#ifndef _NET_GRO_CELLS_H
#define _NET_GRO_CELLS_H

#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/netdevice.h>

struct gro_cell {
struct sk_buff_head napi_skbs;
struct napi_struct napi;
} ____cacheline_aligned_in_smp;

struct gro_cells {
unsigned int gro_cells_mask;
struct gro_cell *cells;
};

static inline void gro_cells_receive(struct gro_cells *gcells, struct sk_buff *skb)
{
struct gro_cell *cell = gcells->cells;
struct net_device *dev = skb->dev;

if (!cell || skb_cloned(skb) || !(dev->features & NETIF_F_GRO)) {
netif_rx(skb);
return;
}

if (skb_rx_queue_recorded(skb))
cell += skb_get_rx_queue(skb) & gcells->gro_cells_mask;

if (skb_queue_len(&cell->napi_skbs) > netdev_max_backlog) {
atomic_long_inc(&dev->rx_dropped);
kfree_skb(skb);
return;
}

/* We run in BH context */
spin_lock(&cell->napi_skbs.lock);

__skb_queue_tail(&cell->napi_skbs, skb);
if (skb_queue_len(&cell->napi_skbs) == 1)
napi_schedule(&cell->napi);

spin_unlock(&cell->napi_skbs.lock);
}

/* called unser BH context */
static inline int gro_cell_poll(struct napi_struct *napi, int budget)
{
struct gro_cell *cell = container_of(napi, struct gro_cell, napi);
struct sk_buff *skb;
int work_done = 0;

spin_lock(&cell->napi_skbs.lock);
while (work_done < budget) {
skb = __skb_dequeue(&cell->napi_skbs);
if (!skb)
break;
spin_unlock(&cell->napi_skbs.lock);
napi_gro_receive(napi, skb);
work_done++;
spin_lock(&cell->napi_skbs.lock);
}

if (work_done < budget)
napi_complete(napi);
spin_unlock(&cell->napi_skbs.lock);
return work_done;
}

static inline int gro_cells_init(struct gro_cells *gcells, struct net_device *dev)
{
int i;

gcells->gro_cells_mask = roundup_pow_of_two(netif_get_num_default_rss_queues()) - 1;
gcells->cells = kcalloc(gcells->gro_cells_mask + 1,
sizeof(struct gro_cell),
GFP_KERNEL);
if (!gcells->cells)
return -ENOMEM;

for (i = 0; i <= gcells->gro_cells_mask; i++) {
struct gro_cell *cell = gcells->cells + i;

skb_queue_head_init(&cell->napi_skbs);
netif_napi_add(dev, &cell->napi, gro_cell_poll, 64);
napi_enable(&cell->napi);
}
return 0;
}

static inline void gro_cells_destroy(struct gro_cells *gcells)
{
struct gro_cell *cell = gcells->cells;
int i;

if (!cell)
return;
for (i = 0; i <= gcells->gro_cells_mask; i++,cell++) {
netif_napi_del(&cell->napi);
skb_queue_purge(&cell->napi_skbs);
}
kfree(gcells->cells);
gcells->cells = NULL;
}

#endif