From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752895AbYIBPyO (ORCPT ); Tue, 2 Sep 2008 11:54:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751267AbYIBPx7 (ORCPT ); Tue, 2 Sep 2008 11:53:59 -0400 Received: from qb-out-0506.google.com ([72.14.204.238]:37920 "EHLO qb-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751211AbYIBPx6 (ORCPT ); Tue, 2 Sep 2008 11:53:58 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding :sender; b=vrSO+Z4IsM7GLPdlYb0Ggt0lvHX9TUlSgHUQuZ5Xnk8dU3cWutUpstywKzT0p+cfTC DbDQOYJaOtx6vZaq5wwzN/e/+9VaJZqFYaAVOIOH+rMkNUPbUvxYwt+z8zFcK0xihKfU XHRRhRN7i5GQ2jehHuZZCLcxxPVsE+NYRHBMM= Message-ID: <48BD6190.7070006@panasas.com> Date: Tue, 02 Sep 2008 18:53:52 +0300 From: Boaz Harrosh User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Ingo Molnar , Rusty Russell , "David S. Miller" , Ivo van Doorn , "John W. Linville" CC: Alexey Dobriyan , Andrew Morton , Theodore Tso , Linus Torvalds , Jan Beulich , linux-kernel Subject: [PATCH 3/5 ver2] virtio: Fix non-const BUILD_BUG_ON usage References: <48BBE77D.7070007@panasas.com> <48BBEA82.4020903@panasas.com> In-Reply-To: <48BBEA82.4020903@panasas.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In virtio_has_feature() BUILD_BUG_ON can not be used cross inline parametrization boundary. I've put the BUILD_BUG_ON(_ZERO) in a macro outside of the inline definition. (So it is in the caller scope). However It is no longer legal to pass BUILD_BUG_ON a non-const expression so users like virtio_config_buf() should caller __virtio_has_feature() which does the actual code minus the check. Signed-off-by: Boaz Harrosh CC: Ingo Molnar CC: Rusty Russell --- include/linux/virtio_config.h | 13 +++++++------ 1 files changed, 7 insertions(+), 6 deletions(-) diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index bf8ec28..7accb1d 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -92,17 +92,18 @@ void virtio_check_driver_offered_feature(const struct virtio_device *vdev, * @vdev: the device * @fbit: the feature bit */ -static inline bool virtio_has_feature(const struct virtio_device *vdev, +static inline bool __virtio_has_feature(const struct virtio_device *vdev, unsigned int fbit) { - /* Did you forget to fix assumptions on max features? */ - if (__builtin_constant_p(fbit)) - BUILD_BUG_ON(fbit >= 32); - virtio_check_driver_offered_feature(vdev, fbit); return test_bit(fbit, vdev->features); } +/* Did you forget to fix assumptions on max features? */ +#define virtio_has_feature(vdev, fbit) \ + (BUILD_BUG_ON_ZERO(fbit >= 32) + __virtio_has_feature(vdev, fbit)) + + /** * virtio_config_val - look for a feature and get a virtio config entry. * @vdev: the virtio device @@ -120,7 +121,7 @@ static inline int virtio_config_buf(struct virtio_device *vdev, unsigned int offset, void *buf, unsigned len) { - if (!virtio_has_feature(vdev, fbit)) + if (!__virtio_has_feature(vdev, fbit)) return -ENOENT; vdev->config->get(vdev, offset, buf, len); -- 1.5.6.rc1.5.gadf6