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