From patchwork Wed Nov 19 14:19:44 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 412414 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4834D140172 for ; Thu, 20 Nov 2014 01:23:02 +1100 (AEDT) Received: from localhost ([::1]:58664 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xr69s-0004wy-4F for incoming@patchwork.ozlabs.org; Wed, 19 Nov 2014 09:23:00 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57534) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xr672-0000DB-A6 for qemu-devel@nongnu.org; Wed, 19 Nov 2014 09:20:10 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Xr66w-0003sn-0y for qemu-devel@nongnu.org; Wed, 19 Nov 2014 09:20:04 -0500 Received: from mx1.redhat.com ([209.132.183.28]:33266) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xr66v-0003sU-QY for qemu-devel@nongnu.org; Wed, 19 Nov 2014 09:19:57 -0500 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 (8.14.4/8.14.4) with ESMTP id sAJEJuLA004625 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Wed, 19 Nov 2014 09:19:57 -0500 Received: from localhost (ovpn-112-54.ams2.redhat.com [10.36.112.54]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id sAJEJtmb018787; Wed, 19 Nov 2014 09:19:55 -0500 From: Stefan Hajnoczi To: Date: Wed, 19 Nov 2014 14:19:44 +0000 Message-Id: <1416406785-14241-4-git-send-email-stefanha@redhat.com> In-Reply-To: <1416406785-14241-1-git-send-email-stefanha@redhat.com> References: <1416406785-14241-1-git-send-email-stefanha@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: Kevin Wolf , Stefan Hajnoczi , mreitz@redhat.com Subject: [Qemu-devel] [PATCH for-2.3 3/4] blockdev: acquire AioContext in eject, change, and block_passwd 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 By acquiring the AioContext we avoid race conditions with the dataplane thread which may also be accessing the BlockDriverState. Fix up eject, change, and block_passwd in a single patch because qmp_eject() and qmp_change_blockdev() both call eject_device(). Also fix block_passwd while we're tackling a command that takes a block encryption password. Signed-off-by: Stefan Hajnoczi Reviewed-by: Max Reitz --- blockdev.c | 36 +++++++++++++++++++++++++++++------- hw/block/dataplane/virtio-blk.c | 1 + 2 files changed, 30 insertions(+), 7 deletions(-) diff --git a/blockdev.c b/blockdev.c index a7f1e09..7bf88d4 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1617,14 +1617,18 @@ exit: static void eject_device(BlockBackend *blk, int force, Error **errp) { BlockDriverState *bs = blk_bs(blk); + AioContext *aio_context; + + aio_context = bdrv_get_aio_context(bs); + aio_context_acquire(aio_context); if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) { - return; + goto out; } if (!blk_dev_has_removable_media(blk)) { error_setg(errp, "Device '%s' is not removable", bdrv_get_device_name(bs)); - return; + goto out; } if (blk_dev_is_medium_locked(blk) && !blk_dev_is_tray_open(blk)) { @@ -1632,11 +1636,14 @@ static void eject_device(BlockBackend *blk, int force, Error **errp) if (!force) { error_setg(errp, "Device '%s' is locked", bdrv_get_device_name(bs)); - return; + goto out; } } bdrv_close(bs); + +out: + aio_context_release(aio_context); } void qmp_eject(const char *device, bool has_force, bool force, Error **errp) @@ -1658,6 +1665,7 @@ void qmp_block_passwd(bool has_device, const char *device, { Error *local_err = NULL; BlockDriverState *bs; + AioContext *aio_context; int err; bs = bdrv_lookup_bs(has_device ? device : NULL, @@ -1668,16 +1676,23 @@ void qmp_block_passwd(bool has_device, const char *device, return; } + aio_context = bdrv_get_aio_context(bs); + aio_context_acquire(aio_context); + err = bdrv_set_key(bs, password); if (err == -EINVAL) { error_set(errp, QERR_DEVICE_NOT_ENCRYPTED, bdrv_get_device_name(bs)); - return; + goto out; } else if (err < 0) { error_set(errp, QERR_INVALID_PASSWORD); - return; + goto out; } + +out: + aio_context_release(aio_context); } +/* Assumes AioContext is held */ static void qmp_bdrv_open_encrypted(BlockDriverState *bs, const char *filename, int bdrv_flags, BlockDriver *drv, const char *password, Error **errp) @@ -1710,6 +1725,7 @@ void qmp_change_blockdev(const char *device, const char *filename, { BlockBackend *blk; BlockDriverState *bs; + AioContext *aio_context; BlockDriver *drv = NULL; int bdrv_flags; Error *err = NULL; @@ -1721,24 +1737,30 @@ void qmp_change_blockdev(const char *device, const char *filename, } bs = blk_bs(blk); + aio_context = bdrv_get_aio_context(bs); + aio_context_acquire(aio_context); + if (format) { drv = bdrv_find_whitelisted_format(format, bs->read_only); if (!drv) { error_set(errp, QERR_INVALID_BLOCK_FORMAT, format); - return; + goto out; } } eject_device(blk, 0, &err); if (err) { error_propagate(errp, err); - return; + goto out; } bdrv_flags = bdrv_is_read_only(bs) ? 0 : BDRV_O_RDWR; bdrv_flags |= bdrv_is_snapshot(bs) ? BDRV_O_SNAPSHOT : 0; qmp_bdrv_open_encrypted(bs, filename, bdrv_flags, drv, NULL, errp); + +out: + aio_context_release(aio_context); } /* throttling disk I/O limits */ diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c index 5ab64c5..2548113 100644 --- a/hw/block/dataplane/virtio-blk.c +++ b/hw/block/dataplane/virtio-blk.c @@ -198,6 +198,7 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *conf, blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_DRIVE_DEL, s->blocker); blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_BACKUP_SOURCE, s->blocker); blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_COMMIT, s->blocker); + blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_EJECT, s->blocker); blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, s->blocker); blk_op_unblock(conf->conf.blk, BLOCK_OP_TYPE_MIRROR, s->blocker);