nuttx/drivers/mkrd.c

103 lines
3.7 KiB
C

/****************************************************************************
* drivers/mkrd.c
*
* Copyright (C) 2019 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 <nuttx/kmalloc.h>
#include <nuttx/drivers/ramdisk.h>
#ifdef CONFIG_DRVR_MKRD
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: mkrd
*
* Description:
* This is a wrapper function around ramdisk_register. It combines the
* necessary operations to create a RAM disk into a single callable
* function. Memory for the RAM disk is allocated, appropriated, from
* the kernel heap (in build modes where there is a distinct kernel heap).
*
* Input Parameters:
* minor: Selects suffix of device named /dev/ramN, N={1,2,3...}
* nsectors: Number of sectors on device
* sectize: The size of one sector
* rdflags: See RDFLAG_* definitions. Typically
* RDFLAG_WRENABLED | RDFLAG_FUNLINK
*
* Returned Value:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
int mkrd(int minor, uint32_t nsectors, uint16_t sectsize, uint8_t rdflags)
{
FAR uint8_t *buffer;
int ret;
/* Allocate the memory backing up the ramdisk from the kernel heap */
buffer = (FAR uint8_t *)kmm_malloc(sectsize * nsectors);
if (buffer == NULL)
{
return -ENOMEM;
}
#ifdef CONFIG_DEBUG_INFO
memset(buffer, 0, sectsize * nsectors);
#endif
finfo("RAMDISK at %p\n", buffer);
/* Then register the ramdisk */
ret = ramdisk_register(minor, buffer, nsectors, sectsize, rdflags);
if (ret < 0)
{
ferr("ERROR: ramdisk_register() failed: %d\n", ret);
free(buffer);
}
return ret;
}
#endif /* CONFIG_DRVR_MKRD */