From mboxrd@z Thu Jan 1 00:00:00 1970 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 A72D63B8BD9; Tue, 7 Apr 2026 14:05:57 +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=1775570758; cv=none; b=WL6Xu4JIqgto0oEB1gczVghowKdtoVQ+gIUQTH0truiPiGzFC3INctVopx9RyKBodGHR2ya+EEHPSALqj6+CXIOwr20NUDsA3SwE2tWSWm2UTvA6HVcNTSjgHjz+JTPpMLihRz7nHCCIfzoZ7wpDTSCfxSVgW7r3341Hmc5aFlc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775570758; c=relaxed/simple; bh=6hFHCh9X0AJ66Uw7e3ZKMIm2CErL1hWGIOG4naQ3k3w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hDp/k8NDXJmTEeUSc5P9+efhL8hHvkwTBFybPn4HgoJnAlh5MtgH8iyVg5eJmcu0jIhBygCYUWgfRjTJLfrm5HiEFHTkbPslmXb6lh94H2afZfZc/ZjifMEcrIrujfdNsUb+58MzODx5t9XUa2Z4y22SEeXqTHg/Fu3qQCaqflg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (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=Fsme/I1z; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (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="Fsme/I1z" 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=Gw9usk+F1GQAte9rxiRiChyPVZXrpJZa7XBAVxnd/v0=; b=Fsme/I1zLzdqL37tXAM2Sbg39+ +DUTWzz7KWEBcskqiF0laibLKAChIw316lWQidc+KJP0wynFlhLxCeOK72eqPhOX8s1Pgij9kWtku Z4lREQj+ObpvjDUwyJwLSEsKjEm+EYu2/nFtao+DotEwn1Y1FywD1ndhSAYNkzPX20X7Rj5dEmhX0 Qw5IWT6ATi7dx7kPD9+IECfABXfxr9AtvoC17ZLNc9clyhcqcKMdxUbqdkflLHc7d7Ko8EluYb3wt xFyjfQhZTIcJDdDg8B2A5ih0mW0mbzmeNk03tpPJNAg2s+LYWQXBS+yFXnEcW1BATkfZhgPaLwrTY alzfwtig==; Received: from 2a02-8389-2341-5b80-d601-7564-c2e0-491c.cable.dynamic.v6.surfer.at ([2a02:8389:2341:5b80:d601:7564:c2e0:491c] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1wA740-00000006Ytx-3Nff; Tue, 07 Apr 2026 14:05:57 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Carlos Maiolino , Bart Van Assche , Damien Le Moal , linux-block@vger.kernel.org, linux-xfs@vger.kernel.org Subject: [PATCH 3/5] block: factor out a bio_await helper Date: Tue, 7 Apr 2026 16:05:26 +0200 Message-ID: <20260407140538.633364-4-hch@lst.de> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260407140538.633364-1-hch@lst.de> References: <20260407140538.633364-1-hch@lst.de> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Add a new helper to wait for a bio and anything chained off it to complete synchronously after submitting it. This factors common code out of submit_bio_wait and bio_await_chain and will also be useful for file system code and thus is exported. Note that this will now set REQ_SYNC also for the bio_await case for consistency. Nothing should look at the flag in the end_io handler, but if something does having the flag set makes more sense. Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal --- block/bio.c | 53 +++++++++++++++++++++++++++++++-------------- include/linux/bio.h | 2 ++ 2 files changed, 39 insertions(+), 16 deletions(-) diff --git a/block/bio.c b/block/bio.c index 434e41182c05..61d65c544bcc 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1468,17 +1468,20 @@ static void bio_wait_end_io(struct bio *bio) } /** - * submit_bio_wait - submit a bio, and wait until it completes - * @bio: The &struct bio which describes the I/O + * bio_await - call a function on a bio, and wait until it completes + * @bio: the bio which describes the I/O + * @submit: function called to submit the bio + * @priv: private data passed to @submit * - * Simple wrapper around submit_bio(). Returns 0 on success, or the error from - * bio_endio() on failure. + * Wait for the bio as well as any bio chained off it after executing the + * passed in callback @submit. The wait for the bio is set up before calling + * @submit to ensure that the completion is captured. If @submit is %NULL, + * submit_bio() is used instead to submit the bio. * - * WARNING: Unlike to how submit_bio() is usually used, this function does not - * result in bio reference to be consumed. The caller must drop the reference - * on his own. + * Note: this overrides the bi_private and bi_end_io fields in the bio. */ -int submit_bio_wait(struct bio *bio) +void bio_await(struct bio *bio, void *priv, + void (*submit)(struct bio *bio, void *priv)) { DECLARE_COMPLETION_ONSTACK_MAP(done, bio->bi_bdev->bd_disk->lockdep_map); @@ -1486,13 +1489,37 @@ int submit_bio_wait(struct bio *bio) bio->bi_private = &done; bio->bi_end_io = bio_wait_end_io; bio->bi_opf |= REQ_SYNC; - submit_bio(bio); + if (submit) + submit(bio, priv); + else + submit_bio(bio); blk_wait_io(&done); +} +EXPORT_SYMBOL_GPL(bio_await); +/** + * submit_bio_wait - submit a bio, and wait until it completes + * @bio: The &struct bio which describes the I/O + * + * Simple wrapper around submit_bio(). Returns 0 on success, or the error from + * bio_endio() on failure. + * + * WARNING: Unlike to how submit_bio() is usually used, this function does not + * result in bio reference to be consumed. The caller must drop the reference + * on his own. + */ +int submit_bio_wait(struct bio *bio) +{ + bio_await(bio, NULL, NULL); return blk_status_to_errno(bio->bi_status); } EXPORT_SYMBOL(submit_bio_wait); +static void bio_endio_cb(struct bio *bio, void *priv) +{ + bio_endio(bio); +} + /** * bdev_rw_virt - synchronously read into / write from kernel mapping * @bdev: block device to access @@ -1528,13 +1555,7 @@ EXPORT_SYMBOL_GPL(bdev_rw_virt); */ void bio_await_chain(struct bio *bio) { - DECLARE_COMPLETION_ONSTACK_MAP(done, - bio->bi_bdev->bd_disk->lockdep_map); - - bio->bi_private = &done; - bio->bi_end_io = bio_wait_end_io; - bio_endio(bio); - blk_wait_io(&done); + bio_await(bio, NULL, bio_endio_cb); bio_put(bio); } diff --git a/include/linux/bio.h b/include/linux/bio.h index 984844d2870b..97d747320b35 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -432,6 +432,8 @@ extern void bio_uninit(struct bio *); void bio_reset(struct bio *bio, struct block_device *bdev, blk_opf_t opf); void bio_reuse(struct bio *bio, blk_opf_t opf); void bio_chain(struct bio *, struct bio *); +void bio_await(struct bio *bio, void *priv, + void (*submit)(struct bio *bio, void *priv)); int __must_check bio_add_page(struct bio *bio, struct page *page, unsigned len, unsigned off); -- 2.47.3