From 2ef8c0c99be7ee5b9dbceaae41b8890e7c81240f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Date: Thu, 1 Feb 2018 14:27:53 +0100 Subject: [PATCH] memfd: add hugetlbsize argument MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Learn to specificy hugetlb size as qemu_memfd_create() argument. Signed-off-by: Marc-André Lureau Message-Id: <20180201132757.23063-4-marcandre.lureau@redhat.com> Signed-off-by: Paolo Bonzini --- include/qemu/memfd.h | 2 +- util/memfd.c | 22 ++++++++++++++++++---- 2 files changed, 19 insertions(+), 5 deletions(-) diff --git a/include/qemu/memfd.h b/include/qemu/memfd.h index 1d3ecc7458..de10198ed6 100644 --- a/include/qemu/memfd.h +++ b/include/qemu/memfd.h @@ -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); diff --git a/util/memfd.c b/util/memfd.c index 7594af7089..07d579ea7d 100644 --- a/util/memfd.c +++ b/util/memfd.c @@ -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 @@ -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) {