| Message ID | 20190122121926.25554-1-kwolf@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | block: Apply auto-read-only for ro-whitelist drivers | expand |
On 1/22/19 6:19 AM, Kevin Wolf wrote: > 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> > --- > block.c | 20 +++++++++++++------- > 1 file changed, 13 insertions(+), 7 deletions(-) > Reviewed-by: Eric Blake <eblake@redhat.com>
On Tue, Jan 22, 2019 at 01:19:26PM +0100, Kevin Wolf wrote: > 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> > --- > block.c | 20 +++++++++++++------- > 1 file changed, 13 insertions(+), 7 deletions(-) Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/block.c b/block.c index 92a3b45a78..0eba8ebe5c 100644 --- a/block.c +++ b/block.c @@ -1438,13 +1438,19 @@ static int bdrv_open_common(BlockDriverState *bs, BlockBackend *file, 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 */
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> --- block.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-)