From patchwork Thu Oct 20 13:57:39 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhanghailiang X-Patchwork-Id: 9386955 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id AC3A7607D0 for ; Thu, 20 Oct 2016 14:22:09 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9D9C529C94 for ; Thu, 20 Oct 2016 14:22:09 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9231229C99; Thu, 20 Oct 2016 14:22:09 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 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.wl.linuxfoundation.org (Postfix) with ESMTPS id 07AD229C94 for ; Thu, 20 Oct 2016 14:22:08 +0000 (UTC) Received: from localhost ([::1]:55128 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bxEER-00005O-7a for patchwork-qemu-devel@patchwork.kernel.org; Thu, 20 Oct 2016 10:22:07 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36472) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bxDs8-0003Il-C0 for qemu-devel@nongnu.org; Thu, 20 Oct 2016 09:59:05 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bxDs5-0000VP-Qv for qemu-devel@nongnu.org; Thu, 20 Oct 2016 09:59:04 -0400 Received: from szxga03-in.huawei.com ([119.145.14.66]:29861) by eggs.gnu.org with esmtps (TLS1.0:RSA_ARCFOUR_SHA1:16) (Exim 4.71) (envelope-from ) id 1bxDs4-0000TS-Lu; Thu, 20 Oct 2016 09:59:01 -0400 Received: from 172.24.1.60 (EHLO szxeml432-hub.china.huawei.com) ([172.24.1.60]) by szxrg03-dlp.huawei.com (MOS 4.4.3-GA FastPath queued) with ESMTP id CJX49068; Thu, 20 Oct 2016 21:58:32 +0800 (CST) Received: from localhost (10.177.24.212) by szxeml432-hub.china.huawei.com (10.82.67.209) with Microsoft SMTP Server id 14.3.235.1; Thu, 20 Oct 2016 21:58:22 +0800 From: zhanghailiang To: , Date: Thu, 20 Oct 2016 21:57:39 +0800 Message-ID: <1476971860-20860-7-git-send-email-zhang.zhanghailiang@huawei.com> X-Mailer: git-send-email 2.7.2.windows.1 In-Reply-To: <1476971860-20860-1-git-send-email-zhang.zhanghailiang@huawei.com> References: <1476971860-20860-1-git-send-email-zhang.zhanghailiang@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.177.24.212] X-CFilter-Loop: Reflected X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] X-Received-From: 119.145.14.66 Subject: [Qemu-devel] [PATCH RFC 6/7] replication: Implement block replication for shared disk case 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, xiecl.fnst@cn.fujitsu.com, Zhang Chen , zhanghailiang , mreitz@redhat.com, stefanha@redhat.com, pbonzini@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP Just as the scenario of non-shared disk block replication, we are going to implement block replication from many basic blocks that are already in QEMU. The architecture is: virtio-blk || .---------- / || | Secondary / || '---------- / || virtio-blk / || | | || replication(5) | NBD --------> NBD (2) | | client || server ---> hidden disk <-- active disk(4) | ^ || | | replication(1) || | | | || | | +-----------------' || | (3) |drive-backup sync=none || | --------. | +-----------------+ || | Primary | | | || backing | --------' | | || | V | | +-------------------------------------------+ | | shared disk | <----------+ +-------------------------------------------+ 1) Primary writes will read original data and forward it to Secondary QEMU. 2) The hidden-disk is created automatically. It buffers the original content that is modified by the primary VM. It should also be an empty disk, and the driver supports bdrv_make_empty() and backing file. 3) Primary write requests will be written to Shared disk. 4) Secondary write requests will be buffered in the active disk and it will overwrite the existing sector content in the buffer. Signed-off-by: zhanghailiang Signed-off-by: Wen Congyang Signed-off-by: Zhang Chen --- block/replication.c | 45 ++++++++++++++++++++++++++++++++++++++------- 1 file changed, 38 insertions(+), 7 deletions(-) diff --git a/block/replication.c b/block/replication.c index 39c616d..e66b1ca 100644 --- a/block/replication.c +++ b/block/replication.c @@ -221,7 +221,7 @@ static coroutine_fn int replication_co_readv(BlockDriverState *bs, QEMUIOVector *qiov) { BDRVReplicationState *s = bs->opaque; - BdrvChild *child = s->secondary_disk; + BdrvChild *child = s->is_shared_disk ? s->primary_disk : s->secondary_disk; BlockJob *job = NULL; CowRequest req; int ret; @@ -398,8 +398,12 @@ static void backup_job_completed(void *opaque, int ret) /* The backup job is cancelled unexpectedly */ s->error = -EIO; } - - backup_job_cleanup(s); + if (s->mode == REPLICATION_MODE_PRIMARY) { + s->replication_state = BLOCK_REPLICATION_DONE; + s->error = 0; + } else { + backup_job_cleanup(s); + } } static bool check_top_bs(BlockDriverState *top_bs, BlockDriverState *bs) @@ -450,6 +454,15 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, switch (s->mode) { case REPLICATION_MODE_PRIMARY: + if (s->is_shared_disk) { + backup_start("replication-backup", s->primary_disk->bs, bs, 0, + MIRROR_SYNC_MODE_NONE, NULL, false, BLOCKDEV_ON_ERROR_REPORT, + BLOCKDEV_ON_ERROR_REPORT, backup_job_completed, + s, NULL, &local_err); + if (local_err) { + error_propagate(errp, local_err); + } + } break; case REPLICATION_MODE_SECONDARY: s->active_disk = bs->file; @@ -468,7 +481,8 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, } s->secondary_disk = s->hidden_disk->bs->backing; - if (!s->secondary_disk->bs || !bdrv_has_blk(s->secondary_disk->bs)) { + if (!s->secondary_disk->bs || + (!s->is_shared_disk && !bdrv_has_blk(s->secondary_disk->bs))) { error_setg(errp, "The secondary disk doesn't have block backend"); aio_context_release(aio_context); return; @@ -560,11 +574,24 @@ static void replication_do_checkpoint(ReplicationState *rs, Error **errp) switch (s->mode) { case REPLICATION_MODE_PRIMARY: + if (s->is_shared_disk) { + if (!s->primary_disk->bs->job) { + error_setg(errp, "Primary backup job was cancelled" + " unexpectedly"); + break; + } + + backup_do_checkpoint(s->primary_disk->bs->job, &local_err); + if (local_err) { + error_propagate(errp, local_err); + } + } break; case REPLICATION_MODE_SECONDARY: if (!s->is_shared_disk) { if (!s->secondary_disk->bs->job) { - error_setg(errp, "Backup job was cancelled unexpectedly"); + error_setg(errp, "Secondary backup job was cancelled" + " unexpectedly"); break; } backup_do_checkpoint(s->secondary_disk->bs->job, &local_err); @@ -643,8 +670,12 @@ static void replication_stop(ReplicationState *rs, bool failover, Error **errp) switch (s->mode) { case REPLICATION_MODE_PRIMARY: - s->replication_state = BLOCK_REPLICATION_DONE; - s->error = 0; + if (s->is_shared_disk && s->primary_disk->bs->job) { + block_job_cancel(s->primary_disk->bs->job); + } else { + s->replication_state = BLOCK_REPLICATION_DONE; + s->error = 0; + } break; case REPLICATION_MODE_SECONDARY: /*