On 10/26/2012 10:06 AM, Shuah Khan wrote:
On Fri, 2012-10-26 at 09:45 -0700, David Daney wrote:
On 10/26/2012 09:01 AM, Shuah Khan wrote:
Add support for debug_dma_mapping_error() call to avoid warning from
debug_dma_unmap() interface when it checks for mapping error checked
status. Without this patch, device driver failed to check map error
warning is generated.
Signed-off-by: Shuah Khan <shuah.khan@xxxxxx>
---
arch/mips/include/asm/dma-mapping.h | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/mips/include/asm/dma-mapping.h b/arch/mips/include/asm/dma-mapping.h
index be39a12..006b43e 100644
--- a/arch/mips/include/asm/dma-mapping.h
+++ b/arch/mips/include/asm/dma-mapping.h
@@ -40,6 +40,8 @@ static inline int dma_supported(struct device *dev, u64 mask)
static inline int dma_mapping_error(struct device *dev, u64 mask)
{
struct dma_map_ops *ops = get_dma_ops(dev);
+
+ debug_dma_mapping_error(dev, mask);
return ops->mapping_error(dev, mask);
}
Although this is a start, I don't think it is sufficient.
As far as I can tell, there are many missing calls to debug_dma_*() in
the various MIPS commone and sub-architecture DMA code.
Really you (or someone) needs to look at *all* the functions in
arch/mips/asm/dma-mapping.h, and arch/mips/mm/dma-default.c and find
places missing a debug_dma_*().
Is it correct to assume that this patch is not needed on MIPS until
debug_dma interfaces get added to MIPS common and sub-architecture DMA
code.
No, you have a false predicate here.
debug_dma_* *is* already mostly added. The problem is that it is
incomplete. That is the nature of the problem. Your patch makes it
slightly better, but doesn't fully fix the problems.
When I didn't see dma_map_page() in arch/mips/include/asm/dma-mapping.h
defined, and just an extern, I incorrectly assumed, it is getting picked
up from <asm-generic/dma-mapping-common.h>, hence the need for this
patch in the first place.
-- Shuah
