LXR qemu/backends/hostmem-epc.c

   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 "qom/object_interfaces.h"
  16#include "qapi/error.h"
  17#include "sysemu/hostmem.h"
  18#include "hw/i386/hostmem-epc.h"
  19
  20static void
  21sgx_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
  47static 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
  56static 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
  63static 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
  71static 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
  81type_init(register_types);
  82