iommu/amd: Add invalid_ppr callback
Joerg Roedel [Mon, 28 Nov 2011 13:36:36 +0000 (14:36 +0100)]
This callback can be used to change the PRI response code
sent to a device when a PPR fault fails.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

drivers/iommu/amd_iommu_v2.c
include/linux/amd-iommu.h

index abdb839..fe812e2 100644 (file)
@@ -62,6 +62,7 @@ struct device_state {
        struct iommu_domain *domain;
        int pasid_levels;
        int max_pasids;
+       amd_iommu_invalid_ppr_cb inv_ppr_cb;
        spinlock_t lock;
        wait_queue_head_t wq;
 };
@@ -505,10 +506,31 @@ static void do_fault(struct work_struct *work)
        npages = get_user_pages(fault->state->task, fault->state->mm,
                                fault->address, 1, write, 0, &page, NULL);
 
-       if (npages == 1)
+       if (npages == 1) {
                put_page(page);
-       else
+       } else if (fault->dev_state->inv_ppr_cb) {
+               int status;
+
+               status = fault->dev_state->inv_ppr_cb(fault->dev_state->pdev,
+                                                     fault->pasid,
+                                                     fault->address,
+                                                     fault->flags);
+               switch (status) {
+               case AMD_IOMMU_INV_PRI_RSP_SUCCESS:
+                       set_pri_tag_status(fault->state, fault->tag, PPR_SUCCESS);
+                       break;
+               case AMD_IOMMU_INV_PRI_RSP_INVALID:
+                       set_pri_tag_status(fault->state, fault->tag, PPR_INVALID);
+                       break;
+               case AMD_IOMMU_INV_PRI_RSP_FAIL:
+                       set_pri_tag_status(fault->state, fault->tag, PPR_FAILURE);
+                       break;
+               default:
+                       BUG();
+               }
+       } else {
                set_pri_tag_status(fault->state, fault->tag, PPR_INVALID);
+       }
 
        finish_pri_tag(fault->dev_state, fault->state, fault->tag);
 
@@ -828,6 +850,37 @@ void amd_iommu_free_device(struct pci_dev *pdev)
 }
 EXPORT_SYMBOL(amd_iommu_free_device);
 
+int amd_iommu_set_invalid_ppr_cb(struct pci_dev *pdev,
+                                amd_iommu_invalid_ppr_cb cb)
+{
+       struct device_state *dev_state;
+       unsigned long flags;
+       u16 devid;
+       int ret;
+
+       if (!amd_iommu_v2_supported())
+               return -ENODEV;
+
+       devid = device_id(pdev);
+
+       spin_lock_irqsave(&state_lock, flags);
+
+       ret = -EINVAL;
+       dev_state = state_table[devid];
+       if (dev_state == NULL)
+               goto out_unlock;
+
+       dev_state->inv_ppr_cb = cb;
+
+       ret = 0;
+
+out_unlock:
+       spin_unlock_irqrestore(&state_lock, flags);
+
+       return ret;
+}
+EXPORT_SYMBOL(amd_iommu_set_invalid_ppr_cb);
+
 static int __init amd_iommu_v2_init(void)
 {
        size_t state_table_size;
index 23e21e1..06688c4 100644 (file)
@@ -28,9 +28,6 @@ struct task_struct;
 struct pci_dev;
 
 extern int amd_iommu_detect(void);
-extern int amd_iommu_bind_pasid(struct pci_dev *pdev, int pasid,
-                               struct task_struct *task);
-extern void amd_iommu_unbind_pasid(struct pci_dev *pdev, int pasid);
 
 
 /**
@@ -91,6 +88,37 @@ extern int amd_iommu_bind_pasid(struct pci_dev *pdev, int pasid,
  */
 extern void amd_iommu_unbind_pasid(struct pci_dev *pdev, int pasid);
 
+/**
+ * amd_iommu_set_invalid_ppr_cb() - Register a call-back for failed
+ *                                 PRI requests
+ * @pdev: The PCI device the call-back should be registered for
+ * @cb: The call-back function
+ *
+ * The IOMMUv2 driver invokes this call-back when it is unable to
+ * successfully handle a PRI request. The device driver can then decide
+ * which PRI response the device should see. Possible return values for
+ * the call-back are:
+ *
+ * - AMD_IOMMU_INV_PRI_RSP_SUCCESS - Send SUCCESS back to the device
+ * - AMD_IOMMU_INV_PRI_RSP_INVALID - Send INVALID back to the device
+ * - AMD_IOMMU_INV_PRI_RSP_FAIL    - Send Failure back to the device,
+ *                                  the device is required to disable
+ *                                  PRI when it receives this response
+ *
+ * The function returns 0 on success or negative value on error.
+ */
+#define AMD_IOMMU_INV_PRI_RSP_SUCCESS  0
+#define AMD_IOMMU_INV_PRI_RSP_INVALID  1
+#define AMD_IOMMU_INV_PRI_RSP_FAIL     2
+
+typedef int (*amd_iommu_invalid_ppr_cb)(struct pci_dev *pdev,
+                                       int pasid,
+                                       unsigned long address,
+                                       u16);
+
+extern int amd_iommu_set_invalid_ppr_cb(struct pci_dev *pdev,
+                                       amd_iommu_invalid_ppr_cb cb);
+
 #else
 
 static inline int amd_iommu_detect(void) { return -ENODEV; }