[PATCH 07/37] iommu: Add a page fault handler

On 05/03/18 21:44, Sinan Kaya wrote:

On 2/12/2018 1:33 PM, Jean-Philippe Brucker wrote:

quoted

+static int iommu_queue_fault(struct iommu_domain *domain, struct device *dev,
+			     struct iommu_fault_event *evt)
+{
+	struct iommu_fault_group *group;
+	struct iommu_fault_context *fault, *next;
+
+	if (!iommu_fault_queue)
+		return -ENOSYS;
+
+	if (!evt->last_req) {
+		fault = kzalloc(sizeof(*fault), GFP_KERNEL);
+		if (!fault)
+			return -ENOMEM;
+
+		fault->evt = *evt;
+		fault->dev = dev;
+
+		/* Non-last request of a group. Postpone until the last one */
+		spin_lock(&iommu_partial_faults_lock);
+		list_add_tail(&fault->head, &iommu_partial_faults);
+		spin_unlock(&iommu_partial_faults_lock);
+
+		return IOMMU_PAGE_RESP_HANDLED;
+	}
+
+	group = kzalloc(sizeof(*group), GFP_KERNEL);
+	if (!group)
+		return -ENOMEM;

Release the requests in iommu_partial_faults here.

We move these requests to the group->faults list (which btw should use
list_move instead of the current list_del+list_add) and we release them in
iommu_fault_handle_group()

Thanks,
Jean