add to list, will pass up later */
list_add_tail(&skb->list, channel->rx_list);
else
/* No list, so pass it up now */
netif_receive_skb(skb);
}
/** efx_do_xdp: perform XDP processing on a received packet
*
* Returns true if packet should still be delivered.
*/
static bool efx_do_xdp(struct efx_nic *efx, struct efx_channel *channel,
struct efx_rx_buffer *rx_buf, u8 **ehp)
{
u8 rx_prefix[EFX_MAX_RX_PREFIX_SIZE];
struct efx_rx_queue *rx_queue;
struct bpf_prog *xdp_prog;
struct xdp_frame *xdpf;
struct xdp_buff xdp;
u32 xdp_act;
s16 offset;
int err;
xdp_prog = rcu_dereference_bh(efx->xdp_prog);
if (!xdp_prog)
return true;
rx_queue = efx_channel_get_rx_queue(channel);
if (unlikely(channel->rx_pkt_n_frags > 1)) {
/* We can't do XDP on fragmented packets - drop. */
efx_free_rx_buffers(rx_queue, rx_buf,
channel->rx_pkt_n_frags);
if (net_ratelimit())
netif_err(efx, rx_err, efx->net_dev,
"XDP is not possible with multiple receive fragments (%d)\n",
channel->rx_pkt_n_frags);
channel->n_rx_xdp_bad_drops++;
return false;
}
dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr,
rx_buf->len, DMA_FROM_DEVICE);
/* Save the rx prefix. */
EFX_WARN_ON_PARANOID(efx->rx_prefix_size > EFX_MAX_RX_PREFIX_SIZE);
memcpy(rx_prefix, *ehp - efx->rx_prefix_size,
efx->rx_prefix_size);
xdp_init_buff(&xdp, efx->rx_page_buf_step, &rx_queue->xdp_rxq_info);
/* No support yet for XDP metadata */
xdp_prepare_buff(&xdp, *ehp - EFX_XDP_HEADROOM, EFX_XDP_HEADROOM,
rx_buf->len, false);
xdp_act = bpf_prog_run_xdp(xdp_prog, &xdp);
offset = (u8 *)xdp.data - *ehp;
switch (xdp_act) {
case XDP_PASS:
/* Fix up rx prefix. */
if (offset) {
*ehp += offset;
rx_buf->page_offset += offset;
rx_buf->len -= offset;
memcpy(*ehp - efx->rx_prefix_size, rx_prefix,
efx->rx_prefix_size);
}
break;
case XDP_TX:
/* Buffer ownership passes to tx on success. */
xdpf = xdp_convert_buff_to_frame(&xdp);
err = efx_xdp_tx_buffers(efx, 1, &xdpf, true);
if (unlikely(err != 1)) {
efx_free_rx_buffers(rx_queue, rx_buf, 1);
if (net_ratelimit())
netif_err(efx, rx_err, efx->net_dev,
"XDP TX failed (%d)\n", err);
channel->n_rx_xdp_bad_drops++;
trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act);
} else {
channel->n_rx_xdp_tx++;
}
break;
case XDP_REDIRECT:
err = xdp_do_redirect(efx->net_dev, &xdp, xdp_prog);
if (unlikely(err)) {
efx_free_rx_buffers(rx_queue, rx_buf, 1);
if (net_ratelimit())
netif_err(efx, rx_err, efx->net_dev,
"XDP redirect failed (%d)\n", err);
channel->n_rx_xdp_bad_drops++;
trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act);
} else {
channel->n_rx_xdp_redirect++;
}
break;
default:
bpf_warn_invalid_xdp_action(efx->net_dev, xdp_prog, xdp_act);
efx_free_rx_buffers(rx_queue, rx_buf, 1);
channel->n_rx_xdp_bad_drops++;
trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act);
break;
case XDP_ABORTED:
trace_xdp_exception(efx->net_dev, xdp_prog, xdp_act);
fallthrough;
case XDP_DROP:
efx_free_rx_buffers(rx_queue, rx_buf, 1);
channel->n_rx_xdp_drops++;
break;
}
return xdp_act == XDP_PASS;
}
/* Handle a received packet. Second half: Touches packet payload. */
void __efx_rx_packet(struct efx_channel *channel)
{
struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
struct efx_nic *efx = channel->efx;
struct efx_rx_buffer *rx_buf =
efx_rx_buffer(rx_queue, channel->rx_pkt_index);
u8 *eh = efx_rx_buf_va(rx_buf);
/* Read length from the prefix if necessary. This already
* excludes the length of the prefix itself.
*/
if (rx_buf->flags & EFX_RX_PKT_PREFIX_LEN) {
rx_buf->len = le16_to_cpup((__le16 *)
(eh + efx->rx_packet_len_offset));
/* A known issue may prevent this being filled in;
* if that happens, just drop the packet.
* Must do that in the driver since passing a zero-length
* packet up to the stack may cause a crash.
*/
if (unlikely(!rx_buf->len)) {
efx_free_rx_buffers(rx_queue, rx_buf,
channel->rx_pkt_n_frags);
channel->n_rx_frm_trunc++;
goto out;
}
}
/* If we're in loopback test, then pass the packet directly to the
* loopback layer, and free the rx_buf here
*/
if (unlikely(efx->loopback_selftest)) {
efx_loopback_rx_packet(efx, eh, rx_buf->len);
efx_free_rx_buffers(rx_queue, rx_buf,
channel->rx_pkt_n_frags);
goto out;
}
if (!efx_do_xdp(efx, channel, rx_buf, &eh))
goto out;
if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
rx_buf->flags &= ~EFX_RX_PKT_CSUMMED;
if ((rx_buf->flags & EFX_RX_PKT_TCP) && !channel->type->receive_skb)
efx_rx_packet_gro(channel, rx_buf, channel->rx_pkt_n_frags, eh, 0);
else
efx_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags);
out:
channel->rx_pkt_n_frags = 0;
}