From patchwork Sun Apr 28 05:16:20 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Al Viro X-Patchwork-Id: 13645853 Received: from zeniv.linux.org.uk (zeniv.linux.org.uk [62.89.141.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BBC4A321D; Sun, 28 Apr 2024 05:16:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.89.141.173 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714281384; cv=none; b=klBXkzAeAEdEdwLTVqq6VXnnfRrbMias+sD0BzdS07Ejo4V+g1BNN/GY9uNwEyOl/TOQCBGRhbwoTcvTdZ8EUXY6+bj3bzukG430Pj7zYKfTCgS+SMPkaji8enN/Ax9m01OL/7S3ySESap6EektLFAyDAYTsvBdLR8TrD2x9hOU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714281384; c=relaxed/simple; bh=q0RAssYWsvGYCQEhxffMOxjxrhMhIBZbvWOAYDWsB+c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=YVafpBfNnOr7Cs/BRkm7/oMdKXC3mCkV49sTSVxoCD6j5aT2vQIKfHPVpZIANCxtpgfX19/ywpbi5e/3iFWs374GLd2tO2qT3InQuycqSFOKvSAfYrURv2LVz/D7q3TkSuEzORfuiFmkrQhwEDypgt47y2LrgrWWoPsvbn3WwLQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk; spf=none smtp.mailfrom=ftp.linux.org.uk; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b=hMrBQnLU; arc=none smtp.client-ip=62.89.141.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=ftp.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b="hMrBQnLU" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=linux.org.uk; s=zeniv-20220401; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=pa27QOZhgTYyjdTX6K9oFf7IjSK8d/+qozIJWisXWV0=; b=hMrBQnLU5MFUWkpUtzCSjw9U+F vze8lDtnckLgJuXdAWEj+ZJrABZ6L5a07rBHGDeVPE+ANvU6p5dVZ0ocO2iHShvVtI6ThIXtKUbgp ZzajvdfPtOxvuBC6wtIZ+Oe+LuswR3kgFB8ByIlZSSK2nR0FHauDA3jdqmNm1HEH1ol0GNnumRTWy zTVUFSj6ANLsvEKYiLGBxTM9GJqcL5S4GCnivwLjYFneSbf1Kh66TpQE8pCwk5dXVqKpIwVZVvIIY 3InOlQA8XdXX/eVPZwyuPXygPtGMHXnWQlqeG0coQO7oAnaU62ZouVCITs5PS0qQdOdHx9CCRZRAS NfkmFxCA==; Received: from viro by zeniv.linux.org.uk with local (Exim 4.96 #2 (Red Hat Linux)) id 1s0wtg-006VIB-3B; Sun, 28 Apr 2024 05:16:21 +0000 Date: Sun, 28 Apr 2024 06:16:20 +0100 From: Al Viro To: linux-fsdevel@vger.kernel.org Cc: Yu Kuai , linux-block@vger.kernel.org, Christian Brauner , Christoph Hellwig , Jens Axboe Subject: [PATCH 3/8] bdev: infrastructure for flags Message-ID: <20240428051620.GC1549798@ZenIV> References: <20240428051232.GU2118490@ZenIV> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20240428051232.GU2118490@ZenIV> Sender: Al Viro Replace bd_partno with a 32bit field (__bd_flags). The lower 8 bits contain the partition number, the upper 24 are for flags. Helpers: bdev_{test,set,clear}_flag(bdev, flag), where flag numbers are zero-based. Use cmpxchg() to set/clear - all architectures support it for u32. NOTE: this commit does not actuall move any flags over there - they are still bool fields. As the result, it shifts the fields wrt cacheline boundaries; that's going to be restored once the first 3 flags are dealt with. Signed-off-by: Al Viro --- block/bdev.c | 2 +- include/linux/blk_types.h | 2 +- include/linux/blkdev.h | 33 ++++++++++++++++++++++++++++++++- 3 files changed, 34 insertions(+), 3 deletions(-) diff --git a/block/bdev.c b/block/bdev.c index 7a5f611c3d2e..0c55f7abaac3 100644 --- a/block/bdev.c +++ b/block/bdev.c @@ -411,7 +411,7 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno) mutex_init(&bdev->bd_fsfreeze_mutex); spin_lock_init(&bdev->bd_size_lock); mutex_init(&bdev->bd_holder_lock); - bdev->bd_partno = partno; + bdev->__bd_flags = partno; bdev->bd_inode = inode; bdev->bd_queue = disk->queue; if (partno) diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index cb1526ec44b5..274f7eb4138f 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -45,8 +45,8 @@ struct block_device { struct request_queue * bd_queue; struct disk_stats __percpu *bd_stats; unsigned long bd_stamp; + u32 __bd_flags; // partition number + flags bool bd_read_only; /* read-only policy */ - u8 bd_partno; bool bd_write_holder; bool bd_has_submit_bio; dev_t bd_dev; diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 32549d675955..b9dbfb811533 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -722,7 +722,38 @@ void disk_uevent(struct gendisk *disk, enum kobject_action action); static inline u8 bdev_partno(const struct block_device *bdev) { - return bdev->bd_partno; + return bdev->__bd_flags & 0xff; +} + +static inline bool bdev_test_flag(const struct block_device *bdev, int flag) +{ + return bdev->__bd_flags & (1 << (flag + 8)); +} + +static inline void bdev_set_flag(struct block_device *bdev, int flag) +{ + u32 v = bdev->__bd_flags; + + for (;;) { + u32 w = cmpxchg(&bdev->__bd_flags, v, v | (1 << (flag + 8))); + + if (v == w) + return; + v = w; + } +} + +static inline void bdev_clear_flag(struct block_device *bdev, int flag) +{ + u32 v = bdev->__bd_flags; + + for (;;) { + u32 w = cmpxchg(&bdev->__bd_flags, v, v & ~(1 << (flag + 8))); + + if (v == w) + return; + v = w; + } } static inline int get_disk_ro(struct gendisk *disk)