/****************************************************************************
* drivers/bch/bchdev_driver.c
*
* Copyright (C) 2008-2009 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 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.
*
****************************************************************************/
/****************************************************************************
* Compilation Switches
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <sched.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/fs.h>
#include <nuttx/ioctl.h>
#include "bch_internal.h"
/****************************************************************************
* Definitions
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int bch_open(FAR struct file *filp);
static int bch_close(FAR struct file *filp);
static ssize_t bch_read(FAR struct file *, FAR char *, size_t);
static ssize_t bch_write(FAR struct file *, FAR const char *, size_t);
static int bch_ioctl(FAR struct file *filp, int cmd, unsigned long arg);
/****************************************************************************
* Public Data
****************************************************************************/
const struct file_operations bch_fops =
{
bch_open, /* open */
bch_close, /* close */
bch_read, /* read */
bch_write, /* write */
0, /* seek */
bch_ioctl /* ioctl */
#ifndef CONFIG_DISABLE_POLL
, 0 /* poll */
#endif
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: bch_open
*
* Description: Open the block device
*
****************************************************************************/
static int bch_open(FAR struct file *filp)
{
FAR struct inode *inode = filp->f_inode;
FAR struct bchlib_s *bch;
DEBUGASSERT(inode && inode->i_private);
bch = (FAR struct bchlib_s *)inode->i_private;
/* Increment the reference count */
bchlib_semtake(bch);
if (bch->refs == MAX_OPENCNT)
{
return -EMFILE;
}
else
{
bch->refs++;
}
bchlib_semgive(bch);
return OK;
}
/****************************************************************************
* Name: bch_close
*
* Description: close the block device
*
****************************************************************************/
static int bch_close(FAR struct file *filp)
{
FAR struct inode *inode = filp->f_inode;
FAR struct bchlib_s *bch;
int ret = OK;
DEBUGASSERT(inode && inode->i_private);
bch = (FAR struct bchlib_s *)inode->i_private;
/* Flush any dirty pages remaining in the cache */
bchlib_semtake(bch);
(void)bchlib_flushsector(bch);
/* Decrement the reference count (I don't use bchlib_decref() because I
* want the entire close operation to be atomic wrt other driver operations.
*/
if (bch->refs == 0)
{
ret = -EIO;
}
else
{
bch->refs--;
}
bchlib_semgive(bch);
return ret;
}
/****************************************************************************
* Name:bch_read
****************************************************************************/
static ssize_t bch_read(FAR struct file *filp, FAR char *buffer, size_t len)
{
FAR struct inode *inode = filp->f_inode;
FAR struct bchlib_s *bch;
int ret;
DEBUGASSERT(inode && inode->i_private);
bch = (FAR struct bchlib_s *)inode->i_private;
bchlib_semtake(bch);
ret = bchlib_read(bch, buffer, filp->f_pos, len);
if (ret > 0)
{
filp->f_pos += len;
}
bchlib_semgive(bch);
return ret;
}
/****************************************************************************
* Name:bch_write
****************************************************************************/
static ssize_t bch_write(FAR struct file *filp, FAR const char *buffer, size_t len)
{
FAR struct inode *inode = filp->f_inode;
FAR struct bchlib_s *bch;
int ret = -EACCES;
DEBUGASSERT(inode && inode->i_private);
bch = (FAR struct bchlib_s *)inode->i_private;
if (!bch->readonly)
{
bchlib_semtake(bch);
ret = bchlib_write(bch, buffer, filp->f_pos, len);
if (ret > 0)
{
filp->f_pos += len;
}
bchlib_semgive(bch);
}
return ret;
}
/****************************************************************************
* Name: bch_ioctl
*
* Description: Return device geometry
*
****************************************************************************/
static int bch_ioctl(FAR struct file *filp, int cmd, unsigned long arg)
{
FAR struct inode *inode = filp->f_inode;
FAR struct bchlib_s *bch;
int ret = -ENOTTY;
DEBUGASSERT(inode && inode->i_private);
bch = (FAR struct bchlib_s *)inode->i_private;
if (cmd == DIOC_GETPRIV)
{
FAR struct bchlib_s **bchr = (FAR struct bchlib_s **)arg;
bchlib_semtake(bch);
if (!bchr && bch->refs < 255)
{
ret = -EINVAL;
}
else
{
bch->refs++;
*bchr = bch;
}
bchlib_semgive(bch);
}
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
