Commit 8be25de6 authored by Kevin Wolf's avatar Kevin Wolf
Browse files

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: default avatarKevin Wolf <kwolf@redhat.com>
Reviewed-by: default avatarEric Blake <eblake@redhat.com>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent 1324f063

block.c

+13 −7
Original line number Diff line number Diff line
@@ -1438,14 +1438,20 @@ 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)) {

        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);

        ret = -ENOTSUP;

            goto fail_opts;

        }

    }



    /* bdrv_new() and bdrv_close() make it so */

    assert(atomic_read(&bs->copy_on_read) == 0);