From patchwork Fri Jun 9 20:24:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 9779177 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9764B60352 for ; Fri, 9 Jun 2017 20:30:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8A348286F9 for ; Fri, 9 Jun 2017 20:30:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7EF2728704; Fri, 9 Jun 2017 20:30:37 +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=-1.9 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 33338286F9 for ; Fri, 9 Jun 2017 20:30:37 +0000 (UTC) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 94F6821967BED; Fri, 9 Jun 2017 13:29:26 -0700 (PDT) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id A4E2421A143F1 for ; Fri, 9 Jun 2017 13:29:25 -0700 (PDT) Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 09 Jun 2017 13:30:36 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.39,319,1493708400"; d="scan'208";a="112557309" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.125]) by fmsmga005.fm.intel.com with ESMTP; 09 Jun 2017 13:30:34 -0700 Subject: [PATCH v3 04/14] dax, pmem: introduce an optional 'flush' dax_operation From: Dan Williams To: linux-nvdimm@lists.01.org Date: Fri, 09 Jun 2017 13:24:07 -0700 Message-ID: <149703984722.20620.1577767383686219477.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <149703982465.20620.14881139332926778446.stgit@dwillia2-desk3.amr.corp.intel.com> References: <149703982465.20620.14881139332926778446.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.17.1-9-g687f MIME-Version: 1.0 X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Matthew Wilcox , x86@kernel.org, linux-kernel@vger.kernel.org, dm-devel@redhat.com, viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, hch@lst.de Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Virus-Scanned: ClamAV using ClamSMTP Filesystem-DAX flushes caches whenever it writes to the address returned through dax_direct_access() and when writing back dirty radix entries. That flushing is only required in the pmem case, so add a dax operation to allow pmem to take this extra action, but skip it for other dax capable devices that do not provide a flush routine. An example for this differentiation might be a volatile ram disk where there is no expectation of persistence. In fact the pmem driver itself might front such an address range specified by the NFIT. So, this "no flush" property might be something passed down by the bus / libnvdimm. Cc: Christoph Hellwig Cc: Matthew Wilcox Cc: Ross Zwisler Signed-off-by: Dan Williams Reviewed-by: Jan Kara --- drivers/nvdimm/pmem.c | 7 +++++++ include/linux/dax.h | 2 ++ 2 files changed, 9 insertions(+) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 2f3aefe565c6..823b07774244 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -242,9 +242,16 @@ static size_t pmem_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, return copy_from_iter_flushcache(addr, bytes, i); } +static void pmem_dax_flush(struct dax_device *dax_dev, pgoff_t pgoff, + void *addr, size_t size) +{ + wb_cache_pmem(addr, size); +} + static const struct dax_operations pmem_dax_ops = { .direct_access = pmem_dax_direct_access, .copy_from_iter = pmem_copy_from_iter, + .flush = pmem_dax_flush, }; static void pmem_release_queue(void *q) diff --git a/include/linux/dax.h b/include/linux/dax.h index 28e398f8c59e..407dd3ff6e54 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -19,6 +19,8 @@ struct dax_operations { /* copy_from_iter: dax-driver override for default copy_from_iter */ size_t (*copy_from_iter)(struct dax_device *, pgoff_t, void *, size_t, struct iov_iter *); + /* flush: optional driver-specific cache management after writes */ + void (*flush)(struct dax_device *, pgoff_t, void *, size_t); }; #if IS_ENABLED(CONFIG_DAX)