Merge "overlayfs: use overlayfs for f2fs readonly mode"
diff --git a/fs_mgr/fs_mgr_overlayfs.cpp b/fs_mgr/fs_mgr_overlayfs.cpp
index 6213aeb..c7f3343 100644
--- a/fs_mgr/fs_mgr_overlayfs.cpp
+++ b/fs_mgr/fs_mgr_overlayfs.cpp
@@ -200,6 +200,24 @@
return (info.feat_ro_compat & EXT4_FEATURE_RO_COMPAT_SHARED_BLOCKS) != 0;
}
+#define F2FS_SUPER_OFFSET 1024
+#define F2FS_FEATURE_OFFSET 2180
+#define F2FS_FEATURE_RO 0x4000
+bool fs_mgr_is_read_only_f2fs(const std::string& dev) {
+ if (!fs_mgr_is_f2fs(dev)) return false;
+
+ android::base::unique_fd fd(open(dev.c_str(), O_RDONLY | O_CLOEXEC));
+ if (fd < 0) return false;
+
+ __le32 feat;
+ if ((TEMP_FAILURE_RETRY(lseek64(fd, F2FS_SUPER_OFFSET + F2FS_FEATURE_OFFSET, SEEK_SET)) < 0) ||
+ (TEMP_FAILURE_RETRY(read(fd, &feat, sizeof(feat))) < 0)) {
+ return false;
+ }
+
+ return (feat & cpu_to_le32(F2FS_FEATURE_RO)) != 0;
+}
+
bool fs_mgr_overlayfs_enabled(FstabEntry* entry) {
// readonly filesystem, can not be mount -o remount,rw
// for squashfs, erofs or if free space is (near) zero making such a remount
@@ -214,6 +232,11 @@
return true;
}
+ // f2fs read-only mode doesn't support remount,rw
+ if (fs_mgr_is_read_only_f2fs(entry->blk_device)) {
+ return true;
+ }
+
// check if ext4 de-dupe
auto has_shared_blocks = fs_mgr_has_shared_blocks(entry->mount_point, entry->blk_device);
if (!has_shared_blocks && (entry->mount_point == "/system")) {