From patchwork Wed Jun 20 22:15:03 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ross Zwisler X-Patchwork-Id: 10478791 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 4AC0C600F6 for ; Wed, 20 Jun 2018 22:15:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3A6F428FB3 for ; Wed, 20 Jun 2018 22:15:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2ED0028FB8; Wed, 20 Jun 2018 22:15:18 +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=-2.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, 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 C2CE928FB3 for ; Wed, 20 Jun 2018 22:15:17 +0000 (UTC) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id A683C211C6099; Wed, 20 Jun 2018 15:15:16 -0700 (PDT) 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=192.55.52.93; helo=mga11.intel.com; envelope-from=ross.zwisler@linux.intel.com; receiver=linux-nvdimm@lists.01.org Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) (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 EE9C1211C608A for ; Wed, 20 Jun 2018 15:15:14 -0700 (PDT) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Jun 2018 15:15:14 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,249,1526367600"; d="scan'208";a="48655576" Received: from theros.lm.intel.com ([10.232.112.164]) by fmsmga007.fm.intel.com with ESMTP; 20 Jun 2018 15:15:14 -0700 From: Ross Zwisler To: Jan Kara , Dan Williams , Dave Chinner , Christoph Hellwig , linux-nvdimm@lists.01.org, Jeff Moyer , linux-ext4@vger.kernel.org Subject: [PATCH 2/2] ext4: handle layout changes to pinned DAX mappings Date: Wed, 20 Jun 2018 16:15:03 -0600 Message-Id: <20180620221503.25237-3-ross.zwisler@linux.intel.com> X-Mailer: git-send-email 2.14.4 In-Reply-To: <20180620221503.25237-1-ross.zwisler@linux.intel.com> References: <20180620221503.25237-1-ross.zwisler@linux.intel.com> X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Virus-Scanned: ClamAV using ClamSMTP Follow the lead of xfs_break_dax_layouts() and add synchronization between operations in ext4 which remove blocks from an inode (hole punch, truncate down, etc.) and pages which are pinned due to DAX DMA operations. Signed-off-by: Ross Zwisler Reviewed-by: Jan Kara --- fs/ext4/ext4.h | 1 + fs/ext4/extents.c | 12 ++++++++++++ fs/ext4/inode.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ fs/ext4/truncate.h | 1 + 4 files changed, 62 insertions(+) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 0b127853c584..34bccd64d83d 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2460,6 +2460,7 @@ extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *); extern int ext4_inode_attach_jinode(struct inode *inode); extern int ext4_can_truncate(struct inode *inode); extern int ext4_truncate(struct inode *); +extern int ext4_break_layouts(struct inode *); extern int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length); extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks); extern void ext4_set_inode_flags(struct inode *); diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 0057fe3f248d..a6aef06f455b 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4820,6 +4820,13 @@ static long ext4_zero_range(struct file *file, loff_t offset, * released from page cache. */ down_write(&EXT4_I(inode)->i_mmap_sem); + + ret = ext4_break_layouts(inode); + if (ret) { + up_write(&EXT4_I(inode)->i_mmap_sem); + goto out_mutex; + } + ret = ext4_update_disksize_before_punch(inode, offset, len); if (ret) { up_write(&EXT4_I(inode)->i_mmap_sem); @@ -5493,6 +5500,11 @@ int ext4_collapse_range(struct inode *inode, loff_t offset, loff_t len) * page cache. */ down_write(&EXT4_I(inode)->i_mmap_sem); + + ret = ext4_break_layouts(inode); + if (ret) + goto out_mmap; + /* * Need to round down offset to be aligned with page size boundary * for page size > block size. diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 2ea07efbe016..c795e5118745 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4193,6 +4193,41 @@ int ext4_update_disksize_before_punch(struct inode *inode, loff_t offset, return 0; } +static void ext4_wait_dax_page(struct ext4_inode_info *ei, bool *did_unlock) +{ + *did_unlock = true; + up_write(&ei->i_mmap_sem); + schedule(); + down_write(&ei->i_mmap_sem); +} + +int ext4_break_layouts(struct inode *inode) +{ + struct ext4_inode_info *ei = EXT4_I(inode); + struct page *page; + bool retry; + int error; + + if (unlikely(!rwsem_is_locked(&ei->i_mmap_sem))) { + WARN_ON_ONCE(1); + return -EINVAL; + } + + do { + retry = false; + page = dax_layout_busy_page(inode->i_mapping); + if (!page) + return 0; + + error = ___wait_var_event(&page->_refcount, + atomic_read(&page->_refcount) == 1, + TASK_INTERRUPTIBLE, 0, 0, + ext4_wait_dax_page(ei, &retry)); + } while (error == 0 && retry); + + return error; +} + /* * ext4_punch_hole: punches a hole in a file by releasing the blocks * associated with the given offset and length @@ -4266,6 +4301,11 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length) * page cache. */ down_write(&EXT4_I(inode)->i_mmap_sem); + + ret = ext4_break_layouts(inode); + if (ret) + goto out_dio; + first_block_offset = round_up(offset, sb->s_blocksize); last_block_offset = round_down((offset + length), sb->s_blocksize) - 1; @@ -5554,6 +5594,14 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr) ext4_wait_for_tail_page_commit(inode); } down_write(&EXT4_I(inode)->i_mmap_sem); + + rc = ext4_break_layouts(inode); + if (rc) { + up_write(&EXT4_I(inode)->i_mmap_sem); + error = rc; + goto err_out; + } + /* * Truncate pagecache after we've waited for commit * in data=journal mode to make pages freeable. diff --git a/fs/ext4/truncate.h b/fs/ext4/truncate.h index 0cb13badf473..a3b78241e9f6 100644 --- a/fs/ext4/truncate.h +++ b/fs/ext4/truncate.h @@ -12,6 +12,7 @@ static inline void ext4_truncate_failed_write(struct inode *inode) { down_write(&EXT4_I(inode)->i_mmap_sem); + ext4_break_layouts(inode); truncate_inode_pages(inode->i_mapping, inode->i_size); ext4_truncate(inode); up_write(&EXT4_I(inode)->i_mmap_sem);