feat(nexus): separate pool configuration from other mayastor configur…

…ation

- create new PoolConfig struct to represent pool configuration,
  and remove pool information from existing Config struct
  (resolves CAS-861)

- add new option to specify yaml file to persist pool configuration
  (resolves CAS-862)

- nexus pool configuration is updated (only) when a pool is created or destroyed,
  (resolves CAS-864)

- at startup, attempt to create pools specified in pool configuration YAML

- remove unused information from main nexus configuration

- remove child status configuration and all references to it

chart/templates/mayastor-daemonset.yaml

@@ -53,6 +53,7 @@ spec:
         - "-g$(MY_POD_IP)"
         - "-nnats"
         - "-y/var/local/mayastor/config.yaml"
+        - "-P/var/local/mayastor/pools.yaml"
         - "-l{{ include "mayastorCpuSpec" . }}"
         - "-pmayastor-etcd"
         securityContext:

deploy/mayastor-daemonset.yaml

@@ -55,6 +55,7 @@ spec:
         - "-g$(MY_POD_IP)"
         - "-nnats"
         - "-y/var/local/mayastor/config.yaml"
+        - "-P/var/local/mayastor/pools.yaml"
         - "-l0"
         - "-pmayastor-etcd"
         securityContext:

mayastor/src/bdev/mod.rs

@@ -12,7 +12,6 @@ pub use nexus::{
         VerboseError,
     },
     nexus_child::{lookup_nexus_child, ChildState, Reason},
-    nexus_child_status_config,
     nexus_label::{GptEntry, GptGuid as Guid, GptHeader},
     nexus_metadata::{
         MetaDataChildEntry,

mayastor/src/bdev/nexus/mod.rs

@@ -26,7 +26,6 @@ pub mod nexus_bdev_rebuild;
 pub mod nexus_bdev_snapshot;
 mod nexus_channel;
 pub(crate) mod nexus_child;
-pub mod nexus_child_status_config;
 mod nexus_config;
 pub mod nexus_fn_table;
 pub mod nexus_io;

mayastor/src/bdev/nexus/nexus_bdev.rs

@@ -687,8 +687,6 @@ impl Nexus {
         }
 
         if r.await.unwrap() {
-            // Update the child states to remove them from the config file.
-            NexusChild::save_state_change();
             Ok(())
         } else {
             Err(Error::NexusDestroy {

mayastor/src/bdev/nexus/nexus_bdev_children.rs

@@ -45,7 +45,6 @@ use crate::{
             },
             nexus_channel::DrEvent,
             nexus_child::{ChildState, NexusChild},
-            nexus_child_status_config::ChildStatusConfig,
         },
         Reason,
         VerboseError,
@@ -196,9 +195,6 @@ impl Nexus {
                 // it can never take part in the IO path
                 // of the nexus until it's rebuilt from a healthy child.
                 child.fault(Reason::OutOfSync).await;
-                if ChildStatusConfig::add(&child).is_err() {
-                    error!("Failed to add child status information");
-                }
 
                 // Register event listener for newly added child.
                 self.register_child_event_listener(&child);
@@ -275,9 +271,6 @@ impl Nexus {
         self.children.remove(idx);
         self.child_count -= 1;
 
-        // Update child status to remove this child
-        NexusChild::save_state_change();
-
         self.start_rebuild_jobs(cancelled_rebuilding_children).await;
         Ok(())
     }
@@ -349,7 +342,6 @@ impl Nexus {
                         ChildState::Faulted(_) => {}
                         _ => {
                             child.fault(reason).await;
-                            NexusChild::save_state_change();
                             self.reconfigure(DrEvent::ChildFault).await;
                         }
                     }

mayastor/src/bdev/nexus/nexus_bdev_rebuild.rs

@@ -20,7 +20,7 @@ use crate::{
                 RemoveRebuildJob,
             },
             nexus_channel::DrEvent,
-            nexus_child::{ChildState, NexusChild, Reason},
+            nexus_child::{ChildState, Reason},
         },
         VerboseError,
     },
@@ -261,7 +261,6 @@ impl Nexus {
         match job.state() {
             RebuildState::Completed => {
                 recovering_child.set_state(ChildState::Open);
-                NexusChild::save_state_change();
                 info!(
                     "Child {} has been rebuilt successfully",
                     recovering_child.get_name()

mayastor/src/bdev/nexus/nexus_channel.rs

@@ -78,8 +78,6 @@ pub enum DrEvent {
     ChildRemove,
     /// Child rebuild event
     ChildRebuild,
-    /// Child status information is being applied
-    ChildStatusSync,
 }
 
 impl NexusChannelInner {
@@ -297,8 +295,7 @@ impl NexusChannel {
             DrEvent::ChildOffline
             | DrEvent::ChildRemove
             | DrEvent::ChildFault
-            | DrEvent::ChildRebuild
-            | DrEvent::ChildStatusSync => unsafe {
+            | DrEvent::ChildRebuild => unsafe {
                 spdk_for_each_channel(
                     device,
                     Some(NexusChannel::refresh_io_channels),

mayastor/src/bdev/nexus/nexus_child.rs

@@ -15,7 +15,6 @@ use crate::{
             instances,
             nexus_channel::DrEvent,
             nexus_child::ChildState::Faulted,
-            nexus_child_status_config::ChildStatusConfig,
         },
         nexus_lookup,
         Guid,
@@ -313,7 +312,6 @@ impl NexusChild {
                 self.set_state(ChildState::Faulted(reason));
             }
         }
-        NexusChild::save_state_change();
     }
 
     /// Set the child as temporarily offline
@@ -326,7 +324,6 @@ impl NexusChild {
                 e.verbose()
             );
         }
-        NexusChild::save_state_change();
     }
 
     /// Get full name of this Nexus child.
@@ -371,17 +368,9 @@ impl NexusChild {
 
         let result = self.open(parent_size);
         self.set_state(ChildState::Faulted(Reason::OutOfSync));
-        NexusChild::save_state_change();
         result
     }
 
-    /// Save the state of the children to the config file
-    pub(crate) fn save_state_change() {
-        if ChildStatusConfig::save().is_err() {
-            error!("Failed to save child status information");
-        }
-    }
-
     /// Extract a UUID from a URI.
     pub(crate) fn uuid(uri: &str) -> Option<String> {
         let url = Url::parse(uri).expect("Failed to parse URI");

mayastor/src/bin/casperf.rs

@@ -323,7 +323,6 @@ fn main() {
         let mut cfg = Config::default();
         cfg.nexus_opts.iscsi_enable = false;
         cfg.nexus_opts.nvmf_enable = false;
-        cfg.sync_disable = true;
         cfg
     });