[PATCH RFC v1 15/15] iommu/virtio: Update fault type and reason info for viommu fault

[Vivek Gautam]

Fault type information can tell about a page request fault or
an unreceoverable fault, and further additions to fault reasons
and the related PASID information can help in handling faults
efficiently.

Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
Cc: Eric Auger <eric.auger@xxxxxxxxxx>
Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
Cc: Liu Yi L <yi.l.liu@xxxxxxxxx>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Cc: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@xxxxxxxxxx>
---
 drivers/iommu/virtio-iommu.c      | 27 +++++++++++++++++++++++++--
 include/uapi/linux/virtio_iommu.h | 13 ++++++++++++-
 2 files changed, 37 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
index 9cc3d35125e9..10ef9e98214a 100644
--- a/drivers/iommu/virtio-iommu.c
+++ b/drivers/iommu/virtio-iommu.c
@@ -652,9 +652,16 @@ static int viommu_fault_handler(struct viommu_dev *viommu,
 	char *reason_str;
 
 	u8 reason	= fault->reason;
+	u16 type	= fault->flt_type;
 	u32 flags	= le32_to_cpu(fault->flags);
 	u32 endpoint	= le32_to_cpu(fault->endpoint);
 	u64 address	= le64_to_cpu(fault->address);
+	u32 pasid	= le32_to_cpu(fault->pasid);
+
+	if (type == VIRTIO_IOMMU_FAULT_F_PAGE_REQ) {
+		dev_info(viommu->dev, "Page request fault - unhandled\n");
+		return 0;
+	}
 
 	switch (reason) {
 	case VIRTIO_IOMMU_FAULT_R_DOMAIN:
@@ -663,6 +670,21 @@ static int viommu_fault_handler(struct viommu_dev *viommu,
 	case VIRTIO_IOMMU_FAULT_R_MAPPING:
 		reason_str = "page";
 		break;
+	case VIRTIO_IOMMU_FAULT_R_WALK_EABT:
+		reason_str = "page walk external abort";
+		break;
+	case VIRTIO_IOMMU_FAULT_R_PTE_FETCH:
+		reason_str = "pte fetch";
+		break;
+	case VIRTIO_IOMMU_FAULT_R_PERMISSION:
+		reason_str = "permission";
+		break;
+	case VIRTIO_IOMMU_FAULT_R_ACCESS:
+		reason_str = "access";
+		break;
+	case VIRTIO_IOMMU_FAULT_R_OOR_ADDRESS:
+		reason_str = "output address";
+		break;
 	case VIRTIO_IOMMU_FAULT_R_UNKNOWN:
 	default:
 		reason_str = "unknown";
@@ -671,8 +693,9 @@ static int viommu_fault_handler(struct viommu_dev *viommu,
 
 	/* TODO: find EP by ID and report_iommu_fault */
 	if (flags & VIRTIO_IOMMU_FAULT_F_ADDRESS)
-		dev_err_ratelimited(viommu->dev, "%s fault from EP %u at %#llx [%s%s%s]\n",
-				    reason_str, endpoint, address,
+		dev_err_ratelimited(viommu->dev,
+				    "%s fault from EP %u PASID %u at %#llx [%s%s%s]\n",
+				    reason_str, endpoint, pasid, address,
 				    flags & VIRTIO_IOMMU_FAULT_F_READ ? "R" : "",
 				    flags & VIRTIO_IOMMU_FAULT_F_WRITE ? "W" : "",
 				    flags & VIRTIO_IOMMU_FAULT_F_EXEC ? "X" : "");
diff --git a/include/uapi/linux/virtio_iommu.h b/include/uapi/linux/virtio_iommu.h
index 608c8d642e1f..a537d82777f7 100644
--- a/include/uapi/linux/virtio_iommu.h
+++ b/include/uapi/linux/virtio_iommu.h
@@ -290,19 +290,30 @@ struct virtio_iommu_req_invalidate {
 #define VIRTIO_IOMMU_FAULT_R_UNKNOWN		0
 #define VIRTIO_IOMMU_FAULT_R_DOMAIN		1
 #define VIRTIO_IOMMU_FAULT_R_MAPPING		2
+#define VIRTIO_IOMMU_FAULT_R_WALK_EABT		3
+#define VIRTIO_IOMMU_FAULT_R_PTE_FETCH		4
+#define VIRTIO_IOMMU_FAULT_R_PERMISSION		5
+#define VIRTIO_IOMMU_FAULT_R_ACCESS		6
+#define VIRTIO_IOMMU_FAULT_R_OOR_ADDRESS	7
 
 #define VIRTIO_IOMMU_FAULT_F_READ		(1 << 0)
 #define VIRTIO_IOMMU_FAULT_F_WRITE		(1 << 1)
 #define VIRTIO_IOMMU_FAULT_F_EXEC		(1 << 2)
 #define VIRTIO_IOMMU_FAULT_F_ADDRESS		(1 << 8)
 
+#define VIRTIO_IOMMU_FAULT_F_DMA_UNRECOV	1
+#define VIRTIO_IOMMU_FAULT_F_PAGE_REQ		2
+
 struct virtio_iommu_fault {
 	__u8					reason;
-	__u8					reserved[3];
+	__le16					flt_type;
+	__u8					reserved;
 	__le32					flags;
 	__le32					endpoint;
 	__u8					reserved2[4];
 	__le64					address;
+	__le32					pasid;
+	__u8					reserved3[4];
 };
 
 #endif
-- 
2.17.1