Commit 0a714186 authored by Björn Töpel's avatar Björn Töpel Committed by Alexei Starovoitov

i40e: add AF_XDP zero-copy Rx support

This patch adds zero-copy Rx support for AF_XDP sockets. Instead of
allocating buffers of type MEM_TYPE_PAGE_SHARED, the Rx frames are
allocated as MEM_TYPE_ZERO_COPY when AF_XDP is enabled for a certain
queue.

All AF_XDP specific functions are added to a new file, i40e_xsk.c.

Note that when AF_XDP zero-copy is enabled, the XDP action XDP_PASS
will allocate a new buffer and copy the zero-copy frame prior passing
it to the kernel stack.
Signed-off-by: default avatarBjörn Töpel <bjorn.topel@intel.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 20a739db
...@@ -22,6 +22,7 @@ i40e-objs := i40e_main.o \ ...@@ -22,6 +22,7 @@ i40e-objs := i40e_main.o \
i40e_txrx.o \ i40e_txrx.o \
i40e_ptp.o \ i40e_ptp.o \
i40e_client.o \ i40e_client.o \
i40e_virtchnl_pf.o i40e_virtchnl_pf.o \
i40e_xsk.o
i40e-$(CONFIG_I40E_DCB) += i40e_dcb.o i40e_dcb_nl.o i40e-$(CONFIG_I40E_DCB) += i40e_dcb.o i40e_dcb_nl.o
...@@ -786,6 +786,11 @@ struct i40e_vsi { ...@@ -786,6 +786,11 @@ struct i40e_vsi {
/* VSI specific handlers */ /* VSI specific handlers */
irqreturn_t (*irq_handler)(int irq, void *data); irqreturn_t (*irq_handler)(int irq, void *data);
/* AF_XDP zero-copy */
struct xdp_umem **xsk_umems;
u16 num_xsk_umems_used;
u16 num_xsk_umems;
} ____cacheline_internodealigned_in_smp; } ____cacheline_internodealigned_in_smp;
struct i40e_netdev_priv { struct i40e_netdev_priv {
...@@ -1090,6 +1095,20 @@ static inline bool i40e_enabled_xdp_vsi(struct i40e_vsi *vsi) ...@@ -1090,6 +1095,20 @@ static inline bool i40e_enabled_xdp_vsi(struct i40e_vsi *vsi)
return !!vsi->xdp_prog; return !!vsi->xdp_prog;
} }
static inline struct xdp_umem *i40e_xsk_umem(struct i40e_ring *ring)
{
bool xdp_on = i40e_enabled_xdp_vsi(ring->vsi);
int qid = ring->queue_index;
if (ring_is_xdp(ring))
qid -= ring->vsi->alloc_queue_pairs;
if (!ring->vsi->xsk_umems || !ring->vsi->xsk_umems[qid] || !xdp_on)
return NULL;
return ring->vsi->xsk_umems[qid];
}
int i40e_create_queue_channel(struct i40e_vsi *vsi, struct i40e_channel *ch); int i40e_create_queue_channel(struct i40e_vsi *vsi, struct i40e_channel *ch);
int i40e_set_bw_limit(struct i40e_vsi *vsi, u16 seid, u64 max_tx_rate); int i40e_set_bw_limit(struct i40e_vsi *vsi, u16 seid, u64 max_tx_rate);
int i40e_add_del_cloud_filter(struct i40e_vsi *vsi, int i40e_add_del_cloud_filter(struct i40e_vsi *vsi,
......
...@@ -9,7 +9,9 @@ ...@@ -9,7 +9,9 @@
/* Local includes */ /* Local includes */
#include "i40e.h" #include "i40e.h"
#include "i40e_diag.h" #include "i40e_diag.h"
#include "i40e_xsk.h"
#include <net/udp_tunnel.h> #include <net/udp_tunnel.h>
#include <net/xdp_sock.h>
/* All i40e tracepoints are defined by the include below, which /* All i40e tracepoints are defined by the include below, which
* must be included exactly once across the whole kernel with * must be included exactly once across the whole kernel with
* CREATE_TRACE_POINTS defined * CREATE_TRACE_POINTS defined
...@@ -3181,13 +3183,46 @@ static int i40e_configure_rx_ring(struct i40e_ring *ring) ...@@ -3181,13 +3183,46 @@ static int i40e_configure_rx_ring(struct i40e_ring *ring)
struct i40e_hw *hw = &vsi->back->hw; struct i40e_hw *hw = &vsi->back->hw;
struct i40e_hmc_obj_rxq rx_ctx; struct i40e_hmc_obj_rxq rx_ctx;
i40e_status err = 0; i40e_status err = 0;
bool ok;
int ret;
bitmap_zero(ring->state, __I40E_RING_STATE_NBITS); bitmap_zero(ring->state, __I40E_RING_STATE_NBITS);
/* clear the context structure first */ /* clear the context structure first */
memset(&rx_ctx, 0, sizeof(rx_ctx)); memset(&rx_ctx, 0, sizeof(rx_ctx));
if (ring->vsi->type == I40E_VSI_MAIN)
xdp_rxq_info_unreg_mem_model(&ring->xdp_rxq);
ring->xsk_umem = i40e_xsk_umem(ring);
if (ring->xsk_umem) {
ring->rx_buf_len = ring->xsk_umem->chunk_size_nohr -
XDP_PACKET_HEADROOM;
/* For AF_XDP ZC, we disallow packets to span on
* multiple buffers, thus letting us skip that
* handling in the fast-path.
*/
chain_len = 1;
ring->zca.free = i40e_zca_free;
ret = xdp_rxq_info_reg_mem_model(&ring->xdp_rxq,
MEM_TYPE_ZERO_COPY,
&ring->zca);
if (ret)
return ret;
dev_info(&vsi->back->pdev->dev,
"Registered XDP mem model MEM_TYPE_ZERO_COPY on Rx ring %d\n",
ring->queue_index);
} else {
ring->rx_buf_len = vsi->rx_buf_len; ring->rx_buf_len = vsi->rx_buf_len;
if (ring->vsi->type == I40E_VSI_MAIN) {
ret = xdp_rxq_info_reg_mem_model(&ring->xdp_rxq,
MEM_TYPE_PAGE_SHARED,
NULL);
if (ret)
return ret;
}
}
rx_ctx.dbuff = DIV_ROUND_UP(ring->rx_buf_len, rx_ctx.dbuff = DIV_ROUND_UP(ring->rx_buf_len,
BIT_ULL(I40E_RXQ_CTX_DBUFF_SHIFT)); BIT_ULL(I40E_RXQ_CTX_DBUFF_SHIFT));
...@@ -3243,7 +3278,15 @@ static int i40e_configure_rx_ring(struct i40e_ring *ring) ...@@ -3243,7 +3278,15 @@ static int i40e_configure_rx_ring(struct i40e_ring *ring)
ring->tail = hw->hw_addr + I40E_QRX_TAIL(pf_q); ring->tail = hw->hw_addr + I40E_QRX_TAIL(pf_q);
writel(0, ring->tail); writel(0, ring->tail);
i40e_alloc_rx_buffers(ring, I40E_DESC_UNUSED(ring)); ok = ring->xsk_umem ?
i40e_alloc_rx_buffers_zc(ring, I40E_DESC_UNUSED(ring)) :
!i40e_alloc_rx_buffers(ring, I40E_DESC_UNUSED(ring));
if (!ok) {
dev_info(&vsi->back->pdev->dev,
"Failed allocate some buffers on %sRx ring %d (pf_q %d)\n",
ring->xsk_umem ? "UMEM enabled " : "",
ring->queue_index, pf_q);
}
return 0; return 0;
} }
...@@ -12097,6 +12140,12 @@ static int i40e_xdp(struct net_device *dev, ...@@ -12097,6 +12140,12 @@ static int i40e_xdp(struct net_device *dev,
case XDP_QUERY_PROG: case XDP_QUERY_PROG:
xdp->prog_id = vsi->xdp_prog ? vsi->xdp_prog->aux->id : 0; xdp->prog_id = vsi->xdp_prog ? vsi->xdp_prog->aux->id : 0;
return 0; return 0;
case XDP_QUERY_XSK_UMEM:
return i40e_xsk_umem_query(vsi, &xdp->xsk.umem,
xdp->xsk.queue_id);
case XDP_SETUP_XSK_UMEM:
return i40e_xsk_umem_setup(vsi, xdp->xsk.umem,
xdp->xsk.queue_id);
default: default:
return -EINVAL; return -EINVAL;
} }
......
...@@ -9,6 +9,7 @@ ...@@ -9,6 +9,7 @@
#include "i40e_trace.h" #include "i40e_trace.h"
#include "i40e_prototype.h" #include "i40e_prototype.h"
#include "i40e_txrx_common.h" #include "i40e_txrx_common.h"
#include "i40e_xsk.h"
static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size, static inline __le64 build_ctob(u32 td_cmd, u32 td_offset, unsigned int size,
u32 td_tag) u32 td_tag)
...@@ -1380,6 +1381,9 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring) ...@@ -1380,6 +1381,9 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
rx_ring->skb = NULL; rx_ring->skb = NULL;
} }
if (rx_ring->xsk_umem)
goto skip_free;
/* Free all the Rx ring sk_buffs */ /* Free all the Rx ring sk_buffs */
for (i = 0; i < rx_ring->count; i++) { for (i = 0; i < rx_ring->count; i++) {
struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i]; struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
...@@ -1408,6 +1412,7 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring) ...@@ -1408,6 +1412,7 @@ void i40e_clean_rx_ring(struct i40e_ring *rx_ring)
rx_bi->page_offset = 0; rx_bi->page_offset = 0;
} }
skip_free:
bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count; bi_size = sizeof(struct i40e_rx_buffer) * rx_ring->count;
memset(rx_ring->rx_bi, 0, bi_size); memset(rx_ring->rx_bi, 0, bi_size);
...@@ -2641,7 +2646,9 @@ int i40e_napi_poll(struct napi_struct *napi, int budget) ...@@ -2641,7 +2646,9 @@ int i40e_napi_poll(struct napi_struct *napi, int budget)
budget_per_ring = max(budget/q_vector->num_ringpairs, 1); budget_per_ring = max(budget/q_vector->num_ringpairs, 1);
i40e_for_each_ring(ring, q_vector->rx) { i40e_for_each_ring(ring, q_vector->rx) {
int cleaned = i40e_clean_rx_irq(ring, budget_per_ring); int cleaned = ring->xsk_umem ?
i40e_clean_rx_irq_zc(ring, budget_per_ring) :
i40e_clean_rx_irq(ring, budget_per_ring);
work_done += cleaned; work_done += cleaned;
/* if we clean as many as budgeted, we must not be done */ /* if we clean as many as budgeted, we must not be done */
......
...@@ -296,13 +296,17 @@ struct i40e_tx_buffer { ...@@ -296,13 +296,17 @@ struct i40e_tx_buffer {
struct i40e_rx_buffer { struct i40e_rx_buffer {
dma_addr_t dma; dma_addr_t dma;
union {
struct {
struct page *page; struct page *page;
#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
__u32 page_offset; __u32 page_offset;
#else
__u16 page_offset;
#endif
__u16 pagecnt_bias; __u16 pagecnt_bias;
};
struct {
void *addr;
u64 handle;
};
};
}; };
struct i40e_queue_stats { struct i40e_queue_stats {
...@@ -414,6 +418,8 @@ struct i40e_ring { ...@@ -414,6 +418,8 @@ struct i40e_ring {
struct i40e_channel *ch; struct i40e_channel *ch;
struct xdp_rxq_info xdp_rxq; struct xdp_rxq_info xdp_rxq;
struct xdp_umem *xsk_umem;
struct zero_copy_allocator zca; /* ZC allocator anchor */
} ____cacheline_internodealigned_in_smp; } ____cacheline_internodealigned_in_smp;
static inline bool ring_uses_build_skb(struct i40e_ring *ring) static inline bool ring_uses_build_skb(struct i40e_ring *ring)
......
// 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_alloc_xsk_umems - Allocate an array to store per ring UMEMs
* @vsi: Current VSI
*
* Returns 0 on success, <0 on failure
**/
static int i40e_alloc_xsk_umems(struct i40e_vsi *vsi)
{
if (vsi->xsk_umems)
return 0;
vsi->num_xsk_umems_used = 0;
vsi->num_xsk_umems = vsi->alloc_queue_pairs;
vsi->xsk_umems = kcalloc(vsi->num_xsk_umems, sizeof(*vsi->xsk_umems),
GFP_KERNEL);
if (!vsi->xsk_umems) {
vsi->num_xsk_umems = 0;
return -ENOMEM;
}
return 0;
}
/**
* i40e_add_xsk_umem - Store an UMEM for a certain ring/qid
* @vsi: Current VSI
* @umem: UMEM to store
* @qid: Ring/qid to associate with the UMEM
*
* Returns 0 on success, <0 on failure
**/
static int i40e_add_xsk_umem(struct i40e_vsi *vsi, struct xdp_umem *umem,
u16 qid)
{
int err;
err = i40e_alloc_xsk_umems(vsi);
if (err)
return err;
vsi->xsk_umems[qid] = umem;
vsi->num_xsk_umems_used++;
return 0;
}
/**
* i40e_remove_xsk_umem - Remove an UMEM for a certain ring/qid
* @vsi: Current VSI
* @qid: Ring/qid associated with the UMEM
**/
static void i40e_remove_xsk_umem(struct i40e_vsi *vsi, u16 qid)
{
vsi->xsk_umems[qid] = NULL;
vsi->num_xsk_umems_used--;
if (vsi->num_xsk_umems == 0) {
kfree(vsi->xsk_umems);
vsi->xsk_umems = NULL;
vsi->num_xsk_umems = 0;
}
}
/**
* 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 an 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)
{
bool if_running;
int err;
if (vsi->type != I40E_VSI_MAIN)
return -EINVAL;
if (qid >= vsi->num_queue_pairs)
return -EINVAL;
if (vsi->xsk_umems) {
if (qid >= vsi->num_xsk_umems)
return -EINVAL;
if (vsi->xsk_umems[qid])
return -EBUSY;
}
err = i40e_xsk_umem_dma_map(vsi, umem);
if (err)
return err;
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_add_xsk_umem(vsi, umem, qid);
if (err)
return err;
if (if_running) {
err = i40e_queue_pair_enable(vsi, qid);
if (err)
return err;
}
return 0;
}
/**
* i40e_xsk_umem_disable - Diassociate an 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)
{
bool if_running;
int err;
if (!vsi->xsk_umems || qid >= vsi->num_xsk_umems ||
!vsi->xsk_umems[qid])
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;
}
i40e_xsk_umem_dma_unmap(vsi, vsi->xsk_umems[qid]);
i40e_remove_xsk_umem(vsi, qid);
if (if_running) {
err = i40e_queue_pair_enable(vsi, qid);
if (err)
return err;
}
return 0;
}
/**
* i40e_xsk_umem_query - Queries a certain ring/qid for its UMEM
* @vsi: Current VSI
* @umem: UMEM associated to the ring, if any
* @qid: Rx ring to associate UMEM to
*
* This function will store, if any, the UMEM associated to certain ring.
*
* Returns 0 on success, <0 on failure
**/
int i40e_xsk_umem_query(struct i40e_vsi *vsi, struct xdp_umem **umem,
u16 qid)
{
if (vsi->type != I40E_VSI_MAIN)
return -EINVAL;
if (qid >= vsi->num_queue_pairs)
return -EINVAL;
if (vsi->xsk_umems) {
if (qid >= vsi->num_xsk_umems)
return -EINVAL;
*umem = vsi->xsk_umems[qid];
return 0;
}
*umem = NULL;
return 0;
}
/**
* i40e_xsk_umem_query - Queries a certain ring/qid for its UMEM
* @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 an 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 an 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)
{
int err, result = I40E_XDP_PASS;
struct i40e_ring *xdp_ring;
struct bpf_prog *xdp_prog;
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);
xdp->handle += xdp->data - xdp->data_hard_start;
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);
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 = handle + umem->headroom;
xsk_umem_discard_addr(umem);
return true;
}
/**
* 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 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)
{
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 (!i40e_alloc_buffer_zc(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_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];
unsigned long mask = (unsigned long)rx_ring->xsk_umem->props.chunk_mask;
u64 hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
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 & mask;
new_bi->dma += hr;
new_bi->addr = (void *)((unsigned long)old_bi->addr & mask);
new_bi->addr += hr;
new_bi->handle = old_bi->handle & mask;
new_bi->handle += rx_ring->xsk_umem->headroom;
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->props.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 = (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;
u16 vlan_tag;
u8 rx_ptype;
u64 qword;
if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
failure = failure ||
!i40e_alloc_rx_buffers_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++;
qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
rx_ptype = (qword & I40E_RXD_QW1_PTYPE_MASK) >>
I40E_RXD_QW1_PTYPE_SHIFT;
i40e_process_skb_fields(rx_ring, rx_desc, skb, rx_ptype);
vlan_tag = (qword & BIT(I40E_RX_DESC_STATUS_L2TAG1P_SHIFT)) ?
le16_to_cpu(rx_desc->wb.qword0.lo_dword.l2tag1) : 0;
i40e_receive_skb(rx_ring, skb, vlan_tag);
}
i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
return failure ? budget : (int)total_rx_packets;
}
/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright(c) 2018 Intel Corporation. */
#ifndef _I40E_XSK_H_
#define _I40E_XSK_H_
struct i40e_vsi;
struct xdp_umem;
struct zero_copy_allocator;
int i40e_queue_pair_disable(struct i40e_vsi *vsi, int queue_pair);
int i40e_queue_pair_enable(struct i40e_vsi *vsi, int queue_pair);
int i40e_xsk_umem_query(struct i40e_vsi *vsi, struct xdp_umem **umem,
u16 qid);
int i40e_xsk_umem_setup(struct i40e_vsi *vsi, struct xdp_umem *umem,
u16 qid);
void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle);
bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 cleaned_count);
int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget);
#endif /* _I40E_XSK_H_ */
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