1 /* 2 * Copyright (c) 2000-2005 Silicon Graphics, Inc. 3 * All Rights Reserved. 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it would be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18 #include "xfs.h" 19 #include "xfs_fs.h" 20 #include "xfs_types.h" 21 #include "xfs_bit.h" 22 #include "xfs_log.h" 23 #include "xfs_inum.h" 24 #include "xfs_trans.h" 25 #include "xfs_sb.h" 26 #include "xfs_ag.h" 27 #include "xfs_mount.h" 28 #include "xfs_error.h" 29 #include "xfs_log_priv.h" 30 #include "xfs_buf_item.h" 31 #include "xfs_bmap_btree.h" 32 #include "xfs_alloc_btree.h" 33 #include "xfs_ialloc_btree.h" 34 #include "xfs_log_recover.h" 35 #include "xfs_trans_priv.h" 36 #include "xfs_dinode.h" 37 #include "xfs_inode.h" 38 #include "xfs_rw.h" 39 #include "xfs_trace.h" 40 41 kmem_zone_t *xfs_log_ticket_zone; 42 43 /* Local miscellaneous function prototypes */ 44 STATIC int xlog_commit_record(struct log *log, struct xlog_ticket *ticket, 45 xlog_in_core_t **, xfs_lsn_t *); 46 STATIC xlog_t * xlog_alloc_log(xfs_mount_t *mp, 47 xfs_buftarg_t *log_target, 48 xfs_daddr_t blk_offset, 49 int num_bblks); 50 STATIC int xlog_space_left(struct log *log, atomic64_t *head); 51 STATIC int xlog_sync(xlog_t *log, xlog_in_core_t *iclog); 52 STATIC void xlog_dealloc_log(xlog_t *log); 53 54 /* local state machine functions */ 55 STATIC void xlog_state_done_syncing(xlog_in_core_t *iclog, int); 56 STATIC void xlog_state_do_callback(xlog_t *log,int aborted, xlog_in_core_t *iclog); 57 STATIC int xlog_state_get_iclog_space(xlog_t *log, 58 int len, 59 xlog_in_core_t **iclog, 60 xlog_ticket_t *ticket, 61 int *continued_write, 62 int *logoffsetp); 63 STATIC int xlog_state_release_iclog(xlog_t *log, 64 xlog_in_core_t *iclog); 65 STATIC void xlog_state_switch_iclogs(xlog_t *log, 66 xlog_in_core_t *iclog, 67 int eventual_size); 68 STATIC void xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog); 69 70 STATIC void xlog_grant_push_ail(struct log *log, 71 int need_bytes); 72 STATIC void xlog_regrant_reserve_log_space(xlog_t *log, 73 xlog_ticket_t *ticket); 74 STATIC void xlog_ungrant_log_space(xlog_t *log, 75 xlog_ticket_t *ticket); 76 77 #if defined(DEBUG) 78 STATIC void xlog_verify_dest_ptr(xlog_t *log, char *ptr); 79 STATIC void xlog_verify_grant_tail(struct log *log); 80 STATIC void xlog_verify_iclog(xlog_t *log, xlog_in_core_t *iclog, 81 int count, boolean_t syncing); 82 STATIC void xlog_verify_tail_lsn(xlog_t *log, xlog_in_core_t *iclog, 83 xfs_lsn_t tail_lsn); 84 #else 85 #define xlog_verify_dest_ptr(a,b) 86 #define xlog_verify_grant_tail(a) 87 #define xlog_verify_iclog(a,b,c,d) 88 #define xlog_verify_tail_lsn(a,b,c) 89 #endif 90 91 STATIC int xlog_iclogs_empty(xlog_t *log); 92 93 static void 94 xlog_grant_sub_space( 95 struct log *log, 96 atomic64_t *head, 97 int bytes) 98 { 99 int64_t head_val = atomic64_read(head); 100 int64_t new, old; 101 102 do { 103 int cycle, space; 104 105 xlog_crack_grant_head_val(head_val, &cycle, &space); 106 107 space -= bytes; 108 if (space < 0) { 109 space += log->l_logsize; 110 cycle--; 111 } 112 113 old = head_val; 114 new = xlog_assign_grant_head_val(cycle, space); 115 head_val = atomic64_cmpxchg(head, old, new); 116 } while (head_val != old); 117 } 118 119 static void 120 xlog_grant_add_space( 121 struct log *log, 122 atomic64_t *head, 123 int bytes) 124 { 125 int64_t head_val = atomic64_read(head); 126 int64_t new, old; 127 128 do { 129 int tmp; 130 int cycle, space; 131 132 xlog_crack_grant_head_val(head_val, &cycle, &space); 133 134 tmp = log->l_logsize - space; 135 if (tmp > bytes) 136 space += bytes; 137 else { 138 space = bytes - tmp; 139 cycle++; 140 } 141 142 old = head_val; 143 new = xlog_assign_grant_head_val(cycle, space); 144 head_val = atomic64_cmpxchg(head, old, new); 145 } while (head_val != old); 146 } 147 148 STATIC void 149 xlog_grant_head_init( 150 struct xlog_grant_head *head) 151 { 152 xlog_assign_grant_head(&head->grant, 1, 0); 153 INIT_LIST_HEAD(&head->waiters); 154 spin_lock_init(&head->lock); 155 } 156 157 STATIC void 158 xlog_grant_head_wake_all( 159 struct xlog_grant_head *head) 160 { 161 struct xlog_ticket *tic; 162 163 spin_lock(&head->lock); 164 list_for_each_entry(tic, &head->waiters, t_queue) 165 wake_up_process(tic->t_task); 166 spin_unlock(&head->lock); 167 } 168 169 static inline int 170 xlog_ticket_reservation( 171 struct log *log, 172 struct xlog_grant_head *head, 173 struct xlog_ticket *tic) 174 { 175 if (head == &log->l_write_head) { 176 ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV); 177 return tic->t_unit_res; 178 } else { 179 if (tic->t_flags & XLOG_TIC_PERM_RESERV) 180 return tic->t_unit_res * tic->t_cnt; 181 else 182 return tic->t_unit_res; 183 } 184 } 185 186 STATIC bool 187 xlog_grant_head_wake( 188 struct log *log, 189 struct xlog_grant_head *head, 190 int *free_bytes) 191 { 192 struct xlog_ticket *tic; 193 int need_bytes; 194 195 list_for_each_entry(tic, &head->waiters, t_queue) { 196 need_bytes = xlog_ticket_reservation(log, head, tic); 197 if (*free_bytes < need_bytes) 198 return false; 199 200 *free_bytes -= need_bytes; 201 trace_xfs_log_grant_wake_up(log, tic); 202 wake_up_process(tic->t_task); 203 } 204 205 return true; 206 } 207 208 STATIC int 209 xlog_grant_head_wait( 210 struct log *log, 211 struct xlog_grant_head *head, 212 struct xlog_ticket *tic, 213 int need_bytes) 214 { 215 list_add_tail(&tic->t_queue, &head->waiters); 216 217 do { 218 if (XLOG_FORCED_SHUTDOWN(log)) 219 goto shutdown; 220 xlog_grant_push_ail(log, need_bytes); 221 222 __set_current_state(TASK_UNINTERRUPTIBLE); 223 spin_unlock(&head->lock); 224 225 XFS_STATS_INC(xs_sleep_logspace); 226 227 trace_xfs_log_grant_sleep(log, tic); 228 schedule(); 229 trace_xfs_log_grant_wake(log, tic); 230 231 spin_lock(&head->lock); 232 if (XLOG_FORCED_SHUTDOWN(log)) 233 goto shutdown; 234 } while (xlog_space_left(log, &head->grant) < need_bytes); 235 236 list_del_init(&tic->t_queue); 237 return 0; 238 shutdown: 239 list_del_init(&tic->t_queue); 240 return XFS_ERROR(EIO); 241 } 242 243 /* 244 * Atomically get the log space required for a log ticket. 245 * 246 * Once a ticket gets put onto head->waiters, it will only return after the 247 * needed reservation is satisfied. 248 * 249 * This function is structured so that it has a lock free fast path. This is 250 * necessary because every new transaction reservation will come through this 251 * path. Hence any lock will be globally hot if we take it unconditionally on 252 * every pass. 253 * 254 * As tickets are only ever moved on and off head->waiters under head->lock, we 255 * only need to take that lock if we are going to add the ticket to the queue 256 * and sleep. We can avoid taking the lock if the ticket was never added to 257 * head->waiters because the t_queue list head will be empty and we hold the 258 * only reference to it so it can safely be checked unlocked. 259 */ 260 STATIC int 261 xlog_grant_head_check( 262 struct log *log, 263 struct xlog_grant_head *head, 264 struct xlog_ticket *tic, 265 int *need_bytes) 266 { 267 int free_bytes; 268 int error = 0; 269 270 ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY)); 271 272 /* 273 * If there are other waiters on the queue then give them a chance at 274 * logspace before us. Wake up the first waiters, if we do not wake 275 * up all the waiters then go to sleep waiting for more free space, 276 * otherwise try to get some space for this transaction. 277 */ 278 *need_bytes = xlog_ticket_reservation(log, head, tic); 279 free_bytes = xlog_space_left(log, &head->grant); 280 if (!list_empty_careful(&head->waiters)) { 281 spin_lock(&head->lock); 282 if (!xlog_grant_head_wake(log, head, &free_bytes) || 283 free_bytes < *need_bytes) { 284 error = xlog_grant_head_wait(log, head, tic, 285 *need_bytes); 286 } 287 spin_unlock(&head->lock); 288 } else if (free_bytes < *need_bytes) { 289 spin_lock(&head->lock); 290 error = xlog_grant_head_wait(log, head, tic, *need_bytes); 291 spin_unlock(&head->lock); 292 } 293 294 return error; 295 } 296 297 static void 298 xlog_tic_reset_res(xlog_ticket_t *tic) 299 { 300 tic->t_res_num = 0; 301 tic->t_res_arr_sum = 0; 302 tic->t_res_num_ophdrs = 0; 303 } 304 305 static void 306 xlog_tic_add_region(xlog_ticket_t *tic, uint len, uint type) 307 { 308 if (tic->t_res_num == XLOG_TIC_LEN_MAX) { 309 /* add to overflow and start again */ 310 tic->t_res_o_flow += tic->t_res_arr_sum; 311 tic->t_res_num = 0; 312 tic->t_res_arr_sum = 0; 313 } 314 315 tic->t_res_arr[tic->t_res_num].r_len = len; 316 tic->t_res_arr[tic->t_res_num].r_type = type; 317 tic->t_res_arr_sum += len; 318 tic->t_res_num++; 319 } 320 321 /* 322 * Replenish the byte reservation required by moving the grant write head. 323 */ 324 int 325 xfs_log_regrant( 326 struct xfs_mount *mp, 327 struct xlog_ticket *tic) 328 { 329 struct log *log = mp->m_log; 330 int need_bytes; 331 int error = 0; 332 333 if (XLOG_FORCED_SHUTDOWN(log)) 334 return XFS_ERROR(EIO); 335 336 XFS_STATS_INC(xs_try_logspace); 337 338 /* 339 * This is a new transaction on the ticket, so we need to change the 340 * transaction ID so that the next transaction has a different TID in 341 * the log. Just add one to the existing tid so that we can see chains 342 * of rolling transactions in the log easily. 343 */ 344 tic->t_tid++; 345 346 xlog_grant_push_ail(log, tic->t_unit_res); 347 348 tic->t_curr_res = tic->t_unit_res; 349 xlog_tic_reset_res(tic); 350 351 if (tic->t_cnt > 0) 352 return 0; 353 354 trace_xfs_log_regrant(log, tic); 355 356 error = xlog_grant_head_check(log, &log->l_write_head, tic, 357 &need_bytes); 358 if (error) 359 goto out_error; 360 361 xlog_grant_add_space(log, &log->l_write_head.grant, need_bytes); 362 trace_xfs_log_regrant_exit(log, tic); 363 xlog_verify_grant_tail(log); 364 return 0; 365 366 out_error: 367 /* 368 * If we are failing, make sure the ticket doesn't have any current 369 * reservations. We don't want to add this back when the ticket/ 370 * transaction gets cancelled. 371 */ 372 tic->t_curr_res = 0; 373 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */ 374 return error; 375 } 376 377 /* 378 * Reserve log space and return a ticket corresponding the reservation. 379 * 380 * Each reservation is going to reserve extra space for a log record header. 381 * When writes happen to the on-disk log, we don't subtract the length of the 382 * log record header from any reservation. By wasting space in each 383 * reservation, we prevent over allocation problems. 384 */ 385 int 386 xfs_log_reserve( 387 struct xfs_mount *mp, 388 int unit_bytes, 389 int cnt, 390 struct xlog_ticket **ticp, 391 __uint8_t client, 392 bool permanent, 393 uint t_type) 394 { 395 struct log *log = mp->m_log; 396 struct xlog_ticket *tic; 397 int need_bytes; 398 int error = 0; 399 400 ASSERT(client == XFS_TRANSACTION || client == XFS_LOG); 401 402 if (XLOG_FORCED_SHUTDOWN(log)) 403 return XFS_ERROR(EIO); 404 405 XFS_STATS_INC(xs_try_logspace); 406 407 ASSERT(*ticp == NULL); 408 tic = xlog_ticket_alloc(log, unit_bytes, cnt, client, permanent, 409 KM_SLEEP | KM_MAYFAIL); 410 if (!tic) 411 return XFS_ERROR(ENOMEM); 412 413 tic->t_trans_type = t_type; 414 *ticp = tic; 415 416 xlog_grant_push_ail(log, tic->t_unit_res * tic->t_cnt); 417 418 trace_xfs_log_reserve(log, tic); 419 420 error = xlog_grant_head_check(log, &log->l_reserve_head, tic, 421 &need_bytes); 422 if (error) 423 goto out_error; 424 425 xlog_grant_add_space(log, &log->l_reserve_head.grant, need_bytes); 426 xlog_grant_add_space(log, &log->l_write_head.grant, need_bytes); 427 trace_xfs_log_reserve_exit(log, tic); 428 xlog_verify_grant_tail(log); 429 return 0; 430 431 out_error: 432 /* 433 * If we are failing, make sure the ticket doesn't have any current 434 * reservations. We don't want to add this back when the ticket/ 435 * transaction gets cancelled. 436 */ 437 tic->t_curr_res = 0; 438 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */ 439 return error; 440 } 441 442 443 /* 444 * NOTES: 445 * 446 * 1. currblock field gets updated at startup and after in-core logs 447 * marked as with WANT_SYNC. 448 */ 449 450 /* 451 * This routine is called when a user of a log manager ticket is done with 452 * the reservation. If the ticket was ever used, then a commit record for 453 * the associated transaction is written out as a log operation header with 454 * no data. The flag XLOG_TIC_INITED is set when the first write occurs with 455 * a given ticket. If the ticket was one with a permanent reservation, then 456 * a few operations are done differently. Permanent reservation tickets by 457 * default don't release the reservation. They just commit the current 458 * transaction with the belief that the reservation is still needed. A flag 459 * must be passed in before permanent reservations are actually released. 460 * When these type of tickets are not released, they need to be set into 461 * the inited state again. By doing this, a start record will be written 462 * out when the next write occurs. 463 */ 464 xfs_lsn_t 465 xfs_log_done( 466 struct xfs_mount *mp, 467 struct xlog_ticket *ticket, 468 struct xlog_in_core **iclog, 469 uint flags) 470 { 471 struct log *log = mp->m_log; 472 xfs_lsn_t lsn = 0; 473 474 if (XLOG_FORCED_SHUTDOWN(log) || 475 /* 476 * If nothing was ever written, don't write out commit record. 477 * If we get an error, just continue and give back the log ticket. 478 */ 479 (((ticket->t_flags & XLOG_TIC_INITED) == 0) && 480 (xlog_commit_record(log, ticket, iclog, &lsn)))) { 481 lsn = (xfs_lsn_t) -1; 482 if (ticket->t_flags & XLOG_TIC_PERM_RESERV) { 483 flags |= XFS_LOG_REL_PERM_RESERV; 484 } 485 } 486 487 488 if ((ticket->t_flags & XLOG_TIC_PERM_RESERV) == 0 || 489 (flags & XFS_LOG_REL_PERM_RESERV)) { 490 trace_xfs_log_done_nonperm(log, ticket); 491 492 /* 493 * Release ticket if not permanent reservation or a specific 494 * request has been made to release a permanent reservation. 495 */ 496 xlog_ungrant_log_space(log, ticket); 497 xfs_log_ticket_put(ticket); 498 } else { 499 trace_xfs_log_done_perm(log, ticket); 500 501 xlog_regrant_reserve_log_space(log, ticket); 502 /* If this ticket was a permanent reservation and we aren't 503 * trying to release it, reset the inited flags; so next time 504 * we write, a start record will be written out. 505 */ 506 ticket->t_flags |= XLOG_TIC_INITED; 507 } 508 509 return lsn; 510 } 511 512 /* 513 * Attaches a new iclog I/O completion callback routine during 514 * transaction commit. If the log is in error state, a non-zero 515 * return code is handed back and the caller is responsible for 516 * executing the callback at an appropriate time. 517 */ 518 int 519 xfs_log_notify( 520 struct xfs_mount *mp, 521 struct xlog_in_core *iclog, 522 xfs_log_callback_t *cb) 523 { 524 int abortflg; 525 526 spin_lock(&iclog->ic_callback_lock); 527 abortflg = (iclog->ic_state & XLOG_STATE_IOERROR); 528 if (!abortflg) { 529 ASSERT_ALWAYS((iclog->ic_state == XLOG_STATE_ACTIVE) || 530 (iclog->ic_state == XLOG_STATE_WANT_SYNC)); 531 cb->cb_next = NULL; 532 *(iclog->ic_callback_tail) = cb; 533 iclog->ic_callback_tail = &(cb->cb_next); 534 } 535 spin_unlock(&iclog->ic_callback_lock); 536 return abortflg; 537 } 538 539 int 540 xfs_log_release_iclog( 541 struct xfs_mount *mp, 542 struct xlog_in_core *iclog) 543 { 544 if (xlog_state_release_iclog(mp->m_log, iclog)) { 545 xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR); 546 return EIO; 547 } 548 549 return 0; 550 } 551 552 /* 553 * Mount a log filesystem 554 * 555 * mp - ubiquitous xfs mount point structure 556 * log_target - buftarg of on-disk log device 557 * blk_offset - Start block # where block size is 512 bytes (BBSIZE) 558 * num_bblocks - Number of BBSIZE blocks in on-disk log 559 * 560 * Return error or zero. 561 */ 562 int 563 xfs_log_mount( 564 xfs_mount_t *mp, 565 xfs_buftarg_t *log_target, 566 xfs_daddr_t blk_offset, 567 int num_bblks) 568 { 569 int error; 570 571 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) 572 xfs_notice(mp, "Mounting Filesystem"); 573 else { 574 xfs_notice(mp, 575 "Mounting filesystem in no-recovery mode. Filesystem will be inconsistent."); 576 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY); 577 } 578 579 mp->m_log = xlog_alloc_log(mp, log_target, blk_offset, num_bblks); 580 if (IS_ERR(mp->m_log)) { 581 error = -PTR_ERR(mp->m_log); 582 goto out; 583 } 584 585 /* 586 * Initialize the AIL now we have a log. 587 */ 588 error = xfs_trans_ail_init(mp); 589 if (error) { 590 xfs_warn(mp, "AIL initialisation failed: error %d", error); 591 goto out_free_log; 592 } 593 mp->m_log->l_ailp = mp->m_ail; 594 595 /* 596 * skip log recovery on a norecovery mount. pretend it all 597 * just worked. 598 */ 599 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) { 600 int readonly = (mp->m_flags & XFS_MOUNT_RDONLY); 601 602 if (readonly) 603 mp->m_flags &= ~XFS_MOUNT_RDONLY; 604 605 error = xlog_recover(mp->m_log); 606 607 if (readonly) 608 mp->m_flags |= XFS_MOUNT_RDONLY; 609 if (error) { 610 xfs_warn(mp, "log mount/recovery failed: error %d", 611 error); 612 goto out_destroy_ail; 613 } 614 } 615 616 /* Normal transactions can now occur */ 617 mp->m_log->l_flags &= ~XLOG_ACTIVE_RECOVERY; 618 619 /* 620 * Now the log has been fully initialised and we know were our 621 * space grant counters are, we can initialise the permanent ticket 622 * needed for delayed logging to work. 623 */ 624 xlog_cil_init_post_recovery(mp->m_log); 625 626 return 0; 627 628 out_destroy_ail: 629 xfs_trans_ail_destroy(mp); 630 out_free_log: 631 xlog_dealloc_log(mp->m_log); 632 out: 633 return error; 634 } 635 636 /* 637 * Finish the recovery of the file system. This is separate from 638 * the xfs_log_mount() call, because it depends on the code in 639 * xfs_mountfs() to read in the root and real-time bitmap inodes 640 * between calling xfs_log_mount() and here. 641 * 642 * mp - ubiquitous xfs mount point structure 643 */ 644 int 645 xfs_log_mount_finish(xfs_mount_t *mp) 646 { 647 int error; 648 649 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) 650 error = xlog_recover_finish(mp->m_log); 651 else { 652 error = 0; 653 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY); 654 } 655 656 return error; 657 } 658 659 /* 660 * Final log writes as part of unmount. 661 * 662 * Mark the filesystem clean as unmount happens. Note that during relocation 663 * this routine needs to be executed as part of source-bag while the 664 * deallocation must not be done until source-end. 665 */ 666 667 /* 668 * Unmount record used to have a string "Unmount filesystem--" in the 669 * data section where the "Un" was really a magic number (XLOG_UNMOUNT_TYPE). 670 * We just write the magic number now since that particular field isn't 671 * currently architecture converted and "nUmount" is a bit foo. 672 * As far as I know, there weren't any dependencies on the old behaviour. 673 */ 674 675 int 676 xfs_log_unmount_write(xfs_mount_t *mp) 677 { 678 xlog_t *log = mp->m_log; 679 xlog_in_core_t *iclog; 680 #ifdef DEBUG 681 xlog_in_core_t *first_iclog; 682 #endif 683 xlog_ticket_t *tic = NULL; 684 xfs_lsn_t lsn; 685 int error; 686 687 /* 688 * Don't write out unmount record on read-only mounts. 689 * Or, if we are doing a forced umount (typically because of IO errors). 690 */ 691 if (mp->m_flags & XFS_MOUNT_RDONLY) 692 return 0; 693 694 error = _xfs_log_force(mp, XFS_LOG_SYNC, NULL); 695 ASSERT(error || !(XLOG_FORCED_SHUTDOWN(log))); 696 697 #ifdef DEBUG 698 first_iclog = iclog = log->l_iclog; 699 do { 700 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) { 701 ASSERT(iclog->ic_state & XLOG_STATE_ACTIVE); 702 ASSERT(iclog->ic_offset == 0); 703 } 704 iclog = iclog->ic_next; 705 } while (iclog != first_iclog); 706 #endif 707 if (! (XLOG_FORCED_SHUTDOWN(log))) { 708 error = xfs_log_reserve(mp, 600, 1, &tic, 709 XFS_LOG, 0, XLOG_UNMOUNT_REC_TYPE); 710 if (!error) { 711 /* the data section must be 32 bit size aligned */ 712 struct { 713 __uint16_t magic; 714 __uint16_t pad1; 715 __uint32_t pad2; /* may as well make it 64 bits */ 716 } magic = { 717 .magic = XLOG_UNMOUNT_TYPE, 718 }; 719 struct xfs_log_iovec reg = { 720 .i_addr = &magic, 721 .i_len = sizeof(magic), 722 .i_type = XLOG_REG_TYPE_UNMOUNT, 723 }; 724 struct xfs_log_vec vec = { 725 .lv_niovecs = 1, 726 .lv_iovecp = ®, 727 }; 728 729 /* remove inited flag, and account for space used */ 730 tic->t_flags = 0; 731 tic->t_curr_res -= sizeof(magic); 732 error = xlog_write(log, &vec, tic, &lsn, 733 NULL, XLOG_UNMOUNT_TRANS); 734 /* 735 * At this point, we're umounting anyway, 736 * so there's no point in transitioning log state 737 * to IOERROR. Just continue... 738 */ 739 } 740 741 if (error) 742 xfs_alert(mp, "%s: unmount record failed", __func__); 743 744 745 spin_lock(&log->l_icloglock); 746 iclog = log->l_iclog; 747 atomic_inc(&iclog->ic_refcnt); 748 xlog_state_want_sync(log, iclog); 749 spin_unlock(&log->l_icloglock); 750 error = xlog_state_release_iclog(log, iclog); 751 752 spin_lock(&log->l_icloglock); 753 if (!(iclog->ic_state == XLOG_STATE_ACTIVE || 754 iclog->ic_state == XLOG_STATE_DIRTY)) { 755 if (!XLOG_FORCED_SHUTDOWN(log)) { 756 xlog_wait(&iclog->ic_force_wait, 757 &log->l_icloglock); 758 } else { 759 spin_unlock(&log->l_icloglock); 760 } 761 } else { 762 spin_unlock(&log->l_icloglock); 763 } 764 if (tic) { 765 trace_xfs_log_umount_write(log, tic); 766 xlog_ungrant_log_space(log, tic); 767 xfs_log_ticket_put(tic); 768 } 769 } else { 770 /* 771 * We're already in forced_shutdown mode, couldn't 772 * even attempt to write out the unmount transaction. 773 * 774 * Go through the motions of sync'ing and releasing 775 * the iclog, even though no I/O will actually happen, 776 * we need to wait for other log I/Os that may already 777 * be in progress. Do this as a separate section of 778 * code so we'll know if we ever get stuck here that 779 * we're in this odd situation of trying to unmount 780 * a file system that went into forced_shutdown as 781 * the result of an unmount.. 782 */ 783 spin_lock(&log->l_icloglock); 784 iclog = log->l_iclog; 785 atomic_inc(&iclog->ic_refcnt); 786 787 xlog_state_want_sync(log, iclog); 788 spin_unlock(&log->l_icloglock); 789 error = xlog_state_release_iclog(log, iclog); 790 791 spin_lock(&log->l_icloglock); 792 793 if ( ! ( iclog->ic_state == XLOG_STATE_ACTIVE 794 || iclog->ic_state == XLOG_STATE_DIRTY 795 || iclog->ic_state == XLOG_STATE_IOERROR) ) { 796 797 xlog_wait(&iclog->ic_force_wait, 798 &log->l_icloglock); 799 } else { 800 spin_unlock(&log->l_icloglock); 801 } 802 } 803 804 return error; 805 } /* xfs_log_unmount_write */ 806 807 /* 808 * Deallocate log structures for unmount/relocation. 809 * 810 * We need to stop the aild from running before we destroy 811 * and deallocate the log as the aild references the log. 812 */ 813 void 814 xfs_log_unmount(xfs_mount_t *mp) 815 { 816 xfs_trans_ail_destroy(mp); 817 xlog_dealloc_log(mp->m_log); 818 } 819 820 void 821 xfs_log_item_init( 822 struct xfs_mount *mp, 823 struct xfs_log_item *item, 824 int type, 825 const struct xfs_item_ops *ops) 826 { 827 item->li_mountp = mp; 828 item->li_ailp = mp->m_ail; 829 item->li_type = type; 830 item->li_ops = ops; 831 item->li_lv = NULL; 832 833 INIT_LIST_HEAD(&item->li_ail); 834 INIT_LIST_HEAD(&item->li_cil); 835 } 836 837 /* 838 * Wake up processes waiting for log space after we have moved the log tail. 839 */ 840 void 841 xfs_log_space_wake( 842 struct xfs_mount *mp) 843 { 844 struct log *log = mp->m_log; 845 int free_bytes; 846 847 if (XLOG_FORCED_SHUTDOWN(log)) 848 return; 849 850 if (!list_empty_careful(&log->l_write_head.waiters)) { 851 ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY)); 852 853 spin_lock(&log->l_write_head.lock); 854 free_bytes = xlog_space_left(log, &log->l_write_head.grant); 855 xlog_grant_head_wake(log, &log->l_write_head, &free_bytes); 856 spin_unlock(&log->l_write_head.lock); 857 } 858 859 if (!list_empty_careful(&log->l_reserve_head.waiters)) { 860 ASSERT(!(log->l_flags & XLOG_ACTIVE_RECOVERY)); 861 862 spin_lock(&log->l_reserve_head.lock); 863 free_bytes = xlog_space_left(log, &log->l_reserve_head.grant); 864 xlog_grant_head_wake(log, &log->l_reserve_head, &free_bytes); 865 spin_unlock(&log->l_reserve_head.lock); 866 } 867 } 868 869 /* 870 * Determine if we have a transaction that has gone to disk 871 * that needs to be covered. To begin the transition to the idle state 872 * firstly the log needs to be idle (no AIL and nothing in the iclogs). 873 * If we are then in a state where covering is needed, the caller is informed 874 * that dummy transactions are required to move the log into the idle state. 875 * 876 * Because this is called as part of the sync process, we should also indicate 877 * that dummy transactions should be issued in anything but the covered or 878 * idle states. This ensures that the log tail is accurately reflected in 879 * the log at the end of the sync, hence if a crash occurrs avoids replay 880 * of transactions where the metadata is already on disk. 881 */ 882 int 883 xfs_log_need_covered(xfs_mount_t *mp) 884 { 885 int needed = 0; 886 xlog_t *log = mp->m_log; 887 888 if (!xfs_fs_writable(mp)) 889 return 0; 890 891 spin_lock(&log->l_icloglock); 892 switch (log->l_covered_state) { 893 case XLOG_STATE_COVER_DONE: 894 case XLOG_STATE_COVER_DONE2: 895 case XLOG_STATE_COVER_IDLE: 896 break; 897 case XLOG_STATE_COVER_NEED: 898 case XLOG_STATE_COVER_NEED2: 899 if (!xfs_ail_min_lsn(log->l_ailp) && 900 xlog_iclogs_empty(log)) { 901 if (log->l_covered_state == XLOG_STATE_COVER_NEED) 902 log->l_covered_state = XLOG_STATE_COVER_DONE; 903 else 904 log->l_covered_state = XLOG_STATE_COVER_DONE2; 905 } 906 /* FALLTHRU */ 907 default: 908 needed = 1; 909 break; 910 } 911 spin_unlock(&log->l_icloglock); 912 return needed; 913 } 914 915 /* 916 * We may be holding the log iclog lock upon entering this routine. 917 */ 918 xfs_lsn_t 919 xlog_assign_tail_lsn( 920 struct xfs_mount *mp) 921 { 922 xfs_lsn_t tail_lsn; 923 struct log *log = mp->m_log; 924 925 /* 926 * To make sure we always have a valid LSN for the log tail we keep 927 * track of the last LSN which was committed in log->l_last_sync_lsn, 928 * and use that when the AIL was empty and xfs_ail_min_lsn returns 0. 929 * 930 * If the AIL has been emptied we also need to wake any process 931 * waiting for this condition. 932 */ 933 tail_lsn = xfs_ail_min_lsn(mp->m_ail); 934 if (!tail_lsn) 935 tail_lsn = atomic64_read(&log->l_last_sync_lsn); 936 atomic64_set(&log->l_tail_lsn, tail_lsn); 937 return tail_lsn; 938 } 939 940 /* 941 * Return the space in the log between the tail and the head. The head 942 * is passed in the cycle/bytes formal parms. In the special case where 943 * the reserve head has wrapped passed the tail, this calculation is no 944 * longer valid. In this case, just return 0 which means there is no space 945 * in the log. This works for all places where this function is called 946 * with the reserve head. Of course, if the write head were to ever 947 * wrap the tail, we should blow up. Rather than catch this case here, 948 * we depend on other ASSERTions in other parts of the code. XXXmiken 949 * 950 * This code also handles the case where the reservation head is behind 951 * the tail. The details of this case are described below, but the end 952 * result is that we return the size of the log as the amount of space left. 953 */ 954 STATIC int 955 xlog_space_left( 956 struct log *log, 957 atomic64_t *head) 958 { 959 int free_bytes; 960 int tail_bytes; 961 int tail_cycle; 962 int head_cycle; 963 int head_bytes; 964 965 xlog_crack_grant_head(head, &head_cycle, &head_bytes); 966 xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_bytes); 967 tail_bytes = BBTOB(tail_bytes); 968 if (tail_cycle == head_cycle && head_bytes >= tail_bytes) 969 free_bytes = log->l_logsize - (head_bytes - tail_bytes); 970 else if (tail_cycle + 1 < head_cycle) 971 return 0; 972 else if (tail_cycle < head_cycle) { 973 ASSERT(tail_cycle == (head_cycle - 1)); 974 free_bytes = tail_bytes - head_bytes; 975 } else { 976 /* 977 * The reservation head is behind the tail. 978 * In this case we just want to return the size of the 979 * log as the amount of space left. 980 */ 981 xfs_alert(log->l_mp, 982 "xlog_space_left: head behind tail\n" 983 " tail_cycle = %d, tail_bytes = %d\n" 984 " GH cycle = %d, GH bytes = %d", 985 tail_cycle, tail_bytes, head_cycle, head_bytes); 986 ASSERT(0); 987 free_bytes = log->l_logsize; 988 } 989 return free_bytes; 990 } 991 992 993 /* 994 * Log function which is called when an io completes. 995 * 996 * The log manager needs its own routine, in order to control what 997 * happens with the buffer after the write completes. 998 */ 999 void 1000 xlog_iodone(xfs_buf_t *bp) 1001 { 1002 xlog_in_core_t *iclog = bp->b_fspriv; 1003 xlog_t *l = iclog->ic_log; 1004 int aborted = 0; 1005 1006 /* 1007 * Race to shutdown the filesystem if we see an error. 1008 */ 1009 if (XFS_TEST_ERROR((xfs_buf_geterror(bp)), l->l_mp, 1010 XFS_ERRTAG_IODONE_IOERR, XFS_RANDOM_IODONE_IOERR)) { 1011 xfs_buf_ioerror_alert(bp, __func__); 1012 xfs_buf_stale(bp); 1013 xfs_force_shutdown(l->l_mp, SHUTDOWN_LOG_IO_ERROR); 1014 /* 1015 * This flag will be propagated to the trans-committed 1016 * callback routines to let them know that the log-commit 1017 * didn't succeed. 1018 */ 1019 aborted = XFS_LI_ABORTED; 1020 } else if (iclog->ic_state & XLOG_STATE_IOERROR) { 1021 aborted = XFS_LI_ABORTED; 1022 } 1023 1024 /* log I/O is always issued ASYNC */ 1025 ASSERT(XFS_BUF_ISASYNC(bp)); 1026 xlog_state_done_syncing(iclog, aborted); 1027 /* 1028 * do not reference the buffer (bp) here as we could race 1029 * with it being freed after writing the unmount record to the 1030 * log. 1031 */ 1032 1033 } /* xlog_iodone */ 1034 1035 /* 1036 * Return size of each in-core log record buffer. 1037 * 1038 * All machines get 8 x 32kB buffers by default, unless tuned otherwise. 1039 * 1040 * If the filesystem blocksize is too large, we may need to choose a 1041 * larger size since the directory code currently logs entire blocks. 1042 */ 1043 1044 STATIC void 1045 xlog_get_iclog_buffer_size(xfs_mount_t *mp, 1046 xlog_t *log) 1047 { 1048 int size; 1049 int xhdrs; 1050 1051 if (mp->m_logbufs <= 0) 1052 log->l_iclog_bufs = XLOG_MAX_ICLOGS; 1053 else 1054 log->l_iclog_bufs = mp->m_logbufs; 1055 1056 /* 1057 * Buffer size passed in from mount system call. 1058 */ 1059 if (mp->m_logbsize > 0) { 1060 size = log->l_iclog_size = mp->m_logbsize; 1061 log->l_iclog_size_log = 0; 1062 while (size != 1) { 1063 log->l_iclog_size_log++; 1064 size >>= 1; 1065 } 1066 1067 if (xfs_sb_version_haslogv2(&mp->m_sb)) { 1068 /* # headers = size / 32k 1069 * one header holds cycles from 32k of data 1070 */ 1071 1072 xhdrs = mp->m_logbsize / XLOG_HEADER_CYCLE_SIZE; 1073 if (mp->m_logbsize % XLOG_HEADER_CYCLE_SIZE) 1074 xhdrs++; 1075 log->l_iclog_hsize = xhdrs << BBSHIFT; 1076 log->l_iclog_heads = xhdrs; 1077 } else { 1078 ASSERT(mp->m_logbsize <= XLOG_BIG_RECORD_BSIZE); 1079 log->l_iclog_hsize = BBSIZE; 1080 log->l_iclog_heads = 1; 1081 } 1082 goto done; 1083 } 1084 1085 /* All machines use 32kB buffers by default. */ 1086 log->l_iclog_size = XLOG_BIG_RECORD_BSIZE; 1087 log->l_iclog_size_log = XLOG_BIG_RECORD_BSHIFT; 1088 1089 /* the default log size is 16k or 32k which is one header sector */ 1090 log->l_iclog_hsize = BBSIZE; 1091 log->l_iclog_heads = 1; 1092 1093 done: 1094 /* are we being asked to make the sizes selected above visible? */ 1095 if (mp->m_logbufs == 0) 1096 mp->m_logbufs = log->l_iclog_bufs; 1097 if (mp->m_logbsize == 0) 1098 mp->m_logbsize = log->l_iclog_size; 1099 } /* xlog_get_iclog_buffer_size */ 1100 1101 1102 /* 1103 * This routine initializes some of the log structure for a given mount point. 1104 * Its primary purpose is to fill in enough, so recovery can occur. However, 1105 * some other stuff may be filled in too. 1106 */ 1107 STATIC xlog_t * 1108 xlog_alloc_log(xfs_mount_t *mp, 1109 xfs_buftarg_t *log_target, 1110 xfs_daddr_t blk_offset, 1111 int num_bblks) 1112 { 1113 xlog_t *log; 1114 xlog_rec_header_t *head; 1115 xlog_in_core_t **iclogp; 1116 xlog_in_core_t *iclog, *prev_iclog=NULL; 1117 xfs_buf_t *bp; 1118 int i; 1119 int error = ENOMEM; 1120 uint log2_size = 0; 1121 1122 log = kmem_zalloc(sizeof(xlog_t), KM_MAYFAIL); 1123 if (!log) { 1124 xfs_warn(mp, "Log allocation failed: No memory!"); 1125 goto out; 1126 } 1127 1128 log->l_mp = mp; 1129 log->l_targ = log_target; 1130 log->l_logsize = BBTOB(num_bblks); 1131 log->l_logBBstart = blk_offset; 1132 log->l_logBBsize = num_bblks; 1133 log->l_covered_state = XLOG_STATE_COVER_IDLE; 1134 log->l_flags |= XLOG_ACTIVE_RECOVERY; 1135 1136 log->l_prev_block = -1; 1137 /* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */ 1138 xlog_assign_atomic_lsn(&log->l_tail_lsn, 1, 0); 1139 xlog_assign_atomic_lsn(&log->l_last_sync_lsn, 1, 0); 1140 log->l_curr_cycle = 1; /* 0 is bad since this is initial value */ 1141 1142 xlog_grant_head_init(&log->l_reserve_head); 1143 xlog_grant_head_init(&log->l_write_head); 1144 1145 error = EFSCORRUPTED; 1146 if (xfs_sb_version_hassector(&mp->m_sb)) { 1147 log2_size = mp->m_sb.sb_logsectlog; 1148 if (log2_size < BBSHIFT) { 1149 xfs_warn(mp, "Log sector size too small (0x%x < 0x%x)", 1150 log2_size, BBSHIFT); 1151 goto out_free_log; 1152 } 1153 1154 log2_size -= BBSHIFT; 1155 if (log2_size > mp->m_sectbb_log) { 1156 xfs_warn(mp, "Log sector size too large (0x%x > 0x%x)", 1157 log2_size, mp->m_sectbb_log); 1158 goto out_free_log; 1159 } 1160 1161 /* for larger sector sizes, must have v2 or external log */ 1162 if (log2_size && log->l_logBBstart > 0 && 1163 !xfs_sb_version_haslogv2(&mp->m_sb)) { 1164 xfs_warn(mp, 1165 "log sector size (0x%x) invalid for configuration.", 1166 log2_size); 1167 goto out_free_log; 1168 } 1169 } 1170 log->l_sectBBsize = 1 << log2_size; 1171 1172 xlog_get_iclog_buffer_size(mp, log); 1173 1174 error = ENOMEM; 1175 bp = xfs_buf_alloc(mp->m_logdev_targp, 0, log->l_iclog_size, 0); 1176 if (!bp) 1177 goto out_free_log; 1178 bp->b_iodone = xlog_iodone; 1179 ASSERT(xfs_buf_islocked(bp)); 1180 log->l_xbuf = bp; 1181 1182 spin_lock_init(&log->l_icloglock); 1183 init_waitqueue_head(&log->l_flush_wait); 1184 1185 /* log record size must be multiple of BBSIZE; see xlog_rec_header_t */ 1186 ASSERT((XFS_BUF_SIZE(bp) & BBMASK) == 0); 1187 1188 iclogp = &log->l_iclog; 1189 /* 1190 * The amount of memory to allocate for the iclog structure is 1191 * rather funky due to the way the structure is defined. It is 1192 * done this way so that we can use different sizes for machines 1193 * with different amounts of memory. See the definition of 1194 * xlog_in_core_t in xfs_log_priv.h for details. 1195 */ 1196 ASSERT(log->l_iclog_size >= 4096); 1197 for (i=0; i < log->l_iclog_bufs; i++) { 1198 *iclogp = kmem_zalloc(sizeof(xlog_in_core_t), KM_MAYFAIL); 1199 if (!*iclogp) 1200 goto out_free_iclog; 1201 1202 iclog = *iclogp; 1203 iclog->ic_prev = prev_iclog; 1204 prev_iclog = iclog; 1205 1206 bp = xfs_buf_get_uncached(mp->m_logdev_targp, 1207 log->l_iclog_size, 0); 1208 if (!bp) 1209 goto out_free_iclog; 1210 1211 bp->b_iodone = xlog_iodone; 1212 iclog->ic_bp = bp; 1213 iclog->ic_data = bp->b_addr; 1214 #ifdef DEBUG 1215 log->l_iclog_bak[i] = (xfs_caddr_t)&(iclog->ic_header); 1216 #endif 1217 head = &iclog->ic_header; 1218 memset(head, 0, sizeof(xlog_rec_header_t)); 1219 head->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM); 1220 head->h_version = cpu_to_be32( 1221 xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1); 1222 head->h_size = cpu_to_be32(log->l_iclog_size); 1223 /* new fields */ 1224 head->h_fmt = cpu_to_be32(XLOG_FMT); 1225 memcpy(&head->h_fs_uuid, &mp->m_sb.sb_uuid, sizeof(uuid_t)); 1226 1227 iclog->ic_size = XFS_BUF_SIZE(bp) - log->l_iclog_hsize; 1228 iclog->ic_state = XLOG_STATE_ACTIVE; 1229 iclog->ic_log = log; 1230 atomic_set(&iclog->ic_refcnt, 0); 1231 spin_lock_init(&iclog->ic_callback_lock); 1232 iclog->ic_callback_tail = &(iclog->ic_callback); 1233 iclog->ic_datap = (char *)iclog->ic_data + log->l_iclog_hsize; 1234 1235 ASSERT(xfs_buf_islocked(iclog->ic_bp)); 1236 init_waitqueue_head(&iclog->ic_force_wait); 1237 init_waitqueue_head(&iclog->ic_write_wait); 1238 1239 iclogp = &iclog->ic_next; 1240 } 1241 *iclogp = log->l_iclog; /* complete ring */ 1242 log->l_iclog->ic_prev = prev_iclog; /* re-write 1st prev ptr */ 1243 1244 error = xlog_cil_init(log); 1245 if (error) 1246 goto out_free_iclog; 1247 return log; 1248 1249 out_free_iclog: 1250 for (iclog = log->l_iclog; iclog; iclog = prev_iclog) { 1251 prev_iclog = iclog->ic_next; 1252 if (iclog->ic_bp) 1253 xfs_buf_free(iclog->ic_bp); 1254 kmem_free(iclog); 1255 } 1256 spinlock_destroy(&log->l_icloglock); 1257 xfs_buf_free(log->l_xbuf); 1258 out_free_log: 1259 kmem_free(log); 1260 out: 1261 return ERR_PTR(-error); 1262 } /* xlog_alloc_log */ 1263 1264 1265 /* 1266 * Write out the commit record of a transaction associated with the given 1267 * ticket. Return the lsn of the commit record. 1268 */ 1269 STATIC int 1270 xlog_commit_record( 1271 struct log *log, 1272 struct xlog_ticket *ticket, 1273 struct xlog_in_core **iclog, 1274 xfs_lsn_t *commitlsnp) 1275 { 1276 struct xfs_mount *mp = log->l_mp; 1277 int error; 1278 struct xfs_log_iovec reg = { 1279 .i_addr = NULL, 1280 .i_len = 0, 1281 .i_type = XLOG_REG_TYPE_COMMIT, 1282 }; 1283 struct xfs_log_vec vec = { 1284 .lv_niovecs = 1, 1285 .lv_iovecp = ®, 1286 }; 1287 1288 ASSERT_ALWAYS(iclog); 1289 error = xlog_write(log, &vec, ticket, commitlsnp, iclog, 1290 XLOG_COMMIT_TRANS); 1291 if (error) 1292 xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR); 1293 return error; 1294 } 1295 1296 /* 1297 * Push on the buffer cache code if we ever use more than 75% of the on-disk 1298 * log space. This code pushes on the lsn which would supposedly free up 1299 * the 25% which we want to leave free. We may need to adopt a policy which 1300 * pushes on an lsn which is further along in the log once we reach the high 1301 * water mark. In this manner, we would be creating a low water mark. 1302 */ 1303 STATIC void 1304 xlog_grant_push_ail( 1305 struct log *log, 1306 int need_bytes) 1307 { 1308 xfs_lsn_t threshold_lsn = 0; 1309 xfs_lsn_t last_sync_lsn; 1310 int free_blocks; 1311 int free_bytes; 1312 int threshold_block; 1313 int threshold_cycle; 1314 int free_threshold; 1315 1316 ASSERT(BTOBB(need_bytes) < log->l_logBBsize); 1317 1318 free_bytes = xlog_space_left(log, &log->l_reserve_head.grant); 1319 free_blocks = BTOBBT(free_bytes); 1320 1321 /* 1322 * Set the threshold for the minimum number of free blocks in the 1323 * log to the maximum of what the caller needs, one quarter of the 1324 * log, and 256 blocks. 1325 */ 1326 free_threshold = BTOBB(need_bytes); 1327 free_threshold = MAX(free_threshold, (log->l_logBBsize >> 2)); 1328 free_threshold = MAX(free_threshold, 256); 1329 if (free_blocks >= free_threshold) 1330 return; 1331 1332 xlog_crack_atomic_lsn(&log->l_tail_lsn, &threshold_cycle, 1333 &threshold_block); 1334 threshold_block += free_threshold; 1335 if (threshold_block >= log->l_logBBsize) { 1336 threshold_block -= log->l_logBBsize; 1337 threshold_cycle += 1; 1338 } 1339 threshold_lsn = xlog_assign_lsn(threshold_cycle, 1340 threshold_block); 1341 /* 1342 * Don't pass in an lsn greater than the lsn of the last 1343 * log record known to be on disk. Use a snapshot of the last sync lsn 1344 * so that it doesn't change between the compare and the set. 1345 */ 1346 last_sync_lsn = atomic64_read(&log->l_last_sync_lsn); 1347 if (XFS_LSN_CMP(threshold_lsn, last_sync_lsn) > 0) 1348 threshold_lsn = last_sync_lsn; 1349 1350 /* 1351 * Get the transaction layer to kick the dirty buffers out to 1352 * disk asynchronously. No point in trying to do this if 1353 * the filesystem is shutting down. 1354 */ 1355 if (!XLOG_FORCED_SHUTDOWN(log)) 1356 xfs_ail_push(log->l_ailp, threshold_lsn); 1357 } 1358 1359 /* 1360 * The bdstrat callback function for log bufs. This gives us a central 1361 * place to trap bufs in case we get hit by a log I/O error and need to 1362 * shutdown. Actually, in practice, even when we didn't get a log error, 1363 * we transition the iclogs to IOERROR state *after* flushing all existing 1364 * iclogs to disk. This is because we don't want anymore new transactions to be 1365 * started or completed afterwards. 1366 */ 1367 STATIC int 1368 xlog_bdstrat( 1369 struct xfs_buf *bp) 1370 { 1371 struct xlog_in_core *iclog = bp->b_fspriv; 1372 1373 if (iclog->ic_state & XLOG_STATE_IOERROR) { 1374 xfs_buf_ioerror(bp, EIO); 1375 xfs_buf_stale(bp); 1376 xfs_buf_ioend(bp, 0); 1377 /* 1378 * It would seem logical to return EIO here, but we rely on 1379 * the log state machine to propagate I/O errors instead of 1380 * doing it here. 1381 */ 1382 return 0; 1383 } 1384 1385 xfs_buf_iorequest(bp); 1386 return 0; 1387 } 1388 1389 /* 1390 * Flush out the in-core log (iclog) to the on-disk log in an asynchronous 1391 * fashion. Previously, we should have moved the current iclog 1392 * ptr in the log to point to the next available iclog. This allows further 1393 * write to continue while this code syncs out an iclog ready to go. 1394 * Before an in-core log can be written out, the data section must be scanned 1395 * to save away the 1st word of each BBSIZE block into the header. We replace 1396 * it with the current cycle count. Each BBSIZE block is tagged with the 1397 * cycle count because there in an implicit assumption that drives will 1398 * guarantee that entire 512 byte blocks get written at once. In other words, 1399 * we can't have part of a 512 byte block written and part not written. By 1400 * tagging each block, we will know which blocks are valid when recovering 1401 * after an unclean shutdown. 1402 * 1403 * This routine is single threaded on the iclog. No other thread can be in 1404 * this routine with the same iclog. Changing contents of iclog can there- 1405 * fore be done without grabbing the state machine lock. Updating the global 1406 * log will require grabbing the lock though. 1407 * 1408 * The entire log manager uses a logical block numbering scheme. Only 1409 * log_sync (and then only bwrite()) know about the fact that the log may 1410 * not start with block zero on a given device. The log block start offset 1411 * is added immediately before calling bwrite(). 1412 */ 1413 1414 STATIC int 1415 xlog_sync(xlog_t *log, 1416 xlog_in_core_t *iclog) 1417 { 1418 xfs_caddr_t dptr; /* pointer to byte sized element */ 1419 xfs_buf_t *bp; 1420 int i; 1421 uint count; /* byte count of bwrite */ 1422 uint count_init; /* initial count before roundup */ 1423 int roundoff; /* roundoff to BB or stripe */ 1424 int split = 0; /* split write into two regions */ 1425 int error; 1426 int v2 = xfs_sb_version_haslogv2(&log->l_mp->m_sb); 1427 1428 XFS_STATS_INC(xs_log_writes); 1429 ASSERT(atomic_read(&iclog->ic_refcnt) == 0); 1430 1431 /* Add for LR header */ 1432 count_init = log->l_iclog_hsize + iclog->ic_offset; 1433 1434 /* Round out the log write size */ 1435 if (v2 && log->l_mp->m_sb.sb_logsunit > 1) { 1436 /* we have a v2 stripe unit to use */ 1437 count = XLOG_LSUNITTOB(log, XLOG_BTOLSUNIT(log, count_init)); 1438 } else { 1439 count = BBTOB(BTOBB(count_init)); 1440 } 1441 roundoff = count - count_init; 1442 ASSERT(roundoff >= 0); 1443 ASSERT((v2 && log->l_mp->m_sb.sb_logsunit > 1 && 1444 roundoff < log->l_mp->m_sb.sb_logsunit) 1445 || 1446 (log->l_mp->m_sb.sb_logsunit <= 1 && 1447 roundoff < BBTOB(1))); 1448 1449 /* move grant heads by roundoff in sync */ 1450 xlog_grant_add_space(log, &log->l_reserve_head.grant, roundoff); 1451 xlog_grant_add_space(log, &log->l_write_head.grant, roundoff); 1452 1453 /* put cycle number in every block */ 1454 xlog_pack_data(log, iclog, roundoff); 1455 1456 /* real byte length */ 1457 if (v2) { 1458 iclog->ic_header.h_len = 1459 cpu_to_be32(iclog->ic_offset + roundoff); 1460 } else { 1461 iclog->ic_header.h_len = 1462 cpu_to_be32(iclog->ic_offset); 1463 } 1464 1465 bp = iclog->ic_bp; 1466 XFS_BUF_SET_ADDR(bp, BLOCK_LSN(be64_to_cpu(iclog->ic_header.h_lsn))); 1467 1468 XFS_STATS_ADD(xs_log_blocks, BTOBB(count)); 1469 1470 /* Do we need to split this write into 2 parts? */ 1471 if (XFS_BUF_ADDR(bp) + BTOBB(count) > log->l_logBBsize) { 1472 split = count - (BBTOB(log->l_logBBsize - XFS_BUF_ADDR(bp))); 1473 count = BBTOB(log->l_logBBsize - XFS_BUF_ADDR(bp)); 1474 iclog->ic_bwritecnt = 2; /* split into 2 writes */ 1475 } else { 1476 iclog->ic_bwritecnt = 1; 1477 } 1478 XFS_BUF_SET_COUNT(bp, count); 1479 bp->b_fspriv = iclog; 1480 XFS_BUF_ZEROFLAGS(bp); 1481 XFS_BUF_ASYNC(bp); 1482 bp->b_flags |= XBF_SYNCIO; 1483 1484 if (log->l_mp->m_flags & XFS_MOUNT_BARRIER) { 1485 bp->b_flags |= XBF_FUA; 1486 1487 /* 1488 * Flush the data device before flushing the log to make 1489 * sure all meta data written back from the AIL actually made 1490 * it to disk before stamping the new log tail LSN into the 1491 * log buffer. For an external log we need to issue the 1492 * flush explicitly, and unfortunately synchronously here; 1493 * for an internal log we can simply use the block layer 1494 * state machine for preflushes. 1495 */ 1496 if (log->l_mp->m_logdev_targp != log->l_mp->m_ddev_targp) 1497 xfs_blkdev_issue_flush(log->l_mp->m_ddev_targp); 1498 else 1499 bp->b_flags |= XBF_FLUSH; 1500 } 1501 1502 ASSERT(XFS_BUF_ADDR(bp) <= log->l_logBBsize-1); 1503 ASSERT(XFS_BUF_ADDR(bp) + BTOBB(count) <= log->l_logBBsize); 1504 1505 xlog_verify_iclog(log, iclog, count, B_TRUE); 1506 1507 /* account for log which doesn't start at block #0 */ 1508 XFS_BUF_SET_ADDR(bp, XFS_BUF_ADDR(bp) + log->l_logBBstart); 1509 /* 1510 * Don't call xfs_bwrite here. We do log-syncs even when the filesystem 1511 * is shutting down. 1512 */ 1513 XFS_BUF_WRITE(bp); 1514 1515 error = xlog_bdstrat(bp); 1516 if (error) { 1517 xfs_buf_ioerror_alert(bp, "xlog_sync"); 1518 return error; 1519 } 1520 if (split) { 1521 bp = iclog->ic_log->l_xbuf; 1522 XFS_BUF_SET_ADDR(bp, 0); /* logical 0 */ 1523 xfs_buf_associate_memory(bp, 1524 (char *)&iclog->ic_header + count, split); 1525 bp->b_fspriv = iclog; 1526 XFS_BUF_ZEROFLAGS(bp); 1527 XFS_BUF_ASYNC(bp); 1528 bp->b_flags |= XBF_SYNCIO; 1529 if (log->l_mp->m_flags & XFS_MOUNT_BARRIER) 1530 bp->b_flags |= XBF_FUA; 1531 dptr = bp->b_addr; 1532 /* 1533 * Bump the cycle numbers at the start of each block 1534 * since this part of the buffer is at the start of 1535 * a new cycle. Watch out for the header magic number 1536 * case, though. 1537 */ 1538 for (i = 0; i < split; i += BBSIZE) { 1539 be32_add_cpu((__be32 *)dptr, 1); 1540 if (be32_to_cpu(*(__be32 *)dptr) == XLOG_HEADER_MAGIC_NUM) 1541 be32_add_cpu((__be32 *)dptr, 1); 1542 dptr += BBSIZE; 1543 } 1544 1545 ASSERT(XFS_BUF_ADDR(bp) <= log->l_logBBsize-1); 1546 ASSERT(XFS_BUF_ADDR(bp) + BTOBB(count) <= log->l_logBBsize); 1547 1548 /* account for internal log which doesn't start at block #0 */ 1549 XFS_BUF_SET_ADDR(bp, XFS_BUF_ADDR(bp) + log->l_logBBstart); 1550 XFS_BUF_WRITE(bp); 1551 error = xlog_bdstrat(bp); 1552 if (error) { 1553 xfs_buf_ioerror_alert(bp, "xlog_sync (split)"); 1554 return error; 1555 } 1556 } 1557 return 0; 1558 } /* xlog_sync */ 1559 1560 1561 /* 1562 * Deallocate a log structure 1563 */ 1564 STATIC void 1565 xlog_dealloc_log(xlog_t *log) 1566 { 1567 xlog_in_core_t *iclog, *next_iclog; 1568 int i; 1569 1570 xlog_cil_destroy(log); 1571 1572 /* 1573 * always need to ensure that the extra buffer does not point to memory 1574 * owned by another log buffer before we free it. 1575 */ 1576 xfs_buf_set_empty(log->l_xbuf, log->l_iclog_size); 1577 xfs_buf_free(log->l_xbuf); 1578 1579 iclog = log->l_iclog; 1580 for (i=0; i<log->l_iclog_bufs; i++) { 1581 xfs_buf_free(iclog->ic_bp); 1582 next_iclog = iclog->ic_next; 1583 kmem_free(iclog); 1584 iclog = next_iclog; 1585 } 1586 spinlock_destroy(&log->l_icloglock); 1587 1588 log->l_mp->m_log = NULL; 1589 kmem_free(log); 1590 } /* xlog_dealloc_log */ 1591 1592 /* 1593 * Update counters atomically now that memcpy is done. 1594 */ 1595 /* ARGSUSED */ 1596 static inline void 1597 xlog_state_finish_copy(xlog_t *log, 1598 xlog_in_core_t *iclog, 1599 int record_cnt, 1600 int copy_bytes) 1601 { 1602 spin_lock(&log->l_icloglock); 1603 1604 be32_add_cpu(&iclog->ic_header.h_num_logops, record_cnt); 1605 iclog->ic_offset += copy_bytes; 1606 1607 spin_unlock(&log->l_icloglock); 1608 } /* xlog_state_finish_copy */ 1609 1610 1611 1612 1613 /* 1614 * print out info relating to regions written which consume 1615 * the reservation 1616 */ 1617 void 1618 xlog_print_tic_res( 1619 struct xfs_mount *mp, 1620 struct xlog_ticket *ticket) 1621 { 1622 uint i; 1623 uint ophdr_spc = ticket->t_res_num_ophdrs * (uint)sizeof(xlog_op_header_t); 1624 1625 /* match with XLOG_REG_TYPE_* in xfs_log.h */ 1626 static char *res_type_str[XLOG_REG_TYPE_MAX] = { 1627 "bformat", 1628 "bchunk", 1629 "efi_format", 1630 "efd_format", 1631 "iformat", 1632 "icore", 1633 "iext", 1634 "ibroot", 1635 "ilocal", 1636 "iattr_ext", 1637 "iattr_broot", 1638 "iattr_local", 1639 "qformat", 1640 "dquot", 1641 "quotaoff", 1642 "LR header", 1643 "unmount", 1644 "commit", 1645 "trans header" 1646 }; 1647 static char *trans_type_str[XFS_TRANS_TYPE_MAX] = { 1648 "SETATTR_NOT_SIZE", 1649 "SETATTR_SIZE", 1650 "INACTIVE", 1651 "CREATE", 1652 "CREATE_TRUNC", 1653 "TRUNCATE_FILE", 1654 "REMOVE", 1655 "LINK", 1656 "RENAME", 1657 "MKDIR", 1658 "RMDIR", 1659 "SYMLINK", 1660 "SET_DMATTRS", 1661 "GROWFS", 1662 "STRAT_WRITE", 1663 "DIOSTRAT", 1664 "WRITE_SYNC", 1665 "WRITEID", 1666 "ADDAFORK", 1667 "ATTRINVAL", 1668 "ATRUNCATE", 1669 "ATTR_SET", 1670 "ATTR_RM", 1671 "ATTR_FLAG", 1672 "CLEAR_AGI_BUCKET", 1673 "QM_SBCHANGE", 1674 "DUMMY1", 1675 "DUMMY2", 1676 "QM_QUOTAOFF", 1677 "QM_DQALLOC", 1678 "QM_SETQLIM", 1679 "QM_DQCLUSTER", 1680 "QM_QINOCREATE", 1681 "QM_QUOTAOFF_END", 1682 "SB_UNIT", 1683 "FSYNC_TS", 1684 "GROWFSRT_ALLOC", 1685 "GROWFSRT_ZERO", 1686 "GROWFSRT_FREE", 1687 "SWAPEXT" 1688 }; 1689 1690 xfs_warn(mp, 1691 "xlog_write: reservation summary:\n" 1692 " trans type = %s (%u)\n" 1693 " unit res = %d bytes\n" 1694 " current res = %d bytes\n" 1695 " total reg = %u bytes (o/flow = %u bytes)\n" 1696 " ophdrs = %u (ophdr space = %u bytes)\n" 1697 " ophdr + reg = %u bytes\n" 1698 " num regions = %u\n", 1699 ((ticket->t_trans_type <= 0 || 1700 ticket->t_trans_type > XFS_TRANS_TYPE_MAX) ? 1701 "bad-trans-type" : trans_type_str[ticket->t_trans_type-1]), 1702 ticket->t_trans_type, 1703 ticket->t_unit_res, 1704 ticket->t_curr_res, 1705 ticket->t_res_arr_sum, ticket->t_res_o_flow, 1706 ticket->t_res_num_ophdrs, ophdr_spc, 1707 ticket->t_res_arr_sum + 1708 ticket->t_res_o_flow + ophdr_spc, 1709 ticket->t_res_num); 1710 1711 for (i = 0; i < ticket->t_res_num; i++) { 1712 uint r_type = ticket->t_res_arr[i].r_type; 1713 xfs_warn(mp, "region[%u]: %s - %u bytes\n", i, 1714 ((r_type <= 0 || r_type > XLOG_REG_TYPE_MAX) ? 1715 "bad-rtype" : res_type_str[r_type-1]), 1716 ticket->t_res_arr[i].r_len); 1717 } 1718 1719 xfs_alert_tag(mp, XFS_PTAG_LOGRES, 1720 "xlog_write: reservation ran out. Need to up reservation"); 1721 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); 1722 } 1723 1724 /* 1725 * Calculate the potential space needed by the log vector. Each region gets 1726 * its own xlog_op_header_t and may need to be double word aligned. 1727 */ 1728 static int 1729 xlog_write_calc_vec_length( 1730 struct xlog_ticket *ticket, 1731 struct xfs_log_vec *log_vector) 1732 { 1733 struct xfs_log_vec *lv; 1734 int headers = 0; 1735 int len = 0; 1736 int i; 1737 1738 /* acct for start rec of xact */ 1739 if (ticket->t_flags & XLOG_TIC_INITED) 1740 headers++; 1741 1742 for (lv = log_vector; lv; lv = lv->lv_next) { 1743 headers += lv->lv_niovecs; 1744 1745 for (i = 0; i < lv->lv_niovecs; i++) { 1746 struct xfs_log_iovec *vecp = &lv->lv_iovecp[i]; 1747 1748 len += vecp->i_len; 1749 xlog_tic_add_region(ticket, vecp->i_len, vecp->i_type); 1750 } 1751 } 1752 1753 ticket->t_res_num_ophdrs += headers; 1754 len += headers * sizeof(struct xlog_op_header); 1755 1756 return len; 1757 } 1758 1759 /* 1760 * If first write for transaction, insert start record We can't be trying to 1761 * commit if we are inited. We can't have any "partial_copy" if we are inited. 1762 */ 1763 static int 1764 xlog_write_start_rec( 1765 struct xlog_op_header *ophdr, 1766 struct xlog_ticket *ticket) 1767 { 1768 if (!(ticket->t_flags & XLOG_TIC_INITED)) 1769 return 0; 1770 1771 ophdr->oh_tid = cpu_to_be32(ticket->t_tid); 1772 ophdr->oh_clientid = ticket->t_clientid; 1773 ophdr->oh_len = 0; 1774 ophdr->oh_flags = XLOG_START_TRANS; 1775 ophdr->oh_res2 = 0; 1776 1777 ticket->t_flags &= ~XLOG_TIC_INITED; 1778 1779 return sizeof(struct xlog_op_header); 1780 } 1781 1782 static xlog_op_header_t * 1783 xlog_write_setup_ophdr( 1784 struct log *log, 1785 struct xlog_op_header *ophdr, 1786 struct xlog_ticket *ticket, 1787 uint flags) 1788 { 1789 ophdr->oh_tid = cpu_to_be32(ticket->t_tid); 1790 ophdr->oh_clientid = ticket->t_clientid; 1791 ophdr->oh_res2 = 0; 1792 1793 /* are we copying a commit or unmount record? */ 1794 ophdr->oh_flags = flags; 1795 1796 /* 1797 * We've seen logs corrupted with bad transaction client ids. This 1798 * makes sure that XFS doesn't generate them on. Turn this into an EIO 1799 * and shut down the filesystem. 1800 */ 1801 switch (ophdr->oh_clientid) { 1802 case XFS_TRANSACTION: 1803 case XFS_VOLUME: 1804 case XFS_LOG: 1805 break; 1806 default: 1807 xfs_warn(log->l_mp, 1808 "Bad XFS transaction clientid 0x%x in ticket 0x%p", 1809 ophdr->oh_clientid, ticket); 1810 return NULL; 1811 } 1812 1813 return ophdr; 1814 } 1815 1816 /* 1817 * Set up the parameters of the region copy into the log. This has 1818 * to handle region write split across multiple log buffers - this 1819 * state is kept external to this function so that this code can 1820 * can be written in an obvious, self documenting manner. 1821 */ 1822 static int 1823 xlog_write_setup_copy( 1824 struct xlog_ticket *ticket, 1825 struct xlog_op_header *ophdr, 1826 int space_available, 1827 int space_required, 1828 int *copy_off, 1829 int *copy_len, 1830 int *last_was_partial_copy, 1831 int *bytes_consumed) 1832 { 1833 int still_to_copy; 1834 1835 still_to_copy = space_required - *bytes_consumed; 1836 *copy_off = *bytes_consumed; 1837 1838 if (still_to_copy <= space_available) { 1839 /* write of region completes here */ 1840 *copy_len = still_to_copy; 1841 ophdr->oh_len = cpu_to_be32(*copy_len); 1842 if (*last_was_partial_copy) 1843 ophdr->oh_flags |= (XLOG_END_TRANS|XLOG_WAS_CONT_TRANS); 1844 *last_was_partial_copy = 0; 1845 *bytes_consumed = 0; 1846 return 0; 1847 } 1848 1849 /* partial write of region, needs extra log op header reservation */ 1850 *copy_len = space_available; 1851 ophdr->oh_len = cpu_to_be32(*copy_len); 1852 ophdr->oh_flags |= XLOG_CONTINUE_TRANS; 1853 if (*last_was_partial_copy) 1854 ophdr->oh_flags |= XLOG_WAS_CONT_TRANS; 1855 *bytes_consumed += *copy_len; 1856 (*last_was_partial_copy)++; 1857 1858 /* account for new log op header */ 1859 ticket->t_curr_res -= sizeof(struct xlog_op_header); 1860 ticket->t_res_num_ophdrs++; 1861 1862 return sizeof(struct xlog_op_header); 1863 } 1864 1865 static int 1866 xlog_write_copy_finish( 1867 struct log *log, 1868 struct xlog_in_core *iclog, 1869 uint flags, 1870 int *record_cnt, 1871 int *data_cnt, 1872 int *partial_copy, 1873 int *partial_copy_len, 1874 int log_offset, 1875 struct xlog_in_core **commit_iclog) 1876 { 1877 if (*partial_copy) { 1878 /* 1879 * This iclog has already been marked WANT_SYNC by 1880 * xlog_state_get_iclog_space. 1881 */ 1882 xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt); 1883 *record_cnt = 0; 1884 *data_cnt = 0; 1885 return xlog_state_release_iclog(log, iclog); 1886 } 1887 1888 *partial_copy = 0; 1889 *partial_copy_len = 0; 1890 1891 if (iclog->ic_size - log_offset <= sizeof(xlog_op_header_t)) { 1892 /* no more space in this iclog - push it. */ 1893 xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt); 1894 *record_cnt = 0; 1895 *data_cnt = 0; 1896 1897 spin_lock(&log->l_icloglock); 1898 xlog_state_want_sync(log, iclog); 1899 spin_unlock(&log->l_icloglock); 1900 1901 if (!commit_iclog) 1902 return xlog_state_release_iclog(log, iclog); 1903 ASSERT(flags & XLOG_COMMIT_TRANS); 1904 *commit_iclog = iclog; 1905 } 1906 1907 return 0; 1908 } 1909 1910 /* 1911 * Write some region out to in-core log 1912 * 1913 * This will be called when writing externally provided regions or when 1914 * writing out a commit record for a given transaction. 1915 * 1916 * General algorithm: 1917 * 1. Find total length of this write. This may include adding to the 1918 * lengths passed in. 1919 * 2. Check whether we violate the tickets reservation. 1920 * 3. While writing to this iclog 1921 * A. Reserve as much space in this iclog as can get 1922 * B. If this is first write, save away start lsn 1923 * C. While writing this region: 1924 * 1. If first write of transaction, write start record 1925 * 2. Write log operation header (header per region) 1926 * 3. Find out if we can fit entire region into this iclog 1927 * 4. Potentially, verify destination memcpy ptr 1928 * 5. Memcpy (partial) region 1929 * 6. If partial copy, release iclog; otherwise, continue 1930 * copying more regions into current iclog 1931 * 4. Mark want sync bit (in simulation mode) 1932 * 5. Release iclog for potential flush to on-disk log. 1933 * 1934 * ERRORS: 1935 * 1. Panic if reservation is overrun. This should never happen since 1936 * reservation amounts are generated internal to the filesystem. 1937 * NOTES: 1938 * 1. Tickets are single threaded data structures. 1939 * 2. The XLOG_END_TRANS & XLOG_CONTINUE_TRANS flags are passed down to the 1940 * syncing routine. When a single log_write region needs to span 1941 * multiple in-core logs, the XLOG_CONTINUE_TRANS bit should be set 1942 * on all log operation writes which don't contain the end of the 1943 * region. The XLOG_END_TRANS bit is used for the in-core log 1944 * operation which contains the end of the continued log_write region. 1945 * 3. When xlog_state_get_iclog_space() grabs the rest of the current iclog, 1946 * we don't really know exactly how much space will be used. As a result, 1947 * we don't update ic_offset until the end when we know exactly how many 1948 * bytes have been written out. 1949 */ 1950 int 1951 xlog_write( 1952 struct log *log, 1953 struct xfs_log_vec *log_vector, 1954 struct xlog_ticket *ticket, 1955 xfs_lsn_t *start_lsn, 1956 struct xlog_in_core **commit_iclog, 1957 uint flags) 1958 { 1959 struct xlog_in_core *iclog = NULL; 1960 struct xfs_log_iovec *vecp; 1961 struct xfs_log_vec *lv; 1962 int len; 1963 int index; 1964 int partial_copy = 0; 1965 int partial_copy_len = 0; 1966 int contwr = 0; 1967 int record_cnt = 0; 1968 int data_cnt = 0; 1969 int error; 1970 1971 *start_lsn = 0; 1972 1973 len = xlog_write_calc_vec_length(ticket, log_vector); 1974 1975 /* 1976 * Region headers and bytes are already accounted for. 1977 * We only need to take into account start records and 1978 * split regions in this function. 1979 */ 1980 if (ticket->t_flags & XLOG_TIC_INITED) 1981 ticket->t_curr_res -= sizeof(xlog_op_header_t); 1982 1983 /* 1984 * Commit record headers need to be accounted for. These 1985 * come in as separate writes so are easy to detect. 1986 */ 1987 if (flags & (XLOG_COMMIT_TRANS | XLOG_UNMOUNT_TRANS)) 1988 ticket->t_curr_res -= sizeof(xlog_op_header_t); 1989 1990 if (ticket->t_curr_res < 0) 1991 xlog_print_tic_res(log->l_mp, ticket); 1992 1993 index = 0; 1994 lv = log_vector; 1995 vecp = lv->lv_iovecp; 1996 while (lv && index < lv->lv_niovecs) { 1997 void *ptr; 1998 int log_offset; 1999 2000 error = xlog_state_get_iclog_space(log, len, &iclog, ticket, 2001 &contwr, &log_offset); 2002 if (error) 2003 return error; 2004 2005 ASSERT(log_offset <= iclog->ic_size - 1); 2006 ptr = iclog->ic_datap + log_offset; 2007 2008 /* start_lsn is the first lsn written to. That's all we need. */ 2009 if (!*start_lsn) 2010 *start_lsn = be64_to_cpu(iclog->ic_header.h_lsn); 2011 2012 /* 2013 * This loop writes out as many regions as can fit in the amount 2014 * of space which was allocated by xlog_state_get_iclog_space(). 2015 */ 2016 while (lv && index < lv->lv_niovecs) { 2017 struct xfs_log_iovec *reg = &vecp[index]; 2018 struct xlog_op_header *ophdr; 2019 int start_rec_copy; 2020 int copy_len; 2021 int copy_off; 2022 2023 ASSERT(reg->i_len % sizeof(__int32_t) == 0); 2024 ASSERT((unsigned long)ptr % sizeof(__int32_t) == 0); 2025 2026 start_rec_copy = xlog_write_start_rec(ptr, ticket); 2027 if (start_rec_copy) { 2028 record_cnt++; 2029 xlog_write_adv_cnt(&ptr, &len, &log_offset, 2030 start_rec_copy); 2031 } 2032 2033 ophdr = xlog_write_setup_ophdr(log, ptr, ticket, flags); 2034 if (!ophdr) 2035 return XFS_ERROR(EIO); 2036 2037 xlog_write_adv_cnt(&ptr, &len, &log_offset, 2038 sizeof(struct xlog_op_header)); 2039 2040 len += xlog_write_setup_copy(ticket, ophdr, 2041 iclog->ic_size-log_offset, 2042 reg->i_len, 2043 ©_off, ©_len, 2044 &partial_copy, 2045 &partial_copy_len); 2046 xlog_verify_dest_ptr(log, ptr); 2047 2048 /* copy region */ 2049 ASSERT(copy_len >= 0); 2050 memcpy(ptr, reg->i_addr + copy_off, copy_len); 2051 xlog_write_adv_cnt(&ptr, &len, &log_offset, copy_len); 2052 2053 copy_len += start_rec_copy + sizeof(xlog_op_header_t); 2054 record_cnt++; 2055 data_cnt += contwr ? copy_len : 0; 2056 2057 error = xlog_write_copy_finish(log, iclog, flags, 2058 &record_cnt, &data_cnt, 2059 &partial_copy, 2060 &partial_copy_len, 2061 log_offset, 2062 commit_iclog); 2063 if (error) 2064 return error; 2065 2066 /* 2067 * if we had a partial copy, we need to get more iclog 2068 * space but we don't want to increment the region 2069 * index because there is still more is this region to 2070 * write. 2071 * 2072 * If we completed writing this region, and we flushed 2073 * the iclog (indicated by resetting of the record 2074 * count), then we also need to get more log space. If 2075 * this was the last record, though, we are done and 2076 * can just return. 2077 */ 2078 if (partial_copy) 2079 break; 2080 2081 if (++index == lv->lv_niovecs) { 2082 lv = lv->lv_next; 2083 index = 0; 2084 if (lv) 2085 vecp = lv->lv_iovecp; 2086 } 2087 if (record_cnt == 0) { 2088 if (!lv) 2089 return 0; 2090 break; 2091 } 2092 } 2093 } 2094 2095 ASSERT(len == 0); 2096 2097 xlog_state_finish_copy(log, iclog, record_cnt, data_cnt); 2098 if (!commit_iclog) 2099 return xlog_state_release_iclog(log, iclog); 2100 2101 ASSERT(flags & XLOG_COMMIT_TRANS); 2102 *commit_iclog = iclog; 2103 return 0; 2104 } 2105 2106 2107 /***************************************************************************** 2108 * 2109 * State Machine functions 2110 * 2111 ***************************************************************************** 2112 */ 2113 2114 /* Clean iclogs starting from the head. This ordering must be 2115 * maintained, so an iclog doesn't become ACTIVE beyond one that 2116 * is SYNCING. This is also required to maintain the notion that we use 2117 * a ordered wait queue to hold off would be writers to the log when every 2118 * iclog is trying to sync to disk. 2119 * 2120 * State Change: DIRTY -> ACTIVE 2121 */ 2122 STATIC void 2123 xlog_state_clean_log(xlog_t *log) 2124 { 2125 xlog_in_core_t *iclog; 2126 int changed = 0; 2127 2128 iclog = log->l_iclog; 2129 do { 2130 if (iclog->ic_state == XLOG_STATE_DIRTY) { 2131 iclog->ic_state = XLOG_STATE_ACTIVE; 2132 iclog->ic_offset = 0; 2133 ASSERT(iclog->ic_callback == NULL); 2134 /* 2135 * If the number of ops in this iclog indicate it just 2136 * contains the dummy transaction, we can 2137 * change state into IDLE (the second time around). 2138 * Otherwise we should change the state into 2139 * NEED a dummy. 2140 * We don't need to cover the dummy. 2141 */ 2142 if (!changed && 2143 (be32_to_cpu(iclog->ic_header.h_num_logops) == 2144 XLOG_COVER_OPS)) { 2145 changed = 1; 2146 } else { 2147 /* 2148 * We have two dirty iclogs so start over 2149 * This could also be num of ops indicates 2150 * this is not the dummy going out. 2151 */ 2152 changed = 2; 2153 } 2154 iclog->ic_header.h_num_logops = 0; 2155 memset(iclog->ic_header.h_cycle_data, 0, 2156 sizeof(iclog->ic_header.h_cycle_data)); 2157 iclog->ic_header.h_lsn = 0; 2158 } else if (iclog->ic_state == XLOG_STATE_ACTIVE) 2159 /* do nothing */; 2160 else 2161 break; /* stop cleaning */ 2162 iclog = iclog->ic_next; 2163 } while (iclog != log->l_iclog); 2164 2165 /* log is locked when we are called */ 2166 /* 2167 * Change state for the dummy log recording. 2168 * We usually go to NEED. But we go to NEED2 if the changed indicates 2169 * we are done writing the dummy record. 2170 * If we are done with the second dummy recored (DONE2), then 2171 * we go to IDLE. 2172 */ 2173 if (changed) { 2174 switch (log->l_covered_state) { 2175 case XLOG_STATE_COVER_IDLE: 2176 case XLOG_STATE_COVER_NEED: 2177 case XLOG_STATE_COVER_NEED2: 2178 log->l_covered_state = XLOG_STATE_COVER_NEED; 2179 break; 2180 2181 case XLOG_STATE_COVER_DONE: 2182 if (changed == 1) 2183 log->l_covered_state = XLOG_STATE_COVER_NEED2; 2184 else 2185 log->l_covered_state = XLOG_STATE_COVER_NEED; 2186 break; 2187 2188 case XLOG_STATE_COVER_DONE2: 2189 if (changed == 1) 2190 log->l_covered_state = XLOG_STATE_COVER_IDLE; 2191 else 2192 log->l_covered_state = XLOG_STATE_COVER_NEED; 2193 break; 2194 2195 default: 2196 ASSERT(0); 2197 } 2198 } 2199 } /* xlog_state_clean_log */ 2200 2201 STATIC xfs_lsn_t 2202 xlog_get_lowest_lsn( 2203 xlog_t *log) 2204 { 2205 xlog_in_core_t *lsn_log; 2206 xfs_lsn_t lowest_lsn, lsn; 2207 2208 lsn_log = log->l_iclog; 2209 lowest_lsn = 0; 2210 do { 2211 if (!(lsn_log->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_DIRTY))) { 2212 lsn = be64_to_cpu(lsn_log->ic_header.h_lsn); 2213 if ((lsn && !lowest_lsn) || 2214 (XFS_LSN_CMP(lsn, lowest_lsn) < 0)) { 2215 lowest_lsn = lsn; 2216 } 2217 } 2218 lsn_log = lsn_log->ic_next; 2219 } while (lsn_log != log->l_iclog); 2220 return lowest_lsn; 2221 } 2222 2223 2224 STATIC void 2225 xlog_state_do_callback( 2226 xlog_t *log, 2227 int aborted, 2228 xlog_in_core_t *ciclog) 2229 { 2230 xlog_in_core_t *iclog; 2231 xlog_in_core_t *first_iclog; /* used to know when we've 2232 * processed all iclogs once */ 2233 xfs_log_callback_t *cb, *cb_next; 2234 int flushcnt = 0; 2235 xfs_lsn_t lowest_lsn; 2236 int ioerrors; /* counter: iclogs with errors */ 2237 int loopdidcallbacks; /* flag: inner loop did callbacks*/ 2238 int funcdidcallbacks; /* flag: function did callbacks */ 2239 int repeats; /* for issuing console warnings if 2240 * looping too many times */ 2241 int wake = 0; 2242 2243 spin_lock(&log->l_icloglock); 2244 first_iclog = iclog = log->l_iclog; 2245 ioerrors = 0; 2246 funcdidcallbacks = 0; 2247 repeats = 0; 2248 2249 do { 2250 /* 2251 * Scan all iclogs starting with the one pointed to by the 2252 * log. Reset this starting point each time the log is 2253 * unlocked (during callbacks). 2254 * 2255 * Keep looping through iclogs until one full pass is made 2256 * without running any callbacks. 2257 */ 2258 first_iclog = log->l_iclog; 2259 iclog = log->l_iclog; 2260 loopdidcallbacks = 0; 2261 repeats++; 2262 2263 do { 2264 2265 /* skip all iclogs in the ACTIVE & DIRTY states */ 2266 if (iclog->ic_state & 2267 (XLOG_STATE_ACTIVE|XLOG_STATE_DIRTY)) { 2268 iclog = iclog->ic_next; 2269 continue; 2270 } 2271 2272 /* 2273 * Between marking a filesystem SHUTDOWN and stopping 2274 * the log, we do flush all iclogs to disk (if there 2275 * wasn't a log I/O error). So, we do want things to 2276 * go smoothly in case of just a SHUTDOWN w/o a 2277 * LOG_IO_ERROR. 2278 */ 2279 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) { 2280 /* 2281 * Can only perform callbacks in order. Since 2282 * this iclog is not in the DONE_SYNC/ 2283 * DO_CALLBACK state, we skip the rest and 2284 * just try to clean up. If we set our iclog 2285 * to DO_CALLBACK, we will not process it when 2286 * we retry since a previous iclog is in the 2287 * CALLBACK and the state cannot change since 2288 * we are holding the l_icloglock. 2289 */ 2290 if (!(iclog->ic_state & 2291 (XLOG_STATE_DONE_SYNC | 2292 XLOG_STATE_DO_CALLBACK))) { 2293 if (ciclog && (ciclog->ic_state == 2294 XLOG_STATE_DONE_SYNC)) { 2295 ciclog->ic_state = XLOG_STATE_DO_CALLBACK; 2296 } 2297 break; 2298 } 2299 /* 2300 * We now have an iclog that is in either the 2301 * DO_CALLBACK or DONE_SYNC states. The other 2302 * states (WANT_SYNC, SYNCING, or CALLBACK were 2303 * caught by the above if and are going to 2304 * clean (i.e. we aren't doing their callbacks) 2305 * see the above if. 2306 */ 2307 2308 /* 2309 * We will do one more check here to see if we 2310 * have chased our tail around. 2311 */ 2312 2313 lowest_lsn = xlog_get_lowest_lsn(log); 2314 if (lowest_lsn && 2315 XFS_LSN_CMP(lowest_lsn, 2316 be64_to_cpu(iclog->ic_header.h_lsn)) < 0) { 2317 iclog = iclog->ic_next; 2318 continue; /* Leave this iclog for 2319 * another thread */ 2320 } 2321 2322 iclog->ic_state = XLOG_STATE_CALLBACK; 2323 2324 2325 /* 2326 * update the last_sync_lsn before we drop the 2327 * icloglock to ensure we are the only one that 2328 * can update it. 2329 */ 2330 ASSERT(XFS_LSN_CMP(atomic64_read(&log->l_last_sync_lsn), 2331 be64_to_cpu(iclog->ic_header.h_lsn)) <= 0); 2332 atomic64_set(&log->l_last_sync_lsn, 2333 be64_to_cpu(iclog->ic_header.h_lsn)); 2334 2335 } else 2336 ioerrors++; 2337 2338 spin_unlock(&log->l_icloglock); 2339 2340 /* 2341 * Keep processing entries in the callback list until 2342 * we come around and it is empty. We need to 2343 * atomically see that the list is empty and change the 2344 * state to DIRTY so that we don't miss any more 2345 * callbacks being added. 2346 */ 2347 spin_lock(&iclog->ic_callback_lock); 2348 cb = iclog->ic_callback; 2349 while (cb) { 2350 iclog->ic_callback_tail = &(iclog->ic_callback); 2351 iclog->ic_callback = NULL; 2352 spin_unlock(&iclog->ic_callback_lock); 2353 2354 /* perform callbacks in the order given */ 2355 for (; cb; cb = cb_next) { 2356 cb_next = cb->cb_next; 2357 cb->cb_func(cb->cb_arg, aborted); 2358 } 2359 spin_lock(&iclog->ic_callback_lock); 2360 cb = iclog->ic_callback; 2361 } 2362 2363 loopdidcallbacks++; 2364 funcdidcallbacks++; 2365 2366 spin_lock(&log->l_icloglock); 2367 ASSERT(iclog->ic_callback == NULL); 2368 spin_unlock(&iclog->ic_callback_lock); 2369 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) 2370 iclog->ic_state = XLOG_STATE_DIRTY; 2371 2372 /* 2373 * Transition from DIRTY to ACTIVE if applicable. 2374 * NOP if STATE_IOERROR. 2375 */ 2376 xlog_state_clean_log(log); 2377 2378 /* wake up threads waiting in xfs_log_force() */ 2379 wake_up_all(&iclog->ic_force_wait); 2380 2381 iclog = iclog->ic_next; 2382 } while (first_iclog != iclog); 2383 2384 if (repeats > 5000) { 2385 flushcnt += repeats; 2386 repeats = 0; 2387 xfs_warn(log->l_mp, 2388 "%s: possible infinite loop (%d iterations)", 2389 __func__, flushcnt); 2390 } 2391 } while (!ioerrors && loopdidcallbacks); 2392 2393 /* 2394 * make one last gasp attempt to see if iclogs are being left in 2395 * limbo.. 2396 */ 2397 #ifdef DEBUG 2398 if (funcdidcallbacks) { 2399 first_iclog = iclog = log->l_iclog; 2400 do { 2401 ASSERT(iclog->ic_state != XLOG_STATE_DO_CALLBACK); 2402 /* 2403 * Terminate the loop if iclogs are found in states 2404 * which will cause other threads to clean up iclogs. 2405 * 2406 * SYNCING - i/o completion will go through logs 2407 * DONE_SYNC - interrupt thread should be waiting for 2408 * l_icloglock 2409 * IOERROR - give up hope all ye who enter here 2410 */ 2411 if (iclog->ic_state == XLOG_STATE_WANT_SYNC || 2412 iclog->ic_state == XLOG_STATE_SYNCING || 2413 iclog->ic_state == XLOG_STATE_DONE_SYNC || 2414 iclog->ic_state == XLOG_STATE_IOERROR ) 2415 break; 2416 iclog = iclog->ic_next; 2417 } while (first_iclog != iclog); 2418 } 2419 #endif 2420 2421 if (log->l_iclog->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_IOERROR)) 2422 wake = 1; 2423 spin_unlock(&log->l_icloglock); 2424 2425 if (wake) 2426 wake_up_all(&log->l_flush_wait); 2427 } 2428 2429 2430 /* 2431 * Finish transitioning this iclog to the dirty state. 2432 * 2433 * Make sure that we completely execute this routine only when this is 2434 * the last call to the iclog. There is a good chance that iclog flushes, 2435 * when we reach the end of the physical log, get turned into 2 separate 2436 * calls to bwrite. Hence, one iclog flush could generate two calls to this 2437 * routine. By using the reference count bwritecnt, we guarantee that only 2438 * the second completion goes through. 2439 * 2440 * Callbacks could take time, so they are done outside the scope of the 2441 * global state machine log lock. 2442 */ 2443 STATIC void 2444 xlog_state_done_syncing( 2445 xlog_in_core_t *iclog, 2446 int aborted) 2447 { 2448 xlog_t *log = iclog->ic_log; 2449 2450 spin_lock(&log->l_icloglock); 2451 2452 ASSERT(iclog->ic_state == XLOG_STATE_SYNCING || 2453 iclog->ic_state == XLOG_STATE_IOERROR); 2454 ASSERT(atomic_read(&iclog->ic_refcnt) == 0); 2455 ASSERT(iclog->ic_bwritecnt == 1 || iclog->ic_bwritecnt == 2); 2456 2457 2458 /* 2459 * If we got an error, either on the first buffer, or in the case of 2460 * split log writes, on the second, we mark ALL iclogs STATE_IOERROR, 2461 * and none should ever be attempted to be written to disk 2462 * again. 2463 */ 2464 if (iclog->ic_state != XLOG_STATE_IOERROR) { 2465 if (--iclog->ic_bwritecnt == 1) { 2466 spin_unlock(&log->l_icloglock); 2467 return; 2468 } 2469 iclog->ic_state = XLOG_STATE_DONE_SYNC; 2470 } 2471 2472 /* 2473 * Someone could be sleeping prior to writing out the next 2474 * iclog buffer, we wake them all, one will get to do the 2475 * I/O, the others get to wait for the result. 2476 */ 2477 wake_up_all(&iclog->ic_write_wait); 2478 spin_unlock(&log->l_icloglock); 2479 xlog_state_do_callback(log, aborted, iclog); /* also cleans log */ 2480 } /* xlog_state_done_syncing */ 2481 2482 2483 /* 2484 * If the head of the in-core log ring is not (ACTIVE or DIRTY), then we must 2485 * sleep. We wait on the flush queue on the head iclog as that should be 2486 * the first iclog to complete flushing. Hence if all iclogs are syncing, 2487 * we will wait here and all new writes will sleep until a sync completes. 2488 * 2489 * The in-core logs are used in a circular fashion. They are not used 2490 * out-of-order even when an iclog past the head is free. 2491 * 2492 * return: 2493 * * log_offset where xlog_write() can start writing into the in-core 2494 * log's data space. 2495 * * in-core log pointer to which xlog_write() should write. 2496 * * boolean indicating this is a continued write to an in-core log. 2497 * If this is the last write, then the in-core log's offset field 2498 * needs to be incremented, depending on the amount of data which 2499 * is copied. 2500 */ 2501 STATIC int 2502 xlog_state_get_iclog_space(xlog_t *log, 2503 int len, 2504 xlog_in_core_t **iclogp, 2505 xlog_ticket_t *ticket, 2506 int *continued_write, 2507 int *logoffsetp) 2508 { 2509 int log_offset; 2510 xlog_rec_header_t *head; 2511 xlog_in_core_t *iclog; 2512 int error; 2513 2514 restart: 2515 spin_lock(&log->l_icloglock); 2516 if (XLOG_FORCED_SHUTDOWN(log)) { 2517 spin_unlock(&log->l_icloglock); 2518 return XFS_ERROR(EIO); 2519 } 2520 2521 iclog = log->l_iclog; 2522 if (iclog->ic_state != XLOG_STATE_ACTIVE) { 2523 XFS_STATS_INC(xs_log_noiclogs); 2524 2525 /* Wait for log writes to have flushed */ 2526 xlog_wait(&log->l_flush_wait, &log->l_icloglock); 2527 goto restart; 2528 } 2529 2530 head = &iclog->ic_header; 2531 2532 atomic_inc(&iclog->ic_refcnt); /* prevents sync */ 2533 log_offset = iclog->ic_offset; 2534 2535 /* On the 1st write to an iclog, figure out lsn. This works 2536 * if iclogs marked XLOG_STATE_WANT_SYNC always write out what they are 2537 * committing to. If the offset is set, that's how many blocks 2538 * must be written. 2539 */ 2540 if (log_offset == 0) { 2541 ticket->t_curr_res -= log->l_iclog_hsize; 2542 xlog_tic_add_region(ticket, 2543 log->l_iclog_hsize, 2544 XLOG_REG_TYPE_LRHEADER); 2545 head->h_cycle = cpu_to_be32(log->l_curr_cycle); 2546 head->h_lsn = cpu_to_be64( 2547 xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block)); 2548 ASSERT(log->l_curr_block >= 0); 2549 } 2550 2551 /* If there is enough room to write everything, then do it. Otherwise, 2552 * claim the rest of the region and make sure the XLOG_STATE_WANT_SYNC 2553 * bit is on, so this will get flushed out. Don't update ic_offset 2554 * until you know exactly how many bytes get copied. Therefore, wait 2555 * until later to update ic_offset. 2556 * 2557 * xlog_write() algorithm assumes that at least 2 xlog_op_header_t's 2558 * can fit into remaining data section. 2559 */ 2560 if (iclog->ic_size - iclog->ic_offset < 2*sizeof(xlog_op_header_t)) { 2561 xlog_state_switch_iclogs(log, iclog, iclog->ic_size); 2562 2563 /* 2564 * If I'm the only one writing to this iclog, sync it to disk. 2565 * We need to do an atomic compare and decrement here to avoid 2566 * racing with concurrent atomic_dec_and_lock() calls in 2567 * xlog_state_release_iclog() when there is more than one 2568 * reference to the iclog. 2569 */ 2570 if (!atomic_add_unless(&iclog->ic_refcnt, -1, 1)) { 2571 /* we are the only one */ 2572 spin_unlock(&log->l_icloglock); 2573 error = xlog_state_release_iclog(log, iclog); 2574 if (error) 2575 return error; 2576 } else { 2577 spin_unlock(&log->l_icloglock); 2578 } 2579 goto restart; 2580 } 2581 2582 /* Do we have enough room to write the full amount in the remainder 2583 * of this iclog? Or must we continue a write on the next iclog and 2584 * mark this iclog as completely taken? In the case where we switch 2585 * iclogs (to mark it taken), this particular iclog will release/sync 2586 * to disk in xlog_write(). 2587 */ 2588 if (len <= iclog->ic_size - iclog->ic_offset) { 2589 *continued_write = 0; 2590 iclog->ic_offset += len; 2591 } else { 2592 *continued_write = 1; 2593 xlog_state_switch_iclogs(log, iclog, iclog->ic_size); 2594 } 2595 *iclogp = iclog; 2596 2597 ASSERT(iclog->ic_offset <= iclog->ic_size); 2598 spin_unlock(&log->l_icloglock); 2599 2600 *logoffsetp = log_offset; 2601 return 0; 2602 } /* xlog_state_get_iclog_space */ 2603 2604 /* The first cnt-1 times through here we don't need to 2605 * move the grant write head because the permanent 2606 * reservation has reserved cnt times the unit amount. 2607 * Release part of current permanent unit reservation and 2608 * reset current reservation to be one units worth. Also 2609 * move grant reservation head forward. 2610 */ 2611 STATIC void 2612 xlog_regrant_reserve_log_space(xlog_t *log, 2613 xlog_ticket_t *ticket) 2614 { 2615 trace_xfs_log_regrant_reserve_enter(log, ticket); 2616 2617 if (ticket->t_cnt > 0) 2618 ticket->t_cnt--; 2619 2620 xlog_grant_sub_space(log, &log->l_reserve_head.grant, 2621 ticket->t_curr_res); 2622 xlog_grant_sub_space(log, &log->l_write_head.grant, 2623 ticket->t_curr_res); 2624 ticket->t_curr_res = ticket->t_unit_res; 2625 xlog_tic_reset_res(ticket); 2626 2627 trace_xfs_log_regrant_reserve_sub(log, ticket); 2628 2629 /* just return if we still have some of the pre-reserved space */ 2630 if (ticket->t_cnt > 0) 2631 return; 2632 2633 xlog_grant_add_space(log, &log->l_reserve_head.grant, 2634 ticket->t_unit_res); 2635 2636 trace_xfs_log_regrant_reserve_exit(log, ticket); 2637 2638 ticket->t_curr_res = ticket->t_unit_res; 2639 xlog_tic_reset_res(ticket); 2640 } /* xlog_regrant_reserve_log_space */ 2641 2642 2643 /* 2644 * Give back the space left from a reservation. 2645 * 2646 * All the information we need to make a correct determination of space left 2647 * is present. For non-permanent reservations, things are quite easy. The 2648 * count should have been decremented to zero. We only need to deal with the 2649 * space remaining in the current reservation part of the ticket. If the 2650 * ticket contains a permanent reservation, there may be left over space which 2651 * needs to be released. A count of N means that N-1 refills of the current 2652 * reservation can be done before we need to ask for more space. The first 2653 * one goes to fill up the first current reservation. Once we run out of 2654 * space, the count will stay at zero and the only space remaining will be 2655 * in the current reservation field. 2656 */ 2657 STATIC void 2658 xlog_ungrant_log_space(xlog_t *log, 2659 xlog_ticket_t *ticket) 2660 { 2661 int bytes; 2662 2663 if (ticket->t_cnt > 0) 2664 ticket->t_cnt--; 2665 2666 trace_xfs_log_ungrant_enter(log, ticket); 2667 trace_xfs_log_ungrant_sub(log, ticket); 2668 2669 /* 2670 * If this is a permanent reservation ticket, we may be able to free 2671 * up more space based on the remaining count. 2672 */ 2673 bytes = ticket->t_curr_res; 2674 if (ticket->t_cnt > 0) { 2675 ASSERT(ticket->t_flags & XLOG_TIC_PERM_RESERV); 2676 bytes += ticket->t_unit_res*ticket->t_cnt; 2677 } 2678 2679 xlog_grant_sub_space(log, &log->l_reserve_head.grant, bytes); 2680 xlog_grant_sub_space(log, &log->l_write_head.grant, bytes); 2681 2682 trace_xfs_log_ungrant_exit(log, ticket); 2683 2684 xfs_log_space_wake(log->l_mp); 2685 } 2686 2687 /* 2688 * Flush iclog to disk if this is the last reference to the given iclog and 2689 * the WANT_SYNC bit is set. 2690 * 2691 * When this function is entered, the iclog is not necessarily in the 2692 * WANT_SYNC state. It may be sitting around waiting to get filled. 2693 * 2694 * 2695 */ 2696 STATIC int 2697 xlog_state_release_iclog( 2698 xlog_t *log, 2699 xlog_in_core_t *iclog) 2700 { 2701 int sync = 0; /* do we sync? */ 2702 2703 if (iclog->ic_state & XLOG_STATE_IOERROR) 2704 return XFS_ERROR(EIO); 2705 2706 ASSERT(atomic_read(&iclog->ic_refcnt) > 0); 2707 if (!atomic_dec_and_lock(&iclog->ic_refcnt, &log->l_icloglock)) 2708 return 0; 2709 2710 if (iclog->ic_state & XLOG_STATE_IOERROR) { 2711 spin_unlock(&log->l_icloglock); 2712 return XFS_ERROR(EIO); 2713 } 2714 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE || 2715 iclog->ic_state == XLOG_STATE_WANT_SYNC); 2716 2717 if (iclog->ic_state == XLOG_STATE_WANT_SYNC) { 2718 /* update tail before writing to iclog */ 2719 xfs_lsn_t tail_lsn = xlog_assign_tail_lsn(log->l_mp); 2720 sync++; 2721 iclog->ic_state = XLOG_STATE_SYNCING; 2722 iclog->ic_header.h_tail_lsn = cpu_to_be64(tail_lsn); 2723 xlog_verify_tail_lsn(log, iclog, tail_lsn); 2724 /* cycle incremented when incrementing curr_block */ 2725 } 2726 spin_unlock(&log->l_icloglock); 2727 2728 /* 2729 * We let the log lock go, so it's possible that we hit a log I/O 2730 * error or some other SHUTDOWN condition that marks the iclog 2731 * as XLOG_STATE_IOERROR before the bwrite. However, we know that 2732 * this iclog has consistent data, so we ignore IOERROR 2733 * flags after this point. 2734 */ 2735 if (sync) 2736 return xlog_sync(log, iclog); 2737 return 0; 2738 } /* xlog_state_release_iclog */ 2739 2740 2741 /* 2742 * This routine will mark the current iclog in the ring as WANT_SYNC 2743 * and move the current iclog pointer to the next iclog in the ring. 2744 * When this routine is called from xlog_state_get_iclog_space(), the 2745 * exact size of the iclog has not yet been determined. All we know is 2746 * that every data block. We have run out of space in this log record. 2747 */ 2748 STATIC void 2749 xlog_state_switch_iclogs(xlog_t *log, 2750 xlog_in_core_t *iclog, 2751 int eventual_size) 2752 { 2753 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE); 2754 if (!eventual_size) 2755 eventual_size = iclog->ic_offset; 2756 iclog->ic_state = XLOG_STATE_WANT_SYNC; 2757 iclog->ic_header.h_prev_block = cpu_to_be32(log->l_prev_block); 2758 log->l_prev_block = log->l_curr_block; 2759 log->l_prev_cycle = log->l_curr_cycle; 2760 2761 /* roll log?: ic_offset changed later */ 2762 log->l_curr_block += BTOBB(eventual_size)+BTOBB(log->l_iclog_hsize); 2763 2764 /* Round up to next log-sunit */ 2765 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb) && 2766 log->l_mp->m_sb.sb_logsunit > 1) { 2767 __uint32_t sunit_bb = BTOBB(log->l_mp->m_sb.sb_logsunit); 2768 log->l_curr_block = roundup(log->l_curr_block, sunit_bb); 2769 } 2770 2771 if (log->l_curr_block >= log->l_logBBsize) { 2772 log->l_curr_cycle++; 2773 if (log->l_curr_cycle == XLOG_HEADER_MAGIC_NUM) 2774 log->l_curr_cycle++; 2775 log->l_curr_block -= log->l_logBBsize; 2776 ASSERT(log->l_curr_block >= 0); 2777 } 2778 ASSERT(iclog == log->l_iclog); 2779 log->l_iclog = iclog->ic_next; 2780 } /* xlog_state_switch_iclogs */ 2781 2782 /* 2783 * Write out all data in the in-core log as of this exact moment in time. 2784 * 2785 * Data may be written to the in-core log during this call. However, 2786 * we don't guarantee this data will be written out. A change from past 2787 * implementation means this routine will *not* write out zero length LRs. 2788 * 2789 * Basically, we try and perform an intelligent scan of the in-core logs. 2790 * If we determine there is no flushable data, we just return. There is no 2791 * flushable data if: 2792 * 2793 * 1. the current iclog is active and has no data; the previous iclog 2794 * is in the active or dirty state. 2795 * 2. the current iclog is drity, and the previous iclog is in the 2796 * active or dirty state. 2797 * 2798 * We may sleep if: 2799 * 2800 * 1. the current iclog is not in the active nor dirty state. 2801 * 2. the current iclog dirty, and the previous iclog is not in the 2802 * active nor dirty state. 2803 * 3. the current iclog is active, and there is another thread writing 2804 * to this particular iclog. 2805 * 4. a) the current iclog is active and has no other writers 2806 * b) when we return from flushing out this iclog, it is still 2807 * not in the active nor dirty state. 2808 */ 2809 int 2810 _xfs_log_force( 2811 struct xfs_mount *mp, 2812 uint flags, 2813 int *log_flushed) 2814 { 2815 struct log *log = mp->m_log; 2816 struct xlog_in_core *iclog; 2817 xfs_lsn_t lsn; 2818 2819 XFS_STATS_INC(xs_log_force); 2820 2821 xlog_cil_force(log); 2822 2823 spin_lock(&log->l_icloglock); 2824 2825 iclog = log->l_iclog; 2826 if (iclog->ic_state & XLOG_STATE_IOERROR) { 2827 spin_unlock(&log->l_icloglock); 2828 return XFS_ERROR(EIO); 2829 } 2830 2831 /* If the head iclog is not active nor dirty, we just attach 2832 * ourselves to the head and go to sleep. 2833 */ 2834 if (iclog->ic_state == XLOG_STATE_ACTIVE || 2835 iclog->ic_state == XLOG_STATE_DIRTY) { 2836 /* 2837 * If the head is dirty or (active and empty), then 2838 * we need to look at the previous iclog. If the previous 2839 * iclog is active or dirty we are done. There is nothing 2840 * to sync out. Otherwise, we attach ourselves to the 2841 * previous iclog and go to sleep. 2842 */ 2843 if (iclog->ic_state == XLOG_STATE_DIRTY || 2844 (atomic_read(&iclog->ic_refcnt) == 0 2845 && iclog->ic_offset == 0)) { 2846 iclog = iclog->ic_prev; 2847 if (iclog->ic_state == XLOG_STATE_ACTIVE || 2848 iclog->ic_state == XLOG_STATE_DIRTY) 2849 goto no_sleep; 2850 else 2851 goto maybe_sleep; 2852 } else { 2853 if (atomic_read(&iclog->ic_refcnt) == 0) { 2854 /* We are the only one with access to this 2855 * iclog. Flush it out now. There should 2856 * be a roundoff of zero to show that someone 2857 * has already taken care of the roundoff from 2858 * the previous sync. 2859 */ 2860 atomic_inc(&iclog->ic_refcnt); 2861 lsn = be64_to_cpu(iclog->ic_header.h_lsn); 2862 xlog_state_switch_iclogs(log, iclog, 0); 2863 spin_unlock(&log->l_icloglock); 2864 2865 if (xlog_state_release_iclog(log, iclog)) 2866 return XFS_ERROR(EIO); 2867 2868 if (log_flushed) 2869 *log_flushed = 1; 2870 spin_lock(&log->l_icloglock); 2871 if (be64_to_cpu(iclog->ic_header.h_lsn) == lsn && 2872 iclog->ic_state != XLOG_STATE_DIRTY) 2873 goto maybe_sleep; 2874 else 2875 goto no_sleep; 2876 } else { 2877 /* Someone else is writing to this iclog. 2878 * Use its call to flush out the data. However, 2879 * the other thread may not force out this LR, 2880 * so we mark it WANT_SYNC. 2881 */ 2882 xlog_state_switch_iclogs(log, iclog, 0); 2883 goto maybe_sleep; 2884 } 2885 } 2886 } 2887 2888 /* By the time we come around again, the iclog could've been filled 2889 * which would give it another lsn. If we have a new lsn, just 2890 * return because the relevant data has been flushed. 2891 */ 2892 maybe_sleep: 2893 if (flags & XFS_LOG_SYNC) { 2894 /* 2895 * We must check if we're shutting down here, before 2896 * we wait, while we're holding the l_icloglock. 2897 * Then we check again after waking up, in case our 2898 * sleep was disturbed by a bad news. 2899 */ 2900 if (iclog->ic_state & XLOG_STATE_IOERROR) { 2901 spin_unlock(&log->l_icloglock); 2902 return XFS_ERROR(EIO); 2903 } 2904 XFS_STATS_INC(xs_log_force_sleep); 2905 xlog_wait(&iclog->ic_force_wait, &log->l_icloglock); 2906 /* 2907 * No need to grab the log lock here since we're 2908 * only deciding whether or not to return EIO 2909 * and the memory read should be atomic. 2910 */ 2911 if (iclog->ic_state & XLOG_STATE_IOERROR) 2912 return XFS_ERROR(EIO); 2913 if (log_flushed) 2914 *log_flushed = 1; 2915 } else { 2916 2917 no_sleep: 2918 spin_unlock(&log->l_icloglock); 2919 } 2920 return 0; 2921 } 2922 2923 /* 2924 * Wrapper for _xfs_log_force(), to be used when caller doesn't care 2925 * about errors or whether the log was flushed or not. This is the normal 2926 * interface to use when trying to unpin items or move the log forward. 2927 */ 2928 void 2929 xfs_log_force( 2930 xfs_mount_t *mp, 2931 uint flags) 2932 { 2933 int error; 2934 2935 error = _xfs_log_force(mp, flags, NULL); 2936 if (error) 2937 xfs_warn(mp, "%s: error %d returned.", __func__, error); 2938 } 2939 2940 /* 2941 * Force the in-core log to disk for a specific LSN. 2942 * 2943 * Find in-core log with lsn. 2944 * If it is in the DIRTY state, just return. 2945 * If it is in the ACTIVE state, move the in-core log into the WANT_SYNC 2946 * state and go to sleep or return. 2947 * If it is in any other state, go to sleep or return. 2948 * 2949 * Synchronous forces are implemented with a signal variable. All callers 2950 * to force a given lsn to disk will wait on a the sv attached to the 2951 * specific in-core log. When given in-core log finally completes its 2952 * write to disk, that thread will wake up all threads waiting on the 2953 * sv. 2954 */ 2955 int 2956 _xfs_log_force_lsn( 2957 struct xfs_mount *mp, 2958 xfs_lsn_t lsn, 2959 uint flags, 2960 int *log_flushed) 2961 { 2962 struct log *log = mp->m_log; 2963 struct xlog_in_core *iclog; 2964 int already_slept = 0; 2965 2966 ASSERT(lsn != 0); 2967 2968 XFS_STATS_INC(xs_log_force); 2969 2970 lsn = xlog_cil_force_lsn(log, lsn); 2971 if (lsn == NULLCOMMITLSN) 2972 return 0; 2973 2974 try_again: 2975 spin_lock(&log->l_icloglock); 2976 iclog = log->l_iclog; 2977 if (iclog->ic_state & XLOG_STATE_IOERROR) { 2978 spin_unlock(&log->l_icloglock); 2979 return XFS_ERROR(EIO); 2980 } 2981 2982 do { 2983 if (be64_to_cpu(iclog->ic_header.h_lsn) != lsn) { 2984 iclog = iclog->ic_next; 2985 continue; 2986 } 2987 2988 if (iclog->ic_state == XLOG_STATE_DIRTY) { 2989 spin_unlock(&log->l_icloglock); 2990 return 0; 2991 } 2992 2993 if (iclog->ic_state == XLOG_STATE_ACTIVE) { 2994 /* 2995 * We sleep here if we haven't already slept (e.g. 2996 * this is the first time we've looked at the correct 2997 * iclog buf) and the buffer before us is going to 2998 * be sync'ed. The reason for this is that if we 2999 * are doing sync transactions here, by waiting for 3000 * the previous I/O to complete, we can allow a few 3001 * more transactions into this iclog before we close 3002 * it down. 3003 * 3004 * Otherwise, we mark the buffer WANT_SYNC, and bump 3005 * up the refcnt so we can release the log (which 3006 * drops the ref count). The state switch keeps new 3007 * transaction commits from using this buffer. When 3008 * the current commits finish writing into the buffer, 3009 * the refcount will drop to zero and the buffer will 3010 * go out then. 3011 */ 3012 if (!already_slept && 3013 (iclog->ic_prev->ic_state & 3014 (XLOG_STATE_WANT_SYNC | XLOG_STATE_SYNCING))) { 3015 ASSERT(!(iclog->ic_state & XLOG_STATE_IOERROR)); 3016 3017 XFS_STATS_INC(xs_log_force_sleep); 3018 3019 xlog_wait(&iclog->ic_prev->ic_write_wait, 3020 &log->l_icloglock); 3021 if (log_flushed) 3022 *log_flushed = 1; 3023 already_slept = 1; 3024 goto try_again; 3025 } 3026 atomic_inc(&iclog->ic_refcnt); 3027 xlog_state_switch_iclogs(log, iclog, 0); 3028 spin_unlock(&log->l_icloglock); 3029 if (xlog_state_release_iclog(log, iclog)) 3030 return XFS_ERROR(EIO); 3031 if (log_flushed) 3032 *log_flushed = 1; 3033 spin_lock(&log->l_icloglock); 3034 } 3035 3036 if ((flags & XFS_LOG_SYNC) && /* sleep */ 3037 !(iclog->ic_state & 3038 (XLOG_STATE_ACTIVE | XLOG_STATE_DIRTY))) { 3039 /* 3040 * Don't wait on completion if we know that we've 3041 * gotten a log write error. 3042 */ 3043 if (iclog->ic_state & XLOG_STATE_IOERROR) { 3044 spin_unlock(&log->l_icloglock); 3045 return XFS_ERROR(EIO); 3046 } 3047 XFS_STATS_INC(xs_log_force_sleep); 3048 xlog_wait(&iclog->ic_force_wait, &log->l_icloglock); 3049 /* 3050 * No need to grab the log lock here since we're 3051 * only deciding whether or not to return EIO 3052 * and the memory read should be atomic. 3053 */ 3054 if (iclog->ic_state & XLOG_STATE_IOERROR) 3055 return XFS_ERROR(EIO); 3056 3057 if (log_flushed) 3058 *log_flushed = 1; 3059 } else { /* just return */ 3060 spin_unlock(&log->l_icloglock); 3061 } 3062 3063 return 0; 3064 } while (iclog != log->l_iclog); 3065 3066 spin_unlock(&log->l_icloglock); 3067 return 0; 3068 } 3069 3070 /* 3071 * Wrapper for _xfs_log_force_lsn(), to be used when caller doesn't care 3072 * about errors or whether the log was flushed or not. This is the normal 3073 * interface to use when trying to unpin items or move the log forward. 3074 */ 3075 void 3076 xfs_log_force_lsn( 3077 xfs_mount_t *mp, 3078 xfs_lsn_t lsn, 3079 uint flags) 3080 { 3081 int error; 3082 3083 error = _xfs_log_force_lsn(mp, lsn, flags, NULL); 3084 if (error) 3085 xfs_warn(mp, "%s: error %d returned.", __func__, error); 3086 } 3087 3088 /* 3089 * Called when we want to mark the current iclog as being ready to sync to 3090 * disk. 3091 */ 3092 STATIC void 3093 xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog) 3094 { 3095 assert_spin_locked(&log->l_icloglock); 3096 3097 if (iclog->ic_state == XLOG_STATE_ACTIVE) { 3098 xlog_state_switch_iclogs(log, iclog, 0); 3099 } else { 3100 ASSERT(iclog->ic_state & 3101 (XLOG_STATE_WANT_SYNC|XLOG_STATE_IOERROR)); 3102 } 3103 } 3104 3105 3106 /***************************************************************************** 3107 * 3108 * TICKET functions 3109 * 3110 ***************************************************************************** 3111 */ 3112 3113 /* 3114 * Free a used ticket when its refcount falls to zero. 3115 */ 3116 void 3117 xfs_log_ticket_put( 3118 xlog_ticket_t *ticket) 3119 { 3120 ASSERT(atomic_read(&ticket->t_ref) > 0); 3121 if (atomic_dec_and_test(&ticket->t_ref)) 3122 kmem_zone_free(xfs_log_ticket_zone, ticket); 3123 } 3124 3125 xlog_ticket_t * 3126 xfs_log_ticket_get( 3127 xlog_ticket_t *ticket) 3128 { 3129 ASSERT(atomic_read(&ticket->t_ref) > 0); 3130 atomic_inc(&ticket->t_ref); 3131 return ticket; 3132 } 3133 3134 /* 3135 * Allocate and initialise a new log ticket. 3136 */ 3137 xlog_ticket_t * 3138 xlog_ticket_alloc( 3139 struct log *log, 3140 int unit_bytes, 3141 int cnt, 3142 char client, 3143 bool permanent, 3144 int alloc_flags) 3145 { 3146 struct xlog_ticket *tic; 3147 uint num_headers; 3148 int iclog_space; 3149 3150 tic = kmem_zone_zalloc(xfs_log_ticket_zone, alloc_flags); 3151 if (!tic) 3152 return NULL; 3153 3154 /* 3155 * Permanent reservations have up to 'cnt'-1 active log operations 3156 * in the log. A unit in this case is the amount of space for one 3157 * of these log operations. Normal reservations have a cnt of 1 3158 * and their unit amount is the total amount of space required. 3159 * 3160 * The following lines of code account for non-transaction data 3161 * which occupy space in the on-disk log. 3162 * 3163 * Normal form of a transaction is: 3164 * <oph><trans-hdr><start-oph><reg1-oph><reg1><reg2-oph>...<commit-oph> 3165 * and then there are LR hdrs, split-recs and roundoff at end of syncs. 3166 * 3167 * We need to account for all the leadup data and trailer data 3168 * around the transaction data. 3169 * And then we need to account for the worst case in terms of using 3170 * more space. 3171 * The worst case will happen if: 3172 * - the placement of the transaction happens to be such that the 3173 * roundoff is at its maximum 3174 * - the transaction data is synced before the commit record is synced 3175 * i.e. <transaction-data><roundoff> | <commit-rec><roundoff> 3176 * Therefore the commit record is in its own Log Record. 3177 * This can happen as the commit record is called with its 3178 * own region to xlog_write(). 3179 * This then means that in the worst case, roundoff can happen for 3180 * the commit-rec as well. 3181 * The commit-rec is smaller than padding in this scenario and so it is 3182 * not added separately. 3183 */ 3184 3185 /* for trans header */ 3186 unit_bytes += sizeof(xlog_op_header_t); 3187 unit_bytes += sizeof(xfs_trans_header_t); 3188 3189 /* for start-rec */ 3190 unit_bytes += sizeof(xlog_op_header_t); 3191 3192 /* 3193 * for LR headers - the space for data in an iclog is the size minus 3194 * the space used for the headers. If we use the iclog size, then we 3195 * undercalculate the number of headers required. 3196 * 3197 * Furthermore - the addition of op headers for split-recs might 3198 * increase the space required enough to require more log and op 3199 * headers, so take that into account too. 3200 * 3201 * IMPORTANT: This reservation makes the assumption that if this 3202 * transaction is the first in an iclog and hence has the LR headers 3203 * accounted to it, then the remaining space in the iclog is 3204 * exclusively for this transaction. i.e. if the transaction is larger 3205 * than the iclog, it will be the only thing in that iclog. 3206 * Fundamentally, this means we must pass the entire log vector to 3207 * xlog_write to guarantee this. 3208 */ 3209 iclog_space = log->l_iclog_size - log->l_iclog_hsize; 3210 num_headers = howmany(unit_bytes, iclog_space); 3211 3212 /* for split-recs - ophdrs added when data split over LRs */ 3213 unit_bytes += sizeof(xlog_op_header_t) * num_headers; 3214 3215 /* add extra header reservations if we overrun */ 3216 while (!num_headers || 3217 howmany(unit_bytes, iclog_space) > num_headers) { 3218 unit_bytes += sizeof(xlog_op_header_t); 3219 num_headers++; 3220 } 3221 unit_bytes += log->l_iclog_hsize * num_headers; 3222 3223 /* for commit-rec LR header - note: padding will subsume the ophdr */ 3224 unit_bytes += log->l_iclog_hsize; 3225 3226 /* for roundoff padding for transaction data and one for commit record */ 3227 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb) && 3228 log->l_mp->m_sb.sb_logsunit > 1) { 3229 /* log su roundoff */ 3230 unit_bytes += 2*log->l_mp->m_sb.sb_logsunit; 3231 } else { 3232 /* BB roundoff */ 3233 unit_bytes += 2*BBSIZE; 3234 } 3235 3236 atomic_set(&tic->t_ref, 1); 3237 tic->t_task = current; 3238 INIT_LIST_HEAD(&tic->t_queue); 3239 tic->t_unit_res = unit_bytes; 3240 tic->t_curr_res = unit_bytes; 3241 tic->t_cnt = cnt; 3242 tic->t_ocnt = cnt; 3243 tic->t_tid = random32(); 3244 tic->t_clientid = client; 3245 tic->t_flags = XLOG_TIC_INITED; 3246 tic->t_trans_type = 0; 3247 if (permanent) 3248 tic->t_flags |= XLOG_TIC_PERM_RESERV; 3249 3250 xlog_tic_reset_res(tic); 3251 3252 return tic; 3253 } 3254 3255 3256 /****************************************************************************** 3257 * 3258 * Log debug routines 3259 * 3260 ****************************************************************************** 3261 */ 3262 #if defined(DEBUG) 3263 /* 3264 * Make sure that the destination ptr is within the valid data region of 3265 * one of the iclogs. This uses backup pointers stored in a different 3266 * part of the log in case we trash the log structure. 3267 */ 3268 void 3269 xlog_verify_dest_ptr( 3270 struct log *log, 3271 char *ptr) 3272 { 3273 int i; 3274 int good_ptr = 0; 3275 3276 for (i = 0; i < log->l_iclog_bufs; i++) { 3277 if (ptr >= log->l_iclog_bak[i] && 3278 ptr <= log->l_iclog_bak[i] + log->l_iclog_size) 3279 good_ptr++; 3280 } 3281 3282 if (!good_ptr) 3283 xfs_emerg(log->l_mp, "%s: invalid ptr", __func__); 3284 } 3285 3286 /* 3287 * Check to make sure the grant write head didn't just over lap the tail. If 3288 * the cycles are the same, we can't be overlapping. Otherwise, make sure that 3289 * the cycles differ by exactly one and check the byte count. 3290 * 3291 * This check is run unlocked, so can give false positives. Rather than assert 3292 * on failures, use a warn-once flag and a panic tag to allow the admin to 3293 * determine if they want to panic the machine when such an error occurs. For 3294 * debug kernels this will have the same effect as using an assert but, unlinke 3295 * an assert, it can be turned off at runtime. 3296 */ 3297 STATIC void 3298 xlog_verify_grant_tail( 3299 struct log *log) 3300 { 3301 int tail_cycle, tail_blocks; 3302 int cycle, space; 3303 3304 xlog_crack_grant_head(&log->l_write_head.grant, &cycle, &space); 3305 xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_blocks); 3306 if (tail_cycle != cycle) { 3307 if (cycle - 1 != tail_cycle && 3308 !(log->l_flags & XLOG_TAIL_WARN)) { 3309 xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES, 3310 "%s: cycle - 1 != tail_cycle", __func__); 3311 log->l_flags |= XLOG_TAIL_WARN; 3312 } 3313 3314 if (space > BBTOB(tail_blocks) && 3315 !(log->l_flags & XLOG_TAIL_WARN)) { 3316 xfs_alert_tag(log->l_mp, XFS_PTAG_LOGRES, 3317 "%s: space > BBTOB(tail_blocks)", __func__); 3318 log->l_flags |= XLOG_TAIL_WARN; 3319 } 3320 } 3321 } 3322 3323 /* check if it will fit */ 3324 STATIC void 3325 xlog_verify_tail_lsn(xlog_t *log, 3326 xlog_in_core_t *iclog, 3327 xfs_lsn_t tail_lsn) 3328 { 3329 int blocks; 3330 3331 if (CYCLE_LSN(tail_lsn) == log->l_prev_cycle) { 3332 blocks = 3333 log->l_logBBsize - (log->l_prev_block - BLOCK_LSN(tail_lsn)); 3334 if (blocks < BTOBB(iclog->ic_offset)+BTOBB(log->l_iclog_hsize)) 3335 xfs_emerg(log->l_mp, "%s: ran out of log space", __func__); 3336 } else { 3337 ASSERT(CYCLE_LSN(tail_lsn)+1 == log->l_prev_cycle); 3338 3339 if (BLOCK_LSN(tail_lsn) == log->l_prev_block) 3340 xfs_emerg(log->l_mp, "%s: tail wrapped", __func__); 3341 3342 blocks = BLOCK_LSN(tail_lsn) - log->l_prev_block; 3343 if (blocks < BTOBB(iclog->ic_offset) + 1) 3344 xfs_emerg(log->l_mp, "%s: ran out of log space", __func__); 3345 } 3346 } /* xlog_verify_tail_lsn */ 3347 3348 /* 3349 * Perform a number of checks on the iclog before writing to disk. 3350 * 3351 * 1. Make sure the iclogs are still circular 3352 * 2. Make sure we have a good magic number 3353 * 3. Make sure we don't have magic numbers in the data 3354 * 4. Check fields of each log operation header for: 3355 * A. Valid client identifier 3356 * B. tid ptr value falls in valid ptr space (user space code) 3357 * C. Length in log record header is correct according to the 3358 * individual operation headers within record. 3359 * 5. When a bwrite will occur within 5 blocks of the front of the physical 3360 * log, check the preceding blocks of the physical log to make sure all 3361 * the cycle numbers agree with the current cycle number. 3362 */ 3363 STATIC void 3364 xlog_verify_iclog(xlog_t *log, 3365 xlog_in_core_t *iclog, 3366 int count, 3367 boolean_t syncing) 3368 { 3369 xlog_op_header_t *ophead; 3370 xlog_in_core_t *icptr; 3371 xlog_in_core_2_t *xhdr; 3372 xfs_caddr_t ptr; 3373 xfs_caddr_t base_ptr; 3374 __psint_t field_offset; 3375 __uint8_t clientid; 3376 int len, i, j, k, op_len; 3377 int idx; 3378 3379 /* check validity of iclog pointers */ 3380 spin_lock(&log->l_icloglock); 3381 icptr = log->l_iclog; 3382 for (i=0; i < log->l_iclog_bufs; i++) { 3383 if (icptr == NULL) 3384 xfs_emerg(log->l_mp, "%s: invalid ptr", __func__); 3385 icptr = icptr->ic_next; 3386 } 3387 if (icptr != log->l_iclog) 3388 xfs_emerg(log->l_mp, "%s: corrupt iclog ring", __func__); 3389 spin_unlock(&log->l_icloglock); 3390 3391 /* check log magic numbers */ 3392 if (iclog->ic_header.h_magicno != cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) 3393 xfs_emerg(log->l_mp, "%s: invalid magic num", __func__); 3394 3395 ptr = (xfs_caddr_t) &iclog->ic_header; 3396 for (ptr += BBSIZE; ptr < ((xfs_caddr_t)&iclog->ic_header) + count; 3397 ptr += BBSIZE) { 3398 if (*(__be32 *)ptr == cpu_to_be32(XLOG_HEADER_MAGIC_NUM)) 3399 xfs_emerg(log->l_mp, "%s: unexpected magic num", 3400 __func__); 3401 } 3402 3403 /* check fields */ 3404 len = be32_to_cpu(iclog->ic_header.h_num_logops); 3405 ptr = iclog->ic_datap; 3406 base_ptr = ptr; 3407 ophead = (xlog_op_header_t *)ptr; 3408 xhdr = iclog->ic_data; 3409 for (i = 0; i < len; i++) { 3410 ophead = (xlog_op_header_t *)ptr; 3411 3412 /* clientid is only 1 byte */ 3413 field_offset = (__psint_t) 3414 ((xfs_caddr_t)&(ophead->oh_clientid) - base_ptr); 3415 if (syncing == B_FALSE || (field_offset & 0x1ff)) { 3416 clientid = ophead->oh_clientid; 3417 } else { 3418 idx = BTOBBT((xfs_caddr_t)&(ophead->oh_clientid) - iclog->ic_datap); 3419 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) { 3420 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3421 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3422 clientid = xlog_get_client_id( 3423 xhdr[j].hic_xheader.xh_cycle_data[k]); 3424 } else { 3425 clientid = xlog_get_client_id( 3426 iclog->ic_header.h_cycle_data[idx]); 3427 } 3428 } 3429 if (clientid != XFS_TRANSACTION && clientid != XFS_LOG) 3430 xfs_warn(log->l_mp, 3431 "%s: invalid clientid %d op 0x%p offset 0x%lx", 3432 __func__, clientid, ophead, 3433 (unsigned long)field_offset); 3434 3435 /* check length */ 3436 field_offset = (__psint_t) 3437 ((xfs_caddr_t)&(ophead->oh_len) - base_ptr); 3438 if (syncing == B_FALSE || (field_offset & 0x1ff)) { 3439 op_len = be32_to_cpu(ophead->oh_len); 3440 } else { 3441 idx = BTOBBT((__psint_t)&ophead->oh_len - 3442 (__psint_t)iclog->ic_datap); 3443 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) { 3444 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3445 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3446 op_len = be32_to_cpu(xhdr[j].hic_xheader.xh_cycle_data[k]); 3447 } else { 3448 op_len = be32_to_cpu(iclog->ic_header.h_cycle_data[idx]); 3449 } 3450 } 3451 ptr += sizeof(xlog_op_header_t) + op_len; 3452 } 3453 } /* xlog_verify_iclog */ 3454 #endif 3455 3456 /* 3457 * Mark all iclogs IOERROR. l_icloglock is held by the caller. 3458 */ 3459 STATIC int 3460 xlog_state_ioerror( 3461 xlog_t *log) 3462 { 3463 xlog_in_core_t *iclog, *ic; 3464 3465 iclog = log->l_iclog; 3466 if (! (iclog->ic_state & XLOG_STATE_IOERROR)) { 3467 /* 3468 * Mark all the incore logs IOERROR. 3469 * From now on, no log flushes will result. 3470 */ 3471 ic = iclog; 3472 do { 3473 ic->ic_state = XLOG_STATE_IOERROR; 3474 ic = ic->ic_next; 3475 } while (ic != iclog); 3476 return 0; 3477 } 3478 /* 3479 * Return non-zero, if state transition has already happened. 3480 */ 3481 return 1; 3482 } 3483 3484 /* 3485 * This is called from xfs_force_shutdown, when we're forcibly 3486 * shutting down the filesystem, typically because of an IO error. 3487 * Our main objectives here are to make sure that: 3488 * a. the filesystem gets marked 'SHUTDOWN' for all interested 3489 * parties to find out, 'atomically'. 3490 * b. those who're sleeping on log reservations, pinned objects and 3491 * other resources get woken up, and be told the bad news. 3492 * c. nothing new gets queued up after (a) and (b) are done. 3493 * d. if !logerror, flush the iclogs to disk, then seal them off 3494 * for business. 3495 * 3496 * Note: for delayed logging the !logerror case needs to flush the regions 3497 * held in memory out to the iclogs before flushing them to disk. This needs 3498 * to be done before the log is marked as shutdown, otherwise the flush to the 3499 * iclogs will fail. 3500 */ 3501 int 3502 xfs_log_force_umount( 3503 struct xfs_mount *mp, 3504 int logerror) 3505 { 3506 xlog_t *log; 3507 int retval; 3508 3509 log = mp->m_log; 3510 3511 /* 3512 * If this happens during log recovery, don't worry about 3513 * locking; the log isn't open for business yet. 3514 */ 3515 if (!log || 3516 log->l_flags & XLOG_ACTIVE_RECOVERY) { 3517 mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN; 3518 if (mp->m_sb_bp) 3519 XFS_BUF_DONE(mp->m_sb_bp); 3520 return 0; 3521 } 3522 3523 /* 3524 * Somebody could've already done the hard work for us. 3525 * No need to get locks for this. 3526 */ 3527 if (logerror && log->l_iclog->ic_state & XLOG_STATE_IOERROR) { 3528 ASSERT(XLOG_FORCED_SHUTDOWN(log)); 3529 return 1; 3530 } 3531 retval = 0; 3532 3533 /* 3534 * Flush the in memory commit item list before marking the log as 3535 * being shut down. We need to do it in this order to ensure all the 3536 * completed transactions are flushed to disk with the xfs_log_force() 3537 * call below. 3538 */ 3539 if (!logerror) 3540 xlog_cil_force(log); 3541 3542 /* 3543 * mark the filesystem and the as in a shutdown state and wake 3544 * everybody up to tell them the bad news. 3545 */ 3546 spin_lock(&log->l_icloglock); 3547 mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN; 3548 if (mp->m_sb_bp) 3549 XFS_BUF_DONE(mp->m_sb_bp); 3550 3551 /* 3552 * This flag is sort of redundant because of the mount flag, but 3553 * it's good to maintain the separation between the log and the rest 3554 * of XFS. 3555 */ 3556 log->l_flags |= XLOG_IO_ERROR; 3557 3558 /* 3559 * If we hit a log error, we want to mark all the iclogs IOERROR 3560 * while we're still holding the loglock. 3561 */ 3562 if (logerror) 3563 retval = xlog_state_ioerror(log); 3564 spin_unlock(&log->l_icloglock); 3565 3566 /* 3567 * We don't want anybody waiting for log reservations after this. That 3568 * means we have to wake up everybody queued up on reserveq as well as 3569 * writeq. In addition, we make sure in xlog_{re}grant_log_space that 3570 * we don't enqueue anything once the SHUTDOWN flag is set, and this 3571 * action is protected by the grant locks. 3572 */ 3573 xlog_grant_head_wake_all(&log->l_reserve_head); 3574 xlog_grant_head_wake_all(&log->l_write_head); 3575 3576 if (!(log->l_iclog->ic_state & XLOG_STATE_IOERROR)) { 3577 ASSERT(!logerror); 3578 /* 3579 * Force the incore logs to disk before shutting the 3580 * log down completely. 3581 */ 3582 _xfs_log_force(mp, XFS_LOG_SYNC, NULL); 3583 3584 spin_lock(&log->l_icloglock); 3585 retval = xlog_state_ioerror(log); 3586 spin_unlock(&log->l_icloglock); 3587 } 3588 /* 3589 * Wake up everybody waiting on xfs_log_force. 3590 * Callback all log item committed functions as if the 3591 * log writes were completed. 3592 */ 3593 xlog_state_do_callback(log, XFS_LI_ABORTED, NULL); 3594 3595 #ifdef XFSERRORDEBUG 3596 { 3597 xlog_in_core_t *iclog; 3598 3599 spin_lock(&log->l_icloglock); 3600 iclog = log->l_iclog; 3601 do { 3602 ASSERT(iclog->ic_callback == 0); 3603 iclog = iclog->ic_next; 3604 } while (iclog != log->l_iclog); 3605 spin_unlock(&log->l_icloglock); 3606 } 3607 #endif 3608 /* return non-zero if log IOERROR transition had already happened */ 3609 return retval; 3610 } 3611 3612 STATIC int 3613 xlog_iclogs_empty(xlog_t *log) 3614 { 3615 xlog_in_core_t *iclog; 3616 3617 iclog = log->l_iclog; 3618 do { 3619 /* endianness does not matter here, zero is zero in 3620 * any language. 3621 */ 3622 if (iclog->ic_header.h_num_logops) 3623 return 0; 3624 iclog = iclog->ic_next; 3625 } while (iclog != log->l_iclog); 3626 return 1; 3627 } 3628