[readdir] constify ->actor

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/readdir.c

@@ -109,15 +109,14 @@ SYSCALL_DEFINE3(old_readdir, unsigned int, fd,
 {
 	int error;
 	struct fd f = fdget(fd);
-	struct readdir_callback buf;
+	struct readdir_callback buf = {
+		.ctx.actor = fillonedir,
+		.dirent = dirent
+	};
 
 	if (!f.file)
 		return -EBADF;
 
-	buf.ctx.actor = fillonedir;
-	buf.result = 0;
-	buf.dirent = dirent;
-
 	error = iterate_dir(f.file, &buf.ctx);
 	if (buf.result)
 		error = buf.result;
@@ -195,7 +194,11 @@ SYSCALL_DEFINE3(getdents, unsigned int, fd,
 {
 	struct fd f;
 	struct linux_dirent __user * lastdirent;
-	struct getdents_callback buf;
+	struct getdents_callback buf = {
+		.ctx.actor = filldir,
+		.count = count,
+		.current_dir = dirent
+	};
 	int error;
 
 	if (!access_ok(VERIFY_WRITE, dirent, count))
@@ -205,12 +208,6 @@ SYSCALL_DEFINE3(getdents, unsigned int, fd,
 	if (!f.file)
 		return -EBADF;
 
-	buf.current_dir = dirent;
-	buf.previous = NULL;
-	buf.count = count;
-	buf.error = 0;
-	buf.ctx.actor = filldir;
-
 	error = iterate_dir(f.file, &buf.ctx);
 	if (error >= 0)
 		error = buf.error;
@@ -277,7 +274,11 @@ SYSCALL_DEFINE3(getdents64, unsigned int, fd,
 {
 	struct fd f;
 	struct linux_dirent64 __user * lastdirent;
-	struct getdents_callback64 buf;
+	struct getdents_callback64 buf = {
+		.ctx.actor = filldir64,
+		.count = count,
+		.current_dir = dirent
+	};
 	int error;
 
 	if (!access_ok(VERIFY_WRITE, dirent, count))
@@ -287,12 +288,6 @@ SYSCALL_DEFINE3(getdents64, unsigned int, fd,
 	if (!f.file)
 		return -EBADF;
 
-	buf.current_dir = dirent;
-	buf.previous = NULL;
-	buf.count = count;
-	buf.error = 0;
-	buf.ctx.actor = filldir64;
-
 	error = iterate_dir(f.file, &buf.ctx);
 	if (error >= 0)
 		error = buf.error;