[pbs-devel] [PATCH proxmox-backup v3 3/3] api: assert that maintenance mode transitions are valid

[Dietmar Maurer]

Maintenance mode Delete locks the datastore. It must not be possible to go
back to normal modes, because the datastore may be in undefined state.

Signed-off-by: Dietmar Maurer <dietmar at proxmox.com>
---
 pbs-api-types/src/datastore.rs | 31 +++++++++++++++++++++++++++++++
 pbs-datastore/src/datastore.rs |  8 ++++++--
 src/api2/config/datastore.rs   | 13 ++++++++++---
 3 files changed, 47 insertions(+), 5 deletions(-)

diff --git a/pbs-api-types/src/datastore.rs b/pbs-api-types/src/datastore.rs
index 483cdef4..8a8ec12d 100644
--- a/pbs-api-types/src/datastore.rs
+++ b/pbs-api-types/src/datastore.rs
@@ -344,6 +344,37 @@ impl DataStoreConfig {
             .ok()
         })
     }
+
+    pub fn set_maintenance_mode(&mut self, new_mode: Option<MaintenanceMode>) -> Result<(), Error> {
+        let current_type = self.get_maintenance_mode().map(|mode| mode.ty);
+        let new_type = new_mode.as_ref().map(|mode| mode.ty);
+
+        match current_type {
+            Some(MaintenanceType::ReadOnly) => { /* always OK  */ }
+            Some(MaintenanceType::Offline) => { /* always OK  */ }
+            Some(MaintenanceType::Delete) => {
+                match new_type {
+                    Some(MaintenanceType::Delete) => { /* allow to delete a deleted storage */ }
+                    _ => {
+                        bail!("datastore is being deleted")
+                    }
+                }
+            }
+            None => { /* always OK  */ }
+        }
+
+        let new_mode = match new_mode {
+            Some(new_mode) => Some(
+                proxmox_schema::property_string::PropertyString::new(new_mode)
+                    .to_property_string()?,
+            ),
+            None => None,
+        };
+
+        self.maintenance_mode = new_mode;
+
+        Ok(())
+    }
 }
 
 #[api(
diff --git a/pbs-datastore/src/datastore.rs b/pbs-datastore/src/datastore.rs
index 0685cc84..f95da761 100644
--- a/pbs-datastore/src/datastore.rs
+++ b/pbs-datastore/src/datastore.rs
@@ -20,7 +20,7 @@ use proxmox_sys::{task_log, task_warn};
 
 use pbs_api_types::{
     Authid, BackupNamespace, BackupType, ChunkOrder, DataStoreConfig, DatastoreFSyncLevel,
-    DatastoreTuning, GarbageCollectionStatus, Operation, UPID,
+    DatastoreTuning, GarbageCollectionStatus, MaintenanceMode, MaintenanceType, Operation, UPID,
 };
 
 use crate::backup_info::{BackupDir, BackupGroup, BackupGroupDeleteStats};
@@ -1390,7 +1390,11 @@ impl DataStore {
         let (mut config, _digest) = pbs_config::datastore::config()?;
         let mut datastore_config: DataStoreConfig = config.lookup("datastore", name)?;
 
-        datastore_config.maintenance_mode = Some("type=delete".to_string());
+        datastore_config.set_maintenance_mode(Some(MaintenanceMode {
+            ty: MaintenanceType::Delete,
+            message: None,
+        }))?;
+
         config.set_data(name, "datastore", &datastore_config)?;
         pbs_config::datastore::save_config(&config)?;
         drop(config_lock);
diff --git a/src/api2/config/datastore.rs b/src/api2/config/datastore.rs
index 3081e1f4..87425ff5 100644
--- a/src/api2/config/datastore.rs
+++ b/src/api2/config/datastore.rs
@@ -13,7 +13,7 @@ use proxmox_uuid::Uuid;
 
 use pbs_api_types::{
     Authid, DataStoreConfig, DataStoreConfigUpdater, DatastoreNotify, DatastoreTuning, KeepOptions,
-    PruneJobConfig, PruneJobOptions, DATASTORE_SCHEMA, PRIV_DATASTORE_ALLOCATE,
+    MaintenanceMode, PruneJobConfig, PruneJobOptions, DATASTORE_SCHEMA, PRIV_DATASTORE_ALLOCATE,
     PRIV_DATASTORE_AUDIT, PRIV_DATASTORE_MODIFY, PROXMOX_CONFIG_DIGEST_SCHEMA, UPID_SCHEMA,
 };
 use pbs_config::BackupLockGuard;
@@ -319,7 +319,7 @@ pub fn update_datastore(
                     data.tuning = None;
                 }
                 DeletableProperty::MaintenanceMode => {
-                    data.maintenance_mode = None;
+                    data.set_maintenance_mode(None)?;
                 }
             }
         }
@@ -392,7 +392,14 @@ pub fn update_datastore(
     let mut maintenance_mode_changed = false;
     if update.maintenance_mode.is_some() {
         maintenance_mode_changed = data.maintenance_mode != update.maintenance_mode;
-        data.maintenance_mode = update.maintenance_mode;
+
+        let maintenance_mode = match update.maintenance_mode {
+            Some(mode_str) => Some(MaintenanceMode::deserialize(
+                proxmox_schema::de::SchemaDeserializer::new(mode_str, &MaintenanceMode::API_SCHEMA),
+            )?),
+            None => None,
+        };
+        data.set_maintenance_mode(maintenance_mode)?;
     }
 
     config.set_data(&name, "datastore", &data)?;
-- 
2.39.2