1f7917c00SJeff Kirsher /* 2f7917c00SJeff Kirsher * Copyright (c) 2003-2008 Chelsio, Inc. All rights reserved. 3f7917c00SJeff Kirsher * 4f7917c00SJeff Kirsher * This software is available to you under a choice of one of two 5f7917c00SJeff Kirsher * licenses. You may choose to be licensed under the terms of the GNU 6f7917c00SJeff Kirsher * General Public License (GPL) Version 2, available from the file 7f7917c00SJeff Kirsher * COPYING in the main directory of this source tree, or the 8f7917c00SJeff Kirsher * OpenIB.org BSD license below: 9f7917c00SJeff Kirsher * 10f7917c00SJeff Kirsher * Redistribution and use in source and binary forms, with or 11f7917c00SJeff Kirsher * without modification, are permitted provided that the following 12f7917c00SJeff Kirsher * conditions are met: 13f7917c00SJeff Kirsher * 14f7917c00SJeff Kirsher * - Redistributions of source code must retain the above 15f7917c00SJeff Kirsher * copyright notice, this list of conditions and the following 16f7917c00SJeff Kirsher * disclaimer. 17f7917c00SJeff Kirsher * 18f7917c00SJeff Kirsher * - Redistributions in binary form must reproduce the above 19f7917c00SJeff Kirsher * copyright notice, this list of conditions and the following 20f7917c00SJeff Kirsher * disclaimer in the documentation and/or other materials 21f7917c00SJeff Kirsher * provided with the distribution. 22f7917c00SJeff Kirsher * 23f7917c00SJeff Kirsher * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24f7917c00SJeff Kirsher * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25f7917c00SJeff Kirsher * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 26f7917c00SJeff Kirsher * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 27f7917c00SJeff Kirsher * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 28f7917c00SJeff Kirsher * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 29f7917c00SJeff Kirsher * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 30f7917c00SJeff Kirsher * SOFTWARE. 31f7917c00SJeff Kirsher */ 32f7917c00SJeff Kirsher #ifndef _CHELSIO_L2T_H 33f7917c00SJeff Kirsher #define _CHELSIO_L2T_H 34f7917c00SJeff Kirsher 35f7917c00SJeff Kirsher #include <linux/spinlock.h> 36f7917c00SJeff Kirsher #include "t3cdev.h" 37f7917c00SJeff Kirsher #include <linux/atomic.h> 38f7917c00SJeff Kirsher 39f7917c00SJeff Kirsher enum { 40f7917c00SJeff Kirsher L2T_STATE_VALID, /* entry is up to date */ 41f7917c00SJeff Kirsher L2T_STATE_STALE, /* entry may be used but needs revalidation */ 42f7917c00SJeff Kirsher L2T_STATE_RESOLVING, /* entry needs address resolution */ 43f7917c00SJeff Kirsher L2T_STATE_UNUSED /* entry not in use */ 44f7917c00SJeff Kirsher }; 45f7917c00SJeff Kirsher 46f7917c00SJeff Kirsher struct neighbour; 47f7917c00SJeff Kirsher struct sk_buff; 48f7917c00SJeff Kirsher 49f7917c00SJeff Kirsher /* 50f7917c00SJeff Kirsher * Each L2T entry plays multiple roles. First of all, it keeps state for the 51f7917c00SJeff Kirsher * corresponding entry of the HW L2 table and maintains a queue of offload 52f7917c00SJeff Kirsher * packets awaiting address resolution. Second, it is a node of a hash table 53f7917c00SJeff Kirsher * chain, where the nodes of the chain are linked together through their next 54f7917c00SJeff Kirsher * pointer. Finally, each node is a bucket of a hash table, pointing to the 55f7917c00SJeff Kirsher * first element in its chain through its first pointer. 56f7917c00SJeff Kirsher */ 57f7917c00SJeff Kirsher struct l2t_entry { 58f7917c00SJeff Kirsher u16 state; /* entry state */ 59f7917c00SJeff Kirsher u16 idx; /* entry index */ 60f7917c00SJeff Kirsher u32 addr; /* dest IP address */ 61f7917c00SJeff Kirsher int ifindex; /* neighbor's net_device's ifindex */ 62f7917c00SJeff Kirsher u16 smt_idx; /* SMT index */ 63f7917c00SJeff Kirsher u16 vlan; /* VLAN TCI (id: bits 0-11, prio: 13-15 */ 64f7917c00SJeff Kirsher struct neighbour *neigh; /* associated neighbour */ 65f7917c00SJeff Kirsher struct l2t_entry *first; /* start of hash chain */ 66f7917c00SJeff Kirsher struct l2t_entry *next; /* next l2t_entry on chain */ 67f7917c00SJeff Kirsher struct sk_buff_head arpq; /* queue of packets awaiting resolution */ 68f7917c00SJeff Kirsher spinlock_t lock; 69f7917c00SJeff Kirsher atomic_t refcnt; /* entry reference count */ 70f7917c00SJeff Kirsher u8 dmac[6]; /* neighbour's MAC address */ 71f7917c00SJeff Kirsher }; 72f7917c00SJeff Kirsher 73f7917c00SJeff Kirsher struct l2t_data { 74f7917c00SJeff Kirsher unsigned int nentries; /* number of entries */ 75f7917c00SJeff Kirsher struct l2t_entry *rover; /* starting point for next allocation */ 76f7917c00SJeff Kirsher atomic_t nfree; /* number of free entries */ 77f7917c00SJeff Kirsher rwlock_t lock; 78f7917c00SJeff Kirsher struct l2t_entry l2tab[0]; 79f7917c00SJeff Kirsher }; 80f7917c00SJeff Kirsher 81f7917c00SJeff Kirsher typedef void (*arp_failure_handler_func)(struct t3cdev * dev, 82f7917c00SJeff Kirsher struct sk_buff * skb); 83f7917c00SJeff Kirsher 84f7917c00SJeff Kirsher /* 85f7917c00SJeff Kirsher * Callback stored in an skb to handle address resolution failure. 86f7917c00SJeff Kirsher */ 87f7917c00SJeff Kirsher struct l2t_skb_cb { 88f7917c00SJeff Kirsher arp_failure_handler_func arp_failure_handler; 89f7917c00SJeff Kirsher }; 90f7917c00SJeff Kirsher 91f7917c00SJeff Kirsher #define L2T_SKB_CB(skb) ((struct l2t_skb_cb *)(skb)->cb) 92f7917c00SJeff Kirsher 93f7917c00SJeff Kirsher static inline void set_arp_failure_handler(struct sk_buff *skb, 94f7917c00SJeff Kirsher arp_failure_handler_func hnd) 95f7917c00SJeff Kirsher { 96f7917c00SJeff Kirsher L2T_SKB_CB(skb)->arp_failure_handler = hnd; 97f7917c00SJeff Kirsher } 98f7917c00SJeff Kirsher 99f7917c00SJeff Kirsher /* 100f7917c00SJeff Kirsher * Getting to the L2 data from an offload device. 101f7917c00SJeff Kirsher */ 102f7917c00SJeff Kirsher #define L2DATA(dev) ((dev)->l2opt) 103f7917c00SJeff Kirsher 104f7917c00SJeff Kirsher #define W_TCB_L2T_IX 0 105f7917c00SJeff Kirsher #define S_TCB_L2T_IX 7 106f7917c00SJeff Kirsher #define M_TCB_L2T_IX 0x7ffULL 107f7917c00SJeff Kirsher #define V_TCB_L2T_IX(x) ((x) << S_TCB_L2T_IX) 108f7917c00SJeff Kirsher 109f7917c00SJeff Kirsher void t3_l2e_free(struct l2t_data *d, struct l2t_entry *e); 110f7917c00SJeff Kirsher void t3_l2t_update(struct t3cdev *dev, struct neighbour *neigh); 111f7917c00SJeff Kirsher struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh, 112f7917c00SJeff Kirsher struct net_device *dev); 113f7917c00SJeff Kirsher int t3_l2t_send_slow(struct t3cdev *dev, struct sk_buff *skb, 114f7917c00SJeff Kirsher struct l2t_entry *e); 115f7917c00SJeff Kirsher void t3_l2t_send_event(struct t3cdev *dev, struct l2t_entry *e); 116f7917c00SJeff Kirsher struct l2t_data *t3_init_l2t(unsigned int l2t_capacity); 117f7917c00SJeff Kirsher void t3_free_l2t(struct l2t_data *d); 118f7917c00SJeff Kirsher 119f7917c00SJeff Kirsher int cxgb3_ofld_send(struct t3cdev *dev, struct sk_buff *skb); 120f7917c00SJeff Kirsher 121f7917c00SJeff Kirsher static inline int l2t_send(struct t3cdev *dev, struct sk_buff *skb, 122f7917c00SJeff Kirsher struct l2t_entry *e) 123f7917c00SJeff Kirsher { 124f7917c00SJeff Kirsher if (likely(e->state == L2T_STATE_VALID)) 125f7917c00SJeff Kirsher return cxgb3_ofld_send(dev, skb); 126f7917c00SJeff Kirsher return t3_l2t_send_slow(dev, skb, e); 127f7917c00SJeff Kirsher } 128f7917c00SJeff Kirsher 129f7917c00SJeff Kirsher static inline void l2t_release(struct l2t_data *d, struct l2t_entry *e) 130f7917c00SJeff Kirsher { 131f7917c00SJeff Kirsher if (atomic_dec_and_test(&e->refcnt)) 132f7917c00SJeff Kirsher t3_l2e_free(d, e); 133f7917c00SJeff Kirsher } 134f7917c00SJeff Kirsher 135f7917c00SJeff Kirsher static inline void l2t_hold(struct l2t_data *d, struct l2t_entry *e) 136f7917c00SJeff Kirsher { 137f7917c00SJeff Kirsher if (atomic_add_return(1, &e->refcnt) == 1) /* 0 -> 1 transition */ 138f7917c00SJeff Kirsher atomic_dec(&d->nfree); 139f7917c00SJeff Kirsher } 140f7917c00SJeff Kirsher 141f7917c00SJeff Kirsher #endif 142