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-rw-r--r--qemu/backends/hostmem-file.c134
1 files changed, 134 insertions, 0 deletions
diff --git a/qemu/backends/hostmem-file.c b/qemu/backends/hostmem-file.c
new file mode 100644
index 000000000..4b5536101
--- /dev/null
+++ b/qemu/backends/hostmem-file.c
@@ -0,0 +1,134 @@
+/*
+ * 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-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)) {
+ backend->force_prealloc = mem_prealloc;
+ memory_region_init_ram_from_file(&backend->mr, OBJECT(backend),
+ object_get_canonical_path(OBJECT(backend)),
+ backend->size, fb->share,
+ fb->mem_path, errp);
+ }
+#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;
+ }
+ if (fb->mem_path) {
+ 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 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_size = sizeof(HostMemoryBackendFile),
+};
+
+static void register_types(void)
+{
+ type_register_static(&file_backend_info);
+}
+
+type_init(register_types);