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 #include <sys/ioctl.h> 13 14 #include "qemu/osdep.h" 15 #include "qemu-common.h" 16 #include "qom/object_interfaces.h" 17 #include "qapi/error.h" 18 #include "sysemu/hostmem.h" 19 #include "hw/i386/hostmem-epc.h" 20 21 static void 22 sgx_epc_backend_memory_alloc(HostMemoryBackend *backend, Error **errp) 23 { 24 uint32_t ram_flags; 25 char *name; 26 int fd; 27 28 if (!backend->size) { 29 error_setg(errp, "can't create backend with size 0"); 30 return; 31 } 32 33 fd = qemu_open_old("/dev/sgx_vepc", O_RDWR); 34 if (fd < 0) { 35 error_setg_errno(errp, errno, 36 "failed to open /dev/sgx_vepc to alloc SGX EPC"); 37 return; 38 } 39 40 name = object_get_canonical_path(OBJECT(backend)); 41 ram_flags = (backend->share ? RAM_SHARED : 0) | RAM_PROTECTED; 42 memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend), 43 name, backend->size, ram_flags, 44 fd, 0, errp); 45 g_free(name); 46 } 47 48 static void sgx_epc_backend_instance_init(Object *obj) 49 { 50 HostMemoryBackend *m = MEMORY_BACKEND(obj); 51 52 m->share = true; 53 m->merge = false; 54 m->dump = false; 55 } 56 57 static void sgx_epc_backend_class_init(ObjectClass *oc, void *data) 58 { 59 HostMemoryBackendClass *bc = MEMORY_BACKEND_CLASS(oc); 60 61 bc->alloc = sgx_epc_backend_memory_alloc; 62 } 63 64 static const TypeInfo sgx_epc_backed_info = { 65 .name = TYPE_MEMORY_BACKEND_EPC, 66 .parent = TYPE_MEMORY_BACKEND, 67 .instance_init = sgx_epc_backend_instance_init, 68 .class_init = sgx_epc_backend_class_init, 69 .instance_size = sizeof(HostMemoryBackendEpc), 70 }; 71 72 static void register_types(void) 73 { 74 int fd = qemu_open_old("/dev/sgx_vepc", O_RDWR); 75 if (fd >= 0) { 76 close(fd); 77 78 type_register_static(&sgx_epc_backed_info); 79 } 80 } 81 82 type_init(register_types); 83