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 <nicol...@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 --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);
--
2.43.0
