1 files changed, 85 insertions, 0 deletions
diff --git a/scripts/qemugdb/mtree.py b/scripts/qemugdb/mtree.py
new file mode 100644
index 000000000..8fe42c3c1
--- /dev/null
+++ b/scripts/qemugdb/mtree.py
@@ -0,0 +1,85 @@
+#
+# GDB debugging support
+#
+# Copyright 2012 Red Hat, Inc. and/or its affiliates
+#
+# Authors:
+#  Avi Kivity <avi@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2 or
+# later.  See the COPYING file in the top-level directory.
+
+# 'qemu mtree' -- display the memory hierarchy
+
+import gdb
+
+def isnull(ptr):
+    return ptr == gdb.Value(0).cast(ptr.type)
+
+def int128(p):
+    '''Read an Int128 type to a python integer.
+
+    QEMU can be built with native Int128 support so we need to detect
+    if the value is a structure or the native type.
+    '''
+    if p.type.code == gdb.TYPE_CODE_STRUCT:
+        return int(p['lo']) + (int(p['hi']) << 64)
+    else:
+        return int(("%s" % p), 16)
+
+class MtreeCommand(gdb.Command):
+    '''Display the memory tree hierarchy'''
+    def __init__(self):
+        gdb.Command.__init__(self, 'qemu mtree', gdb.COMMAND_DATA,
+                             gdb.COMPLETE_NONE)
+        self.queue = []
+    def invoke(self, arg, from_tty):
+        self.seen = set()
+        self.queue_root('address_space_memory')
+        self.queue_root('address_space_io')
+        self.process_queue()
+    def queue_root(self, varname):
+        ptr = gdb.parse_and_eval(varname)['root']
+        self.queue.append(ptr)
+    def process_queue(self):
+        while self.queue:
+            ptr = self.queue.pop(0)
+            if int(ptr) in self.seen:
+                continue
+            self.print_item(ptr)
+    def print_item(self, ptr, offset = gdb.Value(0), level = 0):
+        self.seen.add(int(ptr))
+        addr = ptr['addr']
+        addr += offset
+        size = int128(ptr['size'])
+        alias = ptr['alias']
+        klass = ''
+        if not isnull(alias):
+            klass = ' (alias)'
+        elif not isnull(ptr['ops']):
+            klass = ' (I/O)'
+        elif bool(ptr['ram']):
+            klass = ' (RAM)'
+        gdb.write('%s%016x-%016x %s%s (@ %s)\n'
+                  % ('  ' * level,
+                     int(addr),
+                     int(addr + (size - 1)),
+                     ptr['name'].string(),
+                     klass,
+                     ptr,
+                     ),
+                  gdb.STDOUT)
+        if not isnull(alias):
+            gdb.write('%s    alias: %s@%016x (@ %s)\n' %
+                      ('  ' * level,
+                       alias['name'].string(),
+                       int(ptr['alias_offset']),
+                       alias,
+                       ),
+                      gdb.STDOUT)
+            self.queue.append(alias)
+        subregion = ptr['subregions']['tqh_first']
+        level += 1
+        while not isnull(subregion):
+            self.print_item(subregion, addr, level)
+            subregion = subregion['subregions_link']['tqe_next']