/*
* Copyright (c) 2018, Mellanox Technologies. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/bpf_trace.h>
#include <net/xdp_sock.h>
#include "en/xdp.h"
#include "en/params.h"
int mlx5e_xdp_max_mtu(struct mlx5e_params *params, struct mlx5e_xsk_param *xsk)
{
int hr = mlx5e_get_linear_rq_headroom(params, xsk);
/* Let S := SKB_DATA_ALIGN(sizeof(struct skb_shared_info)).
* The condition checked in mlx5e_rx_is_linear_skb is:
* SKB_DATA_ALIGN(sw_mtu + hard_mtu + hr) + S <= PAGE_SIZE (1)
* (Note that hw_mtu == sw_mtu + hard_mtu.)
* What is returned from this function is:
* max_mtu = PAGE_SIZE - S - hr - hard_mtu (2)
* After assigning sw_mtu := max_mtu, the left side of (1) turns to
* SKB_DATA_ALIGN(PAGE_SIZE - S) + S, which is equal to PAGE_SIZE,
* because both PAGE_SIZE and S are already aligned. Any number greater
* than max_mtu would make the left side of (1) greater than PAGE_SIZE,
* so max_mtu is the maximum MTU allowed.
*/
return MLX5E_HW2SW_MTU(params, SKB_MAX_HEAD(hr));
}
static inline bool
mlx5e_xmit_xdp_buff(struct mlx5e_xdpsq *sq, struct mlx5e_rq *rq,
struct mlx5e_dma_info *di, struct xdp_buff *xdp)
{
struct mlx5e_xdp_xmit_data xdptxd;
struct mlx5e_xdp_info xdpi;
struct xdp_frame *xdpf;
dma_addr_t dma_addr;
xdpf = convert_to_xdp_frame(xdp);
if (unlikely(!xdpf))
return false;
xdptxd.data = xdpf->data;
xdptxd.len = xdpf->len;
if (xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY) {
/* The xdp_buff was in the UMEM and was copied into a newly
* allocated page. The UMEM page was returned via the ZCA, and
* this new page has to be mapped at this point and has to be
* unmapped and returned via xdp_return_frame on completion.
*/
/* Prevent double recycling of the UMEM page. Even in case this
* function returns false, the xdp_buff shouldn't be recycled,
* as it was already done in xdp_convert_zc_to_xdp_frame.
*/
__set_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags); /* non-atomic */
xdpi.mode = MLX5E_XDP_XMIT_MODE_FRAME;
dma_addr = dma_map_single(sq->pdev, xdptxd.data, xdptxd.len,
DMA_TO_DEVICE);
if (dma_mapping_error(sq->pdev, dma_addr)) {
xdp_return_frame(xdpf);
return false;
}
xdptxd.dma_addr = dma_addr;
xdpi.frame.xdpf = xdpf;
xdpi.frame.dma_addr = dma_addr;
} else {
/* Driver assumes that convert_to_xdp_frame returns an xdp_frame
* that points to the same memory region as the original
* xdp_buff. It allows to map the memory only once and to use
* the DMA_BIDIRECTIONAL mode.
*/
xdpi.mode = MLX5E_XDP_XMIT_MODE_PAGE;
dma_addr = di->addr + (xdpf->data - (void *)xdpf);
dma_sync_single_for_device(sq->pdev, dma_addr, xdptxd.len,
DMA_TO_DEVICE);
xdptxd.dma_addr = dma_addr;
xdpi.page.rq = rq;
xdpi.page.di = *di;
}
return sq->xmit_xdp_frame(sq, &xdptxd, &xdpi, 0);
}
/* returns true if packet was consumed by xdp */
bool mlx5e_xdp_handle(struct mlx5e_rq *rq, struct mlx5e_dma_info *di,
void *va, u16 *rx_headroom, u32 *len, bool xsk)
{
struct bpf_prog *prog = READ_ONCE(rq->xdp_prog);
struct xdp_buff xdp;
u32 act;
int err;
if (!prog)
return false;
xdp.data = va + *rx_headroom;
xdp_set_data_meta_invalid(&xdp);
xdp.data_end = xdp.data + *len;
xdp.data_hard_start = va;
if (xsk)
xdp.handle = di->xsk.handle;
xdp.rxq = &rq->xdp_rxq;
act = bpf_prog_run_xdp(prog, &xdp);
if (xsk)
xdp.handle += xdp.data - xdp.data_hard_start;
switch (act) {
case XDP_PASS:
*rx_headroom = xdp.data - xdp.data_hard_start;
*len = xdp.data_end - xdp.data;
return false;
case XDP_TX:
if (unlikely(!mlx5e_xmit_xdp_buff(rq->xdpsq, rq, di, &xdp)))
goto xdp_abort;
__set_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags); /* non-atomic */
return true;
case XDP_REDIRECT:
/* When XDP enabled then page-refcnt==1 here */
err = xdp_do_redirect(rq->netdev, &xdp, prog);
if (unlikely(err))
goto xdp_abort;
__set_bit(MLX5E_RQ_FLAG_XDP_XMIT, rq->flags);
__set_bit(MLX5E_RQ_FLAG_XDP_REDIRECT, rq->flags);
if (!xsk)
mlx5e_page_dma_unmap(rq, di);
rq->stats->xdp_redirect++;
return true;
default:
bpf_warn_invalid_xdp_action(act);
/* fall through */
case XDP_ABORTED:
xdp_abort:
trace_xdp_exception(rq->netdev, prog, act);
/* fall through */
case XDP_DROP:
rq->stats->xdp_drop++;
return true;
}
}
static void mlx5e_xdp_mpwqe_session_start(struct mlx5e_xdpsq *sq)
{
struct mlx5e_xdp_mpwqe *session = &sq->mpwqe;
struct mlx5e_xdpsq_stats *stats = sq->stats;
struct mlx5_wq_cyc *wq = &sq->wq;
u8 wqebbs;
u16 pi;
mlx5e_xdpsq_fetch_wqe(sq, &session->wqe);
prefetchw(session->wqe->data);
session->ds_count = MLX5E_XDP_TX_EMPTY_DS_COUNT;
session->pkt_count = 0;
session->complete = 0;
pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);
/* The mult of MLX5_SEND_WQE_MAX_WQEBBS * MLX5_SEND_WQEBB_NUM_DS
* (16 * 4 == 64) does not fit in the 6-bit DS field of Ctrl Segment.
* We use a bound lower that MLX5_SEND_WQE_MAX_WQEBBS to let a
* full-session WQE be cache-aligned.
*/
#if L1_CACHE_BYTES < 128
#define MLX5E_XDP_MPW_MAX_WQEBBS (MLX5_SEND_WQE_MAX_WQEBBS - 1)
#else
#define MLX5E_XDP_MPW_MAX_WQEBBS (MLX5_SEND_WQE_MAX_WQEBBS - 2)
#endif
wqebbs = min_t(u16, mlx5_wq_cyc_get_contig_wqebbs(wq, pi),
MLX5E_XDP_MPW_MAX_WQEBBS);
session->max_ds_count = MLX5_SEND_WQEBB_NUM_DS * wqebbs;
mlx5e_xdp_update_inline_state(sq);
stats->mpwqe++;
}
void mlx5e_xdp_mpwqe_complete(struct mlx5e_xdpsq *sq)
{
struct mlx5_wq_cyc *wq = &sq->wq;
struct mlx5e_xdp_mpwqe *session = &sq->mpwqe;
struct mlx5_wqe_ctrl_seg *cseg = &session->wqe->ctrl;
u16 ds_count = session->ds_count;
u16 pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);
struct mlx5e_xdp_wqe_info *wi = &sq->db.wqe_info[pi];
cseg->opmod_idx_opcode =
cpu_to_be32((sq->pc << 8) | MLX5_OPCODE_ENHANCED_MPSW);
cseg->qpn_ds = cpu_to_be32((sq->sqn << 8) | ds_count);
wi->num_wqebbs = DIV_ROUND_UP(ds_count, MLX5_SEND_WQEBB_NUM_DS);
wi->num_pkts = session->pkt_count;
sq->pc += wi->num_wqebbs;
sq->doorbell_cseg = cseg;
session->wqe = NULL; /* Close session */
}
enum {
MLX5E_XDP_CHECK_OK = 1,
MLX5E_XDP_CHECK_START_MPWQE = 2,
};
static int mlx5e_xmit_xdp_frame_check_mpwqe(struct mlx5e_xdpsq *sq)
{
if (unlikely(!sq->mpwqe.wqe)) {
if (unlikely(!mlx5e_wqc_has_room_for(&sq->wq, sq->cc, sq->pc,
MLX5_SEND_WQE_MAX_WQEBBS))) {
/* SQ is full, ring doorbell */
mlx5e_xmit_xdp_doorbell(sq);
sq->stats->full++;
return -EBUSY;
}
return MLX5E_XDP_CHECK_START_MPWQE;
}
return MLX5E_XDP_CHECK_OK;
}
static bool mlx5e_xmit_xdp_frame_mpwqe(struct mlx5e_xdpsq *sq,
struct mlx5e_xdp_xmit_data *xdptxd,
struct mlx5e_xdp_info *xdpi,
int check_result)
{
struct mlx5e_xdp_mpwqe *session = &sq->mpwqe;
struct mlx5e_xdpsq_stats *stats = sq->stats;
if (unlikely(xdptxd->len > sq->hw_mtu)) {
stats->err++;
return false;
}
if (!check_result)
check_result = mlx5e_xmit_xdp_frame_check_mpwqe(sq);
if (unlikely(check_result < 0))
return false;
if (check_result == MLX5E_XDP_CHECK_START_MPWQE) {
/* Start the session when nothing can fail, so it's guaranteed
* that if there is an active session, it has at least one dseg,
* and it's safe to complete it at any time.
*/
mlx5e_xdp_mpwqe_session_start(sq);
}
mlx5e_xdp_mpwqe_add_dseg(sq, xdptxd, stats);
if (unlikely(session->complete ||
session->ds_count == session->max_ds_count))
mlx5e_xdp_mpwqe_complete(sq);
mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo, xdpi);
stats->xmit++;
return true;
}
static int mlx5e_xmit_xdp_frame_check(struct mlx5e_xdpsq *sq)
{
if (unlikely(!mlx5e_wqc_has_room_for(&sq->wq, sq->cc, sq->pc, 1))) {
/* SQ is full, ring doorbell */
mlx5e_xmit_xdp_doorbell(sq);
sq->stats->full++;
return -EBUSY;
}
return MLX5E_XDP_CHECK_OK;
}
static bool mlx5e_xmit_xdp_frame(struct mlx5e_xdpsq *sq,
struct mlx5e_xdp_xmit_data *xdptxd,
struct mlx5e_xdp_info *xdpi,
int check_result)
{
struct mlx5_wq_cyc *wq = &sq->wq;
u16 pi = mlx5_wq_cyc_ctr2ix(wq, sq->pc);
struct mlx5e_tx_wqe *wqe = mlx5_wq_cyc_get_wqe(wq, pi);
struct mlx5_wqe_ctrl_seg *cseg = &wqe->ctrl;
struct mlx5_wqe_eth_seg *eseg = &wqe->eth;
struct mlx5_wqe_data_seg *dseg = wqe->data;
dma_addr_t dma_addr = xdptxd->dma_addr;
u32 dma_len = xdptxd->len;
struct mlx5e_xdpsq_stats *stats = sq->stats;
prefetchw(wqe);
if (unlikely(dma_len < MLX5E_XDP_MIN_INLINE || sq->hw_mtu < dma_len)) {
stats->err++;
return false;
}
if (!check_result)
check_result = mlx5e_xmit_xdp_frame_check(sq);
if (unlikely(check_result < 0))
return false;
cseg->fm_ce_se = 0;
/* copy the inline part if required */
if (sq->min_inline_mode != MLX5_INLINE_MODE_NONE) {
memcpy(eseg->inline_hdr.start, xdptxd->data, MLX5E_XDP_MIN_INLINE);
eseg->inline_hdr.sz = cpu_to_be16(MLX5E_XDP_MIN_INLINE);
dma_len -= MLX5E_XDP_MIN_INLINE;
dma_addr += MLX5E_XDP_MIN_INLINE;
dseg++;
}
/* write the dma part */
dseg->addr = cpu_to_be64(dma_addr);
dseg->byte_count = cpu_to_be32(dma_len);
cseg->opmod_idx_opcode = cpu_to_be32((sq->pc << 8) | MLX5_OPCODE_SEND);
sq->pc++;
sq->doorbell_cseg = cseg;
mlx5e_xdpi_fifo_push(&sq->db.xdpi_fifo, xdpi);
stats->xmit++;
return true;
}
static void mlx5e_free_xdpsq_desc(struct mlx5e_xdpsq *sq,
struct mlx5e_xdp_wqe_info *wi,
u32 *xsk_frames,
bool recycle)
{
struct mlx5e_xdp_info_fifo *xdpi_fifo = &sq->db.xdpi_fifo;
u16 i;
for (i = 0; i < wi->num_pkts; i++) {
struct mlx5e_xdp_info xdpi = mlx5e_xdpi_fifo_pop(xdpi_fifo);
switch (xdpi.mode) {
case MLX5E_XDP_XMIT_MODE_FRAME:
/* XDP_TX from the XSK RQ and XDP_REDIRECT */
dma_unmap_single(sq->pdev, xdpi.frame.dma_addr,
xdpi.frame.xdpf->len, DMA_TO_DEVICE);
xdp_return_frame(xdpi.frame.xdpf);
break;
case MLX5E_XDP_XMIT_MODE_PAGE:
/* XDP_TX from the regular RQ */
mlx5e_page_release_dynamic(xdpi.page.rq, &xdpi.page.di, recycle);
break;
case MLX5E_XDP_XMIT_MODE_XSK:
/* AF_XDP send */
(*xsk_frames)++;
break;
default:
WARN_ON_ONCE(true);
}
}
}
bool mlx5e_poll_xdpsq_cq(struct mlx5e_cq *cq)
{
struct mlx5e_xdpsq *sq;
struct mlx5_cqe64 *cqe;
u32 xsk_frames = 0;
u16 sqcc;
int i;
sq = container_of(cq, struct mlx5e_xdpsq, cq);
if (unlikely(!test_bit(MLX5E_SQ_STATE_ENABLED, &sq->state)))
return false;
cqe = mlx5_cqwq_get_cqe(&cq->wq);
if (!cqe)
return false;
/* sq->cc must be updated only after mlx5_cqwq_update_db_record(),
* otherwise a cq overrun may occur
*/
sqcc = sq->cc;
i = 0;
do {
u16 wqe_counter;
bool last_wqe;
mlx5_cqwq_pop(&cq->wq);
wqe_counter = be16_to_cpu(cqe->wqe_counter);
if (unlikely(get_cqe_opcode(cqe) != MLX5_CQE_REQ))
netdev_WARN_ONCE(sq->channel->netdev,
"Bad OP in XDPSQ CQE: 0x%x\n",
get_cqe_opcode(cqe));
do {
struct mlx5e_xdp_wqe_info *wi;
u16 ci;
last_wqe = (sqcc == wqe_counter);
ci = mlx5_wq_cyc_ctr2ix(&sq->wq, sqcc);
wi = &sq->db.wqe_info[ci];
sqcc += wi->num_wqebbs;
mlx5e_free_xdpsq_desc(sq, wi, &xsk_frames, true);
} while (!last_wqe);
} while ((++i < MLX5E_TX_CQ_POLL_BUDGET) && (cqe = mlx5_cqwq_get_cqe(&cq->wq)));
if (xsk_frames)
xsk_umem_complete_tx(sq->umem, xsk_frames);
sq->stats->cqes += i;
mlx5_cqwq_update_db_record(&cq->wq);
/* ensure cq space is freed before enabling more cqes */
wmb();
sq->cc = sqcc;
return (i == MLX5E_TX_CQ_POLL_BUDGET);
}
void mlx5e_free_xdpsq_descs(struct mlx5e_xdpsq *sq)
{
u32 xsk_frames = 0;
while (sq->cc != sq->pc) {
struct mlx5e_xdp_wqe_info *wi;
u16 ci;
ci = mlx5_wq_cyc_ctr2ix(&sq->wq, sq->cc);
wi = &sq->db.wqe_info[ci];
sq->cc += wi->num_wqebbs;
mlx5e_free_xdpsq_desc(sq, wi, &xsk_frames, false);
}
if (xsk_frames)
xsk_umem_complete_tx(sq->umem, xsk_frames);
}
int mlx5e_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
u32 flags)
{
struct mlx5e_priv *priv = netdev_priv(dev);
struct mlx5e_xdpsq *sq;
int drops = 0;
int sq_num;
int i;
/* this flag is sufficient, no need to test internal sq state */
if (unlikely(!mlx5e_xdp_tx_is_enabled(priv)))
return -ENETDOWN;
if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
return -EINVAL;
sq_num = smp_processor_id();
if (unlikely(sq_num >= priv->channels.num))
return -ENXIO;
sq = &priv->channels.c[sq_num]->xdpsq;
for (i = 0; i < n; i++) {
struct xdp_frame *xdpf = frames[i];
struct mlx5e_xdp_xmit_data xdptxd;
struct mlx5e_xdp_info xdpi;
xdptxd.data = xdpf->data;
xdptxd.len = xdpf->len;
xdptxd.dma_addr = dma_map_single(sq->pdev, xdptxd.data,
xdptxd.len, DMA_TO_DEVICE);
if (unlikely(dma_mapping_error(sq->pdev, xdptxd.dma_addr))) {
xdp_return_frame_rx_napi(xdpf);
drops++;
continue;
}
xdpi.mode = MLX5E_XDP_XMIT_MODE_FRAME;
xdpi.frame.xdpf = xdpf;
xdpi.frame.dma_addr = xdptxd.dma_addr;
if (unlikely(!sq->xmit_xdp_frame(sq, &xdptxd, &xdpi, 0))) {
dma_unmap_single(sq->pdev, xdptxd.dma_addr,
xdptxd.len, DMA_TO_DEVICE);
xdp_return_frame_rx_napi(xdpf);
drops++;
}
}
if (flags & XDP_XMIT_FLUSH) {
if (sq->mpwqe.wqe)
mlx5e_xdp_mpwqe_complete(sq);
mlx5e_xmit_xdp_doorbell(sq);
}
return n - drops;
}
void mlx5e_xdp_rx_poll_complete(struct mlx5e_rq *rq)
{
struct mlx5e_xdpsq *xdpsq = rq->xdpsq;
if (xdpsq->mpwqe.wqe)
mlx5e_xdp_mpwqe_complete(xdpsq);
mlx5e_xmit_xdp_doorbell(xdpsq);
if (test_bit(MLX5E_RQ_FLAG_XDP_REDIRECT, rq->flags)) {
xdp_do_flush_map();
__clear_bit(MLX5E_RQ_FLAG_XDP_REDIRECT, rq->flags);
}
}
void mlx5e_set_xmit_fp(struct mlx5e_xdpsq *sq, bool is_mpw)
{
sq->xmit_xdp_frame_check = is_mpw ?
mlx5e_xmit_xdp_frame_check_mpwqe : mlx5e_xmit_xdp_frame_check;
sq->xmit_xdp_frame = is_mpw ?
mlx5e_xmit_xdp_frame_mpwqe : mlx5e_xmit_xdp_frame;
}
