From nobody Thu Nov 13 23:24:14 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=virtuozzo.com ARC-Seal: i=1; a=rsa-sha256; t=1583143636; cv=none; d=zohomail.com; s=zohoarc; b=ep3hncBabNtWTndITpvOCCCHEe3l0WC4G81qDD+IylTccv0Clyc6C1FrU13kzcNFoW9q1DSfgWoU5slovld39jID79xM9E7QGKhADzmOhskNfggr7Q8jig3uoT28TLrpb/FrwxJvGeJfgl8VJvZsG7EXI0elTJA8dsJSH50VSxo= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1583143636; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=pVltROmI9YCbXfvP5f9CT29ApLr5NRoPgEE9sHtrHck=; b=KXEjGp5eOyMrpyAYKUt+F1Ldrs0bpPynLSMvygYXMno2vt/PJSAP8YXiA12zWTVRnBgVIE37NV0HbCKezvFnlo8aZQLxWo2KdinicXL0LREAhdk/STiKvF9iukLe6+QiWcOvb8lhNgICDPlffMoF77XmdBhtDOxhWcaI6ERTFL0= ARC-Authentication-Results: i=1; mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1583143636345341.4603662644663; Mon, 2 Mar 2020 02:07:16 -0800 (PST) Received: from localhost ([::1]:57852 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j8hyl-00070N-54 for importer@patchew.org; Mon, 02 Mar 2020 05:07:15 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:50784) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j8hxV-0004WR-Hs for qemu-devel@nongnu.org; Mon, 02 Mar 2020 05:05:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j8hxU-0007lh-CN for qemu-devel@nongnu.org; Mon, 02 Mar 2020 05:05:57 -0500 Received: from relay.sw.ru ([185.231.240.75]:48176) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j8hxR-0007jM-S7; Mon, 02 Mar 2020 05:05:54 -0500 Received: from vovaso.qa.sw.ru ([10.94.3.0] helo=kvm.qa.sw.ru) by relay.sw.ru with esmtp (Exim 4.92.3) (envelope-from ) id 1j8hxI-000350-77; Mon, 02 Mar 2020 13:05:44 +0300 From: Vladimir Sementsov-Ogievskiy To: qemu-block@nongnu.org Subject: [PATCH 3/5] block: add max_pwrite_zeroes_no_fallback to BlockLimits Date: Mon, 2 Mar 2020 13:05:35 +0300 Message-Id: <20200302100537.29058-4-vsementsov@virtuozzo.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20200302100537.29058-1-vsementsov@virtuozzo.com> References: <20200302100537.29058-1-vsementsov@virtuozzo.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 185.231.240.75 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: fam@euphon.net, kwolf@redhat.com, vsementsov@virtuozzo.com, qemu-devel@nongnu.org, mreitz@redhat.com, stefanha@redhat.com, den@openvz.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" NBD spec is updated, so that max_block doesn't relate to NBD_CMD_WRITE_ZEROES with NBD_CMD_FLAG_FAST_ZERO (which mirrors Qemu flag BDRV_REQ_NO_FALLBACK). To drop the restriction we need new max_pwrite_zeroes_no_fallback. Default value of new max_pwrite_zeroes_no_fallback is zero and it means no-restriction, so we are automatically done by this commit. Note that nbd and blkdebug are the only drivers which in the same time define max_pwrite_zeroes limit and support BDRV_REQ_NO_FALLBACK, so we need to update only blkdebug. Signed-off-by: Vladimir Sementsov-Ogievskiy --- include/block/block_int.h | 8 ++++++++ block/blkdebug.c | 7 ++++++- block/io.c | 4 +++- 3 files changed, 17 insertions(+), 2 deletions(-) diff --git a/include/block/block_int.h b/include/block/block_int.h index 6f9fd5e20e..c167e887c6 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -618,6 +618,14 @@ typedef struct BlockLimits { * pwrite_zeroes_alignment. May be 0 if no inherent 32-bit limit */ int32_t max_pwrite_zeroes; =20 + /* + * Maximum number of bytes that can zeroized at once if flag + * BDRV_REQ_NO_FALLBACK specified (since it is signed, it must be < 2G= , if + * set). Must be multiple of pwrite_zeroes_alignment. May be 0 if no + * inherent 32-bit limit. + */ + int32_t max_pwrite_zeroes_no_fallback; + /* Optimal alignment for write zeroes requests in bytes. A power * of 2 is best but not mandatory. Must be a multiple of * bl.request_alignment, and must be less than max_pwrite_zeroes diff --git a/block/blkdebug.c b/block/blkdebug.c index af44aa973f..7627fbcb3b 100644 --- a/block/blkdebug.c +++ b/block/blkdebug.c @@ -692,7 +692,11 @@ static int coroutine_fn blkdebug_co_pwrite_zeroes(Bloc= kDriverState *bs, } assert(QEMU_IS_ALIGNED(offset, align)); assert(QEMU_IS_ALIGNED(bytes, align)); - if (bs->bl.max_pwrite_zeroes) { + if ((flags & BDRV_REQ_NO_FALLBACK) && + bs->bl.max_pwrite_zeroes_no_fallback) + { + assert(bytes <=3D bs->bl.max_pwrite_zeroes_no_fallback); + } else if (bs->bl.max_pwrite_zeroes) { assert(bytes <=3D bs->bl.max_pwrite_zeroes); } =20 @@ -977,6 +981,7 @@ static void blkdebug_refresh_limits(BlockDriverState *b= s, Error **errp) } if (s->max_write_zero) { bs->bl.max_pwrite_zeroes =3D s->max_write_zero; + bs->bl.max_pwrite_zeroes_no_fallback =3D s->max_write_zero; } if (s->opt_discard) { bs->bl.pdiscard_alignment =3D s->opt_discard; diff --git a/block/io.c b/block/io.c index 7e4cb74cf4..75fd5600c2 100644 --- a/block/io.c +++ b/block/io.c @@ -1752,7 +1752,9 @@ static int coroutine_fn bdrv_co_do_pwrite_zeroes(Bloc= kDriverState *bs, int head =3D 0; int tail =3D 0; =20 - int max_write_zeroes =3D MIN_NON_ZERO(bs->bl.max_pwrite_zeroes, INT_MA= X); + int max_write_zeroes =3D MIN_NON_ZERO((flags & BDRV_REQ_NO_FALLBACK) ? + bs->bl.max_pwrite_zeroes_no_fallba= ck : + bs->bl.max_pwrite_zeroes, INT_MAX); int alignment =3D MAX(bs->bl.pwrite_zeroes_alignment, bs->bl.request_alignment); int max_transfer =3D MIN_NON_ZERO(bs->bl.max_transfer, MAX_BOUNCE_BUFF= ER); --=20 2.21.0