incubator-nuttx/include/nuttx/pgalloc.h

213 lines
6.9 KiB
C

/****************************************************************************
* include/nuttx/pgalloc.h
*
* SPDX-License-Identifier: Apache-2.0
*
* 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.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_PGALLOC_H
#define __INCLUDE_NUTTX_PGALLOC_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#ifdef CONFIG_MM_PGALLOC
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* CONFIG_MM_PGALLOC - Enable page allocator support
* CONFIG_MM_PGSIZE - The page size. Must be one of {1024, 2048,
* 4096, 8192, or 16384}. This is easily extensible, but only those
* values are currently support.
* CONFIG_DEBUG_PGALLOC - Just like CONFIG_DEBUG_MM, but only generates
* output from the page allocation logic.
*
* Dependencies: CONFIG_ARCH_USE_MMU and CONFIG_GRAN
*/
#ifndef CONFIG_MM_PGALLOC_PGSIZE
# define CONFIG_MM_PGALLOC_PGSIZE 4096
#endif
#if CONFIG_MM_PGSIZE == 1024
# define MM_PGSIZE 1024
# define MM_PGSHIFT 10
#elif CONFIG_MM_PGSIZE == 2048
# define MM_PGSIZE 2048
# define MM_PGSHIFT 11
#elif CONFIG_MM_PGSIZE == 4096
# define MM_PGSIZE 4096
# define MM_PGSHIFT 12
#elif CONFIG_MM_PGSIZE == 8192
# define MM_PGSIZE 8192
# define MM_PGSHIFT 13
#elif CONFIG_MM_PGSIZE == 16384
# define MM_PGSIZE 16384
# define MM_PGSHIFT 14
#else
# error CONFIG_MM_PGSIZE not supported
#endif
#define MM_PGMASK (MM_PGSIZE - 1)
#define MM_PGALIGNDOWN(a) ((uintptr_t)(a) & ~MM_PGMASK)
#define MM_PGALIGNUP(a) (((uintptr_t)(a) + MM_PGMASK) & ~MM_PGMASK)
#define MM_NPAGES(s) (((uintptr_t)(s) + MM_PGMASK) >> MM_PGSHIFT)
#define MM_ISALIGNED(a) (((uintptr_t)(a) & MM_PGMASK) == 0)
/****************************************************************************
* Public Types
****************************************************************************/
/* Form in which the state of the granule allocator is returned, The size of
* each page is MM_PGSIZE/MM_PGSHIFT
*/
struct pginfo_s
{
uint16_t ntotal; /* The total number of pages */
uint16_t nfree; /* The number of free pages */
uint16_t mxfree; /* The longest sequence of free pages */
};
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Name: mm_pginitialize
*
* Description:
* Initialize the page allocator.
*
* Input Parameters:
* heap_start - The physical address of the start of memory region that
* will be used for the page allocator heap
* heap_size - The size (in bytes) of the memory region that will be used
* for the page allocator heap.
*
* Returned Value:
* None
*
****************************************************************************/
void mm_pginitialize(FAR void *heap_start, size_t heap_size);
/****************************************************************************
* Name: mm_pgreserve
*
* Description:
* Reserve memory in the page memory pool. This will reserve the pages
* that contain the start and end addresses plus all of the pages
* 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:
* start - The address of the beginning of the region to be reserved.
* size - The size of the region to be reserved
*
* Returned Value:
* None
*
****************************************************************************/
void mm_pgreserve(uintptr_t start, size_t size);
/****************************************************************************
* Name: mm_pgalloc
*
* Description:
* Allocate page memory from the page memory pool.
*
* Input Parameters:
* npages - The number of pages to allocate, each of size CONFIG_MM_PGSIZE.
*
* Returned Value:
* On success, a non-zero, physical address of the allocated page memory
* is returned. Zero is returned on failure. NOTE: This is an unmapped
* physical address and cannot be used until it is appropriately mapped.
*
****************************************************************************/
uintptr_t mm_pgalloc(unsigned int npages);
/****************************************************************************
* Name: mm_pgfree
*
* Description:
* Return page memory to the page memory pool.
*
* Input Parameters:
* paddr - A physical address to a page in the page memory pool previously
* allocated by mm_pgalloc.
* npages - The number of contiguous pages to be return to the page memory
* pool, beginning with the page at paddr;
*
* Returned Value:
* None
*
****************************************************************************/
void mm_pgfree(uintptr_t paddr, unsigned int npages);
/****************************************************************************
* Name: mm_pginfo
*
* Description:
* Return information about the page allocator.
*
* Input Parameters:
* handle - The handle previously returned by gran_initialize
* info - Memory location to return the gran allocator info.
*
* Returned Value:
* Zero (OK) is returned on success; a negated errno value is return on
* any failure.
*
****************************************************************************/
void mm_pginfo(FAR struct pginfo_s *info);
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* CONFIG_MM_PGALLOC */
#endif /* __INCLUDE_NUTTX_PGALLOC_H */