[RFC PATCH 8/8] VFIO: do IOMMU TLB invalidation from guest

["Liu, Yi L" <yi.l.liu@xxxxxxxxx>]

From: "Liu, Yi L" <yi.l.liu@xxxxxxxxxxxxxxx>

This patch adds support for VFIO_IOMMU_TLB_INVALIDATE cmd in
vfio_iommu_type1.

For SVM virtualization on VT-d, for VFIO_IOMMU_TLB_INVALIDATE, it
calls iommu_ops->do_invalidate() to submit the guest iommu cache
invalidation to pIOMMU.

Signed-off-by: Liu, Yi L <yi.l.liu@xxxxxxxxxxxxxxx>
---
 drivers/vfio/vfio_iommu_type1.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 30b6d48..6cebdfd 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -1528,6 +1528,17 @@ static int bind_pasid_tbl_fn(struct device *dev, void *data)
 	return ret;
 }
 
+static int do_tlb_inv_fn(struct device *dev, void *data)
+{
+	int ret = 0;
+	struct vfio_svm_task *task = data;
+	struct tlb_invalidate_info *inv_info;
+
+	inv_info = task->payload;
+	ret = iommu_do_invalidate(task->domain, dev, inv_info);
+	return ret;
+}
+
 static int vfio_do_svm_task(struct vfio_iommu *iommu, void *data,
 				int (*fn)(struct device *, void *))
 {
@@ -1654,6 +1665,21 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
 		}
 		kfree(data);
 		return ret;
+	} else if (cmd == VFIO_IOMMU_TLB_INVALIDATE) {
+		struct vfio_iommu_tlb_invalidate hdr;
+		u8 *data = NULL;
+		int ret = 0;
+
+		minsz = offsetofend(struct vfio_iommu_tlb_invalidate, length);
+		if (copy_from_user(&hdr, (void __user *)arg, minsz))
+			return -EFAULT;
+		if (hdr.length == 0)
+			return -EINVAL;
+		data = memdup_user((void __user *)(arg + minsz),
+				hdr.length);
+		ret = vfio_do_svm_task(iommu, data, do_tlb_inv_fn);
+		kfree(data);
+		return ret;
 	}
 
 	return -ENOTTY;
-- 
1.9.1