include/sysemu/hostmem.h

   1 /*
   2  * QEMU Host Memory Backend
   3  *
   4  * Copyright (C) 2013-2014 Red Hat Inc
   5  *
   6  * Authors:
   7  *   Igor Mammedov <imammedo@redhat.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 #ifndef SYSEMU_HOSTMEM_H
  14 #define SYSEMU_HOSTMEM_H
  15
  16 #include "sysemu/numa.h"
  17 #include "qapi/qapi-types-machine.h"
  18 #include "qom/object.h"
  19 #include "exec/memory.h"
  20 #include "qemu/bitmap.h"
  21 #include "qemu/thread-context.h"
  22
  23 #define TYPE_MEMORY_BACKEND "memory-backend"
  24 OBJECT_DECLARE_TYPE(HostMemoryBackend, HostMemoryBackendClass,
  25                     MEMORY_BACKEND)
  26
  27 /* hostmem-ram.c */
  28 /**
  29  * @TYPE_MEMORY_BACKEND_RAM:
  30  * name of backend that uses mmap on the anonymous RAM
  31  */
  32
  33 #define TYPE_MEMORY_BACKEND_RAM "memory-backend-ram"
  34
  35 /* hostmem-file.c */
  36 /**
  37  * @TYPE_MEMORY_BACKEND_FILE:
  38  * name of backend that uses mmap on a file descriptor
  39  */
  40 #define TYPE_MEMORY_BACKEND_FILE "memory-backend-file"
  41
  42
  43 /**
  44  * HostMemoryBackendClass:
  45  * @parent_class: opaque parent class container
  46  */
  47 struct HostMemoryBackendClass {
  48     ObjectClass parent_class;
  49
  50     /**
  51      * alloc: Allocate memory from backend.
  52      *
  53      * @backend: the #HostMemoryBackend.
  54      * @errp: pointer to Error*, to store an error if it happens.
  55      *
  56      * Return: true on success, else false setting @errp with error.
  57      */
  58     bool (*alloc)(HostMemoryBackend *backend, Error **errp);
  59 };
  60
  61 /**
  62  * @HostMemoryBackend
  63  *
  64  * @parent: opaque parent object container
  65  * @size: amount of memory backend provides
  66  * @mr: MemoryRegion representing host memory belonging to backend
  67  * @prealloc_threads: number of threads to be used for preallocatining RAM
  68  */
  69 struct HostMemoryBackend {
  70     /* private */
  71     Object parent;
  72
  73     /* protected */
  74     uint64_t size;
  75     bool merge, dump, use_canonical_path;
  76     bool prealloc, is_mapped, share, reserve;
  77     bool guest_memfd, aligned;
  78     uint32_t prealloc_threads;
  79     ThreadContext *prealloc_context;
  80     DECLARE_BITMAP(host_nodes, MAX_NODES + 1);
  81     HostMemPolicy policy;
  82
  83     MemoryRegion mr;
  84 };
  85
  86 bool host_memory_backend_mr_inited(HostMemoryBackend *backend);
  87 MemoryRegion *host_memory_backend_get_memory(HostMemoryBackend *backend);
  88
  89 void host_memory_backend_set_mapped(HostMemoryBackend *backend, bool mapped);
  90 bool host_memory_backend_is_mapped(HostMemoryBackend *backend);
  91 size_t host_memory_backend_pagesize(HostMemoryBackend *memdev);
  92 char *host_memory_backend_get_name(HostMemoryBackend *backend);
  93
  94 #endif