From cc9eb1812e9aa138d7af7426b42657ace9020bea Mon Sep 17 00:00:00 2001
From: Paul Cuzner <pcuzner@redhat.com>
Date: Mon, 30 May 2022 13:54:33 +1200
Subject: [PATCH] mgr/cephadm: Add new host rescan command

Adds a host rescan command to invoke cephadm's
rescan-disks subcommand

Signed-off-by: Paul Cuzner <pcuzner@redhat.com>
---
 src/pybind/mgr/cephadm/module.py          | 28 +++++++++++++++++++++++
 src/pybind/mgr/orchestrator/_interface.py | 11 +++++++++
 src/pybind/mgr/orchestrator/module.py     | 10 ++++++++
 3 files changed, 49 insertions(+)

diff --git a/src/pybind/mgr/cephadm/module.py b/src/pybind/mgr/cephadm/module.py
index ada900a7f5ac8..2c65df00c38b8 100644
--- a/src/pybind/mgr/cephadm/module.py
+++ b/src/pybind/mgr/cephadm/module.py
@@ -1795,6 +1795,34 @@ Then run the following:
 
         return f"Ceph cluster {self._cluster_fsid} on {hostname} has exited maintenance mode"
 
+    @handle_orch_error
+    @host_exists()
+    def rescan_host(self, hostname: str) -> str:
+        """Use cephadm to issue a disk rescan on each HBA
+
+        Some HBAs and external enclosures don't automatically register
+        device insertion with the kernel, so for these scenarios we need
+        to manually rescan
+
+        :param hostname: (str) host name
+        """
+        self.log.info(f'disk rescan request sent to host "{hostname}"')
+        _out, _err, _code = self.wait_async(CephadmServe(self)._run_cephadm(hostname, cephadmNoImage, "disk-rescan",
+                                                                            [],
+                                                                            no_fsid=True,
+                                                                            error_ok=True))
+        if not _err:
+            raise OrchestratorError('Unexpected response from cephadm disk-rescan call')
+
+        msg = _err[0].split('\n')[-1]
+        log_msg = f'disk rescan: {msg}'
+        if msg.upper().startswith('OK'):
+            self.log.info(log_msg)
+        else:
+            self.log.warning(log_msg)
+
+        return f'{msg}'
+
     def get_minimal_ceph_conf(self) -> str:
         _, config, _ = self.check_mon_command({
             "prefix": "config generate-minimal-conf",
diff --git a/src/pybind/mgr/orchestrator/_interface.py b/src/pybind/mgr/orchestrator/_interface.py
index 294fe8176e1e9..90be46dec5f36 100644
--- a/src/pybind/mgr/orchestrator/_interface.py
+++ b/src/pybind/mgr/orchestrator/_interface.py
@@ -418,6 +418,17 @@ class Orchestrator(object):
         """
         raise NotImplementedError()
 
+    def rescan_host(self, hostname: str) -> OrchResult:
+        """Use cephadm to issue a disk rescan on each HBA
+
+        Some HBAs and external enclosures don't automatically register
+        device insertion with the kernel, so for these scenarios we need
+        to manually rescan
+
+        :param hostname: (str) host name
+        """
+        raise NotImplementedError()
+
     def get_inventory(self, host_filter: Optional['InventoryFilter'] = None, refresh: bool = False) -> OrchResult[List['InventoryHost']]:
         """
         Returns something that was created by `ceph-volume inventory`.
diff --git a/src/pybind/mgr/orchestrator/module.py b/src/pybind/mgr/orchestrator/module.py
index edaa3f99f6db5..81141c4a14bc5 100644
--- a/src/pybind/mgr/orchestrator/module.py
+++ b/src/pybind/mgr/orchestrator/module.py
@@ -457,6 +457,16 @@ class OrchestratorCli(OrchestratorClientMixin, MgrModule,
 
         return HandleCommandResult(stdout=completion.result_str())
 
+    @_cli_write_command('orch host rescan')
+    def _host_rescan(self, hostname: str, with_summary: bool = False) -> HandleCommandResult:
+        """Perform a disk rescan on a host"""
+        completion = self.rescan_host(hostname)
+        raise_if_exception(completion)
+
+        if with_summary:
+            return HandleCommandResult(stdout=completion.result_str())
+        return HandleCommandResult(stdout=completion.result_str().split('.')[0])
+
     @_cli_read_command('orch device ls')
     def _list_devices(self,
                       hostname: Optional[List[str]] = None,
-- 
2.39.5