From nobody Mon Feb 9 04:59:38 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1489625235908953.0053408327773; Wed, 15 Mar 2017 17:47:15 -0700 (PDT) Received: from localhost ([::1]:40164 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1coJZR-00035H-84 for importer@patchew.org; Wed, 15 Mar 2017 20:47:13 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46580) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1coJYS-0002zT-R5 for qemu-devel@nongnu.org; Wed, 15 Mar 2017 20:46:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1coJYR-0004W2-QK for qemu-devel@nongnu.org; Wed, 15 Mar 2017 20:46:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53134) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1coJYP-0004TW-4S; Wed, 15 Mar 2017 20:46:09 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 193DC80F8E; Thu, 16 Mar 2017 00:46:09 +0000 (UTC) Received: from scv.usersys.redhat.com (dhcp-17-221.bos.redhat.com [10.18.17.221]) by smtp.corp.redhat.com (Postfix) with ESMTP id 768E360F88; Thu, 16 Mar 2017 00:46:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 193DC80F8E Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=jsnow@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 193DC80F8E From: John Snow To: qemu-block@nongnu.org Date: Wed, 15 Mar 2017 20:46:03 -0400 Message-Id: <20170316004603.20609-4-jsnow@redhat.com> In-Reply-To: <20170316004603.20609-1-jsnow@redhat.com> References: <20170316004603.20609-1-jsnow@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Thu, 16 Mar 2017 00:46:09 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [RFC patch 3/3] blockjob: add devops to blockjob backends 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, pbonzini@redhat.com, John Snow , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" This lets us hook into drained_begin and drained_end requests from the backend level, which is particularly useful for making sure that all jobs associated with a particular node (whether the source or the target) receive a drain request. Suggested-by: Kevin Wolf Signed-off-by: John Snow -- RFC topics: - BlkDevOps is traditionally only for Qdev devices, and a BlockJob is not currently a 'device'... Do we want to loosen this restriction, find anoth= er way to deliver callbacks to BlockJobs attached to BlkBackends, or do some= thing crazy like make a BlockJob device object? struct JobDevice { DeviceState parent_obj; BlockJob *job; } ...?? - Not so sure about leaving the initial job refcount at 1, since we are giv= ing away a handle to this job as dev_opaque. By incrementing it to 2, however, it's not clear whose responsibility it is to decrement it again. Signed-off-by: John Snow --- blockjob.c | 34 +++++++++++++++++++++++++++++----- 1 file changed, 29 insertions(+), 5 deletions(-) diff --git a/blockjob.c b/blockjob.c index 6d08ce5..0542677 100644 --- a/blockjob.c +++ b/blockjob.c @@ -68,6 +68,23 @@ static const BdrvChildRole child_job =3D { .stay_at_node =3D true, }; =20 +static void block_job_drained_begin(void *opaque) +{ + BlockJob *job =3D opaque; + block_job_pause(job); +} + +static void block_job_drained_end(void *opaque) +{ + BlockJob *job =3D opaque; + block_job_resume(job); +} + +static const BlockDevOps block_job_dev_ops =3D { + .drained_begin =3D block_job_drained_begin, + .drained_end =3D block_job_drained_end, +}; + BlockJob *block_job_next(BlockJob *job) { if (!job) { @@ -205,11 +222,6 @@ void *block_job_create(const char *job_id, const Block= JobDriver *driver, } =20 job =3D g_malloc0(driver->instance_size); - error_setg(&job->blocker, "block device is in use by block job: %s", - BlockJobType_lookup[driver->job_type]); - block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort= ); - bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker); - job->driver =3D driver; job->id =3D g_strdup(job_id); job->blk =3D blk; @@ -219,8 +231,20 @@ void *block_job_create(const char *job_id, const Block= JobDriver *driver, job->paused =3D true; job->pause_count =3D 1; job->refcnt =3D 1; + /* RFC: job is now stored both in bs->job and blk->dev_opaque, + * but we cannot expect the backend to know how to put down the ref + * so it'd be up to this code here to increment it anyway, making it + * a bit of a useless exercise. It would be up to us to ensure that + * we destruct the blkbackend before putting down our last reference. = */ + + error_setg(&job->blocker, "block device is in use by block job: %s", + BlockJobType_lookup[driver->job_type]); + block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort= ); bs->job =3D job; =20 + blk_set_dev_ops(blk, &block_job_dev_ops, job); + bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker); + QLIST_INSERT_HEAD(&block_jobs, job, job_list); =20 blk_add_aio_context_notifier(blk, block_job_attached_aio_context, --=20 2.9.3