Recursively mount root dataset during boot if it is not encrypted (#1…

…3553)

Import the pools during boot without mounting any of the datasets.
Check on 'feature@encryption' for imported pool. If feature is not
active, recursively mount the root datasets, which effectively
mounts all datasets present on the pool.

If the encryption feature is active, continue and unlock the
datasets.

Signed-off-by: Umer Saleem <usaleem@ixsystems.com>

src/middlewared/middlewared/plugins/pool_/import_pool.py

@@ -212,13 +212,67 @@ async def import_pool(self, job, data):
 
         return True
 
+    @private
+    def recursive_mount(self, name):
+        cmd = [
+            'zfs', 'mount',
+            '-R',  # recursive flag
+            name,  # name of the zpool / root dataset
+        ]
+        try:
+            self.logger.debug('Going to mount root dataset recusively: %r', name)
+            cp = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+            if cp.returncode != 0:
+                self.logger.error(
+                    'Failed to mount datasets for pool: %r with error: %r',
+                    name, cp.stdout.decode()
+                )
+                return False
+            return True
+        except Exception:
+            self.logger.error(
+                'Unhandled exception while mounting datasets for pool: %r',
+                name, exc_info=True
+            )
+            return False
+
+    @private
+    def encryption_is_active(self, name):
+        cmd = [
+            'zpool', 'get',
+            '-H',                 # use in script
+            '-o', 'value',        # retrieve the value
+            'feature@encryption', # property to retrieve
+            name,                 # name of the zpool
+        ]
+        try:
+            self.logger.debug('Checking if feature@encryption is active on pool: %r', name)
+            cp = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+            if cp.returncode != 0:
+                self.logger.error(
+                    'Failed to get feature@encryption for pool: %r with error: %r',
+                    name, cp.stdout.decode()
+                )
+                return False
+            if cp.stdout.decode().strip() == 'active':
+                return True
+            else:
+                return False
+        except Exception:
+            self.logger.error(
+                'Unhandled exception while checking on feature@encryption for pool: %r',
+                name, exc_info=True
+            )
+            return False
+
     @private
     def import_on_boot_impl(self, vol_name, vol_guid, set_cachefile=False):
         cmd = [
             'zpool', 'import',
             vol_guid,  # the GUID of the zpool
             '-R', '/mnt',  # altroot
             '-m',  # import pool with missing log device(s)
+            '-N',  # do not mount the datasets
             '-f',  # force import since hostid can change (upgrade from CORE to SCALE changes it, for example)
             '-o', f'cachefile={ZPOOL_CACHE_FILE}' if set_cachefile else 'cachefile=none',
         ]
@@ -421,6 +475,10 @@ def import_on_boot(self, job):
             if not self.import_on_boot_impl(name, guid, set_cachefile_property):
                 continue
 
+            if not self.encryption_is_active(name):
+                self.recursive_mount(name)
+                continue
+
             self.unlock_on_boot_impl(name)
 
         # no reason to wait on this to complete