From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
To: Max Reitz <mreitz@redhat.com>,
"qemu-block@nongnu.org" <qemu-block@nongnu.org>
Cc: Kevin Wolf <kwolf@redhat.com>, Alberto Garcia <berto@igalia.com>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>
Subject: Re: [PATCH for-5.0 v2 11/23] block: Use bdrv_recurse_can_replace()
Date: Fri, 29 Nov 2019 11:07:23 +0000 [thread overview]
Message-ID: <81e6ac08-2f89-9606-0642-4f4f92aeba2e@virtuozzo.com> (raw)
In-Reply-To: <20191111160216.197086-12-mreitz@redhat.com>
11.11.2019 19:02, Max Reitz wrote:
> Let check_to_replace_node() use the more specialized
> bdrv_recurse_can_replace() instead of
> bdrv_recurse_is_first_non_filter(), which is too restrictive.
or not enough restrictive in case of quorum
>
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
> block.c | 18 ++++++++++++++++--
> 1 file changed, 16 insertions(+), 2 deletions(-)
>
> diff --git a/block.c b/block.c
> index de53addeb0..7608f21570 100644
> --- a/block.c
> +++ b/block.c
> @@ -6243,6 +6243,17 @@ bool bdrv_recurse_can_replace(BlockDriverState *bs,
> return false;
> }
>
> +/*
> + * Check whether the given @node_name can be replaced by a node that
> + * has the same data as @parent_bs. If so, return @node_name's BDS;
> + * NULL otherwise.
> + *
> + * @node_name must be a (recursive) *child of @parent_bs (or this
> + * function will return NULL).
> + *
> + * The result (whether the node can be replaced or not) is only valid
> + * for as long as no graph changes occur.
actually, no graph changes neither any permission changes or updates.
> + */
> BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs,
> const char *node_name, Error **errp)
> {
> @@ -6267,8 +6278,11 @@ BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs,
> * Another benefit is that this tests exclude backing files which are
> * blocked by the backing blockers.
> */
> - if (!bdrv_recurse_is_first_non_filter(parent_bs, to_replace_bs)) {
> - error_setg(errp, "Only top most non filter can be replaced");
> + if (!bdrv_recurse_can_replace(parent_bs, to_replace_bs)) {
> + error_setg(errp, "Cannot replace '%s' by a node mirrored from '%s', "
> + "because it cannot be guaranteed that doing so would not "
> + "lead to an abrupt change of visible data",
> + node_name, parent_bs->node_name);
> to_replace_bs = NULL;
> goto out;
> }
>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
--
Best regards,
Vladimir
next prev parent reply other threads:[~2019-11-29 11:17 UTC|newest]
Thread overview: 75+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-11 16:01 [PATCH for-5.0 v2 00/23] block: Fix check_to_replace_node() Max Reitz
2019-11-11 16:01 ` [PATCH for-5.0 v2 01/23] blockdev: Allow external snapshots everywhere Max Reitz
2019-11-11 16:01 ` [PATCH for-5.0 v2 02/23] blockdev: Allow resizing everywhere Max Reitz
2019-12-06 14:04 ` Alberto Garcia
2019-12-09 13:56 ` Max Reitz
2019-11-11 16:01 ` [PATCH for-5.0 v2 03/23] block: Drop bdrv_is_first_non_filter() Max Reitz
2019-11-11 16:01 ` [PATCH for-5.0 v2 04/23] iotests: Let 041 use -blockdev for quorum children Max Reitz
2019-11-11 16:01 ` [PATCH for-5.0 v2 05/23] quorum: Fix child permissions Max Reitz
2019-11-29 9:14 ` Vladimir Sementsov-Ogievskiy
2019-11-11 16:01 ` [PATCH for-5.0 v2 06/23] block: Add bdrv_recurse_can_replace() Max Reitz
2019-11-29 9:34 ` Vladimir Sementsov-Ogievskiy
2019-11-29 10:23 ` Max Reitz
2019-11-29 11:04 ` Vladimir Sementsov-Ogievskiy
2019-11-11 16:02 ` [PATCH for-5.0 v2 07/23] blkverify: Implement .bdrv_recurse_can_replace() Max Reitz
2019-11-29 9:41 ` Vladimir Sementsov-Ogievskiy
2019-11-11 16:02 ` [PATCH for-5.0 v2 08/23] quorum: Store children in own structure Max Reitz
2019-11-29 9:46 ` Vladimir Sementsov-Ogievskiy
2019-11-11 16:02 ` [PATCH for-5.0 v2 09/23] quorum: Add QuorumChild.to_be_replaced Max Reitz
2019-11-29 9:59 ` Vladimir Sementsov-Ogievskiy
2019-11-11 16:02 ` [PATCH for-5.0 v2 10/23] quorum: Implement .bdrv_recurse_can_replace() Max Reitz
2019-11-29 10:18 ` Vladimir Sementsov-Ogievskiy
2019-11-29 12:50 ` Max Reitz
2020-02-05 15:55 ` Kevin Wolf
2020-02-05 16:03 ` Kevin Wolf
2020-02-06 10:21 ` Max Reitz
2020-02-06 14:42 ` Kevin Wolf
2020-02-06 15:19 ` Max Reitz
2020-02-06 15:42 ` Kevin Wolf
2020-02-06 16:44 ` Max Reitz
2019-11-11 16:02 ` [PATCH for-5.0 v2 11/23] block: Use bdrv_recurse_can_replace() Max Reitz
2019-11-29 11:07 ` Vladimir Sementsov-Ogievskiy [this message]
2020-02-05 15:57 ` Kevin Wolf
2019-11-11 16:02 ` [PATCH for-5.0 v2 12/23] block: Remove bdrv_recurse_is_first_non_filter() Max Reitz
2019-11-11 16:02 ` [PATCH for-5.0 v2 13/23] mirror: Double-check immediately before replacing Max Reitz
2019-11-29 11:18 ` Vladimir Sementsov-Ogievskiy
2019-11-11 16:02 ` [PATCH for-5.0 v2 14/23] quorum: Stop marking it as a filter Max Reitz
2019-11-11 16:02 ` [PATCH for-5.0 v2 15/23] mirror: Prevent loops Max Reitz
2019-11-29 12:01 ` Vladimir Sementsov-Ogievskiy
2019-11-29 13:46 ` Max Reitz
2019-11-29 13:55 ` Vladimir Sementsov-Ogievskiy
2019-11-29 14:17 ` Max Reitz
2019-11-29 14:26 ` Vladimir Sementsov-Ogievskiy
2019-11-29 14:38 ` Max Reitz
2019-12-02 12:12 ` Vladimir Sementsov-Ogievskiy
2019-12-09 14:43 ` Max Reitz
2019-12-13 11:18 ` Vladimir Sementsov-Ogievskiy
2019-12-20 11:39 ` Max Reitz
2019-12-20 11:55 ` Vladimir Sementsov-Ogievskiy
2019-12-20 12:10 ` Max Reitz
2019-11-11 16:02 ` [PATCH for-5.0 v2 16/23] iotests: Use complete_and_wait() in 155 Max Reitz
2019-11-11 16:02 ` [PATCH for-5.0 v2 17/23] iotests: Use skip_if_unsupported decorator in 041 Max Reitz
2019-12-03 12:03 ` Vladimir Sementsov-Ogievskiy
2019-11-11 16:02 ` [PATCH for-5.0 v2 18/23] iotests: Add VM.assert_block_path() Max Reitz
2019-12-03 12:59 ` Vladimir Sementsov-Ogievskiy
2019-12-09 15:10 ` Max Reitz
2019-12-13 11:26 ` Vladimir Sementsov-Ogievskiy
2019-12-13 11:27 ` Vladimir Sementsov-Ogievskiy
2019-12-20 11:42 ` Max Reitz
2019-11-11 16:02 ` [PATCH for-5.0 v2 19/23] iotests: Resolve TODOs in 041 Max Reitz
2019-12-03 13:32 ` Vladimir Sementsov-Ogievskiy
2019-12-03 13:33 ` Vladimir Sementsov-Ogievskiy
2019-12-09 15:15 ` Max Reitz
2019-12-13 11:31 ` Vladimir Sementsov-Ogievskiy
2019-11-11 16:02 ` [PATCH for-5.0 v2 20/23] iotests: Use self.image_len in TestRepairQuorum Max Reitz
2019-11-11 16:02 ` [PATCH for-5.0 v2 21/23] iotests: Add tests for invalid Quorum @replaces Max Reitz
2019-12-03 14:40 ` Vladimir Sementsov-Ogievskiy
2019-11-11 16:02 ` [PATCH for-5.0 v2 22/23] iotests: Check that @replaces can replace filters Max Reitz
2019-12-03 15:58 ` Vladimir Sementsov-Ogievskiy
2019-12-09 15:17 ` Max Reitz
2019-11-11 16:02 ` [PATCH for-5.0 v2 23/23] iotests: Mirror must not attempt to create loops Max Reitz
2019-12-03 17:03 ` Vladimir Sementsov-Ogievskiy
2019-11-29 12:24 ` [PATCH for-5.0 v2 00/23] block: Fix check_to_replace_node() Vladimir Sementsov-Ogievskiy
2019-11-29 12:49 ` Max Reitz
2019-11-29 12:55 ` Vladimir Sementsov-Ogievskiy
2019-11-29 13:08 ` Max Reitz
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