Add helper commands and functions for finding pointers to struct device
by enumerating linux device bus/class infrastructure. This can be used
to fetch subsystem and driver-specific structs:
(gdb) p *$container_of($lx_device_find_by_class_name("net", "eth0"), "struct
net_device", "dev")
(gdb) p *$container_of($lx_device_find_by_bus_name("i2c", "0-004b"), "struct
i2c_client", "dev")
(gdb) p *(struct imx_port*)$lx_device_find_by_class_name("tty",
"ttymxc1")->parent->driver_data
Several generic "lx-device-list" functions are included to enumerate
devices by bus and class:
(gdb) lx-device-list-bus usb
(gdb) lx-device-list-class
(gdb) lx-device-list-tree _bus
Similar information is available in /sys but pointer values are
deliberately hidden.
Signed-off-by: Leonard Crestez
---
scripts/gdb/linux/device.py | 182
scripts/gdb/vmlinux-gdb.py | 1 +
2 files changed, 183 insertions(+)
create mode 100644 scripts/gdb/linux/device.py
diff --git a/scripts/gdb/linux/device.py b/scripts/gdb/linux/device.py
new file mode 100644
index ..16376c5cfec6
--- /dev/null
+++ b/scripts/gdb/linux/device.py
@@ -0,0 +1,182 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (c) NXP 2019
+
+import gdb
+
+from linux.utils import CachedType
+from linux.utils import container_of
+from linux.lists import list_for_each_entry
+
+
+device_private_type = CachedType('struct device_private')
+device_type = CachedType('struct device')
+
+subsys_private_type = CachedType('struct subsys_private')
+kobject_type = CachedType('struct kobject')
+kset_type = CachedType('struct kset')
+
+bus_type = CachedType('struct bus_type')
+class_type = CachedType('struct class')
+
+
+def dev_name(dev):
+dev_init_name = dev['init_name']
+if dev_init_name:
+return dev_init_name.string()
+return dev['kobj']['name'].string()
+
+
+def kset_for_each_object(kset):
+return list_for_each_entry(kset['list'],
+kobject_type.get_type().pointer(), "entry")
+
+
+def for_each_bus():
+for kobj in kset_for_each_object(gdb.parse_and_eval('bus_kset')):
+subsys = container_of(kobj, kset_type.get_type().pointer(), 'kobj')
+subsys_priv = container_of(subsys,
subsys_private_type.get_type().pointer(), 'subsys')
+yield subsys_priv['bus']
+
+
+def for_each_class():
+for kobj in kset_for_each_object(gdb.parse_and_eval('class_kset')):
+subsys = container_of(kobj, kset_type.get_type().pointer(), 'kobj')
+subsys_priv = container_of(subsys,
subsys_private_type.get_type().pointer(), 'subsys')
+yield subsys_priv['class']
+
+
+def get_bus_by_name(name):
+for item in for_each_bus():
+if item['name'].string() == name:
+return item
+raise gdb.GdbError("Can't find bus type {!r}".format(name))
+
+
+def get_class_by_name(name):
+for item in for_each_class():
+if item['name'].string() == name:
+return item
+raise gdb.GdbError("Can't find device class {!r}".format(name))
+
+
+klist_type = CachedType('struct klist')
+klist_node_type = CachedType('struct klist_node')
+
+
+def klist_for_each(klist):
+return list_for_each_entry(klist['k_list'],
+klist_node_type.get_type().pointer(), 'n_node')
+
+
+def bus_for_each_device(bus):
+for kn in klist_for_each(bus['p']['klist_devices']):
+dp = container_of(kn, device_private_type.get_type().pointer(),
'knode_bus')
+yield dp['device']
+
+
+def class_for_each_device(cls):
+for kn in klist_for_each(cls['p']['klist_devices']):
+dp = container_of(kn, device_private_type.get_type().pointer(),
'knode_class')
+yield dp['device']
+
+
+def device_for_each_child(dev):
+for kn in klist_for_each(dev['p']['klist_children']):
+dp = container_of(kn, device_private_type.get_type().pointer(),
'knode_parent')
+yield dp['device']
+
+
+def _show_device(dev, level=0, recursive=False):
+gdb.write('{}dev {}:\t{}\n'.format('\t' * level, dev_name(dev), dev))
+if recursive:
+for child in device_for_each_child(dev):
+_show_device(child, level + 1, recursive)
+
+
+class LxDeviceListBus(gdb.Command):
+'''Print devices on a bus (or all buses if not specified)'''
+
+def __init__(self):
+super(LxDeviceListBus, self).__init__('lx-device-list-bus',
gdb.COMMAND_DATA)
+
+def invoke(self, arg, from_tty):
+if not arg:
+for bus in for_each_bus():
+gdb.write('bus {}:\t{}\n'.format(bus['name'].string(), bus))
+for dev in bus_for_each_device(bus):
+_show_device(dev, level=1)
+else:
+bus = get_bus_by_name(arg)
+if not bus:
+raise gdb.GdbError("Can't find bus {!r}".format(arg))
+for dev in bus_for_each_device(bus):
+_show_device(dev)
+
+
+class LxDeviceListClass(gdb.Command):
+'''Print devices in a class (or all classes if
