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 7B0A62DC323; Wed, 18 Feb 2026 06:13:20 +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=1771395201; cv=none; b=h5p0hBtV/v/XYl0VgbtdBn7KY613W8Mevx/XbYId7kLNKI2Ivm0Ee8/DkKX0OXadPsnFoYIshG1h+3l9VPsLf9+IpELRWaDcu7SibGrF4wsKJ66nR9THL7afGX71gcEi41FuegbmnkJhow/t/PP/gEnIh5jYw1FGlTVrdN//I1E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771395201; c=relaxed/simple; bh=8ZibG+4U6DuxihapOGY84tC2eOAfVtSmkxmEGHbr++U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SjS+uh+Vwc+X8oEd7ixQkGFOQO7NhRbj4u6QGQl0GRtCGErjD75ewowA8tK9IeIPVVXwiJJr+Up1OwEN0ZH8PkzrjNXATV80/faCfYNBuEMrixmZDdXRxplVxa2D46Io7dCiqmgKOionh9V30WHMBcYfSDah5DL4yigDJeU+DQA= 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=nNR8NwLL; 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="nNR8NwLL" 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=O3D5/XbomMc7LHONrUioNsAi8fHrTTC0UGUxIOdIs9Q=; b=nNR8NwLLDq2k1DIS0M/z57vROv MYJ5BtYg5m0RSjU8Al1ipsOSr2b6sdgHP3/wsygrJAlhQXWD/OUY9asmS+mphgQcVN2ECXCVvny7w RnuDtDyCTGGv2733BWc8Qk9BBAS5OBncVdhwUbtDUcHA01ox0SEebMCe1JM2p4w/Dj/FN0j86tSBz oNGTYRDMxo8ZhoFVquSKklfDLEsLwlo/nf1H0F8gPGmnmbVkvl1rztmpwR/JYwVENhfg4ghluCBRs 8V0VS+SO+IzqHM75sqgoily+WpmAyTVrb341iCVItS+S7q+JKNton4WsZjR46Glah5fBA7gFlzx7i 9g924vHQ==; Received: from [2001:4bb8:2dc:9863:1842:9381:9c0f:de32] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vsaoJ-00000009LSM-0PW4; Wed, 18 Feb 2026 06:13:19 +0000 From: Christoph Hellwig To: Jens Axboe , Christian Brauner Cc: "Darrick J. Wong" , Carlos Maiolino , "Martin K. Petersen" , Anuj Gupta , Kanchan Joshi , linux-block@vger.kernel.org, nvdimm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org Subject: [PATCH 07/15] block: pass a maxlen argument to bio_iov_iter_bounce Date: Wed, 18 Feb 2026 07:12:01 +0100 Message-ID: <20260218061238.3317841-8-hch@lst.de> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260218061238.3317841-1-hch@lst.de> References: <20260218061238.3317841-1-hch@lst.de> Precedence: bulk X-Mailing-List: linux-fsdevel@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 Allow the file system to limit the size processed in a single bounce operation. This is needed when generating integrity data so that the size of a single integrity segment can't overflow. Signed-off-by: Christoph Hellwig Reviewed-by: Anuj Gupta Reviewed-by: Martin K. Petersen Reviewed-by: "Darrick J. Wong" Tested-by: Anuj Gupta --- block/bio.c | 17 ++++++++++------- fs/iomap/direct-io.c | 2 +- include/linux/bio.h | 2 +- 3 files changed, 12 insertions(+), 9 deletions(-) diff --git a/block/bio.c b/block/bio.c index 8203bb7455a9..1b880d621399 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1327,9 +1327,10 @@ static void bio_free_folios(struct bio *bio) } } -static int bio_iov_iter_bounce_write(struct bio *bio, struct iov_iter *iter) +static int bio_iov_iter_bounce_write(struct bio *bio, struct iov_iter *iter, + size_t maxlen) { - size_t total_len = iov_iter_count(iter); + size_t total_len = min(maxlen, iov_iter_count(iter)); if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED))) return -EINVAL; @@ -1367,9 +1368,10 @@ static int bio_iov_iter_bounce_write(struct bio *bio, struct iov_iter *iter) return 0; } -static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter) +static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter, + size_t maxlen) { - size_t len = min(iov_iter_count(iter), SZ_1M); + size_t len = min3(iov_iter_count(iter), maxlen, SZ_1M); struct folio *folio; folio = folio_alloc_greedy(GFP_KERNEL, &len); @@ -1408,6 +1410,7 @@ static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter) * bio_iov_iter_bounce - bounce buffer data from an iter into a bio * @bio: bio to send * @iter: iter to read from / write into + * @maxlen: maximum size to bounce * * Helper for direct I/O implementations that need to bounce buffer because * we need to checksum the data or perform other operations that require @@ -1415,11 +1418,11 @@ static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter) * copies the data into it. Needs to be paired with bio_iov_iter_unbounce() * called on completion. */ -int bio_iov_iter_bounce(struct bio *bio, struct iov_iter *iter) +int bio_iov_iter_bounce(struct bio *bio, struct iov_iter *iter, size_t maxlen) { if (op_is_write(bio_op(bio))) - return bio_iov_iter_bounce_write(bio, iter); - return bio_iov_iter_bounce_read(bio, iter); + return bio_iov_iter_bounce_write(bio, iter, maxlen); + return bio_iov_iter_bounce_read(bio, iter, maxlen); } static void bvec_unpin(struct bio_vec *bv, bool mark_dirty) diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 8c1fd7573aee..2ad7c70a4ccb 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -338,7 +338,7 @@ static ssize_t iomap_dio_bio_iter_one(struct iomap_iter *iter, bio->bi_end_io = iomap_dio_bio_end_io; if (dio->flags & IOMAP_DIO_BOUNCE) - ret = bio_iov_iter_bounce(bio, dio->submit.iter); + ret = bio_iov_iter_bounce(bio, dio->submit.iter, BIO_MAX_SIZE); else ret = bio_iov_iter_get_pages(bio, dio->submit.iter, alignment - 1); diff --git a/include/linux/bio.h b/include/linux/bio.h index 36a3f2275ecd..9693a0d6fefe 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -474,7 +474,7 @@ void __bio_release_pages(struct bio *bio, bool mark_dirty); extern void bio_set_pages_dirty(struct bio *bio); extern void bio_check_pages_dirty(struct bio *bio); -int bio_iov_iter_bounce(struct bio *bio, struct iov_iter *iter); +int bio_iov_iter_bounce(struct bio *bio, struct iov_iter *iter, size_t maxlen); void bio_iov_iter_unbounce(struct bio *bio, bool is_error, bool mark_dirty); extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter, -- 2.47.3