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-rw-r--r--include/exec/memattrs.h45
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diff --git a/include/exec/memattrs.h b/include/exec/memattrs.h
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+/*
+ * Memory transaction attributes
+ *
+ * Copyright (c) 2015 Linaro Limited.
+ *
+ * Authors:
+ *  Peter Maydell <peter.maydell@linaro.org>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef MEMATTRS_H
+#define MEMATTRS_H
+
+/* Every memory transaction has associated with it a set of
+ * attributes. Some of these are generic (such as the ID of
+ * the bus master); some are specific to a particular kind of
+ * bus (such as the ARM Secure/NonSecure bit). We define them
+ * all as non-overlapping bitfields in a single struct to avoid
+ * confusion if different parts of QEMU used the same bit for
+ * different semantics.
+ */
+typedef struct MemTxAttrs {
+    /* Bus masters which don't specify any attributes will get this
+     * (via the MEMTXATTRS_UNSPECIFIED constant), so that we can
+     * distinguish "all attributes deliberately clear" from
+     * "didn't specify" if necessary.
+     */
+    unsigned int unspecified:1;
+    /* ARM/AMBA TrustZone Secure access */
+    unsigned int secure:1;
+    /* Memory access is usermode (unprivileged) */
+    unsigned int user:1;
+} MemTxAttrs;
+
+/* Bus masters which don't specify any attributes will get this,
+ * which has all attribute bits clear except the topmost one
+ * (so that we can distinguish "all attributes deliberately clear"
+ * from "didn't specify" if necessary).
+ */
+#define MEMTXATTRS_UNSPECIFIED ((MemTxAttrs) { .unspecified = 1 })
+
+#endif