NFSv3: Clean up timespec encode

Simplify the struct iattr timestamp encoding by skipping the step of
an intermediate struct timespec.
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/nfs3xdr.c

@@ -456,9 +456,9 @@ static void zero_nfs_fh3(struct nfs_fh *fh)
  *		uint32	nseconds;
  *	};
  */
-static __be32 *xdr_encode_nfstime3(__be32 *p, const struct timespec *timep)
+static __be32 *xdr_encode_nfstime3(__be32 *p, const struct timespec64 *timep)
 {
-	*p++ = cpu_to_be32(timep->tv_sec);
+	*p++ = cpu_to_be32((u32)timep->tv_sec);
 	*p++ = cpu_to_be32(timep->tv_nsec);
 	return p;
 }
@@ -533,7 +533,6 @@ static __be32 *xdr_decode_nfstime3(__be32 *p, struct timespec64 *timep)
 static void encode_sattr3(struct xdr_stream *xdr, const struct iattr *attr,
 		struct user_namespace *userns)
 {
-	struct timespec ts;
 	u32 nbytes;
 	__be32 *p;
 
@@ -583,10 +582,8 @@ static void encode_sattr3(struct xdr_stream *xdr, const struct iattr *attr,
 		*p++ = xdr_zero;
 
 	if (attr->ia_valid & ATTR_ATIME_SET) {
-		struct timespec ts;
 		*p++ = xdr_two;
-		ts = timespec64_to_timespec(attr->ia_atime);
-		p = xdr_encode_nfstime3(p, &ts);
+		p = xdr_encode_nfstime3(p, &attr->ia_atime);
 	} else if (attr->ia_valid & ATTR_ATIME) {
 		*p++ = xdr_one;
 	} else
@@ -594,8 +591,7 @@ static void encode_sattr3(struct xdr_stream *xdr, const struct iattr *attr,
 
 	if (attr->ia_valid & ATTR_MTIME_SET) {
 		*p++ = xdr_two;
-		ts = timespec64_to_timespec(attr->ia_mtime);
-		xdr_encode_nfstime3(p, &ts);
+		xdr_encode_nfstime3(p, &attr->ia_mtime);
 	} else if (attr->ia_valid & ATTR_MTIME) {
 		*p = xdr_one;
 	} else

include/linux/nfs_xdr.h

@@ -869,7 +869,7 @@ struct nfs3_sattrargs {
 	struct nfs_fh *		fh;
 	struct iattr *		sattr;
 	unsigned int		guard;
-	struct timespec		guardtime;
+	struct timespec64	guardtime;
 };
 
 struct nfs3_diropargs {