1/* 2 * Copyright (c) 2003-2008 Chelsio, Inc. All rights reserved. 3 * 4 * This software is available to you under a choice of one of two 5 * licenses. You may choose to be licensed under the terms of the GNU 6 * General Public License (GPL) Version 2, available from the file 7 * COPYING in the main directory of this source tree, or the 8 * OpenIB.org BSD license below: 9 * 10 * Redistribution and use in source and binary forms, with or 11 * without modification, are permitted provided that the following 12 * conditions are met: 13 * 14 * - Redistributions of source code must retain the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer. 17 * 18 * - Redistributions in binary form must reproduce the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer in the documentation and/or other materials 21 * provided with the distribution. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 30 * SOFTWARE. 31 */ 32#ifndef _CHELSIO_L2T_H 33#define _CHELSIO_L2T_H 34 35#include <linux/spinlock.h> 36#include "t3cdev.h" 37#include <asm/atomic.h> 38 39enum { 40 L2T_STATE_VALID, /* entry is up to date */ 41 L2T_STATE_STALE, /* entry may be used but needs revalidation */ 42 L2T_STATE_RESOLVING, /* entry needs address resolution */ 43 L2T_STATE_UNUSED /* entry not in use */ 44}; 45 46struct neighbour; 47struct sk_buff; 48 49/* 50 * Each L2T entry plays multiple roles. First of all, it keeps state for the 51 * corresponding entry of the HW L2 table and maintains a queue of offload 52 * packets awaiting address resolution. Second, it is a node of a hash table 53 * chain, where the nodes of the chain are linked together through their next 54 * pointer. Finally, each node is a bucket of a hash table, pointing to the 55 * first element in its chain through its first pointer. 56 */ 57struct l2t_entry { 58 u16 state; /* entry state */ 59 u16 idx; /* entry index */ 60 u32 addr; /* dest IP address */ 61 int ifindex; /* neighbor's net_device's ifindex */ 62 u16 smt_idx; /* SMT index */ 63 u16 vlan; /* VLAN TCI (id: bits 0-11, prio: 13-15 */ 64 struct neighbour *neigh; /* associated neighbour */ 65 struct l2t_entry *first; /* start of hash chain */ 66 struct l2t_entry *next; /* next l2t_entry on chain */ 67 struct sk_buff_head arpq; /* queue of packets awaiting resolution */ 68 spinlock_t lock; 69 atomic_t refcnt; /* entry reference count */ 70 u8 dmac[6]; /* neighbour's MAC address */ 71}; 72 73struct l2t_data { 74 unsigned int nentries; /* number of entries */ 75 struct l2t_entry *rover; /* starting point for next allocation */ 76 atomic_t nfree; /* number of free entries */ 77 rwlock_t lock; 78 struct l2t_entry l2tab[0]; 79}; 80 81typedef void (*arp_failure_handler_func)(struct t3cdev * dev, 82 struct sk_buff * skb); 83 84/* 85 * Callback stored in an skb to handle address resolution failure. 86 */ 87struct l2t_skb_cb { 88 arp_failure_handler_func arp_failure_handler; 89}; 90 91#define L2T_SKB_CB(skb) ((struct l2t_skb_cb *)(skb)->cb) 92 93static inline void set_arp_failure_handler(struct sk_buff *skb, 94 arp_failure_handler_func hnd) 95{ 96 L2T_SKB_CB(skb)->arp_failure_handler = hnd; 97} 98 99/* 100 * Getting to the L2 data from an offload device. 101 */ 102#define L2DATA(dev) ((dev)->l2opt) 103 104#define W_TCB_L2T_IX 0 105#define S_TCB_L2T_IX 7 106#define M_TCB_L2T_IX 0x7ffULL 107#define V_TCB_L2T_IX(x) ((x) << S_TCB_L2T_IX) 108 109void t3_l2e_free(struct l2t_data *d, struct l2t_entry *e); 110void t3_l2t_update(struct t3cdev *dev, struct neighbour *neigh); 111struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh, 112 struct net_device *dev); 113int t3_l2t_send_slow(struct t3cdev *dev, struct sk_buff *skb, 114 struct l2t_entry *e); 115void t3_l2t_send_event(struct t3cdev *dev, struct l2t_entry *e); 116struct l2t_data *t3_init_l2t(unsigned int l2t_capacity); 117void t3_free_l2t(struct l2t_data *d); 118 119int cxgb3_ofld_send(struct t3cdev *dev, struct sk_buff *skb); 120 121static inline int l2t_send(struct t3cdev *dev, struct sk_buff *skb, 122 struct l2t_entry *e) 123{ 124 if (likely(e->state == L2T_STATE_VALID)) 125 return cxgb3_ofld_send(dev, skb); 126 return t3_l2t_send_slow(dev, skb, e); 127} 128 129static inline void l2t_release(struct l2t_data *d, struct l2t_entry *e) 130{ 131 if (atomic_dec_and_test(&e->refcnt)) 132 t3_l2e_free(d, e); 133} 134 135static inline void l2t_hold(struct l2t_data *d, struct l2t_entry *e) 136{ 137 if (atomic_add_return(1, &e->refcnt) == 1) /* 0 -> 1 transition */ 138 atomic_dec(&d->nfree); 139} 140 141#endif 142