// ramdisk.cpp
// Author: Josh Holtrop
// Date: 08/20/04
// Modified: 05/11/05

#define _HOS_CPP_ _HOS_CPP_

extern "C"
{
#include "functions.h"
#include "mm/vmm.h"
#include "lang/lang.h"
}

#include "block/ramdisk.h"
#include "devices.h"

ramdisk_t *ramdisks[256];

minor_t ramdisk_new(u32_t size)
{
	int i;
	for (i = 0; i < 256; i++)
	{
		if (!ramdisks[i])
		{
			void *start;
			if (( start = kmalloc(size) ))
			{
				ramdisks[i] = (ramdisk_t *)New(ramdisk_t);
				ramdisks[i]->start = start;
				ramdisks[i]->size = size;
				return i;
			}
			return -2;
		}
	}
	return -1;
}

minor_t	ramdisk_register(void *ramdisk, u32_t size)
{
	int i;
	for (i = 0; i < 256; i++)
	{
		if (!ramdisks[i])
		{
			ramdisks[i] = (ramdisk_t *)New(ramdisk_t);
			ramdisks[i]->start = ramdisk;
			ramdisks[i]->size = size;
			return i;
		}
	}
	return -1;
}

int	ramdisk_remove(minor_t minor)
{
	if (ramdisks[minor])
	{
		kfree(ramdisks[minor]->start);
		kfree(ramdisks[minor]);
		ramdisks[minor] = NULL;
		return 0;
	}
	return -1;
}


int Ramdisk::block_read(minor_t minor, u32_t blockStart, u32_t blocks, void *buffer)
{
	if (!ramdisks[minor])
		return -1;
	if ((blockStart << BLOCK_SIZE_LOG) >= ramdisks[minor]->size)
		return -2;
	void *rdAddr = (void *)((u32_t)ramdisks[minor]->start + (blockStart << BLOCK_SIZE_LOG));
	u32_t copyLen = min(blocks << BLOCK_SIZE_LOG, ramdisks[minor]->size + (u32_t)ramdisks[minor]->start - (u32_t)rdAddr);
	memcpyd(buffer, rdAddr, copyLen >> 2);
	return copyLen;
}

int Ramdisk::block_write(minor_t minor, u32_t blockStart, u32_t blocks, void *buffer)
{
	if (!ramdisks[minor])
		return -1;
	if ((blockStart << BLOCK_SIZE_LOG) >= ramdisks[minor]->size)
		return -2;
	void *rdAddr = (void *)((u32_t)ramdisks[minor]->start + (blockStart << BLOCK_SIZE_LOG));
	u32_t copyLen = min(blocks << BLOCK_SIZE_LOG, ramdisks[minor]->size + (u32_t)ramdisks[minor]->start - (u32_t)rdAddr);
	memcpyd(rdAddr, buffer, copyLen >> 2);
	return copyLen;
}