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Merge "init: do not fork before doing (u)mount_all()"

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Tom Cherry 2019-04-18 00:34:03 +00:00 • committed by Gerrit Code Review
commit fc1749280c
1 changed files with 14 additions and 80 deletions
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94
init/builtins.cpp
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@ -451,78 +451,6 @@ static void import_late(const std::vector<std::string>& args, size_t start_index
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 @@ static Result<Success> do_mount_all(const BuiltinArguments& args) {
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 @@ static Result<Success> do_mount_all(const BuiltinArguments& args) {
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 @@ static Result<Success> do_mount_all(const BuiltinArguments& args) {
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 @@ static Result<Success> do_mount_all(const BuiltinArguments& args) {
/* 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();
}