exec: always call qemu_get_ram_ptr within rcu_read_lock

[mirror_qemu.git] / include / exec / memory.h

diff --git a/include/exec/memory.h b/include/exec/memory.h
index 5baaf48234b9116ef5d2f3833b0ab07ff35e1ce9..9bbd247c38cd5cce7b4f68446ea778de4522311b 100644 (file)
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -582,6 +582,19 @@ void memory_region_notify_iommu(MemoryRegion *mr,
  */
 void memory_region_register_iommu_notifier(MemoryRegion *mr, Notifier *n);
 
+/**
+ * memory_region_iommu_replay: replay existing IOMMU translations to
+ * a notifier
+ *
+ * @mr: the memory region to observe
+ * @n: the notifier to which to replay iommu mappings
+ * @granularity: Minimum page granularity to replay notifications for
+ * @is_write: Whether to treat the replay as a translate "write"
+ *     through the iommu
+ */
+void memory_region_iommu_replay(MemoryRegion *mr, Notifier *n,
+                                hwaddr granularity, bool is_write);
+
 /**
  * memory_region_unregister_iommu_notifier: unregister a notifier for
  * changes to IOMMU translation entries.
@@ -643,8 +656,13 @@ int memory_region_get_fd(MemoryRegion *mr);
  * memory_region_get_ram_ptr: Get a pointer into a RAM memory region.
  *
  * Returns a host pointer to a RAM memory region (created with
- * memory_region_init_ram() or memory_region_init_ram_ptr()).  Use with
- * care.
+ * memory_region_init_ram() or memory_region_init_ram_ptr()).
+ *
+ * Use with care; by the time this function returns, the returned pointer is
+ * not protected by RCU anymore.  If the caller is not within an RCU critical
+ * section and does not hold the iothread lock, it must have other means of
+ * protecting the pointer, such as a reference to the region that includes
+ * the incoming ram_addr_t.
  *
  * @mr: the memory region being queried.
  */