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 "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
  21static void
  22sgx_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
  48static 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
  57static 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
  64static 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
  72static 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
  82type_init(register_types);
  83