[PATCH v13 10/15] vfio/type1: Implement recursive vfio_find_dma_from_node
From: Alex Williamson <hidden>
Date: 2016-10-06 20:19:57
Also in:
kvm, linux-iommu, lkml
On Thu, 6 Oct 2016 08:45:26 +0000 Eric Auger [off-list ref] wrote:
This patch handles the case where a node is encountered, matching @start and @size arguments but not matching the @type argument. In that case, we need to skip that node and pursue the search in the node's leaves. In case @start is inferior to the node's base, we resume the search on the left leaf. If the recursive search on the left leaves did not produce any match, we search the right leaves recursively. Signed-off-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Alex Williamson <redacted>
quoted hunk ↗ jump to hunk
--- v10: creation --- drivers/vfio/vfio_iommu_type1.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index cb7267a..65a4038 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c@@ -125,7 +125,17 @@ static struct vfio_dma *vfio_find_dma_from_node(struct rb_node *top, if (type == VFIO_IOVA_ANY || dma->type == type) return dma; - return NULL; + /* restart 2 searches skipping the current node */ + if (start < dma->iova) { + dma = vfio_find_dma_from_node(node->rb_left, start, + size, type); + if (dma) + return dma; + } + if (start + size > dma->iova + dma->size) + dma = vfio_find_dma_from_node(node->rb_right, start, + size, type); + return dma; } /**