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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 B2A9CC3A5A9 for ; Sat, 18 Apr 2020 16:46:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9E85722242 for ; Sat, 18 Apr 2020 16:46:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726625AbgDRQqt (ORCPT ); Sat, 18 Apr 2020 12:46:49 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:47074 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725923AbgDRQqt (ORCPT ); Sat, 18 Apr 2020 12:46:49 -0400 Received: by mail-pg1-f193.google.com with SMTP id 188so2766161pgj.13; Sat, 18 Apr 2020 09:46:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:autocrypt :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=GWknpOiP7uvC2PT0tJKduvW5TIp5mEE0CRJpCWZXxRw=; b=BLKDhuJrtkKSUfzL9KMXas5jnnVLNARgEiSunL7+jQdGe2OJ7xTCxrXWhLlluOMHFC AfDBThk/j2/sEKWuBpDYVHU9dlZQ8tGMv1OihJA9eCpDXqOuDMM1s4HLr8QhaAsno0c4 3mu+vuMH9Oe1pk18hnKzKyKx3EVQDvPxpcRDMhK5GiTHBkZcJjOQxP2eZge2Mo8v5TgI 1VA1EpEutBlS68IpbPyj0y6DbMpYkzB1u1LxEDaZwprHQ2+jxtFREHyEqG7X2MG2hQ4Q CICIzE9dkvRfZjpTXVZZ5l4551RGcN0gzbj2PbzBmPfo3MW4sCHVpNowQ1mQ/kwsFntv zEqg== X-Gm-Message-State: AGi0PubzrTqSKjYfTIGKBmF1A9W0Az3plfBg8ZuxUlVfRe2MbBSSLBV8 kM0ex/XXpb8i/pheTz2/WOE= X-Google-Smtp-Source: APiQypIrflAd9+tX0/9gTKSPIFlgllNyiimfnNEuue0C5WqRMWn+iI7/okl9Rv8x3c5gksvzJVNxyg== X-Received: by 2002:a62:7d11:: with SMTP id y17mr8671286pfc.127.1587228408072; Sat, 18 Apr 2020 09:46:48 -0700 (PDT) Received: from ?IPv6:2601:647:4000:d7:551:c132:d476:f445? ([2601:647:4000:d7:551:c132:d476:f445]) by smtp.gmail.com with ESMTPSA id n9sm9066458pjt.29.2020.04.18.09.46.45 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 18 Apr 2020 09:46:47 -0700 (PDT) Subject: Re: [PATCH v7 04/11] block: Introduce REQ_OP_ZONE_APPEND 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" , Daniel Wagner , Christoph Hellwig References: <20200417121536.5393-1-johannes.thumshirn@wdc.com> <20200417121536.5393-5-johannes.thumshirn@wdc.com> From: Bart Van Assche Autocrypt: addr=bvanassche@acm.org; prefer-encrypt=mutual; keydata= mQENBFSOu4oBCADcRWxVUvkkvRmmwTwIjIJvZOu6wNm+dz5AF4z0FHW2KNZL3oheO3P8UZWr LQOrCfRcK8e/sIs2Y2D3Lg/SL7qqbMehGEYcJptu6mKkywBfoYbtBkVoJ/jQsi2H0vBiiCOy fmxMHIPcYxaJdXxrOG2UO4B60Y/BzE6OrPDT44w4cZA9DH5xialliWU447Bts8TJNa3lZKS1 AvW1ZklbvJfAJJAwzDih35LxU2fcWbmhPa7EO2DCv/LM1B10GBB/oQB5kvlq4aA2PSIWkqz4 3SI5kCPSsygD6wKnbRsvNn2mIACva6VHdm62A7xel5dJRfpQjXj2snd1F/YNoNc66UUTABEB AAG0JEJhcnQgVmFuIEFzc2NoZSA8YnZhbmFzc2NoZUBhY20ub3JnPokBOQQTAQIAIwUCVI67 igIbAwcLCQgHAwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJEHFcPTXFzhAJ8QkH/1AdXblKL65M Y1Zk1bYKnkAb4a98LxCPm/pJBilvci6boefwlBDZ2NZuuYWYgyrehMB5H+q+Kq4P0IBbTqTa jTPAANn62A6jwJ0FnCn6YaM9TZQjM1F7LoDX3v+oAkaoXuq0dQ4hnxQNu792bi6QyVdZUvKc macVFVgfK9n04mL7RzjO3f+X4midKt/s+G+IPr4DGlrq+WH27eDbpUR3aYRk8EgbgGKvQFdD CEBFJi+5ZKOArmJVBSk21RHDpqyz6Vit3rjep7c1SN8s7NhVi9cjkKmMDM7KYhXkWc10lKx2 RTkFI30rkDm4U+JpdAd2+tP3tjGf9AyGGinpzE2XY1K5AQ0EVI67igEIAKiSyd0nECrgz+H5 PcFDGYQpGDMTl8MOPCKw/F3diXPuj2eql4xSbAdbUCJzk2ETif5s3twT2ER8cUTEVOaCEUY3 eOiaFgQ+nGLx4BXqqGewikPJCe+UBjFnH1m2/IFn4T9jPZkV8xlkKmDUqMK5EV9n3eQLkn5g lco+FepTtmbkSCCjd91EfThVbNYpVQ5ZjdBCXN66CKyJDMJ85HVr5rmXG/nqriTh6cv1l1Js T7AFvvPjUPknS6d+BETMhTkbGzoyS+sywEsQAgA+BMCxBH4LvUmHYhpS+W6CiZ3ZMxjO8Hgc ++w1mLeRUvda3i4/U8wDT3SWuHcB3DWlcppECLkAEQEAAYkBHwQYAQIACQUCVI67igIbDAAK CRBxXD01xc4QCZ4dB/0QrnEasxjM0PGeXK5hcZMT9Eo998alUfn5XU0RQDYdwp6/kMEXMdmT oH0F0xB3SQ8WVSXA9rrc4EBvZruWQ+5/zjVrhhfUAx12CzL4oQ9Ro2k45daYaonKTANYG22y //x8dLe2Fv1By4SKGhmzwH87uXxbTJAUxiWIi1np0z3/RDnoVyfmfbbL1DY7zf2hYXLLzsJR mSsED/1nlJ9Oq5fALdNEPgDyPUerqHxcmIub+pF0AzJoYHK5punqpqfGmqPbjxrJLPJfHVKy goMj5DlBMoYqEgpbwdUYkH6QdizJJCur4icy8GUNbisFYABeoJ91pnD4IGei3MTdvINSZI5e Message-ID: <373bc820-95f2-5728-c102-c4ca9fa8eea5@acm.org> Date: Sat, 18 Apr 2020 09:46:45 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200417121536.5393-5-johannes.thumshirn@wdc.com> Content-Type: text/plain; charset=utf-8 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 2020-04-17 05:15, Johannes Thumshirn wrote: > From: Keith Busch > > Define REQ_OP_ZONE_APPEND to append-write sectors to a zone of a zoned > block device. This is a no-merge write operation. > > A zone append write BIO must: > * Target a zoned block device > * Have a sector position indicating the start sector of the target zone Why the start sector instead of any sector in the target zone? Wouldn't the latter make it easier to write software that uses REQ_OP_ZONE_APPEND? > * The target zone must be a sequential write zone > * The BIO must not cross a zone boundary > * The BIO size must not be split to ensure that a single range of LBAs > is written with a single command. "BIO size must" -> "BIO must"? > diff --git a/block/bio.c b/block/bio.c > index 0f0e337e46b4..97baadc6d964 100644 > --- a/block/bio.c > +++ b/block/bio.c > @@ -1006,7 +1006,7 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) > put_page(page); > } else { > if (WARN_ON_ONCE(bio_full(bio, len))) > - return -EINVAL; > + return -EINVAL; > __bio_add_page(bio, page, len, offset); > } > offset = 0; Has the 'return' statement been indented correctly? I see a tab and a space in front of that statement instead of only a tab. > @@ -1451,6 +1501,10 @@ struct bio *bio_split(struct bio *bio, int sectors, > BUG_ON(sectors <= 0); > BUG_ON(sectors >= bio_sectors(bio)); > > + /* Zone append commands cannot be split */ > + if (WARN_ON_ONCE(bio_op(bio) == REQ_OP_ZONE_APPEND)) > + return NULL; > + > split = bio_clone_fast(bio, gfp, bs); > if (!split) > return NULL; Zone append commands -> Zone append bio's? > +/* > + * Check write append to a zoned block device. > + */ > +static inline blk_status_t blk_check_zone_append(struct request_queue *q, > + struct bio *bio) > +{ > + sector_t pos = bio->bi_iter.bi_sector; > + int nr_sectors = bio_sectors(bio); > + > + /* Only applicable to zoned block devices */ > + if (!blk_queue_is_zoned(q)) > + return BLK_STS_NOTSUPP; > + > + /* The bio sector must point to the start of a sequential zone */ > + if (pos & (blk_queue_zone_sectors(q) - 1) || > + !blk_queue_zone_is_seq(q, pos)) > + return BLK_STS_IOERR; > + > + /* > + * Not allowed to cross zone boundaries. Otherwise, the BIO will be > + * split and could result in non-contiguous sectors being written in > + * different zones. > + */ > + if (blk_queue_zone_no(q, pos) != blk_queue_zone_no(q, pos + nr_sectors)) > + return BLK_STS_IOERR; Can the above statement be simplified into the following? if (nr_sectors > q->limits.chunk_sectors) return BLK_STS_IOERR; > + /* Make sure the BIO is small enough and will not get split */ > + if (nr_sectors > q->limits.max_zone_append_sectors) > + return BLK_STS_IOERR; Do we really need a new request queue limit parameter? In which cases will max_zone_append_sectors differ from the zone size? Thanks, Bart.