1ac8057a1SPeter Maydell /*
2ac8057a1SPeter Maydell * memalign.c: Allocate an aligned memory region
3ac8057a1SPeter Maydell *
4ac8057a1SPeter Maydell * Copyright (c) 2003-2008 Fabrice Bellard
5ac8057a1SPeter Maydell * Copyright (c) 2010-2016 Red Hat, Inc.
6ac8057a1SPeter Maydell * Copyright (c) 2022 Linaro Ltd
7ac8057a1SPeter Maydell *
8ac8057a1SPeter Maydell * Permission is hereby granted, free of charge, to any person obtaining a copy
9ac8057a1SPeter Maydell * of this software and associated documentation files (the "Software"), to deal
10ac8057a1SPeter Maydell * in the Software without restriction, including without limitation the rights
11ac8057a1SPeter Maydell * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12ac8057a1SPeter Maydell * copies of the Software, and to permit persons to whom the Software is
13ac8057a1SPeter Maydell * furnished to do so, subject to the following conditions:
14ac8057a1SPeter Maydell *
15ac8057a1SPeter Maydell * The above copyright notice and this permission notice shall be included in
16ac8057a1SPeter Maydell * all copies or substantial portions of the Software.
17ac8057a1SPeter Maydell *
18ac8057a1SPeter Maydell * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19ac8057a1SPeter Maydell * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20ac8057a1SPeter Maydell * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21ac8057a1SPeter Maydell * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22ac8057a1SPeter Maydell * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23ac8057a1SPeter Maydell * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24ac8057a1SPeter Maydell * THE SOFTWARE.
25ac8057a1SPeter Maydell */
26ac8057a1SPeter Maydell
27ac8057a1SPeter Maydell #include "qemu/osdep.h"
285c8c714aSPeter Maydell #include "qemu/host-utils.h"
29*5df022cfSPeter Maydell #include "qemu/memalign.h"
305c8c714aSPeter Maydell #include "trace.h"
315c8c714aSPeter Maydell
qemu_try_memalign(size_t alignment,size_t size)325c8c714aSPeter Maydell void *qemu_try_memalign(size_t alignment, size_t size)
335c8c714aSPeter Maydell {
345c8c714aSPeter Maydell void *ptr;
355c8c714aSPeter Maydell
365c8c714aSPeter Maydell if (alignment < sizeof(void*)) {
375c8c714aSPeter Maydell alignment = sizeof(void*);
385c8c714aSPeter Maydell } else {
395c8c714aSPeter Maydell g_assert(is_power_of_2(alignment));
405c8c714aSPeter Maydell }
415c8c714aSPeter Maydell
425c8c714aSPeter Maydell /*
435c8c714aSPeter Maydell * Handling of 0 allocations varies among the different
445c8c714aSPeter Maydell * platform APIs (for instance _aligned_malloc() will
455c8c714aSPeter Maydell * fail) -- ensure that we always return a valid non-NULL
465c8c714aSPeter Maydell * pointer that can be freed by qemu_vfree().
475c8c714aSPeter Maydell */
485c8c714aSPeter Maydell if (size == 0) {
495c8c714aSPeter Maydell size++;
505c8c714aSPeter Maydell }
515c8c714aSPeter Maydell #if defined(CONFIG_POSIX_MEMALIGN)
525c8c714aSPeter Maydell int ret;
535c8c714aSPeter Maydell ret = posix_memalign(&ptr, alignment, size);
545c8c714aSPeter Maydell if (ret != 0) {
555c8c714aSPeter Maydell errno = ret;
565c8c714aSPeter Maydell ptr = NULL;
575c8c714aSPeter Maydell }
585c8c714aSPeter Maydell #elif defined(CONFIG_ALIGNED_MALLOC)
595c8c714aSPeter Maydell ptr = _aligned_malloc(size, alignment);
6088454f84SPeter Maydell #elif defined(CONFIG_VALLOC)
615c8c714aSPeter Maydell ptr = valloc(size);
6288454f84SPeter Maydell #elif defined(CONFIG_MEMALIGN)
635c8c714aSPeter Maydell ptr = memalign(alignment, size);
6488454f84SPeter Maydell #else
6588454f84SPeter Maydell #error No function to allocate aligned memory available
665c8c714aSPeter Maydell #endif
675c8c714aSPeter Maydell trace_qemu_memalign(alignment, size, ptr);
685c8c714aSPeter Maydell return ptr;
695c8c714aSPeter Maydell }
70ac8057a1SPeter Maydell
qemu_memalign(size_t alignment,size_t size)71ac8057a1SPeter Maydell void *qemu_memalign(size_t alignment, size_t size)
72ac8057a1SPeter Maydell {
73ac8057a1SPeter Maydell void *p = qemu_try_memalign(alignment, size);
74ac8057a1SPeter Maydell if (p) {
75ac8057a1SPeter Maydell return p;
76ac8057a1SPeter Maydell }
77ac8057a1SPeter Maydell fprintf(stderr,
78ac8057a1SPeter Maydell "qemu_memalign: failed to allocate %zu bytes at alignment %zu: %s\n",
79ac8057a1SPeter Maydell size, alignment, strerror(errno));
80ac8057a1SPeter Maydell abort();
81ac8057a1SPeter Maydell }
821a11265dSPeter Maydell
qemu_vfree(void * ptr)831a11265dSPeter Maydell void qemu_vfree(void *ptr)
841a11265dSPeter Maydell {
851a11265dSPeter Maydell trace_qemu_vfree(ptr);
861a11265dSPeter Maydell #if !defined(CONFIG_POSIX_MEMALIGN) && defined(CONFIG_ALIGNED_MALLOC)
871a11265dSPeter Maydell /* Only Windows _aligned_malloc needs a special free function */
881a11265dSPeter Maydell _aligned_free(ptr);
891a11265dSPeter Maydell #else
901a11265dSPeter Maydell free(ptr);
911a11265dSPeter Maydell #endif
921a11265dSPeter Maydell }
93