From e4ea6918c93b9f59d34e8ca2124b2b64b1afe73b Mon Sep 17 00:00:00 2001 From: Aaro Koskinen Date: Tue, 7 Aug 2012 14:39:25 +0200 Subject: [PATCH] ARM: dma-mapping: fix atomic allocation alignment The alignment mask is calculated incorrectly. Fixing the calculation makes strange hangs/lockups disappear during the boot with Amstrad E3 and 3.6-rc1 kernel. Signed-off-by: Aaro Koskinen Signed-off-by: Marek Szyprowski --- arch/arm/mm/dma-mapping.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 334dd79ad5e6..4bdeccd24d93 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -423,7 +423,7 @@ static void *__alloc_from_pool(size_t size, struct page **ret_page) unsigned int pageno; unsigned long flags; void *ptr = NULL; - size_t align; + unsigned long align_mask; if (!pool->vaddr) { WARN(1, "coherent pool not initialised!\n"); @@ -435,11 +435,11 @@ static void *__alloc_from_pool(size_t size, struct page **ret_page) * small, so align them to their order in pages, minimum is a page * size. This helps reduce fragmentation of the DMA space. */ - align = PAGE_SIZE << get_order(size); + align_mask = (1 << get_order(size)) - 1; spin_lock_irqsave(&pool->lock, flags); pageno = bitmap_find_next_zero_area(pool->bitmap, pool->nr_pages, - 0, count, (1 << align) - 1); + 0, count, align_mask); if (pageno < pool->nr_pages) { bitmap_set(pool->bitmap, pageno, count); ptr = pool->vaddr + PAGE_SIZE * pageno;