From b8b14c66765ccba884c5c4570bf8be361d211d95 Mon Sep 17 00:00:00 2001 From: Kumar Gala Date: Mon, 3 May 2010 07:36:22 -0500 Subject: [PATCH] powerpc/swiotlb: Fix off by one in determining boundary of which ops to use When we compare the devices DMA mask to the amount of memory we need to make sure we treat the DMA mask as an address boundary. For example if the DMA_MASK(32) and we have 4G of memory we'd incorrectly set the dma ops to swiotlb. We need to add one to the dma mask when we convert it. Signed-off-by: Kumar Gala --- arch/powerpc/kernel/dma-swiotlb.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/dma-swiotlb.c b/arch/powerpc/kernel/dma-swiotlb.c index 59c928564a03..4ff4da2c238b 100644 --- a/arch/powerpc/kernel/dma-swiotlb.c +++ b/arch/powerpc/kernel/dma-swiotlb.c @@ -1,7 +1,8 @@ /* * Contains routines needed to support swiotlb for ppc. * - * Copyright (C) 2009 Becky Bruce, Freescale Semiconductor + * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. + * Author: Becky Bruce * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the @@ -70,7 +71,7 @@ static int ppc_swiotlb_bus_notify(struct notifier_block *nb, sd->max_direct_dma_addr = 0; /* May need to bounce if the device can't address all of DRAM */ - if (dma_get_mask(dev) < lmb_end_of_DRAM()) + if ((dma_get_mask(dev) + 1) < lmb_end_of_DRAM()) set_dma_ops(dev, &swiotlb_dma_ops); return NOTIFY_DONE;