From patchwork Wed Aug 2 15:41:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 13338411 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DDD92C04FDF for ; Wed, 2 Aug 2023 15:41:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233956AbjHBPl4 (ORCPT ); Wed, 2 Aug 2023 11:41:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34548 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234311AbjHBPlu (ORCPT ); Wed, 2 Aug 2023 11:41:50 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A9F75EE; Wed, 2 Aug 2023 08:41:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=XnpsdZtpyIJaScQ5NhvJitYDj8RzkQAdmUbC7tO240g=; b=moDSih/fwZ/ce0Ve1LXdFc0m8L iSvuVeExi91q1m3s2Iou36pDkNYIkeUEUD2rJAGrBOpXtvAFCX9sxuMGF3gzFuSkPGBwBV/cburHF E75407Qm9yEWNVapmncdD+w/8lxmK7gukVYRR/DY9xsBMrZcd+AJJ2QyNw9LxSMnYXuqAiQ/q+F1f 9DM2cn7JLLYY+gl4CqGTevvJB1O9CIjNJAbIJ4pNo9eV0ruEai++QSPcY+gYL7weOo7vwc0o7B5c+ Yn6vpPxgtUlcTvjn6HiHjqPK2RW7keOHHYnX5/iBs/MfeMw9E6cywXBAMgQZbRawpS5kmTrhkIeyU M/w93iLw==; Received: from 2a02-8389-2341-5b80-39d3-4735-9a3c-88d8.cable.dynamic.v6.surfer.at ([2a02:8389:2341:5b80:39d3:4735:9a3c:88d8] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1qRDyn-005GEZ-2D; Wed, 02 Aug 2023 15:41:42 +0000 From: Christoph Hellwig To: Al Viro , Christian Brauner Cc: Jan Kara , Chris Mason , Josef Bacik , David Sterba , "Theodore Ts'o" , Andreas Dilger , Jaegeuk Kim , Chao Yu , Ryusuke Konishi , "Darrick J. Wong" , Jens Axboe , linux-btrfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-nilfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-block@vger.kernel.org Subject: [PATCH 02/12] nilfs2: use setup_bdev_super to de-duplicate the mount code Date: Wed, 2 Aug 2023 17:41:21 +0200 Message-Id: <20230802154131.2221419-3-hch@lst.de> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230802154131.2221419-1-hch@lst.de> References: <20230802154131.2221419-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Use the generic setup_bdev_super helper to open the main block device and do various bits of superblock setup instead of duplicating the logic. This includes moving to the new scheme implemented in common code that only opens the block device after the superblock has allocated. It does not yet convert nilfs2 to the new mount API, but doing so will become a bit simpler after this first step. Signed-off-by: Christoph Hellwig Acked-by: Ryusuke Konishi --- fs/nilfs2/super.c | 81 ++++++++++++++++++----------------------------- 1 file changed, 30 insertions(+), 51 deletions(-) diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c index 0ef8c71bde8e5f..a5d1fa4e7552f6 100644 --- a/fs/nilfs2/super.c +++ b/fs/nilfs2/super.c @@ -35,6 +35,7 @@ #include #include #include +#include #include "nilfs.h" #include "export.h" #include "mdt.h" @@ -1216,7 +1217,6 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data) } struct nilfs_super_data { - struct block_device *bdev; __u64 cno; int flags; }; @@ -1283,64 +1283,49 @@ static int nilfs_identify(char *data, struct nilfs_super_data *sd) static int nilfs_set_bdev_super(struct super_block *s, void *data) { - s->s_bdev = data; - s->s_dev = s->s_bdev->bd_dev; + s->s_dev = *(dev_t *)data; return 0; } static int nilfs_test_bdev_super(struct super_block *s, void *data) { - return (void *)s->s_bdev == data; + return !(s->s_iflags & SB_I_RETIRED) && s->s_dev == *(dev_t *)data; } static struct dentry * nilfs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { - struct nilfs_super_data sd; + struct nilfs_super_data sd = { .flags = flags }; struct super_block *s; - struct dentry *root_dentry; - int err, s_new = false; + dev_t dev; + int err; - sd.bdev = blkdev_get_by_path(dev_name, sb_open_mode(flags), fs_type, - NULL); - if (IS_ERR(sd.bdev)) - return ERR_CAST(sd.bdev); + if (nilfs_identify(data, &sd)) + return ERR_PTR(-EINVAL); - sd.cno = 0; - sd.flags = flags; - if (nilfs_identify((char *)data, &sd)) { - err = -EINVAL; - goto failed; - } + err = lookup_bdev(dev_name, &dev); + if (err) + return ERR_PTR(err); - /* - * once the super is inserted into the list by sget, s_umount - * will protect the lockfs code from trying to start a snapshot - * while we are mounting - */ - mutex_lock(&sd.bdev->bd_fsfreeze_mutex); - if (sd.bdev->bd_fsfreeze_count > 0) { - mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); - err = -EBUSY; - goto failed; - } s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, flags, - sd.bdev); - mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); - if (IS_ERR(s)) { - err = PTR_ERR(s); - goto failed; - } + &dev); + if (IS_ERR(s)) + return ERR_CAST(s); if (!s->s_root) { - s_new = true; - - /* New superblock instance created */ - snprintf(s->s_id, sizeof(s->s_id), "%pg", sd.bdev); - sb_set_blocksize(s, block_size(sd.bdev)); - - err = nilfs_fill_super(s, data, flags & SB_SILENT ? 1 : 0); + /* + * We drop s_umount here because we need to open the bdev and + * bdev->open_mutex ranks above s_umount (blkdev_put() -> + * __invalidate_device()). It is safe because we have active sb + * reference and SB_BORN is not set yet. + */ + up_write(&s->s_umount); + err = setup_bdev_super(s, flags, NULL); + down_write(&s->s_umount); + if (!err) + err = nilfs_fill_super(s, data, + flags & SB_SILENT ? 1 : 0); if (err) goto failed_super; @@ -1366,24 +1351,18 @@ nilfs_mount(struct file_system_type *fs_type, int flags, } if (sd.cno) { + struct dentry *root_dentry; + err = nilfs_attach_snapshot(s, sd.cno, &root_dentry); if (err) goto failed_super; - } else { - root_dentry = dget(s->s_root); + return root_dentry; } - if (!s_new) - blkdev_put(sd.bdev, fs_type); - - return root_dentry; + return dget(s->s_root); failed_super: deactivate_locked_super(s); - - failed: - if (!s_new) - blkdev_put(sd.bdev, fs_type); return ERR_PTR(err); }