From 449fa54d6815be8c2c1f68fa9dbbae9384a7c03e Mon Sep 17 00:00:00 2001 From: Fugang Duan Date: Fri, 19 Jul 2019 17:26:48 +0800 Subject: [PATCH] dma-direct: correct the physical addr in dma_direct_sync_sg_for_cpu/device dma_map_sg() may use swiotlb buffer when the kernel command line includes "swiotlb=force" or the dma_addr is out of dev->dma_mask range. After DMA complete the memory moving from device to memory, then user call dma_sync_sg_for_cpu() to sync with DMA buffer, and copy the original virtual buffer to other space. So dma_direct_sync_sg_for_cpu() should use swiotlb physical addr, not the original physical addr from sg_phys(sg). dma_direct_sync_sg_for_device() also has the same issue, correct it as well. Fixes: 55897af63091("dma-direct: merge swiotlb_dma_ops into the dma_direct code") Signed-off-by: Fugang Duan Reviewed-by: Robin Murphy Signed-off-by: Christoph Hellwig --- kernel/dma/direct.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index e269b6f9b444..59bdceea3737 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -234,12 +234,14 @@ void dma_direct_sync_sg_for_device(struct device *dev, int i; for_each_sg(sgl, sg, nents, i) { - if (unlikely(is_swiotlb_buffer(sg_phys(sg)))) - swiotlb_tbl_sync_single(dev, sg_phys(sg), sg->length, + phys_addr_t paddr = dma_to_phys(dev, sg_dma_address(sg)); + + if (unlikely(is_swiotlb_buffer(paddr))) + swiotlb_tbl_sync_single(dev, paddr, sg->length, dir, SYNC_FOR_DEVICE); if (!dev_is_dma_coherent(dev)) - arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, + arch_sync_dma_for_device(dev, paddr, sg->length, dir); } } @@ -271,11 +273,13 @@ void dma_direct_sync_sg_for_cpu(struct device *dev, int i; for_each_sg(sgl, sg, nents, i) { + phys_addr_t paddr = dma_to_phys(dev, sg_dma_address(sg)); + if (!dev_is_dma_coherent(dev)) - arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir); - - if (unlikely(is_swiotlb_buffer(sg_phys(sg)))) - swiotlb_tbl_sync_single(dev, sg_phys(sg), sg->length, dir, + arch_sync_dma_for_cpu(dev, paddr, sg->length, dir); + + if (unlikely(is_swiotlb_buffer(paddr))) + swiotlb_tbl_sync_single(dev, paddr, sg->length, dir, SYNC_FOR_CPU); } -- 2.21.0