From patchwork Tue Dec 15 12:14:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ruan Shiyang X-Patchwork-Id: 11974699 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,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 9B791C4361B for ; Tue, 15 Dec 2020 12:15:16 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4105E22475 for ; Tue, 15 Dec 2020 12:15:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4105E22475 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=cn.fujitsu.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 3012D6B0088; Tue, 15 Dec 2020 07:15:14 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 28F3C6B0089; Tue, 15 Dec 2020 07:15:14 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 156326B008A; Tue, 15 Dec 2020 07:15:14 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0138.hostedemail.com [216.40.44.138]) by kanga.kvack.org (Postfix) with ESMTP id EA4336B0088 for ; Tue, 15 Dec 2020 07:15:13 -0500 (EST) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id B1301181AEF31 for ; Tue, 15 Dec 2020 12:15:13 +0000 (UTC) X-FDA: 77595411306.14.bulb83_1804f9127423 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin14.hostedemail.com (Postfix) with ESMTP id 7C616182299A7 for ; Tue, 15 Dec 2020 12:15:13 +0000 (UTC) X-HE-Tag: bulb83_1804f9127423 X-Filterd-Recvd-Size: 4303 Received: from heian.cn.fujitsu.com (mail.cn.fujitsu.com [183.91.158.132]) by imf32.hostedemail.com (Postfix) with ESMTP for ; Tue, 15 Dec 2020 12:15:05 +0000 (UTC) X-IronPort-AV: E=Sophos;i="5.78,420,1599494400"; d="scan'208";a="102420202" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 15 Dec 2020 20:15:00 +0800 Received: from G08CNEXMBPEKD06.g08.fujitsu.local (unknown [10.167.33.206]) by cn.fujitsu.com (Postfix) with ESMTP id 7F9924CE6011; Tue, 15 Dec 2020 20:14:58 +0800 (CST) Received: from G08CNEXCHPEKD05.g08.fujitsu.local (10.167.33.203) by G08CNEXMBPEKD06.g08.fujitsu.local (10.167.33.206) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 15 Dec 2020 20:14:57 +0800 Received: from localhost.localdomain (10.167.225.141) by G08CNEXCHPEKD05.g08.fujitsu.local (10.167.33.209) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Tue, 15 Dec 2020 20:14:57 +0800 From: Shiyang Ruan To: , , , CC: , , , , , , , , , Subject: [RFC PATCH v3 7/9] dm: Introduce ->rmap() to find bdev offset Date: Tue, 15 Dec 2020 20:14:12 +0800 Message-ID: <20201215121414.253660-8-ruansy.fnst@cn.fujitsu.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201215121414.253660-1-ruansy.fnst@cn.fujitsu.com> References: <20201215121414.253660-1-ruansy.fnst@cn.fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: 7F9924CE6011.AB196 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@cn.fujitsu.com X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Pmem device could be a target of mapped device. In order to obtain superblock on the mapped device, we introduce this to translate offset from target device to md device. Currently, we implement it on linear target, which is easy to do the translation. Other targets will be supported in the future. However, some targets may not support it because of the non-linear mapping. Signed-off-by: Shiyang Ruan --- drivers/md/dm-linear.c | 8 ++++++++ include/linux/device-mapper.h | 2 ++ 2 files changed, 10 insertions(+) diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c index 00774b5d7668..7a7719e9958d 100644 --- a/drivers/md/dm-linear.c +++ b/drivers/md/dm-linear.c @@ -119,6 +119,13 @@ static void linear_status(struct dm_target *ti, status_type_t type, } } +static sector_t linear_rmap(struct dm_target *ti, sector_t offset) +{ + struct linear_c *lc = (struct linear_c *) ti->private; + + return offset - dm_target_offset(ti, lc->start); +} + static int linear_prepare_ioctl(struct dm_target *ti, struct block_device **bdev) { struct linear_c *lc = (struct linear_c *) ti->private; @@ -238,6 +245,7 @@ static struct target_type linear_target = { .ctr = linear_ctr, .dtr = linear_dtr, .map = linear_map, + .rmap = linear_rmap, .status = linear_status, .prepare_ioctl = linear_prepare_ioctl, .iterate_devices = linear_iterate_devices, diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 61a66fb8ebb3..4a2afff6937e 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -58,6 +58,7 @@ typedef void (*dm_dtr_fn) (struct dm_target *ti); * = 2: The target wants to push back the io */ typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio); +typedef sector_t (*dm_rmap_fn) (struct dm_target *ti, sector_t offset); typedef int (*dm_clone_and_map_request_fn) (struct dm_target *ti, struct request *rq, union map_info *map_context, @@ -175,6 +176,7 @@ struct target_type { dm_ctr_fn ctr; dm_dtr_fn dtr; dm_map_fn map; + dm_rmap_fn rmap; dm_clone_and_map_request_fn clone_and_map_rq; dm_release_clone_request_fn release_clone_rq; dm_endio_fn end_io;