zephyr/drivers/disk/ramdisk.c

112 lines
2.5 KiB
C

/*
* Copyright (c) 2016 Intel Corporation.
* Copyright (c) 2021, Nordic Semiconductor ASA
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <string.h>
#include <zephyr/types.h>
#include <zephyr/drivers/disk.h>
#include <errno.h>
#include <zephyr/init.h>
#include <zephyr/device.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(ramdisk, CONFIG_RAMDISK_LOG_LEVEL);
#define RAMDISK_SECTOR_SIZE 512
#define RAMDISK_VOLUME_SIZE (CONFIG_DISK_RAM_VOLUME_SIZE * 1024)
#define RAMDISK_SECTOR_COUNT (RAMDISK_VOLUME_SIZE / RAMDISK_SECTOR_SIZE)
static uint8_t ramdisk_buf[RAMDISK_VOLUME_SIZE];
static void *lba_to_address(uint32_t lba)
{
return &ramdisk_buf[lba * RAMDISK_SECTOR_SIZE];
}
static int disk_ram_access_status(struct disk_info *disk)
{
return DISK_STATUS_OK;
}
static int disk_ram_access_init(struct disk_info *disk)
{
return 0;
}
static int disk_ram_access_read(struct disk_info *disk, uint8_t *buff,
uint32_t sector, uint32_t count)
{
uint32_t last_sector = sector + count;
if (last_sector < sector || last_sector > RAMDISK_SECTOR_COUNT) {
LOG_ERR("Sector %" PRIu32 " is outside the range %u",
last_sector, RAMDISK_SECTOR_COUNT);
return -EIO;
}
memcpy(buff, lba_to_address(sector), count * RAMDISK_SECTOR_SIZE);
return 0;
}
static int disk_ram_access_write(struct disk_info *disk, const uint8_t *buff,
uint32_t sector, uint32_t count)
{
uint32_t last_sector = sector + count;
if (last_sector < sector || last_sector > RAMDISK_SECTOR_COUNT) {
LOG_ERR("Sector %" PRIu32 " is outside the range %u",
last_sector, RAMDISK_SECTOR_COUNT);
return -EIO;
}
memcpy(lba_to_address(sector), buff, count * RAMDISK_SECTOR_SIZE);
return 0;
}
static int disk_ram_access_ioctl(struct disk_info *disk, uint8_t cmd, void *buff)
{
switch (cmd) {
case DISK_IOCTL_CTRL_SYNC:
break;
case DISK_IOCTL_GET_SECTOR_COUNT:
*(uint32_t *)buff = RAMDISK_SECTOR_COUNT;
break;
case DISK_IOCTL_GET_SECTOR_SIZE:
*(uint32_t *)buff = RAMDISK_SECTOR_SIZE;
break;
case DISK_IOCTL_GET_ERASE_BLOCK_SZ:
*(uint32_t *)buff = 1U;
break;
default:
return -EINVAL;
}
return 0;
}
static const struct disk_operations ram_disk_ops = {
.init = disk_ram_access_init,
.status = disk_ram_access_status,
.read = disk_ram_access_read,
.write = disk_ram_access_write,
.ioctl = disk_ram_access_ioctl,
};
static struct disk_info ram_disk = {
.name = CONFIG_DISK_RAM_VOLUME_NAME,
.ops = &ram_disk_ops,
};
static int disk_ram_init(void)
{
return disk_access_register(&ram_disk);
}
SYS_INIT(disk_ram_init, APPLICATION, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);