On 12/12/23 11:18 PM, Jason Gunthorpe wrote:
On Tue, Dec 12, 2023 at 01:07:17PM +0800, Baolu Lu wrote:Yes, agreed. The iopf_fault_param should be passed in together with the iopf_group. The reference count should be released in the iopf_free_group(). These two helps could look like below: int iommu_page_response(struct iopf_group *group, struct iommu_page_response *msg) { bool needs_pasid; int ret = -EINVAL; struct iopf_fault *evt; struct iommu_fault_page_request *prm; struct device *dev = group->fault_param->dev; const struct iommu_ops *ops = dev_iommu_ops(dev); bool has_pasid = msg->flags & IOMMU_PAGE_RESP_PASID_VALID; struct iommu_fault_param *fault_param = group->fault_param; if (!ops->page_response) return -ENODEV;We should never get here if this is the case, prevent the device from being added in the first place
Yeah, could move it to iopf_queue_add_device(). WARN and return failure there if the driver is not ready for page request handling.
/* Only send response if there is a fault report pending */ mutex_lock(&fault_param->lock); if (list_empty(&fault_param->faults)) { dev_warn_ratelimited(dev, "no pending PRQ, drop response\n"); goto done_unlock; } /* * Check if we have a matching page request pending to respond, * otherwise return -EINVAL */ list_for_each_entry(evt, &fault_param->faults, list) { prm = &evt->fault.prm; if (prm->grpid != msg->grpid) continue; /* * If the PASID is required, the corresponding request is * matched using the group ID, the PASID valid bit and the PASID * value. Otherwise only the group ID matches request and * response. */ needs_pasid = prm->flags & IOMMU_FAULT_PAGE_RESPONSE_NEEDS_PASID; if (needs_pasid && (!has_pasid || msg->pasid != prm->pasid)) continue; if (!needs_pasid && has_pasid) { /* No big deal, just clear it. */ msg->flags &= ~IOMMU_PAGE_RESP_PASID_VALID; msg->pasid = 0; } ret = ops->page_response(dev, evt, msg); list_del(&evt->list); kfree(evt); break; } done_unlock: mutex_unlock(&fault_param->lock);I would have expected the group to free'd here? But regardless this looks like a good direction
Both work for me. We can decide it according to the needs of code later.
Jason
Best regards, baolu
