From 53187795838ccee4b470f3a08aeaf6e474975408 Mon Sep 17 00:00:00 2001
From: Venky Shankar <vshankar@redhat.com>
Date: Mon, 2 Dec 2019 01:56:25 -0500
Subject: [PATCH] mgr/volumes: module to track pending clone operations

Signed-off-by: Venky Shankar <vshankar@redhat.com>
---
 src/pybind/mgr/volumes/fs/exception.py        |  8 +++
 .../mgr/volumes/fs/operations/clone_index.py  | 62 +++++++++++++++++++
 src/pybind/mgr/volumes/fs/operations/index.py | 21 +++++++
 .../fs/operations/versions/subvolume_base.py  |  2 +-
 .../fs/operations/versions/subvolume_v1.py    |  2 +-
 5 files changed, 93 insertions(+), 2 deletions(-)
 create mode 100644 src/pybind/mgr/volumes/fs/operations/clone_index.py
 create mode 100644 src/pybind/mgr/volumes/fs/operations/index.py

diff --git a/src/pybind/mgr/volumes/fs/exception.py b/src/pybind/mgr/volumes/fs/exception.py
index 4493141d0a0..841b35202ee 100644
--- a/src/pybind/mgr/volumes/fs/exception.py
+++ b/src/pybind/mgr/volumes/fs/exception.py
@@ -17,6 +17,14 @@ class MetadataMgrException(Exception):
     def __str__(self):
         return "{0} ({1})".format(self.errno, self.error_str)
 
+class IndexException(Exception):
+    def __init__(self, error_code, error_message):
+        self.errno = error_code
+        self.error_str = error_message
+
+    def __str__(self):
+        return "{0} ({1})".format(self.errno, self.error_str)
+
 class OpSmException(Exception):
     def __init__(self, error_code, error_message):
         self.errno = error_code
diff --git a/src/pybind/mgr/volumes/fs/operations/clone_index.py b/src/pybind/mgr/volumes/fs/operations/clone_index.py
new file mode 100644
index 00000000000..2e25af1763f
--- /dev/null
+++ b/src/pybind/mgr/volumes/fs/operations/clone_index.py
@@ -0,0 +1,62 @@
+import os
+import uuid
+import stat
+import errno
+import logging
+from contextlib import contextmanager
+
+import cephfs
+
+from .index import Index
+from ..exception import IndexException, VolumeException
+
+log = logging.getLogger(__name__)
+
+class CloneIndex(Index):
+    SUB_GROUP_NAME = "clone"
+
+    @property
+    def path(self):
+        return os.path.join(super(CloneIndex, self).path, CloneIndex.SUB_GROUP_NAME.encode('utf-8'))
+
+    def _track(self, sink_path):
+        tracking_id = str(uuid.uuid4())
+        source_path = os.path.join(self.path, tracking_id.encode('utf-8'))
+        log.info("tracking-id {0} for path {1}".format(tracking_id, sink_path))
+
+        self.fs.symlink(sink_path, source_path)
+        return tracking_id
+
+    def track(self, sink_path):
+        try:
+            return self._track(sink_path)
+        except (VolumeException, cephfs.Error) as e:
+            if isinstance(e, cephfs.Error):
+                e = IndexException(-e.args[0], e.args[1])
+            elif isinstance(VolumeException, e):
+                e = IndexException(e.errno, e.error_str)
+            raise e
+
+    def untrack(self, tracking_id):
+        log.info("untracking {0}".format(tracking_id))
+        source_path = os.path.join(self.path, tracking_id.encode('utf-8'))
+        try:
+            self.fs.unlink(source_path)
+        except cephfs.Error as e:
+            raise IndexException(-e.args[0], e.args[1])
+
+def create_clone_index(fs, vol_spec):
+    clone_index = CloneIndex(fs, vol_spec)
+    try:
+        fs.mkdirs(clone_index.path, 0o700)
+    except cephfs.Error as e:
+        raise IndexException(-e.args[0], e.args[1])
+
+@contextmanager
+def open_clone_index(fs, vol_spec):
+    clone_index = CloneIndex(fs, vol_spec)
+    try:
+        fs.stat(clone_index.path)
+    except cephfs.Error as e:
+        raise IndexException(-e.args[0], e.args[1])
+    yield clone_index
diff --git a/src/pybind/mgr/volumes/fs/operations/index.py b/src/pybind/mgr/volumes/fs/operations/index.py
new file mode 100644
index 00000000000..783564c067b
--- /dev/null
+++ b/src/pybind/mgr/volumes/fs/operations/index.py
@@ -0,0 +1,21 @@
+import os
+
+from .template import GroupTemplate
+
+class Index(GroupTemplate):
+    GROUP_NAME = "_index"
+
+    def __init__(self, fs, vol_spec):
+        self.fs = fs
+        self.vol_spec = vol_spec
+        self.groupname = Index.GROUP_NAME
+
+    @property
+    def path(self):
+        return os.path.join(self.vol_spec.base_dir.encode('utf-8'), self.groupname.encode('utf-8'))
+
+    def track(self, *args):
+        raise VolumeException(-errno.EINVAL, "operation not supported.")
+
+    def untrack(self, tracking_id):
+        raise VolumeException(-errno.EINVAL, "operation not supported.")
diff --git a/src/pybind/mgr/volumes/fs/operations/versions/subvolume_base.py b/src/pybind/mgr/volumes/fs/operations/versions/subvolume_base.py
index d1db4baca0b..d6d91f410f6 100644
--- a/src/pybind/mgr/volumes/fs/operations/versions/subvolume_base.py
+++ b/src/pybind/mgr/volumes/fs/operations/versions/subvolume_base.py
@@ -63,7 +63,7 @@ class SubvolumeBase(object):
         else:
             self.metadata_mgr = MetadataManager(self.fs, self.config_path, 0o640)
 
-    def _set_attrs(self, path, size, isolate_namespace, pool, mode, uid, gid):
+    def _set_attrs(self, path, size, isolate_namespace, pool, uid, gid):
         # set size
         if size is not None:
             try:
diff --git a/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v1.py b/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v1.py
index 762ea4a47a8..45947eb5743 100644
--- a/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v1.py
+++ b/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v1.py
@@ -40,7 +40,7 @@ class SubvolumeV1(SubvolumeBase, SubvolumeTemplate):
         try:
             # create directory and set attributes
             self.fs.mkdirs(subvol_path, mode)
-            self._set_attrs(subvol_path, size, isolate_nspace, pool, mode, uid, gid)
+            self._set_attrs(subvol_path, size, isolate_nspace, pool, uid, gid)
 
             # persist subvolume metadata
             qpath = subvol_path.decode('utf-8')
-- 
2.39.5