src/tape/pool_writer.rs

   1 use std::collections::HashSet;
   2 use std::path::Path;
   3 use std::time::SystemTime;
   4
   5 use anyhow::{bail, Error};
   6
   7 use proxmox::tools::Uuid;
   8
   9 use crate::{
  10     task_log,
  11     backup::{
  12         DataStore,
  13     },
  14     server::WorkerTask,
  15     tape::{
  16         TAPE_STATUS_DIR,
  17         MAX_CHUNK_ARCHIVE_SIZE,
  18         COMMIT_BLOCK_SIZE,
  19         TapeWrite,
  20         SnapshotReader,
  21         SnapshotChunkIterator,
  22         MediaPool,
  23         MediaId,
  24         MediaCatalog,
  25         MediaSetCatalog,
  26         file_formats::{
  27             MediaSetLabel,
  28             ChunkArchiveWriter,
  29             tape_write_snapshot_archive,
  30         },
  31         drive::{
  32             TapeDriver,
  33             request_and_load_media,
  34             tape_alert_flags_critical,
  35             media_changer,
  36         },
  37     },
  38     config::tape_encryption_keys::load_key_configs,
  39 };
  40
  41
  42 struct PoolWriterState {
  43     drive: Box<dyn TapeDriver>,
  44     catalog: MediaCatalog,
  45     // tell if we already moved to EOM
  46     at_eom: bool,
  47     // bytes written after the last tape fush/sync
  48     bytes_written: usize,
  49 }
  50
  51 impl PoolWriterState {
  52
  53     fn commit(&mut self) -> Result<(), Error> {
  54         self.drive.sync()?; // sync all data to the tape
  55         self.catalog.commit()?; // then commit the catalog
  56         self.bytes_written = 0;
  57         Ok(())
  58     }
  59 }
  60
  61 /// Helper to manage a backup job, writing several tapes of a pool
  62 pub struct PoolWriter {
  63     pool: MediaPool,
  64     drive_name: String,
  65     status: Option<PoolWriterState>,
  66     media_set_catalog: MediaSetCatalog,
  67 }
  68
  69 impl PoolWriter {
  70
  71     pub fn new(mut pool: MediaPool, drive_name: &str) -> Result<Self, Error> {
  72
  73         let current_time = proxmox::tools::time::epoch_i64();
  74
  75         pool.start_write_session(current_time)?;
  76
  77         let mut media_set_catalog = MediaSetCatalog::new();
  78
  79         // load all catalogs read-only at start
  80         for media_uuid in pool.current_media_list()? {
  81             let media_catalog = MediaCatalog::open(
  82                 Path::new(TAPE_STATUS_DIR),
  83                 &media_uuid,
  84                 false,
  85                 false,
  86             )?;
  87             media_set_catalog.append_catalog(media_catalog)?;
  88         }
  89
  90         Ok(Self {
  91             pool,
  92             drive_name: drive_name.to_string(),
  93             status: None,
  94             media_set_catalog,
  95          })
  96     }
  97
  98     pub fn pool(&mut self) -> &mut MediaPool {
  99         &mut self.pool
 100     }
 101
 102     /// Set media status to FULL (persistent - stores pool status)
 103     pub fn set_media_status_full(&mut self, uuid: &Uuid) -> Result<(), Error> {
 104         self.pool.set_media_status_full(&uuid)?;
 105         Ok(())
 106     }
 107
 108     pub fn contains_snapshot(&self, snapshot: &str) -> bool {
 109         if let Some(PoolWriterState { ref catalog, .. }) = self.status {
 110             if catalog.contains_snapshot(snapshot) {
 111                 return true;
 112             }
 113         }
 114         self.media_set_catalog.contains_snapshot(snapshot)
 115     }
 116
 117     /// Eject media and drop PoolWriterState (close drive)
 118     pub fn eject_media(&mut self, worker: &WorkerTask) -> Result<(), Error> {
 119         let mut status = match self.status.take() {
 120             Some(status) => status,
 121             None => return Ok(()), // no media loaded
 122         };
 123
 124         let (drive_config, _digest) = crate::config::drive::config()?;
 125
 126         if let Some((mut changer, _)) = media_changer(&drive_config, &self.drive_name)? {
 127             worker.log("eject media");
 128             status.drive.eject_media()?; // rewind and eject early, so that unload_media is faster
 129             drop(status); // close drive
 130             worker.log("unload media");
 131             changer.unload_media(None)?; //eject and unload
 132         } else {
 133             worker.log("standalone drive - ejecting media");
 134             status.drive.eject_media()?;
 135         }
 136
 137         Ok(())
 138     }
 139
 140     /// Export current media set and drop PoolWriterState (close drive)
 141     pub fn export_media_set(&mut self, worker: &WorkerTask) -> Result<(), Error> {
 142         let mut status = self.status.take();
 143
 144         let (drive_config, _digest) = crate::config::drive::config()?;
 145
 146         if let Some((mut changer, _)) = media_changer(&drive_config, &self.drive_name)? {
 147
 148             if let Some(ref mut status) = status {
 149                 worker.log("eject media");
 150                 status.drive.eject_media()?; // rewind and eject early, so that unload_media is faster
 151             }
 152             drop(status); // close drive
 153
 154             worker.log("unload media");
 155             changer.unload_media(None)?;
 156
 157             for media_uuid in self.pool.current_media_list()? {
 158                 let media = self.pool.lookup_media(media_uuid)?;
 159                 let label_text = media.label_text();
 160                 if let Some(slot) = changer.export_media(label_text)? {
 161                     worker.log(format!("exported media '{}' to import/export slot {}", label_text, slot));
 162                 } else {
 163                     worker.warn(format!("export failed - media '{}' is not online", label_text));
 164                 }
 165             }
 166
 167         } else if let Some(mut status) = status {
 168             worker.log("standalone drive - ejecting media instead of export");
 169             status.drive.eject_media()?;
 170         }
 171
 172         Ok(())
 173     }
 174
 175     /// commit changes to tape and catalog
 176     ///
 177     /// This is done automatically during a backupsession, but needs to
 178     /// be called explicitly before dropping the PoolWriter
 179     pub fn commit(&mut self) -> Result<(), Error> {
 180         if let Some(ref mut status) = self.status {
 181             status.commit()?;
 182         }
 183         Ok(())
 184     }
 185
 186     /// Load a writable media into the drive
 187     pub fn load_writable_media(&mut self, worker: &WorkerTask) -> Result<Uuid, Error> {
 188         let last_media_uuid = match self.status {
 189             Some(PoolWriterState { ref catalog, .. }) => Some(catalog.uuid().clone()),
 190             None => None,
 191         };
 192
 193         let current_time = proxmox::tools::time::epoch_i64();
 194         let media_uuid = self.pool.alloc_writable_media(current_time)?;
 195
 196         let media = self.pool.lookup_media(&media_uuid).unwrap();
 197
 198         let media_changed = match last_media_uuid {
 199             Some(ref last_media_uuid) => last_media_uuid != &media_uuid,
 200             None => true,
 201         };
 202
 203         if !media_changed {
 204             return Ok(media_uuid);
 205         }
 206
 207         task_log!(worker, "allocated new writable media '{}'", media.label_text());
 208
 209         // remove read-only catalog (we store a writable version in status)
 210         self.media_set_catalog.remove_catalog(&media_uuid);
 211
 212         if let Some(PoolWriterState {mut drive, catalog, .. }) = self.status.take() {
 213             self.media_set_catalog.append_catalog(catalog)?;
 214             task_log!(worker, "eject current media");
 215             drive.eject_media()?;
 216         }
 217
 218         let (drive_config, _digest) = crate::config::drive::config()?;
 219
 220         let (mut drive, old_media_id) =
 221             request_and_load_media(worker, &drive_config, &self.drive_name, media.label())?;
 222
 223         // test for critical tape alert flags
 224         if let Ok(alert_flags) = drive.tape_alert_flags() {
 225             if !alert_flags.is_empty() {
 226                 worker.log(format!("TapeAlertFlags: {:?}", alert_flags));
 227                 if tape_alert_flags_critical(alert_flags) {
 228                     bail!("aborting due to critical tape alert flags: {:?}", alert_flags);
 229                 }
 230             }
 231         }
 232
 233         let catalog = update_media_set_label(
 234             worker,
 235             drive.as_mut(),
 236             old_media_id.media_set_label,
 237             media.id(),
 238         )?;
 239
 240         let media_set = media.media_set_label().clone().unwrap();
 241
 242         let encrypt_fingerprint = media_set
 243             .encryption_key_fingerprint
 244             .clone()
 245             .map(|fp| (fp, media_set.uuid.clone()));
 246
 247         drive.set_encryption(encrypt_fingerprint)?;
 248
 249         self.status = Some(PoolWriterState { drive, catalog, at_eom: false, bytes_written: 0 });
 250
 251         Ok(media_uuid)
 252     }
 253
 254     /// uuid of currently loaded BackupMedia
 255     pub fn current_media_uuid(&self) -> Result<&Uuid, Error> {
 256         match self.status {
 257             Some(PoolWriterState { ref catalog, ..}) => Ok(catalog.uuid()),
 258             None => bail!("PoolWriter - no media loaded"),
 259         }
 260     }
 261
 262     /// Move to EOM (if not aleady there), then creates a new snapshot
 263     /// archive writing specified files (as .pxar) into it. On
 264     /// success, this return 'Ok(true)' and the media catalog gets
 265     /// updated.
 266
 267     /// Please note that this may fail when there is not enough space
 268     /// on the media (return value 'Ok(false, _)'). In that case, the
 269     /// archive is marked incomplete, and we do not use it. The caller
 270     /// should mark the media as full and try again using another
 271     /// media.
 272     pub fn append_snapshot_archive(
 273         &mut self,
 274         worker: &WorkerTask,
 275         snapshot_reader: &SnapshotReader,
 276     ) -> Result<(bool, usize), Error> {
 277
 278         let status = match self.status {
 279             Some(ref mut status) => status,
 280             None => bail!("PoolWriter - no media loaded"),
 281         };
 282
 283         if !status.at_eom {
 284             worker.log(String::from("moving to end of media"));
 285             status.drive.move_to_eom()?;
 286             status.at_eom = true;
 287         }
 288
 289         let current_file_number = status.drive.current_file_number()?;
 290         if current_file_number < 2 {
 291             bail!("got strange file position number from drive ({})", current_file_number);
 292         }
 293
 294         let (done, bytes_written) = {
 295             let mut writer: Box<dyn TapeWrite> = status.drive.write_file()?;
 296
 297             match tape_write_snapshot_archive(writer.as_mut(), snapshot_reader)? {
 298                 Some(content_uuid) => {
 299                     status.catalog.register_snapshot(
 300                         content_uuid,
 301                         current_file_number,
 302                         &snapshot_reader.snapshot().to_string(),
 303                     )?;
 304                     (true, writer.bytes_written())
 305                 }
 306                 None => (false, writer.bytes_written()),
 307             }
 308         };
 309
 310         status.bytes_written += bytes_written;
 311
 312         let request_sync = status.bytes_written >= COMMIT_BLOCK_SIZE;
 313
 314         if !done || request_sync {
 315             status.commit()?;
 316         }
 317
 318         Ok((done, bytes_written))
 319     }
 320
 321     /// Move to EOM (if not aleady there), then creates a new chunk
 322     /// archive and writes chunks from 'chunk_iter'. This stops when
 323     /// it detect LEOM or when we reach max archive size
 324     /// (4GB). Written chunks are registered in the media catalog.
 325     pub fn append_chunk_archive(
 326         &mut self,
 327         worker: &WorkerTask,
 328         datastore: &DataStore,
 329         chunk_iter: &mut std::iter::Peekable<SnapshotChunkIterator>,
 330     ) -> Result<(bool, usize), Error> {
 331
 332         let status = match self.status {
 333             Some(ref mut status) => status,
 334             None => bail!("PoolWriter - no media loaded"),
 335         };
 336
 337         if !status.at_eom {
 338             worker.log(String::from("moving to end of media"));
 339             status.drive.move_to_eom()?;
 340             status.at_eom = true;
 341         }
 342
 343         let current_file_number = status.drive.current_file_number()?;
 344         if current_file_number < 2 {
 345             bail!("got strange file position number from drive ({})", current_file_number);
 346         }
 347         let writer = status.drive.write_file()?;
 348
 349         let start_time = SystemTime::now();
 350
 351         let (saved_chunks, content_uuid, leom, bytes_written) = write_chunk_archive(
 352             worker,
 353             writer,
 354             datastore,
 355             chunk_iter,
 356             &self.media_set_catalog,
 357             &status.catalog,
 358             MAX_CHUNK_ARCHIVE_SIZE,
 359         )?;
 360
 361         status.bytes_written += bytes_written;
 362
 363         let elapsed =  start_time.elapsed()?.as_secs_f64();
 364         worker.log(format!(
 365             "wrote {:.2} MB ({} MB/s)",
 366             bytes_written as f64 / (1024.0*1024.0),
 367             (bytes_written as f64)/(1024.0*1024.0*elapsed),
 368         ));
 369
 370         let request_sync = status.bytes_written >= COMMIT_BLOCK_SIZE;
 371
 372         // register chunks in media_catalog
 373         status.catalog.start_chunk_archive(content_uuid, current_file_number)?;
 374         for digest in saved_chunks {
 375             status.catalog.register_chunk(&digest)?;
 376         }
 377         status.catalog.end_chunk_archive()?;
 378
 379         if leom || request_sync {
 380             status.commit()?;
 381         }
 382
 383         Ok((leom, bytes_written))
 384     }
 385 }
 386
 387 /// write up to <max_size> of chunks
 388 fn write_chunk_archive<'a>(
 389     worker: &WorkerTask,
 390     writer: Box<dyn 'a + TapeWrite>,
 391     datastore: &DataStore,
 392     chunk_iter: &mut std::iter::Peekable<SnapshotChunkIterator>,
 393     media_set_catalog: &MediaSetCatalog,
 394     media_catalog: &MediaCatalog,
 395     max_size: usize,
 396 ) -> Result<(Vec<[u8;32]>, Uuid, bool, usize), Error> {
 397
 398     let (mut writer, content_uuid) = ChunkArchiveWriter::new(writer, true)?;
 399
 400     let mut chunk_index: HashSet<[u8;32]> = HashSet::new();
 401
 402     // we want to get the chunk list in correct order
 403     let mut chunk_list: Vec<[u8;32]> = Vec::new();
 404
 405     let mut leom = false;
 406
 407     loop {
 408         let digest = match chunk_iter.next() {
 409             None => break,
 410             Some(digest) => digest?,
 411         };
 412         if media_catalog.contains_chunk(&digest)
 413             || chunk_index.contains(&digest)
 414             || media_set_catalog.contains_chunk(&digest)
 415         {
 416             continue;
 417         }
 418
 419         let blob = datastore.load_chunk(&digest)?;
 420         //println!("CHUNK {} size {}", proxmox::tools::digest_to_hex(&digest), blob.raw_size());
 421
 422         match writer.try_write_chunk(&digest, &blob) {
 423              Ok(true) => {
 424                 chunk_index.insert(digest);
 425                 chunk_list.push(digest);
 426             }
 427             Ok(false) => {
 428                 leom = true;
 429                 break;
 430             }
 431             Err(err) => bail!("write chunk failed - {}", err),
 432         }
 433
 434         if writer.bytes_written() > max_size {
 435             worker.log("Chunk Archive max size reached, closing archive".to_string());
 436             break;
 437         }
 438     }
 439
 440     writer.finish()?;
 441
 442     Ok((chunk_list, content_uuid, leom, writer.bytes_written()))
 443 }
 444
 445 // Compare the media set label. If the media is empty, or the existing
 446 // set label does not match the expected media set, overwrite the
 447 // media set label.
 448 fn update_media_set_label(
 449     worker: &WorkerTask,
 450     drive: &mut dyn TapeDriver,
 451     old_set: Option<MediaSetLabel>,
 452     media_id: &MediaId,
 453 ) -> Result<MediaCatalog, Error> {
 454
 455     let media_catalog;
 456
 457     let new_set = match media_id.media_set_label {
 458         None => bail!("got media without media set - internal error"),
 459         Some(ref set) => set,
 460     };
 461
 462     let key_config = if let Some(ref fingerprint) = new_set.encryption_key_fingerprint {
 463         let (config_map, _digest) = load_key_configs()?;
 464         match config_map.get(fingerprint) {
 465             Some(key_config) => Some(key_config.clone()),
 466             None => {
 467                 bail!("unable to find tape encryption key config '{}'", fingerprint);
 468             }
 469         }
 470     } else {
 471         None
 472     };
 473
 474     let status_path = Path::new(TAPE_STATUS_DIR);
 475
 476     match old_set {
 477         None => {
 478             worker.log("wrinting new media set label".to_string());
 479             drive.write_media_set_label(new_set, key_config.as_ref())?;
 480             media_catalog = MediaCatalog::overwrite(status_path, media_id, false)?;
 481         }
 482         Some(media_set_label) => {
 483             if new_set.uuid == media_set_label.uuid {
 484                 if new_set.seq_nr != media_set_label.seq_nr {
 485                     bail!("got media with wrong media sequence number ({} != {}",
 486                           new_set.seq_nr,media_set_label.seq_nr);
 487                 }
 488                 if new_set.encryption_key_fingerprint != media_set_label.encryption_key_fingerprint {
 489                     bail!("detected changed encryption fingerprint - internal error");
 490                 }
 491                 media_catalog = MediaCatalog::open(status_path, &media_id.label.uuid, true, false)?;
 492             } else {
 493                 worker.log(
 494                     format!("wrinting new media set label (overwrite '{}/{}')",
 495                             media_set_label.uuid.to_string(), media_set_label.seq_nr)
 496                 );
 497
 498                 drive.write_media_set_label(new_set, key_config.as_ref())?;
 499                 media_catalog = MediaCatalog::overwrite(status_path, media_id, false)?;
 500             }
 501         }
 502     }
 503
 504     // todo: verify last content/media_catalog somehow?
 505     drive.move_to_eom()?; // just to be sure
 506
 507     Ok(media_catalog)
 508 }