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// 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 "i40e.h"
#include "i40e_txrx_common.h"
#include "i40e_xsk.h"
/**
* i40e_xsk_umem_dma_map - DMA maps all UMEM memory for the netdev
* @vsi: Current VSI
* @umem: UMEM to DMA map
*
* Returns 0 on success, <0 on failure
**/
static int i40e_xsk_umem_dma_map(struct i40e_vsi *vsi, struct xdp_umem *umem)
{
struct i40e_pf *pf = vsi->back;
struct device *dev;
unsigned int i, j;
dma_addr_t dma;
dev = &pf->pdev->dev;
for (i = 0; i < umem->npgs; i++) {
dma = dma_map_page_attrs(dev, umem->pgs[i], 0, PAGE_SIZE,
DMA_BIDIRECTIONAL, I40E_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, I40E_RX_DMA_ATTR);
umem->pages[i].dma = 0;
}
return -1;
}
/**
* i40e_xsk_umem_dma_unmap - DMA unmaps all UMEM memory for the netdev
* @vsi: Current VSI
* @umem: UMEM to DMA map
**/
static void i40e_xsk_umem_dma_unmap(struct i40e_vsi *vsi, struct xdp_umem *umem)
{
struct i40e_pf *pf = vsi->back;
struct device *dev;
unsigned int i;
dev = &pf->pdev->dev;
for (i = 0; i < umem->npgs; i++) {
dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
umem->pages[i].dma = 0;
}
}
/**
* i40e_xsk_umem_enable - Enable/associate a UMEM to a certain ring/qid
* @vsi: Current VSI
* @umem: UMEM
* @qid: Rx ring to associate UMEM to
*
* Returns 0 on success, <0 on failure
**/
static int i40e_xsk_umem_enable(struct i40e_vsi *vsi, struct xdp_umem *umem,
u16 qid)
{
struct net_device *netdev = vsi->netdev;
struct xdp_umem_fq_reuse *reuseq;
bool if_running;
int err;
if (vsi->type != I40E_VSI_MAIN)
return -EINVAL;
if (qid >= vsi->num_queue_pairs)
return -EINVAL;
if (qid >= netdev->real_num_rx_queues ||
qid >= netdev->real_num_tx_queues)
return -EINVAL;
reuseq = xsk_reuseq_prepare(vsi->rx_rings[0]->count);
if (!reuseq)
return -ENOMEM;
xsk_reuseq_free(xsk_reuseq_swap(umem, reuseq));
err = i40e_xsk_umem_dma_map(vsi, umem);
if (err)
return err;
set_bit(qid, vsi->af_xdp_zc_qps);
if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
if (if_running) {
err = i40e_queue_pair_disable(vsi, qid);
if (err)
return err;
err = i40e_queue_pair_enable(vsi, qid);
if (err)
return err;
/* Kick start the NAPI context so that receiving will start */
err = i40e_xsk_wakeup(vsi->netdev, qid, XDP_WAKEUP_RX);
if (err)
return err;
}
return 0;
}
/**
* i40e_xsk_umem_disable - Disassociate a UMEM from a certain ring/qid
* @vsi: Current VSI
* @qid: Rx ring to associate UMEM to
*
* Returns 0 on success, <0 on failure
**/
static int i40e_xsk_umem_disable(struct i40e_vsi *vsi, u16 qid)
{
struct net_device *netdev = vsi->netdev;
struct xdp_umem *umem;
bool if_running;
int err;
umem = xdp_get_umem_from_qid(netdev, qid);
if (!umem)
return -EINVAL;
if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
if (if_running) {
err = i40e_queue_pair_disable(vsi, qid);
if (err)
return err;
}
clear_bit(qid, vsi->af_xdp_zc_qps);
i40e_xsk_umem_dma_unmap(vsi, umem);
if (if_running) {
err = i40e_queue_pair_enable(vsi, qid);
if (err)
return err;
}
return 0;
}
/**
* i40e_xsk_umem_setup - Enable/disassociate a UMEM to/from a ring/qid
* @vsi: Current VSI
* @umem: UMEM to enable/associate to a ring, or NULL to disable
* @qid: Rx ring to (dis)associate UMEM (from)to
*
* This function enables or disables a UMEM to a certain ring.
*
* Returns 0 on success, <0 on failure
**/
int i40e_xsk_umem_setup(struct i40e_vsi *vsi, struct xdp_umem *umem,
u16 qid)
{
return umem ? i40e_xsk_umem_enable(vsi, umem, qid) :
i40e_xsk_umem_disable(vsi, qid);
}
/**
* i40e_run_xdp_zc - Executes an XDP program on an xdp_buff
* @rx_ring: Rx ring
* @xdp: xdp_buff used as input to the XDP program
*
* This function enables or disables a UMEM to a certain ring.
*
* Returns any of I40E_XDP_{PASS, CONSUMED, TX, REDIR}
**/
static int i40e_run_xdp_zc(struct i40e_ring *rx_ring, struct xdp_buff *xdp)
{
struct xdp_umem *umem = rx_ring->xsk_umem;
int err, result = I40E_XDP_PASS;
struct i40e_ring *xdp_ring;
struct bpf_prog *xdp_prog;
u64 offset;
u32 act;
rcu_read_lock();
/* NB! xdp_prog will always be !NULL, due to the fact that
* this path is enabled by setting an XDP program.
*/
xdp_prog = READ_ONCE(rx_ring->xdp_prog);
act = bpf_prog_run_xdp(xdp_prog, xdp);
offset = xdp->data - xdp->data_hard_start;
xdp->handle = xsk_umem_adjust_offset(umem, xdp->handle, offset);
switch (act) {
case XDP_PASS:
break;
case XDP_TX:
xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
break;
case XDP_REDIRECT:
err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
result = !err ? I40E_XDP_REDIR : I40E_XDP_CONSUMED;
break;
default:
bpf_warn_invalid_xdp_action(act);
/* fall through */
case XDP_ABORTED:
trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
/* fallthrough -- handle aborts by dropping packet */
case XDP_DROP:
result = I40E_XDP_CONSUMED;
break;
}
rcu_read_unlock();
return result;
}
/**
* i40e_alloc_buffer_zc - Allocates an i40e_rx_buffer
* @rx_ring: Rx ring
* @bi: Rx buffer to populate
*
* This function allocates an Rx buffer. The buffer can come from fill
* queue, or via the recycle queue (next_to_alloc).
*
* Returns true for a successful allocation, false otherwise
**/
static bool i40e_alloc_buffer_zc(struct i40e_ring *rx_ring,
struct i40e_rx_buffer *bi)
{
struct xdp_umem *umem = rx_ring->xsk_umem;
void *addr = bi->addr;
u64 handle, hr;
if (addr) {
rx_ring->rx_stats.page_reuse_count++;
return true;
}
if (!xsk_umem_peek_addr(umem, &handle)) {
rx_ring->rx_stats.alloc_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 = xsk_umem_adjust_offset(umem, handle, umem->headroom);
xsk_umem_discard_addr(umem);
return true;
}
/**
* i40e_alloc_buffer_slow_zc - Allocates an i40e_rx_buffer
* @rx_ring: Rx ring
* @bi: Rx buffer to populate
*
* This function allocates an Rx buffer. The buffer can come from fill
* queue, or via the reuse queue.
*
* Returns true for a successful allocation, false otherwise
**/
static bool i40e_alloc_buffer_slow_zc(struct i40e_ring *rx_ring,
struct i40e_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_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 = xsk_umem_adjust_offset(umem, handle, umem->headroom);
xsk_umem_discard_addr_rq(umem);
return true;
}
static __always_inline bool
__i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count,
bool alloc(struct i40e_ring *rx_ring,
struct i40e_rx_buffer *bi))
{
u16 ntu = rx_ring->next_to_use;
union i40e_rx_desc *rx_desc;
struct i40e_rx_buffer *bi;
bool ok = true;
rx_desc = I40E_RX_DESC(rx_ring, ntu);
bi = &rx_ring->rx_bi[ntu];
do {
if (!alloc(rx_ring, bi)) {
ok = false;
goto no_buffers;
}
dma_sync_single_range_for_device(rx_ring->dev, bi->dma, 0,
rx_ring->rx_buf_len,
DMA_BIDIRECTIONAL);
rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
rx_desc++;
bi++;
ntu++;
if (unlikely(ntu == rx_ring->count)) {
rx_desc = I40E_RX_DESC(rx_ring, 0);
bi = rx_ring->rx_bi;
ntu = 0;
}
rx_desc->wb.qword1.status_error_len = 0;
count--;
} while (count);
no_buffers:
if (rx_ring->next_to_use != ntu)
i40e_release_rx_desc(rx_ring, ntu);
return ok;
}
/**
* i40e_alloc_rx_buffers_zc - Allocates a number of Rx buffers
* @rx_ring: Rx ring
* @count: The number of buffers to allocate
*
* This function allocates a number of Rx buffers from the reuse queue
* or fill ring and places them on the Rx ring.
*
* Returns true for a successful allocation, false otherwise
**/
bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
{
return __i40e_alloc_rx_buffers_zc(rx_ring, count,
i40e_alloc_buffer_slow_zc);
}
/**
* i40e_alloc_rx_buffers_fast_zc - Allocates a number of Rx buffers
* @rx_ring: Rx ring
* @count: The number of buffers to allocate
*
* This function allocates a number of Rx buffers from the fill ring
* or the internal recycle mechanism and places them on the Rx ring.
*
* Returns true for a successful allocation, false otherwise
**/
static bool i40e_alloc_rx_buffers_fast_zc(struct i40e_ring *rx_ring, u16 count)
{
return __i40e_alloc_rx_buffers_zc(rx_ring, count,
i40e_alloc_buffer_zc);
}
/**
* i40e_get_rx_buffer_zc - Return the current Rx buffer
* @rx_ring: Rx ring
* @size: The size of the rx buffer (read from descriptor)
*
* This function returns the current, received Rx buffer, and also
* does DMA synchronization. the Rx ring.
*
* Returns the received Rx buffer
**/
static struct i40e_rx_buffer *i40e_get_rx_buffer_zc(struct i40e_ring *rx_ring,
const unsigned int size)
{
struct i40e_rx_buffer *bi;
bi = &rx_ring->rx_bi[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;
}
/**
* i40e_reuse_rx_buffer_zc - Recycle an Rx buffer
* @rx_ring: Rx ring
* @old_bi: The Rx buffer to recycle
*
* This function recycles a finished Rx buffer, and places it on the
* recycle queue (next_to_alloc).
**/
static void i40e_reuse_rx_buffer_zc(struct i40e_ring *rx_ring,
struct i40e_rx_buffer *old_bi)
{
struct i40e_rx_buffer *new_bi = &rx_ring->rx_bi[rx_ring->next_to_alloc];
u16 nta = 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 */
new_bi->dma = old_bi->dma;
new_bi->addr = old_bi->addr;
new_bi->handle = old_bi->handle;
old_bi->addr = NULL;
}
/**
* i40e_zca_free - Free callback for MEM_TYPE_ZERO_COPY allocations
* @alloc: Zero-copy allocator
* @handle: Buffer handle
**/
void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle)
{
struct i40e_rx_buffer *bi;
struct i40e_ring *rx_ring;
u64 hr, mask;
u16 nta;
rx_ring = container_of(alloc, struct i40e_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_bi[nta];
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 = xsk_umem_adjust_offset(rx_ring->xsk_umem, (u64)handle,
rx_ring->xsk_umem->headroom);
}
/**
* i40e_construct_skb_zc - Create skbufff from zero-copy Rx buffer
* @rx_ring: Rx ring
* @bi: Rx buffer
* @xdp: xdp_buff
*
* This functions allocates a new skb from a zero-copy Rx buffer.
*
* Returns the skb, or NULL on failure.
**/
static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring,
struct i40e_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);
i40e_reuse_rx_buffer_zc(rx_ring, bi);
return skb;
}
/**
* i40e_inc_ntc: Advance the next_to_clean index
* @rx_ring: Rx ring
**/
static void i40e_inc_ntc(struct i40e_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(I40E_RX_DESC(rx_ring, ntc));
}
/**
* i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring
* @rx_ring: Rx ring
* @budget: NAPI budget
*
* Returns amount of work completed
**/
int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
{
unsigned int total_rx_bytes = 0, total_rx_packets = 0;
u16 cleaned_count = I40E_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 < (unsigned int)budget)) {
struct i40e_rx_buffer *bi;
union i40e_rx_desc *rx_desc;
unsigned int size;
u64 qword;
if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
failure = failure ||
!i40e_alloc_rx_buffers_fast_zc(rx_ring,
cleaned_count);
cleaned_count = 0;
}
rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
/* This memory barrier is needed to keep us from reading
* any other fields out of the rx_desc until we have
* verified the descriptor has been written back.
*/
dma_rmb();
bi = i40e_clean_programming_status(rx_ring, rx_desc,
qword);
if (unlikely(bi)) {
i40e_reuse_rx_buffer_zc(rx_ring, bi);
cleaned_count++;
continue;
}
size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
if (!size)
break;
bi = i40e_get_rx_buffer_zc(rx_ring, size);
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 = i40e_run_xdp_zc(rx_ring, &xdp);
if (xdp_res) {
if (xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR)) {
xdp_xmit |= xdp_res;
bi->addr = NULL;
} else {
i40e_reuse_rx_buffer_zc(rx_ring, bi);
}
total_rx_bytes += size;
total_rx_packets++;
cleaned_count++;
i40e_inc_ntc(rx_ring);
continue;
}
/* XDP_PASS path */
/* NB! We are not checking for errors using
* i40e_test_staterr with
* BIT(I40E_RXD_QW1_ERROR_SHIFT). This is due to that
* SBP is *not* set in PRT_SBPVSI (default not set).
*/
skb = i40e_construct_skb_zc(rx_ring, bi, &xdp);
if (!skb) {
rx_ring->rx_stats.alloc_buff_failed++;
break;
}
cleaned_count++;
i40e_inc_ntc(rx_ring);
if (eth_skb_pad(skb))
continue;
total_rx_bytes += skb->len;
total_rx_packets++;
i40e_process_skb_fields(rx_ring, rx_desc, skb);
napi_gro_receive(&rx_ring->q_vector->napi, skb);
}
i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
if (xsk_umem_uses_need_wakeup(rx_ring->xsk_umem)) {
if (failure || rx_ring->next_to_clean == rx_ring->next_to_use)
xsk_set_rx_need_wakeup(rx_ring->xsk_umem);
else
xsk_clear_rx_need_wakeup(rx_ring->xsk_umem);
return (int)total_rx_packets;
}
return failure ? budget : (int)total_rx_packets;
}
/**
* i40e_xmit_zc - Performs zero-copy Tx AF_XDP
* @xdp_ring: XDP Tx ring
* @budget: NAPI budget
*
* Returns true if the work is finished.
**/
static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
{
struct i40e_tx_desc *tx_desc = NULL;
struct i40e_tx_buffer *tx_bi;
bool work_done = true;
struct xdp_desc desc;
dma_addr_t dma;
while (budget-- > 0) {
if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
xdp_ring->tx_stats.tx_busy++;
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_bi[xdp_ring->next_to_use];
tx_bi->bytecount = desc.len;
tx_desc = I40E_TX_DESC(xdp_ring, xdp_ring->next_to_use);
tx_desc->buffer_addr = cpu_to_le64(dma);
tx_desc->cmd_type_offset_bsz =
build_ctob(I40E_TX_DESC_CMD_ICRC
| I40E_TX_DESC_CMD_EOP,
0, desc.len, 0);
xdp_ring->next_to_use++;
if (xdp_ring->next_to_use == xdp_ring->count)
xdp_ring->next_to_use = 0;
}
if (tx_desc) {
/* Request an interrupt for the last frame and bump tail ptr. */
tx_desc->cmd_type_offset_bsz |= (I40E_TX_DESC_CMD_RS <<
I40E_TXD_QW1_CMD_SHIFT);
i40e_xdp_ring_update_tail(xdp_ring);
xsk_umem_consume_tx_done(xdp_ring->xsk_umem);
}
return !!budget && work_done;
}
/**
* i40e_clean_xdp_tx_buffer - Frees and unmaps an XDP Tx entry
* @tx_ring: XDP Tx ring
* @tx_bi: Tx buffer info to clean
**/
static void i40e_clean_xdp_tx_buffer(struct i40e_ring *tx_ring,
struct i40e_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);
}
/**
* i40e_clean_xdp_tx_irq - Completes AF_XDP entries, and cleans XDP entries
* @tx_ring: XDP Tx ring
* @tx_bi: Tx buffer info to clean
*
* Returns true if cleanup/tranmission is done.
**/
bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi,
struct i40e_ring *tx_ring, int napi_budget)
{
unsigned int ntc, total_bytes = 0, budget = vsi->work_limit;
u32 i, completed_frames, frames_ready, xsk_frames = 0;
struct xdp_umem *umem = tx_ring->xsk_umem;
u32 head_idx = i40e_get_head(tx_ring);
bool work_done = true, xmit_done;
struct i40e_tx_buffer *tx_bi;
if (head_idx < tx_ring->next_to_clean)
head_idx += tx_ring->count;
frames_ready = head_idx - tx_ring->next_to_clean;
if (frames_ready == 0) {
goto out_xmit;
} else if (frames_ready > budget) {
completed_frames = budget;
work_done = false;
} else {
completed_frames = frames_ready;
}
ntc = tx_ring->next_to_clean;
for (i = 0; i < completed_frames; i++) {
tx_bi = &tx_ring->tx_bi[ntc];
if (tx_bi->xdpf)
i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
else
xsk_frames++;
tx_bi->xdpf = NULL;
total_bytes += tx_bi->bytecount;
if (++ntc >= tx_ring->count)
ntc = 0;
}
tx_ring->next_to_clean += completed_frames;
if (unlikely(tx_ring->next_to_clean >= tx_ring->count))
tx_ring->next_to_clean -= tx_ring->count;
if (xsk_frames)
xsk_umem_complete_tx(umem, xsk_frames);
i40e_arm_wb(tx_ring, vsi, budget);
i40e_update_tx_stats(tx_ring, completed_frames, total_bytes);
out_xmit:
if (xsk_umem_uses_need_wakeup(tx_ring->xsk_umem))
xsk_set_tx_need_wakeup(tx_ring->xsk_umem);
xmit_done = i40e_xmit_zc(tx_ring, budget);
return work_done && xmit_done;
}
/**
* i40e_xsk_wakeup - Implements the ndo_xsk_wakeup
* @dev: the netdevice
* @queue_id: queue id to wake up
* @flags: ignored in our case since we have Rx and Tx in the same NAPI.
*
* Returns <0 for errors, 0 otherwise.
**/
int i40e_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags)
{
struct i40e_netdev_priv *np = netdev_priv(dev);
struct i40e_vsi *vsi = np->vsi;
struct i40e_ring *ring;
if (test_bit(__I40E_VSI_DOWN, vsi->state))
return -ENETDOWN;
if (!i40e_enabled_xdp_vsi(vsi))
return -ENXIO;
if (queue_id >= vsi->num_queue_pairs)
return -ENXIO;
if (!vsi->xdp_rings[queue_id]->xsk_umem)
return -ENXIO;
ring = vsi->xdp_rings[queue_id];
/* The idea here is that if NAPI is running, mark a miss, so
* it will run again. If not, trigger an interrupt and
* schedule the NAPI from interrupt context. If NAPI would be
* scheduled here, the interrupt affinity would not be
* honored.
*/
if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi))
i40e_force_wb(vsi, ring->q_vector);
return 0;
}
void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring)
{
u16 i;
for (i = 0; i < rx_ring->count; i++) {
struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
if (!rx_bi->addr)
continue;
xsk_umem_fq_reuse(rx_ring->xsk_umem, rx_bi->handle);
rx_bi->addr = NULL;
}
}
/**
* i40e_xsk_clean_xdp_ring - Clean the XDP Tx ring on shutdown
* @xdp_ring: XDP Tx ring
**/
void i40e_xsk_clean_tx_ring(struct i40e_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 i40e_tx_buffer *tx_bi;
u32 xsk_frames = 0;
while (ntc != ntu) {
tx_bi = &tx_ring->tx_bi[ntc];
if (tx_bi->xdpf)
i40e_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);
}
/**
* i40e_xsk_any_rx_ring_enabled - Checks if Rx rings have AF_XDP UMEM attached
* @vsi: vsi
*
* Returns true if any of the Rx rings has an AF_XDP UMEM attached
**/
bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi)
{
struct net_device *netdev = vsi->netdev;
int i;
for (i = 0; i < vsi->num_queue_pairs; i++) {
if (xdp_get_umem_from_qid(netdev, i))
return true;
}
return false;
}
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