From patchwork Fri Jul 15 16:47:33 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 104860 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [140.186.70.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 974E0B6F54 for ; Sat, 16 Jul 2011 03:09:54 +1000 (EST) Received: from localhost ([::1]:48453 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qhltd-0007FX-IS for incoming@patchwork.ozlabs.org; Fri, 15 Jul 2011 13:09:49 -0400 Received: from eggs.gnu.org ([140.186.70.92]:54693) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QhlVZ-0000Z2-VF for qemu-devel@nongnu.org; Fri, 15 Jul 2011 12:44:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QhlVX-0005ux-KM for qemu-devel@nongnu.org; Fri, 15 Jul 2011 12:44:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60334) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QhlVX-0005ui-2m for qemu-devel@nongnu.org; Fri, 15 Jul 2011 12:44:55 -0400 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p6FGipQZ023002 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 15 Jul 2011 12:44:51 -0400 Received: from dhcp-5-188.str.redhat.com (vpn1-4-172.ams2.redhat.com [10.36.4.172]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id p6FGijW3009993; Fri, 15 Jul 2011 12:44:50 -0400 From: Kevin Wolf To: qemu-devel@nongnu.org Date: Fri, 15 Jul 2011 18:47:33 +0200 Message-Id: <1310748459-2119-4-git-send-email-kwolf@redhat.com> In-Reply-To: <1310748459-2119-1-git-send-email-kwolf@redhat.com> References: <1310748459-2119-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.12 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 209.132.183.28 Cc: kwolf@redhat.com, stefanha@gmail.com Subject: [Qemu-devel] [RFC][PATCH 3/9] block: Add bdrv_co_readv/writev emulation X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org In order to be able to call bdrv_co_readv/writev for drivers that don't implement the functions natively, add an emulation that uses the AIO functions to implement them. Signed-off-by: Kevin Wolf --- block.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++++++------ trace-events | 1 + 2 files changed, 78 insertions(+), 9 deletions(-) diff --git a/block.c b/block.c index 79a5008..fc1712f 100644 --- a/block.c +++ b/block.c @@ -64,6 +64,12 @@ static BlockDriverAIOCB *bdrv_co_aio_readv_em(BlockDriverState *bs, static BlockDriverAIOCB *bdrv_co_aio_writev_em(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, BlockDriverCompletionFunc *cb, void *opaque); +static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, + int64_t sector_num, int nb_sectors, + QEMUIOVector *iov); +static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, + int64_t sector_num, int nb_sectors, + QEMUIOVector *iov); static QTAILQ_HEAD(, BlockDriverState) bdrv_states = QTAILQ_HEAD_INITIALIZER(bdrv_states); @@ -182,14 +188,19 @@ void bdrv_register(BlockDriver *bdrv) bdrv->bdrv_aio_writev = bdrv_co_aio_writev_em; bdrv->bdrv_read = bdrv_read_em; bdrv->bdrv_write = bdrv_write_em; - } else if (!bdrv->bdrv_aio_readv) { - /* add AIO emulation layer */ - bdrv->bdrv_aio_readv = bdrv_aio_readv_em; - bdrv->bdrv_aio_writev = bdrv_aio_writev_em; - } else if (!bdrv->bdrv_read) { - /* add synchronous IO emulation layer */ - bdrv->bdrv_read = bdrv_read_em; - bdrv->bdrv_write = bdrv_write_em; + } else { + bdrv->bdrv_co_readv = bdrv_co_readv_em; + bdrv->bdrv_co_writev = bdrv_co_writev_em; + + if (!bdrv->bdrv_aio_readv) { + /* add AIO emulation layer */ + bdrv->bdrv_aio_readv = bdrv_aio_readv_em; + bdrv->bdrv_aio_writev = bdrv_aio_writev_em; + } else if (!bdrv->bdrv_read) { + /* add synchronous IO emulation layer */ + bdrv->bdrv_read = bdrv_read_em; + bdrv->bdrv_write = bdrv_write_em; + } } if (!bdrv->bdrv_aio_flush) @@ -2652,7 +2663,7 @@ static void coroutine_fn bdrv_co_rw(void *opaque) BlockDriverAIOCBCoroutine *acb = opaque; BlockDriverState *bs = acb->common.bs; - if (acb->is_write) { + if (!acb->is_write) { acb->req.error = bs->drv->bdrv_co_readv(bs, acb->req.sector, acb->req.nb_sectors, acb->req.qiov); } else { @@ -2849,6 +2860,63 @@ void qemu_aio_release(void *p) } /**************************************************************/ +/* Coroutine block device emulation */ + +typedef struct CoroutineIOCompletion { + Coroutine *coroutine; + int ret; +} CoroutineIOCompletion; + +static void bdrv_co_io_em_complete(void *opaque, int ret) +{ + CoroutineIOCompletion *co = opaque; + + co->ret = ret; + qemu_coroutine_enter(co->coroutine, NULL); +} + +static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t sector_num, + int nb_sectors, QEMUIOVector *iov, + bool is_write) +{ + CoroutineIOCompletion co = { + .coroutine = qemu_coroutine_self(), + .ret = -EINPROGRESS, + }; + BlockDriverAIOCB *acb; + + if (is_write) { + acb = bdrv_aio_writev(bs, sector_num, iov, nb_sectors, + bdrv_co_io_em_complete, &co); + } else { + acb = bdrv_aio_readv(bs, sector_num, iov, nb_sectors, + bdrv_co_io_em_complete, &co); + } + + trace_bdrv_co_io(is_write, acb); + if (!acb) { + return -EIO; + } + qemu_coroutine_yield(); + + return co.ret; +} + +static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, + int64_t sector_num, int nb_sectors, + QEMUIOVector *iov) +{ + return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, false); +} + +static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, + int64_t sector_num, int nb_sectors, + QEMUIOVector *iov) +{ + return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true); +} + +/**************************************************************/ /* removable device support */ /** diff --git a/trace-events b/trace-events index 3cd9118..b835c61 100644 --- a/trace-events +++ b/trace-events @@ -57,6 +57,7 @@ disable bdrv_aio_writev(void *bs, int64_t sector_num, int nb_sectors, void *opaq disable bdrv_set_locked(void *bs, int locked) "bs %p locked %d" disable bdrv_co_readv(void *bs, int64_t sector_num, int nb_sector) "bs %p sector_num %"PRId64" nb_sectors %d" disable bdrv_co_writev(void *bs, int64_t sector_num, int nb_sector) "bs %p sector_num %"PRId64" nb_sectors %d" +disable bdrv_co_io(int is_write, void *acb) "is_write %d acb %p" # hw/virtio-blk.c disable virtio_blk_req_complete(void *req, int status) "req %p status %d"