Re: [PATCH v10 16/16] iommu: Make iommu_report_device_fault() reutrn void

Baolu Lu
2024-01-26T06:42:32Z

On 2024/1/26 0:26, Joel Granados wrote:
> On Mon, Jan 22, 2024 at 01:43:08PM +0800, Lu Baolu wrote:
>> As the iommu_report_device_fault() has been converted to auto-respond a
>> page fault if it fails to enqueue it, there's no need to return a code
>> in any case. Make it return void.
>>
>> Suggested-by: Jason Gunthorpe<jgg@nvidia.com>
>> Signed-off-by: Lu Baolu<baolu.lu@linux.intel.com>
>> ---
>> include/linux/iommu.h | 5 ++---
>> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 4 ++--
>> drivers/iommu/intel/svm.c | 19 +++++++----------
>> drivers/iommu/io-pgfault.c | 23 +++++++--------------
>> 4 files changed, 19 insertions(+), 32 deletions(-)
>>
>> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
>> index d7b6f4017254..1ccad10e8164 100644
>> --- a/include/linux/iommu.h
>> +++ b/include/linux/iommu.h
>> @@ -1549,7 +1549,7 @@ struct iopf_queue *iopf_queue_alloc(const char *name);
>> void iopf_queue_free(struct iopf_queue *queue);
>> int iopf_queue_discard_partial(struct iopf_queue *queue);
>> void iopf_free_group(struct iopf_group *group);
>> -int iommu_report_device_fault(struct device *dev, struct iopf_fault *evt);
>> +void iommu_report_device_fault(struct device *dev, struct iopf_fault *evt);
>> void iopf_group_response(struct iopf_group *group,
>> enum iommu_page_response_code status);
>> #else
>> @@ -1587,10 +1587,9 @@ static inline void iopf_free_group(struct iopf_group *group)
>> {
>> }
>>
>> -static inline int
>> +static inline void
>> iommu_report_device_fault(struct device *dev, struct iopf_fault *evt)
>> {
>> - return -ENODEV;
>> }
>>
>> static inline void iopf_group_response(struct iopf_group *group,
>> 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 42eb59cb99f4..02580364acda 100644
>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> @@ -1455,7 +1455,7 @@ arm_smmu_find_master(struct arm_smmu_device *smmu, u32 sid)
>> /* IRQ and event handlers */
>> static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
>> {
>> - int ret;
>> + int ret = 0;
>> u32 perm = 0;
>> struct arm_smmu_master *master;
>> bool ssid_valid = evt[0] & EVTQ_0_SSV;
>> @@ -1511,7 +1511,7 @@ static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
>> goto out_unlock;
>> }
>>
>> - ret = iommu_report_device_fault(master->dev, &fault_evt);
>> + iommu_report_device_fault(master->dev, &fault_evt);
>> out_unlock:
>> mutex_unlock(&smmu->streams_mutex);
>> return ret;
>> diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
>> index 2f8716636dbb..b644d57da841 100644
>> --- a/drivers/iommu/intel/svm.c
>> +++ b/drivers/iommu/intel/svm.c
>> @@ -561,14 +561,11 @@ static int prq_to_iommu_prot(struct page_req_dsc *req)
>> return prot;
>> }
>>
>> -static int intel_svm_prq_report(struct intel_iommu *iommu, struct device *dev,
>> - struct page_req_dsc *desc)
>> +static void intel_svm_prq_report(struct intel_iommu *iommu, struct device *dev,
>> + struct page_req_dsc *desc)
>> {
>> struct iopf_fault event = { };
>>
>> - if (!dev || !dev_is_pci(dev))
>> - return -ENODEV;
>> -
>> /* Fill in event data for device specific processing */
>> event.fault.type = IOMMU_FAULT_PAGE_REQ;
>> event.fault.prm.addr = (u64)desc->addr << VTD_PAGE_SHIFT;
>> @@ -601,7 +598,7 @@ static int intel_svm_prq_report(struct intel_iommu *iommu, struct device *dev,
>> event.fault.prm.private_data[0] = ktime_to_ns(ktime_get());
>> }
>>
>> - return iommu_report_device_fault(dev, &event);
>> + iommu_report_device_fault(dev, &event);
>> }
>>
>> static void handle_bad_prq_event(struct intel_iommu *iommu,
>> @@ -704,12 +701,10 @@ static irqreturn_t prq_event_thread(int irq, void *d)
>> if (!pdev)
>> goto bad_req;
>>
>> - if (intel_svm_prq_report(iommu, &pdev->dev, req))
>> - handle_bad_prq_event(iommu, req, QI_RESP_INVALID);
>> - else
>> - trace_prq_report(iommu, &pdev->dev, req->qw_0, req->qw_1,
>> - req->priv_data[0], req->priv_data[1],
>> - iommu->prq_seq_number++);
>> + intel_svm_prq_report(iommu, &pdev->dev, req);
>> + trace_prq_report(iommu, &pdev->dev, req->qw_0, req->qw_1,
>> + req->priv_data[0], req->priv_data[1],
>> + iommu->prq_seq_number++);
>> pci_dev_put(pdev);
>> prq_advance:
>> head = (head + sizeof(*req)) & PRQ_RING_MASK;
>> diff --git a/drivers/iommu/io-pgfault.c b/drivers/iommu/io-pgfault.c
>> index 6e63e5a02884..b64229dab976 100644
>> --- a/drivers/iommu/io-pgfault.c
>> +++ b/drivers/iommu/io-pgfault.c
>> @@ -179,23 +179,21 @@ static struct iopf_group *iopf_group_alloc(struct iommu_fault_param *iopf_param,
>> *
>> * Return: 0 on success and <0 on error.
>> */
> Should you remove the documentation that describes the return also?

Yes. Will do.

Best regards,
baolu