Date: Sun, 7 Dec 2014 15:42:46 +0000 (UTC) From: "Alexander V. Chernikov" <melifaro@FreeBSD.org> To: src-committers@freebsd.org, svn-src-projects@freebsd.org Subject: svn commit: r275577 - in projects/routing/sys: net netinet netinet6 Message-ID: <201412071542.sB7FgkJ1063134@svn.freebsd.org>
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Author: melifaro Date: Sun Dec 7 15:42:46 2014 New Revision: 275577 URL: https://svnweb.freebsd.org/changeset/base/275577 Log: * Add llt_clear_entry() callback which is able to do all lle cleanup including unlinking/freeing * Relax locking in lltable_prefix_free_af/lltable_free * Do not pass @llt to lle free callback: it is always NULL now. * Unify arptimer/nd6_llinfo_timer: explicitly unlock lle avoiding unlock/lock sequinces * Do not pass unlocked lle to nd6_ns_output(): add nd6_llinfo_get_holdsrc() to retrieve preferred source address from lle hold queue and pass it instead of lle. * Finally, make nd6_create() create and return unlocked lle * Separate defrtr handling code from nd6_free(): use nd6_check_del_defrtr() to check if we need to keep entry instead of performing GC, use nd6_check_recalc_defrtr() to perform actual recalc on lle removal. * Move isRouter handling from nd6_cache_lladdr() to separate nd6_check_router() * Add initial code to maintain lle runtime flags in sync. Modified: projects/routing/sys/net/if_llatbl.c projects/routing/sys/net/if_llatbl.h projects/routing/sys/netinet/if_ether.c projects/routing/sys/netinet/if_ether.h projects/routing/sys/netinet/in.c projects/routing/sys/netinet/toecore.c projects/routing/sys/netinet6/in6.c projects/routing/sys/netinet6/nd6.c projects/routing/sys/netinet6/nd6.h projects/routing/sys/netinet6/nd6_nbr.c Modified: projects/routing/sys/net/if_llatbl.c ============================================================================== --- projects/routing/sys/net/if_llatbl.c Sun Dec 7 11:21:41 2014 (r275576) +++ projects/routing/sys/net/if_llatbl.c Sun Dec 7 15:42:46 2014 (r275577) @@ -254,17 +254,17 @@ lltable_free(struct lltable *llt) for (i = 0; i < LLTBL_HASHTBL_SIZE; i++) { LIST_FOREACH_SAFE(lle, &llt->lle_head[i], lle_next, next) { LLE_WLOCK(lle); - llt->llt_stop_timers(lle); LIST_INSERT_HEAD(&dchain, lle, lle_chain); } } IF_AFDATA_RUN_WLOCK(llt->llt_ifp); llentries_unlink(&dchain); IF_AFDATA_RUN_WUNLOCK(llt->llt_ifp); - LIST_FOREACH_SAFE(lle, &dchain, lle_chain, next) - llentry_free(lle); IF_AFDATA_CFG_WUNLOCK(llt->llt_ifp); + LIST_FOREACH_SAFE(lle, &dchain, lle_chain, next) + llt->llt_clear_entry(llt, lle); + free(llt, M_LLTABLE); } @@ -282,7 +282,6 @@ lltable_prefix_free_af(struct lltable *l LIST_FOREACH_SAFE(lle, &llt->lle_head[i], lle_next, next) { if (llt->llt_match_prefix(prefix, mask, flags, lle)) { LLE_WLOCK(lle); - llt->llt_stop_timers(lle); LIST_INSERT_HEAD(&dchain, lle, lle_chain); } } @@ -290,9 +289,10 @@ lltable_prefix_free_af(struct lltable *l IF_AFDATA_RUN_WLOCK(llt->llt_ifp); llentries_unlink(&dchain); IF_AFDATA_RUN_WUNLOCK(llt->llt_ifp); - LIST_FOREACH_SAFE(lle, &dchain, lle_chain, next) - llentry_free(lle); IF_AFDATA_CFG_WUNLOCK(llt->llt_ifp); + + LIST_FOREACH_SAFE(lle, &dchain, lle_chain, next) + llt->llt_clear_entry(llt, lle); } #if 0 Modified: projects/routing/sys/net/if_llatbl.h ============================================================================== --- projects/routing/sys/net/if_llatbl.h Sun Dec 7 11:21:41 2014 (r275576) +++ projects/routing/sys/net/if_llatbl.h Sun Dec 7 15:42:46 2014 (r275577) @@ -68,7 +68,7 @@ struct llentry { /* FIELDS PROTECTED BY LLE rwlock */ struct lltable *lle_tbl; struct llentries *lle_head; - void (*lle_free)(struct lltable *, struct llentry *); + void (*lle_free)(struct llentry *); struct mbuf *la_hold; int la_numheld; /* # of packets currently held */ time_t la_expire; @@ -117,7 +117,7 @@ struct llentry { #define LLE_FREE_LOCKED(lle) do { \ if ((lle)->lle_refcnt == 1) \ - (lle)->lle_free((lle)->lle_tbl, (lle)); \ + (lle)->lle_free((lle)); \ else { \ LLE_REMREF(lle); \ LLE_WUNLOCK(lle); \ @@ -158,7 +158,7 @@ typedef int (llt_dump_entry_t)(struct ll typedef uint32_t (llt_hash_t)(const struct llentry *); typedef int (llt_match_prefix_t)(const struct sockaddr *, const struct sockaddr *, u_int, struct llentry *); -typedef void (llt_stop_timers_t)(struct llentry *lle); +typedef void (llt_clear_entry_t)(struct lltable *, struct llentry *); struct lltable { SLIST_ENTRY(lltable) llt_link; @@ -172,7 +172,7 @@ struct lltable { llt_dump_entry_t *llt_dump_entry; llt_hash_t *llt_hash; llt_match_prefix_t *llt_match_prefix; - llt_stop_timers_t *llt_stop_timers; + llt_clear_entry_t *llt_clear_entry; }; MALLOC_DECLARE(M_LLTABLE); Modified: projects/routing/sys/netinet/if_ether.c ============================================================================== --- projects/routing/sys/netinet/if_ether.c Sun Dec 7 11:21:41 2014 (r275576) +++ projects/routing/sys/netinet/if_ether.c Sun Dec 7 15:42:46 2014 (r275577) @@ -182,43 +182,33 @@ static void arptimer(void *arg) { struct llentry *lle = (struct llentry *)arg; + struct lltable *llt; struct ifnet *ifp; - size_t pkts_dropped; - uint16_t la_flags; - int state; + int evt; if (lle->la_flags & LLE_STATIC) { + /* TODO: ensure we won't get here */ LLE_WUNLOCK(lle); return; } - if (lle->la_falgs & LLE_DELETED) { - /* XXX: Temporary */ + if (lle->la_flags & LLE_DELETED) { /* We have been deleted. Drop callref and return */ - if ((lle->la_flags & LLE_CALLOUTREF) != 0) { - LLE_REMREF(lle); - lle->la_flags &= ~LLE_CALLOUTREF; - } + KASSERT((lle->la_flags & LLE_CALLOUTREF) != 0, + ("arptimer was called without callout reference")); - pkts_dropped = llentry_free(lle); - ARPSTAT_ADD(dropped, pkts_dropped); + /* Assume the entry was already cleared */ + lle->la_flags &= ~LLE_CALLOUTREF; + LLE_FREE_LOCKED(lle); return; } - /* Unlink entry */ - IF_AFDATA_RUN_WLOCK(ifp); - llentry_unlink(lle); - IF_AFDATA_RUN_WUNLOCK(ifp); - - pkts_dropped = llentry_free(lle); - ARPSTAT_ADD(dropped, pkts_dropped); + llt = lle->lle_tbl; + ifp = llt->llt_ifp; - la_flags = lle->la_flags; - state = (la_flags & LLE_DELETED) ? ARP_LLINFO_DELETED : lle->ln_state; - ifp = lle->lle_tbl->llt_ifp; CURVNET_SET(ifp->if_vnet); - switch (state) { + switch (lle->ln_state) { case ARP_LLINFO_REACHABLE: /* @@ -234,6 +224,7 @@ arptimer(void *arg) lle->ln_state = ARP_LLINFO_VERIFY; callout_schedule(&lle->la_timer, hz * V_arpt_rexmit); LLE_WUNLOCK(lle); + CURVNET_RESTORE(); return; case ARP_LLINFO_VERIFY: if (lle->r_kick == 0 && lle->la_preempt > 0) { @@ -245,60 +236,78 @@ arptimer(void *arg) lle->r_kick = 1; callout_schedule(&lle->la_timer, hz * V_arpt_rexmit); LLE_WUNLOCK(lle); + CURVNET_RESTORE(); return; } /* Nothing happened. Reschedule if not too late */ if (lle->la_expire > time_uptime) { callout_schedule(&lle->la_timer, hz * V_arpt_rexmit); LLE_WUNLOCK(lle); + CURVNET_RESTORE(); return; } break; case ARP_LLINFO_INCOMPLETE: - case ARP_LLINFO_DELETED: break; } - if ((lle->la_flags & LLE_DELETED) == 0) { - int evt; + /* We have to delete entr */ + if (lle->la_flags & LLE_VALID) + evt = LLENTRY_EXPIRED; + else + evt = LLENTRY_TIMEDOUT; + EVENTHANDLER_INVOKE(lle_event, lle, evt); - if (lle->la_flags & LLE_VALID) - evt = LLENTRY_EXPIRED; - else - evt = LLENTRY_TIMEDOUT; - EVENTHANDLER_INVOKE(lle_event, lle, evt); - } + llt->llt_clear_entry(llt, lle); - callout_stop(&lle->la_timer); + ARPSTAT_INC(timeouts); - /* XXX: LOR avoidance. We still have ref on lle. */ - LLE_WUNLOCK(lle); - IF_AFDATA_CFG_WLOCK(ifp); - LLE_WLOCK(lle); + CURVNET_RESTORE(); +} - /* - * Note other thread could have removed given entry - * stopping callout and removing LLE reference. - */ - //llt->llt_stop_timers(lle); - if ((lle->la_flags & LLE_CALLOUTREF) != 0) { +/* + * Calback for lltable. + */ +void +arp_lltable_clear_entry(struct lltable *llt, struct llentry *lle) +{ + struct ifnet *ifp; + size_t pkts_dropped; + + LLE_WLOCK_ASSERT(lle); + KASSERT(llt != NULL, ("lltable is NULL")); + + /* Unlink entry from table if not already */ + if ((lle->la_flags & LLE_LINKED) != 0) { + + ifp = llt->llt_ifp; + /* + * Lock order needs to be maintained + */ + LLE_ADDREF(lle); + LLE_WUNLOCK(lle); + IF_AFDATA_CFG_WLOCK(ifp); + LLE_WLOCK(lle); LLE_REMREF(lle); - lle->la_flags &= ~LLE_CALLOUTREF; + + IF_AFDATA_RUN_WLOCK(ifp); + llentry_unlink(lle); + IF_AFDATA_RUN_WUNLOCK(ifp); + + IF_AFDATA_CFG_WUNLOCK(ifp); } - /* Unlink entry */ - IF_AFDATA_RUN_WLOCK(ifp); - llentry_unlink(lle); - IF_AFDATA_RUN_WUNLOCK(ifp); + /* cancel timer */ + if (callout_stop(&lle->la_timer) != 0) { + if ((lle->la_flags & LLE_CALLOUTREF) != 0) { + LLE_REMREF(lle); + lle->la_flags &= ~LLE_CALLOUTREF; + } + } + /* Finally, free entry */ pkts_dropped = llentry_free(lle); ARPSTAT_ADD(dropped, pkts_dropped); - - IF_AFDATA_CFG_WUNLOCK(ifp); - - ARPSTAT_INC(timeouts); - - CURVNET_RESTORE(); } /* Modified: projects/routing/sys/netinet/if_ether.h ============================================================================== --- projects/routing/sys/netinet/if_ether.h Sun Dec 7 11:21:41 2014 (r275576) +++ projects/routing/sys/netinet/if_ether.h Sun Dec 7 15:42:46 2014 (r275577) @@ -112,6 +112,7 @@ struct sockaddr_inarp { extern u_char ether_ipmulticast_min[ETHER_ADDR_LEN]; extern u_char ether_ipmulticast_max[ETHER_ADDR_LEN]; +struct lltable; struct llentry; struct ifaddr; @@ -124,6 +125,7 @@ void arprequest(struct ifnet *, const st void arp_ifinit(struct ifnet *, struct ifaddr *); void arp_ifinit2(struct ifnet *, struct ifaddr *, u_char *); void arp_ifscrub(struct ifnet *, uint32_t); +void arp_lltable_clear_entry(struct lltable *, struct llentry *); #endif #endif Modified: projects/routing/sys/netinet/in.c ============================================================================== --- projects/routing/sys/netinet/in.c Sun Dec 7 11:21:41 2014 (r275576) +++ projects/routing/sys/netinet/in.c Sun Dec 7 15:42:46 2014 (r275577) @@ -994,14 +994,15 @@ struct in_llentry { }; /* - * Deletes an address from the address table. + * Frees unlinked record. * This function is called by the timer functions * such as arptimer() and nd6_llinfo_timer(), and * the caller does the locking. */ static void -in_lltable_free(struct lltable *llt, struct llentry *lle) +in_lltable_free(struct llentry *lle) { + LLE_WUNLOCK(lle); LLE_LOCK_DESTROY(lle); free(lle, M_LLTABLE); @@ -1035,17 +1036,6 @@ in_lltable_new(const struct sockaddr *l3 return (&lle->base); } -static void -in_lltable_stop_timers(struct llentry *lle) -{ - - LLE_WLOCK_ASSERT(lle); - if (callout_stop(&lle->la_timer)) { - LLE_REMREF(lle); - lle->la_flags &= ~LLE_CALLOUTREF; - } -} - #define IN_ARE_MASKED_ADDR_EQUAL(d, a, m) ( \ (((ntohl((d)->sin_addr.s_addr) ^ (a)->sin_addr.s_addr) & (m)->sin_addr.s_addr)) == 0 ) @@ -1314,7 +1304,7 @@ in_domifattach(struct ifnet *ifp) llt->llt_delete = in_lltable_delete; llt->llt_dump_entry = in_lltable_dump_entry; llt->llt_hash = in_lltable_hash; - llt->llt_stop_timers = in_lltable_stop_timers; + llt->llt_clear_entry = arp_lltable_clear_entry; llt->llt_match_prefix = in_lltable_match_prefix; } ii->ii_llt = llt; Modified: projects/routing/sys/netinet/toecore.c ============================================================================== --- projects/routing/sys/netinet/toecore.c Sun Dec 7 11:21:41 2014 (r275576) +++ projects/routing/sys/netinet/toecore.c Sun Dec 7 15:42:46 2014 (r275577) @@ -37,6 +37,8 @@ __FBSDID("$FreeBSD$"); #include <sys/mbuf.h> #include <sys/module.h> #include <sys/types.h> +#include <sys/lock.h> +#include <sys/rmlock.h> #include <sys/sockopt.h> #include <sys/sysctl.h> #include <sys/socket.h> @@ -453,7 +455,7 @@ toe_route_redirect_event(void *arg __unu static int toe_nd6_resolve(struct ifnet *ifp, struct sockaddr *sa, uint8_t *lladdr) { - struct llentry *lle; + struct llentry *lle, *lle_tmp; struct sockaddr_in6 *sin6 = (void *)sa; int rc, flags = 0; @@ -462,19 +464,39 @@ restart: lle = lltable_lookup_lle(LLTABLE6(ifp), flags, sa); IF_AFDATA_RUNLOCK(ifp); if (lle == NULL) { - IF_AFDATA_CFG_WLOCK(ifp); lle = nd6_create(&sin6->sin6_addr, 0, ifp); - IF_AFDATA_CFG_WUNLOCK(ifp); if (lle == NULL) return (ENOMEM); /* Couldn't create entry in cache. */ lle->ln_state = ND6_LLINFO_INCOMPLETE; - nd6_llinfo_settimer_locked(lle, - (long)ND_IFINFO(ifp)->retrans * hz / 1000); - LLE_WUNLOCK(lle); + IF_AFDATA_CFG_WLOCK(ifp); + LLE_WLOCK(lle); + /* Check if the same record was addded */ + lle_tmp = lltable_lookup_lle(LLTABLE6(ifp), LLE_EXCLUSIVE, sa); + if (lle_tmp == NULL) { + /* + * No entry has been found. Link new one. + */ + IF_AFDATA_RUN_WLOCK(ifp); + llentry_link(LLTABLE6(ifp), lle); + IF_AFDATA_RUN_WUNLOCK(ifp); + } + IF_AFDATA_CFG_WUNLOCK(ifp); + if (lle_tmp == NULL) { + /* Set up timer for our new lle */ + nd6_llinfo_settimer_locked(lle, + (long)ND_IFINFO(ifp)->retrans * hz / 1000); + LLE_WUNLOCK(lle); - nd6_ns_output(ifp, NULL, &sin6->sin6_addr, NULL, 0); + nd6_ns_output(ifp, NULL, &sin6->sin6_addr, NULL, 0); + + return (EWOULDBLOCK); + } - return (EWOULDBLOCK); + /* Existing lle has been found. Free new one */ + LLE_FREE_LOCKED(lle); + lle = lle_tmp; + lle_tmp = NULL; + flags |= LLE_EXCLUSIVE; } if (lle->ln_state == ND6_LLINFO_STALE) { Modified: projects/routing/sys/netinet6/in6.c ============================================================================== --- projects/routing/sys/netinet6/in6.c Sun Dec 7 11:21:41 2014 (r275576) +++ projects/routing/sys/netinet6/in6.c Sun Dec 7 15:42:46 2014 (r275577) @@ -2052,14 +2052,12 @@ struct in6_llentry { }; /* - * Deletes an address from the address table. - * This function is called by the timer functions - * such as arptimer() and nd6_llinfo_timer(), and - * the caller does the locking. + * Frees already unlinked @lle. */ static void -in6_lltable_free(struct lltable *llt, struct llentry *lle) +in6_lltable_free(struct llentry *lle) { + LLE_WUNLOCK(lle); LLE_LOCK_DESTROY(lle); free(lle, M_LLTABLE); @@ -2087,17 +2085,6 @@ in6_lltable_new(const struct sockaddr *l return (&lle->base); } -static void -in6_lltable_stop_timers(struct llentry *lle) -{ - - LLE_WLOCK_ASSERT(lle); - if (callout_stop(&lle->la_timer)) { - LLE_REMREF(lle); - lle->la_flags &= ~LLE_CALLOUTREF; - } -} - static int in6_lltable_match_prefix(const struct sockaddr *prefix, const struct sockaddr *mask, u_int flags, struct llentry *lle) @@ -2219,19 +2206,13 @@ static struct llentry * in6_lltable_create(struct lltable *llt, u_int flags, const struct sockaddr *l3addr) { - const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)l3addr; struct ifnet *ifp = llt->llt_ifp; struct llentry *lle; KASSERT(l3addr->sa_family == AF_INET6, ("sin_family %d", l3addr->sa_family)); - lle = in6_lltable_find_dst(llt, &sin6->sin6_addr); - - if (lle != NULL) { - LLE_WLOCK(lle); - return (lle); - } + IF_AFDATA_CFG_UNLOCK_ASSERT(ifp); /* * A route that covers the given address must have @@ -2248,7 +2229,6 @@ in6_lltable_create(struct lltable *llt, return NULL; } lle->la_flags = flags; - LLE_WLOCK(lle); return (lle); } @@ -2381,7 +2361,7 @@ in6_domifattach(struct ifnet *ifp) ext->lltable->llt_delete = in6_lltable_delete; ext->lltable->llt_dump_entry = in6_lltable_dump_entry; ext->lltable->llt_hash = in6_lltable_hash; - ext->lltable->llt_stop_timers = in6_lltable_stop_timers; + ext->lltable->llt_clear_entry = nd6_lltable_clear_entry; ext->lltable->llt_match_prefix = in6_lltable_match_prefix; } Modified: projects/routing/sys/netinet6/nd6.c ============================================================================== --- projects/routing/sys/netinet6/nd6.c Sun Dec 7 11:21:41 2014 (r275576) +++ projects/routing/sys/netinet6/nd6.c Sun Dec 7 15:42:46 2014 (r275577) @@ -132,10 +132,14 @@ static int nd6_is_new_addr_neighbor(stru static void nd6_setmtu0(struct ifnet *, struct nd_ifinfo *); static void nd6_slowtimo(void *); static int regen_tmpaddr(struct in6_ifaddr *); -static struct llentry *nd6_free(struct llentry *, int); +static void nd6_free(struct llentry *, int); static void nd6_llinfo_timer(void *); static void clear_llinfo_pqueue(struct llentry *); static void nd6_rtrequest(int, struct rtentry *, struct rt_addrinfo *); +static struct in6_addr *nd6_llinfo_get_holdsrc(struct llentry *, + struct in6_addr *); +static int nd6_check_del_defrtr(struct lltable *, struct llentry *); +static void nd6_check_recalc_defrtr(struct lltable *, struct llentry *); static VNET_DEFINE(struct callout, nd6_slowtimo_ch); #define V_nd6_slowtimo_ch VNET(nd6_slowtimo_ch) @@ -433,6 +437,10 @@ nd6_llinfo_settimer_locked(struct llentr ln->la_expire = 0; ln->ln_ntick = 0; canceled = callout_stop(&ln->ln_timer_ch); + if (canceled != 0) { + ln->la_flags &= ~LLE_CALLOUTREF; + LLE_REMREF(ln); + } } else { ln->la_expire = time_uptime + tick / hz; LLE_ADDREF(ln); @@ -445,11 +453,11 @@ nd6_llinfo_settimer_locked(struct llentr canceled = callout_reset(&ln->ln_timer_ch, tick, nd6_llinfo_timer, ln); } + if (canceled != 0) + LLE_REMREF(ln); + else + ln->la_flags |= LLE_CALLOUTREF; } - if (canceled) - LLE_REMREF(ln); - else - ln->la_flags |= LLE_CALLOUTREF; } void @@ -461,6 +469,34 @@ nd6_llinfo_settimer(struct llentry *ln, LLE_WUNLOCK(ln); } +/* + * Gets source address of the first packet in hold queue + * and stores it in @src. + * Returns pointer to @src (if hold queue is not empty) or NULL. + * + */ +static struct in6_addr * +nd6_llinfo_get_holdsrc(struct llentry *ln, struct in6_addr *src) +{ + struct ip6_hdr *phdr; + + if (ln->la_hold == NULL) + return (NULL); + + /* + * assuming every packet in la_hold has the same IP + * header + */ + phdr = mtod(ln->la_hold, struct ip6_hdr *); + /* XXX pullup? */ + if (sizeof(*phdr) < ln->la_hold->m_len) { + *src = phdr->ip6_src; + return (src); + } + + return (NULL); +} + static void nd6_llinfo_timer(void *arg) { @@ -468,13 +504,28 @@ nd6_llinfo_timer(void *arg) struct in6_addr *dst; struct ifnet *ifp; struct nd_ifinfo *ndi = NULL; + struct in6_addr src, *psrc; KASSERT(arg != NULL, ("%s: arg NULL", __func__)); ln = (struct llentry *)arg; LLE_WLOCK_ASSERT(ln); - ifp = ln->lle_tbl->llt_ifp; - CURVNET_SET(ifp->if_vnet); + if (ln->la_flags & LLE_STATIC) { + /* TODO: ensure we won't get here */ + LLE_WUNLOCK(ln); + return; + } + + if (ln->la_flags & LLE_DELETED) { + /* We have been deleted. Drop callref and return */ + KASSERT((ln->la_flags & LLE_CALLOUTREF) != 0, + ("nd6_llinfo_timer was called without callout reference")); + + /* Assume the entry was already cleared */ + ln->la_flags &= ~LLE_CALLOUTREF; + LLE_FREE_LOCKED(ln); + return; + } if (ln->ln_ntick > 0) { if (ln->ln_ntick > INT_MAX) { @@ -484,29 +535,27 @@ nd6_llinfo_timer(void *arg) ln->ln_ntick = 0; nd6_llinfo_settimer_locked(ln, ln->ln_ntick); } - goto done; + LLE_WUNLOCK(ln); + return; } + ifp = ln->lle_tbl->llt_ifp; + CURVNET_SET(ifp->if_vnet); + ndi = ND_IFINFO(ifp); dst = &L3_ADDR_SIN6(ln)->sin6_addr; - if (ln->la_flags & LLE_STATIC) { - goto done; - } - - if (ln->la_flags & LLE_DELETED) { - (void)nd6_free(ln, 0); - ln = NULL; - goto done; - } + /* + * Each case statement needs to unlock @ln before break/return. + */ switch (ln->ln_state) { case ND6_LLINFO_INCOMPLETE: if (ln->la_asked < V_nd6_mmaxtries) { ln->la_asked++; nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000); + psrc = nd6_llinfo_get_holdsrc(ln, &src); LLE_WUNLOCK(ln); - nd6_ns_output(ifp, NULL, dst, ln, 0); - LLE_WLOCK(ln); + nd6_ns_output(ifp, NULL, dst, psrc, 0); } else { struct mbuf *m = ln->la_hold; if (m) { @@ -522,7 +571,7 @@ nd6_llinfo_timer(void *arg) clear_llinfo_pqueue(ln); } EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_TIMEDOUT); - (void)nd6_free(ln, 0); + nd6_free(ln, 0); ln = NULL; if (m != NULL) icmp6_error2(m, ICMP6_DST_UNREACH, @@ -534,15 +583,17 @@ nd6_llinfo_timer(void *arg) ln->ln_state = ND6_LLINFO_STALE; nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); } + LLE_WUNLOCK(ln); break; case ND6_LLINFO_STALE: /* Garbage Collection(RFC 2461 5.3) */ if (!ND6_LLINFO_PERMANENT(ln)) { EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED); - (void)nd6_free(ln, 1); + nd6_free(ln, 1); ln = NULL; } + LLE_WUNLOCK(ln); break; case ND6_LLINFO_DELAY: @@ -551,24 +602,25 @@ nd6_llinfo_timer(void *arg) ln->la_asked = 1; ln->ln_state = ND6_LLINFO_PROBE; nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000); + psrc = nd6_llinfo_get_holdsrc(ln, &src); LLE_WUNLOCK(ln); - nd6_ns_output(ifp, dst, dst, ln, 0); - LLE_WLOCK(ln); + nd6_ns_output(ifp, dst, dst, psrc, 0); } else { ln->ln_state = ND6_LLINFO_STALE; /* XXX */ nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); + LLE_WUNLOCK(ln); } break; case ND6_LLINFO_PROBE: if (ln->la_asked < V_nd6_umaxtries) { ln->la_asked++; nd6_llinfo_settimer_locked(ln, (long)ndi->retrans * hz / 1000); + psrc = nd6_llinfo_get_holdsrc(ln, &src); LLE_WUNLOCK(ln); - nd6_ns_output(ifp, dst, dst, ln, 0); - LLE_WLOCK(ln); + nd6_ns_output(ifp, dst, dst, psrc, 0); } else { EVENTHANDLER_INVOKE(lle_event, ln, LLENTRY_EXPIRED); - (void)nd6_free(ln, 0); + nd6_free(ln, 0); ln = NULL; } break; @@ -576,9 +628,7 @@ nd6_llinfo_timer(void *arg) panic("%s: paths in a dark night can be confusing: %d", __func__, ln->ln_state); } -done: - if (ln != NULL) - LLE_FREE_LOCKED(ln); + CURVNET_RESTORE(); } @@ -866,9 +916,8 @@ nd6_lookup(struct in6_addr *addr6, int f return (ln); } -/* - * the caller acquires and releases the lock on the lltbls - * Returns the llentry wlocked +/* + * Creates and returns new, unlinked and unlocked lle. */ struct llentry * nd6_create(struct in6_addr *addr6, int flags, struct ifnet *ifp) @@ -881,15 +930,10 @@ nd6_create(struct in6_addr *addr6, int f sin6.sin6_family = AF_INET6; sin6.sin6_addr = *addr6; - IF_AFDATA_CFG_WLOCK_ASSERT(ifp); + IF_AFDATA_CFG_UNLOCK_ASSERT(ifp); ln = lltable_create_lle(LLTABLE6(ifp), 0, (struct sockaddr *)&sin6); - if (ln != NULL) { - IF_AFDATA_RUN_WLOCK(ifp); - ln->ln_state = ND6_LLINFO_NOSTATE; - llentry_link(LLTABLE6(ifp), ln); - IF_AFDATA_RUN_WUNLOCK(ifp); - } + ln->ln_state = ND6_LLINFO_NOSTATE; return (ln); } @@ -1025,34 +1069,96 @@ nd6_is_addr_neighbor(struct sockaddr_in6 /* * Free an nd6 llinfo entry. - * Since the function would cause significant changes in the kernel, DO NOT - * make it global, unless you have a strong reason for the change, and are sure - * that the change is safe. + * Internal function used by timer code. */ -static struct llentry * +static void nd6_free(struct llentry *ln, int gc) { - struct llentry *next; - struct nd_defrouter *dr; + struct lltable *llt; + + LLE_WLOCK_ASSERT(ln); + + if ((ln->la_flags & LLE_DELETED) != 0) { + /* Unlinked entry. Stop timer/callout. */ + nd6_llinfo_settimer_locked(ln, -1); + llentry_free(ln); + return; + } + + llt = ln->lle_tbl; + /* Check if we can delete/unlink given entry */ + if (gc != 0 && nd6_check_del_defrtr(llt, ln) == 0) { + LLE_WUNLOCK(ln); + return; + } + + llt->llt_clear_entry(ln->lle_tbl, ln); +} + +/* + * Calback for lltable. + */ +void +nd6_lltable_clear_entry(struct lltable *llt, struct llentry *ln) +{ struct ifnet *ifp; LLE_WLOCK_ASSERT(ln); + KASSERT(llt != NULL, ("lltable is NULL")); - /* - * we used to have pfctlinput(PRC_HOSTDEAD) here. - * even though it is not harmful, it was not really necessary. - */ + /* Unlink entry from table */ + if ((ln->la_flags & LLE_LINKED) != 0) { + + ifp = llt->llt_ifp; + /* + * Lock order needs to be maintained + */ + LLE_ADDREF(ln); + LLE_WUNLOCK(ln); + IF_AFDATA_CFG_WLOCK(ifp); + LLE_WLOCK(ln); + LLE_REMREF(ln); + + IF_AFDATA_RUN_WLOCK(ifp); + llentry_unlink(ln); + IF_AFDATA_RUN_WUNLOCK(ifp); + + IF_AFDATA_CFG_WUNLOCK(ifp); + } /* cancel timer */ nd6_llinfo_settimer_locked(ln, -1); - ifp = ln->lle_tbl->llt_ifp; + /* Check if default router needs to be recalculated */ + nd6_check_recalc_defrtr(llt, ln); + + /* Finally, free entry */ + llentry_free(ln); +} + +/* + * Checks if we can delete given entry. + * Perfoms defrtr selection if needed. + * + * return non-zero value if lle can be deleted. + */ +static int +nd6_check_del_defrtr(struct lltable *llt, struct llentry *ln) +{ + struct ifnet *ifp; + struct nd_defrouter *dr; + struct in6_addr dst; + + ifp = llt->llt_ifp; + dst = L3_ADDR_SIN6(ln)->sin6_addr; + + LLE_WLOCK_ASSERT(ln); if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { - dr = defrouter_lookup(&L3_ADDR_SIN6(ln)->sin6_addr, ifp); + dr = defrouter_lookup(&dst, ifp); if (dr != NULL && dr->expire && - ln->ln_state == ND6_LLINFO_STALE && gc) { + ln->ln_state == ND6_LLINFO_STALE) { /* * If the reason for the deletion is just garbage * collection, and the neighbor is an active default @@ -1072,11 +1178,27 @@ nd6_free(struct llentry *ln, int gc) nd6_llinfo_settimer_locked(ln, (long)V_nd6_gctimer * hz); - next = LIST_NEXT(ln, lle_next); - LLE_REMREF(ln); - LLE_WUNLOCK(ln); - return (next); + return (0); } + } + + return (1); +} + +static void +nd6_check_recalc_defrtr(struct lltable *llt, struct llentry *ln) +{ + struct ifnet *ifp; + struct nd_defrouter *dr; + struct in6_addr dst; + + ifp = llt->llt_ifp; + dst = L3_ADDR_SIN6(ln)->sin6_addr; + + LLE_WLOCK_ASSERT(ln); + + if (ND_IFINFO(ifp)->flags & ND6_IFF_ACCEPT_RTADV) { + dr = defrouter_lookup(&dst, ifp); if (dr) { /* @@ -1103,6 +1225,7 @@ nd6_free(struct llentry *ln, int gc) * defrouter_select() in the block further down for calls * into nd6_lookup(). We still hold a ref. */ + LLE_ADDREF(ln); LLE_WUNLOCK(ln); /* @@ -1110,7 +1233,7 @@ nd6_free(struct llentry *ln, int gc) * is in the Default Router List. * See a corresponding comment in nd6_na_input(). */ - rt6_flush(&L3_ADDR_SIN6(ln)->sin6_addr, ifp); + rt6_flush(&dst, ifp); } if (dr) { @@ -1128,44 +1251,11 @@ nd6_free(struct llentry *ln, int gc) defrouter_select(); } - if (ln->ln_router || dr) + if (ln->ln_router || dr) { LLE_WLOCK(ln); + LLE_REMREF(ln); + } } - - /* - * Before deleting the entry, remember the next entry as the - * return value. We need this because pfxlist_onlink_check() above - * might have freed other entries (particularly the old next entry) as - * a side effect (XXX). - */ - next = LIST_NEXT(ln, lle_next); - - /* - * Save to unlock. We still hold an extra reference and will not - * free(9) in llentry_free() if someone else holds one as well. - */ - LLE_WUNLOCK(ln); - IF_AFDATA_CFG_WLOCK(ifp); - LLE_WLOCK(ln); - - /* - * Note other thread could have removed given entry - * stopping callout and removing LLE reference. - */ - if ((ln->la_flags & LLE_CALLOUTREF) != 0) { - LLE_REMREF(ln); - ln->la_flags &= ~LLE_CALLOUTREF; - } - - IF_AFDATA_RUN_WLOCK(ifp); - llentry_unlink(ln); - IF_AFDATA_RUN_WUNLOCK(ifp); - - llentry_free(ln); - - IF_AFDATA_CFG_WUNLOCK(ifp); - - return (next); } /* @@ -1564,6 +1654,79 @@ nd6_ioctl(u_long cmd, caddr_t data, stru return (error); } +static int +nd6_check_router(int type, int code, int is_new, int old_addr, int new_addr, + int ln_router) +{ + + /* + * ICMP6 type dependent behavior. + * + * NS: clear IsRouter if new entry + * RS: clear IsRouter + * RA: set IsRouter if there's lladdr + * redir: clear IsRouter if new entry + * + * RA case, (1): + * The spec says that we must set IsRouter in the following cases: + * - If lladdr exist, set IsRouter. This means (1-5). + * - If it is old entry (!newentry), set IsRouter. This means (7). + * So, based on the spec, in (1-5) and (7) cases we must set IsRouter. + * A quetion arises for (1) case. (1) case has no lladdr in the + * neighbor cache, this is similar to (6). + * This case is rare but we figured that we MUST NOT set IsRouter. + * + * newentry olladdr lladdr llchange NS RS RA redir + * D R + * 0 n n -- (1) c ? s + * 0 y n -- (2) c s s + * 0 n y -- (3) c s s + * 0 y y n (4) c s s + * 0 y y y (5) c s s + * 1 -- n -- (6) c c c s + * 1 -- y -- (7) c c s c s + * + * (c=clear s=set) + */ + switch (type & 0xff) { + case ND_NEIGHBOR_SOLICIT: + /* + * New entry must have is_router flag cleared. + */ + if (is_new) /* (6-7) */ + ln_router = 0; + break; + case ND_REDIRECT: + /* + * If the icmp is a redirect to a better router, always set the + * is_router flag. Otherwise, if the entry is newly created, + * clear the flag. [RFC 2461, sec 8.3] + */ + if (code == ND_REDIRECT_ROUTER) + ln_router = 1; + else if (is_new) /* (6-7) */ + ln_router = 0; + break; + case ND_ROUTER_SOLICIT: + /* + * is_router flag must always be cleared. + */ + ln_router = 0; + break; + case ND_ROUTER_ADVERT: + /* + * Mark an entry with lladdr as a router. + */ + if ((!is_new && (old_addr || new_addr)) || /* (2-5) */ + (is_new && new_addr)) { /* (7) */ + ln_router = 1; + } + break; + } + + return (ln_router); +} *** DIFF OUTPUT TRUNCATED AT 1000 LINES ***
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