From patchwork Fri Aug 11 10:08:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 13350423 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 92E07C001DB for ; Fri, 11 Aug 2023 10:09:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235564AbjHKKJW (ORCPT ); Fri, 11 Aug 2023 06:09:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49800 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235539AbjHKKI7 (ORCPT ); Fri, 11 Aug 2023 06:08:59 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9CF6530D6; Fri, 11 Aug 2023 03:08:46 -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=r6gDfPhaoM7J2iRzTUUAmIosaWN5Ed601e9pLnuJfEs=; b=hNapXvvsvvDvwITKXZVGSZpgwU +YuvGQVrbtALKKwhEmdUw594Ky8bDr2cjaMhvr9qb/ab5q+T5wKfH/D9a/3VO+BhBq9d2am/FVHNL oxCs1BCWMRerkWr0GPYQhvdLKmp64gYyOaCtS8AS8KdbAIOHTItUFBCaGPKDCB+v3zJDYwbryzXP+ 357veeDbEeDL8ZRhha8cEyyd2QmC64GLcYxJ1KiHUog0/NbqgmIBPKi9qOuumVITMM7J5ShAAIKyU N88uYpPY1geqwBvYovpFWWNXq1qfgM5VDdAfNx9LRRzuLvfReG0JJSfZl4nq1FoKfhdAH7ew7ncHB e7uQRRAQ==; Received: from [88.128.92.63] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1qUP4O-00A5Zk-2H; Fri, 11 Aug 2023 10:08:37 +0000 From: Christoph Hellwig To: Al Viro , Christian Brauner Cc: Jens Axboe , Denis Efremov , Josef Bacik , Stefan Haberland , Jan Hoeppner , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , "Darrick J . Wong" , Chris Mason , David Sterba , linux-block@vger.kernel.org, nbd@other.debian.org, linux-s390@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH 02/17] btrfs: always open the device read-only in btrfs_scan_one_device Date: Fri, 11 Aug 2023 12:08:13 +0200 Message-Id: <20230811100828.1897174-3-hch@lst.de> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230811100828.1897174-1-hch@lst.de> References: <20230811100828.1897174-1-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 btrfs_scan_one_device opens the block device only to read the super block. Instead of passing a blk_mode_t argument to sometimes open it for writing, just hard code BLK_OPEN_READ as it will never write to the device or hand the block_device out to someone else. Signed-off-by: Christoph Hellwig Reviewed-by: Christian Brauner --- fs/btrfs/super.c | 15 +++++++-------- fs/btrfs/volumes.c | 4 ++-- fs/btrfs/volumes.h | 2 +- 3 files changed, 10 insertions(+), 11 deletions(-) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index f1dd172d8d5bd7..b318bddefd5236 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -849,7 +849,7 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options, * All other options will be parsed on much later in the mount process and * only when we need to allocate a new super block. */ -static int btrfs_parse_device_options(const char *options, blk_mode_t flags) +static int btrfs_parse_device_options(const char *options) { substring_t args[MAX_OPT_ARGS]; char *device_name, *opts, *orig, *p; @@ -883,7 +883,7 @@ static int btrfs_parse_device_options(const char *options, blk_mode_t flags) error = -ENOMEM; goto out; } - device = btrfs_scan_one_device(device_name, flags); + device = btrfs_scan_one_device(device_name); kfree(device_name); if (IS_ERR(device)) { error = PTR_ERR(device); @@ -1440,7 +1440,6 @@ static struct dentry *btrfs_mount_root(struct file_system_type *fs_type, struct btrfs_fs_devices *fs_devices = NULL; struct btrfs_fs_info *fs_info = NULL; void *new_sec_opts = NULL; - blk_mode_t mode = sb_open_mode(flags); int error = 0; if (data) { @@ -1472,13 +1471,13 @@ static struct dentry *btrfs_mount_root(struct file_system_type *fs_type, } mutex_lock(&uuid_mutex); - error = btrfs_parse_device_options(data, mode); + error = btrfs_parse_device_options(data); if (error) { mutex_unlock(&uuid_mutex); goto error_fs_info; } - device = btrfs_scan_one_device(device_name, mode); + device = btrfs_scan_one_device(device_name); if (IS_ERR(device)) { mutex_unlock(&uuid_mutex); error = PTR_ERR(device); @@ -1488,7 +1487,7 @@ static struct dentry *btrfs_mount_root(struct file_system_type *fs_type, fs_devices = device->fs_devices; fs_info->fs_devices = fs_devices; - error = btrfs_open_devices(fs_devices, mode, fs_type); + error = btrfs_open_devices(fs_devices, sb_open_mode(flags), fs_type); mutex_unlock(&uuid_mutex); if (error) goto error_fs_info; @@ -2190,7 +2189,7 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd, switch (cmd) { case BTRFS_IOC_SCAN_DEV: mutex_lock(&uuid_mutex); - device = btrfs_scan_one_device(vol->name, BLK_OPEN_READ); + device = btrfs_scan_one_device(vol->name); ret = PTR_ERR_OR_ZERO(device); mutex_unlock(&uuid_mutex); break; @@ -2204,7 +2203,7 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd, break; case BTRFS_IOC_DEVICES_READY: mutex_lock(&uuid_mutex); - device = btrfs_scan_one_device(vol->name, BLK_OPEN_READ); + device = btrfs_scan_one_device(vol->name); if (IS_ERR(device)) { mutex_unlock(&uuid_mutex); ret = PTR_ERR(device); diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 73f9ea7672dbda..8246578c70f55b 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1356,7 +1356,7 @@ int btrfs_forget_devices(dev_t devt) * and we are not allowed to call set_blocksize during the scan. The superblock * is read via pagecache */ -struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags) +struct btrfs_device *btrfs_scan_one_device(const char *path) { struct btrfs_super_block *disk_super; bool new_device_added = false; @@ -1384,7 +1384,7 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags) * values temporarily, as the device paths of the fsid are the only * required information for assembling the volume. */ - bdev = blkdev_get_by_path(path, flags, NULL, NULL); + bdev = blkdev_get_by_path(path, BLK_OPEN_READ, NULL, NULL); if (IS_ERR(bdev)) return ERR_CAST(bdev); diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index b8c51f16ba867f..824161c6dd063e 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -611,7 +611,7 @@ struct btrfs_block_group *btrfs_create_chunk(struct btrfs_trans_handle *trans, void btrfs_mapping_tree_free(struct extent_map_tree *tree); int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, blk_mode_t flags, void *holder); -struct btrfs_device *btrfs_scan_one_device(const char *path, blk_mode_t flags); +struct btrfs_device *btrfs_scan_one_device(const char *path); int btrfs_forget_devices(dev_t devt); void btrfs_close_devices(struct btrfs_fs_devices *fs_devices); void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices);