incubator-nuttx/mm/mm_granreserve.c

145 lines
5.1 KiB
C

/****************************************************************************
* mm/mm_granreserve.c
*
* Copyright (C) 2014 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 <assert.h>
#include <nuttx/gran.h>
#include "mm_gran.h"
#ifdef CONFIG_GRAN
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: gran_common_reserve
*
* Description:
* Reserve memory in the granule heap. This will reserve the granules
* that contain the start and end addresses plus all of the granules
* in between. This should be done early in the initialization sequence
* before any other allocations are made.
*
* Reserved memory can never be allocated (it can be freed however which
* essentially unreserves the memory).
*
* Input Parameters:
* priv - The granule heap state structure.
* start - The address of the beginning of the region to be reserved.
* size - The size of the region to be reserved
*
* Returned Value:
* None
*
****************************************************************************/
static inline void gran_common_reserve(FAR struct gran_s *priv,
uintptr_t start, size_t size)
{
if (size > 0)
{
uintptr_t mask = (1 << priv->log2gran) - 1;
uintptr_t end = start + size - 1;
unsigned int ngranules;
/* Get the aligned (down) start address and the aligned (up) end
* address
*/
start &= ~mask;
end = (end + mask) & ~mask;
/* Calculate the new size in granules */
ngranules = ((end - start) >> priv->log2gran) + 1;
/* And reserve the granules */
gran_mark_allocated(priv, start, ngranules);
}
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: gran_reserve
*
* Description:
* Reserve memory in the granule heap. This will reserve the granules
* that contain the start and end addresses plus all of the granules
* in between. This should be done early in the initialization sequence
* before any other allocations are made.
*
* Reserved memory can never be allocated (it can be freed however which
* essentially unreserves the memory).
*
* Input Parameters:
* handle - The handle previously returned by gran_initialize
* start - The address of the beginning of the region to be reserved.
* size - The size of the region to be reserved
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef CONFIG_GRAN_SINGLE
void gran_reserve(uintptr_t start, size_t size)
{
return gran_common_reserve(g_graninfo, start, size);
}
#else
void gran_reserve(GRAN_HANDLE handle, uintptr_t start, size_t size)
{
return gran_common_reserve((FAR struct gran_s *)handle, start, size);
}
#endif
#endif /* CONFIG_GRAN */