[Qemu-devel] [PATCH 27/28] memory: check memory region endianness, not target's

[Paolo Bonzini <pbonzini@redhat.com>]

When combining multiple accesses into a single value, we need to do so
in the device's desired endianness.  The target endianness does not have
any influence.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 memory.c | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/memory.c b/memory.c
index 77a34dd..b9139c5 100644
--- a/memory.c
+++ b/memory.c
@@ -339,6 +339,15 @@ static void flatview_simplify(FlatView *view)
     }
 }
 
+static bool memory_region_big_endian(MemoryRegion *mr)
+{
+#ifdef TARGET_WORDS_BIGENDIAN
+    return mr->ops->endianness != DEVICE_LITTLE_ENDIAN;
+#else
+    return mr->ops->endianness == DEVICE_BIG_ENDIAN;
+#endif
+}
+
 static bool memory_region_wrong_endianness(MemoryRegion *mr)
 {
 #ifdef TARGET_WORDS_BIGENDIAN
@@ -454,13 +463,15 @@ static void access_with_adjusted_size(hwaddr addr,
     /* FIXME: support unaligned access? */
     access_size = MAX(MIN(size, access_size_max), access_size_min);
     access_mask = -1ULL >> (64 - access_size * 8);
-    for (i = 0; i < size; i += access_size) {
-#ifdef TARGET_WORDS_BIGENDIAN
-        access(mr, addr + i, value, access_size,
-               (size - access_size - i) * 8, access_mask);
-#else
-        access(mr, addr + i, value, access_size, i * 8, access_mask);
-#endif
+    if (memory_region_big_endian(mr)) {
+        for (i = 0; i < size; i += access_size) {
+            access(mr, addr + i, value, access_size,
+                   (size - access_size - i) * 8, access_mask);
+        }
+    } else {
+        for (i = 0; i < size; i += access_size) {
+            access(mr, addr + i, value, access_size, i * 8, access_mask);
+        }
     }
 }
 
-- 
1.8.1.4