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 X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 19718C47256 for ; Wed, 6 May 2020 18:16:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 047CD2075E for ; Wed, 6 May 2020 18:16:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729477AbgEFSQW (ORCPT ); Wed, 6 May 2020 14:16:22 -0400 Received: from mx2.suse.de ([195.135.220.15]:45748 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728082AbgEFSQW (ORCPT ); Wed, 6 May 2020 14:16:22 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 662F1AEC5; Wed, 6 May 2020 18:16:23 +0000 (UTC) Subject: Re: [PATCH v10 1/9] block: rename __bio_add_pc_page to bio_add_hw_page To: Johannes Thumshirn , Jens Axboe Cc: Christoph Hellwig , linux-block , Damien Le Moal , Keith Busch , "linux-scsi @ vger . kernel . org" , "Martin K . Petersen" , "linux-fsdevel @ vger . kernel . org" , Christoph Hellwig , Daniel Wagner References: <20200506161145.9841-1-johannes.thumshirn@wdc.com> <20200506161145.9841-2-johannes.thumshirn@wdc.com> From: Hannes Reinecke Message-ID: Date: Wed, 6 May 2020 20:16:15 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <20200506161145.9841-2-johannes.thumshirn@wdc.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 5/6/20 6:11 PM, Johannes Thumshirn wrote: > From: Christoph Hellwig > > Rename __bio_add_pc_page() to bio_add_hw_page() and explicitly pass in a > max_sectors argument. > > This max_sectors argument can be used to specify constraints from the > hardware. > > Signed-off-by: Christoph Hellwig > [ jth: rebased and made public for blk-map.c ] > Signed-off-by: Johannes Thumshirn > Reviewed-by: Daniel Wagner > Reviewed-by: Martin K. Petersen > --- > block/bio.c | 65 ++++++++++++++++++++++++++++++------------------- > block/blk-map.c | 5 ++-- > block/blk.h | 4 +-- > 3 files changed, 45 insertions(+), 29 deletions(-) > > diff --git a/block/bio.c b/block/bio.c > index 21cbaa6a1c20..aad0a6dad4f9 100644 > --- a/block/bio.c > +++ b/block/bio.c > @@ -748,9 +748,14 @@ static inline bool page_is_mergeable(const struct bio_vec *bv, > return true; > } > > -static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio, > - struct page *page, unsigned len, unsigned offset, > - bool *same_page) > +/* > + * Try to merge a page into a segment, while obeying the hardware segment > + * size limit. This is not for normal read/write bios, but for passthrough > + * or Zone Append operations that we can't split. > + */ > +static bool bio_try_merge_hw_seg(struct request_queue *q, struct bio *bio, > + struct page *page, unsigned len, > + unsigned offset, bool *same_page) > { > struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; > unsigned long mask = queue_segment_boundary(q); > @@ -765,38 +770,32 @@ static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio, > } > > /** > - * __bio_add_pc_page - attempt to add page to passthrough bio > - * @q: the target queue > - * @bio: destination bio > - * @page: page to add > - * @len: vec entry length > - * @offset: vec entry offset > - * @same_page: return if the merge happen inside the same page > - * > - * Attempt to add a page to the bio_vec maplist. This can fail for a > - * number of reasons, such as the bio being full or target block device > - * limitations. The target block device must allow bio's up to PAGE_SIZE, > - * so it is always possible to add a single page to an empty bio. > + * bio_add_hw_page - attempt to add a page to a bio with hw constraints > + * @q: the target queue > + * @bio: destination bio > + * @page: page to add > + * @len: vec entry length > + * @offset: vec entry offset > + * @max_sectors: maximum number of sectors that can be added > + * @same_page: return if the segment has been merged inside the same page > * > - * This should only be used by passthrough bios. > + * Add a page to a bio while respecting the hardware max_sectors, max_segment > + * and gap limitations. > */ > -int __bio_add_pc_page(struct request_queue *q, struct bio *bio, > +int bio_add_hw_page(struct request_queue *q, struct bio *bio, > struct page *page, unsigned int len, unsigned int offset, > - bool *same_page) > + unsigned int max_sectors, bool *same_page) > { > struct bio_vec *bvec; > > - /* > - * cloned bio must not modify vec list > - */ > - if (unlikely(bio_flagged(bio, BIO_CLONED))) > + if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED))) > return 0; > > - if (((bio->bi_iter.bi_size + len) >> 9) > queue_max_hw_sectors(q)) > + if (((bio->bi_iter.bi_size + len) >> 9) > max_sectors) > return 0; > > if (bio->bi_vcnt > 0) { > - if (bio_try_merge_pc_page(q, bio, page, len, offset, same_page)) > + if (bio_try_merge_hw_seg(q, bio, page, len, offset, same_page)) > return len; > > /* > @@ -823,11 +822,27 @@ int __bio_add_pc_page(struct request_queue *q, struct bio *bio, > return len; > } > > +/** > + * bio_add_pc_page - attempt to add page to passthrough bio > + * @q: the target queue > + * @bio: destination bio > + * @page: page to add > + * @len: vec entry length > + * @offset: vec entry offset > + * > + * Attempt to add a page to the bio_vec maplist. This can fail for a > + * number of reasons, such as the bio being full or target block device > + * limitations. The target block device must allow bio's up to PAGE_SIZE, > + * so it is always possible to add a single page to an empty bio. > + * > + * This should only be used by passthrough bios. > + */ > int bio_add_pc_page(struct request_queue *q, struct bio *bio, > struct page *page, unsigned int len, unsigned int offset) > { > bool same_page = false; > - return __bio_add_pc_page(q, bio, page, len, offset, &same_page); > + return bio_add_hw_page(q, bio, page, len, offset, > + queue_max_hw_sectors(q), &same_page); > } > EXPORT_SYMBOL(bio_add_pc_page); > > diff --git a/block/blk-map.c b/block/blk-map.c > index b6fa343fea9f..e3e4ac48db45 100644 > --- a/block/blk-map.c > +++ b/block/blk-map.c > @@ -257,6 +257,7 @@ static struct bio *bio_copy_user_iov(struct request_queue *q, > static struct bio *bio_map_user_iov(struct request_queue *q, > struct iov_iter *iter, gfp_t gfp_mask) > { > + unsigned int max_sectors = queue_max_hw_sectors(q); > int j; > struct bio *bio; > int ret; > @@ -294,8 +295,8 @@ static struct bio *bio_map_user_iov(struct request_queue *q, > if (n > bytes) > n = bytes; > > - if (!__bio_add_pc_page(q, bio, page, n, offs, > - &same_page)) { > + if (!bio_add_hw_page(q, bio, page, n, offs, > + max_sectors, &same_page)) { > if (same_page) > put_page(page); > break; > diff --git a/block/blk.h b/block/blk.h > index 73bd3b1c6938..1ae3279df712 100644 > --- a/block/blk.h > +++ b/block/blk.h > @@ -453,8 +453,8 @@ static inline void part_nr_sects_write(struct hd_struct *part, sector_t size) > > struct request_queue *__blk_alloc_queue(int node_id); > > -int __bio_add_pc_page(struct request_queue *q, struct bio *bio, > +int bio_add_hw_page(struct request_queue *q, struct bio *bio, > struct page *page, unsigned int len, unsigned int offset, > - bool *same_page); > + unsigned int max_sectors, bool *same_page); > > #endif /* BLK_INTERNAL_H */ > Reviewed-by: Hannes Reinecke Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer