platform_system_core/libmodprobe/libmodprobe_ext.cpp
Steve Muckle 18b981ea7c create libmodprobe, integrate into first_stage_init
Modprobe functionality is required both within first stage init and also
as a standalone binary. Create a library for this using and extending
the logic in modalias_handler.cpp.

First stage init will attempt to load modules from /lib/modules.

Bug: 129780532
Change-Id: Ie3582358fd839c2f64e1b386b30ed551a86aef5d
2019-06-18 13:24:56 -07:00

68 lines
2.1 KiB
C++

/*
* Copyright (C) 2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <sys/stat.h>
#include <sys/syscall.h>
#include <android-base/logging.h>
#include <android-base/unique_fd.h>
#include <modprobe/modprobe.h>
bool Modprobe::Insmod(const std::string& path_name) {
android::base::unique_fd fd(
TEMP_FAILURE_RETRY(open(path_name.c_str(), O_RDONLY | O_NOFOLLOW | O_CLOEXEC)));
if (fd == -1) {
LOG(ERROR) << "Could not open module '" << path_name << "'";
return false;
}
std::string options = "";
auto options_iter = module_options_.find(MakeCanonical(path_name));
if (options_iter != module_options_.end()) {
options = options_iter->second;
}
LOG(INFO) << "Loading module " << path_name << " with args \"" << options << "\"";
int ret = syscall(__NR_finit_module, fd.get(), options.c_str(), 0);
if (ret != 0) {
if (errno == EEXIST) {
// Module already loaded
return true;
}
LOG(ERROR) << "Failed to insmod '" << path_name << "' with args '" << options << "'";
return false;
}
LOG(INFO) << "Loaded kernel module " << path_name;
return true;
}
bool Modprobe::ModuleExists(const std::string& module_name) {
struct stat fileStat;
auto deps = GetDependencies(module_name);
if (deps.empty()) {
// missing deps can happen in the case of an alias
return false;
}
if (stat(deps.front().c_str(), &fileStat)) {
return false;
}
if (!S_ISREG(fileStat.st_mode)) {
return false;
}
return true;
}