From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43900) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ejKFD-0004st-Pb for qemu-devel@nongnu.org; Wed, 07 Feb 2018 02:34:18 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ejKFC-0000Zr-Ru for qemu-devel@nongnu.org; Wed, 07 Feb 2018 02:34:15 -0500 Received: from mga09.intel.com ([134.134.136.24]:13680) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ejKFC-0000Td-KJ for qemu-devel@nongnu.org; Wed, 07 Feb 2018 02:34:14 -0500 From: Haozhong Zhang Date: Wed, 7 Feb 2018 15:33:27 +0800 Message-Id: <20180207073331.14158-5-haozhong.zhang@intel.com> In-Reply-To: <20180207073331.14158-1-haozhong.zhang@intel.com> References: <20180207073331.14158-1-haozhong.zhang@intel.com> Subject: [Qemu-devel] [PATCH v2 4/8] mem/nvdimm: ensure write persistence to PMEM in label emulation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Eduardo Habkost , Igor Mammedov , Paolo Bonzini , mst@redhat.com, Xiao Guangrong , Juan Quintela , dgilbert@redhat.com, Stefan Hajnoczi , Dan Williams , Haozhong Zhang 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 --- hw/mem/nvdimm.c | 9 ++++++++- include/qemu/pmem.h | 31 +++++++++++++++++++++++++++++++ 2 files changed, 39 insertions(+), 1 deletion(-) create mode 100644 include/qemu/pmem.h diff --git a/hw/mem/nvdimm.c b/hw/mem/nvdimm.c index 61e677f92f..18861d1a7a 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 "qapi-visit.h" @@ -156,11 +157,17 @@ 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, &error_abort); backend_offset = memory_region_size(mr) - nvdimm->label_size + offset; diff --git a/include/qemu/pmem.h b/include/qemu/pmem.h new file mode 100644 index 0000000000..9017596ff0 --- /dev/null +++ b/include/qemu/pmem.h @@ -0,0 +1,31 @@ +/* + * Stub functions for libpmem. + * + * Copyright (c) 2018 Intel Corporation. + * + * Author: Haozhong Zhang + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_PMEM_H +#define QEMU_PMEM_H + +#ifdef CONFIG_LIBPMEM +#include +#else /* !CONFIG_LIBPMEM */ + +#include + +/* Stubs */ + +static inline void * +pmem_memcpy_persist(void *pmemdest, const void *src, size_t len) +{ + return memcpy(pmemdest, src, len); +} + +#endif /* CONFIG_LIBPMEM */ + +#endif /* !QEMU_PMEM_H */ -- 2.14.1