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 void 21 sgx_epc_backend_memory_alloc(HostMemoryBackend *backend, Error **errp) 22 { 23 uint32_t ram_flags; 24 char *name; 25 int fd; 26 27 if (!backend->size) { 28 error_setg(errp, "can't create backend with size 0"); 29 return; 30 } 31 32 fd = qemu_open_old("/dev/sgx_vepc", O_RDWR); 33 if (fd < 0) { 34 error_setg_errno(errp, errno, 35 "failed to open /dev/sgx_vepc to alloc SGX EPC"); 36 return; 37 } 38 39 name = object_get_canonical_path(OBJECT(backend)); 40 ram_flags = (backend->share ? RAM_SHARED : 0) | RAM_PROTECTED; 41 memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend), 42 name, backend->size, ram_flags, 43 fd, 0, errp); 44 g_free(name); 45 } 46 47 static void sgx_epc_backend_instance_init(Object *obj) 48 { 49 HostMemoryBackend *m = MEMORY_BACKEND(obj); 50 51 m->share = true; 52 m->merge = false; 53 m->dump = false; 54 } 55 56 static void sgx_epc_backend_class_init(ObjectClass *oc, void *data) 57 { 58 HostMemoryBackendClass *bc = MEMORY_BACKEND_CLASS(oc); 59 60 bc->alloc = sgx_epc_backend_memory_alloc; 61 } 62 63 static const TypeInfo sgx_epc_backed_info = { 64 .name = TYPE_MEMORY_BACKEND_EPC, 65 .parent = TYPE_MEMORY_BACKEND, 66 .instance_init = sgx_epc_backend_instance_init, 67 .class_init = sgx_epc_backend_class_init, 68 .instance_size = sizeof(HostMemoryBackendEpc), 69 }; 70 71 static void register_types(void) 72 { 73 int fd = qemu_open_old("/dev/sgx_vepc", O_RDWR); 74 if (fd >= 0) { 75 close(fd); 76 77 type_register_static(&sgx_epc_backed_info); 78 } 79 } 80 81 type_init(register_types); 82