memfd: add hugetlbsize argument

Learn to specificy hugetlb size as qemu_memfd_create() argument.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180201132757.23063-4-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Marc-André Lureau 2018-02-01 14:27:53 +01:00 committed by Paolo Bonzini
parent c5b2a9e078
commit 2ef8c0c99b
2 changed files with 19 additions and 5 deletions

View file

@ -17,7 +17,7 @@
#endif
int qemu_memfd_create(const char *name, size_t size, bool hugetlb,
unsigned int seals, Error **errp);
uint64_t hugetlbsize, unsigned int seals, Error **errp);
void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
int *fd, Error **errp);
void qemu_memfd_free(void *ptr, size_t size, int fd);

View file

@ -29,6 +29,7 @@
#include "qapi/error.h"
#include "qemu/memfd.h"
#include "qemu/host-utils.h"
#if defined CONFIG_LINUX && !defined CONFIG_MEMFD
#include <sys/syscall.h>
@ -56,9 +57,22 @@ static int memfd_create(const char *name, unsigned int flags)
#define MFD_HUGETLB 0x0004U
#endif
#ifndef MFD_HUGE_SHIFT
#define MFD_HUGE_SHIFT 26
#endif
int qemu_memfd_create(const char *name, size_t size, bool hugetlb,
unsigned int seals, Error **errp)
uint64_t hugetlbsize, unsigned int seals, Error **errp)
{
int htsize = hugetlbsize ? ctz64(hugetlbsize) : 0;
if (htsize && 1 << htsize != hugetlbsize) {
error_setg(errp, "Hugepage size must be a power of 2");
return -1;
}
htsize = htsize << MFD_HUGE_SHIFT;
#ifdef CONFIG_LINUX
int mfd = -1;
unsigned int flags = MFD_CLOEXEC;
@ -68,8 +82,8 @@ int qemu_memfd_create(const char *name, size_t size, bool hugetlb,
}
if (hugetlb) {
flags |= MFD_HUGETLB;
flags |= htsize;
}
mfd = memfd_create(name, flags);
if (mfd < 0) {
goto err;
@ -104,11 +118,11 @@ void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
int *fd, Error **errp)
{
void *ptr;
int mfd = qemu_memfd_create(name, size, false, seals, NULL);
int mfd = qemu_memfd_create(name, size, false, 0, seals, NULL);
/* some systems have memfd without sealing */
if (mfd == -1) {
mfd = qemu_memfd_create(name, size, false, 0, NULL);
mfd = qemu_memfd_create(name, size, false, 0, 0, NULL);
}
if (mfd == -1) {