Attachment 312135 Details for Bug 455813 – Additional Upstream bug fix related to this issue

[patch] Additional Upstream bug fix related to this issue

upstream2.patch (text/plain), 1.92 KB, created by Prarit Bhargava on 2008-07-18 13:41:20 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Prarit Bhargava

Created: 2008-07-18 13:41:20 UTC

Size: 1.92 KB

patch

obsolete

>pci_alloc_consistent/dma_alloc_coherent is supposed to return size aligned
>addresses.
>
>From Documentation/DMA-mapping.txt:
>
>"pci_alloc_consistent returns two values: the virtual address which you
>can use to access it from the CPU and dma_handle which you pass to the
>card.
>
>The cpu return address and the DMA bus master address are both
>guaranteed to be aligned to the smallest PAGE_SIZE order which
>is greater than or equal to the requested size.  This invariant
>exists (for example) to guarantee that if you allocate a chunk
>which is smaller than or equal to 64 kilobytes, the extent of the
>buffer you receive will not cross a 64K boundary."
>
>Fix the GART's alloc_iommu code to return a size aligned address.  Also fix
>an incorrect alignment calculation in the iommu-helper code.
>
>Signed-off-by: Prarit Bhargava <prarit@redhat.com>
>
>diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c
>index faf3229..329718e 100644
>--- a/arch/x86/kernel/pci-gart_64.c
>+++ b/arch/x86/kernel/pci-gart_64.c
>@@ -96,11 +96,12 @@ static unsigned long alloc_iommu(struct device *dev, int size)
> 
> 	spin_lock_irqsave(&iommu_bitmap_lock, flags);
> 	offset = iommu_area_alloc(iommu_gart_bitmap, iommu_pages, next_bit,
>-				  size, base_index, boundary_size, 0);
>+				  size, base_index, boundary_size, size - 1);
> 	if (offset == -1) {
> 		need_flush = 1;
> 		offset = iommu_area_alloc(iommu_gart_bitmap, iommu_pages, 0,
>-					  size, base_index, boundary_size, 0);
>+					  size, base_index, boundary_size,
>+					  size - 1);
> 	}
> 	if (offset != -1) {
> 		set_bit_string(iommu_gart_bitmap, offset, size);
>diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c
>index a3b8d4c..b970f1b 100644
>--- a/lib/iommu-helper.c
>+++ b/lib/iommu-helper.c
>@@ -16,7 +16,7 @@ again:
> 	index = find_next_zero_bit(map, size, start);
> 
> 	/* Align allocation */
>-	index = (index + align_mask) & ~align_mask;
>+	index = (index + align_mask + 1) & ~align_mask;
> 
> 	end = index + nr;
> 	if (end >= size)

Actions: View | Diff

Attachments on bug 455813: 312088 | 312089 | 312135 | 312136 | 312164 | 312463 | 313699