/* * Copyright (c) 2003-2008 Chelsio, Inc. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #ifndef _CHELSIO_L2T_H #define _CHELSIO_L2T_H #include <linux/spinlock.h> #include "t3cdev.h" #include <linux/atomic.h> enum { L2T_STATE_VALID, /* entry is up to date */ L2T_STATE_STALE, /* entry may be used but needs revalidation */ L2T_STATE_RESOLVING, /* entry needs address resolution */ L2T_STATE_UNUSED /* entry not in use */ }; struct neighbour; struct sk_buff; /* * Each L2T entry plays multiple roles. First of all, it keeps state for the * corresponding entry of the HW L2 table and maintains a queue of offload * packets awaiting address resolution. Second, it is a node of a hash table * chain, where the nodes of the chain are linked together through their next * pointer. Finally, each node is a bucket of a hash table, pointing to the * first element in its chain through its first pointer. */ struct l2t_entry { u16 state; /* entry state */ u16 idx; /* entry index */ u32 addr; /* dest IP address */ int ifindex; /* neighbor's net_device's ifindex */ u16 smt_idx; /* SMT index */ u16 vlan; /* VLAN TCI (id: bits 0-11, prio: 13-15 */ struct neighbour *neigh; /* associated neighbour */ struct l2t_entry *first; /* start of hash chain */ struct l2t_entry *next; /* next l2t_entry on chain */ struct sk_buff_head arpq; /* queue of packets awaiting resolution */ spinlock_t lock; atomic_t refcnt; /* entry reference count */ u8 dmac[6]; /* neighbour's MAC address */ }; struct l2t_data { unsigned int nentries; /* number of entries */ struct l2t_entry *rover; /* starting point for next allocation */ atomic_t nfree; /* number of free entries */ rwlock_t lock; struct l2t_entry l2tab[0]; struct rcu_head rcu_head; /* to handle rcu cleanup */ }; typedef void (*arp_failure_handler_func)(struct t3cdev * dev, struct sk_buff * skb); /* * Callback stored in an skb to handle address resolution failure. */ struct l2t_skb_cb { arp_failure_handler_func arp_failure_handler; }; #define L2T_SKB_CB(skb) ((struct l2t_skb_cb *)(skb)->cb) static inline void set_arp_failure_handler(struct sk_buff *skb, arp_failure_handler_func hnd) { L2T_SKB_CB(skb)->arp_failure_handler = hnd; } /* * Getting to the L2 data from an offload device. */ #define L2DATA(cdev) (rcu_dereference((cdev)->l2opt)) #define W_TCB_L2T_IX 0 #define S_TCB_L2T_IX 7 #define M_TCB_L2T_IX 0x7ffULL #define V_TCB_L2T_IX(x) ((x) << S_TCB_L2T_IX) void t3_l2e_free(struct l2t_data *d, struct l2t_entry *e); void t3_l2t_update(struct t3cdev *dev, struct neighbour *neigh); struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct dst_entry *dst, struct net_device *dev); int t3_l2t_send_slow(struct t3cdev *dev, struct sk_buff *skb, struct l2t_entry *e); void t3_l2t_send_event(struct t3cdev *dev, struct l2t_entry *e); struct l2t_data *t3_init_l2t(unsigned int l2t_capacity); void t3_free_l2t(struct l2t_data *d); int cxgb3_ofld_send(struct t3cdev *dev, struct sk_buff *skb); static inline int l2t_send(struct t3cdev *dev, struct sk_buff *skb, struct l2t_entry *e) { if (likely(e->state == L2T_STATE_VALID)) return cxgb3_ofld_send(dev, skb); return t3_l2t_send_slow(dev, skb, e); } static inline void l2t_release(struct t3cdev *t, struct l2t_entry *e) { struct l2t_data *d; rcu_read_lock(); d = L2DATA(t); if (atomic_dec_and_test(&e->refcnt) && d) t3_l2e_free(d, e); rcu_read_unlock(); } static inline void l2t_hold(struct l2t_data *d, struct l2t_entry *e) { if (d && atomic_add_return(1, &e->refcnt) == 1) /* 0 -> 1 transition */ atomic_dec(&d->nfree); } #endif