343 lines
11 KiB
C
343 lines
11 KiB
C
/****************************************************************************
|
|
* drivers/ramdisk.c
|
|
*
|
|
* Copyright (C) 2008-2009, 2011 Gregory Nutt. All rights reserved.
|
|
* Author: Gregory Nutt <gnutt@nuttx.org>
|
|
*
|
|
* 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 NuttX 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 <sys/ioctl.h>
|
|
#include <stdint.h>
|
|
#include <stdbool.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <debug.h>
|
|
#include <errno.h>
|
|
|
|
#include <nuttx/kmalloc.h>
|
|
#include <nuttx/fs/fs.h>
|
|
#include <nuttx/ramdisk.h>
|
|
|
|
/****************************************************************************
|
|
* Private Definitions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Private Types
|
|
****************************************************************************/
|
|
|
|
struct rd_struct_s
|
|
{
|
|
uint32_t rd_nsectors; /* Number of sectors on device */
|
|
uint16_t rd_sectsize; /* The size of one sector */
|
|
#ifdef CONFIG_FS_WRITABLE
|
|
bool rd_writeenabled; /* true: can write to ram disk */
|
|
uint8_t *rd_buffer; /* RAM disk backup memory */
|
|
#else
|
|
const uint8_t *rd_buffer; /* ROM disk backup memory */
|
|
#endif
|
|
};
|
|
|
|
/****************************************************************************
|
|
* Private Function Prototypes
|
|
****************************************************************************/
|
|
|
|
static int rd_open(FAR struct inode *inode);
|
|
static int rd_close(FAR struct inode *inode);
|
|
static ssize_t rd_read(FAR struct inode *inode, unsigned char *buffer,
|
|
size_t start_sector, unsigned int nsectors);
|
|
#ifdef CONFIG_FS_WRITABLE
|
|
static ssize_t rd_write(FAR struct inode *inode, const unsigned char *buffer,
|
|
size_t start_sector, unsigned int nsectors);
|
|
#endif
|
|
static int rd_geometry(FAR struct inode *inode, struct geometry *geometry);
|
|
static int rd_ioctl(FAR struct inode *inode, int cmd, unsigned long arg);
|
|
|
|
/****************************************************************************
|
|
* Private Data
|
|
****************************************************************************/
|
|
|
|
static const struct block_operations g_bops =
|
|
{
|
|
rd_open, /* open */
|
|
rd_close, /* close */
|
|
rd_read, /* read */
|
|
#ifdef CONFIG_FS_WRITABLE
|
|
rd_write, /* write */
|
|
#else
|
|
NULL, /* write */
|
|
#endif
|
|
rd_geometry, /* geometry */
|
|
rd_ioctl /* ioctl */
|
|
};
|
|
|
|
/****************************************************************************
|
|
* Private Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: rd_open
|
|
*
|
|
* Description: Open the block device
|
|
*
|
|
****************************************************************************/
|
|
|
|
static int rd_open(FAR struct inode *inode)
|
|
{
|
|
fvdbg("Entry\n");
|
|
return OK;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: rd_closel
|
|
*
|
|
* Description: close the block device
|
|
*
|
|
****************************************************************************/
|
|
|
|
static int rd_close(FAR struct inode *inode)
|
|
{
|
|
fvdbg("Entry\n");
|
|
return OK;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: rd_read
|
|
*
|
|
* Description: Read the specified numer of sectors
|
|
*
|
|
****************************************************************************/
|
|
|
|
static ssize_t rd_read(FAR struct inode *inode, unsigned char *buffer,
|
|
size_t start_sector, unsigned int nsectors)
|
|
{
|
|
struct rd_struct_s *dev;
|
|
|
|
DEBUGASSERT(inode && inode->i_private);
|
|
dev = (struct rd_struct_s *)inode->i_private;
|
|
|
|
fvdbg("sector: %d nsectors: %d sectorsize: %d\n",
|
|
start_sector, dev->rd_sectsize, nsectors);
|
|
|
|
if (start_sector < dev->rd_nsectors &&
|
|
start_sector + nsectors <= dev->rd_nsectors)
|
|
{
|
|
fvdbg("Transfer %d bytes from %p\n",
|
|
nsectors * dev->rd_sectsize,
|
|
&dev->rd_buffer[start_sector * dev->rd_sectsize]);
|
|
|
|
memcpy(buffer,
|
|
&dev->rd_buffer[start_sector * dev->rd_sectsize],
|
|
nsectors * dev->rd_sectsize);
|
|
return nsectors;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: rd_write
|
|
*
|
|
* Description: Write the specified number of sectors
|
|
*
|
|
****************************************************************************/
|
|
|
|
#ifdef CONFIG_FS_WRITABLE
|
|
static ssize_t rd_write(FAR struct inode *inode, const unsigned char *buffer,
|
|
size_t start_sector, unsigned int nsectors)
|
|
{
|
|
struct rd_struct_s *dev;
|
|
|
|
DEBUGASSERT(inode && inode->i_private);
|
|
dev = (struct rd_struct_s *)inode->i_private;
|
|
|
|
fvdbg("sector: %d nsectors: %d sectorsize: %d\n",
|
|
start_sector, dev->rd_sectsize, nsectors);
|
|
|
|
if (!dev->rd_writeenabled)
|
|
{
|
|
return -EACCES;
|
|
}
|
|
else if (start_sector < dev->rd_nsectors &&
|
|
start_sector + nsectors <= dev->rd_nsectors)
|
|
{
|
|
fvdbg("Transfer %d bytes from %p\n",
|
|
nsectors * dev->rd_sectsize,
|
|
&dev->rd_buffer[start_sector * dev->rd_sectsize]);
|
|
|
|
memcpy(&dev->rd_buffer[start_sector * dev->rd_sectsize],
|
|
buffer,
|
|
nsectors * dev->rd_sectsize);
|
|
return nsectors;
|
|
}
|
|
|
|
return -EFBIG;
|
|
}
|
|
#endif
|
|
|
|
/****************************************************************************
|
|
* Name: rd_geometry
|
|
*
|
|
* Description: Return device geometry
|
|
*
|
|
****************************************************************************/
|
|
|
|
static int rd_geometry(FAR struct inode *inode, struct geometry *geometry)
|
|
{
|
|
struct rd_struct_s *dev;
|
|
|
|
fvdbg("Entry\n");
|
|
|
|
DEBUGASSERT(inode);
|
|
if (geometry)
|
|
{
|
|
dev = (struct rd_struct_s *)inode->i_private;
|
|
geometry->geo_available = true;
|
|
geometry->geo_mediachanged = false;
|
|
#ifdef CONFIG_FS_WRITABLE
|
|
geometry->geo_writeenabled = dev->rd_writeenabled;
|
|
#else
|
|
geometry->geo_writeenabled = false;
|
|
#endif
|
|
geometry->geo_nsectors = dev->rd_nsectors;
|
|
geometry->geo_sectorsize = dev->rd_sectsize;
|
|
|
|
fvdbg("available: true mediachanged: false writeenabled: %s\n",
|
|
geometry->geo_writeenabled ? "true" : "false");
|
|
fvdbg("nsectors: %d sectorsize: %d\n",
|
|
geometry->geo_nsectors, geometry->geo_sectorsize);
|
|
|
|
return OK;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: rd_ioctl
|
|
*
|
|
* Description: Return device geometry
|
|
*
|
|
****************************************************************************/
|
|
|
|
static int rd_ioctl(FAR struct inode *inode, int cmd, unsigned long arg)
|
|
{
|
|
struct rd_struct_s *dev ;
|
|
void **ppv = (void**)((uintptr_t)arg);
|
|
|
|
fvdbg("Entry\n");
|
|
|
|
/* Only one ioctl command is supported */
|
|
|
|
DEBUGASSERT(inode && inode->i_private);
|
|
if (cmd == BIOC_XIPBASE && ppv)
|
|
{
|
|
dev = (struct rd_struct_s *)inode->i_private;
|
|
*ppv = (void*)dev->rd_buffer;
|
|
|
|
fvdbg("ppv: %p\n", *ppv);
|
|
return OK;
|
|
}
|
|
|
|
return -ENOTTY;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: ramdisk_register
|
|
*
|
|
* Description: Register the a ramdisk
|
|
|
|
****************************************************************************/
|
|
|
|
#ifdef CONFIG_FS_WRITABLE
|
|
int ramdisk_register(int minor, uint8_t *buffer, uint32_t nsectors,
|
|
uint16_t sectsize, bool writeenabled)
|
|
#else
|
|
int romdisk_register(int minor, uint8_t *buffer, uint32_t nsectors,
|
|
uint16_t sectsize)
|
|
#endif
|
|
{
|
|
struct rd_struct_s *dev;
|
|
char devname[16];
|
|
int ret = -ENOMEM;
|
|
|
|
fvdbg("buffer: %p nsectors: %d sectsize: %d\n", buffer, nsectors, sectsize);
|
|
|
|
/* Sanity check */
|
|
|
|
#ifdef CONFIG_DEBUG
|
|
if (minor < 0 || minor > 255 || !buffer || !nsectors || !sectsize)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
#endif
|
|
|
|
/* Allocate a ramdisk device structure */
|
|
|
|
dev = (struct rd_struct_s *)kmalloc(sizeof(struct rd_struct_s));
|
|
if (dev)
|
|
{
|
|
/* Initialize the ramdisk device structure */
|
|
|
|
dev->rd_nsectors = nsectors; /* Number of sectors on device */
|
|
dev->rd_sectsize = sectsize; /* The size of one sector */
|
|
#ifdef CONFIG_FS_WRITABLE
|
|
dev->rd_writeenabled = writeenabled; /* true: can write to ram disk */
|
|
#endif
|
|
dev->rd_buffer = buffer; /* RAM disk backup memory */
|
|
|
|
/* Create a ramdisk device name */
|
|
|
|
snprintf(devname, 16, "/dev/ram%d", minor);
|
|
|
|
/* Inode private data is a reference to the ramdisk device stgructure */
|
|
|
|
ret = register_blockdriver(devname, &g_bops, 0, dev);
|
|
if (ret < 0)
|
|
{
|
|
fdbg("register_blockdriver failed: %d\n", -ret);
|
|
kfree(dev);
|
|
}
|
|
}
|
|
return ret;
|
|
}
|