unicorn/qemu/util/oslib-posix.c
Andreas Gustafsson 53dd82a7ca
oslib-posix: check for posix_memalign in configure script
Check for the presence of posix_memalign() in the configure script,
not using "defined(_POSIX_C_SOURCE) && !defined(__sun__)". This
lets qemu use posix_memalign() on NetBSD versions that have it,
instead of falling back to valloc() which is wasteful when the
required alignment is smaller than a page.

Backports commit 9bc5a7193fb422ee53187601eba577ee5d195522 from qemu
2018-03-08 08:56:35 -05:00

133 lines
3.5 KiB
C

/*
* os-posix-lib.c
*
* Copyright (c) 2003-2008 Fabrice Bellard
* Copyright (c) 2010 Red Hat, Inc.
*
* QEMU library functions on POSIX which are shared between QEMU and
* the QEMU tools.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#if defined(__linux__) && \
(defined(__x86_64__) || defined(__arm__) || defined(__aarch64__))
/* Use 2 MiB alignment so transparent hugepages can be used by KVM.
Valgrind does not support alignments larger than 1 MiB,
therefore we need special code which handles running on Valgrind. */
# define QEMU_VMALLOC_ALIGN (512 * 4096)
#elif defined(__linux__) && defined(__s390x__)
/* Use 1 MiB (segment size) alignment so gmap can be used by KVM. */
# define QEMU_VMALLOC_ALIGN (256 * 4096)
#elif defined(__linux__) && defined(__sparc__)
#include <sys/shm.h>
# define QEMU_VMALLOC_ALIGN MAX(getpagesize(), SHMLBA)
#else
# define QEMU_VMALLOC_ALIGN getpagesize()
#endif
#define HUGETLBFS_MAGIC 0x958458f6
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "unicorn/platform.h"
#include "sysemu/sysemu.h"
#include <sys/mman.h>
#include <libgen.h>
#include <setjmp.h>
#include <sys/signal.h>
#include "qemu/cutils.h"
#ifdef CONFIG_LINUX
#if !defined(__CYGWIN__)
#include <sys/syscall.h>
#endif
#include <sys/vfs.h>
#endif
#ifdef __FreeBSD__
#include <sys/sysctl.h>
#include <sys/user.h>
#endif
#include "qemu/mmap-alloc.h"
void *qemu_oom_check(void *ptr)
{
if (ptr == NULL) {
fprintf(stderr, "Failed to allocate memory: %s\n", strerror(errno));
abort();
}
return ptr;
}
void *qemu_try_memalign(size_t alignment, size_t size)
{
void *ptr;
if (alignment < sizeof(void*)) {
alignment = sizeof(void*);
}
#if defined(CONFIG_POSIX_MEMALIGN)
int ret;
ret = posix_memalign(&ptr, alignment, size);
if (ret != 0) {
errno = ret;
ptr = NULL;
}
#elif defined(CONFIG_BSD)
ptr = valloc(size);
#else
ptr = memalign(alignment, size);
#endif
return ptr;
}
void *qemu_memalign(size_t alignment, size_t size)
{
return qemu_oom_check(qemu_try_memalign(alignment, size));
}
/* alloc shared memory pages */
void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment)
{
size_t align = QEMU_VMALLOC_ALIGN;
void *ptr = qemu_ram_mmap(-1, size, align, false);
if (ptr == MAP_FAILED) {
return NULL;
}
if (alignment) {
*alignment = align;
}
return ptr;
}
void qemu_vfree(void *ptr)
{
free(ptr);
}
void qemu_anon_ram_free(void *ptr, size_t size)
{
qemu_ram_munmap(ptr, size);
}