From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 39F6FC19F2A for ; Tue, 26 Jul 2022 17:38:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229576AbiGZRib (ORCPT ); Tue, 26 Jul 2022 13:38:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33178 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239503AbiGZRi3 (ORCPT ); Tue, 26 Jul 2022 13:38:29 -0400 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE3062E9DA for ; Tue, 26 Jul 2022 10:38:27 -0700 (PDT) Received: from pps.filterd (m0109334.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 26QFWBBH010634 for ; Tue, 26 Jul 2022 10:38:27 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=wyQlYXUSk9g4uiRzXyUdO+frsHVF03nRChlrghL7lbQ=; b=SUaqRJtfBCby4ucNynjP1m/xojgFMlMgeK1MkAqYQ3fw/74tt2Qod2L+6KfjaCjVDBV5 D0zRJwMZEwvX1SvMGX7s9TXhAZxTw9k4pGgJi5hKVVUtXVZ6LRB/UNl9EOsOmBN8BNxf qQvaECuspcK2Mx9KK/W+cExQjvtTaaER/UA= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3hhxbwr9p8-3 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Tue, 26 Jul 2022 10:38:27 -0700 Received: from twshared30313.14.frc2.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::d) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.28; Tue, 26 Jul 2022 10:38:24 -0700 Received: by devbig007.nao1.facebook.com (Postfix, from userid 544533) id 6A7F7698E4AE; Tue, 26 Jul 2022 10:38:15 -0700 (PDT) From: Keith Busch To: , , , CC: , , Alexander Viro , Keith Busch Subject: [PATCH 3/5] block: add dma tag bio type Date: Tue, 26 Jul 2022 10:38:12 -0700 Message-ID: <20220726173814.2264573-4-kbusch@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220726173814.2264573-1-kbusch@fb.com> References: <20220726173814.2264573-1-kbusch@fb.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-GUID: l25mreEg8PTHWbDEmHcR6_lck66kZMgQ X-Proofpoint-ORIG-GUID: l25mreEg8PTHWbDEmHcR6_lck66kZMgQ X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-07-26_05,2022-07-26_01,2022-06-22_01 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org From: Keith Busch Premapped buffers don't require a generic bio_vec since these have already been dma mapped to the driver specific data structure. Repurpose the bi_io_vec with the driver specific tag as they are mutually exclusive, and provide all the setup and split helpers to support dma tags. In order to use this, a driver must implement the .dma_map() callback. If the driver provides this callback, then it must be aware that any given bio may be using a dma_tag instead of a bio_vec. Note, this isn't working with blk_integrity. Signed-off-by: Keith Busch --- block/bio.c | 25 ++++++++++++++++++++++++- block/blk-merge.c | 18 ++++++++++++++++++ include/linux/bio.h | 21 ++++++++++++--------- include/linux/blk-mq.h | 12 ++++++++++++ include/linux/blk_types.h | 6 +++++- 5 files changed, 71 insertions(+), 11 deletions(-) diff --git a/block/bio.c b/block/bio.c index ce3bc3578ac4..472bdc4fd419 100644 --- a/block/bio.c +++ b/block/bio.c @@ -229,7 +229,8 @@ static void bio_free(struct bio *bio) WARN_ON_ONCE(!bs); =20 bio_uninit(bio); - bvec_free(&bs->bvec_pool, bio->bi_io_vec, bio->bi_max_vecs); + if (!bio_flagged(bio, BIO_DMA_TAGGED)) + bvec_free(&bs->bvec_pool, bio->bi_io_vec, bio->bi_max_vecs); mempool_free(p - bs->front_pad, &bs->bio_pool); } =20 @@ -762,6 +763,8 @@ static int __bio_clone(struct bio *bio, struct bio *b= io_src, gfp_t gfp) bio_set_flag(bio, BIO_CLONED); if (bio_flagged(bio_src, BIO_THROTTLED)) bio_set_flag(bio, BIO_THROTTLED); + if (bio_flagged(bio_src, BIO_DMA_TAGGED)) + bio_set_flag(bio, BIO_DMA_TAGGED); bio->bi_ioprio =3D bio_src->bi_ioprio; bio->bi_iter =3D bio_src->bi_iter; =20 @@ -1151,6 +1154,21 @@ void bio_iov_bvec_set(struct bio *bio, struct iov_= iter *iter) bio_set_flag(bio, BIO_CLONED); } =20 +static void bio_iov_dma_tag_set(struct bio *bio, struct iov_iter *iter) +{ + size_t size =3D iov_iter_count(iter); + + bio->bi_vcnt =3D iter->nr_segs; + bio->bi_dma_tag =3D iter->dma_tag; + bio->bi_iter.bi_bvec_done =3D iter->iov_offset; + bio->bi_iter.bi_size =3D size; + bio->bi_opf |=3D REQ_NOMERGE; + bio_set_flag(bio, BIO_NO_PAGE_REF); + bio_set_flag(bio, BIO_DMA_TAGGED); + + iov_iter_advance(iter, bio->bi_iter.bi_size); +} + static int bio_iov_add_page(struct bio *bio, struct page *page, unsigned int len, unsigned int offset) { @@ -1287,6 +1305,11 @@ int bio_iov_iter_get_pages(struct bio *bio, struct= iov_iter *iter) return 0; } =20 + if (iov_iter_is_dma_tag(iter)) { + bio_iov_dma_tag_set(bio, iter); + return 0; + } + do { ret =3D __bio_iov_iter_get_pages(bio, iter); } while (!ret && iov_iter_count(iter) && !bio_full(bio, 0)); diff --git a/block/blk-merge.c b/block/blk-merge.c index 4c8a699754c9..240eae7666d4 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -276,6 +276,24 @@ static struct bio *blk_bio_segment_split(struct requ= est_queue *q, const unsigned max_bytes =3D get_max_io_size(q, bio) << 9; const unsigned max_segs =3D queue_max_segments(q); =20 + if (bio_flagged(bio, BIO_DMA_TAGGED)) { + int offset =3D offset_in_page(bio->bi_iter.bi_bvec_done); + + nsegs =3D ALIGN(bio->bi_iter.bi_size + offset, PAGE_SIZE) >> PAGE_SHIF= T; + if (bio->bi_iter.bi_size > max_bytes) { + bytes =3D max_bytes; + nsegs =3D (bytes + offset) >> PAGE_SHIFT; + } else if (nsegs > max_segs) { + nsegs =3D max_segs; + bytes =3D PAGE_SIZE * nsegs - offset; + } else { + *segs =3D nsegs; + return NULL; + } + + goto split; + } + bio_for_each_bvec(bv, bio, iter) { /* * If the queue doesn't support SG gaps and adding this diff --git a/include/linux/bio.h b/include/linux/bio.h index ca22b06700a9..649348bc03c2 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -61,11 +61,17 @@ static inline bool bio_has_data(struct bio *bio) return false; } =20 +static inline bool bio_flagged(const struct bio *bio, unsigned int bit) +{ + return (bio->bi_flags & (1U << bit)) !=3D 0; +} + static inline bool bio_no_advance_iter(const struct bio *bio) { return bio_op(bio) =3D=3D REQ_OP_DISCARD || bio_op(bio) =3D=3D REQ_OP_SECURE_ERASE || - bio_op(bio) =3D=3D REQ_OP_WRITE_ZEROES; + bio_op(bio) =3D=3D REQ_OP_WRITE_ZEROES || + bio_flagged(bio, BIO_DMA_TAGGED); } =20 static inline void *bio_data(struct bio *bio) @@ -98,9 +104,11 @@ static inline void bio_advance_iter(const struct bio = *bio, { iter->bi_sector +=3D bytes >> 9; =20 - if (bio_no_advance_iter(bio)) + if (bio_no_advance_iter(bio)) { iter->bi_size -=3D bytes; - else + if (bio_flagged(bio, BIO_DMA_TAGGED)) + iter->bi_bvec_done +=3D bytes; + } else bvec_iter_advance(bio->bi_io_vec, iter, bytes); /* TODO: It is reasonable to complete bio with error here. */ } @@ -225,11 +233,6 @@ static inline void bio_cnt_set(struct bio *bio, unsi= gned int count) atomic_set(&bio->__bi_cnt, count); } =20 -static inline bool bio_flagged(struct bio *bio, unsigned int bit) -{ - return (bio->bi_flags & (1U << bit)) !=3D 0; -} - static inline void bio_set_flag(struct bio *bio, unsigned int bit) { bio->bi_flags |=3D (1U << bit); @@ -447,7 +450,7 @@ static inline void bio_wouldblock_error(struct bio *b= io) */ static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_s= egs) { - if (iov_iter_is_bvec(iter)) + if (iov_iter_is_bvec(iter) || iov_iter_is_dma_tag(iter)) return 0; return iov_iter_npages(iter, max_segs); } diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index e10aabb36c2c..3eb045a9ba41 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -1141,6 +1141,18 @@ static inline int blk_rq_map_sg(struct request_que= ue *q, struct request *rq, } void blk_dump_rq_flags(struct request *, char *); =20 +static inline void *blk_rq_dma_tag(struct request *rq) +{ + return rq->bio && bio_flagged(rq->bio, BIO_DMA_TAGGED) ? + rq->bio->bi_dma_tag : 0; +} + +static inline size_t blk_rq_dma_offset(struct request *rq) +{ + return rq->bio && bio_flagged(rq->bio, BIO_DMA_TAGGED) ? + rq->bio->bi_iter.bi_bvec_done : 0; +} + #ifdef CONFIG_BLK_DEV_ZONED static inline unsigned int blk_rq_zone_no(struct request *rq) { diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 1ef99790f6ed..ea6db439acbe 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -299,7 +299,10 @@ struct bio { =20 atomic_t __bi_cnt; /* pin count */ =20 - struct bio_vec *bi_io_vec; /* the actual vec list */ + union { + struct bio_vec *bi_io_vec; /* the actual vec list */ + void *bi_dma_tag; /* driver specific tag */ + }; =20 struct bio_set *bi_pool; =20 @@ -334,6 +337,7 @@ enum { BIO_QOS_MERGED, /* but went through rq_qos merge path */ BIO_REMAPPED, BIO_ZONE_WRITE_LOCKED, /* Owns a zoned device zone write lock */ + BIO_DMA_TAGGED, /* Using premmaped dma buffers */ BIO_FLAG_LAST }; =20 --=20 2.30.2