VFS: make vfs_fstat() use f[get|put]_light()

commit e994defb upstream.

Use the *_light() versions that properly avoid doing the file user count
updates when they are unnecessary.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[xr: Backported to 3.4: adjust function name]
Signed-off-by: Rui Xiang <rui.xiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/stat.c

@@ -57,12 +57,13 @@ EXPORT_SYMBOL(vfs_getattr);
 
 int vfs_fstat(unsigned int fd, struct kstat *stat)
 {
-	struct file *f = fget_raw(fd);
+	int fput_needed;
+	struct file *f = fget_light(fd, &fput_needed);
 	int error = -EBADF;
 
 	if (f) {
 		error = vfs_getattr(f->f_path.mnt, f->f_path.dentry, stat);
-		fput(f);
+		fput_light(f, fput_needed);
 	}
 	return error;
 }