sys/dev/pci/cxgb_l2t.h

   1 /**************************************************************************
   2
   3 Copyright (c) 2007, Chelsio Inc.
   4 All rights reserved.
   5
   6 Redistribution and use in source and binary forms, with or without
   7 modification, are permitted provided that the following conditions are met:
   8
   9  1. Redistributions of source code must retain the above copyright notice,
  10     this list of conditions and the following disclaimer.
  11
  12  2. Neither the name of the Chelsio Corporation nor the names of its
  13     contributors may be used to endorse or promote products derived from
  14     this software without specific prior written permission.
  15
  16 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  17 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  20 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  21 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  22 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  23 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  24 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  25 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  26 POSSIBILITY OF SUCH DAMAGE.
  27
  28 $FreeBSD: src/sys/dev/cxgb/cxgb_l2t.h,v 1.2 2007/08/17 05:57:03 kmacy Exp $
  29
  30 ***************************************************************************/
  31 #ifndef _CHELSIO_L2T_H
  32 #define _CHELSIO_L2T_H
  33
  34 #ifdef __FreeBSD__
  35 #include <dev/cxgb/ulp/toecore/toedev.h>
  36 #endif
  37 #include <sys/lock.h>
  38
  39 #ifdef __FreeBSD__
  40 #if __FreeBSD_version > 700000
  41 #include <sys/rwlock.h>
  42 #else
  43 #define rwlock mtx
  44 #define rw_wlock(x) mtx_lock((x))
  45 #define rw_wunlock(x) mtx_unlock((x))
  46 #define rw_rlock(x) mtx_lock((x))
  47 #define rw_runlock(x) mtx_unlock((x))
  48 #define rw_init(x, str) mtx_init((x), (str), NULL, MTX_DEF)
  49 #define rw_destroy(x) mtx_destroy((x))
  50 #endif
  51 #endif
  52 #ifdef __NetBSD__
  53 #define rwlock mtx
  54 #define rw_wlock(x) mtx_lock((x))
  55 #define rw_wunlock(x) mtx_unlock((x))
  56 #define rw_rlock(x) mtx_lock((x))
  57 #define rw_runlock(x) mtx_unlock((x))
  58 #define rw_init(x, str) mtx_init((x), (str), NULL, MTX_DEF)
  59 #define rw_destroy(x) mtx_destroy((x))
  60 #endif
  61
  62 enum {
  63     L2T_STATE_VALID,      /* entry is up to date */
  64     L2T_STATE_STALE,      /* entry may be used but needs revalidation */
  65     L2T_STATE_RESOLVING,  /* entry needs address resolution */
  66     L2T_STATE_UNUSED      /* entry not in use */
  67 };
  68
  69 /*
  70  * Each L2T entry plays multiple roles.  First of all, it keeps state for the
  71  * corresponding entry of the HW L2 table and maintains a queue of offload
  72  * packets awaiting address resolution.  Second, it is a node of a hash table
  73  * chain, where the nodes of the chain are linked together through their next
  74  * pointer.  Finally, each node is a bucket of a hash table, pointing to the
  75  * first element in its chain through its first pointer.
  76  */
  77 struct l2t_entry {
  78     uint16_t state;               /* entry state */
  79     uint16_t idx;                 /* entry index */
  80     uint32_t addr;                /* dest IP address */
  81     int ifindex;                  /* neighbor's net_device's ifindex */
  82     uint16_t smt_idx;             /* SMT index */
  83     uint16_t vlan;                /* VLAN TCI (id: bits 0-11, prio: 13-15 */
  84     struct rtentry *neigh;        /* associated neighbour */
  85     struct l2t_entry *first;      /* start of hash chain */
  86     struct l2t_entry *next;       /* next l2t_entry on chain */
  87     struct mbuf *arpq_head;       /* queue of packets awaiting resolution */
  88     struct mbuf *arpq_tail;
  89     struct mtx lock;
  90     volatile uint32_t refcnt;     /* entry reference count */
  91     uint8_t dmac[6];              /* neighbour's MAC address */
  92 #ifndef NETEVENT
  93 #ifdef CONFIG_CHELSIO_T3_MODULE
  94     struct timer_list update_timer;
  95 #ifdef __FreeBSD__
  96     struct toedev *tdev;
  97 #endif
  98 #endif
  99 #endif
 100 };
 101
 102 struct l2t_data {
 103     unsigned int nentries;      /* number of entries */
 104     struct l2t_entry *rover;    /* starting point for next allocation */
 105     volatile uint32_t nfree;    /* number of free entries */
 106     struct rwlock lock;
 107     struct l2t_entry l2tab[0];
 108 };
 109
 110 typedef void (*arp_failure_handler_func)(struct toedev *dev,
 111                      struct mbuf *m);
 112
 113 /*
 114  * Callback stored in an skb to handle address resolution failure.
 115  */
 116 struct l2t_mbuf_cb {
 117     arp_failure_handler_func arp_failure_handler;
 118 };
 119
 120 /*
 121  * XXX
 122  */
 123 #define L2T_MBUF_CB(skb) ((struct l2t_mbuf_cb *)(skb)->cb)
 124
 125
 126 static __inline void set_arp_failure_handler(struct mbuf *m,
 127                        arp_failure_handler_func hnd)
 128 {
 129 #if 0
 130     L2T_SKB_CB(skb)->arp_failure_handler = hnd;
 131 #endif
 132     panic("implement me");
 133 }
 134
 135 /*
 136  * Getting to the L2 data from an offload device.
 137  */
 138 #define L2DATA(dev) ((dev)->l2opt)
 139
 140 void t3_l2e_free(struct l2t_data *d, struct l2t_entry *e);
 141 void t3_l2t_update(struct toedev *dev, struct rtentry *ifp);
 142 struct l2t_entry *t3_l2t_get(struct toedev *dev, struct rtentry *neigh,
 143                  unsigned int smt_idx);
 144 int t3_l2t_send_slow(struct toedev *dev, struct mbuf *m,
 145              struct l2t_entry *e);
 146 void t3_l2t_send_event(struct toedev *dev, struct l2t_entry *e);
 147 struct l2t_data *t3_init_l2t(unsigned int l2t_capacity);
 148 void t3_free_l2t(struct l2t_data *d);
 149
 150 #ifdef CONFIG_PROC_FS
 151 int t3_l2t_proc_setup(struct proc_dir_entry *dir, struct l2t_data *d);
 152 void t3_l2t_proc_free(struct proc_dir_entry *dir);
 153 #else
 154 #define l2t_proc_setup(dir, d) 0
 155 #define l2t_proc_free(dir)
 156 #endif
 157
 158 int cxgb_ofld_send(struct toedev *dev, struct mbuf *m);
 159
 160 static inline int l2t_send(struct toedev *dev, struct mbuf *m,
 161                struct l2t_entry *e)
 162 {
 163     if (__predict_true(e->state == L2T_STATE_VALID))
 164         return cxgb_ofld_send(dev, m);
 165     return t3_l2t_send_slow(dev, m, e);
 166 }
 167
 168 static inline void l2t_release(struct l2t_data *d, struct l2t_entry *e)
 169 {
 170     if (atomic_fetchadd_int(&e->refcnt, -1) == 1)
 171         t3_l2e_free(d, e);
 172 }
 173
 174 static inline void l2t_hold(struct l2t_data *d, struct l2t_entry *e)
 175 {
 176     if (atomic_fetchadd_int(&e->refcnt, 1) == 1)  /* 0 -> 1 transition */
 177         atomic_add_int(&d->nfree, 1);
 178 }
 179
 180 #endif