From patchwork Sat Mar 31 04:02:36 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 10318655 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 900E060380 for ; Sat, 31 Mar 2018 04:16:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 81FC22A258 for ; Sat, 31 Mar 2018 04:16:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 765432A395; Sat, 31 Mar 2018 04:16:26 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0A33E2A258 for ; Sat, 31 Mar 2018 04:16:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751852AbeCaEMe (ORCPT ); Sat, 31 Mar 2018 00:12:34 -0400 Received: from mga06.intel.com ([134.134.136.31]:31108 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751580AbeCaEMc (ORCPT ); Sat, 31 Mar 2018 00:12:32 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 30 Mar 2018 21:12:32 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.48,383,1517904000"; d="scan'208";a="29892951" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.16]) by orsmga008.jf.intel.com with ESMTP; 30 Mar 2018 21:12:31 -0700 Subject: [PATCH v8 05/18] ext4, dax: introduce ext4_dax_aops From: Dan Williams To: linux-nvdimm@lists.01.org Cc: Theodore Ts'o , Andreas Dilger , linux-ext4@vger.kernel.org, Jan Kara , david@fromorbit.com, hch@lst.de, linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org, jack@suse.cz, snitzer@redhat.com Date: Fri, 30 Mar 2018 21:02:36 -0700 Message-ID: <152246895649.36038.5391043415273091960.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <152246892890.36038.18436540150980653229.stgit@dwillia2-desk3.amr.corp.intel.com> References: <152246892890.36038.18436540150980653229.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-2-gc94f MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In preparation for the dax implementation to start associating dax pages to inodes via page->mapping, we need to provide a 'struct address_space_operations' instance for dax. Otherwise, direct-I/O triggers incorrect page cache assumptions and warnings. Cc: "Theodore Ts'o" Cc: Andreas Dilger Cc: linux-ext4@vger.kernel.org Cc: Jan Kara Signed-off-by: Dan Williams Reviewed-by: Jan Kara --- fs/ext4/inode.c | 42 +++++++++++++++++++++++++++++++----------- 1 file changed, 31 insertions(+), 11 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index c94780075b04..249a97b19181 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2725,12 +2725,6 @@ static int ext4_writepages(struct address_space *mapping, percpu_down_read(&sbi->s_journal_flag_rwsem); trace_ext4_writepages(inode, wbc); - if (dax_mapping(mapping)) { - ret = dax_writeback_mapping_range(mapping, inode->i_sb->s_bdev, - wbc); - goto out_writepages; - } - /* * No pages to write? This is mainly a kludge to avoid starting * a transaction for special inodes like journal inode on last iput() @@ -2955,6 +2949,27 @@ static int ext4_writepages(struct address_space *mapping, return ret; } +static int ext4_dax_writepages(struct address_space *mapping, + struct writeback_control *wbc) +{ + int ret; + long nr_to_write = wbc->nr_to_write; + struct inode *inode = mapping->host; + struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb); + + if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) + return -EIO; + + percpu_down_read(&sbi->s_journal_flag_rwsem); + trace_ext4_writepages(inode, wbc); + + ret = dax_writeback_mapping_range(mapping, inode->i_sb->s_bdev, wbc); + trace_ext4_writepages_result(inode, wbc, ret, + nr_to_write - wbc->nr_to_write); + percpu_up_read(&sbi->s_journal_flag_rwsem); + return ret; +} + static int ext4_nonda_switch(struct super_block *sb) { s64 free_clusters, dirty_clusters; @@ -3857,10 +3872,6 @@ static ssize_t ext4_direct_IO(struct kiocb *iocb, struct iov_iter *iter) if (ext4_has_inline_data(inode)) return 0; - /* DAX uses iomap path now */ - if (WARN_ON_ONCE(IS_DAX(inode))) - return 0; - trace_ext4_direct_IO_enter(inode, offset, count, iov_iter_rw(iter)); if (iov_iter_rw(iter) == READ) ret = ext4_direct_IO_read(iocb, iter); @@ -3946,6 +3957,13 @@ static const struct address_space_operations ext4_da_aops = { .error_remove_page = generic_error_remove_page, }; +static const struct address_space_operations ext4_dax_aops = { + .writepages = ext4_dax_writepages, + .direct_IO = noop_direct_IO, + .set_page_dirty = noop_set_page_dirty, + .invalidatepage = noop_invalidatepage, +}; + void ext4_set_aops(struct inode *inode) { switch (ext4_inode_journal_mode(inode)) { @@ -3958,7 +3976,9 @@ void ext4_set_aops(struct inode *inode) default: BUG(); } - if (test_opt(inode->i_sb, DELALLOC)) + if (IS_DAX(inode)) + inode->i_mapping->a_ops = &ext4_dax_aops; + else if (test_opt(inode->i_sb, DELALLOC)) inode->i_mapping->a_ops = &ext4_da_aops; else inode->i_mapping->a_ops = &ext4_aops;