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 <bharrosh@panasas.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Rusty Russell <rusty@rustcorp.com.au>
---
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
--
