From patchwork Fri Jan 28 00:25:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 12727623 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E480DC35274 for ; Fri, 28 Jan 2022 00:26:36 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 23A8E6B0074; Thu, 27 Jan 2022 19:26:31 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 020B96B0072; Thu, 27 Jan 2022 19:26:30 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D67926B0074; Thu, 27 Jan 2022 19:26:30 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0210.hostedemail.com [216.40.44.210]) by kanga.kvack.org (Postfix) with ESMTP id 8DF926B0075 for ; Thu, 27 Jan 2022 19:26:30 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 4DCE51820BA6C for ; Fri, 28 Jan 2022 00:26:30 +0000 (UTC) X-FDA: 79077804540.28.FA900D5 Received: from ale.deltatee.com (ale.deltatee.com [204.191.154.188]) by imf26.hostedemail.com (Postfix) with ESMTP id E8EA1140006 for ; Fri, 28 Jan 2022 00:26:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:MIME-Version:References:In-Reply-To: Message-Id:Date:Cc:To:From:content-disposition; bh=V/05GzOrgOl/UyUBKWfOm8imWYPgACNjFeMcbOGPBpc=; b=tLr1nf2CgmrXo3UylgDfejDLSA e7xAEnjM8MryfrJln0g42DeGCO4Tau2qcnIyG0UAgpBgHzPO155HM9LjSV55iVUuzjEEw/Aw0kTPf VoJL03pfwmN1Z9/T5DG4l3j86mVC9N/D0lVn2KL/Fre6jUPLw23Ngw4A2wNNmC+Cj7XRA3I29ze9G +/3EKIHzq2e29X3Gi5t4Ar5qNunlgnF/Jn2SL3QEX2T8gRsF9UlXfYMUHtDay/KcBT+wL1lQ/ToF1 Zkql/xSSCKKCXzk8vdecuhOKVjmehApGrLxNwOwyAj8sVjRx6Ycgw1RCx9yNmydD9HwLubB9aHPm/ h739BC5Q==; Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nDF5p-005OcX-U8; Thu, 27 Jan 2022 17:26:23 -0700 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.94.2) (envelope-from ) id 1nDF5m-0001cD-7l; Thu, 27 Jan 2022 17:26:18 -0700 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-pci@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org Cc: Stephen Bates , Christoph Hellwig , Dan Williams , Jason Gunthorpe , =?utf-8?q?Christian_K=C3=B6nig?= , John Hubbard , Don Dutile , Matthew Wilcox , Daniel Vetter , Jakowski Andrzej , Minturn Dave B , Jason Ekstrand , Dave Hansen , Xiong Jianxin , Bjorn Helgaas , Ira Weiny , Robin Murphy , Martin Oliveira , Chaitanya Kulkarni , Ralph Campbell , Alex Sierra , Theodore Ts'o , "Darrick J . Wong" Date: Thu, 27 Jan 2022 17:25:51 -0700 Message-Id: <20220128002614.6136-2-logang@deltatee.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220128002614.6136-1-logang@deltatee.com> References: <20220128002614.6136-1-logang@deltatee.com> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-pci@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, sbates@raithlin.com, hch@lst.de, jgg@ziepe.ca, ddutile@redhat.com, willy@infradead.org, daniel.vetter@ffwll.ch, jason@jlekstrand.net, dave.hansen@linux.intel.com, dan.j.williams@intel.com, andrzej.jakowski@intel.com, dave.b.minturn@intel.com, jianxin.xiong@intel.com, ira.weiny@intel.com, robin.murphy@arm.com, martin.oliveira@eideticom.com, ckulkarnilinux@gmail.com, jhubbard@nvidia.com, rcampbell@nvidia.com, christian.koenig@amd.com, alex.sierra@amd.com, tytso@mit.edu, helgaas@kernel.org, djwong@kernel.org X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v5 01/24] ext4/xfs: add page refcount helper X-SA-Exim-Version: 4.2.1 (built Sat, 13 Feb 2021 17:57:42 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) X-Stat-Signature: djt1i7hdmso6j5r4ipz7c4mkafczwdor X-Rspam-User: nil Authentication-Results: imf26.hostedemail.com; dkim=pass header.d=deltatee.com header.s=20200525 header.b=tLr1nf2C; spf=pass (imf26.hostedemail.com: domain of gunthorp@deltatee.com designates 204.191.154.188 as permitted sender) smtp.mailfrom=gunthorp@deltatee.com; dmarc=pass (policy=none) header.from=deltatee.com X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: E8EA1140006 X-HE-Tag: 1643329589-611042 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Ralph Campbell There are several places where ZONE_DEVICE struct pages assume a reference count == 1 means the page is idle and free. Instead of open coding this, add a helper function to hide this detail. Signed-off-by: Ralph Campbell Signed-off-by: Alex Sierra Reviewed-by: Christoph Hellwig Acked-by: Theodore Ts'o Acked-by: Darrick J. Wong Reviewed-by: Chaitanya Kulkarni --- fs/dax.c | 4 ++-- fs/ext4/inode.c | 5 +---- fs/fuse/dax.c | 4 +--- fs/xfs/xfs_file.c | 4 +--- include/linux/dax.h | 10 ++++++++++ 5 files changed, 15 insertions(+), 12 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index cd03485867a7..d9b856cf6436 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -369,7 +369,7 @@ static void dax_disassociate_entry(void *entry, struct address_space *mapping, for_each_mapped_pfn(entry, pfn) { struct page *page = pfn_to_page(pfn); - WARN_ON_ONCE(trunc && page_ref_count(page) > 1); + WARN_ON_ONCE(trunc && !dax_page_unused(page)); WARN_ON_ONCE(page->mapping && page->mapping != mapping); page->mapping = NULL; page->index = 0; @@ -383,7 +383,7 @@ static struct page *dax_busy_page(void *entry) for_each_mapped_pfn(entry, pfn) { struct page *page = pfn_to_page(pfn); - if (page_ref_count(page) > 1) + if (!dax_page_unused(page)) return page; } return NULL; diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 5f79d265d06a..99e3ed7bcd06 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3899,10 +3899,7 @@ int ext4_break_layouts(struct inode *inode) if (!page) return 0; - error = ___wait_var_event(&page->_refcount, - atomic_read(&page->_refcount) == 1, - TASK_INTERRUPTIBLE, 0, 0, - ext4_wait_dax_page(inode)); + error = dax_wait_page(inode, page, ext4_wait_dax_page); } while (error == 0); return error; diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c index 182b24a14804..f8b3f30d2303 100644 --- a/fs/fuse/dax.c +++ b/fs/fuse/dax.c @@ -676,9 +676,7 @@ static int __fuse_dax_break_layouts(struct inode *inode, bool *retry, return 0; *retry = true; - return ___wait_var_event(&page->_refcount, - atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE, - 0, 0, fuse_wait_dax_page(inode)); + return dax_wait_page(inode, page, fuse_wait_dax_page); } /* dmap_end == 0 leads to unmapping of whole file */ diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 22ad207bedf4..57a440666935 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -859,9 +859,7 @@ xfs_break_dax_layouts( return 0; *retry = true; - return ___wait_var_event(&page->_refcount, - atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE, - 0, 0, xfs_wait_dax_page(inode)); + return dax_wait_page(inode, page, xfs_wait_dax_page); } int diff --git a/include/linux/dax.h b/include/linux/dax.h index 9fc5f99a0ae2..479939b3be40 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -201,6 +201,16 @@ static inline bool dax_mapping(struct address_space *mapping) return mapping->host && IS_DAX(mapping->host); } +static inline bool dax_page_unused(struct page *page) +{ + return page_ref_count(page) == 1; +} + +#define dax_wait_page(_inode, _page, _wait_cb) \ + ___wait_var_event(&(_page)->_refcount, \ + dax_page_unused(_page), \ + TASK_INTERRUPTIBLE, 0, 0, _wait_cb(_inode)) + #ifdef CONFIG_DEV_DAX_HMEM_DEVICES void hmem_register_device(int target_nid, struct resource *r); #else