[pbs-devel] [PATCH proxmox-backup v5 2/5] fix #3935: datastore/api/backup: add lock helpers to backup dir/group
Stefan Sterz
s.sterz at proxmox.com
Wed Aug 24 14:48:26 CEST 2022
to avoid duplicate code, add helpers for locking groups and snapshots
to the BackupGroup and BackupDir traits respectively and refactor
existing code to use them.
Signed-off-by: Stefan Sterz <s.sterz at proxmox.com>
---
pbs-datastore/src/backup_info.rs | 31 ++++++++++---
pbs-datastore/src/datastore.rs | 68 +++++++++-------------------
pbs-datastore/src/snapshot_reader.rs | 8 +---
src/api2/backup/mod.rs | 8 +---
src/api2/reader/mod.rs | 7 +--
src/backup/verify.rs | 7 +--
6 files changed, 52 insertions(+), 77 deletions(-)
diff --git a/pbs-datastore/src/backup_info.rs b/pbs-datastore/src/backup_info.rs
index c3ce7a1d..52d927ed 100644
--- a/pbs-datastore/src/backup_info.rs
+++ b/pbs-datastore/src/backup_info.rs
@@ -6,7 +6,9 @@ use std::sync::Arc;
use anyhow::{bail, format_err, Error};
-use proxmox_sys::fs::{lock_dir_noblock, replace_file, CreateOptions};
+use proxmox_sys::fs::{
+ lock_dir_noblock, lock_dir_noblock_shared, replace_file, CreateOptions, DirLockGuard,
+};
use pbs_api_types::{
Authid, BackupNamespace, BackupType, GroupFilter, BACKUP_DATE_REGEX, BACKUP_FILE_REGEX,
@@ -200,9 +202,8 @@ impl BackupGroup {
///
/// Returns true if all snapshots were removed, and false if some were protected
pub fn destroy(&self) -> Result<bool, Error> {
+ let _guard = self.lock()?;
let path = self.full_group_path();
- let _guard =
- proxmox_sys::fs::lock_dir_noblock(&path, "backup group", "possible running backup")?;
log::info!("removing backup group {:?}", path);
let mut removed_all_snaps = true;
@@ -236,6 +237,15 @@ impl BackupGroup {
self.store
.set_owner(&self.ns, self.as_ref(), auth_id, force)
}
+
+ /// Lock a group exclusively
+ pub fn lock(&self) -> Result<DirLockGuard, Error> {
+ lock_dir_noblock(
+ &self.full_group_path(),
+ "backup group",
+ "possible running backup",
+ )
+ }
}
impl AsRef<pbs_api_types::BackupNamespace> for BackupGroup {
@@ -439,15 +449,23 @@ impl BackupDir {
.map_err(|err| format_err!("unable to acquire manifest lock {:?} - {}", &path, err))
}
+ /// Lock this snapshot exclusively
+ pub fn lock(&self) -> Result<DirLockGuard, Error> {
+ lock_dir_noblock(&self.full_path(), "snapshot", "possibly running or in use")
+ }
+
+ /// Acquire a shared lock on this snapshot
+ pub fn lock_shared(&self) -> Result<DirLockGuard, Error> {
+ lock_dir_noblock_shared(&self.full_path(), "snapshot", "possibly running or in use")
+ }
+
/// Destroy the whole snapshot, bails if it's protected
///
/// Setting `force` to true skips locking and thus ignores if the backup is currently in use.
pub fn destroy(&self, force: bool) -> Result<(), Error> {
- let full_path = self.full_path();
-
let (_guard, _manifest_guard);
if !force {
- _guard = lock_dir_noblock(&full_path, "snapshot", "possibly running or in use")?;
+ _guard = self.lock()?;
_manifest_guard = self.lock_manifest()?;
}
@@ -455,6 +473,7 @@ impl BackupDir {
bail!("cannot remove protected snapshot"); // use special error type?
}
+ let full_path = self.full_path();
log::info!("removing backup snapshot {:?}", full_path);
std::fs::remove_dir_all(&full_path).map_err(|err| {
format_err!("removing backup snapshot {:?} failed - {}", full_path, err,)
diff --git a/pbs-datastore/src/datastore.rs b/pbs-datastore/src/datastore.rs
index a539ddc5..52a5f079 100644
--- a/pbs-datastore/src/datastore.rs
+++ b/pbs-datastore/src/datastore.rs
@@ -11,8 +11,8 @@ use nix::unistd::{unlinkat, UnlinkatFlags};
use proxmox_schema::ApiType;
+use proxmox_sys::fs::DirLockGuard;
use proxmox_sys::fs::{file_read_optional_string, replace_file, CreateOptions};
-use proxmox_sys::fs::{lock_dir_noblock, DirLockGuard};
use proxmox_sys::process_locker::ProcessLockSharedGuard;
use proxmox_sys::WorkerTaskContext;
use proxmox_sys::{task_log, task_warn};
@@ -630,41 +630,31 @@ impl DataStore {
///
/// This also acquires an exclusive lock on the directory and returns the lock guard.
pub fn create_locked_backup_group(
- &self,
+ self: &Arc<Self>,
ns: &BackupNamespace,
backup_group: &pbs_api_types::BackupGroup,
auth_id: &Authid,
) -> Result<(Authid, DirLockGuard), Error> {
- // create intermediate path first:
- let mut full_path = self.base_path();
- for ns in ns.components() {
- full_path.push("ns");
- full_path.push(ns);
- }
- full_path.push(backup_group.ty.as_str());
- std::fs::create_dir_all(&full_path)?;
+ let backup_group = self.backup_group(ns.clone(), backup_group.clone());
- full_path.push(&backup_group.id);
+ // create intermediate path first
+ let full_path = backup_group.full_group_path();
- // create the last component now
+ std::fs::create_dir_all(&full_path.parent().ok_or(format_err!(
+ "could not construct parent path for group {backup_group:?}"
+ ))?)?;
+
+ // now create the group, this allows us to check whether it existed before
match std::fs::create_dir(&full_path) {
Ok(_) => {
- let guard = lock_dir_noblock(
- &full_path,
- "backup group",
- "another backup is already running",
- )?;
- self.set_owner(ns, backup_group, auth_id, false)?;
- let owner = self.get_owner(ns, backup_group)?; // just to be sure
+ let guard = backup_group.lock()?;
+ self.set_owner(ns, backup_group.group(), auth_id, false)?;
+ let owner = self.get_owner(ns, backup_group.group())?; // just to be sure
Ok((owner, guard))
}
Err(ref err) if err.kind() == io::ErrorKind::AlreadyExists => {
- let guard = lock_dir_noblock(
- &full_path,
- "backup group",
- "another backup is already running",
- )?;
- let owner = self.get_owner(ns, backup_group)?; // just to be sure
+ let guard = backup_group.lock()?;
+ let owner = self.get_owner(ns, backup_group.group())?; // just to be sure
Ok((owner, guard))
}
Err(err) => bail!("unable to create backup group {:?} - {}", full_path, err),
@@ -675,29 +665,17 @@ impl DataStore {
///
/// The BackupGroup directory needs to exist.
pub fn create_locked_backup_dir(
- &self,
+ self: &Arc<Self>,
ns: &BackupNamespace,
backup_dir: &pbs_api_types::BackupDir,
) -> Result<(PathBuf, bool, DirLockGuard), Error> {
- let full_path = self.snapshot_path(ns, backup_dir);
- let relative_path = full_path.strip_prefix(self.base_path()).map_err(|err| {
- format_err!(
- "failed to produce correct path for backup {backup_dir} in namespace {ns}: {err}"
- )
- })?;
-
- let lock = || {
- lock_dir_noblock(
- &full_path,
- "snapshot",
- "internal error - tried creating snapshot that's already in use",
- )
- };
+ let backup_dir = self.backup_dir(ns.clone(), backup_dir.clone())?;
+ let relative_path = backup_dir.relative_path();
- match std::fs::create_dir(&full_path) {
- Ok(_) => Ok((relative_path.to_owned(), true, lock()?)),
+ match std::fs::create_dir(&backup_dir.full_path()) {
+ Ok(_) => Ok((relative_path, true, backup_dir.lock()?)),
Err(ref e) if e.kind() == io::ErrorKind::AlreadyExists => {
- Ok((relative_path.to_owned(), false, lock()?))
+ Ok((relative_path, false, backup_dir.lock()?))
}
Err(e) => Err(e.into()),
}
@@ -1155,9 +1133,7 @@ impl DataStore {
/// Updates the protection status of the specified snapshot.
pub fn update_protection(&self, backup_dir: &BackupDir, protection: bool) -> Result<(), Error> {
- let full_path = backup_dir.full_path();
-
- let _guard = lock_dir_noblock(&full_path, "snapshot", "possibly running or in use")?;
+ let _guard = backup_dir.lock()?;
let protected_path = backup_dir.protected_file();
if protection {
diff --git a/pbs-datastore/src/snapshot_reader.rs b/pbs-datastore/src/snapshot_reader.rs
index 899c3bce..08b2b66e 100644
--- a/pbs-datastore/src/snapshot_reader.rs
+++ b/pbs-datastore/src/snapshot_reader.rs
@@ -6,8 +6,6 @@ use std::sync::Arc;
use anyhow::{bail, Error};
use nix::dir::Dir;
-use proxmox_sys::fs::lock_dir_noblock_shared;
-
use pbs_api_types::{print_store_and_ns, BackupNamespace, Operation};
use crate::backup_info::BackupDir;
@@ -39,10 +37,8 @@ impl SnapshotReader {
pub(crate) fn new_do(snapshot: BackupDir) -> Result<Self, Error> {
let datastore = snapshot.datastore();
- let snapshot_path = snapshot.full_path();
- let locked_dir =
- lock_dir_noblock_shared(&snapshot_path, "snapshot", "locked by another operation")?;
+ let locked_dir = snapshot.lock_shared()?;
let datastore_name = datastore.name().to_string();
let manifest = match snapshot.load_manifest() {
@@ -57,7 +53,7 @@ impl SnapshotReader {
}
};
- let mut client_log_path = snapshot_path;
+ let mut client_log_path = snapshot.full_path();
client_log_path.push(CLIENT_LOG_BLOB_NAME);
let mut file_list = vec![MANIFEST_BLOB_NAME.to_string()];
diff --git a/src/api2/backup/mod.rs b/src/api2/backup/mod.rs
index e519a200..077d70f9 100644
--- a/src/api2/backup/mod.rs
+++ b/src/api2/backup/mod.rs
@@ -27,7 +27,6 @@ use pbs_datastore::manifest::{archive_type, ArchiveType};
use pbs_datastore::{DataStore, PROXMOX_BACKUP_PROTOCOL_ID_V1};
use pbs_tools::json::{required_array_param, required_integer_param, required_string_param};
use proxmox_rest_server::{H2Service, WorkerTask};
-use proxmox_sys::fs::lock_dir_noblock_shared;
mod environment;
use environment::*;
@@ -181,12 +180,7 @@ fn upgrade_to_backup_protocol(
}
// lock last snapshot to prevent forgetting/pruning it during backup
- let full_path = last.backup_dir.full_path();
- Some(lock_dir_noblock_shared(
- &full_path,
- "snapshot",
- "base snapshot is already locked by another operation",
- )?)
+ Some(last.backup_dir.lock_shared()?)
} else {
None
};
diff --git a/src/api2/reader/mod.rs b/src/api2/reader/mod.rs
index e2a10da3..ea7c4aa7 100644
--- a/src/api2/reader/mod.rs
+++ b/src/api2/reader/mod.rs
@@ -27,7 +27,6 @@ use pbs_datastore::manifest::{archive_type, ArchiveType};
use pbs_datastore::{DataStore, PROXMOX_BACKUP_READER_PROTOCOL_ID_V1};
use pbs_tools::json::required_string_param;
use proxmox_rest_server::{H2Service, WorkerTask};
-use proxmox_sys::fs::lock_dir_noblock_shared;
use crate::api2::backup::optional_ns_param;
use crate::api2::helpers;
@@ -125,11 +124,7 @@ fn upgrade_to_backup_reader_protocol(
}
}
- let _guard = lock_dir_noblock_shared(
- &backup_dir.full_path(),
- "snapshot",
- "locked by another operation",
- )?;
+ let _guard = backup_dir.lock_shared()?;
let path = datastore.base_path();
diff --git a/src/backup/verify.rs b/src/backup/verify.rs
index 3984e28d..6c4acf3a 100644
--- a/src/backup/verify.rs
+++ b/src/backup/verify.rs
@@ -16,7 +16,6 @@ use pbs_datastore::backup_info::{BackupDir, BackupGroup, BackupInfo};
use pbs_datastore::index::IndexFile;
use pbs_datastore::manifest::{archive_type, ArchiveType, BackupManifest, FileInfo};
use pbs_datastore::{DataBlob, DataStore, StoreProgress};
-use proxmox_sys::fs::lock_dir_noblock_shared;
use crate::tools::parallel_handler::ParallelHandler;
@@ -328,11 +327,7 @@ pub fn verify_backup_dir(
upid: UPID,
filter: Option<&dyn Fn(&BackupManifest) -> bool>,
) -> Result<bool, Error> {
- let snap_lock = lock_dir_noblock_shared(
- &backup_dir.full_path(),
- "snapshot",
- "locked by another operation",
- );
+ let snap_lock = backup_dir.lock_shared();
match snap_lock {
Ok(snap_lock) => {
verify_backup_dir_with_lock(verify_worker, backup_dir, upid, filter, snap_lock)
--
2.30.2
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