Minor changes

This commit is contained in:
Ondrej Zajicek (work) 2015-10-17 14:36:53 +02:00
parent b5e76398de
commit acb04cfdc5
2 changed files with 36 additions and 21 deletions

View file

@ -507,19 +507,25 @@ void rta_show(struct cli *, rta *, ea_list *);
void rta_set_recursive_next_hop(rtable *dep, rta *a, rtable *tab, ip_addr *gw, ip_addr *ll);
/*
* rta_set_recursive_next_hop() acquires hostentry from hostcache and
* fills rta->hostentry field. New hostentry has zero use
* count. Cached rta locks its hostentry (increases its use count),
* uncached rta does not lock it. Hostentry with zero use count is
* removed asynchronously during host cache update, therefore it is
* safe to hold such hostentry temorarily. Hostentry holds a lock for
* a 'source' rta, mainly to share multipath nexthops. There is no
* need to hold a lock for hostentry->dep table, because that table
* contains routes responsible for that hostentry, and therefore is
* non-empty if given hostentry has non-zero use count. The protocol
* responsible for routes with recursive next hops should also hold a
* lock for a table governing that routes (argument tab to
* rta_set_recursive_next_hop()).
* rta_set_recursive_next_hop() acquires hostentry from hostcache and fills
* rta->hostentry field. New hostentry has zero use count. Cached rta locks its
* hostentry (increases its use count), uncached rta does not lock it. Hostentry
* with zero use count is removed asynchronously during host cache update,
* therefore it is safe to hold such hostentry temorarily. Hostentry holds a
* lock for a 'source' rta, mainly to share multipath nexthops.
*
* There is no need to hold a lock for hostentry->dep table, because that table
* contains routes responsible for that hostentry, and therefore is non-empty if
* given hostentry has non-zero use count. If the hostentry has zero use count,
* the entry is removed before dep is referenced.
*
* The protocol responsible for routes with recursive next hops should hold a
* lock for a 'source' table governing that routes (argument tab to
* rta_set_recursive_next_hop()), because its routes reference hostentries
* (through rta) related to the governing table. When all such routes are
* removed, rtas are immediately removed achieving zero uc. Then the 'source'
* table lock could be immediately released, although hostentries may still
* exist - they will be freed together with the 'source' table.
*/
static inline void rt_lock_hostentry(struct hostentry *he) { if (he) he->uc++; }

View file

@ -239,6 +239,16 @@ nl_parse_attrs(struct rtattr *a, struct rtattr **k, int ksize)
return 1;
}
static inline ip4_addr rta_get_u32(struct rtattr *a)
{ return *(u32 *) RTA_DATA(a); }
static inline ip4_addr rta_get_ip4(struct rtattr *a)
{ return ip4_ntoh(*(ip4_addr *) RTA_DATA(a)); }
static inline ip6_addr rta_get_ip6(struct rtattr *a)
{ return ip6_ntoh(*(ip6_addr *) RTA_DATA(a)); }
struct rtattr *
nl_add_attr(struct nlmsghdr *h, uint bufsize, uint code, const void *data, uint dlen)
{
@ -420,7 +430,7 @@ nl_parse_metrics(struct rtattr *hdr, u32 *metrics, int max)
return -1;
metrics[0] |= 1 << a->rta_type;
metrics[a->rta_type] = *(u32 *)RTA_DATA(a);
metrics[a->rta_type] = rta_get_u32(a);
}
if (len > 0)
@ -456,7 +466,7 @@ nl_parse_link(struct nlmsghdr *h, int scan)
return;
}
name = RTA_DATA(a[IFLA_IFNAME]);
memcpy(&mtu, RTA_DATA(a[IFLA_MTU]), sizeof(u32));
mtu = rta_get_u32(a[IFLA_MTU]);
ifi = if_find_by_index(i->ifi_index);
if (!new)
@ -831,7 +841,7 @@ nl_parse_route(struct nlmsghdr *h, int scan)
}
if (a[RTA_OIF])
memcpy(&oif, RTA_DATA(a[RTA_OIF]), sizeof(oif));
oif = rta_get_u32(a[RTA_OIF]);
p = nl_table_map[i->rtm_table]; /* Do we know this table? */
DBG("KRT: Got %I/%d, type=%d, oif=%d, table=%d, prid=%d, proto=%s\n", dst, i->rtm_dst_len, i->rtm_type, oif, i->rtm_table, i->rtm_protocol, p ? p->p.name : "(none)");
@ -965,11 +975,10 @@ nl_parse_route(struct nlmsghdr *h, int scan)
e->u.krt.src = src;
e->u.krt.proto = i->rtm_protocol;
e->u.krt.type = i->rtm_type;
e->u.krt.metric = 0;
if (a[RTA_PRIORITY])
memcpy(&e->u.krt.metric, RTA_DATA(a[RTA_PRIORITY]), sizeof(e->u.krt.metric));
else
e->u.krt.metric = 0;
e->u.krt.metric = rta_get_u32(a[RTA_PRIORITY]);
if (a[RTA_PREFSRC])
{
@ -1000,7 +1009,7 @@ nl_parse_route(struct nlmsghdr *h, int scan)
ea->attrs[0].id = EA_KRT_REALM;
ea->attrs[0].flags = 0;
ea->attrs[0].type = EAF_TYPE_INT;
memcpy(&ea->attrs[0].u.data, RTA_DATA(a[RTA_FLOW]), 4);
ea->attrs[0].u.data = rta_get_u32(a[RTA_FLOW]);
}
if (a[RTA_METRICS])