support metamodule, remove built-in overlayfs mount

Co-authored-by: weishu <twsxtd@gmail.com>
Co-authored-by: YuKongA <70465933+YuKongA@users.noreply.github.com>
Co-authored-by: Ylarod <me@ylarod.cn>

userspace/meta-overlayfs/metamodule/customize.sh

@@ -0,0 +1,77 @@
+#!/system/bin/sh
+
+ui_print "- Detecting device architecture..."
+
+# Detect architecture using ro.product.cpu.abi
+ABI=$(grep_get_prop ro.product.cpu.abi)
+ui_print "- Detected ABI: $ABI"
+
+# Select the correct binary based on architecture
+case "$ABI" in
+    arm64-v8a)
+        ARCH_BINARY="meta-overlayfs-aarch64"
+        REMOVE_BINARY="meta-overlayfs-x86_64"
+        ui_print "- Selected architecture: ARM64"
+        ;;
+    x86_64)
+        ARCH_BINARY="meta-overlayfs-x86_64"
+        REMOVE_BINARY="meta-overlayfs-aarch64"
+        ui_print "- Selected architecture: x86_64"
+        ;;
+    *)
+        abort "! Unsupported architecture: $ABI"
+        ;;
+esac
+
+# Verify the selected binary exists
+if [ ! -f "$MODPATH/$ARCH_BINARY" ]; then
+    abort "! Binary not found: $ARCH_BINARY"
+fi
+
+ui_print "- Installing $ARCH_BINARY as meta-overlayfs"
+
+# Rename the selected binary to the generic name
+mv "$MODPATH/$ARCH_BINARY" "$MODPATH/meta-overlayfs" || abort "! Failed to rename binary"
+
+# Remove the unused binary
+rm -f "$MODPATH/$REMOVE_BINARY"
+
+# Ensure the binary is executable
+chmod 755 "$MODPATH/meta-overlayfs" || abort "! Failed to set permissions"
+
+ui_print "- Architecture-specific binary installed successfully"
+
+# Create ext4 image for module content storage
+IMG_FILE="$MODPATH/modules.img"
+MNT_DIR="$MODPATH/mnt"
+IMG_SIZE_MB=2048
+
+if [ ! -f "$IMG_FILE" ]; then
+    ui_print "- Creating 2GB ext4 image for module storage"
+
+    # Create sparse file (2GB logical size, 0 bytes actual)
+    truncate -s ${IMG_SIZE_MB}M "$IMG_FILE" || \
+        abort "! Failed to create image file"
+
+    # Format as ext4 with small journal (8MB) for safety with minimal overhead
+    /system/bin/mke2fs -t ext4 -J size=8 -F "$IMG_FILE" >/dev/null 2>&1 || \
+        abort "! Failed to format ext4 image"
+
+    ui_print "- Image created successfully (sparse file)"
+else
+    ui_print "- Existing image found, keeping it"
+fi
+
+# Mount image immediately for use
+ui_print "- Mounting image for immediate use..."
+mkdir -p "$MNT_DIR"
+if ! mountpoint -q "$MNT_DIR" 2>/dev/null; then
+    mount -t ext4 -o loop,rw,noatime "$IMG_FILE" "$MNT_DIR" || \
+        abort "! Failed to mount image"
+    ui_print "- Image mounted successfully"
+else
+    ui_print "- Image already mounted"
+fi
+
+ui_print "- Installation complete"
+ui_print "- Image is ready for module installations"