You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
342 lines
11 KiB
342 lines
11 KiB
/**************************************************************************** |
|
* 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; |
|
}
|
|
|