vfio iommu type1: Fix size argument to vfio_find_dma() in pin_pages/unpin_pages

Passing zero for the size to vfio_find_dma() isn't compatible with
matching the start address of an existing vfio_dma. Doing so triggers a
corner case. In vfio_find_dma(), when the start address is equal to
dma->iova and size is 0, check for the end of search range makes it to
take wrong side of RB-tree. That fails the search even though the address
is present in mapped dma ranges.
In functions pin_pages and unpin_pages, the iova which is being searched
is base address of page to be pinned or unpinned. So here size should be
set to PAGE_SIZE, as argument to vfio_find_dma().

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Kirti Wankhede 2016-12-06 23:58:12 +05:30 committed by Alex Williamson
parent 7c03f42846
commit 2b8bb1d771

View File

@ -581,7 +581,7 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data,
struct vfio_pfn *vpfn;
iova = user_pfn[i] << PAGE_SHIFT;
dma = vfio_find_dma(iommu, iova, 0);
dma = vfio_find_dma(iommu, iova, PAGE_SIZE);
if (!dma) {
ret = -EINVAL;
goto pin_unwind;
@ -622,7 +622,7 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data,
dma_addr_t iova;
iova = user_pfn[j] << PAGE_SHIFT;
dma = vfio_find_dma(iommu, iova, 0);
dma = vfio_find_dma(iommu, iova, PAGE_SIZE);
vfio_unpin_page_external(dma, iova, do_accounting);
phys_pfn[j] = 0;
}
@ -659,7 +659,7 @@ static int vfio_iommu_type1_unpin_pages(void *iommu_data,
dma_addr_t iova;
iova = user_pfn[i] << PAGE_SHIFT;
dma = vfio_find_dma(iommu, iova, 0);
dma = vfio_find_dma(iommu, iova, PAGE_SIZE);
if (!dma)
goto unpin_exit;
vfio_unpin_page_external(dma, iova, do_accounting);