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>
This commit is contained in:
Bjorn Helgaas
2014-05-20 16:54:22 -06:00
parent 77f2ea2f8d
commit 88a984ba07
5 changed files with 21 additions and 24 deletions

View File

@@ -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;