Commit 40ae9b80 authored by Steve Sistare's avatar Steve Sistare Committed by Alex Williamson
Browse files

vfio/type1: massage unmap iteration 



Modify the iteration in vfio_dma_do_unmap so it does not depend on deletion
of each dma entry.  Add a variant of vfio_find_dma that returns the entry
with the lowest iova in the search range to initialize the iteration.  No
externally visible change, but this behavior is needed in the subsequent
update-vaddr patch.

Signed-off-by: default avatarSteve Sistare <steven.sistare@oracle.com>
Reviewed-by: default avatarCornelia Huck <cohuck@redhat.com>
Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent 441e8106

drivers/vfio/vfio_iommu_type1.c

+34 −1
Original line number Diff line number Diff line
@@ -173,6 +173,31 @@ static struct vfio_dma *vfio_find_dma(struct vfio_iommu *iommu, 
	return NULL;

}



static struct rb_node *vfio_find_dma_first_node(struct vfio_iommu *iommu,

						dma_addr_t start, size_t size)

{

	struct rb_node *res = NULL;

	struct rb_node *node = iommu->dma_list.rb_node;

	struct vfio_dma *dma_res = NULL;



	while (node) {

		struct vfio_dma *dma = rb_entry(node, struct vfio_dma, node);



		if (start < dma->iova + dma->size) {

			res = node;

			dma_res = dma;

			if (start >= dma->iova)

				break;

			node = node->rb_left;

		} else {

			node = node->rb_right;

		}

	}

	if (res && size && dma_res->iova >= start + size)

		res = NULL;

	return res;

}



static void vfio_link_dma(struct vfio_iommu *iommu, struct vfio_dma *new)

{

	struct rb_node **link = &iommu->dma_list.rb_node, *parent = NULL;
@@ -1079,6 +1104,7 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu, 
	dma_addr_t iova = unmap->iova;

	unsigned long size = unmap->size;

	bool unmap_all = unmap->flags & VFIO_DMA_UNMAP_FLAG_ALL;

	struct rb_node *n;



	mutex_lock(&iommu->lock);
@@ -1149,7 +1175,13 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu, 
	}



	ret = 0;

	while ((dma = vfio_find_dma(iommu, iova, size))) {

	n = vfio_find_dma_first_node(iommu, iova, size);



	while (n) {

		dma = rb_entry(n, struct vfio_dma, node);

		if (dma->iova >= iova + size)

			break;



		if (!iommu->v2 && iova > dma->iova)

			break;

		/*
@@ -1194,6 +1226,7 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu, 
		}



		unmapped += dma->size;

		n = rb_next(n);

		vfio_remove_dma(iommu, dma);

	}