qemu-e2k/hw/mem/nvdimm.c
Haozhong Zhang cb836434cd nvdimm: add 'unarmed' option
Currently the only vNVDIMM backend can guarantee the guest write
persistence is device DAX on Linux, because no host-side kernel cache
is involved in the guest access to it. The approach to detect whether
the backend is device DAX needs to access sysfs, which may not work
with SELinux.

Instead, we add the 'unarmed' option to device 'nvdimm', so that users
or management utils, which have enough knowledge about the backend,
can control the unarmed flag in guest ACPI NFIT via this option. The
guest Linux NVDIMM driver, for example, will mark the corresponding
vNVDIMM device read-only if the unarmed flag in guest NFIT is set.

The default value of 'unarmed' option is 'off' in order to keep the
backwards compatibility.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Message-Id: <20171211072806.2812-4-haozhong.zhang@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2018-01-19 11:18:51 -02:00

203 lines
6.2 KiB
C

/*
* Non-Volatile Dual In-line Memory Module Virtualization Implementation
*
* Copyright(C) 2015 Intel Corporation.
*
* Author:
* Xiao Guangrong <guangrong.xiao@linux.intel.com>
*
* Currently, it only supports PMEM Virtualization.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qapi/visitor.h"
#include "qapi-visit.h"
#include "hw/mem/nvdimm.h"
static void nvdimm_get_label_size(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
NVDIMMDevice *nvdimm = NVDIMM(obj);
uint64_t value = nvdimm->label_size;
visit_type_size(v, name, &value, errp);
}
static void nvdimm_set_label_size(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
NVDIMMDevice *nvdimm = NVDIMM(obj);
Error *local_err = NULL;
uint64_t value;
if (memory_region_size(&nvdimm->nvdimm_mr)) {
error_setg(&local_err, "cannot change property value");
goto out;
}
visit_type_size(v, name, &value, &local_err);
if (local_err) {
goto out;
}
if (value < MIN_NAMESPACE_LABEL_SIZE) {
error_setg(&local_err, "Property '%s.%s' (0x%" PRIx64 ") is required"
" at least 0x%lx", object_get_typename(obj),
name, value, MIN_NAMESPACE_LABEL_SIZE);
goto out;
}
nvdimm->label_size = value;
out:
error_propagate(errp, local_err);
}
static bool nvdimm_get_unarmed(Object *obj, Error **errp)
{
NVDIMMDevice *nvdimm = NVDIMM(obj);
return nvdimm->unarmed;
}
static void nvdimm_set_unarmed(Object *obj, bool value, Error **errp)
{
NVDIMMDevice *nvdimm = NVDIMM(obj);
Error *local_err = NULL;
if (memory_region_size(&nvdimm->nvdimm_mr)) {
error_setg(&local_err, "cannot change property value");
goto out;
}
nvdimm->unarmed = value;
out:
error_propagate(errp, local_err);
}
static void nvdimm_init(Object *obj)
{
object_property_add(obj, NVDIMM_LABLE_SIZE_PROP, "int",
nvdimm_get_label_size, nvdimm_set_label_size, NULL,
NULL, NULL);
object_property_add_bool(obj, NVDIMM_UNARMED_PROP,
nvdimm_get_unarmed, nvdimm_set_unarmed, NULL);
}
static MemoryRegion *nvdimm_get_memory_region(PCDIMMDevice *dimm, Error **errp)
{
NVDIMMDevice *nvdimm = NVDIMM(dimm);
return &nvdimm->nvdimm_mr;
}
static void nvdimm_realize(PCDIMMDevice *dimm, Error **errp)
{
MemoryRegion *mr = host_memory_backend_get_memory(dimm->hostmem, errp);
NVDIMMDevice *nvdimm = NVDIMM(dimm);
uint64_t align, pmem_size, size = memory_region_size(mr);
align = memory_region_get_alignment(mr);
pmem_size = size - nvdimm->label_size;
nvdimm->label_data = memory_region_get_ram_ptr(mr) + pmem_size;
pmem_size = QEMU_ALIGN_DOWN(pmem_size, align);
if (size <= nvdimm->label_size || !pmem_size) {
HostMemoryBackend *hostmem = dimm->hostmem;
char *path = object_get_canonical_path_component(OBJECT(hostmem));
error_setg(errp, "the size of memdev %s (0x%" PRIx64 ") is too "
"small to contain nvdimm label (0x%" PRIx64 ") and "
"aligned PMEM (0x%" PRIx64 ")",
path, memory_region_size(mr), nvdimm->label_size, align);
g_free(path);
return;
}
memory_region_init_alias(&nvdimm->nvdimm_mr, OBJECT(dimm),
"nvdimm-memory", mr, 0, pmem_size);
nvdimm->nvdimm_mr.align = align;
}
/*
* the caller should check the input parameters before calling
* label read/write functions.
*/
static void nvdimm_validate_rw_label_data(NVDIMMDevice *nvdimm, uint64_t size,
uint64_t offset)
{
assert((nvdimm->label_size >= size + offset) && (offset + size > offset));
}
static void nvdimm_read_label_data(NVDIMMDevice *nvdimm, void *buf,
uint64_t size, uint64_t offset)
{
nvdimm_validate_rw_label_data(nvdimm, size, offset);
memcpy(buf, nvdimm->label_data + offset, size);
}
static void nvdimm_write_label_data(NVDIMMDevice *nvdimm, const void *buf,
uint64_t size, uint64_t offset)
{
MemoryRegion *mr;
PCDIMMDevice *dimm = PC_DIMM(nvdimm);
uint64_t backend_offset;
nvdimm_validate_rw_label_data(nvdimm, size, offset);
memcpy(nvdimm->label_data + offset, buf, size);
mr = host_memory_backend_get_memory(dimm->hostmem, &error_abort);
backend_offset = memory_region_size(mr) - nvdimm->label_size + offset;
memory_region_set_dirty(mr, backend_offset, size);
}
static MemoryRegion *nvdimm_get_vmstate_memory_region(PCDIMMDevice *dimm)
{
return host_memory_backend_get_memory(dimm->hostmem, &error_abort);
}
static void nvdimm_class_init(ObjectClass *oc, void *data)
{
PCDIMMDeviceClass *ddc = PC_DIMM_CLASS(oc);
NVDIMMClass *nvc = NVDIMM_CLASS(oc);
ddc->realize = nvdimm_realize;
ddc->get_memory_region = nvdimm_get_memory_region;
ddc->get_vmstate_memory_region = nvdimm_get_vmstate_memory_region;
nvc->read_label_data = nvdimm_read_label_data;
nvc->write_label_data = nvdimm_write_label_data;
}
static TypeInfo nvdimm_info = {
.name = TYPE_NVDIMM,
.parent = TYPE_PC_DIMM,
.class_size = sizeof(NVDIMMClass),
.class_init = nvdimm_class_init,
.instance_size = sizeof(NVDIMMDevice),
.instance_init = nvdimm_init,
};
static void nvdimm_register_types(void)
{
type_register_static(&nvdimm_info);
}
type_init(nvdimm_register_types)