memory: Add IOMMUTLBEvent

This way we can tell between regular IOMMUTLBEntry (entry of IOMMU
hardware) and notifications.

In the notifications, we set explicitly if it is a MAPs or an UNMAP,
instead of trusting in entry permissions to differentiate them.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20201116165506.31315-3-eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 13 insertions, 14 deletions

diff --git a/include/exec/memory.h b/include/exec/memory.h
index d8456ccf52..e86b5e92da 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -116,6 +116,11 @@ struct IOMMUNotifier {
 };
 typedef struct IOMMUNotifier IOMMUNotifier;
 
+typedef struct IOMMUTLBEvent {
+    IOMMUNotifierFlag type;
+    IOMMUTLBEntry entry;
+} IOMMUTLBEvent;
+
 /* RAM is pre-allocated and passed into qemu_ram_alloc_from_ptr */
 #define RAM_PREALLOC   (1 << 0)
 
@@ -1326,24 +1331,18 @@ uint64_t memory_region_iommu_get_min_page_size(IOMMUMemoryRegion *iommu_mr);
 /**
  * memory_region_notify_iommu: notify a change in an IOMMU translation entry.
  *
- * The notification type will be decided by entry.perm bits:
- *
- * - For UNMAP (cache invalidation) notifies: set entry.perm to IOMMU_NONE.
- * - For MAP (newly added entry) notifies: set entry.perm to the
- *   permission of the page (which is definitely !IOMMU_NONE).
- *
  * Note: for any IOMMU implementation, an in-place mapping change
  * should be notified with an UNMAP followed by a MAP.
  *
  * @iommu_mr: the memory region that was changed
  * @iommu_idx: the IOMMU index for the translation table which has changed
- * @entry: the new entry in the IOMMU translation table.  The entry
- *         replaces all old entries for the same virtual I/O address range.
- *         Deleted entries have .@perm == 0.
+ * @event: TLB event with the new entry in the IOMMU translation table.
+ *         The entry replaces all old entries for the same virtual I/O address
+ *         range.
  */
 void memory_region_notify_iommu(IOMMUMemoryRegion *iommu_mr,
                                 int iommu_idx,
-                                IOMMUTLBEntry entry);
+                                IOMMUTLBEvent event);
 
 /**
  * memory_region_notify_iommu_one: notify a change in an IOMMU translation
@@ -1353,12 +1352,12 @@ void memory_region_notify_iommu(IOMMUMemoryRegion *iommu_mr,
  * notifies a specific notifier, not all of them.
  *
  * @notifier: the notifier to be notified
- * @entry: the new entry in the IOMMU translation table.  The entry
- *         replaces all old entries for the same virtual I/O address range.
- *         Deleted entries have .@perm == 0.
+ * @event: TLB event with the new entry in the IOMMU translation table.
+ *         The entry replaces all old entries for the same virtual I/O address
+ *         range.
  */
 void memory_region_notify_iommu_one(IOMMUNotifier *notifier,
-                              IOMMUTLBEntry *entry);
+                                    IOMMUTLBEvent *event);
 
 /**
  * memory_region_register_iommu_notifier: register a notifier for changes to