drivers/net/ethernet/chelsio/cxgb4/l2t.h

   1 /*
   2  * This file is part of the Chelsio T4 Ethernet driver for Linux.
   3  *
   4  * Copyright (c) 2003-2010 Chelsio Communications, Inc. All rights reserved.
   5  *
   6  * This software is available to you under a choice of one of two
   7  * licenses.  You may choose to be licensed under the terms of the GNU
   8  * General Public License (GPL) Version 2, available from the file
   9  * COPYING in the main directory of this source tree, or the
  10  * OpenIB.org BSD license below:
  11  *
  12  *     Redistribution and use in source and binary forms, with or
  13  *     without modification, are permitted provided that the following
  14  *     conditions are met:
  15  *
  16  *      - Redistributions of source code must retain the above
  17  *        copyright notice, this list of conditions and the following
  18  *        disclaimer.
  19  *
  20  *      - Redistributions in binary form must reproduce the above
  21  *        copyright notice, this list of conditions and the following
  22  *        disclaimer in the documentation and/or other materials
  23  *        provided with the distribution.
  24  *
  25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  32  * SOFTWARE.
  33  */
  34
  35 #ifndef __CXGB4_L2T_H
  36 #define __CXGB4_L2T_H
  37
  38 #include <linux/spinlock.h>
  39 #include <linux/if_ether.h>
  40 #include <linux/atomic.h>
  41
  42 struct adapter;
  43 struct l2t_data;
  44 struct neighbour;
  45 struct net_device;
  46 struct file_operations;
  47 struct cpl_l2t_write_rpl;
  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  */
  57 struct l2t_entry {
  58         u16 state;                  /* entry state */
  59         u16 idx;                    /* entry index */
  60         u32 addr[4];                /* next hop IP or IPv6 address */
  61         int ifindex;                /* neighbor's net_device's ifindex */
  62         struct neighbour *neigh;    /* associated neighbour */
  63         struct l2t_entry *first;    /* start of hash chain */
  64         struct l2t_entry *next;     /* next l2t_entry on chain */
  65         struct sk_buff *arpq_head;  /* queue of packets awaiting resolution */
  66         struct sk_buff *arpq_tail;
  67         spinlock_t lock;
  68         atomic_t refcnt;            /* entry reference count */
  69         u16 hash;                   /* hash bucket the entry is on */
  70         u16 vlan;                   /* VLAN TCI (id: bits 0-11, prio: 13-15 */
  71         u8 v6;                      /* whether entry is for IPv6 */
  72         u8 lport;                   /* associated offload logical interface */
  73         u8 dmac[ETH_ALEN];          /* neighbour's MAC address */
  74 };
  75
  76 typedef void (*arp_err_handler_t)(void *handle, struct sk_buff *skb);
  77
  78 /*
  79  * Callback stored in an skb to handle address resolution failure.
  80  */
  81 struct l2t_skb_cb {
  82         void *handle;
  83         arp_err_handler_t arp_err_handler;
  84 };
  85
  86 #define L2T_SKB_CB(skb) ((struct l2t_skb_cb *)(skb)->cb)
  87
  88 static inline void t4_set_arp_err_handler(struct sk_buff *skb, void *handle,
  89                                           arp_err_handler_t handler)
  90 {
  91         L2T_SKB_CB(skb)->handle = handle;
  92         L2T_SKB_CB(skb)->arp_err_handler = handler;
  93 }
  94
  95 void cxgb4_l2t_release(struct l2t_entry *e);
  96 int cxgb4_l2t_send(struct net_device *dev, struct sk_buff *skb,
  97                    struct l2t_entry *e);
  98 struct l2t_entry *cxgb4_l2t_get(struct l2t_data *d, struct neighbour *neigh,
  99                                 const struct net_device *physdev,
 100                                 unsigned int priority);
 101
 102 void t4_l2t_update(struct adapter *adap, struct neighbour *neigh);
 103 struct l2t_data *t4_init_l2t(void);
 104 void do_l2t_write_rpl(struct adapter *p, const struct cpl_l2t_write_rpl *rpl);
 105
 106 extern const struct file_operations t4_l2t_fops;
 107 #endif  /* __CXGB4_L2T_H */