From faf8a13d80de98b43342a7ec9878b4fd76b18327 Mon Sep 17 00:00:00 2001 From: Junyan He Date: Wed, 18 Jul 2018 15:48:01 +0800 Subject: 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 Reviewed-by: Stefan Hajnoczi Reviewed-by: Igor Mammedov Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin Reviewed-by: Richard Henderson --- hw/mem/nvdimm.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'hw') diff --git a/hw/mem/nvdimm.c b/hw/mem/nvdimm.c index 021d1c3..1c6674c 100644 --- a/hw/mem/nvdimm.c +++ b/hw/mem/nvdimm.c @@ -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; -- cgit v1.1