dma-mapping: rename ARCH_KMALLOC_MINALIGN to ARCH_DMA_MINALIGN

Now each architecture has the own dma_get_cache_alignment implementation.

dma_get_cache_alignment returns the minimum DMA alignment.  Architectures
define it as ARCH_KMALLOC_MINALIGN (it's used to make sure that malloc'ed
buffer is DMA-safe; the buffer doesn't share a cache with the others).  So
we can unify dma_get_cache_alignment implementations.

This patch:

dma_get_cache_alignment() needs to know if an architecture defines
ARCH_KMALLOC_MINALIGN or not (needs to know if architecture has DMA
alignment restriction).  However, slab.h define ARCH_KMALLOC_MINALIGN if
architectures doesn't define it.

Let's rename ARCH_KMALLOC_MINALIGN to ARCH_DMA_MINALIGN.
ARCH_KMALLOC_MINALIGN is used only in the internals of slab/slob/slub
(except for crypto).

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>

3 files changed, 11 insertions, 5 deletions

diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h
index 1acfa73ce2ac..791a502f6906 100644
--- a/include/linux/slab_def.h
+++ b/include/linux/slab_def.h
@@ -17,7 +17,6 @@
 
 #include <trace/events/kmem.h>
 
-#ifndef ARCH_KMALLOC_MINALIGN
 /*
  * Enforce a minimum alignment for the kmalloc caches.
  * Usually, the kmalloc caches are cache_line_size() aligned, except when
@@ -27,6 +26,9 @@
  * ARCH_KMALLOC_MINALIGN allows that.
  * Note that increasing this value may disable some debug features.
  */
+#ifdef ARCH_DMA_MINALIGN
+#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
+#else
 #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
 #endif
 
diff --git a/include/linux/slob_def.h b/include/linux/slob_def.h
index 62667f72c2ef..4382db09df4f 100644
--- a/include/linux/slob_def.h
+++ b/include/linux/slob_def.h
@@ -1,7 +1,9 @@
 #ifndef __LINUX_SLOB_DEF_H
 #define __LINUX_SLOB_DEF_H
 
-#ifndef ARCH_KMALLOC_MINALIGN
+#ifdef ARCH_DMA_MINALIGN
+#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
+#else
 #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long)
 #endif
 
diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index 6447a723ecb1..6d14409c4d9a 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -106,15 +106,17 @@ struct kmem_cache {
 /*
  * Kmalloc subsystem.
  */
-#if defined(ARCH_KMALLOC_MINALIGN) && ARCH_KMALLOC_MINALIGN > 8
-#define KMALLOC_MIN_SIZE ARCH_KMALLOC_MINALIGN
+#if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8
+#define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN
 #else
 #define KMALLOC_MIN_SIZE 8
 #endif
 
 #define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
 
-#ifndef ARCH_KMALLOC_MINALIGN
+#ifdef ARCH_DMA_MINALIGN
+#define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
+#else
 #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
 #endif