/*
 * PASS (Power Aware System Service) - Memory Resource Driver
 *
 * Copyright (c) 2022 Samsung Electronics Co., Ltd.
 *
 * 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.
 */

/**
 * @file	resource-memory.c
 * @brief	TBD
 * @ingroup	TBD
 */

#include <glib.h>

#include <util/common.h>
#include <util/log.h>
#include <util/kernel.h>

#include <libsyscommon/resource-manager.h>
#include <libsyscommon/resource-type.h>

#include <resource-monitor/resource-monitor.h>

#define PROC_MEM_INFO_MEM_AVAILABLE "MemAvailable"
#define PROC_MEM_INFO_MEM_FREE "MemFree"
#define PROC_MEM_INFO_BUFFER "Buffers"
#define PROC_MEM_INFO_CACHED "Cached"
#define PROC_MEM_INFO_CMA_FREE "CmaFree"
#define PROC_MEM_INFO_SWAP_FREE "SwapFree"

static int memory_get_cma_total(u_int64_t *val)
{
	static u_int64_t cma_total = 0;
	int ret;

	if (!cma_total) {
		ret = kernel_get_memory_info("CmaTotal", &cma_total);
		if (ret < 0) {
			_E("failed to get system CMA total memory\n");
			return -EINVAL;
		}
	}

	*val = cma_total;

	return 0;
}

static int memory_get_swap_total(u_int64_t *val)
{
	static u_int64_t swap_total = 0;
	int ret;

	if (!swap_total) {
		ret = kernel_get_memory_info("SwapTotal", &swap_total);
		if (ret < 0) {
			_E("failed to get system SWAP total memory\n");
			return -EINVAL;
		}
	}

	*val = swap_total;

	return 0;
}

static int memory_get_memory_info(int resource_id,
				const struct syscommon_resman_resource_attribute *attr,
				void *data)
{
	u_int64_t *val = (u_int64_t *)data;
	int ret;

	if (resource_id < 0 || !attr || !data)
		return -EINVAL;

	switch (attr->id) {
	case MEMORY_ATTR_TOTAL:
		ret = kernel_get_memory_total(val);
		break;
	case MEMORY_ATTR_AVAILABLE:
		ret = kernel_get_memory_info(PROC_MEM_INFO_MEM_AVAILABLE, val);
		break;
	case MEMORY_ATTR_FREE:
		ret = kernel_get_memory_info(PROC_MEM_INFO_MEM_FREE, val);
		break;
	case MEMORY_ATTR_BUFFER:
		ret = kernel_get_memory_info(PROC_MEM_INFO_BUFFER, val);
		break;
	case MEMORY_ATTR_CACHED:
		ret = kernel_get_memory_info(PROC_MEM_INFO_CACHED, val);
		break;
	case MEMORY_ATTR_CMA_TOTAL:
		ret = memory_get_cma_total(val);
		break;
	case MEMORY_ATTR_CMA_FREE:
		ret = kernel_get_memory_info(PROC_MEM_INFO_CMA_FREE, val);
		break;
	case MEMORY_ATTR_SWAP_TOTAL:
		ret = memory_get_swap_total(val);
		break;
	case MEMORY_ATTR_SWAP_FREE:
		ret = kernel_get_memory_info(PROC_MEM_INFO_SWAP_FREE, val);
		break;
	default:
		_E("wrong memory resource attribute\n");
		ret = -EINVAL;
	}
	if (ret < 0)
		return -EINVAL;

	return 0;
}

static const struct syscommon_resman_resource_attribute memory_attrs[] = {
	{
		.name	= "MEMORY_ATTR_TOTAL",
		.id	= MEMORY_ATTR_TOTAL,
		.type	= SYSCOMMON_RESMAN_DATA_TYPE_UINT64,
		.flag	= SYSCOMMON_RESMAN_RESOURCE_ATTR_FLAG_PUBLIC,
		.ops	= {
			.get = memory_get_memory_info,
		},
	}, {
		.name	= "MEMORY_ATTR_AVAILABLE",
		.id	= MEMORY_ATTR_AVAILABLE,
		.type	= SYSCOMMON_RESMAN_DATA_TYPE_UINT64,
		.flag	= SYSCOMMON_RESMAN_RESOURCE_ATTR_FLAG_PUBLIC,
		.ops	= {
			.get = memory_get_memory_info,
		},
	}, {
		.name	= "MEMORY_ATTR_FREE",
		.id	= MEMORY_ATTR_FREE,
		.type	= SYSCOMMON_RESMAN_DATA_TYPE_UINT64,
		.flag	= SYSCOMMON_RESMAN_RESOURCE_ATTR_FLAG_PUBLIC,
		.ops	= {
			.get = memory_get_memory_info,
		}
	}, {
		.name	= "MEMORY_ATTR_BUFFER",
		.id	= MEMORY_ATTR_BUFFER,
		.type	= SYSCOMMON_RESMAN_DATA_TYPE_UINT64,
		.flag	= SYSCOMMON_RESMAN_RESOURCE_ATTR_FLAG_PUBLIC,
		.ops	= {
			.get = memory_get_memory_info,
		}
	}, {
		.name	= "MEMORY_ATTR_CACHED",
		.id	= MEMORY_ATTR_CACHED,
		.type	= SYSCOMMON_RESMAN_DATA_TYPE_UINT64,
		.flag	= SYSCOMMON_RESMAN_RESOURCE_ATTR_FLAG_PUBLIC,
		.ops	= {
			.get = memory_get_memory_info,
		}
	}, {
		.name	= "MEMORY_ATTR_CMA_TOTAL",
		.id	= MEMORY_ATTR_CMA_TOTAL,
		.type	= SYSCOMMON_RESMAN_DATA_TYPE_UINT64,
		.flag	= SYSCOMMON_RESMAN_RESOURCE_ATTR_FLAG_PUBLIC,
		.ops	= {
			.get = memory_get_memory_info,
		}
	}, {
		.name	= "MEMORY_ATTR_CMA_FREE",
		.id	= MEMORY_ATTR_CMA_FREE,
		.type	= SYSCOMMON_RESMAN_DATA_TYPE_UINT64,
		.flag	= SYSCOMMON_RESMAN_RESOURCE_ATTR_FLAG_PUBLIC,
		.ops	= {
			.get = memory_get_memory_info,
		}
	}, {
		.name	= "MEMORY_ATTR_SWAP_TOTAL",
		.id	= MEMORY_ATTR_SWAP_TOTAL,
		.type	= SYSCOMMON_RESMAN_DATA_TYPE_UINT64,
		.flag	= SYSCOMMON_RESMAN_RESOURCE_ATTR_FLAG_PUBLIC,
		.ops	= {
			.get = memory_get_memory_info,
		}
	}, {
		.name	= "MEMORY_ATTR_SWAP_FREE",
		.id	= MEMORY_ATTR_SWAP_FREE,
		.type	= SYSCOMMON_RESMAN_DATA_TYPE_UINT64,
		.flag	= SYSCOMMON_RESMAN_RESOURCE_ATTR_FLAG_PUBLIC,
		.ops	= {
			.get = memory_get_memory_info,
		}
	},
};

static const struct syscommon_resman_resource_driver memory_resource_driver = {
	.name		= "MEMORY",
	.type		= RESOURCE_TYPE_MEMORY,
	.flag		= SYSCOMMON_RESMAN_RESOURCE_DRIVER_FLAG_COUNT_ONLY_ONE,
	.attrs		= memory_attrs,
	.num_attrs	= ARRAY_SIZE(memory_attrs),
};
SYSCOMMON_RESMAN_RESOURCE_DRIVER_REGISTER(&memory_resource_driver)