1 /* 2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. 3 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. 4 * 5 * This copyrighted material is made available to anyone wishing to use, 6 * modify, copy, or redistribute it subject to the terms and conditions 7 * of the GNU General Public License version 2. 8 */ 9 10 #ifndef __INCORE_DOT_H__ 11 #define __INCORE_DOT_H__ 12 13 #include <linux/fs.h> 14 #include <linux/kobject.h> 15 #include <linux/workqueue.h> 16 #include <linux/dlm.h> 17 #include <linux/buffer_head.h> 18 #include <linux/rcupdate.h> 19 #include <linux/rculist_bl.h> 20 21 #define DIO_WAIT 0x00000010 22 #define DIO_METADATA 0x00000020 23 #define DIO_ALL 0x00000100 24 25 struct gfs2_log_operations; 26 struct gfs2_log_element; 27 struct gfs2_holder; 28 struct gfs2_glock; 29 struct gfs2_quota_data; 30 struct gfs2_trans; 31 struct gfs2_ail; 32 struct gfs2_jdesc; 33 struct gfs2_sbd; 34 struct lm_lockops; 35 36 typedef void (*gfs2_glop_bh_t) (struct gfs2_glock *gl, unsigned int ret); 37 38 struct gfs2_log_header_host { 39 u64 lh_sequence; /* Sequence number of this transaction */ 40 u32 lh_flags; /* GFS2_LOG_HEAD_... */ 41 u32 lh_tail; /* Block number of log tail */ 42 u32 lh_blkno; 43 u32 lh_hash; 44 }; 45 46 /* 47 * Structure of operations that are associated with each 48 * type of element in the log. 49 */ 50 51 struct gfs2_log_operations { 52 void (*lo_add) (struct gfs2_sbd *sdp, struct gfs2_log_element *le); 53 void (*lo_before_commit) (struct gfs2_sbd *sdp); 54 void (*lo_after_commit) (struct gfs2_sbd *sdp, struct gfs2_ail *ai); 55 void (*lo_before_scan) (struct gfs2_jdesc *jd, 56 struct gfs2_log_header_host *head, int pass); 57 int (*lo_scan_elements) (struct gfs2_jdesc *jd, unsigned int start, 58 struct gfs2_log_descriptor *ld, __be64 *ptr, 59 int pass); 60 void (*lo_after_scan) (struct gfs2_jdesc *jd, int error, int pass); 61 const char *lo_name; 62 }; 63 64 struct gfs2_log_element { 65 struct list_head le_list; 66 const struct gfs2_log_operations *le_ops; 67 }; 68 69 #define GBF_FULL 1 70 71 struct gfs2_bitmap { 72 struct buffer_head *bi_bh; 73 char *bi_clone; 74 unsigned long bi_flags; 75 u32 bi_offset; 76 u32 bi_start; 77 u32 bi_len; 78 }; 79 80 struct gfs2_rgrpd { 81 struct list_head rd_list; /* Link with superblock */ 82 struct list_head rd_list_mru; 83 struct gfs2_glock *rd_gl; /* Glock for this rgrp */ 84 u64 rd_addr; /* grp block disk address */ 85 u64 rd_data0; /* first data location */ 86 u32 rd_length; /* length of rgrp header in fs blocks */ 87 u32 rd_data; /* num of data blocks in rgrp */ 88 u32 rd_bitbytes; /* number of bytes in data bitmaps */ 89 u32 rd_free; 90 u32 rd_free_clone; 91 u32 rd_dinodes; 92 u64 rd_igeneration; 93 struct gfs2_bitmap *rd_bits; 94 struct mutex rd_mutex; 95 struct gfs2_log_element rd_le; 96 struct gfs2_sbd *rd_sbd; 97 unsigned int rd_bh_count; 98 u32 rd_last_alloc; 99 u32 rd_flags; 100 #define GFS2_RDF_CHECK 0x10000000 /* check for unlinked inodes */ 101 #define GFS2_RDF_UPTODATE 0x20000000 /* rg is up to date */ 102 #define GFS2_RDF_ERROR 0x40000000 /* error in rg */ 103 #define GFS2_RDF_MASK 0xf0000000 /* mask for internal flags */ 104 }; 105 106 enum gfs2_state_bits { 107 BH_Pinned = BH_PrivateStart, 108 BH_Escaped = BH_PrivateStart + 1, 109 }; 110 111 BUFFER_FNS(Pinned, pinned) 112 TAS_BUFFER_FNS(Pinned, pinned) 113 BUFFER_FNS(Escaped, escaped) 114 TAS_BUFFER_FNS(Escaped, escaped) 115 116 struct gfs2_bufdata { 117 struct buffer_head *bd_bh; 118 struct gfs2_glock *bd_gl; 119 120 union { 121 struct list_head list_tr; 122 u64 blkno; 123 } u; 124 #define bd_list_tr u.list_tr 125 #define bd_blkno u.blkno 126 127 struct gfs2_log_element bd_le; 128 129 struct gfs2_ail *bd_ail; 130 struct list_head bd_ail_st_list; 131 struct list_head bd_ail_gl_list; 132 }; 133 134 /* 135 * Internally, we prefix things with gdlm_ and GDLM_ (for gfs-dlm) since a 136 * prefix of lock_dlm_ gets awkward. 137 */ 138 139 #define GDLM_STRNAME_BYTES 25 140 #define GDLM_LVB_SIZE 32 141 142 enum { 143 DFL_BLOCK_LOCKS = 0, 144 }; 145 146 struct lm_lockname { 147 u64 ln_number; 148 unsigned int ln_type; 149 }; 150 151 #define lm_name_equal(name1, name2) \ 152 (((name1)->ln_number == (name2)->ln_number) && \ 153 ((name1)->ln_type == (name2)->ln_type)) 154 155 156 struct gfs2_glock_operations { 157 void (*go_xmote_th) (struct gfs2_glock *gl); 158 int (*go_xmote_bh) (struct gfs2_glock *gl, struct gfs2_holder *gh); 159 void (*go_inval) (struct gfs2_glock *gl, int flags); 160 int (*go_demote_ok) (const struct gfs2_glock *gl); 161 int (*go_lock) (struct gfs2_holder *gh); 162 void (*go_unlock) (struct gfs2_holder *gh); 163 int (*go_dump)(struct seq_file *seq, const struct gfs2_glock *gl); 164 void (*go_callback) (struct gfs2_glock *gl); 165 const int go_type; 166 const unsigned long go_min_hold_time; 167 const unsigned long go_flags; 168 #define GLOF_ASPACE 1 169 }; 170 171 enum { 172 /* States */ 173 HIF_HOLDER = 6, /* Set for gh that "holds" the glock */ 174 HIF_FIRST = 7, 175 HIF_WAIT = 10, 176 }; 177 178 struct gfs2_holder { 179 struct list_head gh_list; 180 181 struct gfs2_glock *gh_gl; 182 struct pid *gh_owner_pid; 183 unsigned int gh_state; 184 unsigned gh_flags; 185 186 int gh_error; 187 unsigned long gh_iflags; /* HIF_... */ 188 unsigned long gh_ip; 189 }; 190 191 enum { 192 GLF_LOCK = 1, 193 GLF_DEMOTE = 3, 194 GLF_PENDING_DEMOTE = 4, 195 GLF_DEMOTE_IN_PROGRESS = 5, 196 GLF_DIRTY = 6, 197 GLF_LFLUSH = 7, 198 GLF_INVALIDATE_IN_PROGRESS = 8, 199 GLF_REPLY_PENDING = 9, 200 GLF_INITIAL = 10, 201 GLF_FROZEN = 11, 202 GLF_QUEUED = 12, 203 }; 204 205 struct gfs2_glock { 206 struct hlist_bl_node gl_list; 207 unsigned long gl_flags; /* GLF_... */ 208 struct lm_lockname gl_name; 209 atomic_t gl_ref; 210 211 spinlock_t gl_spin; 212 213 /* State fields protected by gl_spin */ 214 unsigned int gl_state:2, /* Current state */ 215 gl_target:2, /* Target state */ 216 gl_demote_state:2, /* State requested by remote node */ 217 gl_req:2, /* State in last dlm request */ 218 gl_reply:8; /* Last reply from the dlm */ 219 220 unsigned int gl_hash; 221 unsigned long gl_demote_time; /* time of first demote request */ 222 struct list_head gl_holders; 223 224 const struct gfs2_glock_operations *gl_ops; 225 char gl_strname[GDLM_STRNAME_BYTES]; 226 struct dlm_lksb gl_lksb; 227 char gl_lvb[32]; 228 unsigned long gl_tchange; 229 void *gl_object; 230 231 struct list_head gl_lru; 232 233 struct gfs2_sbd *gl_sbd; 234 235 struct list_head gl_ail_list; 236 atomic_t gl_ail_count; 237 struct delayed_work gl_work; 238 struct work_struct gl_delete; 239 struct rcu_head gl_rcu; 240 }; 241 242 #define GFS2_MIN_LVB_SIZE 32 /* Min size of LVB that gfs2 supports */ 243 244 struct gfs2_alloc { 245 /* Quota stuff */ 246 247 struct gfs2_quota_data *al_qd[2*MAXQUOTAS]; 248 struct gfs2_holder al_qd_ghs[2*MAXQUOTAS]; 249 unsigned int al_qd_num; 250 251 u32 al_requested; /* Filled in by caller of gfs2_inplace_reserve() */ 252 u32 al_alloced; /* Filled in by gfs2_alloc_*() */ 253 254 /* Filled in by gfs2_inplace_reserve() */ 255 256 unsigned int al_line; 257 char *al_file; 258 struct gfs2_holder al_ri_gh; 259 struct gfs2_holder al_rgd_gh; 260 struct gfs2_rgrpd *al_rgd; 261 262 }; 263 264 enum { 265 GIF_INVALID = 0, 266 GIF_QD_LOCKED = 1, 267 GIF_SW_PAGED = 3, 268 }; 269 270 271 struct gfs2_inode { 272 struct inode i_inode; 273 u64 i_no_addr; 274 u64 i_no_formal_ino; 275 u64 i_generation; 276 u64 i_eattr; 277 unsigned long i_flags; /* GIF_... */ 278 struct gfs2_glock *i_gl; /* Move into i_gh? */ 279 struct gfs2_holder i_iopen_gh; 280 struct gfs2_holder i_gh; /* for prepare/commit_write only */ 281 struct gfs2_alloc *i_alloc; 282 u64 i_goal; /* goal block for allocations */ 283 struct rw_semaphore i_rw_mutex; 284 struct list_head i_trunc_list; 285 u32 i_entries; 286 u32 i_diskflags; 287 u8 i_height; 288 u8 i_depth; 289 }; 290 291 /* 292 * Since i_inode is the first element of struct gfs2_inode, 293 * this is effectively a cast. 294 */ 295 static inline struct gfs2_inode *GFS2_I(struct inode *inode) 296 { 297 return container_of(inode, struct gfs2_inode, i_inode); 298 } 299 300 static inline struct gfs2_sbd *GFS2_SB(const struct inode *inode) 301 { 302 return inode->i_sb->s_fs_info; 303 } 304 305 struct gfs2_file { 306 struct mutex f_fl_mutex; 307 struct gfs2_holder f_fl_gh; 308 }; 309 310 struct gfs2_revoke_replay { 311 struct list_head rr_list; 312 u64 rr_blkno; 313 unsigned int rr_where; 314 }; 315 316 enum { 317 QDF_USER = 0, 318 QDF_CHANGE = 1, 319 QDF_LOCKED = 2, 320 QDF_REFRESH = 3, 321 }; 322 323 struct gfs2_quota_data { 324 struct list_head qd_list; 325 struct list_head qd_reclaim; 326 327 atomic_t qd_count; 328 329 u32 qd_id; 330 unsigned long qd_flags; /* QDF_... */ 331 332 s64 qd_change; 333 s64 qd_change_sync; 334 335 unsigned int qd_slot; 336 unsigned int qd_slot_count; 337 338 struct buffer_head *qd_bh; 339 struct gfs2_quota_change *qd_bh_qc; 340 unsigned int qd_bh_count; 341 342 struct gfs2_glock *qd_gl; 343 struct gfs2_quota_lvb qd_qb; 344 345 u64 qd_sync_gen; 346 unsigned long qd_last_warn; 347 }; 348 349 struct gfs2_trans { 350 unsigned long tr_ip; 351 352 unsigned int tr_blocks; 353 unsigned int tr_revokes; 354 unsigned int tr_reserved; 355 356 struct gfs2_holder tr_t_gh; 357 358 int tr_touched; 359 360 unsigned int tr_num_buf; 361 unsigned int tr_num_buf_new; 362 unsigned int tr_num_databuf_new; 363 unsigned int tr_num_buf_rm; 364 unsigned int tr_num_databuf_rm; 365 struct list_head tr_list_buf; 366 367 unsigned int tr_num_revoke; 368 unsigned int tr_num_revoke_rm; 369 }; 370 371 struct gfs2_ail { 372 struct list_head ai_list; 373 374 unsigned int ai_first; 375 struct list_head ai_ail1_list; 376 struct list_head ai_ail2_list; 377 378 u64 ai_sync_gen; 379 }; 380 381 struct gfs2_journal_extent { 382 struct list_head extent_list; 383 384 unsigned int lblock; /* First logical block */ 385 u64 dblock; /* First disk block */ 386 u64 blocks; 387 }; 388 389 struct gfs2_jdesc { 390 struct list_head jd_list; 391 struct list_head extent_list; 392 struct work_struct jd_work; 393 struct inode *jd_inode; 394 unsigned long jd_flags; 395 #define JDF_RECOVERY 1 396 unsigned int jd_jid; 397 unsigned int jd_blocks; 398 }; 399 400 struct gfs2_statfs_change_host { 401 s64 sc_total; 402 s64 sc_free; 403 s64 sc_dinodes; 404 }; 405 406 #define GFS2_QUOTA_DEFAULT GFS2_QUOTA_OFF 407 #define GFS2_QUOTA_OFF 0 408 #define GFS2_QUOTA_ACCOUNT 1 409 #define GFS2_QUOTA_ON 2 410 411 #define GFS2_DATA_DEFAULT GFS2_DATA_ORDERED 412 #define GFS2_DATA_WRITEBACK 1 413 #define GFS2_DATA_ORDERED 2 414 415 #define GFS2_ERRORS_DEFAULT GFS2_ERRORS_WITHDRAW 416 #define GFS2_ERRORS_WITHDRAW 0 417 #define GFS2_ERRORS_CONTINUE 1 /* place holder for future feature */ 418 #define GFS2_ERRORS_RO 2 /* place holder for future feature */ 419 #define GFS2_ERRORS_PANIC 3 420 421 struct gfs2_args { 422 char ar_lockproto[GFS2_LOCKNAME_LEN]; /* Name of the Lock Protocol */ 423 char ar_locktable[GFS2_LOCKNAME_LEN]; /* Name of the Lock Table */ 424 char ar_hostdata[GFS2_LOCKNAME_LEN]; /* Host specific data */ 425 unsigned int ar_spectator:1; /* Don't get a journal */ 426 unsigned int ar_localflocks:1; /* Let the VFS do flock|fcntl */ 427 unsigned int ar_debug:1; /* Oops on errors */ 428 unsigned int ar_posix_acl:1; /* Enable posix acls */ 429 unsigned int ar_quota:2; /* off/account/on */ 430 unsigned int ar_suiddir:1; /* suiddir support */ 431 unsigned int ar_data:2; /* ordered/writeback */ 432 unsigned int ar_meta:1; /* mount metafs */ 433 unsigned int ar_discard:1; /* discard requests */ 434 unsigned int ar_errors:2; /* errors=withdraw | panic */ 435 unsigned int ar_nobarrier:1; /* do not send barriers */ 436 int ar_commit; /* Commit interval */ 437 int ar_statfs_quantum; /* The fast statfs interval */ 438 int ar_quota_quantum; /* The quota interval */ 439 int ar_statfs_percent; /* The % change to force sync */ 440 }; 441 442 struct gfs2_tune { 443 spinlock_t gt_spin; 444 445 unsigned int gt_logd_secs; 446 447 unsigned int gt_quota_simul_sync; /* Max quotavals to sync at once */ 448 unsigned int gt_quota_warn_period; /* Secs between quota warn msgs */ 449 unsigned int gt_quota_scale_num; /* Numerator */ 450 unsigned int gt_quota_scale_den; /* Denominator */ 451 unsigned int gt_quota_quantum; /* Secs between syncs to quota file */ 452 unsigned int gt_new_files_jdata; 453 unsigned int gt_max_readahead; /* Max bytes to read-ahead from disk */ 454 unsigned int gt_complain_secs; 455 unsigned int gt_statfs_quantum; 456 unsigned int gt_statfs_slow; 457 }; 458 459 enum { 460 SDF_JOURNAL_CHECKED = 0, 461 SDF_JOURNAL_LIVE = 1, 462 SDF_SHUTDOWN = 2, 463 SDF_NOBARRIERS = 3, 464 SDF_NORECOVERY = 4, 465 SDF_DEMOTE = 5, 466 SDF_NOJOURNALID = 6, 467 }; 468 469 #define GFS2_FSNAME_LEN 256 470 471 struct gfs2_inum_host { 472 u64 no_formal_ino; 473 u64 no_addr; 474 }; 475 476 struct gfs2_sb_host { 477 u32 sb_magic; 478 u32 sb_type; 479 u32 sb_format; 480 481 u32 sb_fs_format; 482 u32 sb_multihost_format; 483 u32 sb_bsize; 484 u32 sb_bsize_shift; 485 486 struct gfs2_inum_host sb_master_dir; 487 struct gfs2_inum_host sb_root_dir; 488 489 char sb_lockproto[GFS2_LOCKNAME_LEN]; 490 char sb_locktable[GFS2_LOCKNAME_LEN]; 491 u8 sb_uuid[16]; 492 }; 493 494 /* 495 * lm_mount() return values 496 * 497 * ls_jid - the journal ID this node should use 498 * ls_first - this node is the first to mount the file system 499 * ls_lockspace - lock module's context for this file system 500 * ls_ops - lock module's functions 501 */ 502 503 struct lm_lockstruct { 504 int ls_jid; 505 unsigned int ls_first; 506 unsigned int ls_first_done; 507 unsigned int ls_nodir; 508 const struct lm_lockops *ls_ops; 509 unsigned long ls_flags; 510 dlm_lockspace_t *ls_dlm; 511 512 int ls_recover_jid_done; 513 int ls_recover_jid_status; 514 }; 515 516 struct gfs2_sbd { 517 struct super_block *sd_vfs; 518 struct kobject sd_kobj; 519 unsigned long sd_flags; /* SDF_... */ 520 struct gfs2_sb_host sd_sb; 521 522 /* Constants computed on mount */ 523 524 u32 sd_fsb2bb; 525 u32 sd_fsb2bb_shift; 526 u32 sd_diptrs; /* Number of pointers in a dinode */ 527 u32 sd_inptrs; /* Number of pointers in a indirect block */ 528 u32 sd_jbsize; /* Size of a journaled data block */ 529 u32 sd_hash_bsize; /* sizeof(exhash block) */ 530 u32 sd_hash_bsize_shift; 531 u32 sd_hash_ptrs; /* Number of pointers in a hash block */ 532 u32 sd_qc_per_block; 533 u32 sd_max_dirres; /* Max blocks needed to add a directory entry */ 534 u32 sd_max_height; /* Max height of a file's metadata tree */ 535 u64 sd_heightsize[GFS2_MAX_META_HEIGHT + 1]; 536 u32 sd_max_jheight; /* Max height of journaled file's meta tree */ 537 u64 sd_jheightsize[GFS2_MAX_META_HEIGHT + 1]; 538 539 struct gfs2_args sd_args; /* Mount arguments */ 540 struct gfs2_tune sd_tune; /* Filesystem tuning structure */ 541 542 /* Lock Stuff */ 543 544 struct lm_lockstruct sd_lockstruct; 545 struct gfs2_holder sd_live_gh; 546 struct gfs2_glock *sd_rename_gl; 547 struct gfs2_glock *sd_trans_gl; 548 wait_queue_head_t sd_glock_wait; 549 atomic_t sd_glock_disposal; 550 551 /* Inode Stuff */ 552 553 struct dentry *sd_master_dir; 554 struct dentry *sd_root_dir; 555 556 struct inode *sd_jindex; 557 struct inode *sd_statfs_inode; 558 struct inode *sd_sc_inode; 559 struct inode *sd_qc_inode; 560 struct inode *sd_rindex; 561 struct inode *sd_quota_inode; 562 563 /* StatFS stuff */ 564 565 spinlock_t sd_statfs_spin; 566 struct gfs2_statfs_change_host sd_statfs_master; 567 struct gfs2_statfs_change_host sd_statfs_local; 568 int sd_statfs_force_sync; 569 570 /* Resource group stuff */ 571 572 int sd_rindex_uptodate; 573 spinlock_t sd_rindex_spin; 574 struct mutex sd_rindex_mutex; 575 struct list_head sd_rindex_list; 576 struct list_head sd_rindex_mru_list; 577 struct gfs2_rgrpd *sd_rindex_forward; 578 unsigned int sd_rgrps; 579 unsigned int sd_max_rg_data; 580 581 /* Journal index stuff */ 582 583 struct list_head sd_jindex_list; 584 spinlock_t sd_jindex_spin; 585 struct mutex sd_jindex_mutex; 586 unsigned int sd_journals; 587 588 struct gfs2_jdesc *sd_jdesc; 589 struct gfs2_holder sd_journal_gh; 590 struct gfs2_holder sd_jinode_gh; 591 592 struct gfs2_holder sd_sc_gh; 593 struct gfs2_holder sd_qc_gh; 594 595 /* Daemon stuff */ 596 597 struct task_struct *sd_logd_process; 598 struct task_struct *sd_quotad_process; 599 600 /* Quota stuff */ 601 602 struct list_head sd_quota_list; 603 atomic_t sd_quota_count; 604 struct mutex sd_quota_mutex; 605 wait_queue_head_t sd_quota_wait; 606 struct list_head sd_trunc_list; 607 spinlock_t sd_trunc_lock; 608 609 unsigned int sd_quota_slots; 610 unsigned int sd_quota_chunks; 611 unsigned char **sd_quota_bitmap; 612 613 u64 sd_quota_sync_gen; 614 615 /* Log stuff */ 616 617 spinlock_t sd_log_lock; 618 619 unsigned int sd_log_blks_reserved; 620 unsigned int sd_log_commited_buf; 621 unsigned int sd_log_commited_databuf; 622 int sd_log_commited_revoke; 623 624 atomic_t sd_log_pinned; 625 unsigned int sd_log_num_buf; 626 unsigned int sd_log_num_revoke; 627 unsigned int sd_log_num_rg; 628 unsigned int sd_log_num_databuf; 629 630 struct list_head sd_log_le_buf; 631 struct list_head sd_log_le_revoke; 632 struct list_head sd_log_le_rg; 633 struct list_head sd_log_le_databuf; 634 struct list_head sd_log_le_ordered; 635 636 atomic_t sd_log_thresh1; 637 atomic_t sd_log_thresh2; 638 atomic_t sd_log_blks_free; 639 wait_queue_head_t sd_log_waitq; 640 wait_queue_head_t sd_logd_waitq; 641 642 u64 sd_log_sequence; 643 unsigned int sd_log_head; 644 unsigned int sd_log_tail; 645 int sd_log_idle; 646 647 struct rw_semaphore sd_log_flush_lock; 648 atomic_t sd_log_in_flight; 649 wait_queue_head_t sd_log_flush_wait; 650 651 unsigned int sd_log_flush_head; 652 u64 sd_log_flush_wrapped; 653 654 spinlock_t sd_ail_lock; 655 struct list_head sd_ail1_list; 656 struct list_head sd_ail2_list; 657 u64 sd_ail_sync_gen; 658 659 /* Replay stuff */ 660 661 struct list_head sd_revoke_list; 662 unsigned int sd_replay_tail; 663 664 unsigned int sd_found_blocks; 665 unsigned int sd_found_revokes; 666 unsigned int sd_replayed_blocks; 667 668 /* For quiescing the filesystem */ 669 670 struct gfs2_holder sd_freeze_gh; 671 struct mutex sd_freeze_lock; 672 unsigned int sd_freeze_count; 673 674 char sd_fsname[GFS2_FSNAME_LEN]; 675 char sd_table_name[GFS2_FSNAME_LEN]; 676 char sd_proto_name[GFS2_FSNAME_LEN]; 677 678 /* Debugging crud */ 679 680 unsigned long sd_last_warning; 681 struct dentry *debugfs_dir; /* debugfs directory */ 682 struct dentry *debugfs_dentry_glocks; /* for debugfs */ 683 }; 684 685 #endif /* __INCORE_DOT_H__ */ 686 687