[PATCH] mm: split highorder pages

Have an explicit mm call to split higher order pages into individual pages.
 Should help to avoid bugs and be more explicit about the code's intention.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/arch/arm/mm/consistent.c b/arch/arm/mm/consistent.c
index c2ee18d2075e..8a1bfcd50087 100644
--- a/arch/arm/mm/consistent.c
+++ b/arch/arm/mm/consistent.c
@@ -223,6 +223,8 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
                 pte = consistent_pte[idx] + off;
                 c->vm_pages = page;
 
+                split_page(page, order);
+
                 /*
                  * Set the "dma handle"
                  */
@@ -231,7 +233,6 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
                 do {
                         BUG_ON(!pte_none(*pte));
 
-                        set_page_count(page, 1);
                         /*
                          * x86 does not mark the pages reserved...
                          */
@@ -250,7 +251,6 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
                  * Free the otherwise unused pages.
                  */
                 while (page < end) {
-                        set_page_count(page, 1);
                         __free_page(page);
                         page++;
                 }