scripts/qemu-gdb: Split MtreeCommand into its own module

As we add more commands to our Python gdb debugging support, it's
going to get unwieldy to have everything in a single file. Split
the implementation of the 'mtree' command from qemu-gdb.py into
its own module.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1439574392-4403-2-git-send-email-peter.maydell@linaro.org

2 files changed, 110 insertions, 0 deletions

diff --git a/scripts/qemugdb/__init__.py b/scripts/qemugdb/__init__.py
new file mode 100644
index 0000000000..969f552b26
--- /dev/null
+++ b/scripts/qemugdb/__init__.py
@@ -0,0 +1,28 @@
+#!/usr/bin/python
+
+# GDB debugging support
+#
+# Copyright (c) 2015 Linaro Ltd
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, see
+# <http://www.gnu.org/licenses/gpl-2.0.html>
+#
+
+# We don't need to do anything in our init file currently.
+
+"""
+Support routines for debugging QEMU under GDB
+"""
+
+__license__    = "GPL version 2 or (at your option) any later version"
diff --git a/scripts/qemugdb/mtree.py b/scripts/qemugdb/mtree.py
new file mode 100644
index 0000000000..06011c30cc
--- /dev/null
+++ b/scripts/qemugdb/mtree.py
@@ -0,0 +1,82 @@
+#!/usr/bin/python
+
+# 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.  See
+# the COPYING file in the top-level directory.
+#
+# Contributions after 2012-01-13 are licensed under the terms of the
+# GNU GPL, version 2 or (at your option) any later version.
+
+# 'qemu mtree' -- display the memory hierarchy
+
+import gdb
+
+def isnull(ptr):
+    return ptr == gdb.Value(0).cast(ptr.type)
+
+def int128(p):
+    return long(p['lo']) + (long(p['hi']) << 64)
+
+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 long(ptr) in self.seen:
+                continue
+            self.print_item(ptr)
+    def print_item(self, ptr, offset = gdb.Value(0), level = 0):
+        self.seen.add(long(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,
+                     long(addr),
+                     long(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(),
+                       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']
+