Partially merge r274887,r275334,r275577,r275578,r275586 to minimize

differences between projects/routing and HEAD.

This commit tries to keep code logic the same while changing underlying
code to use unified callbacks.

* Add llt_foreach_entry method to traverse all entries in given llt
* Add llt_dump_entry method to export particular lle entry in sysctl/rtsock
  format (code is not indented properly to minimize diff). Will be fixed
  in the next commits.
* Add llt_link_entry/llt_unlink_entry methods to link/unlink particular lle.
* Add llt_fill_sa_entry method to export address in the lle to sockaddr
  format.
* Add llt_hash method to use in generic hash table support code.
* Add llt_free_entry method which is used in llt_prefix_free code.

* Prepare for fine-grained locking by separating lle unlink and deletion in
  lltable_free() and lltable_prefix_free().

* Provide lltable_get<ifp|af>() functions to reduce direct 'struct lltable'
 access by external callers.

* Remove @llt agrument from lle_free() lle callback since it was unused.
* Temporarily add L3_CADDR() macro for 'const' sockaddr typecasting.
* Switch to per-af hashing code.
* Rename LLE_FREE_LOCKED() callback from in[6]_lltable_free() to
  in_[6]lltable_destroy() to avoid clashing with llt_free_entry() method.
  Update description from these functions.
* Use unified lltable_free_entry() function instead of per-af one.

Reviewed by:	ae

1 files changed, 96 insertions, 80 deletions

diff --git a/sys/netinet/in.c b/sys/netinet/in.c
index 9d3642e..5f3620a 100644
--- a/sys/netinet/in.c
+++ b/sys/netinet/in.c
@@ -961,15 +961,19 @@ struct in_llentry {
 	struct sockaddr_in	l3_addr4;
 };
 
+#define	IN_LLTBL_DEFAULT_HSIZE	32
+#define	IN_LLTBL_HASH(k, h) \
+	(((((((k >> 8) ^ k) >> 8) ^ k) >> 8) ^ k) & ((h) - 1))
+
 /*
- * 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.
+ * Do actual deallocation of @lle.
+ * Called by LLE_FREE_LOCKED when number of references
+ * drops to zero.
  */
 static void
-in_lltable_free(struct lltable *llt, struct llentry *lle)
+in_lltable_destroy_lle(struct llentry *lle)
 {
+
 	LLE_WUNLOCK(lle);
 	LLE_LOCK_DESTROY(lle);
 	free(lle, M_LLTABLE);
@@ -991,7 +995,7 @@ in_lltable_new(const struct sockaddr *l3addr, u_int flags)
 	lle->base.la_expire = time_uptime; /* mark expired */
 	lle->l3_addr4 = *(const struct sockaddr_in *)l3addr;
 	lle->base.lle_refcnt = 1;
-	lle->base.lle_free = in_lltable_free;
+	lle->base.lle_free = in_lltable_destroy_lle;
 	LLE_LOCK_INIT(&lle->base);
 	callout_init(&lle->base.la_timer, 1);
 
@@ -1001,37 +1005,48 @@ in_lltable_new(const struct sockaddr *l3addr, u_int flags)
 #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 )
 
-static void
-in_lltable_prefix_free(struct lltable *llt, const struct sockaddr *prefix,
-    const struct sockaddr *mask, u_int flags)
+static int
+in_lltable_match_prefix(const struct sockaddr *prefix,
+    const struct sockaddr *mask, u_int flags, struct llentry *lle)
 {
 	const struct sockaddr_in *pfx = (const struct sockaddr_in *)prefix;
 	const struct sockaddr_in *msk = (const struct sockaddr_in *)mask;
-	struct llentry *lle, *next;
-	int i;
+
+	/*
+	 * (flags & LLE_STATIC) means deleting all entries
+	 * including static ARP entries.
+	 */
+	if (IN_ARE_MASKED_ADDR_EQUAL(satosin(L3_ADDR(lle)), pfx, msk) &&
+	    ((flags & LLE_STATIC) || !(lle->la_flags & LLE_STATIC)))
+		return (1);
+
+	return (0);
+}
+
+static void
+in_lltable_free_entry(struct lltable *llt, struct llentry *lle)
+{
+	struct ifnet *ifp;
 	size_t pkts_dropped;
 
-	IF_AFDATA_WLOCK(llt->llt_ifp);
-	for (i = 0; i < LLTBL_HASHTBL_SIZE; i++) {
-		LIST_FOREACH_SAFE(lle, &llt->lle_head[i], lle_next, next) {
-			/*
-			 * (flags & LLE_STATIC) means deleting all entries
-			 * including static ARP entries.
-			 */
-			if (IN_ARE_MASKED_ADDR_EQUAL(satosin(L3_ADDR(lle)),
-			    pfx, msk) && ((flags & LLE_STATIC) ||
-			    !(lle->la_flags & LLE_STATIC))) {
-				LLE_WLOCK(lle);
-				if (callout_stop(&lle->la_timer))
-					LLE_REMREF(lle);
-				pkts_dropped = llentry_free(lle);
-				ARPSTAT_ADD(dropped, 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;
+		IF_AFDATA_WLOCK_ASSERT(ifp);
+		lltable_unlink_entry(llt, lle);
 	}
-	IF_AFDATA_WUNLOCK(llt->llt_ifp);
-}
 
+	/* cancel timer */
+	if (callout_stop(&lle->la_timer))
+		LLE_REMREF(lle);
+
+	/* Drop hold queue */
+	pkts_dropped = llentry_free(lle);
+	ARPSTAT_ADD(dropped, pkts_dropped);
+}
 
 static int
 in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr)
@@ -1107,16 +1122,45 @@ in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr
 	return (0);
 }
 
+static inline uint32_t
+in_lltable_hash_dst(const struct in_addr dst, uint32_t hsize)
+{
+
+	return (IN_LLTBL_HASH(dst.s_addr, hsize));
+}
+
+static uint32_t
+in_lltable_hash(const struct llentry *lle, uint32_t hsize)
+{
+	const struct sockaddr_in *sin;
+
+	sin = (const struct sockaddr_in *)(L3_CADDR(lle));
+
+	return (in_lltable_hash_dst(sin->sin_addr, hsize));
+}
+
+static void
+in_lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa)
+{
+	struct sockaddr_in *sin;
+
+	sin = (struct sockaddr_in *)sa;
+	bzero(sin, sizeof(*sin));
+	sin->sin_family = AF_INET;
+	sin->sin_len = sizeof(*sin);
+	sin->sin_addr = ((const struct sockaddr_in *)(L3_CADDR(lle)))->sin_addr;
+}
+
 static inline struct llentry *
 in_lltable_find_dst(struct lltable *llt, struct in_addr dst)
 {
 	struct llentry *lle;
 	struct llentries *lleh;
 	struct sockaddr_in *sin;
-	u_int hashkey;
+	u_int hashidx;
 
-	hashkey = dst.s_addr;
-	lleh = &llt->lle_head[LLATBL_HASH(hashkey, LLTBL_HASHMASK)];
+	hashidx = in_lltable_hash_dst(dst, LLTBL_HASHTBL_SIZE);
+	lleh = &llt->lle_head[hashidx];
 	LIST_FOREACH(lle, lleh, lle_next) {
 		sin = satosin(L3_ADDR(lle));
 		if (lle->la_flags & LLE_DELETED)
@@ -1169,8 +1213,6 @@ in_lltable_create(struct lltable *llt, u_int flags, const struct sockaddr *l3add
 	const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr;
 	struct ifnet *ifp = llt->llt_ifp;
 	struct llentry *lle;
-	struct llentries *lleh;
-	u_int hashkey;
 
 	IF_AFDATA_WLOCK_ASSERT(ifp);
 	KASSERT(l3addr->sa_family == AF_INET,
@@ -1205,13 +1247,7 @@ in_lltable_create(struct lltable *llt, u_int flags, const struct sockaddr *l3add
 		lle->la_flags |= (LLE_VALID | LLE_STATIC);
 	}
 
-	hashkey = sin->sin_addr.s_addr;
-	lleh = &llt->lle_head[LLATBL_HASH(hashkey, LLTBL_HASHMASK)];
-
-	lle->lle_tbl  = llt;
-	lle->lle_head = lleh;
-	lle->la_flags |= LLE_LINKED;
-	LIST_INSERT_HEAD(lleh, lle, lle_next);
+	lltable_link_entry(llt, lle);
 	LLE_WLOCK(lle);
 
 	return (lle);
@@ -1226,22 +1262,11 @@ in_lltable_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3add
 {
 	const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr;
 	struct llentry *lle;
-	struct llentries *lleh;
-	u_int hashkey;
 
 	IF_AFDATA_LOCK_ASSERT(llt->llt_ifp);
 	KASSERT(l3addr->sa_family == AF_INET,
 	    ("sin_family %d", l3addr->sa_family));
-
-	hashkey = sin->sin_addr.s_addr;
-	lleh = &llt->lle_head[LLATBL_HASH(hashkey, LLTBL_HASHMASK)];
-	LIST_FOREACH(lle, lleh, lle_next) {
-		struct sockaddr_in *sa2 = satosin(L3_ADDR(lle));
-		if (lle->la_flags & LLE_DELETED)
-			continue;
-		if (sa2->sin_addr.s_addr == sin->sin_addr.s_addr)
-			break;
-	}
+	lle = in_lltable_find_dst(llt, sin->sin_addr);
 
 	if (lle == NULL)
 		return (NULL);
@@ -1255,47 +1280,39 @@ in_lltable_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3add
 }
 
 static int
-in_lltable_dump(struct lltable *llt, struct sysctl_req *wr)
+in_lltable_dump_entry(struct lltable *llt, struct llentry *lle,
+    struct sysctl_req *wr)
 {
-#define	SIN(lle)	((struct sockaddr_in *) L3_ADDR(lle))
 	struct ifnet *ifp = llt->llt_ifp;
-	struct llentry *lle;
 	/* XXX stack use */
 	struct {
 		struct rt_msghdr	rtm;
 		struct sockaddr_in	sin;
 		struct sockaddr_dl	sdl;
 	} arpc;
-	int error, i;
-
-	LLTABLE_LOCK_ASSERT();
-
-	error = 0;
-	for (i = 0; i < LLTBL_HASHTBL_SIZE; i++) {
-		LIST_FOREACH(lle, &llt->lle_head[i], lle_next) {
-			struct sockaddr_dl *sdl;
+	struct sockaddr_dl *sdl;
+	int error;
 
+	bzero(&arpc, sizeof(arpc));
 			/* skip deleted entries */
 			if ((lle->la_flags & LLE_DELETED) == LLE_DELETED)
-				continue;
+				return (0);
 			/* Skip if jailed and not a valid IP of the prison. */
-			if (prison_if(wr->td->td_ucred, L3_ADDR(lle)) != 0)
-				continue;
+			lltable_fill_sa_entry(lle,(struct sockaddr *)&arpc.sin);
+			if (prison_if(wr->td->td_ucred,
+			    (struct sockaddr *)&arpc.sin) != 0)
+				return (0);
 			/*
 			 * produce a msg made of:
 			 *  struct rt_msghdr;
 			 *  struct sockaddr_in; (IPv4)
 			 *  struct sockaddr_dl;
 			 */
-			bzero(&arpc, sizeof(arpc));
 			arpc.rtm.rtm_msglen = sizeof(arpc);
 			arpc.rtm.rtm_version = RTM_VERSION;
 			arpc.rtm.rtm_type = RTM_GET;
 			arpc.rtm.rtm_flags = RTF_UP;
 			arpc.rtm.rtm_addrs = RTA_DST | RTA_GATEWAY;
-			arpc.sin.sin_family = AF_INET;
-			arpc.sin.sin_len = sizeof(arpc.sin);
-			arpc.sin.sin_addr.s_addr = SIN(lle)->sin_addr.s_addr;
 
 			/* publish */
 			if (lle->la_flags & LLE_PUB)
@@ -1321,12 +1338,8 @@ in_lltable_dump(struct lltable *llt, struct sysctl_req *wr)
 				arpc.rtm.rtm_flags |= RTF_STATIC;
 			arpc.rtm.rtm_index = ifp->if_index;
 			error = SYSCTL_OUT(wr, &arpc, sizeof(arpc));
-			if (error)
-				break;
-		}
-	}
-	return error;
-#undef SIN
+
+	return (error);
 }
 
 void *
@@ -1339,11 +1352,14 @@ in_domifattach(struct ifnet *ifp)
 
 	llt = lltable_init(ifp, AF_INET);
 	if (llt != NULL) {
-		llt->llt_prefix_free = in_lltable_prefix_free;
 		llt->llt_lookup = in_lltable_lookup;
 		llt->llt_create = in_lltable_create;
 		llt->llt_delete = in_lltable_delete;
-		llt->llt_dump = in_lltable_dump;
+		llt->llt_dump_entry = in_lltable_dump_entry;
+		llt->llt_hash = in_lltable_hash;
+		llt->llt_fill_sa_entry = in_lltable_fill_sa_entry;
+		llt->llt_free_entry = in_lltable_free_entry;
+		llt->llt_match_prefix = in_lltable_match_prefix;
 	}
 	ii->ii_llt = llt;