git: 29029b06a6f7 - main - routing: remove info argument from add/change_route_nhop().

From: Alexander V. Chernikov <melifaro_at_FreeBSD.org>
Date: Mon, 01 Aug 2022 08:53:22 UTC
The branch main has been updated by melifaro:

URL: https://cgit.FreeBSD.org/src/commit/?id=29029b06a6f7fd51c34c9db88cc98a6653ee5046

commit 29029b06a6f7fd51c34c9db88cc98a6653ee5046
Author:     Alexander V. Chernikov <melifaro@FreeBSD.org>
AuthorDate: 2022-07-28 13:41:11 +0000
Commit:     Alexander V. Chernikov <melifaro@FreeBSD.org>
CommitDate: 2022-08-01 07:41:07 +0000

    routing: remove info argument from add/change_route_nhop().
    
    Currently, rt_addrinfo(info) serves as a main "transport" moving
     state between various functions inside the routing subsystem.
    As all of the fields are filled in directly by the customers, it
     is problematic to maintain consistency, resulting in repeated checks
     inside many functions. Additionally, there are multiple ways of
     specifying the same value (RTAX_IFP vs rti_ifp / rti_ifa) and so on.
    With the upcoming nhop(9) kpi it is possible to store all of the
     required state in the nexthops in the consistent fashion, reducing the
     need to use "info" in the KPI calls.
    Finally, rt_addrinfo structure format was derived from the rtsock wire
     format, which is different from other kernel routing users or netlink.
    
    This cleanup simplifies upcoming nhop(9) kpi and netlink introduction.
    
    Reviewed by:    zlei.huang@gmail.com
    Differential Revision: https://reviews.freebsd.org/D35972
    MFC after:      2 weeks
---
 sys/net/route/mpath_ctl.c |  2 +-
 sys/net/route/route_ctl.c | 35 ++++++++++++++---------------------
 sys/net/route/route_var.h |  3 +--
 3 files changed, 16 insertions(+), 24 deletions(-)

diff --git a/sys/net/route/mpath_ctl.c b/sys/net/route/mpath_ctl.c
index 8351437e34c6..db3c757e818d 100644
--- a/sys/net/route/mpath_ctl.c
+++ b/sys/net/route/mpath_ctl.c
@@ -188,7 +188,7 @@ del_route_mpath(struct rib_head *rh, struct rt_addrinfo *info,
 			nhop_free_any(rnd.rnd_nhop);
 			return (ESRCH);
 		}
-		error = change_route_nhop(rh, rt, info, &rnd, rc);
+		error = change_route_nhop(rh, rt, &rnd, rc);
 	}
 	return (error);
 }
diff --git a/sys/net/route/route_ctl.c b/sys/net/route/route_ctl.c
index 1127c504400e..80682b7f3b87 100644
--- a/sys/net/route/route_ctl.c
+++ b/sys/net/route/route_ctl.c
@@ -80,8 +80,7 @@ struct rib_subscription {
 static int add_route(struct rib_head *rnh, struct rt_addrinfo *info,
     struct rib_cmd_info *rc);
 static int add_route_nhop(struct rib_head *rnh, struct rtentry *rt,
-    struct rt_addrinfo *info, struct route_nhop_data *rnd,
-    struct rib_cmd_info *rc);
+    struct route_nhop_data *rnd, struct rib_cmd_info *rc);
 static int del_route(struct rib_head *rnh, struct rt_addrinfo *info,
     struct rib_cmd_info *rc);
 static int change_route(struct rib_head *rnh, struct rt_addrinfo *info,
@@ -618,6 +617,8 @@ check_gateway(struct rib_head *rnh, struct sockaddr *dst,
 /*
  * Creates rtentry and nexthop based on @info data.
  * Return 0 and fills in rtentry into @prt on success,
+ * Note: rtentry mask will be set to RTAX_NETMASK, thus its pointer is required
+ *  to be stable till the end of the operation (radix rt insertion/change/removal).
  * return errno otherwise.
  */
 static int
@@ -685,6 +686,8 @@ create_rtentry(struct rib_head *rnh, struct rt_addrinfo *info,
 		rt_maskedcopy(dst, ndst, netmask);
 	} else
 		bcopy(dst, ndst, dst->sa_len);
+	/* Set netmask to the storage from info. It will be updated upon insertion */
+	rt_mask(rt) = netmask;
 
 	/*
 	 * We use the ifa reference returned by rt_getifa_fib().
@@ -716,7 +719,7 @@ add_route(struct rib_head *rnh, struct rt_addrinfo *info,
 	nh = rt->rt_nhop;
 
 	RIB_WLOCK(rnh);
-	error = add_route_nhop(rnh, rt, info, &rnd_add, rc);
+	error = add_route_nhop(rnh, rt, &rnd_add, rc);
 	if (error == 0) {
 		RIB_WUNLOCK(rnh);
 		return (0);
@@ -737,7 +740,7 @@ add_route(struct rib_head *rnh, struct rt_addrinfo *info,
 	/* Check if new route has higher preference */
 	if (can_override_nhop(info, nh_orig) > 0) {
 		/* Update nexthop to the new route */
-		change_route_nhop(rnh, rt_orig, info, &rnd_add, rc);
+		change_route_nhop(rnh, rt_orig, &rnd_add, rc);
 		RIB_WUNLOCK(rnh);
 		uma_zfree(V_rtzone, rt);
 		nhop_free(nh_orig);
@@ -851,8 +854,7 @@ rt_unlinkrte(struct rib_head *rnh, struct rt_addrinfo *info, struct rib_cmd_info
 	 * Remove the item from the tree and return it.
 	 * Complain if it is not there and do no more processing.
 	 */
-	rn = rnh->rnh_deladdr(info->rti_info[RTAX_DST],
-	    info->rti_info[RTAX_NETMASK], &rnh->head);
+	rn = rnh->rnh_deladdr(rt_key_const(rt), rt_mask_const(rt), &rnh->head);
 	if (rn == NULL)
 		return (ESRCH);
 
@@ -1084,21 +1086,16 @@ change_route(struct rib_head *rnh, struct rt_addrinfo *info,
  */
 static int
 add_route_nhop(struct rib_head *rnh, struct rtentry *rt,
-    struct rt_addrinfo *info, struct route_nhop_data *rnd,
-    struct rib_cmd_info *rc)
+    struct route_nhop_data *rnd, struct rib_cmd_info *rc)
 {
-	struct sockaddr *ndst, *netmask;
 	struct radix_node *rn;
 	int error = 0;
 
 	RIB_WLOCK_ASSERT(rnh);
 
-	ndst = (struct sockaddr *)rt_key(rt);
-	netmask = info->rti_info[RTAX_NETMASK];
-
 	rt->rt_nhop = rnd->rnd_nhop;
 	rt->rt_weight = rnd->rnd_weight;
-	rn = rnh->rnh_addaddr(ndst, netmask, &rnh->head, rt->rt_nodes);
+	rn = rnh->rnh_addaddr(rt_key(rt), rt_mask_const(rt), &rnh->head, rt->rt_nodes);
 
 	if (rn != NULL) {
 		if (!NH_IS_NHGRP(rnd->rnd_nhop) && nhop_get_expire(rnd->rnd_nhop))
@@ -1129,8 +1126,7 @@ add_route_nhop(struct rib_head *rnh, struct rtentry *rt,
  */
 int
 change_route_nhop(struct rib_head *rnh, struct rtentry *rt,
-    struct rt_addrinfo *info, struct route_nhop_data *rnd,
-    struct rib_cmd_info *rc)
+    struct route_nhop_data *rnd, struct rib_cmd_info *rc)
 {
 	struct nhop_object *nh_orig;
 
@@ -1146,12 +1142,9 @@ change_route_nhop(struct rib_head *rnh, struct rtentry *rt,
 			tmproutes_update(rnh, rt, rnd->rnd_nhop);
 	} else {
 		/* Route deletion requested. */
-		struct sockaddr *ndst, *netmask;
 		struct radix_node *rn;
 
-		ndst = (struct sockaddr *)rt_key(rt);
-		netmask = info->rti_info[RTAX_NETMASK];
-		rn = rnh->rnh_deladdr(ndst, netmask, &rnh->head);
+		rn = rnh->rnh_deladdr(rt_key_const(rt), rt_mask_const(rt), &rnh->head);
 		if (rn == NULL)
 			return (ESRCH);
 		rt = RNTORT(rn);
@@ -1203,7 +1196,7 @@ change_route_conditional(struct rib_head *rnh, struct rtentry *rt,
 
 	if (rt_new == NULL) {
 		if (rnd_orig->rnd_nhop == NULL)
-			error = add_route_nhop(rnh, rt, info, rnd_new, rc);
+			error = add_route_nhop(rnh, rt, rnd_new, rc);
 		else {
 			/*
 			 * Prefix does not exist, which was not our assumption.
@@ -1220,7 +1213,7 @@ change_route_conditional(struct rib_head *rnh, struct rtentry *rt,
 			 * Nhop/mpath group hasn't changed. Flip
 			 * to the new precalculated one and return
 			 */
-			error = change_route_nhop(rnh, rt_new, info, rnd_new, rc);
+			error = change_route_nhop(rnh, rt_new, rnd_new, rc);
 		} else {
 			/* Update and retry */
 			rnd_orig->rnd_nhop = rt_new->rt_nhop;
diff --git a/sys/net/route/route_var.h b/sys/net/route/route_var.h
index 60891026c00a..2998c51b608d 100644
--- a/sys/net/route/route_var.h
+++ b/sys/net/route/route_var.h
@@ -220,8 +220,7 @@ void tmproutes_destroy(struct rib_head *rh);
 /* route_ctl.c */
 struct route_nhop_data;
 int change_route_nhop(struct rib_head *rnh, struct rtentry *rt,
-    struct rt_addrinfo *info, struct route_nhop_data *rnd,
-    struct rib_cmd_info *rc);
+    struct route_nhop_data *rnd, struct rib_cmd_info *rc);
 int change_route_conditional(struct rib_head *rnh, struct rtentry *rt,
     struct rt_addrinfo *info, struct route_nhop_data *nhd_orig,
     struct route_nhop_data *nhd_new, struct rib_cmd_info *rc);