block: Apply auto-read-only for ro-whitelist drivers
If QEMU was configured with a driver in --block-drv-ro-whitelist, trying
to use that driver read-write resulted in an error message even if
auto-read-only=on was set.
Consider auto-read-only=on for the whitelist checking and use it to
automatically degrade to read-only for block drivers on the read-only
whitelist.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/block.c b/block.c
index 0c5d1f1..5a4d271 100644
--- a/block.c
+++ b/block.c
@@ -1438,13 +1438,19 @@
bs->read_only = !(bs->open_flags & BDRV_O_RDWR);
if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) {
- error_setg(errp,
- !bs->read_only && bdrv_is_whitelisted(drv, true)
- ? "Driver '%s' can only be used for read-only devices"
- : "Driver '%s' is not whitelisted",
- drv->format_name);
- ret = -ENOTSUP;
- goto fail_opts;
+ if (!bs->read_only && bdrv_is_whitelisted(drv, true)) {
+ ret = bdrv_apply_auto_read_only(bs, NULL, NULL);
+ } else {
+ ret = -ENOTSUP;
+ }
+ if (ret < 0) {
+ error_setg(errp,
+ !bs->read_only && bdrv_is_whitelisted(drv, true)
+ ? "Driver '%s' can only be used for read-only devices"
+ : "Driver '%s' is not whitelisted",
+ drv->format_name);
+ goto fail_opts;
+ }
}
/* bdrv_new() and bdrv_close() make it so */
