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=-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 AD760C4338F for ; Fri, 30 Jul 2021 10:02:32 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 47B3760E93 for ; Fri, 30 Jul 2021 10:02:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 47B3760E93 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=fujitsu.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 84A826B0078; Fri, 30 Jul 2021 06:02:28 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7D1D26B007B; Fri, 30 Jul 2021 06:02:28 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6C2AC6B007D; Fri, 30 Jul 2021 06:02:28 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0025.hostedemail.com [216.40.44.25]) by kanga.kvack.org (Postfix) with ESMTP id 5268F6B0078 for ; Fri, 30 Jul 2021 06:02:28 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 0AD201813459E for ; Fri, 30 Jul 2021 10:02:28 +0000 (UTC) X-FDA: 78418814376.10.B5CB542 Received: from heian.cn.fujitsu.com (mail.cn.fujitsu.com [183.91.158.132]) by imf02.hostedemail.com (Postfix) with ESMTP id 3C93F70038C0 for ; Fri, 30 Jul 2021 10:02:26 +0000 (UTC) IronPort-HdrOrdr: =?us-ascii?q?A9a23=3AMRBiS6u+ze944rzB4eEYS/Vi7skDntV00zEX?= =?us-ascii?q?/kB9WHVpmszxra6TdZMgpHvJYVcqKRYdcL+7WJVoLUmxyXcX2/h1AV7BZniEhI?= =?us-ascii?q?LAFugLhuGO/9SKIUzDH4BmupuIC5IOauEYE2IK9vrS0U2pFco62tmb/OSNjefa?= =?us-ascii?q?9X1kSgZncMhbnn5EIzfeAktrXxNHGJZ8MJKd4/BMrz2mdW9SQd+8AhA+LpD+ju?= =?us-ascii?q?yOhJT7egQHGhJizAGPiAmj4Ln8HwPd/jp2aUIo/Ysf?= X-IronPort-AV: E=Sophos;i="5.84,281,1620662400"; d="scan'208";a="112074026" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 30 Jul 2021 18:02:26 +0800 Received: from G08CNEXMBPEKD05.g08.fujitsu.local (unknown [10.167.33.204]) by cn.fujitsu.com (Postfix) with ESMTP id C023B4D0D4A3; Fri, 30 Jul 2021 18:02:20 +0800 (CST) Received: from G08CNEXJMPEKD02.g08.fujitsu.local (10.167.33.202) by G08CNEXMBPEKD05.g08.fujitsu.local (10.167.33.204) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Fri, 30 Jul 2021 18:02:17 +0800 Received: from G08CNEXCHPEKD09.g08.fujitsu.local (10.167.33.85) by G08CNEXJMPEKD02.g08.fujitsu.local (10.167.33.202) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Fri, 30 Jul 2021 18:02:15 +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; Fri, 30 Jul 2021 18:02:13 +0800 From: Shiyang Ruan To: , , , , , CC: , , , , , Subject: [PATCH RESEND v6 7/9] dm: Introduce ->rmap() to find bdev offset Date: Fri, 30 Jul 2021 18:01:56 +0800 Message-ID: <20210730100158.3117319-8-ruansy.fnst@fujitsu.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210730100158.3117319-1-ruansy.fnst@fujitsu.com> References: <20210730100158.3117319-1-ruansy.fnst@fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain X-yoursite-MailScanner-ID: C023B4D0D4A3.A24E5 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: ruansy.fnst@fujitsu.com X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 3C93F70038C0 Authentication-Results: imf02.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=fujitsu.com (policy=none); spf=none (imf02.hostedemail.com: domain of ruansy.fnst@fujitsu.com has no SPF policy when checking 183.91.158.132) smtp.mailfrom=ruansy.fnst@fujitsu.com X-Stat-Signature: bap356y1o4i6qqbrrg8xk1tgm1h6iedf X-HE-Tag: 1627639346-817405 Content-Transfer-Encoding: quoted-printable 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 find out the global location on a mapped device, we introduce this to translate offset from target device to mapped 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 --- block/genhd.c | 56 +++++++++++++++++++++++++++++++++++ drivers/md/dm-linear.c | 20 +++++++++++++ include/linux/device-mapper.h | 5 ++++ include/linux/genhd.h | 1 + 4 files changed, 82 insertions(+) diff --git a/block/genhd.c b/block/genhd.c index af4d2ab4a633..7a595da0cbec 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -669,6 +669,62 @@ void blk_request_module(dev_t devt) request_module("block-major-%d", MAJOR(devt)); } =20 +/* + * bdget_disk - do bdget() by gendisk and partition number + * @disk: gendisk of interest + * @partno: partition number + * + * Find partition @partno from @disk, do bdget() on it. + * + * CONTEXT: + * Don't care. + * + * RETURNS: + * Resulting block_device on success, NULL on failure. + */ +static inline struct block_device *bdget_disk(struct gendisk *disk, int = partno) +{ + struct block_device *bdev =3D NULL; + + rcu_read_lock(); + bdev =3D xa_load(&disk->part_tbl, partno); + if (bdev && !bdgrab(bdev)) + bdev =3D NULL; + rcu_read_unlock(); + + return bdev; +} + +/** + * bdget_disk_sector - get block device by given sector number + * @disk: gendisk of interest + * @sector: sector number + * + * RETURNS: the found block device where sector locates in + */ +struct block_device *bdget_disk_sector(struct gendisk *disk, sector_t se= ctor) +{ + struct block_device *part =3D NULL, *p; + unsigned long idx; + + rcu_read_lock(); + xa_for_each(&disk->part_tbl, idx, p) { + if (p->bd_partno =3D=3D 0) + continue; + if (p->bd_start_sect <=3D sector && + sector < p->bd_start_sect + bdev_nr_sectors(p)) { + part =3D p; + break; + } + } + rcu_read_unlock(); + if (!part) + part =3D disk->part0; + + return bdget_disk(disk, part->bd_partno); +} +EXPORT_SYMBOL(bdget_disk_sector); + /* * print a full list of all partitions - intended for places where the r= oot * filesystem can't be mounted and thus to give the victim some idea of = what diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c index c91f1e2e2f65..d28577bd358b 100644 --- a/drivers/md/dm-linear.c +++ b/drivers/md/dm-linear.c @@ -5,6 +5,7 @@ */ =20 #include "dm.h" +#include "dm-core.h" #include #include #include @@ -119,6 +120,24 @@ static void linear_status(struct dm_target *ti, stat= us_type_t type, } } =20 +static int linear_rmap(struct dm_target *ti, sector_t offset, + rmap_callout_fn fn, void *data) +{ + struct linear_c *lc =3D (struct linear_c *) ti->private; + struct mapped_device *md =3D ti->table->md; + struct block_device *bdev; + sector_t disk_sect =3D offset - dm_target_offset(ti, lc->start); + int rc =3D -ENODEV; + + bdev =3D bdget_disk_sector(md->disk, offset); + if (!bdev) + return rc; + + rc =3D fn(ti, bdev, disk_sect, data); + bdput(bdev); + return rc; +} + static int linear_prepare_ioctl(struct dm_target *ti, struct block_devic= e **bdev) { struct linear_c *lc =3D (struct linear_c *) ti->private; @@ -235,6 +254,7 @@ static struct target_type linear_target =3D { .ctr =3D linear_ctr, .dtr =3D linear_dtr, .map =3D linear_map, + .rmap =3D linear_rmap, .status =3D linear_status, .prepare_ioctl =3D linear_prepare_ioctl, .iterate_devices =3D linear_iterate_devices, diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.= h index 7457d49acf9a..4069983c4618 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -58,6 +58,10 @@ typedef void (*dm_dtr_fn) (struct dm_target *ti); * =3D 2: The target wants to push back the io */ typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio); +typedef int (*rmap_callout_fn) (struct dm_target *ti, struct block_devic= e *bdev, + sector_t sect, void *data); +typedef int (*dm_rmap_fn) (struct dm_target *ti, sector_t offset, + rmap_callout_fn fn, void *data); typedef int (*dm_clone_and_map_request_fn) (struct dm_target *ti, struct request *rq, union map_info *map_context, @@ -184,6 +188,7 @@ 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; diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 13b34177cc85..7de6fdc14de6 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -223,6 +223,7 @@ static inline void add_disk_no_queue_reg(struct gendi= sk *disk) } =20 extern void del_gendisk(struct gendisk *gp); +extern struct block_device *bdget_disk_sector(struct gendisk *disk, sect= or_t sector); =20 void set_disk_ro(struct gendisk *disk, bool read_only); =20 --=20 2.32.0