Support configuring additional partitions for Pre-reboot Dexopt.

This CL adds a system property
"dalvik.vm.pr_dexopt_additional_system_partitions" for this purpose.

Bug: 356966116
Test: atest art_standalone_dexopt_chroot_setup_tests
Change-Id: Ifa362173d8280bde162199138def8b0b46152281

3 files changed, 56 insertions, 14 deletions

diff --git a/dexopt_chroot_setup/dexopt_chroot_setup.cc b/dexopt_chroot_setup/dexopt_chroot_setup.cc
index 46858127c3..7a1467a149 100644
--- a/dexopt_chroot_setup/dexopt_chroot_setup.cc
+++ b/dexopt_chroot_setup/dexopt_chroot_setup.cc
@@ -34,6 +34,7 @@
 #include <string>
 #include <string_view>
 #include <system_error>
+#include <tuple>
 #include <vector>
 
 #include "aidl/com/android/server/art/BnDexoptChrootSetup.h"
@@ -66,6 +67,7 @@ namespace {
 
 using ::android::base::ConsumePrefix;
 using ::android::base::Error;
+using ::android::base::GetProperty;
 using ::android::base::Join;
 using ::android::base::make_scope_guard;
 using ::android::base::NoDestructor;
@@ -530,12 +532,25 @@ Result<void> DexoptChrootSetup::SetUpChroot(const std::optional<std::string>& ot
   OR_RETURN(CreateDir(CHROOT_DIR));
   LOG(INFO) << ART_FORMAT("Created '{}'", CHROOT_DIR);
 
-  std::vector<std::string> additional_system_partitions = {
-      "system_ext",
-      "vendor",
-      "product",
+  std::vector<std::tuple<std::string, std::string>> additional_system_partitions = {
+      {"system_ext", "/system_ext"},
+      {"vendor", "/vendor"},
+      {"product", "/product"},
   };
 
+  std::string partitions_from_sysprop =
+      GetProperty(kAdditionalPartitionsSysprop, /*default_value=*/"");
+  std::vector<std::string_view> partitions_from_sysprop_entries;
+  art::Split(partitions_from_sysprop, ',', &partitions_from_sysprop_entries);
+  for (std::string_view entry : partitions_from_sysprop_entries) {
+    std::vector<std::string_view> pair;
+    art::Split(entry, ':', &pair);
+    if (pair.size() != 2 || pair[0].empty() || pair[1].empty() || !pair[1].starts_with('/')) {
+      return Errorf("Malformed entry in '{}': '{}'", kAdditionalPartitionsSysprop, entry);
+    }
+    additional_system_partitions.emplace_back(std::string(pair[0]), std::string(pair[1]));
+  }
+
   if (!IsOtaUpdate(ota_slot)) {  // Mainline update
     OR_RETURN(BindMount("/", CHROOT_DIR));
     // Normally, we don't need to bind-mount "/system" because it's a part of the image mounted at
@@ -543,11 +558,11 @@ Result<void> DexoptChrootSetup::SetUpChroot(const std::optional<std::string>& ot
     // "/system", so we need to bind-mount "/system" to handle this case. On devices where readonly
     // partitions are not remounted, bind-mounting "/system" doesn't hurt.
     OR_RETURN(BindMount("/system", PathInChroot("/system")));
-    for (const std::string& partition : additional_system_partitions) {
+    for (const auto& [partition, mount_point] : additional_system_partitions) {
       // Some additional partitions are optional, but that's okay. The root filesystem (mounted at
       // `/`) has empty directories for additional partitions. If additional partitions don't exist,
       // we'll just be bind-mounting empty directories.
-      OR_RETURN(BindMount("/" + partition, PathInChroot("/" + partition)));
+      OR_RETURN(BindMount(mount_point, PathInChroot(mount_point)));
     }
   } else {
     CHECK(ota_slot.value() == "_a" || ota_slot.value() == "_b");
@@ -577,9 +592,9 @@ Result<void> DexoptChrootSetup::SetUpChroot(const std::optional<std::string>& ot
       OR_RETURN(BindMount("/postinstall", CHROOT_DIR));
     }
 
-    for (const std::string& partition : additional_system_partitions) {
+    for (const auto& [partition, mount_point] : additional_system_partitions) {
       OR_RETURN(Mount(GetBlockDeviceName(partition, ota_slot.value()),
-                      PathInChroot("/" + partition),
+                      PathInChroot(mount_point),
                       /*is_optional=*/true));
     }
   }
diff --git a/dexopt_chroot_setup/dexopt_chroot_setup.h b/dexopt_chroot_setup/dexopt_chroot_setup.h
index f362e057a6..a80b1f7a16 100644
--- a/dexopt_chroot_setup/dexopt_chroot_setup.h
+++ b/dexopt_chroot_setup/dexopt_chroot_setup.h
@@ -27,6 +27,12 @@
 namespace art {
 namespace dexopt_chroot_setup {
 
+// A comma-separated list, where each entry is a colon-separated pair of a partition name in the
+// super image and a mount point. E.g.,
+// some_partition_1:/some_mount_point_1,some_partition_2:/some_mount_point_2
+constexpr const char* kAdditionalPartitionsSysprop =
+    "dalvik.vm.pr_dexopt_additional_system_partitions";
+
 // A service that sets up the chroot environment for Pre-reboot Dexopt.
 class DexoptChrootSetup : public aidl::com::android::server::art::BnDexoptChrootSetup {
  public:
diff --git a/dexopt_chroot_setup/dexopt_chroot_setup_test.cc b/dexopt_chroot_setup/dexopt_chroot_setup_test.cc
index 51a41ebd6d..bbe0da352c 100644
--- a/dexopt_chroot_setup/dexopt_chroot_setup_test.cc
+++ b/dexopt_chroot_setup/dexopt_chroot_setup_test.cc
@@ -22,8 +22,10 @@
 #include <filesystem>
 #include <string>
 #include <string_view>
+#include <utility>
 
 #include "aidl/com/android/server/art/BnDexoptChrootSetup.h"
+#include "android-base/file.h"
 #include "android-base/properties.h"
 #include "android-base/result-gmock.h"
 #include "android-base/scopeguard.h"
@@ -41,7 +43,9 @@ namespace art {
 namespace dexopt_chroot_setup {
 namespace {
 
+using ::android::base::GetProperty;
 using ::android::base::ScopeGuard;
+using ::android::base::SetProperty;
 using ::android::base::WaitForProperty;
 using ::android::base::testing::HasError;
 using ::android::base::testing::HasValue;
@@ -78,20 +82,29 @@ class DexoptChrootSetupTest : public CommonArtTest {
       GTEST_SKIP() << "A real Pre-reboot Dexopt is running";
     }
 
-    ASSERT_TRUE(WaitForProperty("dev.bootcomplete", "1", /*relative_timeout=*/std::chrono::minutes(3)));
+    ASSERT_TRUE(
+        WaitForProperty("dev.bootcomplete", "1", /*relative_timeout=*/std::chrono::minutes(3)));
 
-    test_skipped = false;
+    test_skipped_ = false;
 
     scratch_dir_ = std::make_unique<ScratchDir>();
     scratch_path_ = scratch_dir_->GetPath();
     // Remove the trailing '/';
     scratch_path_.resize(scratch_path_.length() - 1);
+
+    partitions_sysprop_value_ = GetProperty(kAdditionalPartitionsSysprop, /*default_value=*/"");
+    ASSERT_TRUE(SetProperty(kAdditionalPartitionsSysprop, "odm:/odm,system_dlkm:/system_dlkm"));
+    partitions_sysprop_set_ = true;
   }
 
   void TearDown() override {
-    if (test_skipped) {
+    if (test_skipped_) {
       return;
     }
+    if (partitions_sysprop_set_ &&
+        !SetProperty(kAdditionalPartitionsSysprop, partitions_sysprop_value_)) {
+      LOG(ERROR) << ART_FORMAT("Failed to recover sysprop '{}'", kAdditionalPartitionsSysprop);
+    }
     scratch_dir_.reset();
     dexopt_chroot_setup_->tearDown(/*in_allowConcurrent=*/false);
     CommonArtTest::TearDown();
@@ -100,7 +113,9 @@ class DexoptChrootSetupTest : public CommonArtTest {
   std::shared_ptr<DexoptChrootSetup> dexopt_chroot_setup_;
   std::unique_ptr<ScratchDir> scratch_dir_;
   std::string scratch_path_;
-  bool test_skipped = true;
+  bool test_skipped_ = true;
+  std::string partitions_sysprop_value_;
+  bool partitions_sysprop_set_ = false;
 };
 
 TEST_F(DexoptChrootSetupTest, Run) {
@@ -110,6 +125,9 @@ TEST_F(DexoptChrootSetupTest, Run) {
       dexopt_chroot_setup_->setUp(/*in_otaSlot=*/std::nullopt, /*in_mapSnapshotsForOta=*/false));
   ASSERT_STATUS_OK(dexopt_chroot_setup_->init());
 
+  std::string mounts;
+  ASSERT_TRUE(android::base::ReadFileToString("/proc/mounts", &mounts, /*follow_symlinks=*/true));
+
   // Some important dirs that should be the same as outside.
   std::vector<const char*> same_dirs = {
       "/",
@@ -127,6 +145,8 @@ TEST_F(DexoptChrootSetupTest, Run) {
       "/sys/fs/cgroup",
       "/sys/fs/selinux",
       "/metadata",
+      "/odm",
+      "/system_dlkm",
   };
 
   for (const std::string& dir : same_dirs) {
@@ -134,8 +154,9 @@ TEST_F(DexoptChrootSetupTest, Run) {
     ASSERT_EQ(stat(dir.c_str(), &st_outside), 0);
     struct stat st_inside;
     ASSERT_EQ(stat(PathInChroot(dir).c_str(), &st_inside), 0);
-    EXPECT_EQ(st_outside.st_dev, st_inside.st_dev);
-    EXPECT_EQ(st_outside.st_ino, st_inside.st_ino);
+    EXPECT_EQ(std::make_pair(st_outside.st_dev, st_outside.st_ino),
+              std::make_pair(st_inside.st_dev, st_inside.st_ino))
+        << ART_FORMAT("Unexpected different directory in chroot: '{}'\n", dir) << mounts;
   }
 
   // Some important dirs that are expected to be writable.