hw/remote/memory.c

   1 /*
   2  * Memory manager for remote device
   3  *
   4  * Copyright © 2018, 2021 Oracle and/or its affiliates.
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
   7  * See the COPYING file in the top-level directory.
   8  *
   9  */
  10
  11 #include "qemu/osdep.h"
  12
  13 #include "hw/remote/memory.h"
  14 #include "exec/ram_addr.h"
  15 #include "qapi/error.h"
  16
  17 static void remote_sysmem_reset(void)
  18 {
  19     MemoryRegion *sysmem, *subregion, *next;
  20
  21     sysmem = get_system_memory();
  22
  23     QTAILQ_FOREACH_SAFE(subregion, &sysmem->subregions, subregions_link, next) {
  24         if (subregion->ram) {
  25             memory_region_del_subregion(sysmem, subregion);
  26             object_unparent(OBJECT(subregion));
  27         }
  28     }
  29 }
  30
  31 void remote_sysmem_reconfig(MPQemuMsg *msg, Error **errp)
  32 {
  33     ERRP_GUARD();
  34     SyncSysmemMsg *sysmem_info = &msg->data.sync_sysmem;
  35     MemoryRegion *sysmem, *subregion;
  36     static unsigned int suffix;
  37     int region;
  38
  39     sysmem = get_system_memory();
  40
  41     remote_sysmem_reset();
  42
  43     for (region = 0; region < msg->num_fds; region++, suffix++) {
  44         g_autofree char *name = g_strdup_printf("remote-mem-%u", suffix);
  45         subregion = g_new(MemoryRegion, 1);
  46         memory_region_init_ram_from_fd(subregion, NULL,
  47                                        name, sysmem_info->sizes[region],
  48                                        RAM_SHARED, msg->fds[region],
  49                                        sysmem_info->offsets[region],
  50                                        errp);
  51
  52         if (*errp) {
  53             g_free(subregion);
  54             remote_sysmem_reset();
  55             return;
  56         }
  57
  58         memory_region_add_subregion(sysmem, sysmem_info->gpas[region],
  59                                     subregion);
  60
  61     }
  62 }