blob: 021bbf308d685c40567e7b34fdeb69c1c755df21 [file] [log] [blame]
// SPDX-License-Identifier: (GPL-2.0 OR MIT)
/* Google virtual Ethernet (gve) driver
*
* Copyright (C) 2015-2021 Google, Inc.
*/
#include "gve.h"
#include "gve_adminq.h"
#include "gve_utils.h"
#include <linux/etherdevice.h>
static void gve_rx_free_buffer(struct device *dev,
struct gve_rx_slot_page_info *page_info,
union gve_rx_data_slot *data_slot)
{
dma_addr_t dma = (dma_addr_t)(be64_to_cpu(data_slot->addr) &
GVE_DATA_SLOT_ADDR_PAGE_MASK);
page_ref_sub(page_info->page, page_info->pagecnt_bias - 1);
gve_free_page(dev, page_info->page, dma, DMA_FROM_DEVICE);
}
static void gve_rx_unfill_pages(struct gve_priv *priv, struct gve_rx_ring *rx)
{
u32 slots = rx->mask + 1;
int i;
if (rx->data.raw_addressing) {
for (i = 0; i < slots; i++)
gve_rx_free_buffer(&priv->pdev->dev, &rx->data.page_info[i],
&rx->data.data_ring[i]);
} else {
for (i = 0; i < slots; i++)
page_ref_sub(rx->data.page_info[i].page,
rx->data.page_info[i].pagecnt_bias - 1);
gve_unassign_qpl(priv, rx->data.qpl->id);
rx->data.qpl = NULL;
}
kvfree(rx->data.page_info);
rx->data.page_info = NULL;
}
static void gve_rx_free_ring(struct gve_priv *priv, int idx)
{
struct gve_rx_ring *rx = &priv->rx[idx];
struct device *dev = &priv->pdev->dev;
u32 slots = rx->mask + 1;
size_t bytes;
gve_rx_remove_from_block(priv, idx);
bytes = sizeof(struct gve_rx_desc) * priv->rx_desc_cnt;
dma_free_coherent(dev, bytes, rx->desc.desc_ring, rx->desc.bus);
rx->desc.desc_ring = NULL;
dma_free_coherent(dev, sizeof(*rx->q_resources),
rx->q_resources, rx->q_resources_bus);
rx->q_resources = NULL;
gve_rx_unfill_pages(priv, rx);
bytes = sizeof(*rx->data.data_ring) * slots;
dma_free_coherent(dev, bytes, rx->data.data_ring,
rx->data.data_bus);
rx->data.data_ring = NULL;
netif_dbg(priv, drv, priv->dev, "freed rx ring %d\n", idx);
}
static void gve_setup_rx_buffer(struct gve_rx_slot_page_info *page_info,
dma_addr_t addr, struct page *page, __be64 *slot_addr)
{
page_info->page = page;
page_info->page_offset = 0;
page_info->page_address = page_address(page);
*slot_addr = cpu_to_be64(addr);
/* The page already has 1 ref */
page_ref_add(page, INT_MAX - 1);
page_info->pagecnt_bias = INT_MAX;
}
static int gve_rx_alloc_buffer(struct gve_priv *priv, struct device *dev,
struct gve_rx_slot_page_info *page_info,
union gve_rx_data_slot *data_slot)
{
struct page *page;
dma_addr_t dma;
int err;
err = gve_alloc_page(priv, dev, &page, &dma, DMA_FROM_DEVICE,
GFP_ATOMIC);
if (err)
return err;
gve_setup_rx_buffer(page_info, dma, page, &data_slot->addr);
return 0;
}
static int gve_prefill_rx_pages(struct gve_rx_ring *rx)
{
struct gve_priv *priv = rx->gve;
u32 slots;
int err;
int i;
/* Allocate one page per Rx queue slot. Each page is split into two
* packet buffers, when possible we "page flip" between the two.
*/
slots = rx->mask + 1;
rx->data.page_info = kvzalloc(slots *
sizeof(*rx->data.page_info), GFP_KERNEL);
if (!rx->data.page_info)
return -ENOMEM;
if (!rx->data.raw_addressing) {
rx->data.qpl = gve_assign_rx_qpl(priv);
if (!rx->data.qpl) {
kvfree(rx->data.page_info);
rx->data.page_info = NULL;
return -ENOMEM;
}
}
for (i = 0; i < slots; i++) {
if (!rx->data.raw_addressing) {
struct page *page = rx->data.qpl->pages[i];
dma_addr_t addr = i * PAGE_SIZE;
gve_setup_rx_buffer(&rx->data.page_info[i], addr, page,
&rx->data.data_ring[i].qpl_offset);
continue;
}
err = gve_rx_alloc_buffer(priv, &priv->pdev->dev, &rx->data.page_info[i],
&rx->data.data_ring[i]);
if (err)
goto alloc_err;
}
return slots;
alloc_err:
while (i--)
gve_rx_free_buffer(&priv->pdev->dev,
&rx->data.page_info[i],
&rx->data.data_ring[i]);
return err;
}
static void gve_rx_ctx_clear(struct gve_rx_ctx *ctx)
{
ctx->curr_frag_cnt = 0;
ctx->total_expected_size = 0;
ctx->expected_frag_cnt = 0;
ctx->skb_head = NULL;
ctx->skb_tail = NULL;
ctx->reuse_frags = false;
}
static int gve_rx_alloc_ring(struct gve_priv *priv, int idx)
{
struct gve_rx_ring *rx = &priv->rx[idx];
struct device *hdev = &priv->pdev->dev;
u32 slots, npages;
int filled_pages;
size_t bytes;
int err;
netif_dbg(priv, drv, priv->dev, "allocating rx ring\n");
/* Make sure everything is zeroed to start with */
memset(rx, 0, sizeof(*rx));
rx->gve = priv;
rx->q_num = idx;
slots = priv->rx_data_slot_cnt;
rx->mask = slots - 1;
rx->data.raw_addressing = priv->queue_format == GVE_GQI_RDA_FORMAT;
/* alloc rx data ring */
bytes = sizeof(*rx->data.data_ring) * slots;
rx->data.data_ring = dma_alloc_coherent(hdev, bytes,
&rx->data.data_bus,
GFP_KERNEL);
if (!rx->data.data_ring)
return -ENOMEM;
filled_pages = gve_prefill_rx_pages(rx);
if (filled_pages < 0) {
err = -ENOMEM;
goto abort_with_slots;
}
rx->fill_cnt = filled_pages;
/* Ensure data ring slots (packet buffers) are visible. */
dma_wmb();
/* Alloc gve_queue_resources */
rx->q_resources =
dma_alloc_coherent(hdev,
sizeof(*rx->q_resources),
&rx->q_resources_bus,
GFP_KERNEL);
if (!rx->q_resources) {
err = -ENOMEM;
goto abort_filled;
}
netif_dbg(priv, drv, priv->dev, "rx[%d]->data.data_bus=%lx\n", idx,
(unsigned long)rx->data.data_bus);
/* alloc rx desc ring */
bytes = sizeof(struct gve_rx_desc) * priv->rx_desc_cnt;
npages = bytes / PAGE_SIZE;
if (npages * PAGE_SIZE != bytes) {
err = -EIO;
goto abort_with_q_resources;
}
rx->desc.desc_ring = dma_alloc_coherent(hdev, bytes, &rx->desc.bus,
GFP_KERNEL);
if (!rx->desc.desc_ring) {
err = -ENOMEM;
goto abort_with_q_resources;
}
rx->cnt = 0;
rx->db_threshold = priv->rx_desc_cnt / 2;
rx->desc.seqno = 1;
/* Allocating half-page buffers allows page-flipping which is faster
* than copying or allocating new pages.
*/
rx->packet_buffer_size = PAGE_SIZE / 2;
gve_rx_ctx_clear(&rx->ctx);
gve_rx_add_to_block(priv, idx);
return 0;
abort_with_q_resources:
dma_free_coherent(hdev, sizeof(*rx->q_resources),
rx->q_resources, rx->q_resources_bus);
rx->q_resources = NULL;
abort_filled:
gve_rx_unfill_pages(priv, rx);
abort_with_slots:
bytes = sizeof(*rx->data.data_ring) * slots;
dma_free_coherent(hdev, bytes, rx->data.data_ring, rx->data.data_bus);
rx->data.data_ring = NULL;
return err;
}
int gve_rx_alloc_rings(struct gve_priv *priv)
{
int err = 0;
int i;
for (i = 0; i < priv->rx_cfg.num_queues; i++) {
err = gve_rx_alloc_ring(priv, i);
if (err) {
netif_err(priv, drv, priv->dev,
"Failed to alloc rx ring=%d: err=%d\n",
i, err);
break;
}
}
/* Unallocate if there was an error */
if (err) {
int j;
for (j = 0; j < i; j++)
gve_rx_free_ring(priv, j);
}
return err;
}
void gve_rx_free_rings_gqi(struct gve_priv *priv)
{
int i;
for (i = 0; i < priv->rx_cfg.num_queues; i++)
gve_rx_free_ring(priv, i);
}
void gve_rx_write_doorbell(struct gve_priv *priv, struct gve_rx_ring *rx)
{
u32 db_idx = be32_to_cpu(rx->q_resources->db_index);
iowrite32be(rx->fill_cnt, &priv->db_bar2[db_idx]);
}
static enum pkt_hash_types gve_rss_type(__be16 pkt_flags)
{
if (likely(pkt_flags & (GVE_RXF_TCP | GVE_RXF_UDP)))
return PKT_HASH_TYPE_L4;
if (pkt_flags & (GVE_RXF_IPV4 | GVE_RXF_IPV6))
return PKT_HASH_TYPE_L3;
return PKT_HASH_TYPE_L2;
}
static u16 gve_rx_ctx_padding(struct gve_rx_ctx *ctx)
{
return (ctx->curr_frag_cnt == 0) ? GVE_RX_PAD : 0;
}
static struct sk_buff *gve_rx_add_frags(struct napi_struct *napi,
struct gve_rx_slot_page_info *page_info,
u16 packet_buffer_size, u16 len,
struct gve_rx_ctx *ctx)
{
u32 offset = page_info->page_offset + gve_rx_ctx_padding(ctx);
struct sk_buff *skb;
if (!ctx->skb_head)
ctx->skb_head = napi_get_frags(napi);
if (unlikely(!ctx->skb_head))
return NULL;
skb = ctx->skb_head;
skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page_info->page,
offset, len, packet_buffer_size);
return skb;
}
static void gve_rx_flip_buff(struct gve_rx_slot_page_info *page_info, __be64 *slot_addr)
{
const __be64 offset = cpu_to_be64(PAGE_SIZE / 2);
/* "flip" to other packet buffer on this page */
page_info->page_offset ^= PAGE_SIZE / 2;
*(slot_addr) ^= offset;
}
static int gve_rx_can_recycle_buffer(struct gve_rx_slot_page_info *page_info)
{
int pagecount = page_count(page_info->page);
/* This page is not being used by any SKBs - reuse */
if (pagecount == page_info->pagecnt_bias)
return 1;
/* This page is still being used by an SKB - we can't reuse */
else if (pagecount > page_info->pagecnt_bias)
return 0;
WARN(pagecount < page_info->pagecnt_bias,
"Pagecount should never be less than the bias.");
return -1;
}
static struct sk_buff *
gve_rx_raw_addressing(struct device *dev, struct net_device *netdev,
struct gve_rx_slot_page_info *page_info, u16 len,
struct napi_struct *napi,
union gve_rx_data_slot *data_slot,
u16 packet_buffer_size, struct gve_rx_ctx *ctx)
{
struct sk_buff *skb = gve_rx_add_frags(napi, page_info, packet_buffer_size, len, ctx);
if (!skb)
return NULL;
/* Optimistically stop the kernel from freeing the page.
* We will check again in refill to determine if we need to alloc a
* new page.
*/
gve_dec_pagecnt_bias(page_info);
return skb;
}
static struct sk_buff *
gve_rx_qpl(struct device *dev, struct net_device *netdev,
struct gve_rx_ring *rx, struct gve_rx_slot_page_info *page_info,
u16 len, struct napi_struct *napi,
union gve_rx_data_slot *data_slot)
{
struct gve_rx_ctx *ctx = &rx->ctx;
struct sk_buff *skb;
/* if raw_addressing mode is not enabled gvnic can only receive into
* registered segments. If the buffer can't be recycled, our only
* choice is to copy the data out of it so that we can return it to the
* device.
*/
if (ctx->reuse_frags) {
skb = gve_rx_add_frags(napi, page_info, rx->packet_buffer_size, len, ctx);
/* No point in recycling if we didn't get the skb */
if (skb) {
/* Make sure that the page isn't freed. */
gve_dec_pagecnt_bias(page_info);
gve_rx_flip_buff(page_info, &data_slot->qpl_offset);
}
} else {
const u16 padding = gve_rx_ctx_padding(ctx);
skb = gve_rx_copy(netdev, napi, page_info, len, padding, ctx);
if (skb) {
u64_stats_update_begin(&rx->statss);
rx->rx_frag_copy_cnt++;
u64_stats_update_end(&rx->statss);
}
}
return skb;
}
#define GVE_PKTCONT_BIT_IS_SET(x) (GVE_RXF_PKT_CONT & (x))
static u16 gve_rx_get_fragment_size(struct gve_rx_ctx *ctx, struct gve_rx_desc *desc)
{
return be16_to_cpu(desc->len) - gve_rx_ctx_padding(ctx);
}
static bool gve_rx_ctx_init(struct gve_rx_ctx *ctx, struct gve_rx_ring *rx)
{
bool qpl_mode = !rx->data.raw_addressing, packet_size_error = false;
bool buffer_error = false, desc_error = false, seqno_error = false;
struct gve_rx_slot_page_info *page_info;
struct gve_priv *priv = rx->gve;
u32 idx = rx->cnt & rx->mask;
bool reuse_frags, can_flip;
struct gve_rx_desc *desc;
u16 packet_size = 0;
u16 n_frags = 0;
int recycle;
/** In QPL mode, we only flip buffers when all buffers containing the packet
* can be flipped. RDA can_flip decisions will be made later, per frag.
*/
can_flip = qpl_mode;
reuse_frags = can_flip;
do {
u16 frag_size;
n_frags++;
desc = &rx->desc.desc_ring[idx];
desc_error = unlikely(desc->flags_seq & GVE_RXF_ERR) || desc_error;
if (GVE_SEQNO(desc->flags_seq) != rx->desc.seqno) {
seqno_error = true;
netdev_warn(priv->dev,
"RX seqno error: want=%d, got=%d, dropping packet and scheduling reset.",
rx->desc.seqno, GVE_SEQNO(desc->flags_seq));
}
frag_size = be16_to_cpu(desc->len);
packet_size += frag_size;
if (frag_size > rx->packet_buffer_size) {
packet_size_error = true;
netdev_warn(priv->dev,
"RX fragment error: packet_buffer_size=%d, frag_size=%d, dropping packet.",
rx->packet_buffer_size, be16_to_cpu(desc->len));
}
page_info = &rx->data.page_info[idx];
if (can_flip) {
recycle = gve_rx_can_recycle_buffer(page_info);
reuse_frags = reuse_frags && recycle > 0;
buffer_error = buffer_error || unlikely(recycle < 0);
}
idx = (idx + 1) & rx->mask;
rx->desc.seqno = gve_next_seqno(rx->desc.seqno);
} while (GVE_PKTCONT_BIT_IS_SET(desc->flags_seq));
prefetch(rx->desc.desc_ring + idx);
ctx->curr_frag_cnt = 0;
ctx->total_expected_size = packet_size - GVE_RX_PAD;
ctx->expected_frag_cnt = n_frags;
ctx->skb_head = NULL;
ctx->reuse_frags = reuse_frags;
if (ctx->expected_frag_cnt > 1) {
u64_stats_update_begin(&rx->statss);
rx->rx_cont_packet_cnt++;
u64_stats_update_end(&rx->statss);
}
if (ctx->total_expected_size > priv->rx_copybreak && !ctx->reuse_frags && qpl_mode) {
u64_stats_update_begin(&rx->statss);
rx->rx_copied_pkt++;
u64_stats_update_end(&rx->statss);
}
if (unlikely(buffer_error || seqno_error || packet_size_error)) {
gve_schedule_reset(priv);
return false;
}
if (unlikely(desc_error)) {
u64_stats_update_begin(&rx->statss);
rx->rx_desc_err_dropped_pkt++;
u64_stats_update_end(&rx->statss);
return false;
}
return true;
}
static struct sk_buff *gve_rx_skb(struct gve_priv *priv, struct gve_rx_ring *rx,
struct gve_rx_slot_page_info *page_info, struct napi_struct *napi,
u16 len, union gve_rx_data_slot *data_slot)
{
struct net_device *netdev = priv->dev;
struct gve_rx_ctx *ctx = &rx->ctx;
struct sk_buff *skb = NULL;
if (len <= priv->rx_copybreak && ctx->expected_frag_cnt == 1) {
/* Just copy small packets */
skb = gve_rx_copy(netdev, napi, page_info, len, GVE_RX_PAD, ctx);
if (skb) {
u64_stats_update_begin(&rx->statss);
rx->rx_copied_pkt++;
rx->rx_frag_copy_cnt++;
rx->rx_copybreak_pkt++;
u64_stats_update_end(&rx->statss);
}
} else {
if (rx->data.raw_addressing) {
int recycle = gve_rx_can_recycle_buffer(page_info);
if (unlikely(recycle < 0)) {
gve_schedule_reset(priv);
return NULL;
}
page_info->can_flip = recycle;
if (page_info->can_flip) {
u64_stats_update_begin(&rx->statss);
rx->rx_frag_flip_cnt++;
u64_stats_update_end(&rx->statss);
}
skb = gve_rx_raw_addressing(&priv->pdev->dev, netdev,
page_info, len, napi,
data_slot,
rx->packet_buffer_size, ctx);
} else {
if (ctx->reuse_frags) {
u64_stats_update_begin(&rx->statss);
rx->rx_frag_flip_cnt++;
u64_stats_update_end(&rx->statss);
}
skb = gve_rx_qpl(&priv->pdev->dev, netdev, rx,
page_info, len, napi, data_slot);
}
}
return skb;
}
static bool gve_rx(struct gve_rx_ring *rx, netdev_features_t feat,
u64 *packet_size_bytes, u32 *work_done)
{
struct gve_rx_slot_page_info *page_info;
struct gve_rx_ctx *ctx = &rx->ctx;
union gve_rx_data_slot *data_slot;
struct gve_priv *priv = rx->gve;
struct gve_rx_desc *first_desc;
struct sk_buff *skb = NULL;
struct gve_rx_desc *desc;
struct napi_struct *napi;
dma_addr_t page_bus;
u32 work_cnt = 0;
void *va;
u32 idx;
u16 len;
idx = rx->cnt & rx->mask;
first_desc = &rx->desc.desc_ring[idx];
desc = first_desc;
napi = &priv->ntfy_blocks[rx->ntfy_id].napi;
if (unlikely(!gve_rx_ctx_init(ctx, rx)))
goto skb_alloc_fail;
while (ctx->curr_frag_cnt < ctx->expected_frag_cnt) {
/* Prefetch two packet buffers ahead, we will need it soon. */
page_info = &rx->data.page_info[(idx + 2) & rx->mask];
va = page_info->page_address + page_info->page_offset;
prefetch(page_info->page); /* Kernel page struct. */
prefetch(va); /* Packet header. */
prefetch(va + 64); /* Next cacheline too. */
len = gve_rx_get_fragment_size(ctx, desc);
page_info = &rx->data.page_info[idx];
data_slot = &rx->data.data_ring[idx];
page_bus = rx->data.raw_addressing ?
be64_to_cpu(data_slot->addr) - page_info->page_offset :
rx->data.qpl->page_buses[idx];
dma_sync_single_for_cpu(&priv->pdev->dev, page_bus, PAGE_SIZE, DMA_FROM_DEVICE);
skb = gve_rx_skb(priv, rx, page_info, napi, len, data_slot);
if (!skb) {
u64_stats_update_begin(&rx->statss);
rx->rx_skb_alloc_fail++;
u64_stats_update_end(&rx->statss);
goto skb_alloc_fail;
}
ctx->curr_frag_cnt++;
rx->cnt++;
idx = rx->cnt & rx->mask;
work_cnt++;
desc = &rx->desc.desc_ring[idx];
}
if (likely(feat & NETIF_F_RXCSUM)) {
/* NIC passes up the partial sum */
if (first_desc->csum)
skb->ip_summed = CHECKSUM_COMPLETE;
else
skb->ip_summed = CHECKSUM_NONE;
skb->csum = csum_unfold(first_desc->csum);
}
/* parse flags & pass relevant info up */
if (likely(feat & NETIF_F_RXHASH) &&
gve_needs_rss(first_desc->flags_seq))
skb_set_hash(skb, be32_to_cpu(first_desc->rss_hash),
gve_rss_type(first_desc->flags_seq));
*packet_size_bytes = skb->len + (skb->protocol ? ETH_HLEN : 0);
*work_done = work_cnt;
skb_record_rx_queue(skb, rx->q_num);
if (skb_is_nonlinear(skb))
napi_gro_frags(napi);
else
napi_gro_receive(napi, skb);
gve_rx_ctx_clear(ctx);
return true;
skb_alloc_fail:
if (napi->skb)
napi_free_frags(napi);
*packet_size_bytes = 0;
*work_done = ctx->expected_frag_cnt;
while (ctx->curr_frag_cnt < ctx->expected_frag_cnt) {
rx->cnt++;
ctx->curr_frag_cnt++;
}
gve_rx_ctx_clear(ctx);
return false;
}
bool gve_rx_work_pending(struct gve_rx_ring *rx)
{
struct gve_rx_desc *desc;
__be16 flags_seq;
u32 next_idx;
next_idx = rx->cnt & rx->mask;
desc = rx->desc.desc_ring + next_idx;
flags_seq = desc->flags_seq;
return (GVE_SEQNO(flags_seq) == rx->desc.seqno);
}
static bool gve_rx_refill_buffers(struct gve_priv *priv, struct gve_rx_ring *rx)
{
int refill_target = rx->mask + 1;
u32 fill_cnt = rx->fill_cnt;
while (fill_cnt - rx->cnt < refill_target) {
struct gve_rx_slot_page_info *page_info;
u32 idx = fill_cnt & rx->mask;
page_info = &rx->data.page_info[idx];
if (page_info->can_flip) {
/* The other half of the page is free because it was
* free when we processed the descriptor. Flip to it.
*/
union gve_rx_data_slot *data_slot =
&rx->data.data_ring[idx];
gve_rx_flip_buff(page_info, &data_slot->addr);
page_info->can_flip = 0;
} else {
/* It is possible that the networking stack has already
* finished processing all outstanding packets in the buffer
* and it can be reused.
* Flipping is unnecessary here - if the networking stack still
* owns half the page it is impossible to tell which half. Either
* the whole page is free or it needs to be replaced.
*/
int recycle = gve_rx_can_recycle_buffer(page_info);
if (recycle < 0) {
if (!rx->data.raw_addressing)
gve_schedule_reset(priv);
return false;
}
if (!recycle) {
/* We can't reuse the buffer - alloc a new one*/
union gve_rx_data_slot *data_slot =
&rx->data.data_ring[idx];
struct device *dev = &priv->pdev->dev;
gve_rx_free_buffer(dev, page_info, data_slot);
page_info->page = NULL;
if (gve_rx_alloc_buffer(priv, dev, page_info,
data_slot)) {
u64_stats_update_begin(&rx->statss);
rx->rx_buf_alloc_fail++;
u64_stats_update_end(&rx->statss);
break;
}
}
}
fill_cnt++;
}
rx->fill_cnt = fill_cnt;
return true;
}
static int gve_clean_rx_done(struct gve_rx_ring *rx, int budget,
netdev_features_t feat)
{
u32 work_done = 0, total_packet_cnt = 0, ok_packet_cnt = 0;
struct gve_priv *priv = rx->gve;
u32 idx = rx->cnt & rx->mask;
struct gve_rx_desc *desc;
u64 bytes = 0;
desc = &rx->desc.desc_ring[idx];
while ((GVE_SEQNO(desc->flags_seq) == rx->desc.seqno) &&
work_done < budget) {
u64 packet_size_bytes = 0;
u32 work_cnt = 0;
bool dropped;
netif_info(priv, rx_status, priv->dev,
"[%d] idx=%d desc=%p desc->flags_seq=0x%x\n",
rx->q_num, idx, desc, desc->flags_seq);
netif_info(priv, rx_status, priv->dev,
"[%d] seqno=%d rx->desc.seqno=%d\n",
rx->q_num, GVE_SEQNO(desc->flags_seq),
rx->desc.seqno);
dropped = !gve_rx(rx, feat, &packet_size_bytes, &work_cnt);
if (!dropped) {
bytes += packet_size_bytes;
ok_packet_cnt++;
}
total_packet_cnt++;
idx = rx->cnt & rx->mask;
desc = &rx->desc.desc_ring[idx];
work_done += work_cnt;
}
if (!work_done && rx->fill_cnt - rx->cnt > rx->db_threshold)
return 0;
if (work_done) {
u64_stats_update_begin(&rx->statss);
rx->rpackets += ok_packet_cnt;
rx->rbytes += bytes;
u64_stats_update_end(&rx->statss);
}
/* restock ring slots */
if (!rx->data.raw_addressing) {
/* In QPL mode buffs are refilled as the desc are processed */
rx->fill_cnt += work_done;
} else if (rx->fill_cnt - rx->cnt <= rx->db_threshold) {
/* In raw addressing mode buffs are only refilled if the avail
* falls below a threshold.
*/
if (!gve_rx_refill_buffers(priv, rx))
return 0;
/* If we were not able to completely refill buffers, we'll want
* to schedule this queue for work again to refill buffers.
*/
if (rx->fill_cnt - rx->cnt <= rx->db_threshold) {
gve_rx_write_doorbell(priv, rx);
return budget;
}
}
gve_rx_write_doorbell(priv, rx);
return total_packet_cnt;
}
int gve_rx_poll(struct gve_notify_block *block, int budget)
{
struct gve_rx_ring *rx = block->rx;
netdev_features_t feat;
int work_done = 0;
feat = block->napi.dev->features;
/* If budget is 0, do all the work */
if (budget == 0)
budget = INT_MAX;
if (budget > 0)
work_done = gve_clean_rx_done(rx, budget, feat);
return work_done;
}