diff options
Diffstat (limited to 'kernel/drivers/net/ethernet/chelsio/cxgb3/l2t.h')
| -rw-r--r-- | kernel/drivers/net/ethernet/chelsio/cxgb3/l2t.h | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/kernel/drivers/net/ethernet/chelsio/cxgb3/l2t.h b/kernel/drivers/net/ethernet/chelsio/cxgb3/l2t.h new file mode 100644 index 000000000..8cffcdfd5 --- /dev/null +++ b/kernel/drivers/net/ethernet/chelsio/cxgb3/l2t.h @@ -0,0 +1,149 @@ +/* + * 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, const void *daddr); +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 |