1#
2# gdb helper commands and functions for Linux kernel debugging
3#
4#  module tools
5#
6# Copyright (c) Siemens AG, 2013
7#
8# Authors:
9#  Jan Kiszka <jan.kiszka@siemens.com>
10#
11# This work is licensed under the terms of the GNU GPL version 2.
12#
13
14import gdb
15
16from linux import cpus, utils
17
18
19module_type = utils.CachedType("struct module")
20
21
22def module_list():
23    global module_type
24    module_ptr_type = module_type.get_type().pointer()
25    modules = gdb.parse_and_eval("modules")
26    entry = modules['next']
27    end_of_list = modules.address
28
29    while entry != end_of_list:
30        yield utils.container_of(entry, module_ptr_type, "list")
31        entry = entry['next']
32
33
34def find_module_by_name(name):
35    for module in module_list():
36        if module['name'].string() == name:
37            return module
38    return None
39
40
41class LxModule(gdb.Function):
42    """Find module by name and return the module variable.
43
44$lx_module("MODULE"): Given the name MODULE, iterate over all loaded modules
45of the target and return that module variable which MODULE matches."""
46
47    def __init__(self):
48        super(LxModule, self).__init__("lx_module")
49
50    def invoke(self, mod_name):
51        mod_name = mod_name.string()
52        module = find_module_by_name(mod_name)
53        if module:
54            return module.dereference()
55        else:
56            raise gdb.GdbError("Unable to find MODULE " + mod_name)
57
58
59LxModule()
60
61
62class LxLsmod(gdb.Command):
63    """List currently loaded modules."""
64
65    _module_use_type = utils.CachedType("struct module_use")
66
67    def __init__(self):
68        super(LxLsmod, self).__init__("lx-lsmod", gdb.COMMAND_DATA)
69
70    def invoke(self, arg, from_tty):
71        gdb.write(
72            "Address{0}    Module                  Size  Used by\n".format(
73                "        " if utils.get_long_type().sizeof == 8 else ""))
74
75        for module in module_list():
76            gdb.write("{address} {name:<19} {size:>8}  {ref}".format(
77                address=str(module['module_core']).split()[0],
78                name=module['name'].string(),
79                size=str(module['core_size']),
80                ref=str(module['refcnt']['counter'])))
81
82            source_list = module['source_list']
83            t = self._module_use_type.get_type().pointer()
84            entry = source_list['next']
85            first = True
86            while entry != source_list.address:
87                use = utils.container_of(entry, t, "source_list")
88                gdb.write("{separator}{name}".format(
89                    separator=" " if first else ",",
90                    name=use['source']['name'].string()))
91                first = False
92                entry = entry['next']
93            gdb.write("\n")
94
95
96LxLsmod()
97