Re: No dma_sync_* during pci_probe? (Sparc, post 2.6.22 regression)

David Miller
2007-12-20T08:40:52Z

From: Stefan Richter <stefanr@s5r6.in-berlin.de>
Date: Wed, 19 Dec 2007 17:33:05 +0100

> Does arch/sparc64/kernel/pci.c fill them in incorrectly or too late?

The problem is that I created indirection that was totally unused, the
operation vectors members for these cases thus didn't get filled in,
and we OOPS trying to call NULL pointers as functions :-)

This should fix the crash:

diff --git a/include/asm-sparc64/dma-mapping.h b/include/asm-sparc64/dma-mapping.h
index 1fc6554..38cbec7 100644
--- a/include/asm-sparc64/dma-mapping.h
+++ b/include/asm-sparc64/dma-mapping.h
@@ -25,15 +25,9 @@ struct dma_ops {
void (*sync_single_for_cpu)(struct device *dev,
dma_addr_t dma_handle, size_t size,
enum dma_data_direction direction);
- void (*sync_single_for_device)(struct device *dev,
- dma_addr_t dma_handle, size_t size,
- enum dma_data_direction direction);
void (*sync_sg_for_cpu)(struct device *dev, struct scatterlist *sg,
int nelems,
enum dma_data_direction direction);
- void (*sync_sg_for_device)(struct device *dev, struct scatterlist *sg,
- int nelems,
- enum dma_data_direction direction);
};
extern const struct dma_ops *dma_ops;

@@ -105,7 +99,7 @@ static inline void dma_sync_single_for_device(struct device *dev,
size_t size,
enum dma_data_direction direction)
{
- dma_ops->sync_single_for_device(dev, dma_handle, size, direction);
+ /* No flushing needed to sync cpu writes to the device. */
}

static inline void dma_sync_single_range_for_cpu(struct device *dev,
@@ -123,7 +117,7 @@ static inline void dma_sync_single_range_for_device(struct device *dev,
size_t size,
enum dma_data_direction direction)
{
- dma_sync_single_for_device(dev, dma_handle+offset, size, direction);
+ /* No flushing needed to sync cpu writes to the device. */
}

@@ -138,7 +132,7 @@ static inline void dma_sync_sg_for_device(struct device *dev,
struct scatterlist *sg, int nelems,
enum dma_data_direction direction)
{
- dma_ops->sync_sg_for_device(dev, sg, nelems, direction);
+ /* No flushing needed to sync cpu writes to the device. */
}

static inline int dma_mapping_error(dma_addr_t dma_addr)