/* * QEMU Host Memory Backend for hugetlbfs * * Copyright (C) 2013-2014 Red Hat Inc * * Authors: * Paolo Bonzini <pbonzini@redhat.com> * * This work is licensed under the terms of the GNU GPL, version 2 or later. * See the COPYING file in the top-level directory. */ #include "qemu/osdep.h" #include "qapi/error.h" #include "qemu-common.h" #include "sysemu/hostmem.h" #include "sysemu/sysemu.h" #include "qom/object_interfaces.h" /* hostmem-file.c */ /** * @TYPE_MEMORY_BACKEND_FILE: * name of backend that uses mmap on a file descriptor */ #define TYPE_MEMORY_BACKEND_FILE "memory-backend-file" #define MEMORY_BACKEND_FILE(obj) \ OBJECT_CHECK(HostMemoryBackendFile, (obj), TYPE_MEMORY_BACKEND_FILE) typedef struct HostMemoryBackendFile HostMemoryBackendFile; struct HostMemoryBackendFile { HostMemoryBackend parent_obj; bool share; char *mem_path; }; static void file_backend_memory_alloc(HostMemoryBackend *backend, Error **errp) { HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(backend); if (!backend->size) { error_setg(errp, "can't create backend with size 0"); return; } if (!fb->mem_path) { error_setg(errp, "mem-path property not set"); return; } #ifndef CONFIG_LINUX error_setg(errp, "-mem-path not supported on this host"); #else if (!memory_region_size(&backend->mr)) { gchar *path; backend->force_prealloc = mem_prealloc; path = object_get_canonical_path(OBJECT(backend)); memory_region_init_ram_from_file(&backend->mr, OBJECT(backend), path, backend->size, fb->share, fb->mem_path, errp); g_free(path); } #endif } static void file_backend_class_init(ObjectClass *oc, void *data) { HostMemoryBackendClass *bc = MEMORY_BACKEND_CLASS(oc); bc->alloc = file_backend_memory_alloc; } static char *get_mem_path(Object *o, Error **errp) { HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o); return g_strdup(fb->mem_path); } static void set_mem_path(Object *o, const char *str, Error **errp) { HostMemoryBackend *backend = MEMORY_BACKEND(o); HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o); if (memory_region_size(&backend->mr)) { error_setg(errp, "cannot change property value"); return; } g_free(fb->mem_path); fb->mem_path = g_strdup(str); } static bool file_memory_backend_get_share(Object *o, Error **errp) { HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o); return fb->share; } static void file_memory_backend_set_share(Object *o, bool value, Error **errp) { HostMemoryBackend *backend = MEMORY_BACKEND(o); HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o); if (memory_region_size(&backend->mr)) { error_setg(errp, "cannot change property value"); return; } fb->share = value; } static void file_backend_instance_init(Object *o) { object_property_add_bool(o, "share", file_memory_backend_get_share, file_memory_backend_set_share, NULL); object_property_add_str(o, "mem-path", get_mem_path, set_mem_path, NULL); } static void file_backend_instance_finalize(Object *o) { HostMemoryBackendFile *fb = MEMORY_BACKEND_FILE(o); g_free(fb->mem_path); } static const TypeInfo file_backend_info = { .name = TYPE_MEMORY_BACKEND_FILE, .parent = TYPE_MEMORY_BACKEND, .class_init = file_backend_class_init, .instance_init = file_backend_instance_init, .instance_finalize = file_backend_instance_finalize, .instance_size = sizeof(HostMemoryBackendFile), }; static void register_types(void) { type_register_static(&file_backend_info); } type_init(register_types);