1 /*
2 * QEMU host SGX EPC memory backend
3 *
4 * Copyright (C) 2019 Intel Corporation
5 *
6 * Authors:
7 * Sean Christopherson <sean.j.christopherson@intel.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
10 * See the COPYING file in the top-level directory.
11 */
12
13 #include "qemu/osdep.h"
14 #include <sys/ioctl.h>
15 #include "qom/object_interfaces.h"
16 #include "qapi/error.h"
17 #include "sysemu/hostmem.h"
18 #include "hw/i386/hostmem-epc.h"
19
20 static bool
sgx_epc_backend_memory_alloc(HostMemoryBackend * backend,Error ** errp)21 sgx_epc_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
22 {
23 g_autofree char *name = NULL;
24 uint32_t ram_flags;
25 int fd;
26
27 if (!backend->size) {
28 error_setg(errp, "can't create backend with size 0");
29 return false;
30 }
31
32 fd = qemu_open("/dev/sgx_vepc", O_RDWR, errp);
33 if (fd < 0) {
34 return false;
35 }
36
37 backend->aligned = true;
38 name = object_get_canonical_path(OBJECT(backend));
39 ram_flags = (backend->share ? RAM_SHARED : 0) | RAM_PROTECTED;
40 return memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend), name,
41 backend->size, ram_flags, fd, 0, errp);
42 }
43
sgx_epc_backend_instance_init(Object * obj)44 static void sgx_epc_backend_instance_init(Object *obj)
45 {
46 HostMemoryBackend *m = MEMORY_BACKEND(obj);
47
48 m->share = true;
49 m->merge = false;
50 m->dump = false;
51 }
52
sgx_epc_backend_class_init(ObjectClass * oc,void * data)53 static void sgx_epc_backend_class_init(ObjectClass *oc, void *data)
54 {
55 HostMemoryBackendClass *bc = MEMORY_BACKEND_CLASS(oc);
56
57 bc->alloc = sgx_epc_backend_memory_alloc;
58 }
59
60 static const TypeInfo sgx_epc_backed_info = {
61 .name = TYPE_MEMORY_BACKEND_EPC,
62 .parent = TYPE_MEMORY_BACKEND,
63 .instance_init = sgx_epc_backend_instance_init,
64 .class_init = sgx_epc_backend_class_init,
65 .instance_size = sizeof(HostMemoryBackendEpc),
66 };
67
register_types(void)68 static void register_types(void)
69 {
70 int fd = qemu_open_old("/dev/sgx_vepc", O_RDWR);
71 if (fd >= 0) {
72 close(fd);
73
74 type_register_static(&sgx_epc_backed_info);
75 }
76 }
77
78 type_init(register_types);
79