linux/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
Magnus Karlsson 9116e5e2b1 xsk: replace ndo_xsk_async_xmit with ndo_xsk_wakeup
This commit replaces ndo_xsk_async_xmit with ndo_xsk_wakeup. This new
ndo provides the same functionality as before but with the addition of
a new flags field that is used to specifiy if Rx, Tx or both should be
woken up. The previous ndo only woke up Tx, as implied by the
name. The i40e and ixgbe drivers (which are all the supported ones)
are updated with this new interface.

This new ndo will be used by the new need_wakeup functionality of XDP
sockets that need to be able to wake up both Rx and Tx driver
processing.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-17 23:07:31 +02:00

747 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2018 Intel Corporation. */
#include <linux/bpf_trace.h>
#include <net/xdp_sock.h>
#include <net/xdp.h>
#include "ixgbe.h"
#include "ixgbe_txrx_common.h"
struct xdp_umem *ixgbe_xsk_umem(struct ixgbe_adapter *adapter,
struct ixgbe_ring *ring)
{
bool xdp_on = READ_ONCE(adapter->xdp_prog);
int qid = ring->ring_idx;
if (!xdp_on || !test_bit(qid, adapter->af_xdp_zc_qps))
return NULL;
return xdp_get_umem_from_qid(adapter->netdev, qid);
}
static int ixgbe_xsk_umem_dma_map(struct ixgbe_adapter *adapter,
struct xdp_umem *umem)
{
struct device *dev = &adapter->pdev->dev;
unsigned int i, j;
dma_addr_t dma;
for (i = 0; i < umem->npgs; i++) {
dma = dma_map_page_attrs(dev, umem->pgs[i], 0, PAGE_SIZE,
DMA_BIDIRECTIONAL, IXGBE_RX_DMA_ATTR);
if (dma_mapping_error(dev, dma))
goto out_unmap;
umem->pages[i].dma = dma;
}
return 0;
out_unmap:
for (j = 0; j < i; j++) {
dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
DMA_BIDIRECTIONAL, IXGBE_RX_DMA_ATTR);
umem->pages[i].dma = 0;
}
return -1;
}
static void ixgbe_xsk_umem_dma_unmap(struct ixgbe_adapter *adapter,
struct xdp_umem *umem)
{
struct device *dev = &adapter->pdev->dev;
unsigned int i;
for (i = 0; i < umem->npgs; i++) {
dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
DMA_BIDIRECTIONAL, IXGBE_RX_DMA_ATTR);
umem->pages[i].dma = 0;
}
}
static int ixgbe_xsk_umem_enable(struct ixgbe_adapter *adapter,
struct xdp_umem *umem,
u16 qid)
{
struct net_device *netdev = adapter->netdev;
struct xdp_umem_fq_reuse *reuseq;
bool if_running;
int err;
if (qid >= adapter->num_rx_queues)
return -EINVAL;
if (qid >= netdev->real_num_rx_queues ||
qid >= netdev->real_num_tx_queues)
return -EINVAL;
reuseq = xsk_reuseq_prepare(adapter->rx_ring[0]->count);
if (!reuseq)
return -ENOMEM;
xsk_reuseq_free(xsk_reuseq_swap(umem, reuseq));
err = ixgbe_xsk_umem_dma_map(adapter, umem);
if (err)
return err;
if_running = netif_running(adapter->netdev) &&
ixgbe_enabled_xdp_adapter(adapter);
if (if_running)
ixgbe_txrx_ring_disable(adapter, qid);
set_bit(qid, adapter->af_xdp_zc_qps);
if (if_running) {
ixgbe_txrx_ring_enable(adapter, qid);
/* Kick start the NAPI context so that receiving will start */
err = ixgbe_xsk_wakeup(adapter->netdev, qid, XDP_WAKEUP_RX);
if (err)
return err;
}
return 0;
}
static int ixgbe_xsk_umem_disable(struct ixgbe_adapter *adapter, u16 qid)
{
struct xdp_umem *umem;
bool if_running;
umem = xdp_get_umem_from_qid(adapter->netdev, qid);
if (!umem)
return -EINVAL;
if_running = netif_running(adapter->netdev) &&
ixgbe_enabled_xdp_adapter(adapter);
if (if_running)
ixgbe_txrx_ring_disable(adapter, qid);
clear_bit(qid, adapter->af_xdp_zc_qps);
ixgbe_xsk_umem_dma_unmap(adapter, umem);
if (if_running)
ixgbe_txrx_ring_enable(adapter, qid);
return 0;
}
int ixgbe_xsk_umem_setup(struct ixgbe_adapter *adapter, struct xdp_umem *umem,
u16 qid)
{
return umem ? ixgbe_xsk_umem_enable(adapter, umem, qid) :
ixgbe_xsk_umem_disable(adapter, qid);
}
static int ixgbe_run_xdp_zc(struct ixgbe_adapter *adapter,
struct ixgbe_ring *rx_ring,
struct xdp_buff *xdp)
{
int err, result = IXGBE_XDP_PASS;
struct bpf_prog *xdp_prog;
struct xdp_frame *xdpf;
u32 act;
rcu_read_lock();
xdp_prog = READ_ONCE(rx_ring->xdp_prog);
act = bpf_prog_run_xdp(xdp_prog, xdp);
xdp->handle += xdp->data - xdp->data_hard_start;
switch (act) {
case XDP_PASS:
break;
case XDP_TX:
xdpf = convert_to_xdp_frame(xdp);
if (unlikely(!xdpf)) {
result = IXGBE_XDP_CONSUMED;
break;
}
result = ixgbe_xmit_xdp_ring(adapter, xdpf);
break;
case XDP_REDIRECT:
err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
result = !err ? IXGBE_XDP_REDIR : IXGBE_XDP_CONSUMED;
break;
default:
bpf_warn_invalid_xdp_action(act);
/* fallthrough */
case XDP_ABORTED:
trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
/* fallthrough -- handle aborts by dropping packet */
case XDP_DROP:
result = IXGBE_XDP_CONSUMED;
break;
}
rcu_read_unlock();
return result;
}
static struct
ixgbe_rx_buffer *ixgbe_get_rx_buffer_zc(struct ixgbe_ring *rx_ring,
unsigned int size)
{
struct ixgbe_rx_buffer *bi;
bi = &rx_ring->rx_buffer_info[rx_ring->next_to_clean];
/* we are reusing so sync this buffer for CPU use */
dma_sync_single_range_for_cpu(rx_ring->dev,
bi->dma, 0,
size,
DMA_BIDIRECTIONAL);
return bi;
}
static void ixgbe_reuse_rx_buffer_zc(struct ixgbe_ring *rx_ring,
struct ixgbe_rx_buffer *obi)
{
unsigned long mask = (unsigned long)rx_ring->xsk_umem->chunk_mask;
u64 hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
u16 nta = rx_ring->next_to_alloc;
struct ixgbe_rx_buffer *nbi;
nbi = &rx_ring->rx_buffer_info[rx_ring->next_to_alloc];
/* update, and store next to alloc */
nta++;
rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
/* transfer page from old buffer to new buffer */
nbi->dma = obi->dma & mask;
nbi->dma += hr;
nbi->addr = (void *)((unsigned long)obi->addr & mask);
nbi->addr += hr;
nbi->handle = obi->handle & mask;
nbi->handle += rx_ring->xsk_umem->headroom;
obi->addr = NULL;
obi->skb = NULL;
}
void ixgbe_zca_free(struct zero_copy_allocator *alloc, unsigned long handle)
{
struct ixgbe_rx_buffer *bi;
struct ixgbe_ring *rx_ring;
u64 hr, mask;
u16 nta;
rx_ring = container_of(alloc, struct ixgbe_ring, zca);
hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
mask = rx_ring->xsk_umem->chunk_mask;
nta = rx_ring->next_to_alloc;
bi = rx_ring->rx_buffer_info;
nta++;
rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
handle &= mask;
bi->dma = xdp_umem_get_dma(rx_ring->xsk_umem, handle);
bi->dma += hr;
bi->addr = xdp_umem_get_data(rx_ring->xsk_umem, handle);
bi->addr += hr;
bi->handle = (u64)handle + rx_ring->xsk_umem->headroom;
}
static bool ixgbe_alloc_buffer_zc(struct ixgbe_ring *rx_ring,
struct ixgbe_rx_buffer *bi)
{
struct xdp_umem *umem = rx_ring->xsk_umem;
void *addr = bi->addr;
u64 handle, hr;
if (addr)
return true;
if (!xsk_umem_peek_addr(umem, &handle)) {
rx_ring->rx_stats.alloc_rx_page_failed++;
return false;
}
hr = umem->headroom + XDP_PACKET_HEADROOM;
bi->dma = xdp_umem_get_dma(umem, handle);
bi->dma += hr;
bi->addr = xdp_umem_get_data(umem, handle);
bi->addr += hr;
bi->handle = handle + umem->headroom;
xsk_umem_discard_addr(umem);
return true;
}
static bool ixgbe_alloc_buffer_slow_zc(struct ixgbe_ring *rx_ring,
struct ixgbe_rx_buffer *bi)
{
struct xdp_umem *umem = rx_ring->xsk_umem;
u64 handle, hr;
if (!xsk_umem_peek_addr_rq(umem, &handle)) {
rx_ring->rx_stats.alloc_rx_page_failed++;
return false;
}
handle &= rx_ring->xsk_umem->chunk_mask;
hr = umem->headroom + XDP_PACKET_HEADROOM;
bi->dma = xdp_umem_get_dma(umem, handle);
bi->dma += hr;
bi->addr = xdp_umem_get_data(umem, handle);
bi->addr += hr;
bi->handle = handle + umem->headroom;
xsk_umem_discard_addr_rq(umem);
return true;
}
static __always_inline bool
__ixgbe_alloc_rx_buffers_zc(struct ixgbe_ring *rx_ring, u16 cleaned_count,
bool alloc(struct ixgbe_ring *rx_ring,
struct ixgbe_rx_buffer *bi))
{
union ixgbe_adv_rx_desc *rx_desc;
struct ixgbe_rx_buffer *bi;
u16 i = rx_ring->next_to_use;
bool ok = true;
/* nothing to do */
if (!cleaned_count)
return true;
rx_desc = IXGBE_RX_DESC(rx_ring, i);
bi = &rx_ring->rx_buffer_info[i];
i -= rx_ring->count;
do {
if (!alloc(rx_ring, bi)) {
ok = false;
break;
}
/* sync the buffer for use by the device */
dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
bi->page_offset,
rx_ring->rx_buf_len,
DMA_BIDIRECTIONAL);
/* Refresh the desc even if buffer_addrs didn't change
* because each write-back erases this info.
*/
rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
rx_desc++;
bi++;
i++;
if (unlikely(!i)) {
rx_desc = IXGBE_RX_DESC(rx_ring, 0);
bi = rx_ring->rx_buffer_info;
i -= rx_ring->count;
}
/* clear the length for the next_to_use descriptor */
rx_desc->wb.upper.length = 0;
cleaned_count--;
} while (cleaned_count);
i += rx_ring->count;
if (rx_ring->next_to_use != i) {
rx_ring->next_to_use = i;
/* update next to alloc since we have filled the ring */
rx_ring->next_to_alloc = i;
/* Force memory writes to complete before letting h/w
* know there are new descriptors to fetch. (Only
* applicable for weak-ordered memory model archs,
* such as IA-64).
*/
wmb();
writel(i, rx_ring->tail);
}
return ok;
}
void ixgbe_alloc_rx_buffers_zc(struct ixgbe_ring *rx_ring, u16 count)
{
__ixgbe_alloc_rx_buffers_zc(rx_ring, count,
ixgbe_alloc_buffer_slow_zc);
}
static bool ixgbe_alloc_rx_buffers_fast_zc(struct ixgbe_ring *rx_ring,
u16 count)
{
return __ixgbe_alloc_rx_buffers_zc(rx_ring, count,
ixgbe_alloc_buffer_zc);
}
static struct sk_buff *ixgbe_construct_skb_zc(struct ixgbe_ring *rx_ring,
struct ixgbe_rx_buffer *bi,
struct xdp_buff *xdp)
{
unsigned int metasize = xdp->data - xdp->data_meta;
unsigned int datasize = xdp->data_end - xdp->data;
struct sk_buff *skb;
/* allocate a skb to store the frags */
skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
xdp->data_end - xdp->data_hard_start,
GFP_ATOMIC | __GFP_NOWARN);
if (unlikely(!skb))
return NULL;
skb_reserve(skb, xdp->data - xdp->data_hard_start);
memcpy(__skb_put(skb, datasize), xdp->data, datasize);
if (metasize)
skb_metadata_set(skb, metasize);
ixgbe_reuse_rx_buffer_zc(rx_ring, bi);
return skb;
}
static void ixgbe_inc_ntc(struct ixgbe_ring *rx_ring)
{
u32 ntc = rx_ring->next_to_clean + 1;
ntc = (ntc < rx_ring->count) ? ntc : 0;
rx_ring->next_to_clean = ntc;
prefetch(IXGBE_RX_DESC(rx_ring, ntc));
}
int ixgbe_clean_rx_irq_zc(struct ixgbe_q_vector *q_vector,
struct ixgbe_ring *rx_ring,
const int budget)
{
unsigned int total_rx_bytes = 0, total_rx_packets = 0;
struct ixgbe_adapter *adapter = q_vector->adapter;
u16 cleaned_count = ixgbe_desc_unused(rx_ring);
unsigned int xdp_res, xdp_xmit = 0;
bool failure = false;
struct sk_buff *skb;
struct xdp_buff xdp;
xdp.rxq = &rx_ring->xdp_rxq;
while (likely(total_rx_packets < budget)) {
union ixgbe_adv_rx_desc *rx_desc;
struct ixgbe_rx_buffer *bi;
unsigned int size;
/* return some buffers to hardware, one at a time is too slow */
if (cleaned_count >= IXGBE_RX_BUFFER_WRITE) {
failure = failure ||
!ixgbe_alloc_rx_buffers_fast_zc(rx_ring,
cleaned_count);
cleaned_count = 0;
}
rx_desc = IXGBE_RX_DESC(rx_ring, rx_ring->next_to_clean);
size = le16_to_cpu(rx_desc->wb.upper.length);
if (!size)
break;
/* This memory barrier is needed to keep us from reading
* any other fields out of the rx_desc until we know the
* descriptor has been written back
*/
dma_rmb();
bi = ixgbe_get_rx_buffer_zc(rx_ring, size);
if (unlikely(!ixgbe_test_staterr(rx_desc,
IXGBE_RXD_STAT_EOP))) {
struct ixgbe_rx_buffer *next_bi;
ixgbe_reuse_rx_buffer_zc(rx_ring, bi);
ixgbe_inc_ntc(rx_ring);
next_bi =
&rx_ring->rx_buffer_info[rx_ring->next_to_clean];
next_bi->skb = ERR_PTR(-EINVAL);
continue;
}
if (unlikely(bi->skb)) {
ixgbe_reuse_rx_buffer_zc(rx_ring, bi);
ixgbe_inc_ntc(rx_ring);
continue;
}
xdp.data = bi->addr;
xdp.data_meta = xdp.data;
xdp.data_hard_start = xdp.data - XDP_PACKET_HEADROOM;
xdp.data_end = xdp.data + size;
xdp.handle = bi->handle;
xdp_res = ixgbe_run_xdp_zc(adapter, rx_ring, &xdp);
if (xdp_res) {
if (xdp_res & (IXGBE_XDP_TX | IXGBE_XDP_REDIR)) {
xdp_xmit |= xdp_res;
bi->addr = NULL;
bi->skb = NULL;
} else {
ixgbe_reuse_rx_buffer_zc(rx_ring, bi);
}
total_rx_packets++;
total_rx_bytes += size;
cleaned_count++;
ixgbe_inc_ntc(rx_ring);
continue;
}
/* XDP_PASS path */
skb = ixgbe_construct_skb_zc(rx_ring, bi, &xdp);
if (!skb) {
rx_ring->rx_stats.alloc_rx_buff_failed++;
break;
}
cleaned_count++;
ixgbe_inc_ntc(rx_ring);
if (eth_skb_pad(skb))
continue;
total_rx_bytes += skb->len;
total_rx_packets++;
ixgbe_process_skb_fields(rx_ring, rx_desc, skb);
ixgbe_rx_skb(q_vector, skb);
}
if (xdp_xmit & IXGBE_XDP_REDIR)
xdp_do_flush_map();
if (xdp_xmit & IXGBE_XDP_TX) {
struct ixgbe_ring *ring = adapter->xdp_ring[smp_processor_id()];
/* Force memory writes to complete before letting h/w
* know there are new descriptors to fetch.
*/
wmb();
writel(ring->next_to_use, ring->tail);
}
u64_stats_update_begin(&rx_ring->syncp);
rx_ring->stats.packets += total_rx_packets;
rx_ring->stats.bytes += total_rx_bytes;
u64_stats_update_end(&rx_ring->syncp);
q_vector->rx.total_packets += total_rx_packets;
q_vector->rx.total_bytes += total_rx_bytes;
return failure ? budget : (int)total_rx_packets;
}
void ixgbe_xsk_clean_rx_ring(struct ixgbe_ring *rx_ring)
{
u16 i = rx_ring->next_to_clean;
struct ixgbe_rx_buffer *bi = &rx_ring->rx_buffer_info[i];
while (i != rx_ring->next_to_alloc) {
xsk_umem_fq_reuse(rx_ring->xsk_umem, bi->handle);
i++;
bi++;
if (i == rx_ring->count) {
i = 0;
bi = rx_ring->rx_buffer_info;
}
}
}
static bool ixgbe_xmit_zc(struct ixgbe_ring *xdp_ring, unsigned int budget)
{
union ixgbe_adv_tx_desc *tx_desc = NULL;
struct ixgbe_tx_buffer *tx_bi;
bool work_done = true;
struct xdp_desc desc;
dma_addr_t dma;
u32 cmd_type;
while (budget-- > 0) {
if (unlikely(!ixgbe_desc_unused(xdp_ring)) ||
!netif_carrier_ok(xdp_ring->netdev)) {
work_done = false;
break;
}
if (!xsk_umem_consume_tx(xdp_ring->xsk_umem, &desc))
break;
dma = xdp_umem_get_dma(xdp_ring->xsk_umem, desc.addr);
dma_sync_single_for_device(xdp_ring->dev, dma, desc.len,
DMA_BIDIRECTIONAL);
tx_bi = &xdp_ring->tx_buffer_info[xdp_ring->next_to_use];
tx_bi->bytecount = desc.len;
tx_bi->xdpf = NULL;
tx_bi->gso_segs = 1;
tx_desc = IXGBE_TX_DESC(xdp_ring, xdp_ring->next_to_use);
tx_desc->read.buffer_addr = cpu_to_le64(dma);
/* put descriptor type bits */
cmd_type = IXGBE_ADVTXD_DTYP_DATA |
IXGBE_ADVTXD_DCMD_DEXT |
IXGBE_ADVTXD_DCMD_IFCS;
cmd_type |= desc.len | IXGBE_TXD_CMD;
tx_desc->read.cmd_type_len = cpu_to_le32(cmd_type);
tx_desc->read.olinfo_status =
cpu_to_le32(desc.len << IXGBE_ADVTXD_PAYLEN_SHIFT);
xdp_ring->next_to_use++;
if (xdp_ring->next_to_use == xdp_ring->count)
xdp_ring->next_to_use = 0;
}
if (tx_desc) {
ixgbe_xdp_ring_update_tail(xdp_ring);
xsk_umem_consume_tx_done(xdp_ring->xsk_umem);
}
return !!budget && work_done;
}
static void ixgbe_clean_xdp_tx_buffer(struct ixgbe_ring *tx_ring,
struct ixgbe_tx_buffer *tx_bi)
{
xdp_return_frame(tx_bi->xdpf);
dma_unmap_single(tx_ring->dev,
dma_unmap_addr(tx_bi, dma),
dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
dma_unmap_len_set(tx_bi, len, 0);
}
bool ixgbe_clean_xdp_tx_irq(struct ixgbe_q_vector *q_vector,
struct ixgbe_ring *tx_ring, int napi_budget)
{
unsigned int total_packets = 0, total_bytes = 0;
u32 i = tx_ring->next_to_clean, xsk_frames = 0;
unsigned int budget = q_vector->tx.work_limit;
struct xdp_umem *umem = tx_ring->xsk_umem;
union ixgbe_adv_tx_desc *tx_desc;
struct ixgbe_tx_buffer *tx_bi;
bool xmit_done;
tx_bi = &tx_ring->tx_buffer_info[i];
tx_desc = IXGBE_TX_DESC(tx_ring, i);
i -= tx_ring->count;
do {
if (!(tx_desc->wb.status & cpu_to_le32(IXGBE_TXD_STAT_DD)))
break;
total_bytes += tx_bi->bytecount;
total_packets += tx_bi->gso_segs;
if (tx_bi->xdpf)
ixgbe_clean_xdp_tx_buffer(tx_ring, tx_bi);
else
xsk_frames++;
tx_bi->xdpf = NULL;
tx_bi++;
tx_desc++;
i++;
if (unlikely(!i)) {
i -= tx_ring->count;
tx_bi = tx_ring->tx_buffer_info;
tx_desc = IXGBE_TX_DESC(tx_ring, 0);
}
/* issue prefetch for next Tx descriptor */
prefetch(tx_desc);
/* update budget accounting */
budget--;
} while (likely(budget));
i += tx_ring->count;
tx_ring->next_to_clean = i;
u64_stats_update_begin(&tx_ring->syncp);
tx_ring->stats.bytes += total_bytes;
tx_ring->stats.packets += total_packets;
u64_stats_update_end(&tx_ring->syncp);
q_vector->tx.total_bytes += total_bytes;
q_vector->tx.total_packets += total_packets;
if (xsk_frames)
xsk_umem_complete_tx(umem, xsk_frames);
xmit_done = ixgbe_xmit_zc(tx_ring, q_vector->tx.work_limit);
return budget > 0 && xmit_done;
}
int ixgbe_xsk_wakeup(struct net_device *dev, u32 qid, u32 flags)
{
struct ixgbe_adapter *adapter = netdev_priv(dev);
struct ixgbe_ring *ring;
if (test_bit(__IXGBE_DOWN, &adapter->state))
return -ENETDOWN;
if (!READ_ONCE(adapter->xdp_prog))
return -ENXIO;
if (qid >= adapter->num_xdp_queues)
return -ENXIO;
if (!adapter->xdp_ring[qid]->xsk_umem)
return -ENXIO;
ring = adapter->xdp_ring[qid];
if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi)) {
u64 eics = BIT_ULL(ring->q_vector->v_idx);
ixgbe_irq_rearm_queues(adapter, eics);
}
return 0;
}
void ixgbe_xsk_clean_tx_ring(struct ixgbe_ring *tx_ring)
{
u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
struct xdp_umem *umem = tx_ring->xsk_umem;
struct ixgbe_tx_buffer *tx_bi;
u32 xsk_frames = 0;
while (ntc != ntu) {
tx_bi = &tx_ring->tx_buffer_info[ntc];
if (tx_bi->xdpf)
ixgbe_clean_xdp_tx_buffer(tx_ring, tx_bi);
else
xsk_frames++;
tx_bi->xdpf = NULL;
ntc++;
if (ntc == tx_ring->count)
ntc = 0;
}
if (xsk_frames)
xsk_umem_complete_tx(umem, xsk_frames);
}