mem/nvdimm: ensure write persistence to PMEM in label emulation

Guest writes to vNVDIMM labels are intercepted and performed on the
backend by QEMU. When the backend is a real persistent memort, QEMU
needs to take proper operations to ensure its write persistence on the
persistent memory. Otherwise, a host power failure may result in the
loss of guest label configurations.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Junyan He 2018-07-18 15:48:01 +08:00 committed by Michael S. Tsirkin
parent a4de8552b2
commit faf8a13d80
2 changed files with 38 additions and 1 deletions

View file

@ -23,6 +23,7 @@
*/
#include "qemu/osdep.h"
#include "qemu/pmem.h"
#include "qapi/error.h"
#include "qapi/visitor.h"
#include "hw/mem/nvdimm.h"
@ -164,11 +165,17 @@ static void nvdimm_write_label_data(NVDIMMDevice *nvdimm, const void *buf,
{
MemoryRegion *mr;
PCDIMMDevice *dimm = PC_DIMM(nvdimm);
bool is_pmem = object_property_get_bool(OBJECT(dimm->hostmem),
"pmem", NULL);
uint64_t backend_offset;
nvdimm_validate_rw_label_data(nvdimm, size, offset);
memcpy(nvdimm->label_data + offset, buf, size);
if (!is_pmem) {
memcpy(nvdimm->label_data + offset, buf, size);
} else {
pmem_memcpy_persist(nvdimm->label_data + offset, buf, size);
}
mr = host_memory_backend_get_memory(dimm->hostmem);
backend_offset = memory_region_size(mr) - nvdimm->label_size + offset;