1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/skbuff.h> 3 #include <linux/slab.h> 4 #include <linux/netdevice.h> 5 #include <net/gro_cells.h> 6 7 struct gro_cell { 8 struct sk_buff_head napi_skbs; 9 struct napi_struct napi; 10 }; 11 12 int gro_cells_receive(struct gro_cells *gcells, struct sk_buff *skb) 13 { 14 struct net_device *dev = skb->dev; 15 struct gro_cell *cell; 16 17 if (!gcells->cells || skb_cloned(skb) || netif_elide_gro(dev)) 18 return netif_rx(skb); 19 20 cell = this_cpu_ptr(gcells->cells); 21 22 if (skb_queue_len(&cell->napi_skbs) > netdev_max_backlog) { 23 atomic_long_inc(&dev->rx_dropped); 24 kfree_skb(skb); 25 return NET_RX_DROP; 26 } 27 28 __skb_queue_tail(&cell->napi_skbs, skb); 29 if (skb_queue_len(&cell->napi_skbs) == 1) 30 napi_schedule(&cell->napi); 31 return NET_RX_SUCCESS; 32 } 33 EXPORT_SYMBOL(gro_cells_receive); 34 35 /* called under BH context */ 36 static int gro_cell_poll(struct napi_struct *napi, int budget) 37 { 38 struct gro_cell *cell = container_of(napi, struct gro_cell, napi); 39 struct sk_buff *skb; 40 int work_done = 0; 41 42 while (work_done < budget) { 43 skb = __skb_dequeue(&cell->napi_skbs); 44 if (!skb) 45 break; 46 napi_gro_receive(napi, skb); 47 work_done++; 48 } 49 50 if (work_done < budget) 51 napi_complete_done(napi, work_done); 52 return work_done; 53 } 54 55 int gro_cells_init(struct gro_cells *gcells, struct net_device *dev) 56 { 57 int i; 58 59 gcells->cells = alloc_percpu(struct gro_cell); 60 if (!gcells->cells) 61 return -ENOMEM; 62 63 for_each_possible_cpu(i) { 64 struct gro_cell *cell = per_cpu_ptr(gcells->cells, i); 65 66 __skb_queue_head_init(&cell->napi_skbs); 67 68 set_bit(NAPI_STATE_NO_BUSY_POLL, &cell->napi.state); 69 70 netif_napi_add(dev, &cell->napi, gro_cell_poll, 71 NAPI_POLL_WEIGHT); 72 napi_enable(&cell->napi); 73 } 74 return 0; 75 } 76 EXPORT_SYMBOL(gro_cells_init); 77 78 void gro_cells_destroy(struct gro_cells *gcells) 79 { 80 int i; 81 82 if (!gcells->cells) 83 return; 84 for_each_possible_cpu(i) { 85 struct gro_cell *cell = per_cpu_ptr(gcells->cells, i); 86 87 napi_disable(&cell->napi); 88 netif_napi_del(&cell->napi); 89 __skb_queue_purge(&cell->napi_skbs); 90 } 91 free_percpu(gcells->cells); 92 gcells->cells = NULL; 93 } 94 EXPORT_SYMBOL(gro_cells_destroy); 95