Speed up device query

qubes/device_protocol.py

@@ -858,18 +858,23 @@ def _load_classes(cls, bus: str):
             subclass_id = None
             for line in pciids.readlines():
                 line = line.rstrip()
+                if not line:
+                    continue
+                first_char = line[0]
                 if (
-                    line.startswith("\t\t")
+                    first_char == "\t"
+                    and len(line) >= 2
+                    and line[1] == "\t"
                     and class_id is not None
                     and subclass_id is not None
                 ):
                     progif_id, _, progif_name = line[2:].split(" ", 2)
                     result[class_id + subclass_id + progif_id] = progif_name
-                elif line.startswith("\t") and class_id:
+                elif first_char == "\t" and class_id:
                     subclass_id, _, subclass_name = line[1:].split(" ", 2)
                     # store both prog-if specific entry and generic one
                     result[class_id + subclass_id + "**"] = subclass_name
-                elif line.startswith("C "):
+                elif first_char == "C" and len(line) >= 2 and line[1] == " ":
                     _, class_id, _, class_name = line.split(" ", 3)
                     result[class_id + "****"] = class_name
                     subclass_id = None

qubes/events.py

@@ -160,7 +160,7 @@ def _fire_event(self, event, kwargs, pre_event=False):
                 h_func
                 for h_name, h_func_set in handlers_dict.items()
                 for h_func in h_func_set
-                if fnmatch.fnmatch(event, h_name)
+                if fnmatch.fnmatchcase(event, h_name)
             ]
             for func in sorted(
                 handlers,

qubes/ext/block.py

@@ -230,11 +230,8 @@ def attachment(self) -> Optional[QubesVM]:
     def _is_attached_to(self, vm):
         xml_desc = lxml.etree.fromstring(vm.libvirt_domain.XMLDesc())
 
-        for disk in xml_desc.findall("devices/disk"):
-            info = _try_get_block_device_info(vm.app, disk)
-            if not info:
-                continue
-            backend_domain, port_id = info
+        for disk in xml_desc.findall("devices/disk[source][@type='block']"):
+            backend_domain, port_id = _try_get_block_device_info(vm.app, disk)
 
             if backend_domain.name != self.backend_domain.name:
                 continue
@@ -288,18 +285,13 @@ def _sanitize(
 
 
 def _try_get_block_device_info(app, disk):
-    if disk.get("type") != "block":
-        return None
-    dev_path_node = disk.find("source")
-    if dev_path_node is None:
-        return None
-
     backend_domain_node = disk.find("backenddomain")
     if backend_domain_node is not None:
         backend_domain = app.domains[backend_domain_node.get("name")]
     else:
         backend_domain = app.domains[0]
 
+    dev_path_node = disk.find("source")
     dev_path = dev_path_node.get("dev")
 
     if dev_path.startswith("/dev/"):
@@ -357,11 +349,10 @@ def get_device_attachments(vm_):
 
             xml_desc = lxml.etree.fromstring(vm.libvirt_domain.XMLDesc())
 
-            for disk in xml_desc.findall("devices/disk"):
-                info = _try_get_block_device_info(vm.app, disk)
-                if not info:
-                    continue
-                backend_domain, port_id = info
+            for disk in xml_desc.findall("devices/disk[source][@type='block']"):
+                backend_domain, port_id = _try_get_block_device_info(
+                    vm.app, disk
+                )
                 if backend_domain != vm_:
                     continue
 
@@ -434,29 +425,16 @@ def on_device_list_attached(self, vm, event, **kwargs):
             system_disks = SYSTEM_DISKS_DOM0_KERNEL
         xml_desc = lxml.etree.fromstring(vm.libvirt_domain.XMLDesc())
 
-        for disk in xml_desc.findall("devices/disk"):
-            if disk.get("type") != "block":
-                continue
-            dev_path_node = disk.find("source")
-            if dev_path_node is None:
-                continue
-            dev_path = dev_path_node.get("dev")
-
+        for disk in xml_desc.findall(
+            "devices/disk[source][target][@type='block']"
+        ):
+            backend_domain, port_id = _try_get_block_device_info(vm.app, disk)
             target_node = disk.find("target")
-            if target_node is not None:
-                frontend_dev = target_node.get("dev")
-                if not frontend_dev:
-                    continue
-                if frontend_dev in system_disks:
-                    continue
-            else:
+            frontend_dev = target_node.get("dev")
+            if not frontend_dev:
+                continue
+            if frontend_dev in system_disks:
                 continue
-
-            backend_domain_node = disk.find("backenddomain")
-            if backend_domain_node is not None:
-                backend_domain = vm.app.domains[backend_domain_node.get("name")]
-            else:
-                backend_domain = vm.app.domains[0]
 
             options = {}
             read_only_node = disk.find("readonly")
@@ -465,15 +443,9 @@ def on_device_list_attached(self, vm, event, **kwargs):
             else:
                 options["read-only"] = "no"
             options["frontend-dev"] = frontend_dev
-            if disk.get("device") != "disk":
-                options["devtype"] = disk.get("device")
-
-            if dev_path.startswith("/dev/"):
-                port_id = dev_path[len("/dev/") :]
-            else:
-                port_id = dev_path
-
-            port_id = port_id.replace("/", "_")
+            devtype = disk.get("device")
+            if devtype != "disk":
+                options["devtype"] = devtype
 
             yield BlockDevice(Port(backend_domain, port_id, "block")), options
 

qubes/ext/pci.py

@@ -64,15 +64,24 @@ def load_pci_classes():
         subclass_id = None
         for line in pciids.readlines():
             line = line.rstrip()
-            if line.startswith("\t\t") and class_id and subclass_id:
+            if not line:
+                continue
+            first_char = line[0]
+            if (
+                first_char == "\t"
+                and len(line) >= 2
+                and line[1] == "\t"
+                and class_id is not None
+                and subclass_id is not None
+            ):
                 progif_id, _, class_name = line[2:].split(" ", 2)
                 result[class_id + subclass_id + progif_id] = class_name
-            elif line.startswith("\t") and class_id:
+            elif first_char == "\t" and class_id:
                 subclass_id, _, class_name = line[1:].split(" ", 2)
                 # store both prog-if specific entry and generic one
                 result[class_id + subclass_id + "00"] = class_name
                 result[class_id + subclass_id] = class_name
-            elif line.startswith("C "):
+            elif first_char == "C" and len(line) >= 2 and line[1] == " ":
                 _, class_id, _, class_name = line.split(" ", 3)
                 result[class_id + "0000"] = class_name
                 result[class_id + "00"] = class_name
@@ -355,16 +364,11 @@ def __init__(self):
     @qubes.ext.handler("device-list:pci")
     def on_device_list_pci(self, vm, event):
         # pylint: disable=unused-argument
-        # only dom0 expose PCI devices
+        # only dom0 exposes PCI devices
         if vm.qid != 0:
             return
 
-        for dev in vm.app.vmm.libvirt_conn.listAllDevices():
-            if "pci" not in dev.listCaps():
-                continue
-
-            xml_desc = lxml.etree.fromstring(dev.XMLDesc())
-            libvirt_name = xml_desc.findtext("name")
+        for libvirt_name in vm.app.vmm.libvirt_conn.listDevices("pci"):
             try:
                 yield PCIDevice(
                     Port(backend_domain=vm, port_id=None, devclass="pci"),
@@ -388,14 +392,13 @@ def on_device_list_attached(self, vm, event, **kwargs):
             return
         xml_desc = lxml.etree.fromstring(vm.libvirt_domain.XMLDesc())
 
-        for hostdev in xml_desc.findall("devices/hostdev"):
-            if hostdev.get("type") != "pci":
-                continue
-            address = hostdev.find("source/address")
-            segment = address.get("domain")[2:]
-            bus = address.get("bus")[2:]
-            device = address.get("slot")[2:]
-            function = address.get("function")[2:]
+        for hostdev in xml_desc.findall(
+            "devices/hostdev[@type='pci']/source/address"
+        ):
+            segment = hostdev.get("domain")[2:]
+            bus = hostdev.get("bus")[2:]
+            device = hostdev.get("slot")[2:]
+            function = hostdev.get("function")[2:]
 
             libvirt_name = "pci_{segment}_{bus}_{device}_{function}".format(
                 segment=segment,

qubes/storage/__init__.py

@@ -657,24 +657,28 @@ def attach(self, volume, rw=False):
 
     def _is_already_attached(self, volume):
         """Checks if the given volume is already attached"""
+        # TODO: ben: cache
         parsed_xml = lxml.etree.fromstring(self.vm.libvirt_domain.XMLDesc())
-        disk_sources = parsed_xml.xpath("//domain/devices/disk/source")
-        for source in disk_sources:
-            if source.get("dev") == "/dev/%s" % volume.vid:
-                return True
+        disks = parsed_xml.xpath(
+            "//domain/devices/disk/source[@dev='/dev/$vid']", vid=volume.vid
+        )
+        if disks:
+            return True
         return False
 
     def detach(self, volume):
         """Detach a volume from domain"""
+        # TODO: ben: cache
         parsed_xml = lxml.etree.fromstring(self.vm.libvirt_domain.XMLDesc())
-        disks = parsed_xml.xpath("//domain/devices/disk")
-        for disk in disks:
-            source = disk.xpath("source")[0]
-            if source.get("dev") == "/dev/%s" % volume.vid:
-                disk_xml = lxml.etree.tostring(disk, encoding="utf-8")
-                self.vm.libvirt_domain.detachDevice(disk_xml)
-                return
-        raise StoragePoolException("Volume {!r} is not attached".format(volume))
+        disks = parsed_xml.xpath(
+            "//domain/devices/disk/source[@dev='/dev/$vid']", vid=volume.vid
+        )
+        if not disks:
+            raise StoragePoolException(
+                "Volume {!r} is not attached".format(volume)
+            )
+        disk_xml = lxml.etree.tostring(disks[0], encoding="utf-8")
+        self.vm.libvirt_domain.detachDevice(disk_xml)
 
     @property
     def kernels_dir(self):
@@ -878,11 +882,12 @@ def unused_frontend(self):
     @property
     def used_frontends(self):
         """Used device names"""
+        # TODO: ben: cache
         xml = self.vm.libvirt_domain.XMLDesc()
         parsed_xml = lxml.etree.fromstring(xml)
         return {
             target.get("dev", None)
-            for target in parsed_xml.xpath("//domain/devices/disk/target")
+            for target in parsed_xml.xpath("//domain/devices/disk/target[@dev]")
         }
 
     async def export(self, volume):

qubes/tests/devices_pci.py

@@ -52,8 +52,8 @@ def __hash__(self):
 
 
 PCI_XML = """<device>
-  <name>pci_{}_00_14_0</name>
-  <path>/sys/devices/pci{}:00/{}:00:14.0</path>
+  <name>pci_{address}_00_14_0</name>
+  <path>/sys/devices/pci{address}:00/{address}:00:14.0</path>
   <parent>computer</parent>
   <driver>
     <name>pciback</name>
@@ -196,25 +196,11 @@ def test_000_unsupported_device(self):
             **{
                 "vmm.offline_mode": False,
                 "vmm.libvirt_conn.nodeDeviceLookupByName.return_value": mock.Mock(
-                    **{"XMLDesc.return_value": PCI_XML.format(*["0000"] * 3)}
+                    **{"XMLDesc.return_value": PCI_XML.format(address="0000")}
                 ),
-                "vmm.libvirt_conn.listAllDevices.return_value": [
-                    mock.Mock(
-                        **{
-                            "XMLDesc.return_value": PCI_XML.format(
-                                *["0000"] * 3
-                            ),
-                            "listCaps.return_value": ["pci"],
-                        }
-                    ),
-                    mock.Mock(
-                        **{
-                            "XMLDesc.return_value": PCI_XML.format(
-                                *["10000"] * 3
-                            ),
-                            "listCaps.return_value": ["pci"],
-                        }
-                    ),
+                "vmm.libvirt_conn.listDevices.return_value": [
+                    "pci_0000_00_14_0",
+                    "pci_10000_00_14_0",
                 ],
             }
         )

qubes/utils.py

@@ -21,6 +21,7 @@
 #
 
 import asyncio
+import functools
 import hashlib
 import logging
 import re
@@ -177,6 +178,7 @@ def urandom(size):
     return hashlib.sha512(rand).digest()
 
 
+@functools.cache
 def get_entry_point_one(group, name):
     epoints = tuple(importlib.metadata.entry_points(group=group, name=name))
     if not epoints:

qubes/vm/qubesvm.py

@@ -1030,15 +1030,14 @@ def attached_volumes(self):
         result = []
         xml_desc = self.libvirt_domain.XMLDesc()
         xml = lxml.etree.fromstring(xml_desc)
-        for disk in xml.xpath("//domain/devices/disk"):
-            if disk.find("backenddomain") is not None:
-                pool_name = "p_%s" % disk.find("backenddomain").get("name")
-                pool = self.app.pools[pool_name]
-                vid = disk.find("source").get("dev").split("/dev/")[1]
-                for volume in pool.volumes:
-                    if volume.vid == vid:
-                        result += [volume]
-                        break
+        for disk in xml.xpath("//domain/devices/disk[source][backenddomain]"):
+            pool_name = "p_%s" % disk.find("backenddomain").get("name")
+            pool = self.app.pools[pool_name]
+            vid = disk.find("source").get("dev").split("/dev/")[1]
+            for volume in pool.volumes:
+                if volume.vid == vid:
+                    result += [volume]
+                    break
 
         return result + list(self.volumes.values())