From patchwork Mon Feb 26 10:30:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 13571880 X-Patchwork-Delegate: snitzer@redhat.com Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 76D211DFD1; Mon, 26 Feb 2024 10:31:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708943482; cv=none; b=c5itlDWBbZpSy2LZwkt5vVxJrXCyPu6wfAA8oU1Pov3MnXrr6z7LA7LNAwtWdWpiFQbcR1CiZ6DGvVzHsik3ZEa1CKtMQiupAj8uofVW4B0aIW0MJP5qnyrNqbx6Wxz7caExa/mk8ol7htOGIiPt9JoH8YIpiDe8eTk/rLjU7FA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708943482; c=relaxed/simple; bh=AsrYHsG7r6XadTI3QCTSg4hezSD4FYHHHuLdbXXQ+TA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=dyYqgoI50gGxpt4GYt1mdyvW7/aqkp06+4OzdZZLa3okwAIEFlMKSqxz9VgcuCaDTWR5BWapZ4SH9EO66e4w3TQVscDjIFm1rV/GZUPYnWHmIf0boqGpEmuy+eECHgPj4cpp7aYy4uBV1n0Vii9gIHHMxkNQ0GlM3MznO5YpR6E= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=RKmXtcsx; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="RKmXtcsx" 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=0KKDb4GuesD/jXOw/b5195T9S3k6Ul/k1CdB+JFeMjg=; b=RKmXtcsxAXaY0O7ggdOg000ZYN Nj7jdQhz8JZVwptX0zykKjDfqajQPE/rqkwz6mq+Tn19FkOnppynEbq0Wg3GWboeqqT+mnI/htPGB fYuAv9qRLcBKfEypQ1QgFukEJCgbMfDMa742lXE5cj1FNRi+VXGJY8HBlrUz/d0o14X8sZxVdNvVF uSyB8rPNwG9VbOh7G0N6VvcFRO16KtZ0J175dbeB6CHHGNYa6b62JhYg/xfr2HlYMFWv7VE5nZEX8 E17hNQ2juwG/swiN4ntsGK6qa4h5SgTz6h53/V9QLwwp8eTmBx581m7gIAv/E3pvq4zoJ8oOaIsy+ ZUU+mnlw==; Received: from 213-147-167-65.nat.highway.webapn.at ([213.147.167.65] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1reYGU-000000004zq-3IoV; Mon, 26 Feb 2024 10:31:20 +0000 From: Christoph Hellwig To: Jens Axboe , Mike Snitzer , Mikulas Patocka , Song Liu , Yu Kuai , Philipp Reisner , Lars Ellenberg , =?utf-8?q?Christoph_B=C3=B6hmwa?= =?utf-8?q?lder?= Cc: drbd-dev@lists.linbit.com, dm-devel@lists.linux.dev, linux-block@vger.kernel.org, linux-raid@vger.kernel.org Subject: [PATCH 12/16] drbd: refactor the backing dev max_segments calculation Date: Mon, 26 Feb 2024 11:30:00 +0100 Message-Id: <20240226103004.281412-13-hch@lst.de> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240226103004.281412-1-hch@lst.de> References: <20240226103004.281412-1-hch@lst.de> Precedence: bulk X-Mailing-List: dm-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Factor out a drbd_backing_dev_max_segments helper that checks the backing device limitation. Signed-off-by: Christoph Hellwig --- drivers/block/drbd/drbd_nl.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index 9135001a8e572d..0326b7322ceb48 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -1295,30 +1295,39 @@ static void fixup_discard_support(struct drbd_device *device, struct request_que } } +/* This is the workaround for "bio would need to, but cannot, be split" */ +static unsigned int drbd_backing_dev_max_segments(struct drbd_device *device) +{ + unsigned int max_segments; + + rcu_read_lock(); + max_segments = rcu_dereference(device->ldev->disk_conf)->max_bio_bvecs; + rcu_read_unlock(); + + if (!max_segments) + return BLK_MAX_SEGMENTS; + return max_segments; +} + static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backing_dev *bdev, unsigned int max_bio_size, struct o_qlim *o) { struct request_queue * const q = device->rq_queue; unsigned int max_hw_sectors = max_bio_size >> 9; - unsigned int max_segments = 0; + unsigned int max_segments = BLK_MAX_SEGMENTS; struct request_queue *b = NULL; - struct disk_conf *dc; if (bdev) { b = bdev->backing_bdev->bd_disk->queue; max_hw_sectors = min(queue_max_hw_sectors(b), max_bio_size >> 9); - rcu_read_lock(); - dc = rcu_dereference(device->ldev->disk_conf); - max_segments = dc->max_bio_bvecs; - rcu_read_unlock(); + max_segments = drbd_backing_dev_max_segments(device); blk_set_stacking_limits(&q->limits); } blk_queue_max_hw_sectors(q, max_hw_sectors); - /* This is the workaround for "bio would need to, but cannot, be split" */ - blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS); + blk_queue_max_segments(q, max_segments); blk_queue_segment_boundary(q, PAGE_SIZE-1); decide_on_discard_support(device, bdev);