diff --git a/sys/amd64/linux32/linux32_machdep.c b/sys/amd64/linux32/linux32_machdep.c
index 187ec15e0218..5b66d2f90fdf 100644
--- a/sys/amd64/linux32/linux32_machdep.c
+++ b/sys/amd64/linux32/linux32_machdep.c
@@ -645,7 +645,6 @@ linux_sigaltstack(struct thread *td, struct linux_sigaltstack_args *uap)
 int
 linux_ftruncate64(struct thread *td, struct linux_ftruncate64_args *args)
 {
-	struct ftruncate_args sa;
 
 #ifdef DEBUG
 	if (ldebug(ftruncate64))
@@ -653,9 +652,7 @@ linux_ftruncate64(struct thread *td, struct linux_ftruncate64_args *args)
 		    (intmax_t)args->length);
 #endif
 
-	sa.fd = args->fd;
-	sa.length = args->length;
-	return sys_ftruncate(td, &sa);
+	return (kern_ftruncate(td, args->fd, args->length));
 }
 
 int
diff --git a/sys/compat/freebsd32/freebsd32_misc.c b/sys/compat/freebsd32/freebsd32_misc.c
index b491a85a27c0..5482a2bec30d 100644
--- a/sys/compat/freebsd32/freebsd32_misc.c
+++ b/sys/compat/freebsd32/freebsd32_misc.c
@@ -1517,11 +1517,8 @@ freebsd32_truncate(struct thread *td, struct freebsd32_truncate_args *uap)
 int
 freebsd32_ftruncate(struct thread *td, struct freebsd32_ftruncate_args *uap)
 {
-	struct ftruncate_args ap;
 
-	ap.fd = uap->fd;
-	ap.length = PAIR32TO64(off_t,uap->length);
-	return (sys_ftruncate(td, &ap));
+	return (kern_ftruncate(td, uap->fd, PAIR32TO64(off_t, uap->length)));
 }
 
 #ifdef COMPAT_43
@@ -1623,11 +1620,8 @@ freebsd6_freebsd32_truncate(struct thread *td, struct freebsd6_freebsd32_truncat
 int
 freebsd6_freebsd32_ftruncate(struct thread *td, struct freebsd6_freebsd32_ftruncate_args *uap)
 {
-	struct ftruncate_args ap;
 
-	ap.fd = uap->fd;
-	ap.length = PAIR32TO64(off_t,uap->length);
-	return (sys_ftruncate(td, &ap));
+	return (kern_ftruncate(td, uap->fd, PAIR32TO64(off_t, uap->length)));
 }
 #endif /* COMPAT_FREEBSD6 */
 
diff --git a/sys/compat/linux/linux_file.c b/sys/compat/linux/linux_file.c
index b5126f4b6cbc..1079e9256115 100644
--- a/sys/compat/linux/linux_file.c
+++ b/sys/compat/linux/linux_file.c
@@ -939,15 +939,8 @@ linux_truncate64(struct thread *td, struct linux_truncate64_args *args)
 int
 linux_ftruncate(struct thread *td, struct linux_ftruncate_args *args)
 {
-	struct ftruncate_args /* {
-		int fd;
-		int pad;
-		off_t length;
-		} */ nuap;
 
-	nuap.fd = args->fd;
-	nuap.length = args->length;
-	return (sys_ftruncate(td, &nuap));
+	return (kern_ftruncate(td, args->fd, args->length));
 }
 
 int
diff --git a/sys/i386/linux/linux_machdep.c b/sys/i386/linux/linux_machdep.c
index 4b4b88609428..36e8df204334 100644
--- a/sys/i386/linux/linux_machdep.c
+++ b/sys/i386/linux/linux_machdep.c
@@ -611,7 +611,6 @@ linux_sigaltstack(struct thread *td, struct linux_sigaltstack_args *uap)
 int
 linux_ftruncate64(struct thread *td, struct linux_ftruncate64_args *args)
 {
-	struct ftruncate_args sa;
 
 #ifdef DEBUG
 	if (ldebug(ftruncate64))
@@ -619,9 +618,7 @@ linux_ftruncate64(struct thread *td, struct linux_ftruncate64_args *args)
 		    (intmax_t)args->length);
 #endif
 
-	sa.fd = args->fd;
-	sa.length = args->length;
-	return sys_ftruncate(td, &sa);
+	return (kern_ftruncate(td, args->fd, args->length));
 }
 
 int
diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c
index bcd12b4fa918..a04a44ad9081 100644
--- a/sys/kern/vfs_syscalls.c
+++ b/sys/kern/vfs_syscalls.c
@@ -3365,11 +3365,8 @@ freebsd6_truncate(struct thread *td, struct freebsd6_truncate_args *uap)
 int
 freebsd6_ftruncate(struct thread *td, struct freebsd6_ftruncate_args *uap)
 {
-	struct ftruncate_args ouap;
 
-	ouap.fd = uap->fd;
-	ouap.length = uap->length;
-	return (sys_ftruncate(td, &ouap));
+	return (kern_ftruncate(td, uap->fd, uap->length));
 }
 #endif