From patchwork Thu Apr 28 13:16:30 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 8970181 Return-Path: X-Original-To: patchwork-qemu-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id BD74FBF29F for ; Thu, 28 Apr 2016 13:17:33 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 21E25202C8 for ; Thu, 28 Apr 2016 13:17:33 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5EDBF200D6 for ; Thu, 28 Apr 2016 13:17:32 +0000 (UTC) Received: from localhost ([::1]:48998 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1avlox-0008Ri-I0 for patchwork-qemu-devel@patchwork.kernel.org; Thu, 28 Apr 2016 09:17:31 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37746) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1avloZ-0008C7-QI for qemu-devel@nongnu.org; Thu, 28 Apr 2016 09:17:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1avloU-0005bY-1f for qemu-devel@nongnu.org; Thu, 28 Apr 2016 09:17:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33095) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1avloM-0005Yl-Bf; Thu, 28 Apr 2016 09:16:54 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 12421C05E17F; Thu, 28 Apr 2016 13:16:54 +0000 (UTC) Received: from noname.redhat.com (ovpn-116-93.ams2.redhat.com [10.36.116.93]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u3SDGnCw001230; Thu, 28 Apr 2016 09:16:52 -0400 From: Kevin Wolf To: qemu-block@nongnu.org Date: Thu, 28 Apr 2016 15:16:30 +0200 Message-Id: <1461849406-29743-2-git-send-email-kwolf@redhat.com> In-Reply-To: <1461849406-29743-1-git-send-email-kwolf@redhat.com> References: <1461849406-29743-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v2 01/17] block: Introduce bdrv_driver_preadv() 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, famz@redhat.com, sw@weilnetz.de, qemu-devel@nongnu.org, mreitz@redhat.com, stefanha@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This is a function that simply calls into the block driver for doing a read, providing the byte granularity interface we want to eventually have everywhere, and using whatever interface that driver supports. For now, this is just a wrapper for calling bs->drv->bdrv_co_readv(). Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake --- block/io.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) diff --git a/block/io.c b/block/io.c index a7dbf85..586a46a 100644 --- a/block/io.c +++ b/block/io.c @@ -800,6 +800,21 @@ int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset, return 0; } +static int coroutine_fn bdrv_driver_preadv(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, int flags) +{ + BlockDriver *drv = bs->drv; + int64_t sector_num = offset >> BDRV_SECTOR_BITS; + unsigned int 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); + + return drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); +} + static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) { @@ -836,8 +851,9 @@ static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs, qemu_iovec_init_external(&bounce_qiov, &iov, 1); - ret = drv->bdrv_co_readv(bs, cluster_sector_num, cluster_nb_sectors, - &bounce_qiov); + ret = bdrv_driver_preadv(bs, cluster_sector_num * BDRV_SECTOR_SIZE, + cluster_nb_sectors * BDRV_SECTOR_SIZE, + &bounce_qiov, 0); if (ret < 0) { goto err; } @@ -880,7 +896,6 @@ static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, BdrvTrackedRequest *req, int64_t offset, unsigned int bytes, int64_t align, QEMUIOVector *qiov, int flags) { - BlockDriver *drv = bs->drv; int ret; int64_t sector_num = offset >> BDRV_SECTOR_BITS; @@ -921,7 +936,7 @@ static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, /* Forward the request to the BlockDriver */ if (!bs->zero_beyond_eof) { - ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); + ret = bdrv_driver_preadv(bs, offset, bytes, qiov, 0); } else { /* Read zeros after EOF */ int64_t total_sectors, max_nb_sectors; @@ -935,7 +950,7 @@ static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, max_nb_sectors = ROUND_UP(MAX(0, total_sectors - sector_num), align >> BDRV_SECTOR_BITS); if (nb_sectors < max_nb_sectors) { - ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); + ret = bdrv_driver_preadv(bs, offset, bytes, qiov, 0); } else if (max_nb_sectors > 0) { QEMUIOVector local_qiov; @@ -943,8 +958,9 @@ static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, qemu_iovec_concat(&local_qiov, qiov, 0, max_nb_sectors * BDRV_SECTOR_SIZE); - ret = drv->bdrv_co_readv(bs, sector_num, max_nb_sectors, - &local_qiov); + ret = bdrv_driver_preadv(bs, offset, + max_nb_sectors * BDRV_SECTOR_SIZE, + &local_qiov, 0); qemu_iovec_destroy(&local_qiov); } else {