block: Fix reopen with semantically overlapping options

This fixes bdrv_reopen() calls like the following one:

    qemu-io -c 'open -o overlap-check.template=all /tmp/test.qcow2' \
    -c 'reopen -o overlap-check=none'

The approach taken so far would result in an options QDict that has both
"overlap-check.template=all" and "overlap-check=none", which obviously
conflicts. In this case, the old option should be overridden by the
newly specified option.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
This commit is contained in:
Kevin Wolf 2015-11-16 16:43:27 +01:00
parent 5365f44dfa
commit cddff5bae1

16
block.c
View File

@ -623,6 +623,20 @@ static int refresh_total_sectors(BlockDriverState *bs, int64_t hint)
return 0;
}
/**
* Combines a QDict of new block driver @options with any missing options taken
* from @old_options, so that leaving out an option defaults to its old value.
*/
static void bdrv_join_options(BlockDriverState *bs, QDict *options,
QDict *old_options)
{
if (bs->drv && bs->drv->bdrv_join_options) {
bs->drv->bdrv_join_options(options, old_options);
} else {
qdict_join(options, old_options, false);
}
}
/**
* Set open flags for a given discard mode
*
@ -1663,7 +1677,7 @@ BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
}
old_options = qdict_clone_shallow(bs->options);
qdict_join(options, old_options, false);
bdrv_join_options(bs, options, old_options);
QDECREF(old_options);
/* bdrv_open() masks this flag out */