Fix pyocf Ctx ownership

Signed-off-by: Jan Musial <jan.musial@intel.com>

tests/functional/pyocf/types/cache.py

@@ -37,6 +37,7 @@ from .queue import Queue
 from .stats.cache import CacheInfo
 from .ioclass import IoClassesInfo, IoClassInfo
 from .stats.shared import UsageStats, RequestsStats, BlocksStats, ErrorsStats
+from .ctx import OcfCtx
 
 
 class Backfill(Structure):
@@ -474,7 +475,7 @@ class Cache:
 
         c = OcfCompletion([("cache", c_void_p), ("priv", c_void_p), ("error", c_int)])
 
-        device.owner.lib.ocf_mngt_cache_attach(
+        self.owner.lib.ocf_mngt_cache_attach(
             self.cache_handle, byref(self.dev_cfg), c, None
         )
 
@@ -500,7 +501,7 @@ class Cache:
     def load_cache(self, device, open_cores=True):
         self.configure_device(device, open_cores=open_cores)
         c = OcfCompletion([("cache", c_void_p), ("priv", c_void_p), ("error", c_int)])
-        device.owner.lib.ocf_mngt_cache_load(
+        self.owner.lib.ocf_mngt_cache_load(
             self.cache_handle, byref(self.dev_cfg), c, None
         )
 
@@ -509,8 +510,11 @@ class Cache:
             raise OcfError("Loading cache device failed", c.results["error"])
 
     @classmethod
-    def load_from_device(cls, device, name="cache", open_cores=True):
-        c = cls(name=name, owner=device.owner)
+    def load_from_device(cls, device, owner=None, name="cache", open_cores=True):
+        if owner is None:
+            owner = OcfCtx.get_default()
+
+        c = cls(name=name, owner=owner)
 
         c.start_cache()
         try:
@@ -522,8 +526,11 @@ class Cache:
         return c
 
     @classmethod
-    def start_on_device(cls, device, **kwargs):
-        c = cls(owner=device.owner, **kwargs)
+    def start_on_device(cls, device, owner=None, **kwargs):
+        if owner is None:
+            owner = OcfCtx.get_default()
+
+        c = cls(owner=owner, **kwargs)
 
         c.start_cache()
         try:

tests/functional/pyocf/types/ctx.py

@@ -4,6 +4,7 @@
 #
 
 from ctypes import c_void_p, Structure, c_char_p, cast, pointer, byref, c_int
+import weakref
 
 from .logger import LoggerOps, Logger
 from .data import DataOps, Data
@@ -27,6 +28,8 @@ class OcfCtxCfg(Structure):
 
 
 class OcfCtx:
+    default = None
+
     def __init__(self, lib, name, logger, data, cleaner):
         self.logger = logger
         self.data = data
@@ -51,10 +54,29 @@ class OcfCtx:
         if result != 0:
             raise OcfError("Context initialization failed", result)
 
+        if self.default is None or self.default() is None:
+            type(self).default = weakref.ref(self)
+
+    @classmethod
+    def with_defaults(cls, logger):
+        return cls(
+            OcfLib.getInstance(),
+            b"PyOCF default ctx",
+            logger,
+            Data,
+            Cleaner,
+        )
+
+    @classmethod
+    def get_default(cls):
+        if cls.default is None or cls.default() is None:
+            raise Exception("No context instantiated yet")
+
+        return cls.default()
+
     def register_volume_type(self, volume_type):
         self.volume_types[self.volume_types_count] = volume_type
         volume_type.type_id = self.volume_types_count
-        volume_type.owner = self
 
         result = self.lib.ocf_ctx_register_volume_type(
             self.ctx_handle,
@@ -90,26 +112,8 @@ class OcfCtx:
         self.cleanup_volume_types()
 
         self.lib.ocf_ctx_put(self.ctx_handle)
-
-        self.cfg = None
-        self.logger = None
-        self.data = None
-        self.cleaner = None
-        Queue._instances_ = {}
-        Volume._instances_ = {}
-        Volume._uuid_ = {}
-        Data._instances_ = {}
-        Logger._instances_ = {}
-
-
-def get_default_ctx(logger):
-    return OcfCtx(
-        OcfLib.getInstance(),
-        b"PyOCF default ctx",
-        logger,
-        Data,
-        Cleaner,
-    )
+        if type(self).default and type(self).default() == self:
+            type(self).default = None
 
 
 lib = OcfLib.getInstance()

tests/functional/tests/conftest.py

@@ -11,7 +11,7 @@ import gc
 sys.path.append(os.path.join(os.path.dirname(__file__), os.path.pardir))
 from pyocf.types.logger import LogLevel, DefaultLogger, BufferLogger
 from pyocf.types.volume import Volume, ErrorDevice
-from pyocf.types.ctx import get_default_ctx
+from pyocf.types.ctx import OcfCtx
 
 
 def pytest_configure(config):
@@ -20,7 +20,7 @@ def pytest_configure(config):
 
 @pytest.fixture()
 def pyocf_ctx():
-    c = get_default_ctx(DefaultLogger(LogLevel.WARN))
+    c = OcfCtx.with_defaults(DefaultLogger(LogLevel.WARN))
     c.register_volume_type(Volume)
     c.register_volume_type(ErrorDevice)
     yield c
@@ -31,7 +31,7 @@ def pyocf_ctx():
 @pytest.fixture()
 def pyocf_ctx_log_buffer():
     logger = BufferLogger(LogLevel.DEBUG)
-    c = get_default_ctx(logger)
+    c = OcfCtx.with_defaults(logger)
     c.register_volume_type(Volume)
     c.register_volume_type(ErrorDevice)
     yield logger