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[v3,14/14] iommu/arm-smmu-v3: Report IRQs that belong to devices attached to vIOMMU

Message ID 18cf51aa592840e9cd92a9ea1a157607db1a681a.1734477608.git.nicolinc@nvidia.com (mailing list archive)
State New
Headers show
Series iommufd: Add vIOMMU infrastructure (Part-3: vIRQ) | expand

Commit Message

Nicolin Chen Dec. 18, 2024, 5 a.m. UTC
Aside from the IOPF framework, iommufd provides an additional pathway to
report a hardware event or IRQ, via the vIRQ of vIOMMU infrastructure.

Define an iommu_virq_arm_smmuv3 uAPI structure, and report stage-1 faults
in the threaded IRQ handler.

Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h   |  7 +++
 include/uapi/linux/iommufd.h                  | 15 +++++
 .../arm/arm-smmu-v3/arm-smmu-v3-iommufd.c     | 16 +++++
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c   | 58 +++++++++++--------
 4 files changed, 71 insertions(+), 25 deletions(-)
diff mbox series

Patch

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index 4435ad7db776..d24c3d8ee397 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -1066,6 +1066,7 @@  struct iommufd_viommu *arm_vsmmu_alloc(struct device *dev,
 int arm_smmu_attach_prepare_vmaster(struct arm_smmu_attach_state *state,
 				    struct iommu_domain *domain);
 void arm_smmu_attach_commit_vmaster(struct arm_smmu_attach_state *state);
+int arm_vmaster_report_event(struct arm_smmu_vmaster *vmaster, u64 *evt);
 #else
 #define arm_smmu_hw_info NULL
 #define arm_vsmmu_alloc NULL
@@ -1081,6 +1082,12 @@  static inline void
 arm_smmu_attach_commit_vmaster(struct arm_smmu_attach_state *state)
 {
 }
+
+static inline int arm_vmaster_report_event(struct arm_smmu_vmaster *vmaster,
+					   u64 *evt)
+{
+	return -EOPNOTSUPP;
+}
 #endif /* CONFIG_ARM_SMMU_V3_IOMMUFD */
 
 #endif /* _ARM_SMMU_V3_H */
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index cdf2dba28d4a..579529ff6fa7 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -1016,9 +1016,24 @@  struct iommu_ioas_change_process {
 /**
  * enum iommu_virq_type - Virtual IRQ Type
  * @IOMMU_VIRQ_TYPE_NONE: INVALID type
+ * @IOMMU_VIRQ_TYPE_ARM_SMMUV3: ARM SMMUv3 Virtual Event
  */
 enum iommu_virq_type {
 	IOMMU_VIRQ_TYPE_NONE = 0,
+	IOMMU_VIRQ_TYPE_ARM_SMMUV3 = 1,
+};
+
+/**
+ * struct iommu_virq_arm_smmuv3 - ARM SMMUv3 Virtual IRQ
+ *                                (IOMMU_VIRQ_TYPE_ARM_SMMUV3)
+ * @evt: 256-bit ARM SMMUv3 Event record, little-endian.
+ *       (Refer to "7.3 Event records" in SMMUv3 HW Spec)
+ *
+ * StreamID field reports a virtual device ID. To receive a virtual IRQ for a
+ * device, a vDEVICE must be allocated via IOMMU_VDEVICE_ALLOC.
+ */
+struct iommu_virq_arm_smmuv3 {
+	__aligned_le64 evt[4];
 };
 
 /**
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
index 2b6253ef0e8f..e85456c7ff52 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
@@ -447,4 +447,20 @@  struct iommufd_viommu *arm_vsmmu_alloc(struct device *dev,
 	return &vsmmu->core;
 }
 
+int arm_vmaster_report_event(struct arm_smmu_vmaster *vmaster, u64 *evt)
+{
+	struct iommu_virq_arm_smmuv3 virq_data =
+		*(struct iommu_virq_arm_smmuv3 *)evt;
+
+	virq_data.evt[0] &= ~EVTQ_0_SID;
+	virq_data.evt[0] |= FIELD_PREP(EVTQ_0_SID, vmaster->vsid);
+
+	virq_data.evt[0] = cpu_to_le64(virq_data.evt[0]);
+	virq_data.evt[1] = cpu_to_le64(virq_data.evt[1]);
+
+	return iommufd_viommu_report_irq(&vmaster->vsmmu->core,
+					 IOMMU_VIRQ_TYPE_ARM_SMMUV3, &virq_data,
+					 sizeof(virq_data));
+}
+
 MODULE_IMPORT_NS("IOMMUFD");
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 686c171dd273..59fbc342a095 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -1812,8 +1812,8 @@  static void arm_smmu_decode_event(struct arm_smmu_device *smmu, u64 *raw,
 	mutex_unlock(&smmu->streams_mutex);
 }
 
-static int arm_smmu_handle_event(struct arm_smmu_device *smmu,
-			       struct arm_smmu_event *event)
+static int arm_smmu_handle_event(struct arm_smmu_device *smmu, u64 *evt,
+				 struct arm_smmu_event *event)
 {
 	int ret = 0;
 	u32 perm = 0;
@@ -1831,31 +1831,30 @@  static int arm_smmu_handle_event(struct arm_smmu_device *smmu,
 		return -EOPNOTSUPP;
 	}
 
-	if (!event->stall)
-		return -EOPNOTSUPP;
-
-	if (event->read)
-		perm |= IOMMU_FAULT_PERM_READ;
-	else
-		perm |= IOMMU_FAULT_PERM_WRITE;
+	if (event->stall) {
+		if (event->read)
+			perm |= IOMMU_FAULT_PERM_READ;
+		else
+			perm |= IOMMU_FAULT_PERM_WRITE;
 
-	if (event->instruction)
-		perm |= IOMMU_FAULT_PERM_EXEC;
+		if (event->instruction)
+			perm |= IOMMU_FAULT_PERM_EXEC;
 
-	if (event->privileged)
-		perm |= IOMMU_FAULT_PERM_PRIV;
+		if (event->privileged)
+			perm |= IOMMU_FAULT_PERM_PRIV;
 
-	flt->type = IOMMU_FAULT_PAGE_REQ;
-	flt->prm = (struct iommu_fault_page_request) {
-		.flags = IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE,
-		.grpid = event->stag,
-		.perm = perm,
-		.addr = event->iova,
-	};
+		flt->type = IOMMU_FAULT_PAGE_REQ;
+		flt->prm = (struct iommu_fault_page_request){
+			.flags = IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE,
+			.grpid = event->stag,
+			.perm = perm,
+			.addr = event->iova,
+		};
 
-	if (event->ssv) {
-		flt->prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
-		flt->prm.pasid = event->ssid;
+		if (event->ssv) {
+			flt->prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
+			flt->prm.pasid = event->ssid;
+		}
 	}
 
 	mutex_lock(&smmu->streams_mutex);
@@ -1865,7 +1864,16 @@  static int arm_smmu_handle_event(struct arm_smmu_device *smmu,
 		goto out_unlock;
 	}
 
-	ret = iommu_report_device_fault(master->dev, &fault_evt);
+	if (event->stall) {
+		ret = iommu_report_device_fault(master->dev, &fault_evt);
+	} else {
+		down_read(&master->vmaster_rwsem);
+		if (master->vmaster && !event->s2)
+			ret = arm_vmaster_report_event(master->vmaster, evt);
+		else
+			ret = -EFAULT; /* Unhandled events should be pinned */
+		up_read(&master->vmaster_rwsem);
+	}
 out_unlock:
 	mutex_unlock(&smmu->streams_mutex);
 	return ret;
@@ -1943,7 +1951,7 @@  static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
 	do {
 		while (!queue_remove_raw(q, evt)) {
 			arm_smmu_decode_event(smmu, evt, &event);
-			if (arm_smmu_handle_event(smmu, &event))
+			if (arm_smmu_handle_event(smmu, evt, &event))
 				arm_smmu_dump_event(smmu, evt, &event, &rs);
 
 			put_device(event.dev);