src/backup/datastore.rs

   1 use std::collections::{HashSet, HashMap};
   2 use std::io::{self, Write};
   3 use std::path::{Path, PathBuf};
   4 use std::sync::{Arc, Mutex};
   5 use std::convert::TryFrom;
   6 use std::str::FromStr;
   7 use std::time::Duration;
   8 use std::fs::File;
   9
  10 use anyhow::{bail, format_err, Error};
  11 use lazy_static::lazy_static;
  12
  13 use proxmox::tools::fs::{replace_file, file_read_optional_string, CreateOptions, open_file_locked};
  14
  15 use super::backup_info::{BackupGroup, BackupDir};
  16 use super::chunk_store::ChunkStore;
  17 use super::dynamic_index::{DynamicIndexReader, DynamicIndexWriter};
  18 use super::fixed_index::{FixedIndexReader, FixedIndexWriter};
  19 use super::manifest::{MANIFEST_BLOB_NAME, MANIFEST_LOCK_NAME, CLIENT_LOG_BLOB_NAME, BackupManifest};
  20 use super::index::*;
  21 use super::{DataBlob, ArchiveType, archive_type};
  22 use crate::config::datastore::{self, DataStoreConfig};
  23 use crate::task::TaskState;
  24 use crate::tools;
  25 use crate::tools::format::HumanByte;
  26 use crate::tools::fs::{lock_dir_noblock, DirLockGuard};
  27 use crate::api2::types::{Authid, GarbageCollectionStatus};
  28 use crate::server::UPID;
  29
  30 lazy_static! {
  31     static ref DATASTORE_MAP: Mutex<HashMap<String, Arc<DataStore>>> = Mutex::new(HashMap::new());
  32 }
  33
  34 /// Datastore Management
  35 ///
  36 /// A Datastore can store severals backups, and provides the
  37 /// management interface for backup.
  38 pub struct DataStore {
  39     chunk_store: Arc<ChunkStore>,
  40     gc_mutex: Mutex<bool>,
  41     last_gc_status: Mutex<GarbageCollectionStatus>,
  42     verify_new: bool,
  43 }
  44
  45 impl DataStore {
  46
  47     pub fn lookup_datastore(name: &str) -> Result<Arc<DataStore>, Error> {
  48
  49         let (config, _digest) = datastore::config()?;
  50         let config: datastore::DataStoreConfig = config.lookup("datastore", name)?;
  51         let path = PathBuf::from(&config.path);
  52
  53         let mut map = DATASTORE_MAP.lock().unwrap();
  54
  55         if let Some(datastore) = map.get(name) {
  56             // Compare Config - if changed, create new Datastore object!
  57             if datastore.chunk_store.base == path &&
  58                 datastore.verify_new == config.verify_new.unwrap_or(false)
  59             {
  60                 return Ok(datastore.clone());
  61             }
  62         }
  63
  64         let datastore = DataStore::open_with_path(name, &path, config)?;
  65
  66         let datastore = Arc::new(datastore);
  67         map.insert(name.to_string(), datastore.clone());
  68
  69         Ok(datastore)
  70     }
  71
  72     fn open_with_path(store_name: &str, path: &Path, config: DataStoreConfig) -> Result<Self, Error> {
  73         let chunk_store = ChunkStore::open(store_name, path)?;
  74
  75         let mut gc_status_path = chunk_store.base_path();
  76         gc_status_path.push(".gc-status");
  77
  78         let gc_status = if let Some(state) = file_read_optional_string(gc_status_path)? {
  79             match serde_json::from_str(&state) {
  80                 Ok(state) => state,
  81                 Err(err) => {
  82                     eprintln!("error reading gc-status: {}", err);
  83                     GarbageCollectionStatus::default()
  84                 }
  85             }
  86         } else {
  87             GarbageCollectionStatus::default()
  88         };
  89
  90         Ok(Self {
  91             chunk_store: Arc::new(chunk_store),
  92             gc_mutex: Mutex::new(false),
  93             last_gc_status: Mutex::new(gc_status),
  94             verify_new: config.verify_new.unwrap_or(false),
  95         })
  96     }
  97
  98     pub fn get_chunk_iterator(
  99         &self,
 100     ) -> Result<
 101         impl Iterator<Item = (Result<tools::fs::ReadDirEntry, Error>, usize, bool)>,
 102         Error
 103     > {
 104         self.chunk_store.get_chunk_iterator()
 105     }
 106
 107     pub fn create_fixed_writer<P: AsRef<Path>>(&self, filename: P, size: usize, chunk_size: usize) -> Result<FixedIndexWriter, Error> {
 108
 109         let index = FixedIndexWriter::create(self.chunk_store.clone(), filename.as_ref(), size, chunk_size)?;
 110
 111         Ok(index)
 112     }
 113
 114     pub fn open_fixed_reader<P: AsRef<Path>>(&self, filename: P) -> Result<FixedIndexReader, Error> {
 115
 116         let full_path =  self.chunk_store.relative_path(filename.as_ref());
 117
 118         let index = FixedIndexReader::open(&full_path)?;
 119
 120         Ok(index)
 121     }
 122
 123     pub fn create_dynamic_writer<P: AsRef<Path>>(
 124         &self, filename: P,
 125     ) -> Result<DynamicIndexWriter, Error> {
 126
 127         let index = DynamicIndexWriter::create(
 128             self.chunk_store.clone(), filename.as_ref())?;
 129
 130         Ok(index)
 131     }
 132
 133     pub fn open_dynamic_reader<P: AsRef<Path>>(&self, filename: P) -> Result<DynamicIndexReader, Error> {
 134
 135         let full_path =  self.chunk_store.relative_path(filename.as_ref());
 136
 137         let index = DynamicIndexReader::open(&full_path)?;
 138
 139         Ok(index)
 140     }
 141
 142     pub fn open_index<P>(&self, filename: P) -> Result<Box<dyn IndexFile + Send>, Error>
 143     where
 144         P: AsRef<Path>,
 145     {
 146         let filename = filename.as_ref();
 147         let out: Box<dyn IndexFile + Send> =
 148             match archive_type(filename)? {
 149                 ArchiveType::DynamicIndex => Box::new(self.open_dynamic_reader(filename)?),
 150                 ArchiveType::FixedIndex => Box::new(self.open_fixed_reader(filename)?),
 151                 _ => bail!("cannot open index file of unknown type: {:?}", filename),
 152             };
 153         Ok(out)
 154     }
 155
 156     pub fn name(&self) -> &str {
 157         self.chunk_store.name()
 158     }
 159
 160     pub fn base_path(&self) -> PathBuf {
 161         self.chunk_store.base_path()
 162     }
 163
 164     /// Cleanup a backup directory
 165     ///
 166     /// Removes all files not mentioned in the manifest.
 167     pub fn cleanup_backup_dir(&self, backup_dir: &BackupDir, manifest: &BackupManifest
 168     ) ->  Result<(), Error> {
 169
 170         let mut full_path = self.base_path();
 171         full_path.push(backup_dir.relative_path());
 172
 173         let mut wanted_files = HashSet::new();
 174         wanted_files.insert(MANIFEST_BLOB_NAME.to_string());
 175         wanted_files.insert(CLIENT_LOG_BLOB_NAME.to_string());
 176         manifest.files().iter().for_each(|item| { wanted_files.insert(item.filename.clone()); });
 177
 178         for item in tools::fs::read_subdir(libc::AT_FDCWD, &full_path)? {
 179             if let Ok(item) = item {
 180                 if let Some(file_type) = item.file_type() {
 181                     if file_type != nix::dir::Type::File { continue; }
 182                 }
 183                 let file_name = item.file_name().to_bytes();
 184                 if file_name == b"." || file_name == b".." { continue; };
 185
 186                 if let Ok(name) = std::str::from_utf8(file_name) {
 187                     if wanted_files.contains(name) { continue; }
 188                 }
 189                 println!("remove unused file {:?}", item.file_name());
 190                 let dirfd = item.parent_fd();
 191                 let _res = unsafe { libc::unlinkat(dirfd, item.file_name().as_ptr(), 0) };
 192             }
 193         }
 194
 195         Ok(())
 196     }
 197
 198     /// Returns the absolute path for a backup_group
 199     pub fn group_path(&self, backup_group: &BackupGroup) -> PathBuf {
 200         let mut full_path = self.base_path();
 201         full_path.push(backup_group.group_path());
 202         full_path
 203     }
 204
 205     /// Returns the absolute path for backup_dir
 206     pub fn snapshot_path(&self, backup_dir: &BackupDir) -> PathBuf {
 207         let mut full_path = self.base_path();
 208         full_path.push(backup_dir.relative_path());
 209         full_path
 210     }
 211
 212     /// Remove a complete backup group including all snapshots
 213     pub fn remove_backup_group(&self, backup_group: &BackupGroup) ->  Result<(), Error> {
 214
 215         let full_path = self.group_path(backup_group);
 216
 217         let _guard = tools::fs::lock_dir_noblock(&full_path, "backup group", "possible running backup")?;
 218
 219         log::info!("removing backup group {:?}", full_path);
 220
 221         // remove all individual backup dirs first to ensure nothing is using them
 222         for snap in backup_group.list_backups(&self.base_path())? {
 223             self.remove_backup_dir(&snap.backup_dir, false)?;
 224         }
 225
 226         // no snapshots left, we can now safely remove the empty folder
 227         std::fs::remove_dir_all(&full_path)
 228             .map_err(|err| {
 229                 format_err!(
 230                     "removing backup group directory {:?} failed - {}",
 231                     full_path,
 232                     err,
 233                 )
 234             })?;
 235
 236         Ok(())
 237     }
 238
 239     /// Remove a backup directory including all content
 240     pub fn remove_backup_dir(&self, backup_dir: &BackupDir, force: bool) ->  Result<(), Error> {
 241
 242         let full_path = self.snapshot_path(backup_dir);
 243
 244         let (_guard, _manifest_guard);
 245         if !force {
 246             _guard = lock_dir_noblock(&full_path, "snapshot", "possibly running or in use")?;
 247             _manifest_guard = self.lock_manifest(backup_dir);
 248         }
 249
 250         log::info!("removing backup snapshot {:?}", full_path);
 251         std::fs::remove_dir_all(&full_path)
 252             .map_err(|err| {
 253                 format_err!(
 254                     "removing backup snapshot {:?} failed - {}",
 255                     full_path,
 256                     err,
 257                 )
 258             })?;
 259
 260         Ok(())
 261     }
 262
 263     /// Returns the time of the last successful backup
 264     ///
 265     /// Or None if there is no backup in the group (or the group dir does not exist).
 266     pub fn last_successful_backup(&self, backup_group: &BackupGroup) -> Result<Option<i64>, Error> {
 267         let base_path = self.base_path();
 268         let mut group_path = base_path.clone();
 269         group_path.push(backup_group.group_path());
 270
 271         if group_path.exists() {
 272             backup_group.last_successful_backup(&base_path)
 273         } else {
 274             Ok(None)
 275         }
 276     }
 277
 278     /// Returns the backup owner.
 279     ///
 280     /// The backup owner is the entity who first created the backup group.
 281     pub fn get_owner(&self, backup_group: &BackupGroup) -> Result<Authid, Error> {
 282         let mut full_path = self.base_path();
 283         full_path.push(backup_group.group_path());
 284         full_path.push("owner");
 285         let owner = proxmox::tools::fs::file_read_firstline(full_path)?;
 286         Ok(owner.trim_end().parse()?) // remove trailing newline
 287     }
 288
 289     /// Set the backup owner.
 290     pub fn set_owner(
 291         &self,
 292         backup_group: &BackupGroup,
 293         auth_id: &Authid,
 294         force: bool,
 295     ) -> Result<(), Error> {
 296         let mut path = self.base_path();
 297         path.push(backup_group.group_path());
 298         path.push("owner");
 299
 300         let mut open_options = std::fs::OpenOptions::new();
 301         open_options.write(true);
 302         open_options.truncate(true);
 303
 304         if force {
 305             open_options.create(true);
 306         } else {
 307             open_options.create_new(true);
 308         }
 309
 310         let mut file = open_options.open(&path)
 311             .map_err(|err| format_err!("unable to create owner file {:?} - {}", path, err))?;
 312
 313         writeln!(file, "{}", auth_id)
 314             .map_err(|err| format_err!("unable to write owner file  {:?} - {}", path, err))?;
 315
 316         Ok(())
 317     }
 318
 319     /// Create (if it does not already exists) and lock a backup group
 320     ///
 321     /// And set the owner to 'userid'. If the group already exists, it returns the
 322     /// current owner (instead of setting the owner).
 323     ///
 324     /// This also acquires an exclusive lock on the directory and returns the lock guard.
 325     pub fn create_locked_backup_group(
 326         &self,
 327         backup_group: &BackupGroup,
 328         auth_id: &Authid,
 329     ) -> Result<(Authid, DirLockGuard), Error> {
 330         // create intermediate path first:
 331         let base_path = self.base_path();
 332
 333         let mut full_path = base_path.clone();
 334         full_path.push(backup_group.backup_type());
 335         std::fs::create_dir_all(&full_path)?;
 336
 337         full_path.push(backup_group.backup_id());
 338
 339         // create the last component now
 340         match std::fs::create_dir(&full_path) {
 341             Ok(_) => {
 342                 let guard = lock_dir_noblock(&full_path, "backup group", "another backup is already running")?;
 343                 self.set_owner(backup_group, auth_id, false)?;
 344                 let owner = self.get_owner(backup_group)?; // just to be sure
 345                 Ok((owner, guard))
 346             }
 347             Err(ref err) if err.kind() == io::ErrorKind::AlreadyExists => {
 348                 let guard = lock_dir_noblock(&full_path, "backup group", "another backup is already running")?;
 349                 let owner = self.get_owner(backup_group)?; // just to be sure
 350                 Ok((owner, guard))
 351             }
 352             Err(err) => bail!("unable to create backup group {:?} - {}", full_path, err),
 353         }
 354     }
 355
 356     /// Creates a new backup snapshot inside a BackupGroup
 357     ///
 358     /// The BackupGroup directory needs to exist.
 359     pub fn create_locked_backup_dir(&self, backup_dir: &BackupDir)
 360         -> Result<(PathBuf, bool, DirLockGuard), Error>
 361     {
 362         let relative_path = backup_dir.relative_path();
 363         let mut full_path = self.base_path();
 364         full_path.push(&relative_path);
 365
 366         let lock = ||
 367             lock_dir_noblock(&full_path, "snapshot", "internal error - tried creating snapshot that's already in use");
 368
 369         match std::fs::create_dir(&full_path) {
 370             Ok(_) => Ok((relative_path, true, lock()?)),
 371             Err(ref e) if e.kind() == io::ErrorKind::AlreadyExists => Ok((relative_path, false, lock()?)),
 372             Err(e) => Err(e.into())
 373         }
 374     }
 375
 376     pub fn list_images(&self) -> Result<Vec<PathBuf>, Error> {
 377         let base = self.base_path();
 378
 379         let mut list = vec![];
 380
 381         use walkdir::WalkDir;
 382
 383         let walker = WalkDir::new(&base).into_iter();
 384
 385         // make sure we skip .chunks (and other hidden files to keep it simple)
 386         fn is_hidden(entry: &walkdir::DirEntry) -> bool {
 387             entry.file_name()
 388                 .to_str()
 389                 .map(|s| s.starts_with("."))
 390                 .unwrap_or(false)
 391         }
 392         let handle_entry_err = |err: walkdir::Error| {
 393             if let Some(inner) = err.io_error() {
 394                 let path = err.path().unwrap_or(Path::new(""));
 395                 match inner.kind() {
 396                     io::ErrorKind::PermissionDenied => {
 397                         // only allow to skip ext4 fsck directory, avoid GC if, for example,
 398                         // a user got file permissions wrong on datastore rsync to new server
 399                         if err.depth() > 1 || !path.ends_with("lost+found") {
 400                             bail!("cannot continue garbage-collection safely, permission denied on: {}", path.display())
 401                         }
 402                     },
 403                     _ => bail!("unexpected error on datastore traversal: {} - {}", inner, path.display()),
 404                 }
 405             }
 406             Ok(())
 407         };
 408         for entry in walker.filter_entry(|e| !is_hidden(e)) {
 409             let path = match entry {
 410                 Ok(entry) => entry.into_path(),
 411                 Err(err) => {
 412                     handle_entry_err(err)?;
 413                     continue
 414                 },
 415             };
 416             if let Ok(archive_type) = archive_type(&path) {
 417                 if archive_type == ArchiveType::FixedIndex || archive_type == ArchiveType::DynamicIndex {
 418                     list.push(path);
 419                 }
 420             }
 421         }
 422
 423         Ok(list)
 424     }
 425
 426     // mark chunks  used by ``index`` as used
 427     fn index_mark_used_chunks<I: IndexFile>(
 428         &self,
 429         index: I,
 430         file_name: &Path, // only used for error reporting
 431         status: &mut GarbageCollectionStatus,
 432         worker: &dyn TaskState,
 433     ) -> Result<(), Error> {
 434
 435         status.index_file_count += 1;
 436         status.index_data_bytes += index.index_bytes();
 437
 438         for pos in 0..index.index_count() {
 439             worker.check_abort()?;
 440             tools::fail_on_shutdown()?;
 441             let digest = index.index_digest(pos).unwrap();
 442             if let Err(err) = self.chunk_store.touch_chunk(digest) {
 443                 crate::task_warn!(
 444                     worker,
 445                     "warning: unable to access chunk {}, required by {:?} - {}",
 446                     proxmox::tools::digest_to_hex(digest),
 447                     file_name,
 448                     err,
 449                 );
 450
 451                 // touch any corresponding .bad files to keep them around, meaning if a chunk is
 452                 // rewritten correctly they will be removed automatically, as well as if no index
 453                 // file requires the chunk anymore (won't get to this loop then)
 454                 for i in 0..=9 {
 455                     let bad_ext = format!("{}.bad", i);
 456                     let mut bad_path = PathBuf::new();
 457                     bad_path.push(self.chunk_path(digest).0);
 458                     bad_path.set_extension(bad_ext);
 459                     self.chunk_store.cond_touch_path(&bad_path, false)?;
 460                 }
 461             }
 462         }
 463         Ok(())
 464     }
 465
 466     fn mark_used_chunks(
 467         &self,
 468         status: &mut GarbageCollectionStatus,
 469         worker: &dyn TaskState,
 470     ) -> Result<(), Error> {
 471
 472         let image_list = self.list_images()?;
 473         let image_count = image_list.len();
 474
 475         let mut done = 0;
 476         let mut last_percentage: usize = 0;
 477
 478         let mut strange_paths_count: u64 = 0;
 479
 480         for img in image_list {
 481
 482             worker.check_abort()?;
 483             tools::fail_on_shutdown()?;
 484
 485             if let Some(backup_dir_path) = img.parent() {
 486                 let backup_dir_path = backup_dir_path.strip_prefix(self.base_path())?;
 487                 if let Some(backup_dir_str) = backup_dir_path.to_str() {
 488                     if BackupDir::from_str(backup_dir_str).is_err() {
 489                         strange_paths_count += 1;
 490                     }
 491                 }
 492             }
 493
 494             match std::fs::File::open(&img) {
 495                 Ok(file) => {
 496                     if let Ok(archive_type) = archive_type(&img) {
 497                         if archive_type == ArchiveType::FixedIndex {
 498                             let index = FixedIndexReader::new(file).map_err(|e| {
 499                                 format_err!("can't read index '{}' - {}", img.to_string_lossy(), e)
 500                             })?;
 501                             self.index_mark_used_chunks(index, &img, status, worker)?;
 502                         } else if archive_type == ArchiveType::DynamicIndex {
 503                             let index = DynamicIndexReader::new(file).map_err(|e| {
 504                                 format_err!("can't read index '{}' - {}", img.to_string_lossy(), e)
 505                             })?;
 506                             self.index_mark_used_chunks(index, &img, status, worker)?;
 507                         }
 508                     }
 509                 }
 510                 Err(err) if err.kind() == io::ErrorKind::NotFound => (), // ignore vanished files
 511                 Err(err) => bail!("can't open index {} - {}", img.to_string_lossy(), err),
 512             }
 513             done += 1;
 514
 515             let percentage = done*100/image_count;
 516             if percentage > last_percentage {
 517                 crate::task_log!(
 518                     worker,
 519                     "marked {}% ({} of {} index files)",
 520                     percentage,
 521                     done,
 522                     image_count,
 523                 );
 524                 last_percentage = percentage;
 525             }
 526         }
 527
 528         if strange_paths_count > 0 {
 529             crate::task_log!(
 530                 worker,
 531                 "found (and marked) {} index files outside of expected directory scheme",
 532                 strange_paths_count,
 533             );
 534         }
 535
 536
 537         Ok(())
 538     }
 539
 540     pub fn last_gc_status(&self) -> GarbageCollectionStatus {
 541         self.last_gc_status.lock().unwrap().clone()
 542     }
 543
 544     pub fn garbage_collection_running(&self) -> bool {
 545         if let Ok(_) = self.gc_mutex.try_lock() { false } else { true }
 546     }
 547
 548     pub fn garbage_collection(&self, worker: &dyn TaskState, upid: &UPID) -> Result<(), Error> {
 549
 550         if let Ok(ref mut _mutex) = self.gc_mutex.try_lock() {
 551
 552             // avoids that we run GC if an old daemon process has still a
 553             // running backup writer, which is not save as we have no "oldest
 554             // writer" information and thus no safe atime cutoff
 555             let _exclusive_lock =  self.chunk_store.try_exclusive_lock()?;
 556
 557             let phase1_start_time = proxmox::tools::time::epoch_i64();
 558             let oldest_writer = self.chunk_store.oldest_writer().unwrap_or(phase1_start_time);
 559
 560             let mut gc_status = GarbageCollectionStatus::default();
 561             gc_status.upid = Some(upid.to_string());
 562
 563             crate::task_log!(worker, "Start GC phase1 (mark used chunks)");
 564
 565             self.mark_used_chunks(&mut gc_status, worker)?;
 566
 567             crate::task_log!(worker, "Start GC phase2 (sweep unused chunks)");
 568             self.chunk_store.sweep_unused_chunks(
 569                 oldest_writer,
 570                 phase1_start_time,
 571                 &mut gc_status,
 572                 worker,
 573             )?;
 574
 575             crate::task_log!(
 576                 worker,
 577                 "Removed garbage: {}",
 578                 HumanByte::from(gc_status.removed_bytes),
 579             );
 580             crate::task_log!(worker, "Removed chunks: {}", gc_status.removed_chunks);
 581             if gc_status.pending_bytes > 0 {
 582                 crate::task_log!(
 583                     worker,
 584                     "Pending removals: {} (in {} chunks)",
 585                     HumanByte::from(gc_status.pending_bytes),
 586                     gc_status.pending_chunks,
 587                 );
 588             }
 589             if gc_status.removed_bad > 0 {
 590                 crate::task_log!(worker, "Removed bad chunks: {}", gc_status.removed_bad);
 591             }
 592
 593             if gc_status.still_bad > 0 {
 594                 crate::task_log!(worker, "Leftover bad chunks: {}", gc_status.still_bad);
 595             }
 596
 597             crate::task_log!(
 598                 worker,
 599                 "Original data usage: {}",
 600                 HumanByte::from(gc_status.index_data_bytes),
 601             );
 602
 603             if gc_status.index_data_bytes > 0 {
 604                 let comp_per = (gc_status.disk_bytes as f64 * 100.)/gc_status.index_data_bytes as f64;
 605                 crate::task_log!(
 606                     worker,
 607                     "On-Disk usage: {} ({:.2}%)",
 608                     HumanByte::from(gc_status.disk_bytes),
 609                     comp_per,
 610                 );
 611             }
 612
 613             crate::task_log!(worker, "On-Disk chunks: {}", gc_status.disk_chunks);
 614
 615             let deduplication_factor = if gc_status.disk_bytes > 0 {
 616                 (gc_status.index_data_bytes as f64)/(gc_status.disk_bytes as f64)
 617             } else {
 618                 1.0
 619             };
 620
 621             crate::task_log!(worker, "Deduplication factor: {:.2}", deduplication_factor);
 622
 623             if gc_status.disk_chunks > 0 {
 624                 let avg_chunk = gc_status.disk_bytes/(gc_status.disk_chunks as u64);
 625                 crate::task_log!(worker, "Average chunk size: {}", HumanByte::from(avg_chunk));
 626             }
 627
 628             if let Ok(serialized) = serde_json::to_string(&gc_status) {
 629                 let mut path = self.base_path();
 630                 path.push(".gc-status");
 631
 632                 let backup_user = crate::backup::backup_user()?;
 633                 let mode = nix::sys::stat::Mode::from_bits_truncate(0o0644);
 634                 // set the correct owner/group/permissions while saving file
 635                 // owner(rw) = backup, group(r)= backup
 636                 let options = CreateOptions::new()
 637                     .perm(mode)
 638                     .owner(backup_user.uid)
 639                     .group(backup_user.gid);
 640
 641                 // ignore errors
 642                 let _ = replace_file(path, serialized.as_bytes(), options);
 643             }
 644
 645             *self.last_gc_status.lock().unwrap() = gc_status;
 646
 647         } else {
 648             bail!("Start GC failed - (already running/locked)");
 649         }
 650
 651         Ok(())
 652     }
 653
 654     pub fn try_shared_chunk_store_lock(&self) -> Result<tools::ProcessLockSharedGuard, Error> {
 655         self.chunk_store.try_shared_lock()
 656     }
 657
 658     pub fn chunk_path(&self, digest:&[u8; 32]) -> (PathBuf, String) {
 659         self.chunk_store.chunk_path(digest)
 660     }
 661
 662     pub fn cond_touch_chunk(&self, digest: &[u8; 32], fail_if_not_exist: bool) -> Result<bool, Error> {
 663         self.chunk_store.cond_touch_chunk(digest, fail_if_not_exist)
 664     }
 665
 666     pub fn insert_chunk(
 667         &self,
 668         chunk: &DataBlob,
 669         digest: &[u8; 32],
 670     ) -> Result<(bool, u64), Error> {
 671         self.chunk_store.insert_chunk(chunk, digest)
 672     }
 673
 674     pub fn load_blob(&self, backup_dir: &BackupDir, filename: &str) -> Result<DataBlob, Error> {
 675         let mut path = self.base_path();
 676         path.push(backup_dir.relative_path());
 677         path.push(filename);
 678
 679         proxmox::try_block!({
 680             let mut file = std::fs::File::open(&path)?;
 681             DataBlob::load_from_reader(&mut file)
 682         }).map_err(|err| format_err!("unable to load blob '{:?}' - {}", path, err))
 683     }
 684
 685
 686     pub fn load_chunk(&self, digest: &[u8; 32]) -> Result<DataBlob, Error> {
 687
 688         let (chunk_path, digest_str) = self.chunk_store.chunk_path(digest);
 689
 690         proxmox::try_block!({
 691             let mut file = std::fs::File::open(&chunk_path)?;
 692             DataBlob::load_from_reader(&mut file)
 693         }).map_err(|err| format_err!(
 694             "store '{}', unable to load chunk '{}' - {}",
 695             self.name(),
 696             digest_str,
 697             err,
 698         ))
 699     }
 700
 701     fn lock_manifest(
 702         &self,
 703         backup_dir: &BackupDir,
 704     ) -> Result<File, Error> {
 705         let mut path = self.base_path();
 706         path.push(backup_dir.relative_path());
 707         path.push(&MANIFEST_LOCK_NAME);
 708
 709         // update_manifest should never take a long time, so if someone else has
 710         // the lock we can simply block a bit and should get it soon
 711         open_file_locked(&path, Duration::from_secs(5), true)
 712             .map_err(|err| {
 713                 format_err!(
 714                     "unable to acquire manifest lock {:?} - {}", &path, err
 715                 )
 716             })
 717     }
 718
 719     /// Load the manifest without a lock. Must not be written back.
 720     pub fn load_manifest(
 721         &self,
 722         backup_dir: &BackupDir,
 723     ) -> Result<(BackupManifest, u64), Error> {
 724         let blob = self.load_blob(backup_dir, MANIFEST_BLOB_NAME)?;
 725         let raw_size = blob.raw_size();
 726         let manifest = BackupManifest::try_from(blob)?;
 727         Ok((manifest, raw_size))
 728     }
 729
 730     /// Update the manifest of the specified snapshot. Never write a manifest directly,
 731     /// only use this method - anything else may break locking guarantees.
 732     pub fn update_manifest(
 733         &self,
 734         backup_dir: &BackupDir,
 735         update_fn: impl FnOnce(&mut BackupManifest),
 736     ) -> Result<(), Error> {
 737
 738         let _guard = self.lock_manifest(backup_dir)?;
 739         let (mut manifest, _) = self.load_manifest(&backup_dir)?;
 740
 741         update_fn(&mut manifest);
 742
 743         let manifest = serde_json::to_value(manifest)?;
 744         let manifest = serde_json::to_string_pretty(&manifest)?;
 745         let blob = DataBlob::encode(manifest.as_bytes(), None, true)?;
 746         let raw_data = blob.raw_data();
 747
 748         let mut path = self.base_path();
 749         path.push(backup_dir.relative_path());
 750         path.push(MANIFEST_BLOB_NAME);
 751
 752         // atomic replace invalidates flock - no other writes past this point!
 753         replace_file(&path, raw_data, CreateOptions::new())?;
 754
 755         Ok(())
 756     }
 757
 758     pub fn verify_new(&self) -> bool {
 759         self.verify_new
 760     }
 761 }