init: do not fork before doing (u)mount_all()
A fork() was historically added in case of fs_mgr crashing or leaking
memory, but this should not be the case with fs_mgr, and a fork() only
hides any such problem, instead of allowing us to address it
directly.
Test: boot
Change-Id: If7ee4807757048258a6ea9a79a24cebbacc530cc
diff --git a/init/builtins.cpp b/init/builtins.cpp
index fc75072..06da4be 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -451,78 +451,6 @@
if (false) DumpState();
}
-/* handle_fstab
- *
- * Read the given fstab file and execute func on it.
- */
-static Result<int> handle_fstab(const std::string& fstabfile, std::function<int(Fstab*)> func) {
- /*
- * Call fs_mgr_[u]mount_all() to [u]mount all filesystems. We fork(2) and
- * do the call in the child to provide protection to the main init
- * process if anything goes wrong (crash or memory leak), and wait for
- * the child to finish in the parent.
- */
- pid_t pid = fork();
- if (pid > 0) {
- /* Parent. Wait for the child to return */
- int status;
- int wp_ret = TEMP_FAILURE_RETRY(waitpid(pid, &status, 0));
- if (wp_ret == -1) {
- // Unexpected error code. We will continue anyway.
- PLOG(WARNING) << "waitpid failed";
- }
-
- if (WIFEXITED(status)) {
- return WEXITSTATUS(status);
- } else {
- return Error() << "child aborted";
- }
- } else if (pid == 0) {
- /* child, call fs_mgr_[u]mount_all() */
-
- // So we can always see what fs_mgr_[u]mount_all() does.
- // Only needed if someone explicitly changes the default log level in their init.rc.
- android::base::ScopedLogSeverity info(android::base::INFO);
-
- Fstab fstab;
- ReadFstabFromFile(fstabfile, &fstab);
-
- int child_ret = func(&fstab);
-
- _exit(child_ret);
- } else {
- return Error() << "fork() failed";
- }
-}
-
-/* mount_fstab
- *
- * Call fs_mgr_mount_all() to mount the given fstab
- */
-static Result<int> mount_fstab(const std::string& fstabfile, int mount_mode) {
- return handle_fstab(fstabfile, [mount_mode](Fstab* fstab) {
- int ret = fs_mgr_mount_all(fstab, mount_mode);
- if (ret == -1) {
- PLOG(ERROR) << "fs_mgr_mount_all returned an error";
- }
- return ret;
- });
-}
-
-/* umount_fstab
- *
- * Call fs_mgr_umount_all() to umount the given fstab
- */
-static Result<int> umount_fstab(const std::string& fstabfile) {
- return handle_fstab(fstabfile, [](Fstab* fstab) {
- int ret = fs_mgr_umount_all(fstab);
- if (ret != 0) {
- PLOG(ERROR) << "fs_mgr_umount_all returned " << ret;
- }
- return ret;
- });
-}
-
/* Queue event based on fs_mgr return code.
*
* code: return code of fs_mgr_mount_all
@@ -609,7 +537,7 @@
bool import_rc = true;
bool queue_event = true;
int mount_mode = MOUNT_MODE_DEFAULT;
- const auto& fstabfile = args[1];
+ const auto& fstab_file = args[1];
std::size_t path_arg_end = args.size();
const char* prop_post_fix = "default";
@@ -629,10 +557,12 @@
std::string prop_name = "ro.boottime.init.mount_all."s + prop_post_fix;
android::base::Timer t;
- auto mount_fstab_return_code = mount_fstab(fstabfile, mount_mode);
- if (!mount_fstab_return_code) {
- return Error() << "mount_fstab() failed " << mount_fstab_return_code.error();
+
+ Fstab fstab;
+ if (!ReadFstabFromFile(fstab_file, &fstab)) {
+ return Error() << "Could not read fstab";
}
+ auto mount_fstab_return_code = fs_mgr_mount_all(&fstab, mount_mode);
property_set(prop_name, std::to_string(t.duration().count()));
if (import_rc) {
@@ -643,7 +573,7 @@
if (queue_event) {
/* queue_fs_event will queue event based on mount_fstab return code
* and return processed return code*/
- auto queue_fs_result = queue_fs_event(*mount_fstab_return_code);
+ auto queue_fs_result = queue_fs_event(mount_fstab_return_code);
if (!queue_fs_result) {
return Error() << "queue_fs_event() failed: " << queue_fs_result.error();
}
@@ -654,9 +584,13 @@
/* umount_all <fstab> */
static Result<Success> do_umount_all(const BuiltinArguments& args) {
- auto umount_fstab_return_code = umount_fstab(args[1]);
- if (!umount_fstab_return_code) {
- return Error() << "umount_fstab() failed " << umount_fstab_return_code.error();
+ Fstab fstab;
+ if (!ReadFstabFromFile(args[1], &fstab)) {
+ return Error() << "Could not read fstab";
+ }
+
+ if (auto result = fs_mgr_umount_all(&fstab); result != 0) {
+ return Error() << "umount_fstab() failed " << result;
}
return Success();
}