fs_mgr_overlayfs: Remove backing image if failed to allocate scratch
In CreateScratchOnData(), if backing image is allocated but failed to
map, then remove the backing image. Otherwise the unusable (unmappable)
image would waste a lot of space.
Bug: 255593675
Test: On device that don't support mapping gsid scratch,
run `adb remount` and then check that gsid scratch is removed and
scratch is allocated on super.
Test: TH run g3-app-compat-main
Change-Id: I0c01c2fd93a30ac0e46f4350c900403337530406
diff --git a/fs_mgr/fs_mgr_overlayfs.cpp b/fs_mgr/fs_mgr_overlayfs.cpp
index 6290057..5468fb8 100644
--- a/fs_mgr/fs_mgr_overlayfs.cpp
+++ b/fs_mgr/fs_mgr_overlayfs.cpp
@@ -462,6 +462,28 @@
return true;
}
+OverlayfsTeardownResult TeardownDataScratch(IImageManager* images,
+ const std::string& partition_name, bool was_mounted) {
+ if (!images) {
+ return OverlayfsTeardownResult::Error;
+ }
+ if (!images->DisableImage(partition_name)) {
+ return OverlayfsTeardownResult::Error;
+ }
+ if (was_mounted) {
+ // If overlayfs was mounted, don't bother trying to unmap since
+ // it'll fail and create error spam.
+ return OverlayfsTeardownResult::Busy;
+ }
+ if (!images->UnmapImageIfExists(partition_name)) {
+ return OverlayfsTeardownResult::Busy;
+ }
+ if (!images->DeleteBackingImage(partition_name)) {
+ return OverlayfsTeardownResult::Busy;
+ }
+ return OverlayfsTeardownResult::Ok;
+}
+
OverlayfsTeardownResult fs_mgr_overlayfs_teardown_scratch(const std::string& overlay,
bool* change) {
// umount and delete kScratchMountPoint storage if we have logical partitions
@@ -484,24 +506,9 @@
auto images = IImageManager::Open("remount", 10s);
if (images && images->BackingImageExists(partition_name)) {
- if (!images->DisableImage(partition_name)) {
- return OverlayfsTeardownResult::Error;
- }
- if (was_mounted) {
- // If overlayfs was mounted, don't bother trying to unmap since
- // it'll fail and create error spam.
- return OverlayfsTeardownResult::Busy;
- }
- if (!images->UnmapImageIfExists(partition_name)) {
- return OverlayfsTeardownResult::Busy;
- }
- if (!images->DeleteBackingImage(partition_name)) {
- return OverlayfsTeardownResult::Busy;
- }
-
// No need to check super partition, if we knew we had a scratch device
// in /data.
- return OverlayfsTeardownResult::Ok;
+ return TeardownDataScratch(images.get(), partition_name, was_mounted);
}
auto slot_number = fs_mgr_overlayfs_slot_number();
@@ -1103,6 +1110,8 @@
}
if (!images->MapImageDevice(partition_name, 10s, scratch_device)) {
LERROR << "could not map scratch image";
+ // If we cannot use this image, then remove it.
+ TeardownDataScratch(images.get(), partition_name, false /* was_mounted */);
return false;
}
return true;
@@ -1136,6 +1145,7 @@
if (CreateScratchOnData(scratch_device, partition_exists)) {
return true;
}
+ LOG(WARNING) << "Failed to allocate scratch on /data, fallback to use free space on super";
}
// If that fails, see if we can land on super.
if (CanUseSuperPartition(fstab)) {