/*** * * rtmac_disc.c * * rtmac - real-time networking media access control subsystem * Copyright (C) 2002 Marc Kleine-Budde , * 2003, 2004 Jan Kiszka * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * */ #include #include #include #include #include #include #include #include #include static DEFINE_MUTEX(disc_list_lock); static LIST_HEAD(disc_list); /*** * rtmac_disc_attach * * @rtdev attaches a discipline to a device * @disc discipline to attach * * 0 success * -EBUSY other discipline active * -ENOMEM could not allocate memory * * Note: must be called with rtdev->nrt_lock acquired */ int rtmac_disc_attach(struct rtnet_device *rtdev, struct rtmac_disc *disc) { int ret; struct rtmac_priv *priv; RTNET_ASSERT(rtdev != NULL, return -EINVAL;); RTNET_ASSERT(disc != NULL, return -EINVAL;); RTNET_ASSERT(disc->attach != NULL, return -EINVAL;); if (rtdev->mac_disc) { printk("RTmac: another discipline for rtdev '%s' active.\n", rtdev->name); return -EBUSY; } if (rtdev->flags & IFF_LOOPBACK) return -EINVAL; if (!try_module_get(disc->owner)) return -EIDRM; if (!rtdev_reference(rtdev)) { ret = -EIDRM; goto err_module_put; } /* alloc memory */ priv = kmalloc(sizeof(struct rtmac_priv) + disc->priv_size, GFP_KERNEL); if (!priv) { printk("RTmac: kmalloc returned NULL for rtmac!\n"); return -ENOMEM; } priv->orig_start_xmit = rtdev->start_xmit; /* call attach function of discipline */ ret = disc->attach(rtdev, priv->disc_priv); if (ret < 0) goto err_kfree_priv; /* now attach RTmac to device */ rtdev->mac_disc = disc; rtdev->mac_priv = priv; rtdev->start_xmit = disc->rt_packet_tx; if (disc->get_mtu) rtdev->get_mtu = disc->get_mtu; rtdev->mac_detach = rtmac_disc_detach; /* create the VNIC */ ret = rtmac_vnic_add(rtdev, disc->vnic_xmit); if (ret < 0) { printk("RTmac: Warning, VNIC creation failed for rtdev %s.\n", rtdev->name); goto err_disc_detach; } return 0; err_disc_detach: disc->detach(rtdev, priv->disc_priv); err_kfree_priv: kfree(priv); rtdev_dereference(rtdev); err_module_put: module_put(disc->owner); return ret; } /*** * rtmac_disc_detach * * @rtdev detaches a discipline from a device * * 0 success * -1 discipline has no detach function * -EINVAL called with rtdev=NULL * -ENODEV no discipline active on dev * * Note: must be called with rtdev->nrt_lock acquired */ int rtmac_disc_detach(struct rtnet_device *rtdev) { int ret; struct rtmac_disc *disc; struct rtmac_priv *priv; RTNET_ASSERT(rtdev != NULL, return -EINVAL;); disc = rtdev->mac_disc; if (!disc) return -ENODEV; RTNET_ASSERT(disc->detach != NULL, return -EINVAL;); priv = rtdev->mac_priv; RTNET_ASSERT(priv != NULL, return -EINVAL;); ret = rtmac_vnic_unregister(rtdev); if (ret < 0) return ret; /* call release function of discipline */ ret = disc->detach(rtdev, priv->disc_priv); if (ret < 0) return ret; rtmac_vnic_cleanup(rtdev); /* restore start_xmit and get_mtu */ rtdev->start_xmit = priv->orig_start_xmit; rtdev->get_mtu = rt_hard_mtu; /* remove pointers from rtdev */ rtdev->mac_disc = NULL; rtdev->mac_priv = NULL; rtdev->mac_detach = NULL; rtdev_dereference(rtdev); kfree(priv); module_put(disc->owner); return 0; } static struct rtmac_disc *rtmac_get_disc_by_name(const char *name) { struct list_head *disc; mutex_lock(&disc_list_lock); list_for_each (disc, &disc_list) { if (strcmp(((struct rtmac_disc *)disc)->name, name) == 0) { mutex_unlock(&disc_list_lock); return (struct rtmac_disc *)disc; } } mutex_unlock(&disc_list_lock); return NULL; } int __rtmac_disc_register(struct rtmac_disc *disc, struct module *module) { int ret; RTNET_ASSERT(disc != NULL, return -EINVAL;); RTNET_ASSERT(disc->name != NULL, return -EINVAL;); RTNET_ASSERT(disc->rt_packet_tx != NULL, return -EINVAL;); RTNET_ASSERT(disc->nrt_packet_tx != NULL, return -EINVAL;); RTNET_ASSERT(disc->attach != NULL, return -EINVAL;); RTNET_ASSERT(disc->detach != NULL, return -EINVAL;); disc->owner = module; if (rtmac_get_disc_by_name(disc->name) != NULL) { printk("RTmac: discipline '%s' already registered!\n", disc->name); return -EBUSY; } ret = rtnet_register_ioctls(&disc->ioctls); if (ret < 0) return ret; #ifdef CONFIG_XENO_OPT_VFILE ret = rtmac_disc_proc_register(disc); if (ret < 0) { rtnet_unregister_ioctls(&disc->ioctls); return ret; } #endif /* CONFIG_XENO_OPT_VFILE */ mutex_lock(&disc_list_lock); list_add(&disc->list, &disc_list); mutex_unlock(&disc_list_lock); return 0; } void rtmac_disc_deregister(struct rtmac_disc *disc) { RTNET_ASSERT(disc != NULL, return;); mutex_lock(&disc_list_lock); list_del(&disc->list); mutex_unlock(&disc_list_lock); rtnet_unregister_ioctls(&disc->ioctls); #ifdef CONFIG_XENO_OPT_VFILE rtmac_disc_proc_unregister(disc); #endif /* CONFIG_XENO_OPT_VFILE */ } #ifdef CONFIG_XENO_OPT_VFILE int rtnet_rtmac_disciplines_show(struct xnvfile_regular_iterator *it, void *d) { struct rtmac_disc *disc; int err; err = mutex_lock_interruptible(&disc_list_lock); if (err < 0) return err; xnvfile_printf(it, "Name\t\tID\n"); list_for_each_entry (disc, &disc_list, list) xnvfile_printf(it, "%-15s %04X\n", disc->name, ntohs(disc->disc_type)); mutex_unlock(&disc_list_lock); return 0; } #endif /* CONFIG_XENO_OPT_VFILE */