drivers/xen/sfc_netback/accel.c

   1 /****************************************************************************
   2  * Solarflare driver for Xen network acceleration
   3  *
   4  * Copyright 2006-2008: Solarflare Communications Inc,
   5  *                      9501 Jeronimo Road, Suite 250,
   6  *                      Irvine, CA 92618, USA
   7  *
   8  * Maintained by Solarflare Communications <linux-xen-drivers@solarflare.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License version 2 as published
  12  * by the Free Software Foundation, incorporated herein by reference.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  22  ****************************************************************************
  23  */
  24
  25 #include "accel.h"
  26 #include "accel_msg_iface.h"
  27 #include "accel_solarflare.h"
  28
  29 #include <linux/notifier.h>
  30
  31 #ifdef EFX_GCOV
  32 #include "gcov.h"
  33 #endif
  34
  35 static int netback_accel_netdev_event(struct notifier_block *nb,
  36                                       unsigned long event, void *ptr)
  37 {
  38         struct net_device *net_dev = (struct net_device *)ptr;
  39         struct netback_accel *bend;
  40
  41         if ((event == NETDEV_UP) ||
  42             (event == NETDEV_DOWN) ||
  43             (event == NETDEV_CHANGE)) {
  44                 mutex_lock(&bend_list_mutex);
  45                 bend = bend_list;
  46                 while (bend != NULL) {
  47                         mutex_lock(&bend->bend_mutex);
  48                         /*
  49                          * This happens when the shared pages have
  50                          * been unmapped, but the bend not yet removed
  51                          * from list
  52                          */
  53                         if (bend->shared_page == NULL)
  54                                 goto next;
  55
  56                         if (bend->net_dev->ifindex == net_dev->ifindex) {
  57                                 int ok;
  58                                 if (event == NETDEV_CHANGE)
  59                                         ok = (netif_carrier_ok(net_dev) &&
  60                                               (net_dev->flags & IFF_UP));
  61                                 else
  62                                         ok = (netif_carrier_ok(net_dev) &&
  63                                               (event == NETDEV_UP));
  64                                 netback_accel_set_interface_state(bend, ok);
  65                         }
  66
  67                 next:
  68                         mutex_unlock(&bend->bend_mutex);
  69                         bend = bend->next_bend;
  70                 }
  71                 mutex_unlock(&bend_list_mutex);
  72         }
  73
  74         return NOTIFY_DONE;
  75 }
  76
  77
  78 static struct notifier_block netback_accel_netdev_notifier = {
  79         .notifier_call = netback_accel_netdev_event,
  80 };
  81
  82
  83 unsigned sfc_netback_max_pages = NETBACK_ACCEL_DEFAULT_MAX_BUF_PAGES;
  84 module_param_named(max_pages, sfc_netback_max_pages, uint, 0644);
  85 MODULE_PARM_DESC(max_pages,
  86                  "The number of buffer pages to enforce on each guest");
  87
  88 /* Initialise subsystems need for the accelerated fast path */
  89 static int __init netback_accel_init(void)
  90 {
  91         int rc = 0;
  92
  93 #ifdef EFX_GCOV
  94         gcov_provider_init(THIS_MODULE);
  95 #endif
  96
  97         rc = netback_accel_init_fwd();
  98         if (rc != 0)
  99                 goto fail0;
 100
 101         netback_accel_debugfs_init();
 102
 103         rc = netback_accel_sf_init();
 104         if (rc != 0)
 105                 goto fail1;
 106
 107         rc = register_netdevice_notifier
 108                 (&netback_accel_netdev_notifier);
 109         if (rc != 0)
 110                 goto fail2;
 111
 112         return 0;
 113
 114  fail2:
 115         netback_accel_sf_shutdown();
 116  fail1:
 117         netback_accel_debugfs_fini();
 118         netback_accel_shutdown_fwd();
 119  fail0:
 120 #ifdef EFX_GCOV
 121         gcov_provider_fini(THIS_MODULE);
 122 #endif
 123         return rc;
 124 }
 125
 126 module_init(netback_accel_init);
 127
 128 static void __exit netback_accel_exit(void)
 129 {
 130         unregister_netdevice_notifier(&netback_accel_netdev_notifier);
 131
 132         netback_accel_sf_shutdown();
 133
 134         netback_accel_shutdown_bends();
 135
 136         netback_accel_debugfs_fini();
 137
 138         netback_accel_shutdown_fwd();
 139
 140 #ifdef EFX_GCOV
 141         gcov_provider_fini(THIS_MODULE);
 142 #endif
 143 }
 144
 145 module_exit(netback_accel_exit);
 146
 147 MODULE_LICENSE("GPL");