From patchwork Thu Mar 17 15:56:34 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 8612781 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 232D9C0553 for ; Thu, 17 Mar 2016 16:09:21 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6F78A2020F for ; Thu, 17 Mar 2016 16:09:20 +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 9C221201F2 for ; Thu, 17 Mar 2016 16:09:19 +0000 (UTC) Received: from localhost ([::1]:36260 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1agaUA-000310-SX for patchwork-qemu-devel@patchwork.kernel.org; Thu, 17 Mar 2016 12:09:18 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38006) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1agaIY-0002WQ-GL for qemu-devel@nongnu.org; Thu, 17 Mar 2016 11:57:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1agaIX-0001pZ-Ci for qemu-devel@nongnu.org; Thu, 17 Mar 2016 11:57:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36899) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1agaIU-0001ns-Mh; Thu, 17 Mar 2016 11:57:14 -0400 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (Postfix) with ESMTPS id 3DCA4627C0; Thu, 17 Mar 2016 15:57:14 +0000 (UTC) Received: from noname.redhat.com (ovpn-116-71.ams2.redhat.com [10.36.116.71]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u2HFuj1R010106; Thu, 17 Mar 2016 11:57:13 -0400 From: Kevin Wolf To: qemu-block@nongnu.org Date: Thu, 17 Mar 2016 16:56:34 +0100 Message-Id: <1458230202-29136-22-git-send-email-kwolf@redhat.com> In-Reply-To: <1458230202-29136-1-git-send-email-kwolf@redhat.com> References: <1458230202-29136-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Thu, 17 Mar 2016 15:57:14 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Cc: kwolf@redhat.com, qemu-devel@nongnu.org Subject: [Qemu-devel] [PULL 21/29] block: Use blk_co_preadv() for blk_read() 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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org 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 patch introduces blk_co_preadv() as a central function on the BlockBackend level that is supposed to handle all read requests from the BB to its root BDS eventually. Signed-off-by: Kevin Wolf --- block/block-backend.c | 64 ++++++++++++++++++++++++++++++++++++++++++++--- block/io.c | 5 +--- include/block/block_int.h | 4 +++ 3 files changed, 65 insertions(+), 8 deletions(-) diff --git a/block/block-backend.c b/block/block-backend.c index 5de7850..c058785 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -22,6 +22,8 @@ /* Number of coroutines to reserve per attached device model */ #define COROUTINE_POOL_RESERVATION 64 +#define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ + static AioContext *blk_aiocb_get_aio_context(BlockAIOCB *acb); struct BlockBackend { @@ -693,15 +695,69 @@ static int blk_check_request(BlockBackend *blk, int64_t sector_num, nb_sectors * BDRV_SECTOR_SIZE); } -int blk_read(BlockBackend *blk, int64_t sector_num, uint8_t *buf, - int nb_sectors) +static int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset, + unsigned int bytes, QEMUIOVector *qiov, + BdrvRequestFlags flags) { - int ret = blk_check_request(blk, sector_num, nb_sectors); + int ret = blk_check_byte_request(blk, offset, bytes); if (ret < 0) { return ret; } - return bdrv_read(blk_bs(blk), sector_num, buf, nb_sectors); + return bdrv_co_do_preadv(blk_bs(blk), offset, bytes, qiov, flags); +} + +typedef struct BlkRwCo { + BlockBackend *blk; + int64_t offset; + QEMUIOVector *qiov; + int ret; + BdrvRequestFlags flags; +} BlkRwCo; + +static void blk_read_entry(void *opaque) +{ + BlkRwCo *rwco = opaque; + + rwco->ret = blk_co_preadv(rwco->blk, rwco->offset, rwco->qiov->size, + rwco->qiov, rwco->flags); +} + +int blk_read(BlockBackend *blk, int64_t sector_num, uint8_t *buf, + int nb_sectors) +{ + AioContext *aio_context; + QEMUIOVector qiov; + struct iovec iov; + Coroutine *co; + BlkRwCo rwco; + + if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { + return -EINVAL; + } + + iov = (struct iovec) { + .iov_base = buf, + .iov_len = nb_sectors * BDRV_SECTOR_SIZE, + }; + qemu_iovec_init_external(&qiov, &iov, 1); + + rwco = (BlkRwCo) { + .blk = blk, + .offset = sector_num << BDRV_SECTOR_BITS, + .qiov = &qiov, + .ret = NOT_DONE, + }; + + co = qemu_coroutine_create(blk_read_entry); + qemu_coroutine_enter(co, &rwco); + + aio_context = blk_get_aio_context(blk); + while (rwco.ret == NOT_DONE) { + aio_poll(aio_context, true); + } + + return rwco.ret; } int blk_read_unthrottled(BlockBackend *blk, int64_t sector_num, uint8_t *buf, diff --git a/block/io.c b/block/io.c index 5f9b6d6..c7084e4 100644 --- a/block/io.c +++ b/block/io.c @@ -44,9 +44,6 @@ static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *iov); -static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, - int64_t offset, unsigned int bytes, QEMUIOVector *qiov, - BdrvRequestFlags flags); static int coroutine_fn bdrv_co_do_pwritev(BlockDriverState *bs, int64_t offset, unsigned int bytes, QEMUIOVector *qiov, BdrvRequestFlags flags); @@ -939,7 +936,7 @@ out: /* * Handle a read request in coroutine context */ -static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, +int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, int64_t offset, unsigned int bytes, QEMUIOVector *qiov, BdrvRequestFlags flags) { diff --git a/include/block/block_int.h b/include/block/block_int.h index c031db4..b78be8d 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -508,6 +508,10 @@ extern BlockDriver bdrv_qcow2; */ void bdrv_setup_io_funcs(BlockDriver *bdrv); +int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs, + int64_t offset, unsigned int bytes, QEMUIOVector *qiov, + BdrvRequestFlags flags); + int get_tmp_filename(char *filename, int size); BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, const char *filename);