switched inotify_init1() to alloc_file()

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

fs/notify/inotify/inotify_user.c

@@ -659,12 +659,6 @@ SYSCALL_DEFINE1(inotify_init1, int, flags)
 	if (fd < 0)
 		return fd;
 
-	filp = get_empty_filp();
-	if (!filp) {
-		ret = -ENFILE;
-		goto out_put_fd;
-	}
-
 	user = get_current_user();
 	if (unlikely(atomic_read(&user->inotify_devs) >=
 			inotify_max_user_instances)) {
@@ -679,24 +673,25 @@ SYSCALL_DEFINE1(inotify_init1, int, flags)
 		goto out_free_uid;
 	}
 
-	filp->f_op = &inotify_fops;
-	filp->f_path.mnt = mntget(inotify_mnt);
-	filp->f_path.dentry = dget(inotify_mnt->mnt_root);
-	filp->f_mapping = filp->f_path.dentry->d_inode->i_mapping;
-	filp->f_mode = FMODE_READ;
+	atomic_inc(&user->inotify_devs);
+
+	filp = alloc_file(inotify_mnt, dget(inotify_mnt->mnt_root),
+			  FMODE_READ, &inotify_fops);
+	if (!filp)
+		goto Enfile;
+
 	filp->f_flags = O_RDONLY | (flags & O_NONBLOCK);
 	filp->private_data = group;
 
-	atomic_inc(&user->inotify_devs);
-
 	fd_install(fd, filp);
 
 	return fd;
 
+Enfile:
+	ret = -ENFILE;
+	atomic_dec(&user->inotify_devs);
 out_free_uid:
 	free_uid(user);
-	put_filp(filp);
-out_put_fd:
 	put_unused_fd(fd);
 	return ret;
 }