From patchwork Tue Oct 24 06:44:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 13433967 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 65015F9E4 for ; Tue, 24 Oct 2023 06:44:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="5ABpqDa1" Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A0F0B118; Mon, 23 Oct 2023 23:44:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=SRYZHQ04hacwuEwpWKzRe5AbE87Phgtpy62POhugK7g=; b=5ABpqDa1lh0phh7GpUJ2sCEBTX euFvql4TUCV/4em6WAf5iTj1UtDv9YFIM77swuiFHaaJtPUr6D31ivY+9UgDgRmHxWEyXVkHgnPJw MHbflhwJZYn4ZQZGt1ZJgsg94+XN27VjVlwZnEBem3BKEPUjPtKfmPs4YYGz8XFw6nL7qrBQvCVYg tfDSE8HmNOIwHYS+yN694/z9224F69MJ/AcbYVUUx1E9gcspA4wQK7jxQ9ojSlFF/AqBK8kg9pev8 XIsk4eYKOlpr7BGIyPvNwFWqAwZWh9L7/h5o6inPZQJsuzHt/XwR0n8PoPG/yTzSKjREQhC9Z+xjl HWg+mOVw==; Received: from 2a02-8389-2341-5b80-39d3-4735-9a3c-88d8.cable.dynamic.v6.surfer.at ([2a02:8389:2341:5b80:39d3:4735:9a3c:88d8] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1qvB9K-0090RZ-2f; Tue, 24 Oct 2023 06:44:23 +0000 From: Christoph Hellwig To: Jens Axboe , Matthew Wilcox Cc: Ilya Dryomov , Andrew Morton , linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 1/3] filemap: add a per-mapping stable writes flag Date: Tue, 24 Oct 2023 08:44:14 +0200 Message-Id: <20231024064416.897956-2-hch@lst.de> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231024064416.897956-1-hch@lst.de> References: <20231024064416.897956-1-hch@lst.de> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html folio_wait_stable waits for writeback to finish before modifying the contents of a folio again, e.g. to support check summing of the data in the block integrity code. Currently this behavior is controlled by the SB_I_STABLE_WRITES flag on the super_block, which means it is uniform for the entire file system. This is wrong for the block device pseudofs which is shared by all block devices, or file systems that can use multiple devices like XFS witht the RT subvolume or btrfs (although btrfs currently reimplements folio_wait_stable anyway). Add a per-address_space AS_STABLE_WRITES flag to control the behavior in a more fine grained way. The existing SB_I_STABLE_WRITES is kept to initialize AS_STABLE_WRITES to the existing default which covers most cases. Signed-off-by: Christoph Hellwig Reviewed-by: Matthew Wilcox (Oracle) Tested-by: Ilya Dryomov Reviewed-by: Darrick J. Wong --- fs/inode.c | 2 ++ include/linux/pagemap.h | 17 +++++++++++++++++ mm/page-writeback.c | 2 +- 3 files changed, 20 insertions(+), 1 deletion(-) diff --git a/fs/inode.c b/fs/inode.c index 84bc3c76e5ccb5..ae1a6410b53d7e 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -215,6 +215,8 @@ int inode_init_always(struct super_block *sb, struct inode *inode) lockdep_set_class_and_name(&mapping->invalidate_lock, &sb->s_type->invalidate_lock_key, "mapping.invalidate_lock"); + if (sb->s_iflags & SB_I_STABLE_WRITES) + mapping_set_stable_writes(mapping); inode->i_private = NULL; inode->i_mapping = mapping; INIT_HLIST_HEAD(&inode->i_dentry); /* buggered by rcu freeing */ diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 351c3b7f93a14e..8c9608b217b000 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -204,6 +204,8 @@ enum mapping_flags { AS_NO_WRITEBACK_TAGS = 5, AS_LARGE_FOLIO_SUPPORT = 6, AS_RELEASE_ALWAYS, /* Call ->release_folio(), even if no private data */ + AS_STABLE_WRITES, /* must wait for writeback before modifying + folio contents */ }; /** @@ -289,6 +291,21 @@ static inline void mapping_clear_release_always(struct address_space *mapping) clear_bit(AS_RELEASE_ALWAYS, &mapping->flags); } +static inline bool mapping_stable_writes(const struct address_space *mapping) +{ + return test_bit(AS_STABLE_WRITES, &mapping->flags); +} + +static inline void mapping_set_stable_writes(struct address_space *mapping) +{ + set_bit(AS_STABLE_WRITES, &mapping->flags); +} + +static inline void mapping_clear_stable_writes(struct address_space *mapping) +{ + clear_bit(AS_STABLE_WRITES, &mapping->flags); +} + static inline gfp_t mapping_gfp_mask(struct address_space * mapping) { return mapping->gfp_mask; diff --git a/mm/page-writeback.c b/mm/page-writeback.c index b8d3d7040a506a..4656534b8f5cc6 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -3110,7 +3110,7 @@ EXPORT_SYMBOL_GPL(folio_wait_writeback_killable); */ void folio_wait_stable(struct folio *folio) { - if (folio_inode(folio)->i_sb->s_iflags & SB_I_STABLE_WRITES) + if (mapping_stable_writes(folio_mapping(folio))) folio_wait_writeback(folio); } EXPORT_SYMBOL_GPL(folio_wait_stable);