From patchwork Fri Feb 8 10:10:23 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zhang, Yi" X-Patchwork-Id: 10802327 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AF9B113A4 for ; Fri, 8 Feb 2019 01:40:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 991AF2E47C for ; Fri, 8 Feb 2019 01:40:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8CFA82E4A7; Fri, 8 Feb 2019 01:40:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=2.0 tests=BAYES_00,DATE_IN_FUTURE_06_12, MAILING_LIST_MULTI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D581E2E47C for ; Fri, 8 Feb 2019 01:40:52 +0000 (UTC) Received: from localhost ([127.0.0.1]:49494 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1grv9w-0008UK-5f for patchwork-qemu-devel@patchwork.kernel.org; Thu, 07 Feb 2019 20:40:52 -0500 Received: from eggs.gnu.org ([209.51.188.92]:60571) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1grv8w-0008U2-9N for qemu-devel@nongnu.org; Thu, 07 Feb 2019 20:39:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1grv8u-0004e6-M2 for qemu-devel@nongnu.org; Thu, 07 Feb 2019 20:39:50 -0500 Received: from mga04.intel.com ([192.55.52.120]:48408) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1grv8u-0004bz-C0 for qemu-devel@nongnu.org; Thu, 07 Feb 2019 20:39:48 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Feb 2019 17:39:38 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,346,1544515200"; d="scan'208";a="136794360" Received: from dazhang1-ssd.sh.intel.com (HELO localhost) ([10.239.48.91]) by orsmga001.jf.intel.com with ESMTP; 07 Feb 2019 17:39:35 -0800 From: "Zhang, Yi" To: xiaoguangrong.eric@gmail.com, stefanha@redhat.com, pbonzini@redhat.com, pagupta@redhat.com, yu.c.zhang@linux.intel.com, richardw.yang@linux.intel.com, mst@redhat.com, ehabkost@redhat.com Date: Fri, 8 Feb 2019 18:10:23 +0800 Message-Id: X-Mailer: git-send-email 2.7.4 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 192.55.52.120 Subject: [Qemu-devel] [PATCH V13 0/5] support MAP_SYNC for memory-backend-file X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: imammedo@redhat.com, dan.j.williams@intel.com, qemu-devel@nongnu.org, "Zhang, Yi" Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP Linux 4.15 introduces a new mmap flag MAP_SYNC, which can be used to guarantee the write persistence to mmap'ed files supporting DAX (e.g., files on ext4/xfs file system mounted with '-o dax'). A description of MAP_SYNC and MAP_SHARED_VALIDATE can be found at https://patchwork.kernel.org/patch/10028151/ In order to make sure that the file metadata is in sync after a fault while we are writing a shared DAX supporting backend files, this patch-set enables QEMU to use MAP_SYNC flag for memory-backend-dax-file. As the DAX vs DMA truncated issue was solved, we refined the code and send out this feature for the v5 version. We will pass MAP_SYNC to mmap(2); if MAP_SYNC is supported and 'share=on' & 'pmem=on'. Or QEMU will not pass this flag to mmap(2) Test with below cases: 1. pmem=on is set, shared=on is set, MAP_SYNC supported: a: backend is a dax supporting file. 1) start VM1 with options: -object memory-backend-file,id=nv_be4,share,mem-path=${DAX_FILE_1},size=${DAX_FILE_SIZE_1},align=128M,pmem=on,share=on -device nvdimm,id=nv4,memdev=nv_be4,label-size=2M. 2) start VM2 with options: -object memory-backend-file,id=nv_be4,share,mem-path=${DAX_FILE_2,size=${DAX_FILE_SIZE_2},align=128M,pmem=on,share=on -device nvdimm,id=nv4,memdev=nv_be4,label-size=2M. 3) live migrate from VM1 to VM2. 4) Suddly let Host crash or power failure. 5) check DAX_FILE_1 and DAX_FILE_2, no corrupt. b: backend is a regular file. 1) start with options -object memory-backend-file,id=nv_be4,share,mem-path=${REG_FILE},size=${REG_FILE_SIZE},align=128M,pmem=on,share=on -device nvdimm,id=nv4,memdev=nv_be4,label-size=2M. will warning "failed to validate with mapping flags: Operation not supported" FILE_1 and FILE_2 random corrupt. 2. Other cases: FILE_1 and FILE_2 random corrupt. Changes in V13: * 4/5 Micheal: move the inlcude to mmap_alloc.c. * 4/5 Micheal: refine the warning message. * 5/5 Micheal: refine the Documentations. Changes in V12: * 2/5: Micheal: Update update-linux-headers.sh * 3/5: Micheal: Use script update add linux/mman.h * 4/5: Pankaj,Micheal: 1) fallback to mmap without MAP_SYNC & MAP_SHARED_VALIDATE if sync not supported or failed 2) Replace the include with 3/5 added linux/mman.h * 5/5: Micheal: Refine the Documentations. Changes in V11: * 1/3: Micheal: Change to just add a bool is_pmem in qemu_ram_mmap. * 2/3: Micheal: Fix the compatibility for old kernel. * 2/3&3/3: Micheal&Eduardo :Update the behavior below: Waning at no-dax and continue without MAP_SYNC. Test if fails again for compatibility, then remove the MAP_VALIDATE and silently proceed. Changes in V10: * 4/4: refine the document. * 3/4: Reviewed-by: Stefano Garzarella * 2/4: refine the commit message, Added MAP_SHARED_VALIDATE. * 2/4: Fix the wrong include header Changes in V9: * 1/6: Reviewed-by: Eduardo Habkost * 2/6: New Added: Micheal: use sparse feature define RAM_FLAG. since I don't have much knowledge about the sparse feature, @Micheal Could you add some documentation/commit message on this patch? Thank you very much. * 3/6: from 2/5: Eduardo: updated the commit message. * 4/6: from 3/5: Micheal: don't ignore MAP_SYNC failures silently. * 5/6: from 4/5: Eduardo: updated the commit message. * 6/6: from 5/5: Micheal: Drop the sync option, document the MAP_SYNC. Changes in v8: * Micheal: 3/5, remove the duplicated define in the os_dep.h * Micheal: 2/5, make type define safety. * Micheal: 2/5, fixed the incorrect define MAP_SHARE on qemu_anon_ram_alloc. * 4/6 removed, we remove the on/off/auto define of sync, as by now, MAP_SYNC only worked with pmem=on. * @Micheal, I still reuse the RAM_SYNC flag, it is much straightforward to parse all the flags in one parameter. Changes in v7: * Micheal: [3,4,6]/6 limited the "sync" flag only on a nvdimm backend.(pmem=on) Changes in v6: * Pankaj: 3/7 are squashed with 2/7 * Pankaj: 7/7 update comments to "consistent filesystem metadata". * Pankaj, Igor: 1/7 Added Reviewed-by in patch-1/7 * Stefan, 4/7 move the include header from "/linux/mman.h" to "osdep.h" * Stefan, 5/7 Add missing "munmap" * Stefan, 2/7 refine the shared/flag. Changes in v5: * Add patch 1 to fix a memory leak issue. * Refine the patch 4-6 * Remove the patch 3 as we already change the parameter from "shared" to "flags" Changes in v4: * Add patch 1-3 to switch some functions to a single 'flags' parameters. (Michael S. Tsirkin) * v3 patch 1-3 become v4 patch 4-6. * Patch 4: move definitions of MAP_SYNC and MAP_SHARED_VALIDATE to a new header file under include/standard-headers/linux/. (Michael S. Tsirkin) * Patch 6: refine the description of the 'sync' option. (Michael S. Tsirkin) Changes in v3: * Patch 1: add MAP_SHARED_VALIDATE in both sync=on and sync=auto cases, and add back the retry mechanism. MAP_SYNC will be ignored by Linux kernel 4.15 if MAP_SHARED_VALIDATE is missed. * Patch 1: define MAP_SYNC and MAP_SHARED_VALIDATE as 0 on non-Linux platforms in order to make qemu_ram_mmap() compile on those platforms. * Patch 2&3: include more information in error messages of memory-backend in hope to help user to identify the error. (Dr. David Alan Gilbert) * Patch 3: fix typo in the commit message. (Dr. David Alan Gilbert) Changes in v2: * Add 'sync' option to control the use of MAP_SYNC. (Eduardo Habkost) * Remove the unnecessary set of MAP_SHARED_VALIDATE in some cases and the retry mechanism in qemu_ram_mmap(). (Michael S. Tsirkin) * Move OS dependent definitions of MAP_SYNC and MAP_SHARED_VALIDATE to osdep.h. (Michael S. Tsirkin) Zhang Yi (5): util/mmap-alloc: Add a 'is_pmem' parameter to qemu_ram_mmap scripts/update-linux-headers: add linux/mman.h linux-headers: add linux/mman.h. util/mmap-alloc: support MAP_SYNC in qemu_ram_mmap() docs: Added MAP_SYNC documentation Zhang Yi (5): util/mmap-alloc: Add a 'is_pmem' parameter to qemu_ram_mmap scripts/update-linux-headers: add linux/mman.h linux-headers: add linux/mman.h. util/mmap-alloc: support MAP_SYNC in qemu_ram_mmap() docs: Added MAP_SYNC documentation docs/nvdimm.txt | 25 ++++++- exec.c | 2 +- include/qemu/mmap-alloc.h | 21 +++++- linux-headers/asm-arm/mman.h | 4 ++ linux-headers/asm-arm64/mman.h | 1 + linux-headers/asm-generic/hugetlb_encode.h | 36 ++++++++++ linux-headers/asm-generic/mman-common.h | 77 ++++++++++++++++++++ linux-headers/asm-generic/mman.h | 24 +++++++ linux-headers/asm-mips/mman.h | 108 +++++++++++++++++++++++++++++ linux-headers/asm-powerpc/mman.h | 39 +++++++++++ linux-headers/asm-s390/mman.h | 1 + linux-headers/asm-x86/mman.h | 31 +++++++++ linux-headers/linux/mman.h | 38 ++++++++++ qemu-options.hx | 5 ++ scripts/update-linux-headers.sh | 6 +- util/mmap-alloc.c | 51 +++++++++++++- util/oslib-posix.c | 2 +- 17 files changed, 460 insertions(+), 11 deletions(-) create mode 100644 linux-headers/asm-arm/mman.h create mode 100644 linux-headers/asm-arm64/mman.h create mode 100644 linux-headers/asm-generic/hugetlb_encode.h create mode 100644 linux-headers/asm-generic/mman-common.h create mode 100644 linux-headers/asm-generic/mman.h create mode 100644 linux-headers/asm-mips/mman.h create mode 100644 linux-headers/asm-powerpc/mman.h create mode 100644 linux-headers/asm-s390/mman.h create mode 100644 linux-headers/asm-x86/mman.h create mode 100644 linux-headers/linux/mman.h Reviewed-by: Michael S. Tsirkin Reviewed-by: Pankaj Gupta