DMA-API: Change dma_declare_coherent_memory() CPU address to phys_addr_t

dma_declare_coherent_memory() takes two addresses for a region of memory: a
"bus_addr" and a "device_addr".  I think the intent is that "bus_addr" is
the physical address a *CPU* would use to access the region, and
"device_addr" is the bus address the *device* would use to address the
region.

Rename "bus_addr" to "phys_addr" and change its type to phys_addr_t.
Most callers already supply a phys_addr_t for this argument.  The others
supply a 32-bit integer (a constant, unsigned int, or __u32) and need no
change.

Use "unsigned long", not phys_addr_t, to hold PFNs.

No functional change (this could theoretically fix a truncation in a config
with 32-bit dma_addr_t and 64-bit phys_addr_t, but I don't think there are
any such cases involving this code).

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: James Bottomley <jbottomley@Parallels.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>

2 files changed, 9 insertions, 11 deletions

diff --git a/include/asm-generic/dma-coherent.h b/include/asm-generic/dma-coherent.h
index 2be8a2dbc868..0297e5875798 100644
--- a/include/asm-generic/dma-coherent.h
+++ b/include/asm-generic/dma-coherent.h
@@ -16,16 +16,13 @@ int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma,
  * Standard interface
  */
 #define ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
-extern int
-dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
-			    dma_addr_t device_addr, size_t size, int flags);
+int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
+				dma_addr_t device_addr, size_t size, int flags);
 
-extern void
-dma_release_declared_memory(struct device *dev);
+void dma_release_declared_memory(struct device *dev);
 
-extern void *
-dma_mark_declared_memory_occupied(struct device *dev,
-				  dma_addr_t device_addr, size_t size);
+void *dma_mark_declared_memory_occupied(struct device *dev,
+					dma_addr_t device_addr, size_t size);
 #else
 #define dma_alloc_from_coherent(dev, size, handle, ret) (0)
 #define dma_release_from_coherent(dev, order, vaddr) (0)
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index b9aa2b97aab5..0c3eab1e39ac 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -192,7 +192,7 @@ static inline int dma_get_cache_alignment(void)
 
 #ifndef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
 static inline int
-dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
 			    dma_addr_t device_addr, size_t size, int flags)
 {
 	return 0;
@@ -223,13 +223,14 @@ extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
 extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
 				  dma_addr_t dma_handle);
 #ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
-extern int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+extern int dmam_declare_coherent_memory(struct device *dev,
+					phys_addr_t phys_addr,
 					dma_addr_t device_addr, size_t size,
 					int flags);
 extern void dmam_release_declared_memory(struct device *dev);
 #else /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
 static inline int dmam_declare_coherent_memory(struct device *dev,
-				dma_addr_t bus_addr, dma_addr_t device_addr,
+				phys_addr_t phys_addr, dma_addr_t device_addr,
 				size_t size, gfp_t gfp)
 {
 	return 0;