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 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_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 false; 37 } 38 39 backend->aligned = true; 40 name = object_get_canonical_path(OBJECT(backend)); 41 ram_flags = (backend->share ? RAM_SHARED : 0) | RAM_PROTECTED; 42 return memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend), name, 43 backend->size, ram_flags, fd, 0, errp); 44 } 45 46 static void sgx_epc_backend_instance_init(Object *obj) 47 { 48 HostMemoryBackend *m = MEMORY_BACKEND(obj); 49 50 m->share = true; 51 m->merge = false; 52 m->dump = false; 53 } 54 55 static void sgx_epc_backend_class_init(ObjectClass *oc, void *data) 56 { 57 HostMemoryBackendClass *bc = MEMORY_BACKEND_CLASS(oc); 58 59 bc->alloc = sgx_epc_backend_memory_alloc; 60 } 61 62 static const TypeInfo sgx_epc_backed_info = { 63 .name = TYPE_MEMORY_BACKEND_EPC, 64 .parent = TYPE_MEMORY_BACKEND, 65 .instance_init = sgx_epc_backend_instance_init, 66 .class_init = sgx_epc_backend_class_init, 67 .instance_size = sizeof(HostMemoryBackendEpc), 68 }; 69 70 static void register_types(void) 71 { 72 int fd = qemu_open_old("/dev/sgx_vepc", O_RDWR); 73 if (fd >= 0) { 74 close(fd); 75 76 type_register_static(&sgx_epc_backed_info); 77 } 78 } 79 80 type_init(register_types); 81