--- /dev/null
+/*
+ * 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
Code Review / kvmfornfv.git / blobdiff