From patchwork Mon Aug 16 06:03:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shiyang Ruan X-Patchwork-Id: 12437821 Received: from heian.cn.fujitsu.com (mail.cn.fujitsu.com [183.91.158.132]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A67856D13 for ; Mon, 16 Aug 2021 06:05:21 +0000 (UTC) IronPort-HdrOrdr: A9a23:oMiQhKGhF1zFyE6epLqE1MeALOsnbusQ8zAXPiFKOHhom6mj+vxG88506faKslwssR0b+OxoW5PwJE80l6QFgrX5VI3KNGbbUQCTXeNfBOXZowHIKmnX8+5x8eNaebFiNduYNzNHpPe/zA6mM9tI+rW6zJw= X-IronPort-AV: E=Sophos;i="5.84,324,1620662400"; d="scan'208";a="112944832" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 16 Aug 2021 14:04:10 +0800 Received: from G08CNEXMBPEKD04.g08.fujitsu.local (unknown [10.167.33.201]) by cn.fujitsu.com (Postfix) with ESMTP id 031C54D0D4BB; Mon, 16 Aug 2021 14:04:08 +0800 (CST) Received: from G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.85) by G08CNEXMBPEKD04.g08.fujitsu.local (10.167.33.201) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Mon, 16 Aug 2021 14:04:04 +0800 Received: from irides.mr.mr.mr (10.167.225.141) by G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.23 via Frontend Transport; Mon, 16 Aug 2021 14:04:01 +0800 From: Shiyang Ruan To: , , CC: , , , , , , , , Subject: [PATCH v7 0/8] fsdax,xfs: Add reflink&dedupe support for fsdax Date: Mon, 16 Aug 2021 14:03:51 +0800 Message-ID: <20210816060359.1442450-1-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.32.0 Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-yoursite-MailScanner-ID: 031C54D0D4BB.A521A X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com X-Spam-Status: No This patchset is attempt to add CoW support for fsdax, and take XFS, which has both reflink and fsdax feature, as an example. Changes from V6: - Rebased on switch iomap to an iterator model v2[1] - Replace iomap_apply2() with iomap_iter2() because of the new model - Introduce dax_iomap_ops and dax_iomap_ops->actor_end() to handle the end of CoW before iomap_ops->iomap_end() One of the key mechanism need to be implemented in fsdax is CoW. Copy the data from srcmap before we actually write data to the destance iomap. And we just copy range in which data won't be changed. Another mechanism is range comparison. In page cache case, readpage() is used to load data on disk to page cache in order to be able to compare data. In fsdax case, readpage() does not work. So, we need another compare data with direct access support. With the two mechanisms implemented in fsdax, we are able to make reflink and fsdax work together in XFS. (Rebased on v5.14-rc4 and Christoph's "switch iomap to an iterator model v2"[1]) [1]: https://lore.kernel.org/linux-xfs/20210809061244.1196573-1-hch@lst.de/ == Shiyang Ruan (8): fsdax: Output address in dax_iomap_pfn() and rename it fsdax: Introduce dax_iomap_cow_copy() fsdax: Replace mmap entry in case of CoW fsdax: Add dax_iomap_cow_copy() for dax_iomap_zero iomap: Introduce iomap_iter2 for two files fsdax: Dedup file range to use a compare function fsdax: Introduce dax_iomap_ops for end of reflink fs/xfs: Add dax dedupe support fs/dax.c | 307 ++++++++++++++++++++++++++++++++++++----- fs/ext2/ext2.h | 3 + fs/ext2/file.c | 6 +- fs/ext2/inode.c | 11 +- fs/ext4/ext4.h | 3 + fs/ext4/file.c | 6 +- fs/ext4/inode.c | 13 +- fs/iomap/buffered-io.c | 7 +- fs/iomap/core.c | 51 +++++++ fs/remap_range.c | 39 ++++-- fs/xfs/xfs_bmap_util.c | 3 +- fs/xfs/xfs_file.c | 10 +- fs/xfs/xfs_inode.c | 57 ++++++++ fs/xfs/xfs_inode.h | 1 + fs/xfs/xfs_iomap.c | 36 ++++- fs/xfs/xfs_iomap.h | 33 +++++ fs/xfs/xfs_iops.c | 7 +- fs/xfs/xfs_reflink.c | 15 +- include/linux/dax.h | 32 ++++- include/linux/fs.h | 12 +- include/linux/iomap.h | 3 + 21 files changed, 570 insertions(+), 85 deletions(-)