incubator-nuttx/drivers/mkrd.c

93 lines
3.0 KiB
C

/****************************************************************************
* drivers/mkrd.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <string.h>
#include <debug.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)
{
ferr("ERROR: kmm_malloc() failed: %d\n", ret);
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);
kmm_free(buffer);
}
return ret;
}
#endif /* CONFIG_DRVR_MKRD */