[pbs-devel] [PATCH proxmox-backup 6/7] Revert "backup: ensure base snapshots are still available after backup"

[Stefan Reiter <s.reiter@proxmox.com>]

This reverts commit d53fbe24741ed3bd920ee1c61bc163b1874b7c82.

The HashSet and "register" function are unnecessary, as we already know
which backup is the one we need to check: the last one, stored as
'last_backup'.

Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
---

The next patch restores this functionality in a much simpler way.

 src/api2/backup.rs             |  1 -
 src/api2/backup/environment.rs | 21 +--------------------
 src/backup/backup_info.rs      |  2 +-
 3 files changed, 2 insertions(+), 22 deletions(-)

diff --git a/src/api2/backup.rs b/src/api2/backup.rs
index 29b1a606..4b751e3e 100644
--- a/src/api2/backup.rs
+++ b/src/api2/backup.rs
@@ -661,7 +661,6 @@ fn download_previous(
             };
             if let Some(index) = index {
                 env.log(format!("register chunks in '{}' from previous backup.", archive_name));
-                env.register_base_snapshot(last_backup.backup_dir.clone());
 
                 for pos in 0..index.index_count() {
                     let info = index.chunk_info(pos).unwrap();
diff --git a/src/api2/backup/environment.rs b/src/api2/backup/environment.rs
index bc780d20..aa039cd9 100644
--- a/src/api2/backup/environment.rs
+++ b/src/api2/backup/environment.rs
@@ -1,6 +1,6 @@
 use anyhow::{bail, format_err, Error};
 use std::sync::{Arc, Mutex};
-use std::collections::{HashMap, HashSet};
+use std::collections::HashMap;
 
 use ::serde::{Serialize};
 use serde_json::{json, Value};
@@ -72,7 +72,6 @@ struct SharedBackupState {
     dynamic_writers: HashMap<usize, DynamicWriterState>,
     fixed_writers: HashMap<usize, FixedWriterState>,
     known_chunks: HashMap<[u8;32], u32>,
-    base_snapshots: HashSet<BackupDir>,
     backup_size: u64, // sums up size of all files
     backup_stat: UploadStatistic,
 }
@@ -126,7 +125,6 @@ impl BackupEnvironment {
             dynamic_writers: HashMap::new(),
             fixed_writers: HashMap::new(),
             known_chunks: HashMap::new(),
-            base_snapshots: HashSet::new(),
             backup_size: 0,
             backup_stat: UploadStatistic::new(),
         };
@@ -145,13 +143,6 @@ impl BackupEnvironment {
         }
     }
 
-    /// Register a snapshot as a predecessor of the current backup.
-    /// It's existance will be ensured on finishing.
-    pub fn register_base_snapshot(&self, snap: BackupDir) {
-        let mut state = self.state.lock().unwrap();
-        state.base_snapshots.insert(snap);
-    }
-
     /// Register a Chunk with associated length.
     ///
     /// We do not fully trust clients, so a client may only use registered
@@ -488,16 +479,6 @@ impl BackupEnvironment {
         self.datastore.store_manifest(&self.backup_dir, manifest)
             .map_err(|err| format_err!("unable to store manifest blob - {}", err))?;
 
-        for snap in &state.base_snapshots {
-            let path = self.datastore.snapshot_path(snap);
-            if !path.exists() {
-                bail!(
-                    "base snapshot {} was removed during backup, cannot finish as chunks might be missing",
-                    snap
-                );
-            }
-        }
-
         // marks the backup as successful
         state.finished = true;
 
diff --git a/src/backup/backup_info.rs b/src/backup/backup_info.rs
index c35928ce..5bd8b8d5 100644
--- a/src/backup/backup_info.rs
+++ b/src/backup/backup_info.rs
@@ -218,7 +218,7 @@ impl std::str::FromStr for BackupGroup {
 /// Uniquely identify a Backup (relative to data store)
 ///
 /// We also call this a backup snaphost.
-#[derive(Debug, Eq, PartialEq, Hash, Clone)]
+#[derive(Debug, Eq, PartialEq, Clone)]
 pub struct BackupDir {
     /// Backup group
     group: BackupGroup,
-- 
2.20.1