OpenCloudOS-Kernel/drivers/net/ethernet/sfc/rx.c

654 lines
19 KiB
C

// 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 inline void efx_sync_rx_buffer(struct efx_nic *efx,
struct efx_rx_buffer *rx_buf,
unsigned int len)
{
dma_sync_single_for_cpu(&efx->pci_dev->dev, rx_buf->dma_addr, len,
DMA_FROM_DEVICE);
}
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_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
rx_buf->page, rx_buf->page_offset,
rx_buf->len);
rx_buf->page = NULL;
skb->len += rx_buf->len;
skb->data_len += rx_buf->len;
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;
}
skb->truesize += n_frags * efx->rx_buffer_truesize;
/* 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;
rcu_read_lock();
xdp_prog = rcu_dereference(efx->xdp_prog);
if (!xdp_prog) {
rcu_read_unlock();
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. */
rcu_read_unlock();
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.data = *ehp;
xdp.data_hard_start = xdp.data - EFX_XDP_HEADROOM;
/* No support yet for XDP metadata */
xdp_set_data_meta_invalid(&xdp);
xdp.data_end = xdp.data + rx_buf->len;
xdp.rxq = &rx_queue->xdp_rxq_info;
xdp.frame_sz = efx->rx_page_buf_step;
xdp_act = bpf_prog_run_xdp(xdp_prog, &xdp);
rcu_read_unlock();
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(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);
/* Fall through */
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_nic *efx = channel->efx;
struct efx_rx_buffer *rx_buf =
efx_rx_buffer(&channel->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));
/* 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)) {
struct efx_rx_queue *rx_queue;
efx_loopback_rx_packet(efx, eh, rx_buf->len);
rx_queue = efx_channel_get_rx_queue(channel);
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);
else
efx_rx_deliver(channel, eh, rx_buf, channel->rx_pkt_n_frags);
out:
channel->rx_pkt_n_frags = 0;
}
#ifdef CONFIG_RFS_ACCEL
static void efx_filter_rfs_work(struct work_struct *data)
{
struct efx_async_filter_insertion *req = container_of(data, struct efx_async_filter_insertion,
work);
struct efx_nic *efx = netdev_priv(req->net_dev);
struct efx_channel *channel = efx_get_channel(efx, req->rxq_index);
int slot_idx = req - efx->rps_slot;
struct efx_arfs_rule *rule;
u16 arfs_id = 0;
int rc;
rc = efx->type->filter_insert(efx, &req->spec, true);
if (rc >= 0)
/* Discard 'priority' part of EF10+ filter ID (mcdi_filters) */
rc %= efx->type->max_rx_ip_filters;
if (efx->rps_hash_table) {
spin_lock_bh(&efx->rps_hash_lock);
rule = efx_rps_hash_find(efx, &req->spec);
/* The rule might have already gone, if someone else's request
* for the same spec was already worked and then expired before
* we got around to our work. In that case we have nothing
* tying us to an arfs_id, meaning that as soon as the filter
* is considered for expiry it will be removed.
*/
if (rule) {
if (rc < 0)
rule->filter_id = EFX_ARFS_FILTER_ID_ERROR;
else
rule->filter_id = rc;
arfs_id = rule->arfs_id;
}
spin_unlock_bh(&efx->rps_hash_lock);
}
if (rc >= 0) {
/* Remember this so we can check whether to expire the filter
* later.
*/
mutex_lock(&efx->rps_mutex);
if (channel->rps_flow_id[rc] == RPS_FLOW_ID_INVALID)
channel->rfs_filter_count++;
channel->rps_flow_id[rc] = req->flow_id;
mutex_unlock(&efx->rps_mutex);
if (req->spec.ether_type == htons(ETH_P_IP))
netif_info(efx, rx_status, efx->net_dev,
"steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d id %u]\n",
(req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
req->spec.rem_host, ntohs(req->spec.rem_port),
req->spec.loc_host, ntohs(req->spec.loc_port),
req->rxq_index, req->flow_id, rc, arfs_id);
else
netif_info(efx, rx_status, efx->net_dev,
"steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d id %u]\n",
(req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
req->spec.rem_host, ntohs(req->spec.rem_port),
req->spec.loc_host, ntohs(req->spec.loc_port),
req->rxq_index, req->flow_id, rc, arfs_id);
channel->n_rfs_succeeded++;
} else {
if (req->spec.ether_type == htons(ETH_P_IP))
netif_dbg(efx, rx_status, efx->net_dev,
"failed to steer %s %pI4:%u:%pI4:%u to queue %u [flow %u rc %d id %u]\n",
(req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
req->spec.rem_host, ntohs(req->spec.rem_port),
req->spec.loc_host, ntohs(req->spec.loc_port),
req->rxq_index, req->flow_id, rc, arfs_id);
else
netif_dbg(efx, rx_status, efx->net_dev,
"failed to steer %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u rc %d id %u]\n",
(req->spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
req->spec.rem_host, ntohs(req->spec.rem_port),
req->spec.loc_host, ntohs(req->spec.loc_port),
req->rxq_index, req->flow_id, rc, arfs_id);
channel->n_rfs_failed++;
/* We're overloading the NIC's filter tables, so let's do a
* chunk of extra expiry work.
*/
__efx_filter_rfs_expire(channel, min(channel->rfs_filter_count,
100u));
}
/* Release references */
clear_bit(slot_idx, &efx->rps_slot_map);
dev_put(req->net_dev);
}
int efx_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
u16 rxq_index, u32 flow_id)
{
struct efx_nic *efx = netdev_priv(net_dev);
struct efx_async_filter_insertion *req;
struct efx_arfs_rule *rule;
struct flow_keys fk;
int slot_idx;
bool new;
int rc;
/* find a free slot */
for (slot_idx = 0; slot_idx < EFX_RPS_MAX_IN_FLIGHT; slot_idx++)
if (!test_and_set_bit(slot_idx, &efx->rps_slot_map))
break;
if (slot_idx >= EFX_RPS_MAX_IN_FLIGHT)
return -EBUSY;
if (flow_id == RPS_FLOW_ID_INVALID) {
rc = -EINVAL;
goto out_clear;
}
if (!skb_flow_dissect_flow_keys(skb, &fk, 0)) {
rc = -EPROTONOSUPPORT;
goto out_clear;
}
if (fk.basic.n_proto != htons(ETH_P_IP) && fk.basic.n_proto != htons(ETH_P_IPV6)) {
rc = -EPROTONOSUPPORT;
goto out_clear;
}
if (fk.control.flags & FLOW_DIS_IS_FRAGMENT) {
rc = -EPROTONOSUPPORT;
goto out_clear;
}
req = efx->rps_slot + slot_idx;
efx_filter_init_rx(&req->spec, EFX_FILTER_PRI_HINT,
efx->rx_scatter ? EFX_FILTER_FLAG_RX_SCATTER : 0,
rxq_index);
req->spec.match_flags =
EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_IP_PROTO |
EFX_FILTER_MATCH_LOC_HOST | EFX_FILTER_MATCH_LOC_PORT |
EFX_FILTER_MATCH_REM_HOST | EFX_FILTER_MATCH_REM_PORT;
req->spec.ether_type = fk.basic.n_proto;
req->spec.ip_proto = fk.basic.ip_proto;
if (fk.basic.n_proto == htons(ETH_P_IP)) {
req->spec.rem_host[0] = fk.addrs.v4addrs.src;
req->spec.loc_host[0] = fk.addrs.v4addrs.dst;
} else {
memcpy(req->spec.rem_host, &fk.addrs.v6addrs.src,
sizeof(struct in6_addr));
memcpy(req->spec.loc_host, &fk.addrs.v6addrs.dst,
sizeof(struct in6_addr));
}
req->spec.rem_port = fk.ports.src;
req->spec.loc_port = fk.ports.dst;
if (efx->rps_hash_table) {
/* Add it to ARFS hash table */
spin_lock(&efx->rps_hash_lock);
rule = efx_rps_hash_add(efx, &req->spec, &new);
if (!rule) {
rc = -ENOMEM;
goto out_unlock;
}
if (new)
rule->arfs_id = efx->rps_next_id++ % RPS_NO_FILTER;
rc = rule->arfs_id;
/* Skip if existing or pending filter already does the right thing */
if (!new && rule->rxq_index == rxq_index &&
rule->filter_id >= EFX_ARFS_FILTER_ID_PENDING)
goto out_unlock;
rule->rxq_index = rxq_index;
rule->filter_id = EFX_ARFS_FILTER_ID_PENDING;
spin_unlock(&efx->rps_hash_lock);
} else {
/* Without an ARFS hash table, we just use arfs_id 0 for all
* filters. This means if multiple flows hash to the same
* flow_id, all but the most recently touched will be eligible
* for expiry.
*/
rc = 0;
}
/* Queue the request */
dev_hold(req->net_dev = net_dev);
INIT_WORK(&req->work, efx_filter_rfs_work);
req->rxq_index = rxq_index;
req->flow_id = flow_id;
schedule_work(&req->work);
return rc;
out_unlock:
spin_unlock(&efx->rps_hash_lock);
out_clear:
clear_bit(slot_idx, &efx->rps_slot_map);
return rc;
}
bool __efx_filter_rfs_expire(struct efx_channel *channel, unsigned int quota)
{
bool (*expire_one)(struct efx_nic *efx, u32 flow_id, unsigned int index);
struct efx_nic *efx = channel->efx;
unsigned int index, size, start;
u32 flow_id;
if (!mutex_trylock(&efx->rps_mutex))
return false;
expire_one = efx->type->filter_rfs_expire_one;
index = channel->rfs_expire_index;
start = index;
size = efx->type->max_rx_ip_filters;
while (quota) {
flow_id = channel->rps_flow_id[index];
if (flow_id != RPS_FLOW_ID_INVALID) {
quota--;
if (expire_one(efx, flow_id, index)) {
netif_info(efx, rx_status, efx->net_dev,
"expired filter %d [channel %u flow %u]\n",
index, channel->channel, flow_id);
channel->rps_flow_id[index] = RPS_FLOW_ID_INVALID;
channel->rfs_filter_count--;
}
}
if (++index == size)
index = 0;
/* If we were called with a quota that exceeds the total number
* of filters in the table (which shouldn't happen, but could
* if two callers race), ensure that we don't loop forever -
* stop when we've examined every row of the table.
*/
if (index == start)
break;
}
channel->rfs_expire_index = index;
mutex_unlock(&efx->rps_mutex);
return true;
}
#endif /* CONFIG_RFS_ACCEL */