hostmem-epc.c
/*
* QEMU host SGX EPC memory backend
*
* Copyright (C) 2019 Intel Corporation
*
* Authors:
* Sean Christopherson <sean.j.christopherson@intel.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include <sys/ioctl.h>
#include "qemu/osdep.h"
#include "qom/object_interfaces.h"
#include "qapi/error.h"
#include "sysemu/hostmem.h"
#include "hw/i386/hostmem-epc.h"
static void
sgx_epc_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
{
uint32_t ram_flags;
char *name;
int fd;
if (!backend->size) {
error_setg(errp, "can't create backend with size 0");
return;
}
fd = qemu_open_old("/dev/sgx_vepc", O_RDWR);
if (fd < 0) {
error_setg_errno(errp, errno,
"failed to open /dev/sgx_vepc to alloc SGX EPC");
return;
}
name = object_get_canonical_path(OBJECT(backend));
ram_flags = (backend->share ? RAM_SHARED : 0) | RAM_PROTECTED;
memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend),
name, backend->size, ram_flags,
fd, 0, errp);
g_free(name);
}
static void sgx_epc_backend_instance_init(Object *obj)
{
HostMemoryBackend *m = MEMORY_BACKEND(obj);
m->share = true;
m->merge = false;
m->dump = false;
}
static void sgx_epc_backend_class_init(ObjectClass *oc, void *data)
{
HostMemoryBackendClass *bc = MEMORY_BACKEND_CLASS(oc);
bc->alloc = sgx_epc_backend_memory_alloc;
}
static const TypeInfo sgx_epc_backed_info = {
.name = TYPE_MEMORY_BACKEND_EPC,
.parent = TYPE_MEMORY_BACKEND,
.instance_init = sgx_epc_backend_instance_init,
.class_init = sgx_epc_backend_class_init,
.instance_size = sizeof(HostMemoryBackendEpc),
};
static void register_types(void)
{
int fd = qemu_open_old("/dev/sgx_vepc", O_RDWR);
if (fd >= 0) {
close(fd);
type_register_static(&sgx_epc_backed_info);
}
}
type_init(register_types);