Merge branch 'nlattr_align'

Nicolas Dichtel says:

====================
libnl: enhance API to ease 64bit alignment for attribute

Here is a proposal to add more helpers in the libnetlink to manage 64-bit
alignment issues.
Note that this series was only tested on x86 by tweeking
CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS and adding some traces.

The first patch adds helpers for 64bit alignment and other patches
use them.

We could also add helpers for nla_put_u64() and its variants if needed.

v1 -> v2:
 - remove patch #1
 - split patch #2 (now #1 and #2)
 - add nla_need_padding_for_64bit()
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 9 insertions, 21 deletions

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 4a47a9aceb1d..5ec059d52823 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1051,14 +1051,9 @@ static noinline_for_stack int rtnl_fill_stats(struct sk_buff *skb,
 {
 	struct rtnl_link_stats64 *sp;
 	struct nlattr *attr;
-	int err;
-
-	err = nla_align_64bit(skb, IFLA_PAD);
-	if (err)
-		return err;
 
-	attr = nla_reserve(skb, IFLA_STATS64,
-			   sizeof(struct rtnl_link_stats64));
+	attr = nla_reserve_64bit(skb, IFLA_STATS64,
+				 sizeof(struct rtnl_link_stats64), IFLA_PAD);
 	if (!attr)
 		return -EMSGSIZE;
 
@@ -3469,17 +3464,10 @@ static int rtnl_fill_statsinfo(struct sk_buff *skb, struct net_device *dev,
 
 	if (filter_mask & IFLA_STATS_FILTER_BIT(IFLA_STATS_LINK_64)) {
 		struct rtnl_link_stats64 *sp;
-		int err;
-
-		/* if necessary, add a zero length NOP attribute so that
-		 * IFLA_STATS_LINK_64 will be 64-bit aligned
-		 */
-		err = nla_align_64bit(skb, IFLA_STATS_UNSPEC);
-		if (err)
-			goto nla_put_failure;
 
-		attr = nla_reserve(skb, IFLA_STATS_LINK_64,
-				   sizeof(struct rtnl_link_stats64));
+		attr = nla_reserve_64bit(skb, IFLA_STATS_LINK_64,
+					 sizeof(struct rtnl_link_stats64),
+					 IFLA_STATS_UNSPEC);
 		if (!attr)
 			goto nla_put_failure;
 
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 395e2814a46d..21a38e296fe2 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -2104,7 +2104,7 @@ static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
 	mfcs.mfcs_packets = c->mfc_un.res.pkt;
 	mfcs.mfcs_bytes = c->mfc_un.res.bytes;
 	mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
-	if (nla_put(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs) < 0)
+	if (nla_put_64bit(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs, RTA_PAD) < 0)
 		return -EMSGSIZE;
 
 	rtm->rtm_type = RTN_MULTICAST;
@@ -2237,7 +2237,7 @@ static size_t mroute_msgsize(bool unresolved, int maxvif)
 		      + nla_total_size(0)	/* RTA_MULTIPATH */
 		      + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
 						/* RTA_MFC_STATS */
-		      + nla_total_size(sizeof(struct rta_mfc_stats))
+		      + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
 		;
 
 	return len;
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index a10e77103c88..bf678324fd52 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -2268,7 +2268,7 @@ static int __ip6mr_fill_mroute(struct mr6_table *mrt, struct sk_buff *skb,
 	mfcs.mfcs_packets = c->mfc_un.res.pkt;
 	mfcs.mfcs_bytes = c->mfc_un.res.bytes;
 	mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
-	if (nla_put(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs) < 0)
+	if (nla_put_64bit(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs, RTA_PAD) < 0)
 		return -EMSGSIZE;
 
 	rtm->rtm_type = RTN_MULTICAST;
@@ -2411,7 +2411,7 @@ static int mr6_msgsize(bool unresolved, int maxvif)
 		      + nla_total_size(0)	/* RTA_MULTIPATH */
 		      + maxvif * NLA_ALIGN(sizeof(struct rtnexthop))
 						/* RTA_MFC_STATS */
-		      + nla_total_size(sizeof(struct rta_mfc_stats))
+		      + nla_total_size_64bit(sizeof(struct rta_mfc_stats))
 		;
 
 	return len;