auto_patch/common15-6.6/common/11_swift/0025-FS-overlayfs-Add-a-parameter-to-disable-overlayfs.patch

From d05008fdf683e82262fc510c73d8f471e8b20805 Mon Sep 17 00:00:00 2001
From: Shengken Lin <shengken.lin@amlogic.corp-partner.google.com>
Date: Tue, 3 Jun 2025 11:29:39 +0800
Subject: [PATCH] FS: overlayfs: Add a parameter to disable overlayfs

Bug: 422002934
Test: cat /sys/module/kernel/parameters/nooverlayfs

Change-Id: I5b8ed76af3c938aa08ba6a49dd6411b1808365eb
Signed-off-by: Shengken Lin <shengken.lin@amlogic.corp-partner.google.com>
---
 fs/overlayfs/super.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index a550f356cbd8..26f367596ca0 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -11,6 +11,7 @@
 #include <linux/mount.h>
 #include <linux/parser.h>
 #include <linux/module.h>
+#include <linux/moduleparam.h>
 #include <linux/statfs.h>
 #include <linux/seq_file.h>
 #include <linux/posix_acl_xattr.h>
@@ -26,6 +27,7 @@ MODULE_DESCRIPTION("Overlay filesystem");
 MODULE_LICENSE("GPL");
 MODULE_IMPORT_NS(ANDROID_GKI_VFS_EXPORT_ONLY);

+static bool nooverlayfs; /* Disable overlayfs */

 struct ovl_dir_cache;

@@ -1533,6 +1535,11 @@ static int __init ovl_init(void)
 {
 	int err;

+	if (nooverlayfs) {
+		pr_info("overlayfs is disabled\n");
+		return 0;
+	}
+
 	ovl_inode_cachep = kmem_cache_create("ovl_inode",
 					     sizeof(struct ovl_inode), 0,
 					     (SLAB_RECLAIM_ACCOUNT|
@@ -1556,6 +1563,9 @@ static int __init ovl_init(void)

 static void __exit ovl_exit(void)
 {
+	if (nooverlayfs)
+		return;
+
 	unregister_filesystem(&ovl_fs_type);

 	/*
@@ -1567,5 +1577,11 @@ static void __exit ovl_exit(void)
 	ovl_aio_request_cache_destroy();
 }

+#ifdef MODULE
+module_param(nooverlayfs, bool, 0444);
+#else
+core_param(nooverlayfs, nooverlayfs, bool, 0444);
+#endif
+
 module_init(ovl_init);
 module_exit(ovl_exit);
--
2.34.1