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-rw-r--r--qemu/util/memfd.c162
1 files changed, 0 insertions, 162 deletions
diff --git a/qemu/util/memfd.c b/qemu/util/memfd.c
deleted file mode 100644
index 7c406914c..000000000
--- a/qemu/util/memfd.c
+++ /dev/null
@@ -1,162 +0,0 @@
-/*
- * memfd.c
- *
- * Copyright (c) 2015 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.
- */
-
-#include "qemu/osdep.h"
-
-#include <glib.h>
-#include <glib/gprintf.h>
-
-#include <sys/mman.h>
-
-#include "qemu/memfd.h"
-
-#ifdef CONFIG_MEMFD
-#include <sys/memfd.h>
-#elif defined CONFIG_LINUX
-#include <sys/syscall.h>
-#include <asm/unistd.h>
-
-static int memfd_create(const char *name, unsigned int flags)
-{
-#ifdef __NR_memfd_create
- return syscall(__NR_memfd_create, name, flags);
-#else
- return -1;
-#endif
-}
-#endif
-
-#ifndef MFD_CLOEXEC
-#define MFD_CLOEXEC 0x0001U
-#endif
-
-#ifndef MFD_ALLOW_SEALING
-#define MFD_ALLOW_SEALING 0x0002U
-#endif
-
-/*
- * This is a best-effort helper for shared memory allocation, with
- * optional sealing. The helper will do his best to allocate using
- * memfd with sealing, but may fallback on other methods without
- * sealing.
- */
-void *qemu_memfd_alloc(const char *name, size_t size, unsigned int seals,
- int *fd)
-{
- void *ptr;
- int mfd = -1;
-
- *fd = -1;
-
-#ifdef CONFIG_LINUX
- if (seals) {
- mfd = memfd_create(name, MFD_ALLOW_SEALING | MFD_CLOEXEC);
- }
-
- if (mfd == -1) {
- /* some systems have memfd without sealing */
- mfd = memfd_create(name, MFD_CLOEXEC);
- seals = 0;
- }
-#endif
-
- if (mfd != -1) {
- if (ftruncate(mfd, size) == -1) {
- perror("ftruncate");
- close(mfd);
- return NULL;
- }
-
- if (seals && fcntl(mfd, F_ADD_SEALS, seals) == -1) {
- perror("fcntl");
- close(mfd);
- return NULL;
- }
- } else {
- const char *tmpdir = g_get_tmp_dir();
- gchar *fname;
-
- fname = g_strdup_printf("%s/memfd-XXXXXX", tmpdir);
- mfd = mkstemp(fname);
- unlink(fname);
- g_free(fname);
-
- if (mfd == -1) {
- perror("mkstemp");
- return NULL;
- }
-
- if (ftruncate(mfd, size) == -1) {
- perror("ftruncate");
- close(mfd);
- return NULL;
- }
- }
-
- ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, mfd, 0);
- if (ptr == MAP_FAILED) {
- perror("mmap");
- close(mfd);
- return NULL;
- }
-
- *fd = mfd;
- return ptr;
-}
-
-void qemu_memfd_free(void *ptr, size_t size, int fd)
-{
- if (ptr) {
- munmap(ptr, size);
- }
-
- if (fd != -1) {
- close(fd);
- }
-}
-
-enum {
- MEMFD_KO,
- MEMFD_OK,
- MEMFD_TODO
-};
-
-bool qemu_memfd_check(void)
-{
- static int memfd_check = MEMFD_TODO;
-
- if (memfd_check == MEMFD_TODO) {
- int fd;
- void *ptr;
-
- ptr = qemu_memfd_alloc("test", 4096, 0, &fd);
- memfd_check = ptr ? MEMFD_OK : MEMFD_KO;
- qemu_memfd_free(ptr, 4096, fd);
- }
-
- return memfd_check == MEMFD_OK;
-}