qemu/backends/hostmem-ram.c
Marcel Apfelbaum 06329ccecf mem: add share parameter to memory-backend-ram
Currently only file backed memory backend can
be created with a "share" flag in order to allow
sharing guest RAM with other processes in the host.

Add the "share" flag also to RAM Memory Backend
in order to allow remapping parts of the guest RAM
to different host virtual addresses. This is needed
by the RDMA devices in order to remap non-contiguous
QEMU virtual addresses to a contiguous virtual address range.

Moved the "share" flag to the Host Memory base class,
modified phys_mem_alloc to include the new parameter
and a new interface memory_region_init_ram_shared_nomigrate.

There are no functional changes if the new flag is not used.

Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Marcel Apfelbaum <marcel@redhat.com>
2018-02-19 13:03:24 +02:00

56 lines
1.3 KiB
C

/*
* QEMU Host Memory Backend
*
* Copyright (C) 2013-2014 Red Hat Inc
*
* Authors:
* Igor Mammedov <imammedo@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 "sysemu/hostmem.h"
#include "qapi/error.h"
#include "qom/object_interfaces.h"
#define TYPE_MEMORY_BACKEND_RAM "memory-backend-ram"
static void
ram_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
{
char *path;
if (!backend->size) {
error_setg(errp, "can't create backend with size 0");
return;
}
path = object_get_canonical_path_component(OBJECT(backend));
memory_region_init_ram_shared_nomigrate(&backend->mr, OBJECT(backend), path,
backend->size, backend->share, errp);
g_free(path);
}
static void
ram_backend_class_init(ObjectClass *oc, void *data)
{
HostMemoryBackendClass *bc = MEMORY_BACKEND_CLASS(oc);
bc->alloc = ram_backend_memory_alloc;
}
static const TypeInfo ram_backend_info = {
.name = TYPE_MEMORY_BACKEND_RAM,
.parent = TYPE_MEMORY_BACKEND,
.class_init = ram_backend_class_init,
};
static void register_types(void)
{
type_register_static(&ram_backend_info);
}
type_init(register_types);