diff options
Diffstat (limited to 'sys/net')
| -rw-r--r-- | sys/net/if.c | 66 |
1 files changed, 56 insertions, 10 deletions
diff --git a/sys/net/if.c b/sys/net/if.c index 17f2265aab5..81d4efaea69 100644 --- a/sys/net/if.c +++ b/sys/net/if.c @@ -1,4 +1,4 @@ -/* $OpenBSD: if.c,v 1.659 2022/07/14 11:03:15 mvs Exp $ */ +/* $OpenBSD: if.c,v 1.660 2022/07/29 08:23:40 visa Exp $ */ /* $NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $ */ /* @@ -217,9 +217,12 @@ struct if_idxmap { unsigned int serial; unsigned int count; struct srp map; + struct rwlock lock; + unsigned char *usedidx; /* bitmap of indices in use */ }; void if_idxmap_init(unsigned int); +void if_idxmap_alloc(struct ifnet *); void if_idxmap_insert(struct ifnet *); void if_idxmap_remove(struct ifnet *); @@ -273,7 +276,9 @@ ifinit(void) static struct if_idxmap if_idxmap = { 0, 0, - SRP_INITIALIZER() + SRP_INITIALIZER(), + RWLOCK_INITIALIZER("idxmaplk"), + NULL, }; struct srp_gc if_ifp_gc = SRP_GC_INITIALIZER(if_ifp_dtor, NULL); @@ -298,12 +303,15 @@ if_idxmap_init(unsigned int limit) for (i = 0; i < limit; i++) srp_init(&map[i]); + if_idxmap.usedidx = malloc(howmany(limit, NBBY), + M_IFADDR, M_WAITOK | M_ZERO); + /* this is called early so there's nothing to race with */ srp_update_locked(&if_map_gc, &if_idxmap.map, if_map); } void -if_idxmap_insert(struct ifnet *ifp) +if_idxmap_alloc(struct ifnet *ifp) { struct if_map *if_map; struct srp *map; @@ -311,10 +319,9 @@ if_idxmap_insert(struct ifnet *ifp) refcnt_init(&ifp->if_refcnt); - /* the kernel lock guarantees serialised modifications to if_idxmap */ - KERNEL_ASSERT_LOCKED(); + rw_enter_write(&if_idxmap.lock); - if (++if_idxmap.count > USHRT_MAX) + if (++if_idxmap.count >= USHRT_MAX) panic("too many interfaces"); if_map = srp_get_locked(&if_idxmap.map); @@ -327,6 +334,7 @@ if_idxmap_insert(struct ifnet *ifp) struct srp *nmap; unsigned int nlimit; struct ifnet *nifp; + unsigned char *nusedidx; nlimit = if_map->limit * 2; nif_map = malloc(sizeof(*nif_map) + nlimit * sizeof(*nmap), @@ -348,6 +356,14 @@ if_idxmap_insert(struct ifnet *ifp) i++; } + nusedidx = malloc(howmany(nlimit, NBBY), + M_IFADDR, M_WAITOK | M_ZERO); + memcpy(nusedidx, if_idxmap.usedidx, + howmany(if_map->limit, NBBY)); + free(if_idxmap.usedidx, M_IFADDR, + howmany(if_map->limit, NBBY)); + if_idxmap.usedidx = nusedidx; + srp_update_locked(&if_map_gc, &if_idxmap.map, nif_map); if_map = nif_map; map = nmap; @@ -355,15 +371,39 @@ if_idxmap_insert(struct ifnet *ifp) /* pick the next free index */ for (i = 0; i < USHRT_MAX; i++) { - if (index != 0 && srp_get_locked(&map[index]) == NULL) + if (index != 0 && isclr(if_idxmap.usedidx, index)) break; index = if_idxmap.serial++ & USHRT_MAX; } + KASSERT(index != 0 && index < if_map->limit); + KASSERT(isclr(if_idxmap.usedidx, index)); - /* commit */ + setbit(if_idxmap.usedidx, index); ifp->if_index = index; + + rw_exit_write(&if_idxmap.lock); +} + +void +if_idxmap_insert(struct ifnet *ifp) +{ + struct if_map *if_map; + struct srp *map; + unsigned int index = ifp->if_index; + + rw_enter_write(&if_idxmap.lock); + + if_map = srp_get_locked(&if_idxmap.map); + map = (struct srp *)(if_map + 1); + + KASSERT(index != 0 && index < if_map->limit); + KASSERT(isset(if_idxmap.usedidx, index)); + + /* commit */ srp_update_locked(&if_ifp_gc, &map[index], if_ref(ifp)); + + rw_exit_write(&if_idxmap.lock); } void @@ -375,8 +415,7 @@ if_idxmap_remove(struct ifnet *ifp) index = ifp->if_index; - /* the kernel lock guarantees serialised modifications to if_idxmap */ - KERNEL_ASSERT_LOCKED(); + rw_enter_write(&if_idxmap.lock); if_map = srp_get_locked(&if_idxmap.map); KASSERT(index < if_map->limit); @@ -386,7 +425,12 @@ if_idxmap_remove(struct ifnet *ifp) srp_update_locked(&if_ifp_gc, &map[index], NULL); if_idxmap.count--; + + KASSERT(isset(if_idxmap.usedidx, index)); + clrbit(if_idxmap.usedidx, index); /* end of if_idxmap modifications */ + + rw_exit_write(&if_idxmap.lock); } void @@ -607,6 +651,8 @@ if_attach_common(struct ifnet *ifp) "%s: if_qstart not set with MPSAFE set", ifp->if_xname); } + if_idxmap_alloc(ifp); + ifq_init(&ifp->if_snd, ifp, 0); ifp->if_snd.ifq_ifqs[0] = &ifp->if_snd; |