Messages in this thread Patch in this message | | | From | Mark Craske <> | Subject | [PATCH v1 1/2] drivers: dma-coherent: Fix DMA coherent size for less than page | Date | Thu, 15 Sep 2016 10:39:58 +0100 |
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From: "George G. Davis" <george_davis@mentor.com>
We fix a bug in dma_mmap_from_coherent() that appears when we map non page aligned DMA memory. It cuts off the non aligned part (this is different to dma_alloc_coherent() that always rounds up to full pages). So for mappings of less than a page we get -ENXIO as dma_mmap_from_coherent() assumes we want to map zero pages.
Signed-off-by: George G. Davis <george_davis@mentor.com> Signed-off-by: Jiada Wang <jiada_wang@mentor.com> Signed-off-by: Mark Craske <Mark_Craske@mentor.com> --- drivers/base/dma-coherent.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c index bdf28f7..abd83b7 100644 --- a/drivers/base/dma-coherent.c +++ b/drivers/base/dma-coherent.c @@ -262,7 +262,7 @@ int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma, unsigned long off = vma->vm_pgoff; int start = (vaddr - mem->virt_base) >> PAGE_SHIFT; int user_count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; - int count = size >> PAGE_SHIFT; + int count = PAGE_ALIGN(size) >> PAGE_SHIFT; *ret = -ENXIO; if (off < count && user_count <= count - off) { -- 1.7.9.5
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