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#ident "$Id$"
/* ----------------------------------------------------------------------- *
*
* Copyright 2000-2001 H. Peter Anvin - All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, Inc.,
* 59 Temple Place Ste 330, Boston MA 02111-1307, USA, version 2.1,
* incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/*
* zalloc.c
*
* Allocate zero-initialized memory. Try to be efficient if the area is
* large.
*
*/
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/mman.h>
#include "lpsm.h"
#include "internals.h"
void *lpsm_zalloc(size_t size)
{
void *ptr, *mv;
int xbit, obit, rorder;
int order = BUDDY_ORDER_MIN;
if ( size > AH->slab[0].size ) {
while ( size > ((size_t)1 << order) )
order++;
xbit = lpsm_malloc_buddy_xbit(order);
if ( !xbit ) {
errno = ENOMEM;
return NULL;
} else {
rorder = AH->arena_size_lg2 - order;
obit = 1 << rorder;
ptr = (void *)((char *)AH->data_start +
((uintptr_t)(xbit-obit) << order));
if ( (uintptr_t)ptr & (PM->pagesize-1) ||
order < PM->pageshift ) {
memset(ptr, 0, size); /* Misaligned or too small */
} else {
size = (size_t)1 << order; /* "Real" size */
/* Do an anonymous mmap() over the affected area */
mv = mmap(ptr, size, PROT_READ|PROT_WRITE,
MAP_FIXED|MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
if ( mv != ptr ) {
memset(ptr, 0, size);
} else {
/* Mark dirty */
memset(PM->pageinfo + ((ptr-PM->arena) >> PM->pageshift),
page_dirty, size >> PM->pageshift);
}
}
}
} else {
ptr = lpsm_malloc_slab(size);
if ( ptr )
memset(ptr, 0, size);
}
return ptr;
}
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