static void parse_drive(DeviceState *dev, const char *str, void **ptr, const char *propname, Error **errp) { BlockBackend *blk; blk = blk_by_name(str); if (!blk) { error_setg(errp, "Property '%s.%s' can't find value '%s'", object_get_typename(OBJECT(dev)), propname, str); return; } if (blk_attach_dev(blk, dev) < 0) { DriveInfo *dinfo = blk_legacy_dinfo(blk); if (dinfo && dinfo->type != IF_NONE) { error_setg(errp, "Drive '%s' is already in use because " "it has been automatically connected to another " "device (did you need 'if=none' in the drive options?)", str); } else { error_setg(errp, "Drive '%s' is already in use by another device", str); } return; } *ptr = blk; }