From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 74CC8C43441 for ; Wed, 21 Nov 2018 03:27:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1ECDF21104 for ; Wed, 21 Nov 2018 03:27:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=zoho.com header.i=yehs2007@zoho.com header.b="TWBHnOC7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1ECDF21104 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=zoho.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728126AbeKUOAR (ORCPT ); Wed, 21 Nov 2018 09:00:17 -0500 Received: from sender-pp-092.zoho.com ([135.84.80.237]:25414 "EHLO sender-pp-092.zoho.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727069AbeKUOAN (ORCPT ); Wed, 21 Nov 2018 09:00:13 -0500 ARC-Seal: i=1; a=rsa-sha256; t=1542770838; cv=none; d=zoho.com; s=zohoarc; b=CHGL1Zk2KmvmqLdhGLV1ZTpXSyFGAsj3XhcGtsJLghv8eEbdWs1CRZSBYRR7iUq6XnFtt4jJ49PBs6jrt6M92pXMwmIqIq6Gc+MqG6K2B39UsquNgmmxqAXZ+ddrAb2AGEz4JjxT7GOPhv142I6ViEbkknEaUeyvuvML4c5tk1Q= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1542770838; h=Cc:Date:From:In-Reply-To:Message-ID:References:Subject:To:ARC-Authentication-Results; bh=x5kiuOrmgRFLAeD2AslmuJBuZpUUO1Oydcg13gKN4JY=; b=ZfpysI/otcY8lDMrhinqsV0xzeastr8IbvMqQy83SKWnNwrb3KyfcWafA96+EznvH1poweMg7e6rusysoJuTMFqh2VhurtqgKfYZsZdrk0OgiSe+TbCCVjamPFHBa2n2RA+0K1O4b3KsbysLL8khA6chTLCoPGGEoMkq70meaWA= ARC-Authentication-Results: i=1; mx.zoho.com; dkim=pass header.i=zoho.com; spf=pass smtp.mailfrom=yehs2007@zoho.com; dmarc=pass header.from= header.from= DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=zapps768; d=zoho.com; h=from:to:cc:subject:date:message-id:in-reply-to:references; b=uMP3wH7Fa043JOBhcF3XHpl+6mC/ihtrgE7BQmN9GQQUUbUBCk2sg/hXgaiBwp51EnSnNbSDtkFs +4Ixrhq3TWeCQES79gN8sUmYrRZQtSXO8YOJ+m+uRw2H71s025/n DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1542770838; s=default; d=zoho.com; i=yehs2007@zoho.com; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; l=3918; bh=x5kiuOrmgRFLAeD2AslmuJBuZpUUO1Oydcg13gKN4JY=; b=TWBHnOC7CUsEFrq3IFREfEbQUz02Ook1AIiO8SEgDDJYP5eugJCXzO5Bq9oiO3jx NFefZbzoHEpuugm44PAgUqteA9LIoFNh6lc2a/rxHk7spoZXxpG5rWXv4OuwihY0YlP 98JP9KE3pjVrBw8WFSOARBfnWErR4syDJvOIv/6c= Received: from YEHS1XR956R00D1.lenovo.com (58.243.153.247 [58.243.153.247]) by mx.zohomail.com with SMTPS id 1542770837567242.21765413287517; Tue, 20 Nov 2018 19:27:17 -0800 (PST) From: Huaisheng Ye To: linux-nvdimm@lists.01.org, agk@redhat.com, snitzer@redhat.com, dm-devel@redhat.com, dan.j.williams@intel.com, willy@infradead.org, zwisler@kernel.org, jack@suse.cz, dave.jiang@intel.com, vishal.l.verma@intel.com Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, chengnt@lenovo.com, Huaisheng Ye Subject: [RFC PATCH v2 1/3] dm: enable dax_operations for dm-snapshot Date: Wed, 21 Nov 2018 11:27:00 +0800 Message-Id: <20181121032702.3048-2-yehs2007@zoho.com> X-Mailer: git-send-email 2.17.0.windows.1 In-Reply-To: <20181121032702.3048-1-yehs2007@zoho.com> References: <20181121032702.3048-1-yehs2007@zoho.com> X-ZohoMailClient: External Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Huaisheng Ye Reconstruct origin_dax_direct_access and expand functions origin_dax_copy_to/from_iter for DAX operations of dm-snapshot. Here is the call trace of origin_dax_copy_to_iter, origin_dax_copy_to_iter will callin dm-linear (-real) for further dax_operation. [518597.924019] Call Trace: [518597.927320] dump_stack+0x65/0x7e [518597.931592] origin_dax_copy_to_iter+0x51/0x78 [dm_snapshot] [518597.938494] dm_dax_copy_to_iter+0x86/0xc5 [dm_mod] [518597.944519] dax_copy_to_iter+0x27/0x29 [518597.949371] dax_iomap_actor+0x264/0x326 [518597.954308] ? trace_event_raw_event_dax_pmd_load_hole_class+0xd0/0xd0 [518597.962159] iomap_apply+0xc7/0x128 [518597.966609] ? trace_event_raw_event_dax_pmd_load_hole_class+0xd0/0xd0 [518597.974447] dax_iomap_rw+0x66/0xa8 [518597.978893] ? trace_event_raw_event_dax_pmd_load_hole_class+0xd0/0xd0 [518597.986741] ext2_file_read_iter+0x4f/0x83 [ext2] [518597.992552] __vfs_read+0x130/0x168 [518597.997001] vfs_read+0x92/0x146 [518598.001155] ksys_read+0x4f/0xa5 [518598.005308] __x64_sys_read+0x16/0x18 [518598.009942] do_syscall_64+0x88/0x15f [518598.014575] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Signed-off-by: Huaisheng Ye --- drivers/md/dm-snap.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 49 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index ae4b33d..714e26f 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "dm.h" @@ -2316,13 +2317,57 @@ static int origin_map(struct dm_target *ti, struct bio *bio) return do_origin(o->dev, bio); } +#if IS_ENABLED(CONFIG_DAX_DRIVER) static long origin_dax_direct_access(struct dm_target *ti, pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn) { - DMWARN("device does not support dax."); - return -EIO; + long ret = 0; + struct dm_origin *o = ti->private; + struct block_device *bdev = o->dev->bdev; + struct dax_device *dax_dev = o->dev->dax_dev; + sector_t sector = pgoff * PAGE_SECTORS; + + ret = bdev_dax_pgoff(bdev, sector, nr_pages * PAGE_SIZE, &pgoff); + if (ret) + return ret; + + return dax_direct_access(dax_dev, pgoff, nr_pages, kaddr, pfn); +} + +static size_t origin_dax_copy_from_iter(struct dm_target *ti, pgoff_t pgoff, + void *addr, size_t bytes, struct iov_iter *i) +{ + struct dm_origin *o = ti->private; + struct block_device *bdev = o->dev->bdev; + struct dax_device *dax_dev = o->dev->dax_dev; + sector_t sector = pgoff * PAGE_SECTORS; + + if (bdev_dax_pgoff(bdev, sector, ALIGN(bytes, PAGE_SIZE), &pgoff)) + return 0; + + return dax_copy_from_iter(dax_dev, pgoff, addr, bytes, i); } +static size_t origin_dax_copy_to_iter(struct dm_target *ti, pgoff_t pgoff, + void *addr, size_t bytes, struct iov_iter *i) +{ + struct dm_origin *o = ti->private; + struct block_device *bdev = o->dev->bdev; + struct dax_device *dax_dev = o->dev->dax_dev; + sector_t sector = pgoff * PAGE_SECTORS; + + if (bdev_dax_pgoff(bdev, sector, ALIGN(bytes, PAGE_SIZE), &pgoff)) + return 0; + + return dax_copy_to_iter(dax_dev, pgoff, addr, bytes, i); +} + +#else +#define origin_dax_direct_access NULL +#define origin_dax_copy_from_iter NULL +#define origin_dax_copy_to_iter NULL +#endif + /* * Set the target "max_io_len" field to the minimum of all the snapshots' * chunk sizes. @@ -2383,6 +2428,8 @@ static int origin_iterate_devices(struct dm_target *ti, .status = origin_status, .iterate_devices = origin_iterate_devices, .direct_access = origin_dax_direct_access, + .dax_copy_to_iter = origin_dax_copy_to_iter, + .dax_copy_from_iter = origin_dax_copy_from_iter, }; static struct target_type snapshot_target = { -- 1.8.3.1