[Qemu-devel] [RFC v5 3/8] memory: Add reserved_iova region type

[Eric Auger <eric.auger@redhat.com>]

Introduce a new reserved_iova region type. This type of iova region
is bound to be used by the kernel to map some host physical addresses
(typically MSI frames).

A new initializer, memory_region_init_reserved_iova is introduced, as
well as a test function, memory_region_is_reserved_iova.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 include/exec/memory.h | 29 +++++++++++++++++++++++++++++
 memory.c              | 11 +++++++++++
 2 files changed, 40 insertions(+)

diff --git a/include/exec/memory.h b/include/exec/memory.h
index 10d7eac..f97b1f4 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -191,6 +191,7 @@ struct MemoryRegion {
     /* The following fields should fit in a cache line */
     bool romd_mode;
     bool ram;
+    bool reserved_iova;
     bool subpage;
     bool readonly; /* For RAM regions */
     bool rom_device;
@@ -385,6 +386,21 @@ void memory_region_init_ram(MemoryRegion *mr,
                             Error **errp);
 
 /**
+ * memory_region_init_reserved_iova:  Initialize reserved iova memory region
+ *
+ * @mr: the #MemoryRegion to be initialized.
+ * @owner: the object that tracks the region's reference count
+ * @name: the name of the region.
+ * @size: size of the region.
+ * @errp: pointer to Error*, to store an error if it happens.
+ */
+void memory_region_init_reserved_iova(MemoryRegion *mr,
+                                      struct Object *owner,
+                                      const char *name,
+                                      uint64_t size,
+                                      Error **errp);
+
+/**
  * memory_region_init_resizeable_ram:  Initialize memory region with resizeable
  *                                     RAM.  Accesses into the region will
  *                                     modify memory directly.  Only an initial
@@ -573,6 +589,19 @@ static inline bool memory_region_is_ram(MemoryRegion *mr)
 }
 
 /**
+ * memory_region_is_reserved_iova: check whether a memory region corresponds to
+   reserved iova
+ *
+ * Returns %true is a memory region is reserved iova
+ *
+ * @mr: the memory region being queried
+ */
+static inline bool memory_region_is_reserved_iova(MemoryRegion *mr)
+{
+    return mr->reserved_iova;
+}
+
+/**
  * memory_region_is_skip_dump: check whether a memory region should not be
  *                             dumped
  *
diff --git a/memory.c b/memory.c
index 58f9269..00a0ebe 100644
--- a/memory.c
+++ b/memory.c
@@ -1309,6 +1309,17 @@ void memory_region_init_ram(MemoryRegion *mr,
     mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
 }
 
+void memory_region_init_reserved_iova(MemoryRegion *mr,
+                                      Object *owner,
+                                      const char *name,
+                                      uint64_t size,
+                                      Error **errp)
+{
+    memory_region_init(mr, owner, name, size);
+    mr->reserved_iova = true;
+    mr->terminates = true;
+}
+
 void memory_region_init_resizeable_ram(MemoryRegion *mr,
                                        Object *owner,
                                        const char *name,
-- 
1.9.1