commit d96c6b8e881054de1eb38ac87612b975ec4aaf27
author terryguan <terryguan@google.com> Fri Aug 16 14:27:23 2024 -0700
committer terryguan <terryguan@google.com> Tue Aug 27 09:37:25 2024 -0700
tree 9eaecb3adbe9ad1f75f012d24aaf4ad7f9549952
parent 6d85bb3ef53c75b9a91424da48f11f2153e90474

Add resume from hibernation in first stage init

If bootconfig hibernation_resume_device is present in boot config, then
we write that value to /sys/power/resume

Bug: 339688542
Test: Check resume from hibernation/boots with/without config present
Change-Id: I1a9bf63af4dab07e494740722898c1aba33c00b5

fs_mgr/libfstab/fstab_priv.h

diff --git a/fs_mgr/libfstab/fstab_priv.h b/fs_mgr/libfstab/fstab_priv.h
index 5105da0..73cb175 100644
--- a/fs_mgr/libfstab/fstab_priv.h
+++ b/fs_mgr/libfstab/fstab_priv.h
@@ -39,9 +39,6 @@
 void ImportBootconfigFromString(const std::string& bootconfig,
                                 const std::function<void(std::string, std::string)>& fn);
 
-bool GetBootconfigFromString(const std::string& bootconfig, const std::string& key,
-                             std::string* out);
-
 void ImportKernelCmdlineFromString(const std::string& cmdline,
                                    const std::function<void(std::string, std::string)>& fn);
 

fs_mgr/libfstab/include/fstab/fstab.h

diff --git a/fs_mgr/libfstab/include/fstab/fstab.h b/fs_mgr/libfstab/include/fstab/fstab.h
index 1696daf..21fe017 100644
--- a/fs_mgr/libfstab/include/fstab/fstab.h
+++ b/fs_mgr/libfstab/include/fstab/fstab.h
@@ -153,5 +153,8 @@
 // Return the "other" slot for the given slot suffix.
 std::string OtherSlotSuffix(const std::string& suffix);
 
+bool GetBootconfigFromString(const std::string& bootconfig, const std::string& key,
+                             std::string* out);
+
 }  // namespace fs_mgr
 }  // namespace android

init/first_stage_init.cpp

diff --git a/init/first_stage_init.cpp b/init/first_stage_init.cpp
index bfe636b..e06a645 100644
--- a/init/first_stage_init.cpp
+++ b/init/first_stage_init.cpp
@@ -38,6 +38,7 @@
 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>
 #include <android/avf_cc_flags.h>
+#include <fs_mgr.h>
 #include <modprobe/modprobe.h>
 #include <private/android_filesystem_config.h>
 
@@ -303,6 +304,22 @@
     return BootMode::NORMAL_MODE;
 }
 
+static void MaybeResumeFromHibernation(const std::string& bootconfig) {
+    std::string hibernationResumeDevice;
+    android::fs_mgr::GetBootconfigFromString(bootconfig, "androidboot.hibernation_resume_device",
+                                             &hibernationResumeDevice);
+    if (!hibernationResumeDevice.empty()) {
+        android::base::unique_fd fd(open("/sys/power/resume", O_RDWR | O_CLOEXEC));
+        if (fd >= 0) {
+            if (!android::base::WriteStringToFd(hibernationResumeDevice, fd)) {
+                PLOG(ERROR) << "Failed to write to /sys/power/resume";
+            }
+        } else {
+            PLOG(ERROR) << "Failed to open /sys/power/resume";
+        }
+    }
+}
+
 static std::unique_ptr<FirstStageMount> CreateFirstStageMount(const std::string& cmdline) {
     auto ret = FirstStageMount::Create(cmdline);
     if (ret.ok()) {
@@ -442,6 +459,8 @@
                   << module_elapse_time.count() << " ms";
     }
 
+    MaybeResumeFromHibernation(bootconfig);
+
     std::unique_ptr<FirstStageMount> fsm;
 
     bool created_devices = false;