On 2020-09-15 11:09 a.m., Christoph Hellwig wrote:
On Tue, Sep 15, 2020 at 10:40:39AM -0400, Thomas Tai wrote:
+++ b/include/linux/dma-direct.h
@@ -62,9 +62,6 @@ static inline bool dma_capable(struct device *dev, dma_addr_t
addr, size_t size,
{
dma_addr_t end = addr + size - 1;
- if (!dev->dma_mask)
- return false;
-
I am concerned that some drivers may rely on this NULL checking. Would you
think we can keep this checking and use the following WARN_ON_ONCE()?
dma_capable is not a helper for drivers, but just for dma-direct
and related code. And this patch adds the checks for the three
places how we call into the ->map* methods.
Ok. That sounds good to me. I will make the suggested changes and run
some tests before sending out the V2 patch.
Thank you,
Thomas
