dma-mapping: unify dma_get_cache_alignment implementations

dma_get_cache_alignment returns the minimum DMA alignment.  Architectures
defines it as ARCH_DMA_MINALIGN (formally ARCH_KMALLOC_MINALIGN).  So we
can unify dma_get_cache_alignment implementations.

Note that some architectures implement dma_get_cache_alignment wrongly.
dma_get_cache_alignment() should return the minimum DMA alignment.  So
fully-coherent architectures should return 1.  This patch also fixes this
issue.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 0 insertions, 8 deletions

diff --git a/arch/ia64/include/asm/dma-mapping.h b/arch/ia64/include/asm/dma-mapping.h
index 7d09a09cdaad..8d52deed3750 100644
--- a/arch/ia64/include/asm/dma-mapping.h
+++ b/arch/ia64/include/asm/dma-mapping.h
@@ -86,8 +86,6 @@ static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
         return daddr;
 }
 
-extern int dma_get_cache_alignment(void);
-
 static inline void
 dma_cache_sync (struct device *dev, void *vaddr, size_t size,
         enum dma_data_direction dir)
diff --git a/arch/ia64/kernel/setup.c b/arch/ia64/kernel/setup.c
index 41ae6a596b50..8fb958abf8d0 100644
--- a/arch/ia64/kernel/setup.c
+++ b/arch/ia64/kernel/setup.c
@@ -98,12 +98,6 @@ static struct resource bss_resource = {
 
 unsigned long ia64_max_cacheline_size;
 
-int dma_get_cache_alignment(void)
-{
-        return ia64_max_cacheline_size;
-}
-EXPORT_SYMBOL(dma_get_cache_alignment);
-
 unsigned long ia64_iobase;      /* virtual address for I/O accesses */
 EXPORT_SYMBOL(ia64_iobase);
 struct io_space io_space[MAX_IO_SPACES];