[PATCH v3 02/11] iommu/arm-smmu-v3: Remove unrecoverable faults reporting

From: Lu Baolu
Date: Thu Aug 17 2023 - 19:44:28 EST


No device driver registers fault handler to handle the reported
unrecoveraable faults. Remove it to avoid dead code.

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 46 ++++++---------------
1 file changed, 13 insertions(+), 33 deletions(-)

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 ee70687f060b..e08d2e27a9e5 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -1469,7 +1469,6 @@ arm_smmu_find_master(struct arm_smmu_device *smmu, u32 sid)
static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
{
int ret;
- u32 reason;
u32 perm = 0;
struct arm_smmu_master *master;
bool ssid_valid = evt[0] & EVTQ_0_SSV;
@@ -1479,16 +1478,9 @@ static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)

switch (FIELD_GET(EVTQ_0_ID, evt[0])) {
case EVT_ID_TRANSLATION_FAULT:
- reason = IOMMU_FAULT_REASON_PTE_FETCH;
- break;
case EVT_ID_ADDR_SIZE_FAULT:
- reason = IOMMU_FAULT_REASON_OOR_ADDRESS;
- break;
case EVT_ID_ACCESS_FAULT:
- reason = IOMMU_FAULT_REASON_ACCESS;
- break;
case EVT_ID_PERMISSION_FAULT:
- reason = IOMMU_FAULT_REASON_PERMISSION;
break;
default:
return -EOPNOTSUPP;
@@ -1498,6 +1490,9 @@ static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
if (evt[1] & EVTQ_1_S2)
return -EFAULT;

+ if (!(evt[1] & EVTQ_1_STALL))
+ return -EOPNOTSUPP;
+
if (evt[1] & EVTQ_1_RnW)
perm |= IOMMU_FAULT_PERM_READ;
else
@@ -1509,32 +1504,17 @@ static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
if (evt[1] & EVTQ_1_PnU)
perm |= IOMMU_FAULT_PERM_PRIV;

- if (evt[1] & EVTQ_1_STALL) {
- flt->type = IOMMU_FAULT_PAGE_REQ;
- flt->prm = (struct iommu_fault_page_request) {
- .flags = IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE,
- .grpid = FIELD_GET(EVTQ_1_STAG, evt[1]),
- .perm = perm,
- .addr = FIELD_GET(EVTQ_2_ADDR, evt[2]),
- };
+ flt->type = IOMMU_FAULT_PAGE_REQ;
+ flt->prm = (struct iommu_fault_page_request) {
+ .flags = IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE,
+ .grpid = FIELD_GET(EVTQ_1_STAG, evt[1]),
+ .perm = perm,
+ .addr = FIELD_GET(EVTQ_2_ADDR, evt[2]),
+ };

- if (ssid_valid) {
- flt->prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
- flt->prm.pasid = FIELD_GET(EVTQ_0_SSID, evt[0]);
- }
- } else {
- flt->type = IOMMU_FAULT_DMA_UNRECOV;
- flt->event = (struct iommu_fault_unrecoverable) {
- .reason = reason,
- .flags = IOMMU_FAULT_UNRECOV_ADDR_VALID,
- .perm = perm,
- .addr = FIELD_GET(EVTQ_2_ADDR, evt[2]),
- };
-
- if (ssid_valid) {
- flt->event.flags |= IOMMU_FAULT_UNRECOV_PASID_VALID;
- flt->event.pasid = FIELD_GET(EVTQ_0_SSID, evt[0]);
- }
+ if (ssid_valid) {
+ flt->prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
+ flt->prm.pasid = FIELD_GET(EVTQ_0_SSID, evt[0]);
}

mutex_lock(&smmu->streams_mutex);
--
2.34.1