From patchwork Fri Mar 1 04:24:48 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 10834421 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 46A0613B5 for ; Fri, 1 Mar 2019 04:24:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 309D52EF23 for ; Fri, 1 Mar 2019 04:24:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 250922EF2A; Fri, 1 Mar 2019 04:24:57 +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=-2.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=unavailable 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 D34182EF23 for ; Fri, 1 Mar 2019 04:24:56 +0000 (UTC) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 79A72211CFFFE; Thu, 28 Feb 2019 20:24:56 -0800 (PST) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received-SPF: None (no SPF record) identity=mailfrom; client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=willy@infradead.org; receiver=linux-nvdimm@lists.01.org Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (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 A0CF3202E53CF for ; Thu, 28 Feb 2019 20:24:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Message-Id:Date:Subject:Cc:To:From: Sender:Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=6y6M8iIIy9tvGJZ471SZvl9W7ktgva+yQLLUmyf8VCs=; b=YpFW8mYFpThrVSvtG/jqAOLs5 WyNJTM88FWMckODQiwF0Z3h4NDLLM3OL7hI0YJnp/UEVE9RYTDc/V58AaGUbFJBAgsa8N1GeBUe7x /iL3nO/zWbrW8briipDmRYGtIv/GI3XDbru0kYG5vmC8EAiqf9q+6tRVgSHawFBABkGSsU1OTJbG4 fRy/i1JfljsLAkVIgXGn92x/QwWR+pw98eMmKf6NBaBmg1/nMW5sTm+WizEPMnlGrr686eeuQh48s VFuq5qvHJqY+Ar6bRlVgs2KTMlD2m1J2M59dEb51Rc33WNiEiOszT18iHQAtSl/8kX6JDXoDZ87nf WWx0ZTngA==; Received: from willy by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gzZj8-0002SM-UC; Fri, 01 Mar 2019 04:24:50 +0000 From: Matthew Wilcox To: Piotr Balcer , Dan Williams , linux-fsdevel@vger.kernel.org, Jan Kara , linux-nvdimm@lists.01.org Subject: [PATCH] dax: Flush partial PMDs correctly Date: Thu, 28 Feb 2019 20:24:48 -0800 Message-Id: <20190301042448.6868-1-willy@infradead.org> X-Mailer: git-send-email 2.14.5 X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Matthew Wilcox MIME-Version: 1.0 Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Virus-Scanned: ClamAV using ClamSMTP The radix tree would rewind the index in an iterator to the lowest index of a multi-slot entry. The XArray iterators instead leave the index unchanged, but I overlooked that when converting DAX from the radix tree to the XArray. Adjust the index that we use for flushing to the start of the PMD range. Fixes: c1901cd33cf4 "page cache: Convert find_get_entries_tag to XArray" Reported-by: Piotr Balcer Tested-by: Dan Williams Signed-off-by: Matthew Wilcox --- fs/dax.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index 6959837cc465..f7a7af766efe 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -843,9 +843,8 @@ static void dax_entry_mkclean(struct address_space *mapping, pgoff_t index, static int dax_writeback_one(struct xa_state *xas, struct dax_device *dax_dev, struct address_space *mapping, void *entry) { - unsigned long pfn; + unsigned long pfn, index, count; long ret = 0; - size_t size; /* * A page got tagged dirty in DAX mapping? Something is seriously @@ -894,17 +893,18 @@ static int dax_writeback_one(struct xa_state *xas, struct dax_device *dax_dev, xas_unlock_irq(xas); /* - * Even if dax_writeback_mapping_range() was given a wbc->range_start - * in the middle of a PMD, the 'index' we are given will be aligned to - * the start index of the PMD, as will the pfn we pull from 'entry'. + * If dax_writeback_mapping_range() was given a wbc->range_start + * in the middle of a PMD, the 'index' we are given needs to be + * aligned to the start index of the PMD. * This allows us to flush for PMD_SIZE and not have to worry about * partial PMD writebacks. */ pfn = dax_to_pfn(entry); - size = PAGE_SIZE << dax_entry_order(entry); + count = 1UL << dax_entry_order(entry); + index = xas->xa_index &~ (count - 1); dax_entry_mkclean(mapping, xas->xa_index, pfn); - dax_flush(dax_dev, page_address(pfn_to_page(pfn)), size); + dax_flush(dax_dev, page_address(pfn_to_page(pfn)), count * PAGE_SIZE); /* * After we have flushed the cache, we can clear the dirty tag. There * cannot be new dirty data in the pfn after the flush has completed as @@ -917,8 +917,7 @@ static int dax_writeback_one(struct xa_state *xas, struct dax_device *dax_dev, xas_clear_mark(xas, PAGECACHE_TAG_DIRTY); dax_wake_entry(xas, entry, false); - trace_dax_writeback_one(mapping->host, xas->xa_index, - size >> PAGE_SHIFT); + trace_dax_writeback_one(mapping->host, xas->xa_index, count); return ret; put_unlocked: