Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ]
Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  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 
 39 enum {
 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 
 46 struct neighbour;
 47 struct 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  */
 57 struct 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 
 73 struct 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 
 81 typedef 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  */
 87 struct 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 
 93 static 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 
109 void t3_l2e_free(struct l2t_data *d, struct l2t_entry *e);
110 void t3_l2t_update(struct t3cdev *dev, struct neighbour *neigh);
111 struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
112                              struct net_device *dev);
113 int t3_l2t_send_slow(struct t3cdev *dev, struct sk_buff *skb,
114                      struct l2t_entry *e);
115 void t3_l2t_send_event(struct t3cdev *dev, struct l2t_entry *e);
116 struct l2t_data *t3_init_l2t(unsigned int l2t_capacity);
117 void t3_free_l2t(struct l2t_data *d);
118 
119 int cxgb3_ofld_send(struct t3cdev *dev, struct sk_buff *skb);
120 
121 static 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 
129 static 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 
135 static 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 
  This page was automatically generated by the LXR engine.