mgr/vol: handle snaps when multiple incarnation exists

When a directory for previous incarnation exists for a subvolume along
with its current incarnation, check all incarnaitions for existence of
a snapshot with given name.

Signed-off-by: Rishabh Dave <ridave@redhat.com>

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 506796a583f89d2da6477a481f8d27dd172cc154..cf18888c42799958d6b12bc0edc0f0f98a915dda 100644 (file)
--- a/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v1.py
+++ b/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v1.py
@@ -801,10 +801,10 @@ class SubvolumeV1(SubvolumeBase, SubvolumeTemplate):
 
         return pending_clones_info
 
-    def remove_snapshot(self, snapname, force=False):
+    def remove_snapshot(self, snapname, force=False, uuid=None):
         if self.has_pending_clones(snapname):
             raise VolumeException(-errno.EAGAIN, "snapshot '{0}' has pending clones".format(snapname))
-        snappath = self.snapshot_path(snapname)
+        snappath = self.snapshot_path(snapname, uuid=uuid)
         try:
             self.metadata_mgr.remove_section(self.get_snap_section_name(snapname))
             self.metadata_mgr.flush()

diff --git a/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v2.py b/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v2.py
index d23d326c567abf00f0491ed8aadfb1561e049971..b72a6ceb03bef1a05ae4de24482393b5eb06a59a 100644 (file)
--- a/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v2.py
+++ b/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v2.py
@@ -414,8 +414,11 @@ class SubvolumeV2(SubvolumeV1):
 
         return {'type': self.subvol_type.value, 'features': self.features, 'state': SubvolumeStates.STATE_RETAINED.value}
 
-    def remove_snapshot(self, snapname, force=False):
-        super(SubvolumeV2, self).remove_snapshot(snapname, force)
+    def create_snapshot(self, snap_name):
+        super(SubvolumeV2, self).create_snapshot(snap_name)
+
+    def remove_snapshot(self, snapname, force=False, uuid=None):
+        super(SubvolumeV2, self).remove_snapshot(snapname, force=force, uuid=uuid)
         if self.purgeable:
             self.trash_base_dir()
             # tickle the volume purge job to purge this entry, using ESTALE

diff --git a/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v3.py b/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v3.py
index 597e4b3c3cc8f3a8de921f3b4bc54166492e669d..0152eedac250900c7418272d8be10e8889316a1c 100644 (file)
--- a/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v3.py
+++ b/src/pybind/mgr/volumes/fs/operations/versions/subvolume_v3.py
@@ -227,9 +227,57 @@ class SubvolumeV3(SubvolumeV2):
     # following are methods that help or do snapshot creation
 
 
+    def snapshot_path(self, snap_name, uuid=None):
+        '''
+        Path to a specific snapshot named 'snap_name'.
+        '''
+        if uuid:
+            return join(self.roots_dir, uuid,
+                        self.vol_spec.snapshot_prefix.encode('utf-8'),
+                        snap_name.encode('utf-8'))
+        else:
+            return join(self.snapshot_base_path(), snap_name.encode('utf-8'))
+
     def snapshot_base_path(self):
         return self.snap_dir
 
+    def get_incar_uuid_for_snap(self, snap_name):
+        '''
+        Return incarnation's UUID in which the snapshot name is present.
+        When multiple incarnations for a subvolume exists, check if a snap
+        exists in one of the incarnations.
+        '''
+        # list of all incarnations/UUID dirs of this subvolume.
+        incars = listdir(self.fs, self.roots_dir)
+
+        for incar_uuid in incars:
+            # construct path to ".snap" directory for given UUID.
+            snap_dir = join(self.roots_dir, incar_uuid,
+                            self.vol_spec.snapshot_dir_prefix.encode('utf-8'))
+            all_snap_names = listdir(self.fs, snap_dir)
+            # encode since listdir() call above returns list of bytes and list
+            # of str
+            if snap_name.encode('utf-8') in all_snap_names:
+                return incar_uuid
+
+        return None
+
+    def create_snapshot(self, snap_name):
+        if self.get_incar_uuid_for_snap(snap_name) != None:
+            raise VolumeException(errno.EEXIST,
+                                  f'subvolume \'{snap_name}\' already exists')
+
+        super(SubvolumeV3, self).create_snapshot(snap_name)
+
+    def remove_snapshot(self, snap_name, force):
+        uuid = self.get_incar_uuid_for_snap(snap_name)
+        if uuid == None:
+            raise VolumeException(errno.ENOENT,
+                                  f'subvolume \'{snap_name}\' does not exists')
+
+        super(SubvolumeV3, self).remove_snapshot(snap_name, force=force,
+                                                 uuid=uuid)
+
     def remove_but_retain_snaps(self):
         assert self.state != SubvolumeStates.STATE_RETAINED
 
@@ -242,7 +290,6 @@ class SubvolumeV3(SubvolumeV2):
         except MetadataMgrException as e:
             log.error(f"failed to write config: {e}")
             raise VolumeException(e.args[0], e.args[1])
-
     # in subvol v3, self.mnt_dir (AKA data dir) is renamed to ".unlinked" if
     # subvol is deleted but snapshots are retained.
     def trash_incarnation_dir(self):
@@ -258,6 +305,7 @@ class SubvolumeV3(SubvolumeV2):
             SubvolumeStates.STATE_RETAINED.value)
         self.metadata_mgr.flush()
 
+
     # Following methods help clone operation -