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/* SPDX-License-Identifier: BSD-2-Clause */
/*
* Copyright (c) 2012 Chris Johns (chrisj@rtems.org)
* Copyright (c) 2017 Gedare Bloom (gedare@rtems.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.
*
* 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <rtems/posix/mmanimpl.h>
#include <rtems/posix/shmimpl.h>
int munmap(void *addr, size_t len)
{
mmap_mapping *mapping;
rtems_chain_node *node;
/*
* Clear errno.
*/
errno = 0;
/*
* Length cannot be 0.
*/
if ( len == 0 ) {
errno = EINVAL;
return -1;
}
/* Check for illegal addresses. Watch out for address wrap. */
if (addr + len < addr) {
errno = EINVAL;
return -1;
}
mmap_mappings_lock_obtain();
node = rtems_chain_first (&mmap_mappings);
while ( !rtems_chain_is_tail( &mmap_mappings, node )) {
mapping = (mmap_mapping*) node;
if ( ( addr >= mapping->addr ) &&
( addr < ( mapping->addr + mapping->len )) ) {
rtems_chain_extract_unprotected( node );
/* FIXME: generally need a way to clean-up the backing object, but
* currently it only matters for MAP_SHARED shm objects. */
if ( mapping->shm != NULL ) {
POSIX_Shm_Attempt_delete(mapping->shm);
}
/* only free the mapping address for non-fixed mapping */
if (( mapping->flags & MAP_FIXED ) != MAP_FIXED ) {
/* only free the mapping address for non-shared mapping, because we
* re-use the mapping address across all of the shared mappings, and
* it is memory managed independently... */
if (( mapping->flags & MAP_SHARED ) != MAP_SHARED ) {
free( mapping->addr );
}
}
free( mapping );
break;
}
node = rtems_chain_next( node );
}
mmap_mappings_lock_release( );
return 0;
}
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