void dn_fib_release_info(struct dn_fib_info *fi)
{
spin_lock(&dn_fib_info_lock);
if (fi && --fi->fib_treeref == 0) {
if (fi->fib_next)
fi->fib_next->fib_prev = fi->fib_prev;
if (fi->fib_prev)
fi->fib_prev->fib_next = fi->fib_next;
if (fi == dn_fib_info_list)
dn_fib_info_list = fi->fib_next;
fi->fib_dead = 1;
dn_fib_info_put(fi);
}
spin_unlock(&dn_fib_info_lock);
}
static int dn_route_output_slow(struct dst_entry **pprt, const struct flowi *oldflp, int try_hard)
{
struct flowi fl = { .nl_u = { .dn_u =
{ .daddr = oldflp->fld_dst,
.saddr = oldflp->fld_src,
.scope = RT_SCOPE_UNIVERSE,
#ifdef CONFIG_DECNET_ROUTE_FWMARK
.fwmark = oldflp->fld_fwmark
#endif
} },
.iif = loopback_dev.ifindex,
.oif = oldflp->oif };
struct dn_route *rt = NULL;
struct net_device *dev_out = NULL;
struct neighbour *neigh = NULL;
unsigned hash;
unsigned flags = 0;
struct dn_fib_res res = { .fi = NULL, .type = RTN_UNICAST };
int err;
int free_res = 0;
__le16 gateway = 0;
if (decnet_debug_level & 16)
printk(KERN_DEBUG
"dn_route_output_slow: dst=%04x src=%04x mark=%d"
" iif=%d oif=%d\n", dn_ntohs(oldflp->fld_dst),
dn_ntohs(oldflp->fld_src),
oldflp->fld_fwmark, loopback_dev.ifindex, oldflp->oif);
/* If we have an output interface, verify its a DECnet device */
if (oldflp->oif) {
dev_out = dev_get_by_index(oldflp->oif);
err = -ENODEV;
if (dev_out && dev_out->dn_ptr == NULL) {
dev_put(dev_out);
dev_out = NULL;
}
if (dev_out == NULL)
goto out;
}
/* If we have a source address, verify that its a local address */
if (oldflp->fld_src) {
err = -EADDRNOTAVAIL;
if (dev_out) {
if (dn_dev_islocal(dev_out, oldflp->fld_src))
goto source_ok;
dev_put(dev_out);
goto out;
}
read_lock(&dev_base_lock);
for(dev_out = dev_base; dev_out; dev_out = dev_out->next) {
if (!dev_out->dn_ptr)
continue;
if (!dn_dev_islocal(dev_out, oldflp->fld_src))
continue;
if ((dev_out->flags & IFF_LOOPBACK) &&
oldflp->fld_dst &&
!dn_dev_islocal(dev_out, oldflp->fld_dst))
continue;
break;
}
read_unlock(&dev_base_lock);
if (dev_out == NULL)
goto out;
dev_hold(dev_out);
source_ok:
;
}
/* No destination? Assume its local */
if (!fl.fld_dst) {
fl.fld_dst = fl.fld_src;
err = -EADDRNOTAVAIL;
if (dev_out)
dev_put(dev_out);
dev_out = &loopback_dev;
dev_hold(dev_out);
if (!fl.fld_dst) {
fl.fld_dst =
fl.fld_src = dnet_select_source(dev_out, 0,
RT_SCOPE_HOST);
if (!fl.fld_dst)
goto out;
}
fl.oif = loopback_dev.ifindex;
res.type = RTN_LOCAL;
goto make_route;
}
if (decnet_debug_level & 16)
printk(KERN_DEBUG
"dn_route_output_slow: initial checks complete."
" dst=%o4x src=%04x oif=%d try_hard=%d\n",
dn_ntohs(fl.fld_dst), dn_ntohs(fl.fld_src),
fl.oif, try_hard);
/*
* N.B. If the kernel is compiled without router support then
* dn_fib_lookup() will evaluate to non-zero so this if () block
* will always be executed.
*/
err = -ESRCH;
if (try_hard || (err = dn_fib_lookup(&fl, &res)) != 0) {
struct dn_dev *dn_db;
if (err != -ESRCH)
goto out;
/*
* Here the fallback is basically the standard algorithm for
* routing in endnodes which is described in the DECnet routing
* docs
*
* If we are not trying hard, look in neighbour cache.
* The result is tested to ensure that if a specific output
* device/source address was requested, then we honour that
* here
*/
if (!try_hard) {
neigh = neigh_lookup_nodev(&dn_neigh_table, &fl.fld_dst);
if (neigh) {
if ((oldflp->oif &&
(neigh->dev->ifindex != oldflp->oif)) ||
(oldflp->fld_src &&
(!dn_dev_islocal(neigh->dev,
oldflp->fld_src)))) {
neigh_release(neigh);
neigh = NULL;
} else {
if (dev_out)
dev_put(dev_out);
if (dn_dev_islocal(neigh->dev, fl.fld_dst)) {
dev_out = &loopback_dev;
res.type = RTN_LOCAL;
} else {
dev_out = neigh->dev;
}
dev_hold(dev_out);
goto select_source;
}
}
}
/* Not there? Perhaps its a local address */
if (dev_out == NULL)
dev_out = dn_dev_get_default();
err = -ENODEV;
if (dev_out == NULL)
goto out;
dn_db = dev_out->dn_ptr;
/* Possible improvement - check all devices for local addr */
if (dn_dev_islocal(dev_out, fl.fld_dst)) {
dev_put(dev_out);
dev_out = &loopback_dev;
dev_hold(dev_out);
res.type = RTN_LOCAL;
goto select_source;
}
/* Not local either.... try sending it to the default router */
neigh = neigh_clone(dn_db->router);
BUG_ON(neigh && neigh->dev != dev_out);
/* Ok then, we assume its directly connected and move on */
select_source:
if (neigh)
gateway = ((struct dn_neigh *)neigh)->addr;
if (gateway == 0)
gateway = fl.fld_dst;
if (fl.fld_src == 0) {
fl.fld_src = dnet_select_source(dev_out, gateway,
res.type == RTN_LOCAL ?
RT_SCOPE_HOST :
RT_SCOPE_LINK);
if (fl.fld_src == 0 && res.type != RTN_LOCAL)
goto e_addr;
}
fl.oif = dev_out->ifindex;
goto make_route;
}
free_res = 1;
if (res.type == RTN_NAT)
goto e_inval;
if (res.type == RTN_LOCAL) {
if (!fl.fld_src)
fl.fld_src = fl.fld_dst;
if (dev_out)
dev_put(dev_out);
dev_out = &loopback_dev;
dev_hold(dev_out);
fl.oif = dev_out->ifindex;
if (res.fi)
dn_fib_info_put(res.fi);
res.fi = NULL;
goto make_route;
}
if (res.fi->fib_nhs > 1 && fl.oif == 0)
dn_fib_select_multipath(&fl, &res);
/*
* We could add some logic to deal with default routes here and
* get rid of some of the special casing above.
*/
if (!fl.fld_src)
fl.fld_src = DN_FIB_RES_PREFSRC(res);
if (dev_out)
dev_put(dev_out);
dev_out = DN_FIB_RES_DEV(res);
dev_hold(dev_out);
fl.oif = dev_out->ifindex;
gateway = DN_FIB_RES_GW(res);
make_route:
if (dev_out->flags & IFF_LOOPBACK)
flags |= RTCF_LOCAL;
rt = dst_alloc(&dn_dst_ops);
if (rt == NULL)
goto e_nobufs;
atomic_set(&rt->u.dst.__refcnt, 1);
rt->u.dst.flags = DST_HOST;
rt->fl.fld_src = oldflp->fld_src;
rt->fl.fld_dst = oldflp->fld_dst;
rt->fl.oif = oldflp->oif;
rt->fl.iif = 0;
#ifdef CONFIG_DECNET_ROUTE_FWMARK
rt->fl.fld_fwmark = oldflp->fld_fwmark;
#endif
rt->rt_saddr = fl.fld_src;
rt->rt_daddr = fl.fld_dst;
rt->rt_gateway = gateway ? gateway : fl.fld_dst;
rt->rt_local_src = fl.fld_src;
rt->rt_dst_map = fl.fld_dst;
rt->rt_src_map = fl.fld_src;
rt->u.dst.dev = dev_out;
dev_hold(dev_out);
rt->u.dst.neighbour = neigh;
neigh = NULL;
rt->u.dst.lastuse = jiffies;
rt->u.dst.output = dn_output;
rt->u.dst.input = dn_rt_bug;
rt->rt_flags = flags;
if (flags & RTCF_LOCAL)
rt->u.dst.input = dn_nsp_rx;
err = dn_rt_set_next_hop(rt, &res);
if (err)
goto e_neighbour;
hash = dn_hash(rt->fl.fld_src, rt->fl.fld_dst);
dn_insert_route(rt, hash, (struct dn_route **)pprt);
done:
if (neigh)
neigh_release(neigh);
if (free_res)
dn_fib_res_put(&res);
if (dev_out)
dev_put(dev_out);
out:
return err;
e_addr:
err = -EADDRNOTAVAIL;
goto done;
e_inval:
err = -EINVAL;
goto done;
e_nobufs:
err = -ENOBUFS;
goto done;
e_neighbour:
dst_free(&rt->u.dst);
goto e_nobufs;
}
