1#ifndef _NET_GRO_CELLS_H
 2#define _NET_GRO_CELLS_H
 3
 4#include <linux/skbuff.h>
 5#include <linux/slab.h>
 6#include <linux/netdevice.h>
 7
 8struct gro_cell {
 9	struct sk_buff_head	napi_skbs;
10	struct napi_struct	napi;
11};
12
13struct gro_cells {
14	struct gro_cell __percpu	*cells;
15};
16
17static inline int gro_cells_receive(struct gro_cells *gcells, struct sk_buff *skb)
18{
19	struct gro_cell *cell;
20	struct net_device *dev = skb->dev;
21
22	if (!gcells->cells || skb_cloned(skb) || !(dev->features & NETIF_F_GRO))
23		return netif_rx(skb);
24
25	cell = this_cpu_ptr(gcells->cells);
26
27	if (skb_queue_len(&cell->napi_skbs) > netdev_max_backlog) {
28		atomic_long_inc(&dev->rx_dropped);
29		kfree_skb(skb);
30		return NET_RX_DROP;
31	}
32
33	__skb_queue_tail(&cell->napi_skbs, skb);
34	if (skb_queue_len(&cell->napi_skbs) == 1)
35		napi_schedule(&cell->napi);
36	return NET_RX_SUCCESS;
37}
38
39/* called under BH context */
40static inline int gro_cell_poll(struct napi_struct *napi, int budget)
41{
42	struct gro_cell *cell = container_of(napi, struct gro_cell, napi);
43	struct sk_buff *skb;
44	int work_done = 0;
45
46	while (work_done < budget) {
47		skb = __skb_dequeue(&cell->napi_skbs);
48		if (!skb)
49			break;
50		napi_gro_receive(napi, skb);
51		work_done++;
52	}
53
54	if (work_done < budget)
55		napi_complete_done(napi, work_done);
56	return work_done;
57}
58
59static inline int gro_cells_init(struct gro_cells *gcells, struct net_device *dev)
60{
61	int i;
62
63	gcells->cells = alloc_percpu(struct gro_cell);
64	if (!gcells->cells)
65		return -ENOMEM;
66
67	for_each_possible_cpu(i) {
68		struct gro_cell *cell = per_cpu_ptr(gcells->cells, i);
69
70		__skb_queue_head_init(&cell->napi_skbs);
71
72		set_bit(NAPI_STATE_NO_BUSY_POLL, &cell->napi.state);
73
74		netif_napi_add(dev, &cell->napi, gro_cell_poll, 64);
75		napi_enable(&cell->napi);
76	}
77	return 0;
78}
79
80static inline void gro_cells_destroy(struct gro_cells *gcells)
81{
82	int i;
83
84	if (!gcells->cells)
85		return;
86	for_each_possible_cpu(i) {
87		struct gro_cell *cell = per_cpu_ptr(gcells->cells, i);
88
89		netif_napi_del(&cell->napi);
90		__skb_queue_purge(&cell->napi_skbs);
91	}
92	free_percpu(gcells->cells);
93	gcells->cells = NULL;
94}
95
96#endif