Revision 35bf49e054214a0c7d3b0a0f8606f753f3f6ae96 authored by Lu Baolu on 23 August 2022, 06:15:57 UTC, committed by Joerg Roedel on 07 September 2022, 13:14:57 UTC
With CONFIG_INTEL_IOMMU_DEBUGFS enabled, below lockdep splat are seen
when an I/O fault occurs on a machine with an Intel IOMMU in it.

 DMAR: DRHD: handling fault status reg 3
 DMAR: [DMA Write NO_PASID] Request device [00:1a.0] fault addr 0x0
       [fault reason 0x05] PTE Write access is not set
 DMAR: Dump dmar0 table entries for IOVA 0x0
 DMAR: root entry: 0x0000000127f42001
 DMAR: context entry: hi 0x0000000000001502, low 0x000000012d8ab001
 ================================
 WARNING: inconsistent lock state
 5.20.0-0.rc0.20220812git7ebfc85e2cd7.10.fc38.x86_64 #1 Not tainted
 --------------------------------
 inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
 rngd/1006 [HC1[1]:SC0[0]:HE0:SE1] takes:
 ff177021416f2d78 (&k->k_lock){?.+.}-{2:2}, at: klist_next+0x1b/0x160
 {HARDIRQ-ON-W} state was registered at:
   lock_acquire+0xce/0x2d0
   _raw_spin_lock+0x33/0x80
   klist_add_tail+0x46/0x80
   bus_add_device+0xee/0x150
   device_add+0x39d/0x9a0
   add_memory_block+0x108/0x1d0
   memory_dev_init+0xe1/0x117
   driver_init+0x43/0x4d
   kernel_init_freeable+0x1c2/0x2cc
   kernel_init+0x16/0x140
   ret_from_fork+0x1f/0x30
 irq event stamp: 7812
 hardirqs last  enabled at (7811): [<ffffffff85000e86>] asm_sysvec_apic_timer_interrupt+0x16/0x20
 hardirqs last disabled at (7812): [<ffffffff84f16894>] irqentry_enter+0x54/0x60
 softirqs last  enabled at (7794): [<ffffffff840ff669>] __irq_exit_rcu+0xf9/0x170
 softirqs last disabled at (7787): [<ffffffff840ff669>] __irq_exit_rcu+0xf9/0x170

The klist iterator functions using spin_*lock_irq*() but the klist
insertion functions using spin_*lock(), combined with the Intel DMAR
IOMMU driver iterating over klists from atomic (hardirq) context, where
pci_get_domain_bus_and_slot() calls into bus_find_device() which iterates
over klists.

As currently there's no plan to fix the klist to make it safe to use in
atomic context, this fixes the lockdep splat by avoid calling
pci_get_domain_bus_and_slot() in the hardirq context.

Fixes: 8ac0b64b9735 ("iommu/vt-d: Use pci_get_domain_bus_and_slot() in pgtable_walk()")
Reported-by: Lennert Buytenhek <buytenh@wantstofly.org>
Link: https://lore.kernel.org/linux-iommu/Yvo2dfpEh%2FWC+Wrr@wantstofly.org/
Link: https://lore.kernel.org/linux-iommu/YvyBdPwrTuHHbn5X@wantstofly.org/
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20220819015949.4795-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
1 parent a349ffc
Raw File
rose_route.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
 * Copyright (C) Terry Dawson VK2KTJ (terry@animats.net)
 */
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/slab.h>
#include <net/ax25.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <net/arp.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/tcp_states.h>
#include <linux/uaccess.h>
#include <linux/fcntl.h>
#include <linux/termios.h>	/* For TIOCINQ/OUTQ */
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/notifier.h>
#include <linux/init.h>
#include <net/rose.h>
#include <linux/seq_file.h>
#include <linux/export.h>

static unsigned int rose_neigh_no = 1;

static struct rose_node  *rose_node_list;
static DEFINE_SPINLOCK(rose_node_list_lock);
static struct rose_neigh *rose_neigh_list;
static DEFINE_SPINLOCK(rose_neigh_list_lock);
static struct rose_route *rose_route_list;
static DEFINE_SPINLOCK(rose_route_list_lock);

struct rose_neigh *rose_loopback_neigh;

/*
 *	Add a new route to a node, and in the process add the node and the
 *	neighbour if it is new.
 */
static int __must_check rose_add_node(struct rose_route_struct *rose_route,
	struct net_device *dev)
{
	struct rose_node  *rose_node, *rose_tmpn, *rose_tmpp;
	struct rose_neigh *rose_neigh;
	int i, res = 0;

	spin_lock_bh(&rose_node_list_lock);
	spin_lock_bh(&rose_neigh_list_lock);

	rose_node = rose_node_list;
	while (rose_node != NULL) {
		if ((rose_node->mask == rose_route->mask) &&
		    (rosecmpm(&rose_route->address, &rose_node->address,
			      rose_route->mask) == 0))
			break;
		rose_node = rose_node->next;
	}

	if (rose_node != NULL && rose_node->loopback) {
		res = -EINVAL;
		goto out;
	}

	rose_neigh = rose_neigh_list;
	while (rose_neigh != NULL) {
		if (ax25cmp(&rose_route->neighbour,
			    &rose_neigh->callsign) == 0 &&
		    rose_neigh->dev == dev)
			break;
		rose_neigh = rose_neigh->next;
	}

	if (rose_neigh == NULL) {
		rose_neigh = kmalloc(sizeof(*rose_neigh), GFP_ATOMIC);
		if (rose_neigh == NULL) {
			res = -ENOMEM;
			goto out;
		}

		rose_neigh->callsign  = rose_route->neighbour;
		rose_neigh->digipeat  = NULL;
		rose_neigh->ax25      = NULL;
		rose_neigh->dev       = dev;
		rose_neigh->count     = 0;
		rose_neigh->use       = 0;
		rose_neigh->dce_mode  = 0;
		rose_neigh->loopback  = 0;
		rose_neigh->number    = rose_neigh_no++;
		rose_neigh->restarted = 0;

		skb_queue_head_init(&rose_neigh->queue);

		timer_setup(&rose_neigh->ftimer, NULL, 0);
		timer_setup(&rose_neigh->t0timer, NULL, 0);

		if (rose_route->ndigis != 0) {
			rose_neigh->digipeat =
				kmalloc(sizeof(ax25_digi), GFP_ATOMIC);
			if (rose_neigh->digipeat == NULL) {
				kfree(rose_neigh);
				res = -ENOMEM;
				goto out;
			}

			rose_neigh->digipeat->ndigi      = rose_route->ndigis;
			rose_neigh->digipeat->lastrepeat = -1;

			for (i = 0; i < rose_route->ndigis; i++) {
				rose_neigh->digipeat->calls[i]    =
					rose_route->digipeaters[i];
				rose_neigh->digipeat->repeated[i] = 0;
			}
		}

		rose_neigh->next = rose_neigh_list;
		rose_neigh_list  = rose_neigh;
	}

	/*
	 * This is a new node to be inserted into the list. Find where it needs
	 * to be inserted into the list, and insert it. We want to be sure
	 * to order the list in descending order of mask size to ensure that
	 * later when we are searching this list the first match will be the
	 * best match.
	 */
	if (rose_node == NULL) {
		rose_tmpn = rose_node_list;
		rose_tmpp = NULL;

		while (rose_tmpn != NULL) {
			if (rose_tmpn->mask > rose_route->mask) {
				rose_tmpp = rose_tmpn;
				rose_tmpn = rose_tmpn->next;
			} else {
				break;
			}
		}

		/* create new node */
		rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC);
		if (rose_node == NULL) {
			res = -ENOMEM;
			goto out;
		}

		rose_node->address      = rose_route->address;
		rose_node->mask         = rose_route->mask;
		rose_node->count        = 1;
		rose_node->loopback     = 0;
		rose_node->neighbour[0] = rose_neigh;

		if (rose_tmpn == NULL) {
			if (rose_tmpp == NULL) {	/* Empty list */
				rose_node_list  = rose_node;
				rose_node->next = NULL;
			} else {
				rose_tmpp->next = rose_node;
				rose_node->next = NULL;
			}
		} else {
			if (rose_tmpp == NULL) {	/* 1st node */
				rose_node->next = rose_node_list;
				rose_node_list  = rose_node;
			} else {
				rose_tmpp->next = rose_node;
				rose_node->next = rose_tmpn;
			}
		}
		rose_neigh->count++;

		goto out;
	}

	/* We have space, slot it in */
	if (rose_node->count < 3) {
		rose_node->neighbour[rose_node->count] = rose_neigh;
		rose_node->count++;
		rose_neigh->count++;
	}

out:
	spin_unlock_bh(&rose_neigh_list_lock);
	spin_unlock_bh(&rose_node_list_lock);

	return res;
}

/*
 * Caller is holding rose_node_list_lock.
 */
static void rose_remove_node(struct rose_node *rose_node)
{
	struct rose_node *s;

	if ((s = rose_node_list) == rose_node) {
		rose_node_list = rose_node->next;
		kfree(rose_node);
		return;
	}

	while (s != NULL && s->next != NULL) {
		if (s->next == rose_node) {
			s->next = rose_node->next;
			kfree(rose_node);
			return;
		}

		s = s->next;
	}
}

/*
 * Caller is holding rose_neigh_list_lock.
 */
static void rose_remove_neigh(struct rose_neigh *rose_neigh)
{
	struct rose_neigh *s;

	del_timer_sync(&rose_neigh->ftimer);
	del_timer_sync(&rose_neigh->t0timer);

	skb_queue_purge(&rose_neigh->queue);

	if ((s = rose_neigh_list) == rose_neigh) {
		rose_neigh_list = rose_neigh->next;
		if (rose_neigh->ax25)
			ax25_cb_put(rose_neigh->ax25);
		kfree(rose_neigh->digipeat);
		kfree(rose_neigh);
		return;
	}

	while (s != NULL && s->next != NULL) {
		if (s->next == rose_neigh) {
			s->next = rose_neigh->next;
			if (rose_neigh->ax25)
				ax25_cb_put(rose_neigh->ax25);
			kfree(rose_neigh->digipeat);
			kfree(rose_neigh);
			return;
		}

		s = s->next;
	}
}

/*
 * Caller is holding rose_route_list_lock.
 */
static void rose_remove_route(struct rose_route *rose_route)
{
	struct rose_route *s;

	if (rose_route->neigh1 != NULL)
		rose_route->neigh1->use--;

	if (rose_route->neigh2 != NULL)
		rose_route->neigh2->use--;

	if ((s = rose_route_list) == rose_route) {
		rose_route_list = rose_route->next;
		kfree(rose_route);
		return;
	}

	while (s != NULL && s->next != NULL) {
		if (s->next == rose_route) {
			s->next = rose_route->next;
			kfree(rose_route);
			return;
		}

		s = s->next;
	}
}

/*
 *	"Delete" a node. Strictly speaking remove a route to a node. The node
 *	is only deleted if no routes are left to it.
 */
static int rose_del_node(struct rose_route_struct *rose_route,
	struct net_device *dev)
{
	struct rose_node  *rose_node;
	struct rose_neigh *rose_neigh;
	int i, err = 0;

	spin_lock_bh(&rose_node_list_lock);
	spin_lock_bh(&rose_neigh_list_lock);

	rose_node = rose_node_list;
	while (rose_node != NULL) {
		if ((rose_node->mask == rose_route->mask) &&
		    (rosecmpm(&rose_route->address, &rose_node->address,
			      rose_route->mask) == 0))
			break;
		rose_node = rose_node->next;
	}

	if (rose_node == NULL || rose_node->loopback) {
		err = -EINVAL;
		goto out;
	}

	rose_neigh = rose_neigh_list;
	while (rose_neigh != NULL) {
		if (ax25cmp(&rose_route->neighbour,
			    &rose_neigh->callsign) == 0 &&
		    rose_neigh->dev == dev)
			break;
		rose_neigh = rose_neigh->next;
	}

	if (rose_neigh == NULL) {
		err = -EINVAL;
		goto out;
	}

	for (i = 0; i < rose_node->count; i++) {
		if (rose_node->neighbour[i] == rose_neigh) {
			rose_neigh->count--;

			if (rose_neigh->count == 0 && rose_neigh->use == 0)
				rose_remove_neigh(rose_neigh);

			rose_node->count--;

			if (rose_node->count == 0) {
				rose_remove_node(rose_node);
			} else {
				switch (i) {
				case 0:
					rose_node->neighbour[0] =
						rose_node->neighbour[1];
					fallthrough;
				case 1:
					rose_node->neighbour[1] =
						rose_node->neighbour[2];
					break;
				case 2:
					break;
				}
			}
			goto out;
		}
	}
	err = -EINVAL;

out:
	spin_unlock_bh(&rose_neigh_list_lock);
	spin_unlock_bh(&rose_node_list_lock);

	return err;
}

/*
 *	Add the loopback neighbour.
 */
void rose_add_loopback_neigh(void)
{
	struct rose_neigh *sn;

	rose_loopback_neigh = kmalloc(sizeof(struct rose_neigh), GFP_KERNEL);
	if (!rose_loopback_neigh)
		return;
	sn = rose_loopback_neigh;

	sn->callsign  = null_ax25_address;
	sn->digipeat  = NULL;
	sn->ax25      = NULL;
	sn->dev       = NULL;
	sn->count     = 0;
	sn->use       = 0;
	sn->dce_mode  = 1;
	sn->loopback  = 1;
	sn->number    = rose_neigh_no++;
	sn->restarted = 1;

	skb_queue_head_init(&sn->queue);

	timer_setup(&sn->ftimer, NULL, 0);
	timer_setup(&sn->t0timer, NULL, 0);

	spin_lock_bh(&rose_neigh_list_lock);
	sn->next = rose_neigh_list;
	rose_neigh_list           = sn;
	spin_unlock_bh(&rose_neigh_list_lock);
}

/*
 *	Add a loopback node.
 */
int rose_add_loopback_node(const rose_address *address)
{
	struct rose_node *rose_node;
	int err = 0;

	spin_lock_bh(&rose_node_list_lock);

	rose_node = rose_node_list;
	while (rose_node != NULL) {
		if ((rose_node->mask == 10) &&
		     (rosecmpm(address, &rose_node->address, 10) == 0) &&
		     rose_node->loopback)
			break;
		rose_node = rose_node->next;
	}

	if (rose_node != NULL)
		goto out;

	if ((rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC)) == NULL) {
		err = -ENOMEM;
		goto out;
	}

	rose_node->address      = *address;
	rose_node->mask         = 10;
	rose_node->count        = 1;
	rose_node->loopback     = 1;
	rose_node->neighbour[0] = rose_loopback_neigh;

	/* Insert at the head of list. Address is always mask=10 */
	rose_node->next = rose_node_list;
	rose_node_list  = rose_node;

	rose_loopback_neigh->count++;

out:
	spin_unlock_bh(&rose_node_list_lock);

	return err;
}

/*
 *	Delete a loopback node.
 */
void rose_del_loopback_node(const rose_address *address)
{
	struct rose_node *rose_node;

	spin_lock_bh(&rose_node_list_lock);

	rose_node = rose_node_list;
	while (rose_node != NULL) {
		if ((rose_node->mask == 10) &&
		    (rosecmpm(address, &rose_node->address, 10) == 0) &&
		    rose_node->loopback)
			break;
		rose_node = rose_node->next;
	}

	if (rose_node == NULL)
		goto out;

	rose_remove_node(rose_node);

	rose_loopback_neigh->count--;

out:
	spin_unlock_bh(&rose_node_list_lock);
}

/*
 *	A device has been removed. Remove its routes and neighbours.
 */
void rose_rt_device_down(struct net_device *dev)
{
	struct rose_neigh *s, *rose_neigh;
	struct rose_node  *t, *rose_node;
	int i;

	spin_lock_bh(&rose_node_list_lock);
	spin_lock_bh(&rose_neigh_list_lock);
	rose_neigh = rose_neigh_list;
	while (rose_neigh != NULL) {
		s          = rose_neigh;
		rose_neigh = rose_neigh->next;

		if (s->dev != dev)
			continue;

		rose_node = rose_node_list;

		while (rose_node != NULL) {
			t         = rose_node;
			rose_node = rose_node->next;

			for (i = 0; i < t->count; i++) {
				if (t->neighbour[i] != s)
					continue;

				t->count--;

				switch (i) {
				case 0:
					t->neighbour[0] = t->neighbour[1];
					fallthrough;
				case 1:
					t->neighbour[1] = t->neighbour[2];
					break;
				case 2:
					break;
				}
			}

			if (t->count <= 0)
				rose_remove_node(t);
		}

		rose_remove_neigh(s);
	}
	spin_unlock_bh(&rose_neigh_list_lock);
	spin_unlock_bh(&rose_node_list_lock);
}

#if 0 /* Currently unused */
/*
 *	A device has been removed. Remove its links.
 */
void rose_route_device_down(struct net_device *dev)
{
	struct rose_route *s, *rose_route;

	spin_lock_bh(&rose_route_list_lock);
	rose_route = rose_route_list;
	while (rose_route != NULL) {
		s          = rose_route;
		rose_route = rose_route->next;

		if (s->neigh1->dev == dev || s->neigh2->dev == dev)
			rose_remove_route(s);
	}
	spin_unlock_bh(&rose_route_list_lock);
}
#endif

/*
 *	Clear all nodes and neighbours out, except for neighbours with
 *	active connections going through them.
 *  Do not clear loopback neighbour and nodes.
 */
static int rose_clear_routes(void)
{
	struct rose_neigh *s, *rose_neigh;
	struct rose_node  *t, *rose_node;

	spin_lock_bh(&rose_node_list_lock);
	spin_lock_bh(&rose_neigh_list_lock);

	rose_neigh = rose_neigh_list;
	rose_node  = rose_node_list;

	while (rose_node != NULL) {
		t         = rose_node;
		rose_node = rose_node->next;
		if (!t->loopback)
			rose_remove_node(t);
	}

	while (rose_neigh != NULL) {
		s          = rose_neigh;
		rose_neigh = rose_neigh->next;

		if (s->use == 0 && !s->loopback) {
			s->count = 0;
			rose_remove_neigh(s);
		}
	}

	spin_unlock_bh(&rose_neigh_list_lock);
	spin_unlock_bh(&rose_node_list_lock);

	return 0;
}

/*
 *	Check that the device given is a valid AX.25 interface that is "up".
 * 	called with RTNL
 */
static struct net_device *rose_ax25_dev_find(char *devname)
{
	struct net_device *dev;

	if ((dev = __dev_get_by_name(&init_net, devname)) == NULL)
		return NULL;

	if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
		return dev;

	return NULL;
}

/*
 *	Find the first active ROSE device, usually "rose0".
 */
struct net_device *rose_dev_first(void)
{
	struct net_device *dev, *first = NULL;

	rcu_read_lock();
	for_each_netdev_rcu(&init_net, dev) {
		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE)
			if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
				first = dev;
	}
	if (first)
		dev_hold(first);
	rcu_read_unlock();

	return first;
}

/*
 *	Find the ROSE device for the given address.
 */
struct net_device *rose_dev_get(rose_address *addr)
{
	struct net_device *dev;

	rcu_read_lock();
	for_each_netdev_rcu(&init_net, dev) {
		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
		    rosecmp(addr, (const rose_address *)dev->dev_addr) == 0) {
			dev_hold(dev);
			goto out;
		}
	}
	dev = NULL;
out:
	rcu_read_unlock();
	return dev;
}

static int rose_dev_exists(rose_address *addr)
{
	struct net_device *dev;

	rcu_read_lock();
	for_each_netdev_rcu(&init_net, dev) {
		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
		    rosecmp(addr, (const rose_address *)dev->dev_addr) == 0)
			goto out;
	}
	dev = NULL;
out:
	rcu_read_unlock();
	return dev != NULL;
}




struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
{
	struct rose_route *rose_route;

	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
		if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
		    (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
			return rose_route;

	return NULL;
}

/*
 *	Find a neighbour or a route given a ROSE address.
 */
struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
	unsigned char *diagnostic, int route_frame)
{
	struct rose_neigh *res = NULL;
	struct rose_node *node;
	int failed = 0;
	int i;

	if (!route_frame) spin_lock_bh(&rose_node_list_lock);
	for (node = rose_node_list; node != NULL; node = node->next) {
		if (rosecmpm(addr, &node->address, node->mask) == 0) {
			for (i = 0; i < node->count; i++) {
				if (node->neighbour[i]->restarted) {
					res = node->neighbour[i];
					goto out;
				}
			}
		}
	}
	if (!route_frame) { /* connect request */
		for (node = rose_node_list; node != NULL; node = node->next) {
			if (rosecmpm(addr, &node->address, node->mask) == 0) {
				for (i = 0; i < node->count; i++) {
					if (!rose_ftimer_running(node->neighbour[i])) {
						res = node->neighbour[i];
						goto out;
					}
					failed = 1;
				}
			}
		}
	}

	if (failed) {
		*cause      = ROSE_OUT_OF_ORDER;
		*diagnostic = 0;
	} else {
		*cause      = ROSE_NOT_OBTAINABLE;
		*diagnostic = 0;
	}

out:
	if (!route_frame) spin_unlock_bh(&rose_node_list_lock);
	return res;
}

/*
 *	Handle the ioctls that control the routing functions.
 */
int rose_rt_ioctl(unsigned int cmd, void __user *arg)
{
	struct rose_route_struct rose_route;
	struct net_device *dev;
	int err;

	switch (cmd) {
	case SIOCADDRT:
		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
			return -EFAULT;
		if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
			return -EINVAL;
		if (rose_dev_exists(&rose_route.address)) /* Can't add routes to ourself */
			return -EINVAL;
		if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
			return -EINVAL;
		if (rose_route.ndigis > AX25_MAX_DIGIS)
			return -EINVAL;
		err = rose_add_node(&rose_route, dev);
		return err;

	case SIOCDELRT:
		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
			return -EFAULT;
		if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
			return -EINVAL;
		err = rose_del_node(&rose_route, dev);
		return err;

	case SIOCRSCLRRT:
		return rose_clear_routes();

	default:
		return -EINVAL;
	}

	return 0;
}

static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
{
	struct rose_route *rose_route, *s;

	rose_neigh->restarted = 0;

	rose_stop_t0timer(rose_neigh);
	rose_start_ftimer(rose_neigh);

	skb_queue_purge(&rose_neigh->queue);

	spin_lock_bh(&rose_route_list_lock);

	rose_route = rose_route_list;

	while (rose_route != NULL) {
		if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
		    (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
		    (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
			s = rose_route->next;
			rose_remove_route(rose_route);
			rose_route = s;
			continue;
		}

		if (rose_route->neigh1 == rose_neigh) {
			rose_route->neigh1->use--;
			rose_route->neigh1 = NULL;
			rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
		}

		if (rose_route->neigh2 == rose_neigh) {
			rose_route->neigh2->use--;
			rose_route->neigh2 = NULL;
			rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
		}

		rose_route = rose_route->next;
	}
	spin_unlock_bh(&rose_route_list_lock);
}

/*
 * 	A level 2 link has timed out, therefore it appears to be a poor link,
 *	then don't use that neighbour until it is reset. Blow away all through
 *	routes and connections using this route.
 */
void rose_link_failed(ax25_cb *ax25, int reason)
{
	struct rose_neigh *rose_neigh;

	spin_lock_bh(&rose_neigh_list_lock);
	rose_neigh = rose_neigh_list;
	while (rose_neigh != NULL) {
		if (rose_neigh->ax25 == ax25)
			break;
		rose_neigh = rose_neigh->next;
	}

	if (rose_neigh != NULL) {
		rose_neigh->ax25 = NULL;
		ax25_cb_put(ax25);

		rose_del_route_by_neigh(rose_neigh);
		rose_kill_by_neigh(rose_neigh);
	}
	spin_unlock_bh(&rose_neigh_list_lock);
}

/*
 * 	A device has been "downed" remove its link status. Blow away all
 *	through routes and connections that use this device.
 */
void rose_link_device_down(struct net_device *dev)
{
	struct rose_neigh *rose_neigh;

	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
		if (rose_neigh->dev == dev) {
			rose_del_route_by_neigh(rose_neigh);
			rose_kill_by_neigh(rose_neigh);
		}
	}
}

/*
 *	Route a frame to an appropriate AX.25 connection.
 *	A NULL ax25_cb indicates an internally generated frame.
 */
int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
{
	struct rose_neigh *rose_neigh, *new_neigh;
	struct rose_route *rose_route;
	struct rose_facilities_struct facilities;
	rose_address *src_addr, *dest_addr;
	struct sock *sk;
	unsigned short frametype;
	unsigned int lci, new_lci;
	unsigned char cause, diagnostic;
	struct net_device *dev;
	int res = 0;
	char buf[11];

	if (skb->len < ROSE_MIN_LEN)
		return res;

	if (!ax25)
		return rose_loopback_queue(skb, NULL);

	frametype = skb->data[2];
	lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
	if (frametype == ROSE_CALL_REQUEST &&
	    (skb->len <= ROSE_CALL_REQ_FACILITIES_OFF ||
	     skb->data[ROSE_CALL_REQ_ADDR_LEN_OFF] !=
	     ROSE_CALL_REQ_ADDR_LEN_VAL))
		return res;
	src_addr  = (rose_address *)(skb->data + ROSE_CALL_REQ_SRC_ADDR_OFF);
	dest_addr = (rose_address *)(skb->data + ROSE_CALL_REQ_DEST_ADDR_OFF);

	spin_lock_bh(&rose_neigh_list_lock);
	spin_lock_bh(&rose_route_list_lock);

	rose_neigh = rose_neigh_list;
	while (rose_neigh != NULL) {
		if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 &&
		    ax25->ax25_dev->dev == rose_neigh->dev)
			break;
		rose_neigh = rose_neigh->next;
	}

	if (rose_neigh == NULL) {
		printk("rose_route : unknown neighbour or device %s\n",
		       ax2asc(buf, &ax25->dest_addr));
		goto out;
	}

	/*
	 *	Obviously the link is working, halt the ftimer.
	 */
	rose_stop_ftimer(rose_neigh);

	/*
	 *	LCI of zero is always for us, and its always a restart
	 * 	frame.
	 */
	if (lci == 0) {
		rose_link_rx_restart(skb, rose_neigh, frametype);
		goto out;
	}

	/*
	 *	Find an existing socket.
	 */
	if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
		if (frametype == ROSE_CALL_REQUEST) {
			struct rose_sock *rose = rose_sk(sk);

			/* Remove an existing unused socket */
			rose_clear_queues(sk);
			rose->cause	 = ROSE_NETWORK_CONGESTION;
			rose->diagnostic = 0;
			rose->neighbour->use--;
			rose->neighbour	 = NULL;
			rose->lci	 = 0;
			rose->state	 = ROSE_STATE_0;
			sk->sk_state	 = TCP_CLOSE;
			sk->sk_err	 = 0;
			sk->sk_shutdown	 |= SEND_SHUTDOWN;
			if (!sock_flag(sk, SOCK_DEAD)) {
				sk->sk_state_change(sk);
				sock_set_flag(sk, SOCK_DEAD);
			}
		}
		else {
			skb_reset_transport_header(skb);
			res = rose_process_rx_frame(sk, skb);
			goto out;
		}
	}

	/*
	 *	Is is a Call Request and is it for us ?
	 */
	if (frametype == ROSE_CALL_REQUEST)
		if ((dev = rose_dev_get(dest_addr)) != NULL) {
			res = rose_rx_call_request(skb, dev, rose_neigh, lci);
			dev_put(dev);
			goto out;
		}

	if (!sysctl_rose_routing_control) {
		rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 0);
		goto out;
	}

	/*
	 *	Route it to the next in line if we have an entry for it.
	 */
	rose_route = rose_route_list;
	while (rose_route != NULL) {
		if (rose_route->lci1 == lci &&
		    rose_route->neigh1 == rose_neigh) {
			if (frametype == ROSE_CALL_REQUEST) {
				/* F6FBB - Remove an existing unused route */
				rose_remove_route(rose_route);
				break;
			} else if (rose_route->neigh2 != NULL) {
				skb->data[0] &= 0xF0;
				skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
				skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
				rose_transmit_link(skb, rose_route->neigh2);
				if (frametype == ROSE_CLEAR_CONFIRMATION)
					rose_remove_route(rose_route);
				res = 1;
				goto out;
			} else {
				if (frametype == ROSE_CLEAR_CONFIRMATION)
					rose_remove_route(rose_route);
				goto out;
			}
		}
		if (rose_route->lci2 == lci &&
		    rose_route->neigh2 == rose_neigh) {
			if (frametype == ROSE_CALL_REQUEST) {
				/* F6FBB - Remove an existing unused route */
				rose_remove_route(rose_route);
				break;
			} else if (rose_route->neigh1 != NULL) {
				skb->data[0] &= 0xF0;
				skb->data[0] |= (rose_route->lci1 >> 8) & 0x0F;
				skb->data[1]  = (rose_route->lci1 >> 0) & 0xFF;
				rose_transmit_link(skb, rose_route->neigh1);
				if (frametype == ROSE_CLEAR_CONFIRMATION)
					rose_remove_route(rose_route);
				res = 1;
				goto out;
			} else {
				if (frametype == ROSE_CLEAR_CONFIRMATION)
					rose_remove_route(rose_route);
				goto out;
			}
		}
		rose_route = rose_route->next;
	}

	/*
	 *	We know that:
	 *	1. The frame isn't for us,
	 *	2. It isn't "owned" by any existing route.
	 */
	if (frametype != ROSE_CALL_REQUEST) {	/* XXX */
		res = 0;
		goto out;
	}

	memset(&facilities, 0x00, sizeof(struct rose_facilities_struct));

	if (!rose_parse_facilities(skb->data + ROSE_CALL_REQ_FACILITIES_OFF,
				   skb->len - ROSE_CALL_REQ_FACILITIES_OFF,
				   &facilities)) {
		rose_transmit_clear_request(rose_neigh, lci, ROSE_INVALID_FACILITY, 76);
		goto out;
	}

	/*
	 *	Check for routing loops.
	 */
	rose_route = rose_route_list;
	while (rose_route != NULL) {
		if (rose_route->rand == facilities.rand &&
		    rosecmp(src_addr, &rose_route->src_addr) == 0 &&
		    ax25cmp(&facilities.dest_call, &rose_route->src_call) == 0 &&
		    ax25cmp(&facilities.source_call, &rose_route->dest_call) == 0) {
			rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 120);
			goto out;
		}
		rose_route = rose_route->next;
	}

	if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic, 1)) == NULL) {
		rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
		goto out;
	}

	if ((new_lci = rose_new_lci(new_neigh)) == 0) {
		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 71);
		goto out;
	}

	if ((rose_route = kmalloc(sizeof(*rose_route), GFP_ATOMIC)) == NULL) {
		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 120);
		goto out;
	}

	rose_route->lci1      = lci;
	rose_route->src_addr  = *src_addr;
	rose_route->dest_addr = *dest_addr;
	rose_route->src_call  = facilities.dest_call;
	rose_route->dest_call = facilities.source_call;
	rose_route->rand      = facilities.rand;
	rose_route->neigh1    = rose_neigh;
	rose_route->lci2      = new_lci;
	rose_route->neigh2    = new_neigh;

	rose_route->neigh1->use++;
	rose_route->neigh2->use++;

	rose_route->next = rose_route_list;
	rose_route_list  = rose_route;

	skb->data[0] &= 0xF0;
	skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
	skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;

	rose_transmit_link(skb, rose_route->neigh2);
	res = 1;

out:
	spin_unlock_bh(&rose_route_list_lock);
	spin_unlock_bh(&rose_neigh_list_lock);

	return res;
}

#ifdef CONFIG_PROC_FS

static void *rose_node_start(struct seq_file *seq, loff_t *pos)
	__acquires(rose_node_list_lock)
{
	struct rose_node *rose_node;
	int i = 1;

	spin_lock_bh(&rose_node_list_lock);
	if (*pos == 0)
		return SEQ_START_TOKEN;

	for (rose_node = rose_node_list; rose_node && i < *pos;
	     rose_node = rose_node->next, ++i);

	return (i == *pos) ? rose_node : NULL;
}

static void *rose_node_next(struct seq_file *seq, void *v, loff_t *pos)
{
	++*pos;

	return (v == SEQ_START_TOKEN) ? rose_node_list
		: ((struct rose_node *)v)->next;
}

static void rose_node_stop(struct seq_file *seq, void *v)
	__releases(rose_node_list_lock)
{
	spin_unlock_bh(&rose_node_list_lock);
}

static int rose_node_show(struct seq_file *seq, void *v)
{
	char rsbuf[11];
	int i;

	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "address    mask n neigh neigh neigh\n");
	else {
		const struct rose_node *rose_node = v;
		seq_printf(seq, "%-10s %04d %d",
			   rose2asc(rsbuf, &rose_node->address),
			   rose_node->mask,
			   rose_node->count);

		for (i = 0; i < rose_node->count; i++)
			seq_printf(seq, " %05d", rose_node->neighbour[i]->number);

		seq_puts(seq, "\n");
	}
	return 0;
}

const struct seq_operations rose_node_seqops = {
	.start = rose_node_start,
	.next = rose_node_next,
	.stop = rose_node_stop,
	.show = rose_node_show,
};

static void *rose_neigh_start(struct seq_file *seq, loff_t *pos)
	__acquires(rose_neigh_list_lock)
{
	struct rose_neigh *rose_neigh;
	int i = 1;

	spin_lock_bh(&rose_neigh_list_lock);
	if (*pos == 0)
		return SEQ_START_TOKEN;

	for (rose_neigh = rose_neigh_list; rose_neigh && i < *pos;
	     rose_neigh = rose_neigh->next, ++i);

	return (i == *pos) ? rose_neigh : NULL;
}

static void *rose_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
{
	++*pos;

	return (v == SEQ_START_TOKEN) ? rose_neigh_list
		: ((struct rose_neigh *)v)->next;
}

static void rose_neigh_stop(struct seq_file *seq, void *v)
	__releases(rose_neigh_list_lock)
{
	spin_unlock_bh(&rose_neigh_list_lock);
}

static int rose_neigh_show(struct seq_file *seq, void *v)
{
	char buf[11];
	int i;

	if (v == SEQ_START_TOKEN)
		seq_puts(seq,
			 "addr  callsign  dev  count use mode restart  t0  tf digipeaters\n");
	else {
		struct rose_neigh *rose_neigh = v;

		/* if (!rose_neigh->loopback) { */
		seq_printf(seq, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3lu %3lu",
			   rose_neigh->number,
			   (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign),
			   rose_neigh->dev ? rose_neigh->dev->name : "???",
			   rose_neigh->count,
			   rose_neigh->use,
			   (rose_neigh->dce_mode) ? "DCE" : "DTE",
			   (rose_neigh->restarted) ? "yes" : "no",
			   ax25_display_timer(&rose_neigh->t0timer) / HZ,
			   ax25_display_timer(&rose_neigh->ftimer)  / HZ);

		if (rose_neigh->digipeat != NULL) {
			for (i = 0; i < rose_neigh->digipeat->ndigi; i++)
				seq_printf(seq, " %s", ax2asc(buf, &rose_neigh->digipeat->calls[i]));
		}

		seq_puts(seq, "\n");
	}
	return 0;
}


const struct seq_operations rose_neigh_seqops = {
	.start = rose_neigh_start,
	.next = rose_neigh_next,
	.stop = rose_neigh_stop,
	.show = rose_neigh_show,
};

static void *rose_route_start(struct seq_file *seq, loff_t *pos)
	__acquires(rose_route_list_lock)
{
	struct rose_route *rose_route;
	int i = 1;

	spin_lock_bh(&rose_route_list_lock);
	if (*pos == 0)
		return SEQ_START_TOKEN;

	for (rose_route = rose_route_list; rose_route && i < *pos;
	     rose_route = rose_route->next, ++i);

	return (i == *pos) ? rose_route : NULL;
}

static void *rose_route_next(struct seq_file *seq, void *v, loff_t *pos)
{
	++*pos;

	return (v == SEQ_START_TOKEN) ? rose_route_list
		: ((struct rose_route *)v)->next;
}

static void rose_route_stop(struct seq_file *seq, void *v)
	__releases(rose_route_list_lock)
{
	spin_unlock_bh(&rose_route_list_lock);
}

static int rose_route_show(struct seq_file *seq, void *v)
{
	char buf[11], rsbuf[11];

	if (v == SEQ_START_TOKEN)
		seq_puts(seq,
			 "lci  address     callsign   neigh  <-> lci  address     callsign   neigh\n");
	else {
		struct rose_route *rose_route = v;

		if (rose_route->neigh1)
			seq_printf(seq,
				   "%3.3X  %-10s  %-9s  %05d      ",
				   rose_route->lci1,
				   rose2asc(rsbuf, &rose_route->src_addr),
				   ax2asc(buf, &rose_route->src_call),
				   rose_route->neigh1->number);
		else
			seq_puts(seq,
				 "000  *           *          00000      ");

		if (rose_route->neigh2)
			seq_printf(seq,
				   "%3.3X  %-10s  %-9s  %05d\n",
				   rose_route->lci2,
				   rose2asc(rsbuf, &rose_route->dest_addr),
				   ax2asc(buf, &rose_route->dest_call),
				   rose_route->neigh2->number);
		 else
			 seq_puts(seq,
				  "000  *           *          00000\n");
		}
	return 0;
}

struct seq_operations rose_route_seqops = {
	.start = rose_route_start,
	.next = rose_route_next,
	.stop = rose_route_stop,
	.show = rose_route_show,
};
#endif /* CONFIG_PROC_FS */

/*
 *	Release all memory associated with ROSE routing structures.
 */
void __exit rose_rt_free(void)
{
	struct rose_neigh *s, *rose_neigh = rose_neigh_list;
	struct rose_node  *t, *rose_node  = rose_node_list;
	struct rose_route *u, *rose_route = rose_route_list;

	while (rose_neigh != NULL) {
		s          = rose_neigh;
		rose_neigh = rose_neigh->next;

		rose_remove_neigh(s);
	}

	while (rose_node != NULL) {
		t         = rose_node;
		rose_node = rose_node->next;

		rose_remove_node(t);
	}

	while (rose_route != NULL) {
		u          = rose_route;
		rose_route = rose_route->next;

		rose_remove_route(u);
	}
}
back to top