From patchwork Tue May 15 15:39:58 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 913761 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 40lhkh5z1Zz9s02 for ; Wed, 16 May 2018 01:46:36 +1000 (AEST) Received: from localhost ([::1]:44413 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fIc9o-0002dq-Lt for incoming@patchwork.ozlabs.org; Tue, 15 May 2018 11:46:32 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38496) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fIc4G-0006Sg-VN for qemu-devel@nongnu.org; Tue, 15 May 2018 11:40:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fIc4F-0001HL-Dp for qemu-devel@nongnu.org; Tue, 15 May 2018 11:40:48 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:47536 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fIc4A-0001D8-7c; Tue, 15 May 2018 11:40:42 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C3F937CBBA; Tue, 15 May 2018 15:40:41 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-117-164.ams2.redhat.com [10.36.117.164]) by smtp.corp.redhat.com (Postfix) with ESMTP id 22ADC200BC1E; Tue, 15 May 2018 15:40:41 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Date: Tue, 15 May 2018 17:39:58 +0200 Message-Id: <20180515154033.19899-3-kwolf@redhat.com> In-Reply-To: <20180515154033.19899-1-kwolf@redhat.com> References: <20180515154033.19899-1-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Tue, 15 May 2018 15:40:41 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Tue, 15 May 2018 15:40:41 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'kwolf@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PULL 02/37] block: Support byte-based aio callbacks X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Eric Blake We are gradually moving away from sector-based interfaces, towards byte-based. Add new sector-based aio callbacks for read and write, to match the fact that bdrv_aio_pdiscard is already byte-based. Ideally, drivers should be converted to use coroutine callbacks rather than aio; but that is not quite as trivial (and if we were to do that conversion, the null-aio driver would disappear), so for the short term, converting the signature but keeping things with aio is easier. However, we CAN declare that a driver that uses the byte-based aio interfaces now defaults to byte-based operations, and must explicitly provide a refresh_limits override to stick with larger alignments (making the alignment issues more obvious directly in the drivers touched in the next few patches). Once all drivers are converted, the sector-based aio callbacks will be removed; in the meantime, a FIXME comment is added due to a slight inefficiency that will be touched up as part of that later cleanup. Simplify some instances of 'bs->drv' into 'drv' while touching this, since the local variable already exists to reduce typing. Signed-off-by: Eric Blake Signed-off-by: Kevin Wolf --- include/block/block_int.h | 6 ++++++ block/io.c | 38 +++++++++++++++++++++++++++++--------- 2 files changed, 35 insertions(+), 9 deletions(-) diff --git a/include/block/block_int.h b/include/block/block_int.h index c4dd1d4bb8..e772e3502b 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -144,9 +144,15 @@ struct BlockDriver { BlockAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, BlockCompletionFunc *cb, void *opaque); + BlockAIOCB *(*bdrv_aio_preadv)(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags, + BlockCompletionFunc *cb, void *opaque); BlockAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, BlockCompletionFunc *cb, void *opaque); + BlockAIOCB *(*bdrv_aio_pwritev)(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags, + BlockCompletionFunc *cb, void *opaque); BlockAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs, BlockCompletionFunc *cb, void *opaque); BlockAIOCB *(*bdrv_aio_pdiscard)(BlockDriverState *bs, diff --git a/block/io.c b/block/io.c index bd9a19a9c4..407bc25df4 100644 --- a/block/io.c +++ b/block/io.c @@ -92,7 +92,8 @@ void bdrv_refresh_limits(BlockDriverState *bs, Error **errp) } /* Default alignment based on whether driver has byte interface */ - bs->bl.request_alignment = drv->bdrv_co_preadv ? 1 : 512; + bs->bl.request_alignment = (drv->bdrv_co_preadv || + drv->bdrv_aio_preadv) ? 1 : 512; /* Take some limits from the children as a default */ if (bs->file) { @@ -924,12 +925,15 @@ static int coroutine_fn bdrv_driver_preadv(BlockDriverState *bs, return drv->bdrv_co_preadv(bs, offset, bytes, qiov, flags); } + /* FIXME - no need to calculate these if .bdrv_aio_preadv exists */ sector_num = offset >> BDRV_SECTOR_BITS; nb_sectors = bytes >> BDRV_SECTOR_BITS; - assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); - assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); - assert((bytes >> BDRV_SECTOR_BITS) <= BDRV_REQUEST_MAX_SECTORS); + if (!drv->bdrv_aio_preadv) { + assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); + assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); + assert((bytes >> BDRV_SECTOR_BITS) <= BDRV_REQUEST_MAX_SECTORS); + } if (drv->bdrv_co_readv) { return drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); @@ -939,8 +943,13 @@ static int coroutine_fn bdrv_driver_preadv(BlockDriverState *bs, .coroutine = qemu_coroutine_self(), }; - acb = bs->drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors, + if (drv->bdrv_aio_preadv) { + acb = drv->bdrv_aio_preadv(bs, offset, bytes, qiov, flags, + bdrv_co_io_em_complete, &co); + } else { + acb = drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors, bdrv_co_io_em_complete, &co); + } if (acb == NULL) { return -EIO; } else { @@ -972,12 +981,15 @@ static int coroutine_fn bdrv_driver_pwritev(BlockDriverState *bs, goto emulate_flags; } + /* FIXME - no need to calculate these if .bdrv_aio_pwritev exists */ sector_num = offset >> BDRV_SECTOR_BITS; nb_sectors = bytes >> BDRV_SECTOR_BITS; - assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); - assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); - assert((bytes >> BDRV_SECTOR_BITS) <= BDRV_REQUEST_MAX_SECTORS); + if (!drv->bdrv_aio_pwritev) { + assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); + assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); + assert((bytes >> BDRV_SECTOR_BITS) <= BDRV_REQUEST_MAX_SECTORS); + } if (drv->bdrv_co_writev_flags) { ret = drv->bdrv_co_writev_flags(bs, sector_num, nb_sectors, qiov, @@ -992,8 +1004,16 @@ static int coroutine_fn bdrv_driver_pwritev(BlockDriverState *bs, .coroutine = qemu_coroutine_self(), }; - acb = bs->drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors, + if (drv->bdrv_aio_pwritev) { + acb = drv->bdrv_aio_pwritev(bs, offset, bytes, qiov, + flags & bs->supported_write_flags, + bdrv_co_io_em_complete, &co); + flags &= ~bs->supported_write_flags; + } else { + assert(!bs->supported_write_flags); + acb = drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors, bdrv_co_io_em_complete, &co); + } if (acb == NULL) { ret = -EIO; } else {