/****************************************************************************
* up_blockdevice.c
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name Gregory Nutt nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <string.h>
#include <nuttx/fs.h>
#include <errno.h>
#include "up_internal.h"
/****************************************************************************
* Private Definitions
****************************************************************************/
#define NSECTORS 2048
#define LOGICAL_SECTOR_SIZE 512
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int up_open(FAR struct inode *inode);
static int up_close(FAR struct inode *inode);
static ssize_t up_read(FAR struct inode *inode, unsigned char *buffer,
size_t start_sector, unsigned int nsectors);
static ssize_t up_write(FAR struct inode *inode, const unsigned char *buffer,
size_t start_sector, unsigned int nsectors);
static int up_geometry(FAR struct inode *inode, struct geometry *geometry);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct block_operations g_bops =
{
.open = up_open,
.close = up_close,
.read = up_read,
.write = up_write,
.geometry = up_geometry,
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: up_open
*
* Description: Open the block device
*
****************************************************************************/
static int up_open(FAR struct inode *inode)
{
return OK;
}
/****************************************************************************
* Name: up_closel
*
* Description: close the block device
*
****************************************************************************/
static int up_close(FAR struct inode *inode)
{
return OK;
}
/****************************************************************************
* Name: up_read
*
* Description: Read the specified numer of sectors
*
****************************************************************************/
static ssize_t up_read(FAR struct inode *inode, unsigned char *buffer,
size_t start_sector, unsigned int nsectors)
{
if (inode)
{
char *src = inode->i_private;
if (src &&
start_sector < NSECTORS &&
start_sector + nsectors < NSECTORS)
{
memcpy(buffer,
&src[start_sector*LOGICAL_SECTOR_SIZE],
nsectors*LOGICAL_SECTOR_SIZE);
return nsectors;
}
}
return -EINVAL;
}
/****************************************************************************
* Name: up_write
*
* Description: Write the specified number of sectors
*
****************************************************************************/
static ssize_t up_write(FAR struct inode *inode, const unsigned char *buffer,
size_t start_sector, unsigned int nsectors)
{
if (inode)
{
char *dest = inode->i_private;
if (dest &&
start_sector < NSECTORS &&
start_sector + nsectors < NSECTORS)
{
memcpy(&dest[start_sector*LOGICAL_SECTOR_SIZE],
buffer,
nsectors*LOGICAL_SECTOR_SIZE);
return nsectors;
}
}
return -EINVAL;
}
/****************************************************************************
* Name: up_geometry
*
* Description: Return device geometry
*
****************************************************************************/
static int up_geometry(FAR struct inode *inode, struct geometry *geometry)
{
if (geometry)
{
geometry->geo_available = (inode->i_private != NULL);
geometry->geo_mediachanged = FALSE;
geometry->geo_writeenabled = TRUE;
geometry->geo_nsectors = NSECTORS;
geometry->geo_sectorsize = LOGICAL_SECTOR_SIZE;
return OK;
}
return -EINVAL;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_registerblockdevice
*
* Description: Register the simulated block device
****************************************************************************/
void up_registerblockdevice(void)
{
/* Inode private data is a filesystem image */
void *priv = (void*)up_deviceimage();
(void)register_blockdriver("/dev/blkdev", &g_bops, 0, priv);
}
