From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:51409) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QqhxU-0005lJ-5w for qemu-devel@nongnu.org; Tue, 09 Aug 2011 04:46:45 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QqhxS-0002IU-Q7 for qemu-devel@nongnu.org; Tue, 09 Aug 2011 04:46:44 -0400 Received: from e37.co.us.ibm.com ([32.97.110.158]:48244) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QqhxS-0002GW-95 for qemu-devel@nongnu.org; Tue, 09 Aug 2011 04:46:42 -0400 Received: from d03relay05.boulder.ibm.com (d03relay05.boulder.ibm.com [9.17.195.107]) by e37.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id p798hW4O014546 for ; Tue, 9 Aug 2011 02:43:32 -0600 Received: from d03av03.boulder.ibm.com (d03av03.boulder.ibm.com [9.17.195.169]) by d03relay05.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p798kemk150146 for ; Tue, 9 Aug 2011 02:46:40 -0600 Received: from d03av03.boulder.ibm.com (loopback [127.0.0.1]) by d03av03.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p792kcZK018894 for ; Mon, 8 Aug 2011 20:46:39 -0600 Date: Tue, 9 Aug 2011 16:46:28 +0800 From: Ram Pai Message-ID: <20110809084628.GA17510@ram-ThinkPad-T61> References: <1312863472-6901-1-git-send-email-wuzhy@linux.vnet.ibm.com> <1312863472-6901-3-git-send-email-wuzhy@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1312863472-6901-3-git-send-email-wuzhy@linux.vnet.ibm.com> Subject: Re: [Qemu-devel] [PATCH v5 2/4] block: add the block queue support Reply-To: Ram Pai List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Zhi Yong Wu Cc: kwolf@redhat.com, pair@us.ibm.com, stefanha@linux.vnet.ibm.com, kvm@vger.kernel.org, mtosatti@redhat.com, qemu-devel@nongnu.org, zwu.kernel@gmail.com, ryanh@us.ibm.com, luowenj@cn.ibm.com On Tue, Aug 09, 2011 at 12:17:50PM +0800, Zhi Yong Wu wrote: > The patch introduce one block queue for QEMU block layer. > > Signed-off-by: Zhi Yong Wu > --- > block/blk-queue.c | 141 +++++++++++++++++++++++++++++++++++++++++++++++++++++ > block/blk-queue.h | 73 +++++++++++++++++++++++++++ > 2 files changed, 214 insertions(+), 0 deletions(-) > create mode 100644 block/blk-queue.c > create mode 100644 block/blk-queue.h > > diff --git a/block/blk-queue.c b/block/blk-queue.c > new file mode 100644 > index 0000000..f36f3e2 > --- /dev/null > +++ b/block/blk-queue.c > @@ -0,0 +1,141 @@ > +/* > + * QEMU System Emulator queue definition for block layer > + * > + * Copyright (c) 2011 Zhi Yong Wu > + * > + * Permission is hereby granted, free of charge, to any person obtaining a copy > + * of this software and associated documentation files (the "Software"), to deal > + * in the Software without restriction, including without limitation the rights > + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell > + * copies of the Software, and to permit persons to whom the Software is > + * furnished to do so, subject to the following conditions: > + * > + * The above copyright notice and this permission notice shall be included in > + * all copies or substantial portions of the Software. > + * > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL > + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, > + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN > + * THE SOFTWARE. > + */ > + > +#include "block_int.h" > +#include "qemu-queue.h" > +#include "block/blk-queue.h" > + > +/* The APIs for block request queue on qemu block layer. > + */ > + > +static void qemu_block_queue_cancel(BlockDriverAIOCB *acb) > +{ > + qemu_aio_release(acb); > +} > + > +static AIOPool block_queue_pool = { > + .aiocb_size = sizeof(struct BlockDriverAIOCB), > + .cancel = qemu_block_queue_cancel, > +}; > + > +static void qemu_block_queue_callback(void *opaque, int ret) > +{ > + BlockDriverAIOCB *acb = opaque; > + > + qemu_aio_release(acb); > +} > + > +BlockQueue *qemu_new_block_queue(void) > +{ > + BlockQueue *queue; > + > + queue = qemu_mallocz(sizeof(BlockQueue)); > + > + QTAILQ_INIT(&queue->requests); > + > + return queue; > +} > + > +void qemu_del_block_queue(BlockQueue *queue) > +{ > + BlockIORequest *request, *next; > + > + QTAILQ_FOREACH_SAFE(request, &queue->requests, entry, next) { > + QTAILQ_REMOVE(&queue->requests, request, entry); > + qemu_free(request); > + } > + > + qemu_free(queue); > +} > + > +BlockDriverAIOCB *qemu_block_queue_enqueue(BlockQueue *queue, > + BlockDriverState *bs, > + BlockRequestHandler *handler, > + int64_t sector_num, > + QEMUIOVector *qiov, > + int nb_sectors, > + BlockDriverCompletionFunc *cb, > + void *opaque) > +{ > + BlockIORequest *request; > + BlockDriverAIOCB *acb; > + > + request = qemu_malloc(sizeof(BlockIORequest)); > + request->bs = bs; > + request->handler = handler; > + request->sector_num = sector_num; > + request->qiov = qiov; > + request->nb_sectors = nb_sectors; > + request->cb = cb; > + request->opaque = opaque; > + > + QTAILQ_INSERT_TAIL(&queue->requests, request, entry); > + > + acb = qemu_aio_get(&block_queue_pool, bs, > + qemu_block_queue_callback, opaque); > + > + request->acb = acb; > + > + return acb; > +} > + > +int qemu_block_queue_handler(BlockIORequest *request) > +{ > + int ret; > + BlockDriverAIOCB *res; > + > + /* indicate this req is from block queue */ > + request->bs->req_from_queue = true; > + > + res = request->handler(request->bs, request->sector_num, > + request->qiov, request->nb_sectors, > + request->cb, request->opaque); should'nt you return with a failure here if res == NULL? Otherwise qemu_block_queue_callback() gets called which will release the acb. > + > + if (request->acb) { > + qemu_block_queue_callback(request->acb, 0); > + } > + > + ret = (res == NULL) ? 0 : 1; > + > + return ret; > +} RP