From:   Christoph Hellwig <hch@lst.de>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     Ilya Dryomov <idryomov@gmail.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>,
        Minchan Kim <minchan@kernel.org>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        Keith Busch <kbusch@kernel.org>,
        Sagi Grimberg <sagi@grimberg.me>,
        Chaitanya Kulkarni <kch@nvidia.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        David Howells <dhowells@redhat.com>,
        Marc Dionne <marc.dionne@auristor.com>,
        Xiubo Li <xiubli@redhat.com>, Steve French <sfrench@samba.org>,
        Trond Myklebust <trond.myklebust@hammerspace.com>,
        Anna Schumaker <anna@kernel.org>,
        Mike Marshall <hubcap@omnibond.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Chuck Lever <chuck.lever@oracle.com>,
        linux-block@vger.kernel.org, ceph-devel@vger.kernel.org,
        virtualization@lists.linux-foundation.org,
        linux-nvme@lists.infradead.org, linux-scsi@vger.kernel.org,
        target-devel@vger.kernel.org, kvm@vger.kernel.org,
        netdev@vger.kernel.org, linux-afs@lists.infradead.org,
        linux-cifs@vger.kernel.org, samba-technical@lists.samba.org,
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        devel@lists.orangefs.org, io-uring@vger.kernel.org,
        linux-mm@kvack.org
Subject: [PATCH 01/23] block: factor out a bvec_set_page helper
Date:   Mon, 30 Jan 2023 10:21:35 +0100
Message-Id: <20230130092157.1759539-2-hch@lst.de>
In-Reply-To: <20230130092157.1759539-1-hch@lst.de>
References: <20230130092157.1759539-1-hch@lst.de>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Add a helper to initialize a bvec based of a page pointer.  This will help
removing various open code bvec initializations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 block/bio-integrity.c |  7 +------
 block/bio.c           | 12 ++----------
 include/linux/bvec.h  | 15 +++++++++++++++
 3 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 3f5685c00e360b..a3776064c52a16 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -124,23 +124,18 @@ int bio_integrity_add_page(struct bio *bio, struct page *page,
 			   unsigned int len, unsigned int offset)
 {
 	struct bio_integrity_payload *bip = bio_integrity(bio);
-	struct bio_vec *iv;
 
 	if (bip->bip_vcnt >= bip->bip_max_vcnt) {
 		printk(KERN_ERR "%s: bip_vec full\n", __func__);
 		return 0;
 	}
 
-	iv = bip->bip_vec + bip->bip_vcnt;
-
 	if (bip->bip_vcnt &&
 	    bvec_gap_to_prev(&bdev_get_queue(bio->bi_bdev)->limits,
 			     &bip->bip_vec[bip->bip_vcnt - 1], offset))
 		return 0;
 
-	iv->bv_page = page;
-	iv->bv_len = len;
-	iv->bv_offset = offset;
+	bvec_set_page(&bip->bip_vec[bip->bip_vcnt], page, len, offset);
 	bip->bip_vcnt++;
 
 	return len;
diff --git a/block/bio.c b/block/bio.c
index d7fbc7adfc50aa..71e411a0c12950 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1029,10 +1029,7 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio,
 	if (bio->bi_vcnt >= queue_max_segments(q))
 		return 0;
 
-	bvec = &bio->bi_io_vec[bio->bi_vcnt];
-	bvec->bv_page = page;
-	bvec->bv_len = len;
-	bvec->bv_offset = offset;
+	bvec_set_page(&bio->bi_io_vec[bio->bi_vcnt], page, len, offset);
 	bio->bi_vcnt++;
 	bio->bi_iter.bi_size += len;
 	return len;
@@ -1108,15 +1105,10 @@ EXPORT_SYMBOL_GPL(bio_add_zone_append_page);
 void __bio_add_page(struct bio *bio, struct page *page,
 		unsigned int len, unsigned int off)
 {
-	struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt];
-
 	WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
 	WARN_ON_ONCE(bio_full(bio, len));
 
-	bv->bv_page = page;
-	bv->bv_offset = off;
-	bv->bv_len = len;
-
+	bvec_set_page(&bio->bi_io_vec[bio->bi_vcnt], page, len, off);
 	bio->bi_iter.bi_size += len;
 	bio->bi_vcnt++;
 }
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index 35c25dff651a5e..9e3dac51eb26b6 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -35,6 +35,21 @@ struct bio_vec {
 	unsigned int	bv_offset;
 };
 
+/**
+ * bvec_set_page - initialize a bvec based off a struct page
+ * @bv:		bvec to initialize
+ * @page:	page the bvec should point to
+ * @len:	length of the bvec
+ * @offset:	offset into the page
+ */
+static inline void bvec_set_page(struct bio_vec *bv, struct page *page,
+		unsigned int len, unsigned int offset)
+{
+	bv->bv_page = page;
+	bv->bv_len = len;
+	bv->bv_offset = offset;
+}
+
 struct bvec_iter {
 	sector_t		bi_sector;	/* device address in 512 byte
 						   sectors */
-- 
2.39.0