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_dir2.h" 28 #include "xfs_dmapi.h" 29 #include "xfs_mount.h" 30 #include "xfs_error.h" 31 #include "xfs_log_priv.h" 32 #include "xfs_buf_item.h" 33 #include "xfs_bmap_btree.h" 34 #include "xfs_alloc_btree.h" 35 #include "xfs_ialloc_btree.h" 36 #include "xfs_log_recover.h" 37 #include "xfs_trans_priv.h" 38 #include "xfs_dir2_sf.h" 39 #include "xfs_attr_sf.h" 40 #include "xfs_dinode.h" 41 #include "xfs_inode.h" 42 #include "xfs_rw.h" 43 #include "xfs_trace.h" 44 45 kmem_zone_t *xfs_log_ticket_zone; 46 47 #define xlog_write_adv_cnt(ptr, len, off, bytes) \ 48 { (ptr) += (bytes); \ 49 (len) -= (bytes); \ 50 (off) += (bytes);} 51 52 /* Local miscellaneous function prototypes */ 53 STATIC int xlog_commit_record(struct log *log, struct xlog_ticket *ticket, 54 xlog_in_core_t **, xfs_lsn_t *); 55 STATIC xlog_t * xlog_alloc_log(xfs_mount_t *mp, 56 xfs_buftarg_t *log_target, 57 xfs_daddr_t blk_offset, 58 int num_bblks); 59 STATIC int xlog_space_left(xlog_t *log, int cycle, int bytes); 60 STATIC int xlog_sync(xlog_t *log, xlog_in_core_t *iclog); 61 STATIC void xlog_dealloc_log(xlog_t *log); 62 STATIC int xlog_write(struct log *log, struct xfs_log_vec *log_vector, 63 struct xlog_ticket *tic, xfs_lsn_t *start_lsn, 64 xlog_in_core_t **commit_iclog, uint flags); 65 66 /* local state machine functions */ 67 STATIC void xlog_state_done_syncing(xlog_in_core_t *iclog, int); 68 STATIC void xlog_state_do_callback(xlog_t *log,int aborted, xlog_in_core_t *iclog); 69 STATIC int xlog_state_get_iclog_space(xlog_t *log, 70 int len, 71 xlog_in_core_t **iclog, 72 xlog_ticket_t *ticket, 73 int *continued_write, 74 int *logoffsetp); 75 STATIC int xlog_state_release_iclog(xlog_t *log, 76 xlog_in_core_t *iclog); 77 STATIC void xlog_state_switch_iclogs(xlog_t *log, 78 xlog_in_core_t *iclog, 79 int eventual_size); 80 STATIC void xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog); 81 82 /* local functions to manipulate grant head */ 83 STATIC int xlog_grant_log_space(xlog_t *log, 84 xlog_ticket_t *xtic); 85 STATIC void xlog_grant_push_ail(xfs_mount_t *mp, 86 int need_bytes); 87 STATIC void xlog_regrant_reserve_log_space(xlog_t *log, 88 xlog_ticket_t *ticket); 89 STATIC int xlog_regrant_write_log_space(xlog_t *log, 90 xlog_ticket_t *ticket); 91 STATIC void xlog_ungrant_log_space(xlog_t *log, 92 xlog_ticket_t *ticket); 93 94 95 /* local ticket functions */ 96 STATIC xlog_ticket_t *xlog_ticket_alloc(xlog_t *log, 97 int unit_bytes, 98 int count, 99 char clientid, 100 uint flags); 101 102 #if defined(DEBUG) 103 STATIC void xlog_verify_dest_ptr(xlog_t *log, __psint_t ptr); 104 STATIC void xlog_verify_grant_head(xlog_t *log, int equals); 105 STATIC void xlog_verify_iclog(xlog_t *log, xlog_in_core_t *iclog, 106 int count, boolean_t syncing); 107 STATIC void xlog_verify_tail_lsn(xlog_t *log, xlog_in_core_t *iclog, 108 xfs_lsn_t tail_lsn); 109 #else 110 #define xlog_verify_dest_ptr(a,b) 111 #define xlog_verify_grant_head(a,b) 112 #define xlog_verify_iclog(a,b,c,d) 113 #define xlog_verify_tail_lsn(a,b,c) 114 #endif 115 116 STATIC int xlog_iclogs_empty(xlog_t *log); 117 118 119 static void 120 xlog_ins_ticketq(struct xlog_ticket **qp, struct xlog_ticket *tic) 121 { 122 if (*qp) { 123 tic->t_next = (*qp); 124 tic->t_prev = (*qp)->t_prev; 125 (*qp)->t_prev->t_next = tic; 126 (*qp)->t_prev = tic; 127 } else { 128 tic->t_prev = tic->t_next = tic; 129 *qp = tic; 130 } 131 132 tic->t_flags |= XLOG_TIC_IN_Q; 133 } 134 135 static void 136 xlog_del_ticketq(struct xlog_ticket **qp, struct xlog_ticket *tic) 137 { 138 if (tic == tic->t_next) { 139 *qp = NULL; 140 } else { 141 *qp = tic->t_next; 142 tic->t_next->t_prev = tic->t_prev; 143 tic->t_prev->t_next = tic->t_next; 144 } 145 146 tic->t_next = tic->t_prev = NULL; 147 tic->t_flags &= ~XLOG_TIC_IN_Q; 148 } 149 150 static void 151 xlog_grant_sub_space(struct log *log, int bytes) 152 { 153 log->l_grant_write_bytes -= bytes; 154 if (log->l_grant_write_bytes < 0) { 155 log->l_grant_write_bytes += log->l_logsize; 156 log->l_grant_write_cycle--; 157 } 158 159 log->l_grant_reserve_bytes -= bytes; 160 if ((log)->l_grant_reserve_bytes < 0) { 161 log->l_grant_reserve_bytes += log->l_logsize; 162 log->l_grant_reserve_cycle--; 163 } 164 165 } 166 167 static void 168 xlog_grant_add_space_write(struct log *log, int bytes) 169 { 170 int tmp = log->l_logsize - log->l_grant_write_bytes; 171 if (tmp > bytes) 172 log->l_grant_write_bytes += bytes; 173 else { 174 log->l_grant_write_cycle++; 175 log->l_grant_write_bytes = bytes - tmp; 176 } 177 } 178 179 static void 180 xlog_grant_add_space_reserve(struct log *log, int bytes) 181 { 182 int tmp = log->l_logsize - log->l_grant_reserve_bytes; 183 if (tmp > bytes) 184 log->l_grant_reserve_bytes += bytes; 185 else { 186 log->l_grant_reserve_cycle++; 187 log->l_grant_reserve_bytes = bytes - tmp; 188 } 189 } 190 191 static inline void 192 xlog_grant_add_space(struct log *log, int bytes) 193 { 194 xlog_grant_add_space_write(log, bytes); 195 xlog_grant_add_space_reserve(log, bytes); 196 } 197 198 static void 199 xlog_tic_reset_res(xlog_ticket_t *tic) 200 { 201 tic->t_res_num = 0; 202 tic->t_res_arr_sum = 0; 203 tic->t_res_num_ophdrs = 0; 204 } 205 206 static void 207 xlog_tic_add_region(xlog_ticket_t *tic, uint len, uint type) 208 { 209 if (tic->t_res_num == XLOG_TIC_LEN_MAX) { 210 /* add to overflow and start again */ 211 tic->t_res_o_flow += tic->t_res_arr_sum; 212 tic->t_res_num = 0; 213 tic->t_res_arr_sum = 0; 214 } 215 216 tic->t_res_arr[tic->t_res_num].r_len = len; 217 tic->t_res_arr[tic->t_res_num].r_type = type; 218 tic->t_res_arr_sum += len; 219 tic->t_res_num++; 220 } 221 222 /* 223 * NOTES: 224 * 225 * 1. currblock field gets updated at startup and after in-core logs 226 * marked as with WANT_SYNC. 227 */ 228 229 /* 230 * This routine is called when a user of a log manager ticket is done with 231 * the reservation. If the ticket was ever used, then a commit record for 232 * the associated transaction is written out as a log operation header with 233 * no data. The flag XLOG_TIC_INITED is set when the first write occurs with 234 * a given ticket. If the ticket was one with a permanent reservation, then 235 * a few operations are done differently. Permanent reservation tickets by 236 * default don't release the reservation. They just commit the current 237 * transaction with the belief that the reservation is still needed. A flag 238 * must be passed in before permanent reservations are actually released. 239 * When these type of tickets are not released, they need to be set into 240 * the inited state again. By doing this, a start record will be written 241 * out when the next write occurs. 242 */ 243 xfs_lsn_t 244 xfs_log_done( 245 struct xfs_mount *mp, 246 struct xlog_ticket *ticket, 247 struct xlog_in_core **iclog, 248 uint flags) 249 { 250 struct log *log = mp->m_log; 251 xfs_lsn_t lsn = 0; 252 253 if (XLOG_FORCED_SHUTDOWN(log) || 254 /* 255 * If nothing was ever written, don't write out commit record. 256 * If we get an error, just continue and give back the log ticket. 257 */ 258 (((ticket->t_flags & XLOG_TIC_INITED) == 0) && 259 (xlog_commit_record(log, ticket, iclog, &lsn)))) { 260 lsn = (xfs_lsn_t) -1; 261 if (ticket->t_flags & XLOG_TIC_PERM_RESERV) { 262 flags |= XFS_LOG_REL_PERM_RESERV; 263 } 264 } 265 266 267 if ((ticket->t_flags & XLOG_TIC_PERM_RESERV) == 0 || 268 (flags & XFS_LOG_REL_PERM_RESERV)) { 269 trace_xfs_log_done_nonperm(log, ticket); 270 271 /* 272 * Release ticket if not permanent reservation or a specific 273 * request has been made to release a permanent reservation. 274 */ 275 xlog_ungrant_log_space(log, ticket); 276 xfs_log_ticket_put(ticket); 277 } else { 278 trace_xfs_log_done_perm(log, ticket); 279 280 xlog_regrant_reserve_log_space(log, ticket); 281 /* If this ticket was a permanent reservation and we aren't 282 * trying to release it, reset the inited flags; so next time 283 * we write, a start record will be written out. 284 */ 285 ticket->t_flags |= XLOG_TIC_INITED; 286 } 287 288 return lsn; 289 } 290 291 /* 292 * Attaches a new iclog I/O completion callback routine during 293 * transaction commit. If the log is in error state, a non-zero 294 * return code is handed back and the caller is responsible for 295 * executing the callback at an appropriate time. 296 */ 297 int 298 xfs_log_notify( 299 struct xfs_mount *mp, 300 struct xlog_in_core *iclog, 301 xfs_log_callback_t *cb) 302 { 303 int abortflg; 304 305 spin_lock(&iclog->ic_callback_lock); 306 abortflg = (iclog->ic_state & XLOG_STATE_IOERROR); 307 if (!abortflg) { 308 ASSERT_ALWAYS((iclog->ic_state == XLOG_STATE_ACTIVE) || 309 (iclog->ic_state == XLOG_STATE_WANT_SYNC)); 310 cb->cb_next = NULL; 311 *(iclog->ic_callback_tail) = cb; 312 iclog->ic_callback_tail = &(cb->cb_next); 313 } 314 spin_unlock(&iclog->ic_callback_lock); 315 return abortflg; 316 } 317 318 int 319 xfs_log_release_iclog( 320 struct xfs_mount *mp, 321 struct xlog_in_core *iclog) 322 { 323 if (xlog_state_release_iclog(mp->m_log, iclog)) { 324 xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR); 325 return EIO; 326 } 327 328 return 0; 329 } 330 331 /* 332 * 1. Reserve an amount of on-disk log space and return a ticket corresponding 333 * to the reservation. 334 * 2. Potentially, push buffers at tail of log to disk. 335 * 336 * Each reservation is going to reserve extra space for a log record header. 337 * When writes happen to the on-disk log, we don't subtract the length of the 338 * log record header from any reservation. By wasting space in each 339 * reservation, we prevent over allocation problems. 340 */ 341 int 342 xfs_log_reserve( 343 struct xfs_mount *mp, 344 int unit_bytes, 345 int cnt, 346 struct xlog_ticket **ticket, 347 __uint8_t client, 348 uint flags, 349 uint t_type) 350 { 351 struct log *log = mp->m_log; 352 struct xlog_ticket *internal_ticket; 353 int retval = 0; 354 355 ASSERT(client == XFS_TRANSACTION || client == XFS_LOG); 356 ASSERT((flags & XFS_LOG_NOSLEEP) == 0); 357 358 if (XLOG_FORCED_SHUTDOWN(log)) 359 return XFS_ERROR(EIO); 360 361 XFS_STATS_INC(xs_try_logspace); 362 363 364 if (*ticket != NULL) { 365 ASSERT(flags & XFS_LOG_PERM_RESERV); 366 internal_ticket = *ticket; 367 368 trace_xfs_log_reserve(log, internal_ticket); 369 370 xlog_grant_push_ail(mp, internal_ticket->t_unit_res); 371 retval = xlog_regrant_write_log_space(log, internal_ticket); 372 } else { 373 /* may sleep if need to allocate more tickets */ 374 internal_ticket = xlog_ticket_alloc(log, unit_bytes, cnt, 375 client, flags); 376 if (!internal_ticket) 377 return XFS_ERROR(ENOMEM); 378 internal_ticket->t_trans_type = t_type; 379 *ticket = internal_ticket; 380 381 trace_xfs_log_reserve(log, internal_ticket); 382 383 xlog_grant_push_ail(mp, 384 (internal_ticket->t_unit_res * 385 internal_ticket->t_cnt)); 386 retval = xlog_grant_log_space(log, internal_ticket); 387 } 388 389 return retval; 390 } /* xfs_log_reserve */ 391 392 393 /* 394 * Mount a log filesystem 395 * 396 * mp - ubiquitous xfs mount point structure 397 * log_target - buftarg of on-disk log device 398 * blk_offset - Start block # where block size is 512 bytes (BBSIZE) 399 * num_bblocks - Number of BBSIZE blocks in on-disk log 400 * 401 * Return error or zero. 402 */ 403 int 404 xfs_log_mount( 405 xfs_mount_t *mp, 406 xfs_buftarg_t *log_target, 407 xfs_daddr_t blk_offset, 408 int num_bblks) 409 { 410 int error; 411 412 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) 413 cmn_err(CE_NOTE, "XFS mounting filesystem %s", mp->m_fsname); 414 else { 415 cmn_err(CE_NOTE, 416 "!Mounting filesystem \"%s\" in no-recovery mode. Filesystem will be inconsistent.", 417 mp->m_fsname); 418 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY); 419 } 420 421 mp->m_log = xlog_alloc_log(mp, log_target, blk_offset, num_bblks); 422 if (IS_ERR(mp->m_log)) { 423 error = -PTR_ERR(mp->m_log); 424 goto out; 425 } 426 427 /* 428 * Initialize the AIL now we have a log. 429 */ 430 error = xfs_trans_ail_init(mp); 431 if (error) { 432 cmn_err(CE_WARN, "XFS: AIL initialisation failed: error %d", error); 433 goto out_free_log; 434 } 435 mp->m_log->l_ailp = mp->m_ail; 436 437 /* 438 * skip log recovery on a norecovery mount. pretend it all 439 * just worked. 440 */ 441 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) { 442 int readonly = (mp->m_flags & XFS_MOUNT_RDONLY); 443 444 if (readonly) 445 mp->m_flags &= ~XFS_MOUNT_RDONLY; 446 447 error = xlog_recover(mp->m_log); 448 449 if (readonly) 450 mp->m_flags |= XFS_MOUNT_RDONLY; 451 if (error) { 452 cmn_err(CE_WARN, "XFS: log mount/recovery failed: error %d", error); 453 goto out_destroy_ail; 454 } 455 } 456 457 /* Normal transactions can now occur */ 458 mp->m_log->l_flags &= ~XLOG_ACTIVE_RECOVERY; 459 460 return 0; 461 462 out_destroy_ail: 463 xfs_trans_ail_destroy(mp); 464 out_free_log: 465 xlog_dealloc_log(mp->m_log); 466 out: 467 return error; 468 } 469 470 /* 471 * Finish the recovery of the file system. This is separate from 472 * the xfs_log_mount() call, because it depends on the code in 473 * xfs_mountfs() to read in the root and real-time bitmap inodes 474 * between calling xfs_log_mount() and here. 475 * 476 * mp - ubiquitous xfs mount point structure 477 */ 478 int 479 xfs_log_mount_finish(xfs_mount_t *mp) 480 { 481 int error; 482 483 if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) 484 error = xlog_recover_finish(mp->m_log); 485 else { 486 error = 0; 487 ASSERT(mp->m_flags & XFS_MOUNT_RDONLY); 488 } 489 490 return error; 491 } 492 493 /* 494 * Final log writes as part of unmount. 495 * 496 * Mark the filesystem clean as unmount happens. Note that during relocation 497 * this routine needs to be executed as part of source-bag while the 498 * deallocation must not be done until source-end. 499 */ 500 501 /* 502 * Unmount record used to have a string "Unmount filesystem--" in the 503 * data section where the "Un" was really a magic number (XLOG_UNMOUNT_TYPE). 504 * We just write the magic number now since that particular field isn't 505 * currently architecture converted and "nUmount" is a bit foo. 506 * As far as I know, there weren't any dependencies on the old behaviour. 507 */ 508 509 int 510 xfs_log_unmount_write(xfs_mount_t *mp) 511 { 512 xlog_t *log = mp->m_log; 513 xlog_in_core_t *iclog; 514 #ifdef DEBUG 515 xlog_in_core_t *first_iclog; 516 #endif 517 xlog_ticket_t *tic = NULL; 518 xfs_lsn_t lsn; 519 int error; 520 521 /* 522 * Don't write out unmount record on read-only mounts. 523 * Or, if we are doing a forced umount (typically because of IO errors). 524 */ 525 if (mp->m_flags & XFS_MOUNT_RDONLY) 526 return 0; 527 528 error = _xfs_log_force(mp, XFS_LOG_SYNC, NULL); 529 ASSERT(error || !(XLOG_FORCED_SHUTDOWN(log))); 530 531 #ifdef DEBUG 532 first_iclog = iclog = log->l_iclog; 533 do { 534 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) { 535 ASSERT(iclog->ic_state & XLOG_STATE_ACTIVE); 536 ASSERT(iclog->ic_offset == 0); 537 } 538 iclog = iclog->ic_next; 539 } while (iclog != first_iclog); 540 #endif 541 if (! (XLOG_FORCED_SHUTDOWN(log))) { 542 error = xfs_log_reserve(mp, 600, 1, &tic, 543 XFS_LOG, 0, XLOG_UNMOUNT_REC_TYPE); 544 if (!error) { 545 /* the data section must be 32 bit size aligned */ 546 struct { 547 __uint16_t magic; 548 __uint16_t pad1; 549 __uint32_t pad2; /* may as well make it 64 bits */ 550 } magic = { 551 .magic = XLOG_UNMOUNT_TYPE, 552 }; 553 struct xfs_log_iovec reg = { 554 .i_addr = (void *)&magic, 555 .i_len = sizeof(magic), 556 .i_type = XLOG_REG_TYPE_UNMOUNT, 557 }; 558 struct xfs_log_vec vec = { 559 .lv_niovecs = 1, 560 .lv_iovecp = ®, 561 }; 562 563 /* remove inited flag */ 564 tic->t_flags = 0; 565 error = xlog_write(log, &vec, tic, &lsn, 566 NULL, XLOG_UNMOUNT_TRANS); 567 /* 568 * At this point, we're umounting anyway, 569 * so there's no point in transitioning log state 570 * to IOERROR. Just continue... 571 */ 572 } 573 574 if (error) { 575 xfs_fs_cmn_err(CE_ALERT, mp, 576 "xfs_log_unmount: unmount record failed"); 577 } 578 579 580 spin_lock(&log->l_icloglock); 581 iclog = log->l_iclog; 582 atomic_inc(&iclog->ic_refcnt); 583 xlog_state_want_sync(log, iclog); 584 spin_unlock(&log->l_icloglock); 585 error = xlog_state_release_iclog(log, iclog); 586 587 spin_lock(&log->l_icloglock); 588 if (!(iclog->ic_state == XLOG_STATE_ACTIVE || 589 iclog->ic_state == XLOG_STATE_DIRTY)) { 590 if (!XLOG_FORCED_SHUTDOWN(log)) { 591 sv_wait(&iclog->ic_force_wait, PMEM, 592 &log->l_icloglock, s); 593 } else { 594 spin_unlock(&log->l_icloglock); 595 } 596 } else { 597 spin_unlock(&log->l_icloglock); 598 } 599 if (tic) { 600 trace_xfs_log_umount_write(log, tic); 601 xlog_ungrant_log_space(log, tic); 602 xfs_log_ticket_put(tic); 603 } 604 } else { 605 /* 606 * We're already in forced_shutdown mode, couldn't 607 * even attempt to write out the unmount transaction. 608 * 609 * Go through the motions of sync'ing and releasing 610 * the iclog, even though no I/O will actually happen, 611 * we need to wait for other log I/Os that may already 612 * be in progress. Do this as a separate section of 613 * code so we'll know if we ever get stuck here that 614 * we're in this odd situation of trying to unmount 615 * a file system that went into forced_shutdown as 616 * the result of an unmount.. 617 */ 618 spin_lock(&log->l_icloglock); 619 iclog = log->l_iclog; 620 atomic_inc(&iclog->ic_refcnt); 621 622 xlog_state_want_sync(log, iclog); 623 spin_unlock(&log->l_icloglock); 624 error = xlog_state_release_iclog(log, iclog); 625 626 spin_lock(&log->l_icloglock); 627 628 if ( ! ( iclog->ic_state == XLOG_STATE_ACTIVE 629 || iclog->ic_state == XLOG_STATE_DIRTY 630 || iclog->ic_state == XLOG_STATE_IOERROR) ) { 631 632 sv_wait(&iclog->ic_force_wait, PMEM, 633 &log->l_icloglock, s); 634 } else { 635 spin_unlock(&log->l_icloglock); 636 } 637 } 638 639 return error; 640 } /* xfs_log_unmount_write */ 641 642 /* 643 * Deallocate log structures for unmount/relocation. 644 * 645 * We need to stop the aild from running before we destroy 646 * and deallocate the log as the aild references the log. 647 */ 648 void 649 xfs_log_unmount(xfs_mount_t *mp) 650 { 651 xfs_trans_ail_destroy(mp); 652 xlog_dealloc_log(mp->m_log); 653 } 654 655 void 656 xfs_log_item_init( 657 struct xfs_mount *mp, 658 struct xfs_log_item *item, 659 int type, 660 struct xfs_item_ops *ops) 661 { 662 item->li_mountp = mp; 663 item->li_ailp = mp->m_ail; 664 item->li_type = type; 665 item->li_ops = ops; 666 } 667 668 /* 669 * Write region vectors to log. The write happens using the space reservation 670 * of the ticket (tic). It is not a requirement that all writes for a given 671 * transaction occur with one call to xfs_log_write(). However, it is important 672 * to note that the transaction reservation code makes an assumption about the 673 * number of log headers a transaction requires that may be violated if you 674 * don't pass all the transaction vectors in one call.... 675 */ 676 int 677 xfs_log_write( 678 struct xfs_mount *mp, 679 struct xfs_log_iovec reg[], 680 int nentries, 681 struct xlog_ticket *tic, 682 xfs_lsn_t *start_lsn) 683 { 684 struct log *log = mp->m_log; 685 int error; 686 struct xfs_log_vec vec = { 687 .lv_niovecs = nentries, 688 .lv_iovecp = reg, 689 }; 690 691 if (XLOG_FORCED_SHUTDOWN(log)) 692 return XFS_ERROR(EIO); 693 694 error = xlog_write(log, &vec, tic, start_lsn, NULL, 0); 695 if (error) 696 xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR); 697 return error; 698 } 699 700 void 701 xfs_log_move_tail(xfs_mount_t *mp, 702 xfs_lsn_t tail_lsn) 703 { 704 xlog_ticket_t *tic; 705 xlog_t *log = mp->m_log; 706 int need_bytes, free_bytes, cycle, bytes; 707 708 if (XLOG_FORCED_SHUTDOWN(log)) 709 return; 710 711 if (tail_lsn == 0) { 712 /* needed since sync_lsn is 64 bits */ 713 spin_lock(&log->l_icloglock); 714 tail_lsn = log->l_last_sync_lsn; 715 spin_unlock(&log->l_icloglock); 716 } 717 718 spin_lock(&log->l_grant_lock); 719 720 /* Also an invalid lsn. 1 implies that we aren't passing in a valid 721 * tail_lsn. 722 */ 723 if (tail_lsn != 1) { 724 log->l_tail_lsn = tail_lsn; 725 } 726 727 if ((tic = log->l_write_headq)) { 728 #ifdef DEBUG 729 if (log->l_flags & XLOG_ACTIVE_RECOVERY) 730 panic("Recovery problem"); 731 #endif 732 cycle = log->l_grant_write_cycle; 733 bytes = log->l_grant_write_bytes; 734 free_bytes = xlog_space_left(log, cycle, bytes); 735 do { 736 ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV); 737 738 if (free_bytes < tic->t_unit_res && tail_lsn != 1) 739 break; 740 tail_lsn = 0; 741 free_bytes -= tic->t_unit_res; 742 sv_signal(&tic->t_wait); 743 tic = tic->t_next; 744 } while (tic != log->l_write_headq); 745 } 746 if ((tic = log->l_reserve_headq)) { 747 #ifdef DEBUG 748 if (log->l_flags & XLOG_ACTIVE_RECOVERY) 749 panic("Recovery problem"); 750 #endif 751 cycle = log->l_grant_reserve_cycle; 752 bytes = log->l_grant_reserve_bytes; 753 free_bytes = xlog_space_left(log, cycle, bytes); 754 do { 755 if (tic->t_flags & XLOG_TIC_PERM_RESERV) 756 need_bytes = tic->t_unit_res*tic->t_cnt; 757 else 758 need_bytes = tic->t_unit_res; 759 if (free_bytes < need_bytes && tail_lsn != 1) 760 break; 761 tail_lsn = 0; 762 free_bytes -= need_bytes; 763 sv_signal(&tic->t_wait); 764 tic = tic->t_next; 765 } while (tic != log->l_reserve_headq); 766 } 767 spin_unlock(&log->l_grant_lock); 768 } /* xfs_log_move_tail */ 769 770 /* 771 * Determine if we have a transaction that has gone to disk 772 * that needs to be covered. To begin the transition to the idle state 773 * firstly the log needs to be idle (no AIL and nothing in the iclogs). 774 * If we are then in a state where covering is needed, the caller is informed 775 * that dummy transactions are required to move the log into the idle state. 776 * 777 * Because this is called as part of the sync process, we should also indicate 778 * that dummy transactions should be issued in anything but the covered or 779 * idle states. This ensures that the log tail is accurately reflected in 780 * the log at the end of the sync, hence if a crash occurrs avoids replay 781 * of transactions where the metadata is already on disk. 782 */ 783 int 784 xfs_log_need_covered(xfs_mount_t *mp) 785 { 786 int needed = 0; 787 xlog_t *log = mp->m_log; 788 789 if (!xfs_fs_writable(mp)) 790 return 0; 791 792 spin_lock(&log->l_icloglock); 793 switch (log->l_covered_state) { 794 case XLOG_STATE_COVER_DONE: 795 case XLOG_STATE_COVER_DONE2: 796 case XLOG_STATE_COVER_IDLE: 797 break; 798 case XLOG_STATE_COVER_NEED: 799 case XLOG_STATE_COVER_NEED2: 800 if (!xfs_trans_ail_tail(log->l_ailp) && 801 xlog_iclogs_empty(log)) { 802 if (log->l_covered_state == XLOG_STATE_COVER_NEED) 803 log->l_covered_state = XLOG_STATE_COVER_DONE; 804 else 805 log->l_covered_state = XLOG_STATE_COVER_DONE2; 806 } 807 /* FALLTHRU */ 808 default: 809 needed = 1; 810 break; 811 } 812 spin_unlock(&log->l_icloglock); 813 return needed; 814 } 815 816 /****************************************************************************** 817 * 818 * local routines 819 * 820 ****************************************************************************** 821 */ 822 823 /* xfs_trans_tail_ail returns 0 when there is nothing in the list. 824 * The log manager must keep track of the last LR which was committed 825 * to disk. The lsn of this LR will become the new tail_lsn whenever 826 * xfs_trans_tail_ail returns 0. If we don't do this, we run into 827 * the situation where stuff could be written into the log but nothing 828 * was ever in the AIL when asked. Eventually, we panic since the 829 * tail hits the head. 830 * 831 * We may be holding the log iclog lock upon entering this routine. 832 */ 833 xfs_lsn_t 834 xlog_assign_tail_lsn(xfs_mount_t *mp) 835 { 836 xfs_lsn_t tail_lsn; 837 xlog_t *log = mp->m_log; 838 839 tail_lsn = xfs_trans_ail_tail(mp->m_ail); 840 spin_lock(&log->l_grant_lock); 841 if (tail_lsn != 0) { 842 log->l_tail_lsn = tail_lsn; 843 } else { 844 tail_lsn = log->l_tail_lsn = log->l_last_sync_lsn; 845 } 846 spin_unlock(&log->l_grant_lock); 847 848 return tail_lsn; 849 } /* xlog_assign_tail_lsn */ 850 851 852 /* 853 * Return the space in the log between the tail and the head. The head 854 * is passed in the cycle/bytes formal parms. In the special case where 855 * the reserve head has wrapped passed the tail, this calculation is no 856 * longer valid. In this case, just return 0 which means there is no space 857 * in the log. This works for all places where this function is called 858 * with the reserve head. Of course, if the write head were to ever 859 * wrap the tail, we should blow up. Rather than catch this case here, 860 * we depend on other ASSERTions in other parts of the code. XXXmiken 861 * 862 * This code also handles the case where the reservation head is behind 863 * the tail. The details of this case are described below, but the end 864 * result is that we return the size of the log as the amount of space left. 865 */ 866 STATIC int 867 xlog_space_left(xlog_t *log, int cycle, int bytes) 868 { 869 int free_bytes; 870 int tail_bytes; 871 int tail_cycle; 872 873 tail_bytes = BBTOB(BLOCK_LSN(log->l_tail_lsn)); 874 tail_cycle = CYCLE_LSN(log->l_tail_lsn); 875 if ((tail_cycle == cycle) && (bytes >= tail_bytes)) { 876 free_bytes = log->l_logsize - (bytes - tail_bytes); 877 } else if ((tail_cycle + 1) < cycle) { 878 return 0; 879 } else if (tail_cycle < cycle) { 880 ASSERT(tail_cycle == (cycle - 1)); 881 free_bytes = tail_bytes - bytes; 882 } else { 883 /* 884 * The reservation head is behind the tail. 885 * In this case we just want to return the size of the 886 * log as the amount of space left. 887 */ 888 xfs_fs_cmn_err(CE_ALERT, log->l_mp, 889 "xlog_space_left: head behind tail\n" 890 " tail_cycle = %d, tail_bytes = %d\n" 891 " GH cycle = %d, GH bytes = %d", 892 tail_cycle, tail_bytes, cycle, bytes); 893 ASSERT(0); 894 free_bytes = log->l_logsize; 895 } 896 return free_bytes; 897 } /* xlog_space_left */ 898 899 900 /* 901 * Log function which is called when an io completes. 902 * 903 * The log manager needs its own routine, in order to control what 904 * happens with the buffer after the write completes. 905 */ 906 void 907 xlog_iodone(xfs_buf_t *bp) 908 { 909 xlog_in_core_t *iclog; 910 xlog_t *l; 911 int aborted; 912 913 iclog = XFS_BUF_FSPRIVATE(bp, xlog_in_core_t *); 914 ASSERT(XFS_BUF_FSPRIVATE2(bp, unsigned long) == (unsigned long) 2); 915 XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)1); 916 aborted = 0; 917 l = iclog->ic_log; 918 919 /* 920 * If the _XFS_BARRIER_FAILED flag was set by a lower 921 * layer, it means the underlying device no longer supports 922 * barrier I/O. Warn loudly and turn off barriers. 923 */ 924 if (bp->b_flags & _XFS_BARRIER_FAILED) { 925 bp->b_flags &= ~_XFS_BARRIER_FAILED; 926 l->l_mp->m_flags &= ~XFS_MOUNT_BARRIER; 927 xfs_fs_cmn_err(CE_WARN, l->l_mp, 928 "xlog_iodone: Barriers are no longer supported" 929 " by device. Disabling barriers\n"); 930 } 931 932 /* 933 * Race to shutdown the filesystem if we see an error. 934 */ 935 if (XFS_TEST_ERROR((XFS_BUF_GETERROR(bp)), l->l_mp, 936 XFS_ERRTAG_IODONE_IOERR, XFS_RANDOM_IODONE_IOERR)) { 937 xfs_ioerror_alert("xlog_iodone", l->l_mp, bp, XFS_BUF_ADDR(bp)); 938 XFS_BUF_STALE(bp); 939 xfs_force_shutdown(l->l_mp, SHUTDOWN_LOG_IO_ERROR); 940 /* 941 * This flag will be propagated to the trans-committed 942 * callback routines to let them know that the log-commit 943 * didn't succeed. 944 */ 945 aborted = XFS_LI_ABORTED; 946 } else if (iclog->ic_state & XLOG_STATE_IOERROR) { 947 aborted = XFS_LI_ABORTED; 948 } 949 950 /* log I/O is always issued ASYNC */ 951 ASSERT(XFS_BUF_ISASYNC(bp)); 952 xlog_state_done_syncing(iclog, aborted); 953 /* 954 * do not reference the buffer (bp) here as we could race 955 * with it being freed after writing the unmount record to the 956 * log. 957 */ 958 959 } /* xlog_iodone */ 960 961 /* 962 * Return size of each in-core log record buffer. 963 * 964 * All machines get 8 x 32kB buffers by default, unless tuned otherwise. 965 * 966 * If the filesystem blocksize is too large, we may need to choose a 967 * larger size since the directory code currently logs entire blocks. 968 */ 969 970 STATIC void 971 xlog_get_iclog_buffer_size(xfs_mount_t *mp, 972 xlog_t *log) 973 { 974 int size; 975 int xhdrs; 976 977 if (mp->m_logbufs <= 0) 978 log->l_iclog_bufs = XLOG_MAX_ICLOGS; 979 else 980 log->l_iclog_bufs = mp->m_logbufs; 981 982 /* 983 * Buffer size passed in from mount system call. 984 */ 985 if (mp->m_logbsize > 0) { 986 size = log->l_iclog_size = mp->m_logbsize; 987 log->l_iclog_size_log = 0; 988 while (size != 1) { 989 log->l_iclog_size_log++; 990 size >>= 1; 991 } 992 993 if (xfs_sb_version_haslogv2(&mp->m_sb)) { 994 /* # headers = size / 32k 995 * one header holds cycles from 32k of data 996 */ 997 998 xhdrs = mp->m_logbsize / XLOG_HEADER_CYCLE_SIZE; 999 if (mp->m_logbsize % XLOG_HEADER_CYCLE_SIZE) 1000 xhdrs++; 1001 log->l_iclog_hsize = xhdrs << BBSHIFT; 1002 log->l_iclog_heads = xhdrs; 1003 } else { 1004 ASSERT(mp->m_logbsize <= XLOG_BIG_RECORD_BSIZE); 1005 log->l_iclog_hsize = BBSIZE; 1006 log->l_iclog_heads = 1; 1007 } 1008 goto done; 1009 } 1010 1011 /* All machines use 32kB buffers by default. */ 1012 log->l_iclog_size = XLOG_BIG_RECORD_BSIZE; 1013 log->l_iclog_size_log = XLOG_BIG_RECORD_BSHIFT; 1014 1015 /* the default log size is 16k or 32k which is one header sector */ 1016 log->l_iclog_hsize = BBSIZE; 1017 log->l_iclog_heads = 1; 1018 1019 done: 1020 /* are we being asked to make the sizes selected above visible? */ 1021 if (mp->m_logbufs == 0) 1022 mp->m_logbufs = log->l_iclog_bufs; 1023 if (mp->m_logbsize == 0) 1024 mp->m_logbsize = log->l_iclog_size; 1025 } /* xlog_get_iclog_buffer_size */ 1026 1027 1028 /* 1029 * This routine initializes some of the log structure for a given mount point. 1030 * Its primary purpose is to fill in enough, so recovery can occur. However, 1031 * some other stuff may be filled in too. 1032 */ 1033 STATIC xlog_t * 1034 xlog_alloc_log(xfs_mount_t *mp, 1035 xfs_buftarg_t *log_target, 1036 xfs_daddr_t blk_offset, 1037 int num_bblks) 1038 { 1039 xlog_t *log; 1040 xlog_rec_header_t *head; 1041 xlog_in_core_t **iclogp; 1042 xlog_in_core_t *iclog, *prev_iclog=NULL; 1043 xfs_buf_t *bp; 1044 int i; 1045 int iclogsize; 1046 int error = ENOMEM; 1047 1048 log = kmem_zalloc(sizeof(xlog_t), KM_MAYFAIL); 1049 if (!log) { 1050 xlog_warn("XFS: Log allocation failed: No memory!"); 1051 goto out; 1052 } 1053 1054 log->l_mp = mp; 1055 log->l_targ = log_target; 1056 log->l_logsize = BBTOB(num_bblks); 1057 log->l_logBBstart = blk_offset; 1058 log->l_logBBsize = num_bblks; 1059 log->l_covered_state = XLOG_STATE_COVER_IDLE; 1060 log->l_flags |= XLOG_ACTIVE_RECOVERY; 1061 1062 log->l_prev_block = -1; 1063 log->l_tail_lsn = xlog_assign_lsn(1, 0); 1064 /* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */ 1065 log->l_last_sync_lsn = log->l_tail_lsn; 1066 log->l_curr_cycle = 1; /* 0 is bad since this is initial value */ 1067 log->l_grant_reserve_cycle = 1; 1068 log->l_grant_write_cycle = 1; 1069 1070 error = EFSCORRUPTED; 1071 if (xfs_sb_version_hassector(&mp->m_sb)) { 1072 log->l_sectbb_log = mp->m_sb.sb_logsectlog - BBSHIFT; 1073 if (log->l_sectbb_log < 0 || 1074 log->l_sectbb_log > mp->m_sectbb_log) { 1075 xlog_warn("XFS: Log sector size (0x%x) out of range.", 1076 log->l_sectbb_log); 1077 goto out_free_log; 1078 } 1079 1080 /* for larger sector sizes, must have v2 or external log */ 1081 if (log->l_sectbb_log != 0 && 1082 (log->l_logBBstart != 0 && 1083 !xfs_sb_version_haslogv2(&mp->m_sb))) { 1084 xlog_warn("XFS: log sector size (0x%x) invalid " 1085 "for configuration.", log->l_sectbb_log); 1086 goto out_free_log; 1087 } 1088 if (mp->m_sb.sb_logsectlog < BBSHIFT) { 1089 xlog_warn("XFS: Log sector log (0x%x) too small.", 1090 mp->m_sb.sb_logsectlog); 1091 goto out_free_log; 1092 } 1093 } 1094 log->l_sectbb_mask = (1 << log->l_sectbb_log) - 1; 1095 1096 xlog_get_iclog_buffer_size(mp, log); 1097 1098 error = ENOMEM; 1099 bp = xfs_buf_get_empty(log->l_iclog_size, mp->m_logdev_targp); 1100 if (!bp) 1101 goto out_free_log; 1102 XFS_BUF_SET_IODONE_FUNC(bp, xlog_iodone); 1103 XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)1); 1104 ASSERT(XFS_BUF_ISBUSY(bp)); 1105 ASSERT(XFS_BUF_VALUSEMA(bp) <= 0); 1106 log->l_xbuf = bp; 1107 1108 spin_lock_init(&log->l_icloglock); 1109 spin_lock_init(&log->l_grant_lock); 1110 sv_init(&log->l_flush_wait, 0, "flush_wait"); 1111 1112 /* log record size must be multiple of BBSIZE; see xlog_rec_header_t */ 1113 ASSERT((XFS_BUF_SIZE(bp) & BBMASK) == 0); 1114 1115 iclogp = &log->l_iclog; 1116 /* 1117 * The amount of memory to allocate for the iclog structure is 1118 * rather funky due to the way the structure is defined. It is 1119 * done this way so that we can use different sizes for machines 1120 * with different amounts of memory. See the definition of 1121 * xlog_in_core_t in xfs_log_priv.h for details. 1122 */ 1123 iclogsize = log->l_iclog_size; 1124 ASSERT(log->l_iclog_size >= 4096); 1125 for (i=0; i < log->l_iclog_bufs; i++) { 1126 *iclogp = kmem_zalloc(sizeof(xlog_in_core_t), KM_MAYFAIL); 1127 if (!*iclogp) 1128 goto out_free_iclog; 1129 1130 iclog = *iclogp; 1131 iclog->ic_prev = prev_iclog; 1132 prev_iclog = iclog; 1133 1134 bp = xfs_buf_get_noaddr(log->l_iclog_size, mp->m_logdev_targp); 1135 if (!bp) 1136 goto out_free_iclog; 1137 if (!XFS_BUF_CPSEMA(bp)) 1138 ASSERT(0); 1139 XFS_BUF_SET_IODONE_FUNC(bp, xlog_iodone); 1140 XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)1); 1141 iclog->ic_bp = bp; 1142 iclog->ic_data = bp->b_addr; 1143 #ifdef DEBUG 1144 log->l_iclog_bak[i] = (xfs_caddr_t)&(iclog->ic_header); 1145 #endif 1146 head = &iclog->ic_header; 1147 memset(head, 0, sizeof(xlog_rec_header_t)); 1148 head->h_magicno = cpu_to_be32(XLOG_HEADER_MAGIC_NUM); 1149 head->h_version = cpu_to_be32( 1150 xfs_sb_version_haslogv2(&log->l_mp->m_sb) ? 2 : 1); 1151 head->h_size = cpu_to_be32(log->l_iclog_size); 1152 /* new fields */ 1153 head->h_fmt = cpu_to_be32(XLOG_FMT); 1154 memcpy(&head->h_fs_uuid, &mp->m_sb.sb_uuid, sizeof(uuid_t)); 1155 1156 iclog->ic_size = XFS_BUF_SIZE(bp) - log->l_iclog_hsize; 1157 iclog->ic_state = XLOG_STATE_ACTIVE; 1158 iclog->ic_log = log; 1159 atomic_set(&iclog->ic_refcnt, 0); 1160 spin_lock_init(&iclog->ic_callback_lock); 1161 iclog->ic_callback_tail = &(iclog->ic_callback); 1162 iclog->ic_datap = (char *)iclog->ic_data + log->l_iclog_hsize; 1163 1164 ASSERT(XFS_BUF_ISBUSY(iclog->ic_bp)); 1165 ASSERT(XFS_BUF_VALUSEMA(iclog->ic_bp) <= 0); 1166 sv_init(&iclog->ic_force_wait, SV_DEFAULT, "iclog-force"); 1167 sv_init(&iclog->ic_write_wait, SV_DEFAULT, "iclog-write"); 1168 1169 iclogp = &iclog->ic_next; 1170 } 1171 *iclogp = log->l_iclog; /* complete ring */ 1172 log->l_iclog->ic_prev = prev_iclog; /* re-write 1st prev ptr */ 1173 1174 return log; 1175 1176 out_free_iclog: 1177 for (iclog = log->l_iclog; iclog; iclog = prev_iclog) { 1178 prev_iclog = iclog->ic_next; 1179 if (iclog->ic_bp) { 1180 sv_destroy(&iclog->ic_force_wait); 1181 sv_destroy(&iclog->ic_write_wait); 1182 xfs_buf_free(iclog->ic_bp); 1183 } 1184 kmem_free(iclog); 1185 } 1186 spinlock_destroy(&log->l_icloglock); 1187 spinlock_destroy(&log->l_grant_lock); 1188 xfs_buf_free(log->l_xbuf); 1189 out_free_log: 1190 kmem_free(log); 1191 out: 1192 return ERR_PTR(-error); 1193 } /* xlog_alloc_log */ 1194 1195 1196 /* 1197 * Write out the commit record of a transaction associated with the given 1198 * ticket. Return the lsn of the commit record. 1199 */ 1200 STATIC int 1201 xlog_commit_record( 1202 struct log *log, 1203 struct xlog_ticket *ticket, 1204 struct xlog_in_core **iclog, 1205 xfs_lsn_t *commitlsnp) 1206 { 1207 struct xfs_mount *mp = log->l_mp; 1208 int error; 1209 struct xfs_log_iovec reg = { 1210 .i_addr = NULL, 1211 .i_len = 0, 1212 .i_type = XLOG_REG_TYPE_COMMIT, 1213 }; 1214 struct xfs_log_vec vec = { 1215 .lv_niovecs = 1, 1216 .lv_iovecp = ®, 1217 }; 1218 1219 ASSERT_ALWAYS(iclog); 1220 error = xlog_write(log, &vec, ticket, commitlsnp, iclog, 1221 XLOG_COMMIT_TRANS); 1222 if (error) 1223 xfs_force_shutdown(mp, SHUTDOWN_LOG_IO_ERROR); 1224 return error; 1225 } 1226 1227 /* 1228 * Push on the buffer cache code if we ever use more than 75% of the on-disk 1229 * log space. This code pushes on the lsn which would supposedly free up 1230 * the 25% which we want to leave free. We may need to adopt a policy which 1231 * pushes on an lsn which is further along in the log once we reach the high 1232 * water mark. In this manner, we would be creating a low water mark. 1233 */ 1234 STATIC void 1235 xlog_grant_push_ail(xfs_mount_t *mp, 1236 int need_bytes) 1237 { 1238 xlog_t *log = mp->m_log; /* pointer to the log */ 1239 xfs_lsn_t tail_lsn; /* lsn of the log tail */ 1240 xfs_lsn_t threshold_lsn = 0; /* lsn we'd like to be at */ 1241 int free_blocks; /* free blocks left to write to */ 1242 int free_bytes; /* free bytes left to write to */ 1243 int threshold_block; /* block in lsn we'd like to be at */ 1244 int threshold_cycle; /* lsn cycle we'd like to be at */ 1245 int free_threshold; 1246 1247 ASSERT(BTOBB(need_bytes) < log->l_logBBsize); 1248 1249 spin_lock(&log->l_grant_lock); 1250 free_bytes = xlog_space_left(log, 1251 log->l_grant_reserve_cycle, 1252 log->l_grant_reserve_bytes); 1253 tail_lsn = log->l_tail_lsn; 1254 free_blocks = BTOBBT(free_bytes); 1255 1256 /* 1257 * Set the threshold for the minimum number of free blocks in the 1258 * log to the maximum of what the caller needs, one quarter of the 1259 * log, and 256 blocks. 1260 */ 1261 free_threshold = BTOBB(need_bytes); 1262 free_threshold = MAX(free_threshold, (log->l_logBBsize >> 2)); 1263 free_threshold = MAX(free_threshold, 256); 1264 if (free_blocks < free_threshold) { 1265 threshold_block = BLOCK_LSN(tail_lsn) + free_threshold; 1266 threshold_cycle = CYCLE_LSN(tail_lsn); 1267 if (threshold_block >= log->l_logBBsize) { 1268 threshold_block -= log->l_logBBsize; 1269 threshold_cycle += 1; 1270 } 1271 threshold_lsn = xlog_assign_lsn(threshold_cycle, threshold_block); 1272 1273 /* Don't pass in an lsn greater than the lsn of the last 1274 * log record known to be on disk. 1275 */ 1276 if (XFS_LSN_CMP(threshold_lsn, log->l_last_sync_lsn) > 0) 1277 threshold_lsn = log->l_last_sync_lsn; 1278 } 1279 spin_unlock(&log->l_grant_lock); 1280 1281 /* 1282 * Get the transaction layer to kick the dirty buffers out to 1283 * disk asynchronously. No point in trying to do this if 1284 * the filesystem is shutting down. 1285 */ 1286 if (threshold_lsn && 1287 !XLOG_FORCED_SHUTDOWN(log)) 1288 xfs_trans_ail_push(log->l_ailp, threshold_lsn); 1289 } /* xlog_grant_push_ail */ 1290 1291 /* 1292 * The bdstrat callback function for log bufs. This gives us a central 1293 * place to trap bufs in case we get hit by a log I/O error and need to 1294 * shutdown. Actually, in practice, even when we didn't get a log error, 1295 * we transition the iclogs to IOERROR state *after* flushing all existing 1296 * iclogs to disk. This is because we don't want anymore new transactions to be 1297 * started or completed afterwards. 1298 */ 1299 STATIC int 1300 xlog_bdstrat( 1301 struct xfs_buf *bp) 1302 { 1303 struct xlog_in_core *iclog; 1304 1305 iclog = XFS_BUF_FSPRIVATE(bp, xlog_in_core_t *); 1306 if (iclog->ic_state & XLOG_STATE_IOERROR) { 1307 XFS_BUF_ERROR(bp, EIO); 1308 XFS_BUF_STALE(bp); 1309 xfs_biodone(bp); 1310 /* 1311 * It would seem logical to return EIO here, but we rely on 1312 * the log state machine to propagate I/O errors instead of 1313 * doing it here. 1314 */ 1315 return 0; 1316 } 1317 1318 bp->b_flags |= _XBF_RUN_QUEUES; 1319 xfs_buf_iorequest(bp); 1320 return 0; 1321 } 1322 1323 /* 1324 * Flush out the in-core log (iclog) to the on-disk log in an asynchronous 1325 * fashion. Previously, we should have moved the current iclog 1326 * ptr in the log to point to the next available iclog. This allows further 1327 * write to continue while this code syncs out an iclog ready to go. 1328 * Before an in-core log can be written out, the data section must be scanned 1329 * to save away the 1st word of each BBSIZE block into the header. We replace 1330 * it with the current cycle count. Each BBSIZE block is tagged with the 1331 * cycle count because there in an implicit assumption that drives will 1332 * guarantee that entire 512 byte blocks get written at once. In other words, 1333 * we can't have part of a 512 byte block written and part not written. By 1334 * tagging each block, we will know which blocks are valid when recovering 1335 * after an unclean shutdown. 1336 * 1337 * This routine is single threaded on the iclog. No other thread can be in 1338 * this routine with the same iclog. Changing contents of iclog can there- 1339 * fore be done without grabbing the state machine lock. Updating the global 1340 * log will require grabbing the lock though. 1341 * 1342 * The entire log manager uses a logical block numbering scheme. Only 1343 * log_sync (and then only bwrite()) know about the fact that the log may 1344 * not start with block zero on a given device. The log block start offset 1345 * is added immediately before calling bwrite(). 1346 */ 1347 1348 STATIC int 1349 xlog_sync(xlog_t *log, 1350 xlog_in_core_t *iclog) 1351 { 1352 xfs_caddr_t dptr; /* pointer to byte sized element */ 1353 xfs_buf_t *bp; 1354 int i; 1355 uint count; /* byte count of bwrite */ 1356 uint count_init; /* initial count before roundup */ 1357 int roundoff; /* roundoff to BB or stripe */ 1358 int split = 0; /* split write into two regions */ 1359 int error; 1360 int v2 = xfs_sb_version_haslogv2(&log->l_mp->m_sb); 1361 1362 XFS_STATS_INC(xs_log_writes); 1363 ASSERT(atomic_read(&iclog->ic_refcnt) == 0); 1364 1365 /* Add for LR header */ 1366 count_init = log->l_iclog_hsize + iclog->ic_offset; 1367 1368 /* Round out the log write size */ 1369 if (v2 && log->l_mp->m_sb.sb_logsunit > 1) { 1370 /* we have a v2 stripe unit to use */ 1371 count = XLOG_LSUNITTOB(log, XLOG_BTOLSUNIT(log, count_init)); 1372 } else { 1373 count = BBTOB(BTOBB(count_init)); 1374 } 1375 roundoff = count - count_init; 1376 ASSERT(roundoff >= 0); 1377 ASSERT((v2 && log->l_mp->m_sb.sb_logsunit > 1 && 1378 roundoff < log->l_mp->m_sb.sb_logsunit) 1379 || 1380 (log->l_mp->m_sb.sb_logsunit <= 1 && 1381 roundoff < BBTOB(1))); 1382 1383 /* move grant heads by roundoff in sync */ 1384 spin_lock(&log->l_grant_lock); 1385 xlog_grant_add_space(log, roundoff); 1386 spin_unlock(&log->l_grant_lock); 1387 1388 /* put cycle number in every block */ 1389 xlog_pack_data(log, iclog, roundoff); 1390 1391 /* real byte length */ 1392 if (v2) { 1393 iclog->ic_header.h_len = 1394 cpu_to_be32(iclog->ic_offset + roundoff); 1395 } else { 1396 iclog->ic_header.h_len = 1397 cpu_to_be32(iclog->ic_offset); 1398 } 1399 1400 bp = iclog->ic_bp; 1401 ASSERT(XFS_BUF_FSPRIVATE2(bp, unsigned long) == (unsigned long)1); 1402 XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)2); 1403 XFS_BUF_SET_ADDR(bp, BLOCK_LSN(be64_to_cpu(iclog->ic_header.h_lsn))); 1404 1405 XFS_STATS_ADD(xs_log_blocks, BTOBB(count)); 1406 1407 /* Do we need to split this write into 2 parts? */ 1408 if (XFS_BUF_ADDR(bp) + BTOBB(count) > log->l_logBBsize) { 1409 split = count - (BBTOB(log->l_logBBsize - XFS_BUF_ADDR(bp))); 1410 count = BBTOB(log->l_logBBsize - XFS_BUF_ADDR(bp)); 1411 iclog->ic_bwritecnt = 2; /* split into 2 writes */ 1412 } else { 1413 iclog->ic_bwritecnt = 1; 1414 } 1415 XFS_BUF_SET_COUNT(bp, count); 1416 XFS_BUF_SET_FSPRIVATE(bp, iclog); /* save for later */ 1417 XFS_BUF_ZEROFLAGS(bp); 1418 XFS_BUF_BUSY(bp); 1419 XFS_BUF_ASYNC(bp); 1420 bp->b_flags |= XBF_LOG_BUFFER; 1421 /* 1422 * Do an ordered write for the log block. 1423 * Its unnecessary to flush the first split block in the log wrap case. 1424 */ 1425 if (!split && (log->l_mp->m_flags & XFS_MOUNT_BARRIER)) 1426 XFS_BUF_ORDERED(bp); 1427 1428 ASSERT(XFS_BUF_ADDR(bp) <= log->l_logBBsize-1); 1429 ASSERT(XFS_BUF_ADDR(bp) + BTOBB(count) <= log->l_logBBsize); 1430 1431 xlog_verify_iclog(log, iclog, count, B_TRUE); 1432 1433 /* account for log which doesn't start at block #0 */ 1434 XFS_BUF_SET_ADDR(bp, XFS_BUF_ADDR(bp) + log->l_logBBstart); 1435 /* 1436 * Don't call xfs_bwrite here. We do log-syncs even when the filesystem 1437 * is shutting down. 1438 */ 1439 XFS_BUF_WRITE(bp); 1440 1441 if ((error = xlog_bdstrat(bp))) { 1442 xfs_ioerror_alert("xlog_sync", log->l_mp, bp, 1443 XFS_BUF_ADDR(bp)); 1444 return error; 1445 } 1446 if (split) { 1447 bp = iclog->ic_log->l_xbuf; 1448 ASSERT(XFS_BUF_FSPRIVATE2(bp, unsigned long) == 1449 (unsigned long)1); 1450 XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)2); 1451 XFS_BUF_SET_ADDR(bp, 0); /* logical 0 */ 1452 XFS_BUF_SET_PTR(bp, (xfs_caddr_t)((__psint_t)&(iclog->ic_header)+ 1453 (__psint_t)count), split); 1454 XFS_BUF_SET_FSPRIVATE(bp, iclog); 1455 XFS_BUF_ZEROFLAGS(bp); 1456 XFS_BUF_BUSY(bp); 1457 XFS_BUF_ASYNC(bp); 1458 bp->b_flags |= XBF_LOG_BUFFER; 1459 if (log->l_mp->m_flags & XFS_MOUNT_BARRIER) 1460 XFS_BUF_ORDERED(bp); 1461 dptr = XFS_BUF_PTR(bp); 1462 /* 1463 * Bump the cycle numbers at the start of each block 1464 * since this part of the buffer is at the start of 1465 * a new cycle. Watch out for the header magic number 1466 * case, though. 1467 */ 1468 for (i = 0; i < split; i += BBSIZE) { 1469 be32_add_cpu((__be32 *)dptr, 1); 1470 if (be32_to_cpu(*(__be32 *)dptr) == XLOG_HEADER_MAGIC_NUM) 1471 be32_add_cpu((__be32 *)dptr, 1); 1472 dptr += BBSIZE; 1473 } 1474 1475 ASSERT(XFS_BUF_ADDR(bp) <= log->l_logBBsize-1); 1476 ASSERT(XFS_BUF_ADDR(bp) + BTOBB(count) <= log->l_logBBsize); 1477 1478 /* account for internal log which doesn't start at block #0 */ 1479 XFS_BUF_SET_ADDR(bp, XFS_BUF_ADDR(bp) + log->l_logBBstart); 1480 XFS_BUF_WRITE(bp); 1481 if ((error = xlog_bdstrat(bp))) { 1482 xfs_ioerror_alert("xlog_sync (split)", log->l_mp, 1483 bp, XFS_BUF_ADDR(bp)); 1484 return error; 1485 } 1486 } 1487 return 0; 1488 } /* xlog_sync */ 1489 1490 1491 /* 1492 * Deallocate a log structure 1493 */ 1494 STATIC void 1495 xlog_dealloc_log(xlog_t *log) 1496 { 1497 xlog_in_core_t *iclog, *next_iclog; 1498 int i; 1499 1500 iclog = log->l_iclog; 1501 for (i=0; i<log->l_iclog_bufs; i++) { 1502 sv_destroy(&iclog->ic_force_wait); 1503 sv_destroy(&iclog->ic_write_wait); 1504 xfs_buf_free(iclog->ic_bp); 1505 next_iclog = iclog->ic_next; 1506 kmem_free(iclog); 1507 iclog = next_iclog; 1508 } 1509 spinlock_destroy(&log->l_icloglock); 1510 spinlock_destroy(&log->l_grant_lock); 1511 1512 xfs_buf_free(log->l_xbuf); 1513 log->l_mp->m_log = NULL; 1514 kmem_free(log); 1515 } /* xlog_dealloc_log */ 1516 1517 /* 1518 * Update counters atomically now that memcpy is done. 1519 */ 1520 /* ARGSUSED */ 1521 static inline void 1522 xlog_state_finish_copy(xlog_t *log, 1523 xlog_in_core_t *iclog, 1524 int record_cnt, 1525 int copy_bytes) 1526 { 1527 spin_lock(&log->l_icloglock); 1528 1529 be32_add_cpu(&iclog->ic_header.h_num_logops, record_cnt); 1530 iclog->ic_offset += copy_bytes; 1531 1532 spin_unlock(&log->l_icloglock); 1533 } /* xlog_state_finish_copy */ 1534 1535 1536 1537 1538 /* 1539 * print out info relating to regions written which consume 1540 * the reservation 1541 */ 1542 STATIC void 1543 xlog_print_tic_res(xfs_mount_t *mp, xlog_ticket_t *ticket) 1544 { 1545 uint i; 1546 uint ophdr_spc = ticket->t_res_num_ophdrs * (uint)sizeof(xlog_op_header_t); 1547 1548 /* match with XLOG_REG_TYPE_* in xfs_log.h */ 1549 static char *res_type_str[XLOG_REG_TYPE_MAX] = { 1550 "bformat", 1551 "bchunk", 1552 "efi_format", 1553 "efd_format", 1554 "iformat", 1555 "icore", 1556 "iext", 1557 "ibroot", 1558 "ilocal", 1559 "iattr_ext", 1560 "iattr_broot", 1561 "iattr_local", 1562 "qformat", 1563 "dquot", 1564 "quotaoff", 1565 "LR header", 1566 "unmount", 1567 "commit", 1568 "trans header" 1569 }; 1570 static char *trans_type_str[XFS_TRANS_TYPE_MAX] = { 1571 "SETATTR_NOT_SIZE", 1572 "SETATTR_SIZE", 1573 "INACTIVE", 1574 "CREATE", 1575 "CREATE_TRUNC", 1576 "TRUNCATE_FILE", 1577 "REMOVE", 1578 "LINK", 1579 "RENAME", 1580 "MKDIR", 1581 "RMDIR", 1582 "SYMLINK", 1583 "SET_DMATTRS", 1584 "GROWFS", 1585 "STRAT_WRITE", 1586 "DIOSTRAT", 1587 "WRITE_SYNC", 1588 "WRITEID", 1589 "ADDAFORK", 1590 "ATTRINVAL", 1591 "ATRUNCATE", 1592 "ATTR_SET", 1593 "ATTR_RM", 1594 "ATTR_FLAG", 1595 "CLEAR_AGI_BUCKET", 1596 "QM_SBCHANGE", 1597 "DUMMY1", 1598 "DUMMY2", 1599 "QM_QUOTAOFF", 1600 "QM_DQALLOC", 1601 "QM_SETQLIM", 1602 "QM_DQCLUSTER", 1603 "QM_QINOCREATE", 1604 "QM_QUOTAOFF_END", 1605 "SB_UNIT", 1606 "FSYNC_TS", 1607 "GROWFSRT_ALLOC", 1608 "GROWFSRT_ZERO", 1609 "GROWFSRT_FREE", 1610 "SWAPEXT" 1611 }; 1612 1613 xfs_fs_cmn_err(CE_WARN, mp, 1614 "xfs_log_write: reservation summary:\n" 1615 " trans type = %s (%u)\n" 1616 " unit res = %d bytes\n" 1617 " current res = %d bytes\n" 1618 " total reg = %u bytes (o/flow = %u bytes)\n" 1619 " ophdrs = %u (ophdr space = %u bytes)\n" 1620 " ophdr + reg = %u bytes\n" 1621 " num regions = %u\n", 1622 ((ticket->t_trans_type <= 0 || 1623 ticket->t_trans_type > XFS_TRANS_TYPE_MAX) ? 1624 "bad-trans-type" : trans_type_str[ticket->t_trans_type-1]), 1625 ticket->t_trans_type, 1626 ticket->t_unit_res, 1627 ticket->t_curr_res, 1628 ticket->t_res_arr_sum, ticket->t_res_o_flow, 1629 ticket->t_res_num_ophdrs, ophdr_spc, 1630 ticket->t_res_arr_sum + 1631 ticket->t_res_o_flow + ophdr_spc, 1632 ticket->t_res_num); 1633 1634 for (i = 0; i < ticket->t_res_num; i++) { 1635 uint r_type = ticket->t_res_arr[i].r_type; 1636 cmn_err(CE_WARN, 1637 "region[%u]: %s - %u bytes\n", 1638 i, 1639 ((r_type <= 0 || r_type > XLOG_REG_TYPE_MAX) ? 1640 "bad-rtype" : res_type_str[r_type-1]), 1641 ticket->t_res_arr[i].r_len); 1642 } 1643 } 1644 1645 /* 1646 * Calculate the potential space needed by the log vector. Each region gets 1647 * its own xlog_op_header_t and may need to be double word aligned. 1648 */ 1649 static int 1650 xlog_write_calc_vec_length( 1651 struct xlog_ticket *ticket, 1652 struct xfs_log_vec *log_vector) 1653 { 1654 struct xfs_log_vec *lv; 1655 int headers = 0; 1656 int len = 0; 1657 int i; 1658 1659 /* acct for start rec of xact */ 1660 if (ticket->t_flags & XLOG_TIC_INITED) 1661 headers++; 1662 1663 for (lv = log_vector; lv; lv = lv->lv_next) { 1664 headers += lv->lv_niovecs; 1665 1666 for (i = 0; i < lv->lv_niovecs; i++) { 1667 struct xfs_log_iovec *vecp = &lv->lv_iovecp[i]; 1668 1669 len += vecp->i_len; 1670 xlog_tic_add_region(ticket, vecp->i_len, vecp->i_type); 1671 } 1672 } 1673 1674 ticket->t_res_num_ophdrs += headers; 1675 len += headers * sizeof(struct xlog_op_header); 1676 1677 return len; 1678 } 1679 1680 /* 1681 * If first write for transaction, insert start record We can't be trying to 1682 * commit if we are inited. We can't have any "partial_copy" if we are inited. 1683 */ 1684 static int 1685 xlog_write_start_rec( 1686 __psint_t ptr, 1687 struct xlog_ticket *ticket) 1688 { 1689 struct xlog_op_header *ophdr = (struct xlog_op_header *)ptr; 1690 1691 if (!(ticket->t_flags & XLOG_TIC_INITED)) 1692 return 0; 1693 1694 ophdr->oh_tid = cpu_to_be32(ticket->t_tid); 1695 ophdr->oh_clientid = ticket->t_clientid; 1696 ophdr->oh_len = 0; 1697 ophdr->oh_flags = XLOG_START_TRANS; 1698 ophdr->oh_res2 = 0; 1699 1700 ticket->t_flags &= ~XLOG_TIC_INITED; 1701 1702 return sizeof(struct xlog_op_header); 1703 } 1704 1705 static xlog_op_header_t * 1706 xlog_write_setup_ophdr( 1707 struct log *log, 1708 __psint_t ptr, 1709 struct xlog_ticket *ticket, 1710 uint flags) 1711 { 1712 struct xlog_op_header *ophdr = (struct xlog_op_header *)ptr; 1713 1714 ophdr->oh_tid = cpu_to_be32(ticket->t_tid); 1715 ophdr->oh_clientid = ticket->t_clientid; 1716 ophdr->oh_res2 = 0; 1717 1718 /* are we copying a commit or unmount record? */ 1719 ophdr->oh_flags = flags; 1720 1721 /* 1722 * We've seen logs corrupted with bad transaction client ids. This 1723 * makes sure that XFS doesn't generate them on. Turn this into an EIO 1724 * and shut down the filesystem. 1725 */ 1726 switch (ophdr->oh_clientid) { 1727 case XFS_TRANSACTION: 1728 case XFS_VOLUME: 1729 case XFS_LOG: 1730 break; 1731 default: 1732 xfs_fs_cmn_err(CE_WARN, log->l_mp, 1733 "Bad XFS transaction clientid 0x%x in ticket 0x%p", 1734 ophdr->oh_clientid, ticket); 1735 return NULL; 1736 } 1737 1738 return ophdr; 1739 } 1740 1741 /* 1742 * Set up the parameters of the region copy into the log. This has 1743 * to handle region write split across multiple log buffers - this 1744 * state is kept external to this function so that this code can 1745 * can be written in an obvious, self documenting manner. 1746 */ 1747 static int 1748 xlog_write_setup_copy( 1749 struct xlog_ticket *ticket, 1750 struct xlog_op_header *ophdr, 1751 int space_available, 1752 int space_required, 1753 int *copy_off, 1754 int *copy_len, 1755 int *last_was_partial_copy, 1756 int *bytes_consumed) 1757 { 1758 int still_to_copy; 1759 1760 still_to_copy = space_required - *bytes_consumed; 1761 *copy_off = *bytes_consumed; 1762 1763 if (still_to_copy <= space_available) { 1764 /* write of region completes here */ 1765 *copy_len = still_to_copy; 1766 ophdr->oh_len = cpu_to_be32(*copy_len); 1767 if (*last_was_partial_copy) 1768 ophdr->oh_flags |= (XLOG_END_TRANS|XLOG_WAS_CONT_TRANS); 1769 *last_was_partial_copy = 0; 1770 *bytes_consumed = 0; 1771 return 0; 1772 } 1773 1774 /* partial write of region, needs extra log op header reservation */ 1775 *copy_len = space_available; 1776 ophdr->oh_len = cpu_to_be32(*copy_len); 1777 ophdr->oh_flags |= XLOG_CONTINUE_TRANS; 1778 if (*last_was_partial_copy) 1779 ophdr->oh_flags |= XLOG_WAS_CONT_TRANS; 1780 *bytes_consumed += *copy_len; 1781 (*last_was_partial_copy)++; 1782 1783 /* account for new log op header */ 1784 ticket->t_curr_res -= sizeof(struct xlog_op_header); 1785 ticket->t_res_num_ophdrs++; 1786 1787 return sizeof(struct xlog_op_header); 1788 } 1789 1790 static int 1791 xlog_write_copy_finish( 1792 struct log *log, 1793 struct xlog_in_core *iclog, 1794 uint flags, 1795 int *record_cnt, 1796 int *data_cnt, 1797 int *partial_copy, 1798 int *partial_copy_len, 1799 int log_offset, 1800 struct xlog_in_core **commit_iclog) 1801 { 1802 if (*partial_copy) { 1803 /* 1804 * This iclog has already been marked WANT_SYNC by 1805 * xlog_state_get_iclog_space. 1806 */ 1807 xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt); 1808 *record_cnt = 0; 1809 *data_cnt = 0; 1810 return xlog_state_release_iclog(log, iclog); 1811 } 1812 1813 *partial_copy = 0; 1814 *partial_copy_len = 0; 1815 1816 if (iclog->ic_size - log_offset <= sizeof(xlog_op_header_t)) { 1817 /* no more space in this iclog - push it. */ 1818 xlog_state_finish_copy(log, iclog, *record_cnt, *data_cnt); 1819 *record_cnt = 0; 1820 *data_cnt = 0; 1821 1822 spin_lock(&log->l_icloglock); 1823 xlog_state_want_sync(log, iclog); 1824 spin_unlock(&log->l_icloglock); 1825 1826 if (!commit_iclog) 1827 return xlog_state_release_iclog(log, iclog); 1828 ASSERT(flags & XLOG_COMMIT_TRANS); 1829 *commit_iclog = iclog; 1830 } 1831 1832 return 0; 1833 } 1834 1835 /* 1836 * Write some region out to in-core log 1837 * 1838 * This will be called when writing externally provided regions or when 1839 * writing out a commit record for a given transaction. 1840 * 1841 * General algorithm: 1842 * 1. Find total length of this write. This may include adding to the 1843 * lengths passed in. 1844 * 2. Check whether we violate the tickets reservation. 1845 * 3. While writing to this iclog 1846 * A. Reserve as much space in this iclog as can get 1847 * B. If this is first write, save away start lsn 1848 * C. While writing this region: 1849 * 1. If first write of transaction, write start record 1850 * 2. Write log operation header (header per region) 1851 * 3. Find out if we can fit entire region into this iclog 1852 * 4. Potentially, verify destination memcpy ptr 1853 * 5. Memcpy (partial) region 1854 * 6. If partial copy, release iclog; otherwise, continue 1855 * copying more regions into current iclog 1856 * 4. Mark want sync bit (in simulation mode) 1857 * 5. Release iclog for potential flush to on-disk log. 1858 * 1859 * ERRORS: 1860 * 1. Panic if reservation is overrun. This should never happen since 1861 * reservation amounts are generated internal to the filesystem. 1862 * NOTES: 1863 * 1. Tickets are single threaded data structures. 1864 * 2. The XLOG_END_TRANS & XLOG_CONTINUE_TRANS flags are passed down to the 1865 * syncing routine. When a single log_write region needs to span 1866 * multiple in-core logs, the XLOG_CONTINUE_TRANS bit should be set 1867 * on all log operation writes which don't contain the end of the 1868 * region. The XLOG_END_TRANS bit is used for the in-core log 1869 * operation which contains the end of the continued log_write region. 1870 * 3. When xlog_state_get_iclog_space() grabs the rest of the current iclog, 1871 * we don't really know exactly how much space will be used. As a result, 1872 * we don't update ic_offset until the end when we know exactly how many 1873 * bytes have been written out. 1874 */ 1875 STATIC int 1876 xlog_write( 1877 struct log *log, 1878 struct xfs_log_vec *log_vector, 1879 struct xlog_ticket *ticket, 1880 xfs_lsn_t *start_lsn, 1881 struct xlog_in_core **commit_iclog, 1882 uint flags) 1883 { 1884 struct xlog_in_core *iclog = NULL; 1885 struct xfs_log_iovec *vecp; 1886 struct xfs_log_vec *lv; 1887 int len; 1888 int index; 1889 int partial_copy = 0; 1890 int partial_copy_len = 0; 1891 int contwr = 0; 1892 int record_cnt = 0; 1893 int data_cnt = 0; 1894 int error; 1895 1896 *start_lsn = 0; 1897 1898 len = xlog_write_calc_vec_length(ticket, log_vector); 1899 if (ticket->t_curr_res < len) { 1900 xlog_print_tic_res(log->l_mp, ticket); 1901 #ifdef DEBUG 1902 xlog_panic( 1903 "xfs_log_write: reservation ran out. Need to up reservation"); 1904 #else 1905 /* Customer configurable panic */ 1906 xfs_cmn_err(XFS_PTAG_LOGRES, CE_ALERT, log->l_mp, 1907 "xfs_log_write: reservation ran out. Need to up reservation"); 1908 1909 /* If we did not panic, shutdown the filesystem */ 1910 xfs_force_shutdown(log->l_mp, SHUTDOWN_CORRUPT_INCORE); 1911 #endif 1912 } 1913 1914 ticket->t_curr_res -= len; 1915 1916 index = 0; 1917 lv = log_vector; 1918 vecp = lv->lv_iovecp; 1919 while (lv && index < lv->lv_niovecs) { 1920 __psint_t ptr; 1921 int log_offset; 1922 1923 error = xlog_state_get_iclog_space(log, len, &iclog, ticket, 1924 &contwr, &log_offset); 1925 if (error) 1926 return error; 1927 1928 ASSERT(log_offset <= iclog->ic_size - 1); 1929 ptr = (__psint_t)((char *)iclog->ic_datap + log_offset); 1930 1931 /* start_lsn is the first lsn written to. That's all we need. */ 1932 if (!*start_lsn) 1933 *start_lsn = be64_to_cpu(iclog->ic_header.h_lsn); 1934 1935 /* 1936 * This loop writes out as many regions as can fit in the amount 1937 * of space which was allocated by xlog_state_get_iclog_space(). 1938 */ 1939 while (lv && index < lv->lv_niovecs) { 1940 struct xfs_log_iovec *reg = &vecp[index]; 1941 struct xlog_op_header *ophdr; 1942 int start_rec_copy; 1943 int copy_len; 1944 int copy_off; 1945 1946 ASSERT(reg->i_len % sizeof(__int32_t) == 0); 1947 ASSERT((__psint_t)ptr % sizeof(__int32_t) == 0); 1948 1949 start_rec_copy = xlog_write_start_rec(ptr, ticket); 1950 if (start_rec_copy) { 1951 record_cnt++; 1952 xlog_write_adv_cnt(ptr, len, log_offset, 1953 start_rec_copy); 1954 } 1955 1956 ophdr = xlog_write_setup_ophdr(log, ptr, ticket, flags); 1957 if (!ophdr) 1958 return XFS_ERROR(EIO); 1959 1960 xlog_write_adv_cnt(ptr, len, log_offset, 1961 sizeof(struct xlog_op_header)); 1962 1963 len += xlog_write_setup_copy(ticket, ophdr, 1964 iclog->ic_size-log_offset, 1965 reg->i_len, 1966 ©_off, ©_len, 1967 &partial_copy, 1968 &partial_copy_len); 1969 xlog_verify_dest_ptr(log, ptr); 1970 1971 /* copy region */ 1972 ASSERT(copy_len >= 0); 1973 memcpy((xfs_caddr_t)ptr, reg->i_addr + copy_off, 1974 copy_len); 1975 xlog_write_adv_cnt(ptr, len, log_offset, copy_len); 1976 1977 copy_len += start_rec_copy + sizeof(xlog_op_header_t); 1978 record_cnt++; 1979 data_cnt += contwr ? copy_len : 0; 1980 1981 error = xlog_write_copy_finish(log, iclog, flags, 1982 &record_cnt, &data_cnt, 1983 &partial_copy, 1984 &partial_copy_len, 1985 log_offset, 1986 commit_iclog); 1987 if (error) 1988 return error; 1989 1990 /* 1991 * if we had a partial copy, we need to get more iclog 1992 * space but we don't want to increment the region 1993 * index because there is still more is this region to 1994 * write. 1995 * 1996 * If we completed writing this region, and we flushed 1997 * the iclog (indicated by resetting of the record 1998 * count), then we also need to get more log space. If 1999 * this was the last record, though, we are done and 2000 * can just return. 2001 */ 2002 if (partial_copy) 2003 break; 2004 2005 if (++index == lv->lv_niovecs) { 2006 lv = lv->lv_next; 2007 index = 0; 2008 if (lv) 2009 vecp = lv->lv_iovecp; 2010 } 2011 if (record_cnt == 0) { 2012 if (!lv) 2013 return 0; 2014 break; 2015 } 2016 } 2017 } 2018 2019 ASSERT(len == 0); 2020 2021 xlog_state_finish_copy(log, iclog, record_cnt, data_cnt); 2022 if (!commit_iclog) 2023 return xlog_state_release_iclog(log, iclog); 2024 2025 ASSERT(flags & XLOG_COMMIT_TRANS); 2026 *commit_iclog = iclog; 2027 return 0; 2028 } 2029 2030 2031 /***************************************************************************** 2032 * 2033 * State Machine functions 2034 * 2035 ***************************************************************************** 2036 */ 2037 2038 /* Clean iclogs starting from the head. This ordering must be 2039 * maintained, so an iclog doesn't become ACTIVE beyond one that 2040 * is SYNCING. This is also required to maintain the notion that we use 2041 * a ordered wait queue to hold off would be writers to the log when every 2042 * iclog is trying to sync to disk. 2043 * 2044 * State Change: DIRTY -> ACTIVE 2045 */ 2046 STATIC void 2047 xlog_state_clean_log(xlog_t *log) 2048 { 2049 xlog_in_core_t *iclog; 2050 int changed = 0; 2051 2052 iclog = log->l_iclog; 2053 do { 2054 if (iclog->ic_state == XLOG_STATE_DIRTY) { 2055 iclog->ic_state = XLOG_STATE_ACTIVE; 2056 iclog->ic_offset = 0; 2057 ASSERT(iclog->ic_callback == NULL); 2058 /* 2059 * If the number of ops in this iclog indicate it just 2060 * contains the dummy transaction, we can 2061 * change state into IDLE (the second time around). 2062 * Otherwise we should change the state into 2063 * NEED a dummy. 2064 * We don't need to cover the dummy. 2065 */ 2066 if (!changed && 2067 (be32_to_cpu(iclog->ic_header.h_num_logops) == 2068 XLOG_COVER_OPS)) { 2069 changed = 1; 2070 } else { 2071 /* 2072 * We have two dirty iclogs so start over 2073 * This could also be num of ops indicates 2074 * this is not the dummy going out. 2075 */ 2076 changed = 2; 2077 } 2078 iclog->ic_header.h_num_logops = 0; 2079 memset(iclog->ic_header.h_cycle_data, 0, 2080 sizeof(iclog->ic_header.h_cycle_data)); 2081 iclog->ic_header.h_lsn = 0; 2082 } else if (iclog->ic_state == XLOG_STATE_ACTIVE) 2083 /* do nothing */; 2084 else 2085 break; /* stop cleaning */ 2086 iclog = iclog->ic_next; 2087 } while (iclog != log->l_iclog); 2088 2089 /* log is locked when we are called */ 2090 /* 2091 * Change state for the dummy log recording. 2092 * We usually go to NEED. But we go to NEED2 if the changed indicates 2093 * we are done writing the dummy record. 2094 * If we are done with the second dummy recored (DONE2), then 2095 * we go to IDLE. 2096 */ 2097 if (changed) { 2098 switch (log->l_covered_state) { 2099 case XLOG_STATE_COVER_IDLE: 2100 case XLOG_STATE_COVER_NEED: 2101 case XLOG_STATE_COVER_NEED2: 2102 log->l_covered_state = XLOG_STATE_COVER_NEED; 2103 break; 2104 2105 case XLOG_STATE_COVER_DONE: 2106 if (changed == 1) 2107 log->l_covered_state = XLOG_STATE_COVER_NEED2; 2108 else 2109 log->l_covered_state = XLOG_STATE_COVER_NEED; 2110 break; 2111 2112 case XLOG_STATE_COVER_DONE2: 2113 if (changed == 1) 2114 log->l_covered_state = XLOG_STATE_COVER_IDLE; 2115 else 2116 log->l_covered_state = XLOG_STATE_COVER_NEED; 2117 break; 2118 2119 default: 2120 ASSERT(0); 2121 } 2122 } 2123 } /* xlog_state_clean_log */ 2124 2125 STATIC xfs_lsn_t 2126 xlog_get_lowest_lsn( 2127 xlog_t *log) 2128 { 2129 xlog_in_core_t *lsn_log; 2130 xfs_lsn_t lowest_lsn, lsn; 2131 2132 lsn_log = log->l_iclog; 2133 lowest_lsn = 0; 2134 do { 2135 if (!(lsn_log->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_DIRTY))) { 2136 lsn = be64_to_cpu(lsn_log->ic_header.h_lsn); 2137 if ((lsn && !lowest_lsn) || 2138 (XFS_LSN_CMP(lsn, lowest_lsn) < 0)) { 2139 lowest_lsn = lsn; 2140 } 2141 } 2142 lsn_log = lsn_log->ic_next; 2143 } while (lsn_log != log->l_iclog); 2144 return lowest_lsn; 2145 } 2146 2147 2148 STATIC void 2149 xlog_state_do_callback( 2150 xlog_t *log, 2151 int aborted, 2152 xlog_in_core_t *ciclog) 2153 { 2154 xlog_in_core_t *iclog; 2155 xlog_in_core_t *first_iclog; /* used to know when we've 2156 * processed all iclogs once */ 2157 xfs_log_callback_t *cb, *cb_next; 2158 int flushcnt = 0; 2159 xfs_lsn_t lowest_lsn; 2160 int ioerrors; /* counter: iclogs with errors */ 2161 int loopdidcallbacks; /* flag: inner loop did callbacks*/ 2162 int funcdidcallbacks; /* flag: function did callbacks */ 2163 int repeats; /* for issuing console warnings if 2164 * looping too many times */ 2165 int wake = 0; 2166 2167 spin_lock(&log->l_icloglock); 2168 first_iclog = iclog = log->l_iclog; 2169 ioerrors = 0; 2170 funcdidcallbacks = 0; 2171 repeats = 0; 2172 2173 do { 2174 /* 2175 * Scan all iclogs starting with the one pointed to by the 2176 * log. Reset this starting point each time the log is 2177 * unlocked (during callbacks). 2178 * 2179 * Keep looping through iclogs until one full pass is made 2180 * without running any callbacks. 2181 */ 2182 first_iclog = log->l_iclog; 2183 iclog = log->l_iclog; 2184 loopdidcallbacks = 0; 2185 repeats++; 2186 2187 do { 2188 2189 /* skip all iclogs in the ACTIVE & DIRTY states */ 2190 if (iclog->ic_state & 2191 (XLOG_STATE_ACTIVE|XLOG_STATE_DIRTY)) { 2192 iclog = iclog->ic_next; 2193 continue; 2194 } 2195 2196 /* 2197 * Between marking a filesystem SHUTDOWN and stopping 2198 * the log, we do flush all iclogs to disk (if there 2199 * wasn't a log I/O error). So, we do want things to 2200 * go smoothly in case of just a SHUTDOWN w/o a 2201 * LOG_IO_ERROR. 2202 */ 2203 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) { 2204 /* 2205 * Can only perform callbacks in order. Since 2206 * this iclog is not in the DONE_SYNC/ 2207 * DO_CALLBACK state, we skip the rest and 2208 * just try to clean up. If we set our iclog 2209 * to DO_CALLBACK, we will not process it when 2210 * we retry since a previous iclog is in the 2211 * CALLBACK and the state cannot change since 2212 * we are holding the l_icloglock. 2213 */ 2214 if (!(iclog->ic_state & 2215 (XLOG_STATE_DONE_SYNC | 2216 XLOG_STATE_DO_CALLBACK))) { 2217 if (ciclog && (ciclog->ic_state == 2218 XLOG_STATE_DONE_SYNC)) { 2219 ciclog->ic_state = XLOG_STATE_DO_CALLBACK; 2220 } 2221 break; 2222 } 2223 /* 2224 * We now have an iclog that is in either the 2225 * DO_CALLBACK or DONE_SYNC states. The other 2226 * states (WANT_SYNC, SYNCING, or CALLBACK were 2227 * caught by the above if and are going to 2228 * clean (i.e. we aren't doing their callbacks) 2229 * see the above if. 2230 */ 2231 2232 /* 2233 * We will do one more check here to see if we 2234 * have chased our tail around. 2235 */ 2236 2237 lowest_lsn = xlog_get_lowest_lsn(log); 2238 if (lowest_lsn && 2239 XFS_LSN_CMP(lowest_lsn, 2240 be64_to_cpu(iclog->ic_header.h_lsn)) < 0) { 2241 iclog = iclog->ic_next; 2242 continue; /* Leave this iclog for 2243 * another thread */ 2244 } 2245 2246 iclog->ic_state = XLOG_STATE_CALLBACK; 2247 2248 spin_unlock(&log->l_icloglock); 2249 2250 /* l_last_sync_lsn field protected by 2251 * l_grant_lock. Don't worry about iclog's lsn. 2252 * No one else can be here except us. 2253 */ 2254 spin_lock(&log->l_grant_lock); 2255 ASSERT(XFS_LSN_CMP(log->l_last_sync_lsn, 2256 be64_to_cpu(iclog->ic_header.h_lsn)) <= 0); 2257 log->l_last_sync_lsn = 2258 be64_to_cpu(iclog->ic_header.h_lsn); 2259 spin_unlock(&log->l_grant_lock); 2260 2261 } else { 2262 spin_unlock(&log->l_icloglock); 2263 ioerrors++; 2264 } 2265 2266 /* 2267 * Keep processing entries in the callback list until 2268 * we come around and it is empty. We need to 2269 * atomically see that the list is empty and change the 2270 * state to DIRTY so that we don't miss any more 2271 * callbacks being added. 2272 */ 2273 spin_lock(&iclog->ic_callback_lock); 2274 cb = iclog->ic_callback; 2275 while (cb) { 2276 iclog->ic_callback_tail = &(iclog->ic_callback); 2277 iclog->ic_callback = NULL; 2278 spin_unlock(&iclog->ic_callback_lock); 2279 2280 /* perform callbacks in the order given */ 2281 for (; cb; cb = cb_next) { 2282 cb_next = cb->cb_next; 2283 cb->cb_func(cb->cb_arg, aborted); 2284 } 2285 spin_lock(&iclog->ic_callback_lock); 2286 cb = iclog->ic_callback; 2287 } 2288 2289 loopdidcallbacks++; 2290 funcdidcallbacks++; 2291 2292 spin_lock(&log->l_icloglock); 2293 ASSERT(iclog->ic_callback == NULL); 2294 spin_unlock(&iclog->ic_callback_lock); 2295 if (!(iclog->ic_state & XLOG_STATE_IOERROR)) 2296 iclog->ic_state = XLOG_STATE_DIRTY; 2297 2298 /* 2299 * Transition from DIRTY to ACTIVE if applicable. 2300 * NOP if STATE_IOERROR. 2301 */ 2302 xlog_state_clean_log(log); 2303 2304 /* wake up threads waiting in xfs_log_force() */ 2305 sv_broadcast(&iclog->ic_force_wait); 2306 2307 iclog = iclog->ic_next; 2308 } while (first_iclog != iclog); 2309 2310 if (repeats > 5000) { 2311 flushcnt += repeats; 2312 repeats = 0; 2313 xfs_fs_cmn_err(CE_WARN, log->l_mp, 2314 "%s: possible infinite loop (%d iterations)", 2315 __func__, flushcnt); 2316 } 2317 } while (!ioerrors && loopdidcallbacks); 2318 2319 /* 2320 * make one last gasp attempt to see if iclogs are being left in 2321 * limbo.. 2322 */ 2323 #ifdef DEBUG 2324 if (funcdidcallbacks) { 2325 first_iclog = iclog = log->l_iclog; 2326 do { 2327 ASSERT(iclog->ic_state != XLOG_STATE_DO_CALLBACK); 2328 /* 2329 * Terminate the loop if iclogs are found in states 2330 * which will cause other threads to clean up iclogs. 2331 * 2332 * SYNCING - i/o completion will go through logs 2333 * DONE_SYNC - interrupt thread should be waiting for 2334 * l_icloglock 2335 * IOERROR - give up hope all ye who enter here 2336 */ 2337 if (iclog->ic_state == XLOG_STATE_WANT_SYNC || 2338 iclog->ic_state == XLOG_STATE_SYNCING || 2339 iclog->ic_state == XLOG_STATE_DONE_SYNC || 2340 iclog->ic_state == XLOG_STATE_IOERROR ) 2341 break; 2342 iclog = iclog->ic_next; 2343 } while (first_iclog != iclog); 2344 } 2345 #endif 2346 2347 if (log->l_iclog->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_IOERROR)) 2348 wake = 1; 2349 spin_unlock(&log->l_icloglock); 2350 2351 if (wake) 2352 sv_broadcast(&log->l_flush_wait); 2353 } 2354 2355 2356 /* 2357 * Finish transitioning this iclog to the dirty state. 2358 * 2359 * Make sure that we completely execute this routine only when this is 2360 * the last call to the iclog. There is a good chance that iclog flushes, 2361 * when we reach the end of the physical log, get turned into 2 separate 2362 * calls to bwrite. Hence, one iclog flush could generate two calls to this 2363 * routine. By using the reference count bwritecnt, we guarantee that only 2364 * the second completion goes through. 2365 * 2366 * Callbacks could take time, so they are done outside the scope of the 2367 * global state machine log lock. 2368 */ 2369 STATIC void 2370 xlog_state_done_syncing( 2371 xlog_in_core_t *iclog, 2372 int aborted) 2373 { 2374 xlog_t *log = iclog->ic_log; 2375 2376 spin_lock(&log->l_icloglock); 2377 2378 ASSERT(iclog->ic_state == XLOG_STATE_SYNCING || 2379 iclog->ic_state == XLOG_STATE_IOERROR); 2380 ASSERT(atomic_read(&iclog->ic_refcnt) == 0); 2381 ASSERT(iclog->ic_bwritecnt == 1 || iclog->ic_bwritecnt == 2); 2382 2383 2384 /* 2385 * If we got an error, either on the first buffer, or in the case of 2386 * split log writes, on the second, we mark ALL iclogs STATE_IOERROR, 2387 * and none should ever be attempted to be written to disk 2388 * again. 2389 */ 2390 if (iclog->ic_state != XLOG_STATE_IOERROR) { 2391 if (--iclog->ic_bwritecnt == 1) { 2392 spin_unlock(&log->l_icloglock); 2393 return; 2394 } 2395 iclog->ic_state = XLOG_STATE_DONE_SYNC; 2396 } 2397 2398 /* 2399 * Someone could be sleeping prior to writing out the next 2400 * iclog buffer, we wake them all, one will get to do the 2401 * I/O, the others get to wait for the result. 2402 */ 2403 sv_broadcast(&iclog->ic_write_wait); 2404 spin_unlock(&log->l_icloglock); 2405 xlog_state_do_callback(log, aborted, iclog); /* also cleans log */ 2406 } /* xlog_state_done_syncing */ 2407 2408 2409 /* 2410 * If the head of the in-core log ring is not (ACTIVE or DIRTY), then we must 2411 * sleep. We wait on the flush queue on the head iclog as that should be 2412 * the first iclog to complete flushing. Hence if all iclogs are syncing, 2413 * we will wait here and all new writes will sleep until a sync completes. 2414 * 2415 * The in-core logs are used in a circular fashion. They are not used 2416 * out-of-order even when an iclog past the head is free. 2417 * 2418 * return: 2419 * * log_offset where xlog_write() can start writing into the in-core 2420 * log's data space. 2421 * * in-core log pointer to which xlog_write() should write. 2422 * * boolean indicating this is a continued write to an in-core log. 2423 * If this is the last write, then the in-core log's offset field 2424 * needs to be incremented, depending on the amount of data which 2425 * is copied. 2426 */ 2427 STATIC int 2428 xlog_state_get_iclog_space(xlog_t *log, 2429 int len, 2430 xlog_in_core_t **iclogp, 2431 xlog_ticket_t *ticket, 2432 int *continued_write, 2433 int *logoffsetp) 2434 { 2435 int log_offset; 2436 xlog_rec_header_t *head; 2437 xlog_in_core_t *iclog; 2438 int error; 2439 2440 restart: 2441 spin_lock(&log->l_icloglock); 2442 if (XLOG_FORCED_SHUTDOWN(log)) { 2443 spin_unlock(&log->l_icloglock); 2444 return XFS_ERROR(EIO); 2445 } 2446 2447 iclog = log->l_iclog; 2448 if (iclog->ic_state != XLOG_STATE_ACTIVE) { 2449 XFS_STATS_INC(xs_log_noiclogs); 2450 2451 /* Wait for log writes to have flushed */ 2452 sv_wait(&log->l_flush_wait, 0, &log->l_icloglock, 0); 2453 goto restart; 2454 } 2455 2456 head = &iclog->ic_header; 2457 2458 atomic_inc(&iclog->ic_refcnt); /* prevents sync */ 2459 log_offset = iclog->ic_offset; 2460 2461 /* On the 1st write to an iclog, figure out lsn. This works 2462 * if iclogs marked XLOG_STATE_WANT_SYNC always write out what they are 2463 * committing to. If the offset is set, that's how many blocks 2464 * must be written. 2465 */ 2466 if (log_offset == 0) { 2467 ticket->t_curr_res -= log->l_iclog_hsize; 2468 xlog_tic_add_region(ticket, 2469 log->l_iclog_hsize, 2470 XLOG_REG_TYPE_LRHEADER); 2471 head->h_cycle = cpu_to_be32(log->l_curr_cycle); 2472 head->h_lsn = cpu_to_be64( 2473 xlog_assign_lsn(log->l_curr_cycle, log->l_curr_block)); 2474 ASSERT(log->l_curr_block >= 0); 2475 } 2476 2477 /* If there is enough room to write everything, then do it. Otherwise, 2478 * claim the rest of the region and make sure the XLOG_STATE_WANT_SYNC 2479 * bit is on, so this will get flushed out. Don't update ic_offset 2480 * until you know exactly how many bytes get copied. Therefore, wait 2481 * until later to update ic_offset. 2482 * 2483 * xlog_write() algorithm assumes that at least 2 xlog_op_header_t's 2484 * can fit into remaining data section. 2485 */ 2486 if (iclog->ic_size - iclog->ic_offset < 2*sizeof(xlog_op_header_t)) { 2487 xlog_state_switch_iclogs(log, iclog, iclog->ic_size); 2488 2489 /* 2490 * If I'm the only one writing to this iclog, sync it to disk. 2491 * We need to do an atomic compare and decrement here to avoid 2492 * racing with concurrent atomic_dec_and_lock() calls in 2493 * xlog_state_release_iclog() when there is more than one 2494 * reference to the iclog. 2495 */ 2496 if (!atomic_add_unless(&iclog->ic_refcnt, -1, 1)) { 2497 /* we are the only one */ 2498 spin_unlock(&log->l_icloglock); 2499 error = xlog_state_release_iclog(log, iclog); 2500 if (error) 2501 return error; 2502 } else { 2503 spin_unlock(&log->l_icloglock); 2504 } 2505 goto restart; 2506 } 2507 2508 /* Do we have enough room to write the full amount in the remainder 2509 * of this iclog? Or must we continue a write on the next iclog and 2510 * mark this iclog as completely taken? In the case where we switch 2511 * iclogs (to mark it taken), this particular iclog will release/sync 2512 * to disk in xlog_write(). 2513 */ 2514 if (len <= iclog->ic_size - iclog->ic_offset) { 2515 *continued_write = 0; 2516 iclog->ic_offset += len; 2517 } else { 2518 *continued_write = 1; 2519 xlog_state_switch_iclogs(log, iclog, iclog->ic_size); 2520 } 2521 *iclogp = iclog; 2522 2523 ASSERT(iclog->ic_offset <= iclog->ic_size); 2524 spin_unlock(&log->l_icloglock); 2525 2526 *logoffsetp = log_offset; 2527 return 0; 2528 } /* xlog_state_get_iclog_space */ 2529 2530 /* 2531 * Atomically get the log space required for a log ticket. 2532 * 2533 * Once a ticket gets put onto the reserveq, it will only return after 2534 * the needed reservation is satisfied. 2535 */ 2536 STATIC int 2537 xlog_grant_log_space(xlog_t *log, 2538 xlog_ticket_t *tic) 2539 { 2540 int free_bytes; 2541 int need_bytes; 2542 #ifdef DEBUG 2543 xfs_lsn_t tail_lsn; 2544 #endif 2545 2546 2547 #ifdef DEBUG 2548 if (log->l_flags & XLOG_ACTIVE_RECOVERY) 2549 panic("grant Recovery problem"); 2550 #endif 2551 2552 /* Is there space or do we need to sleep? */ 2553 spin_lock(&log->l_grant_lock); 2554 2555 trace_xfs_log_grant_enter(log, tic); 2556 2557 /* something is already sleeping; insert new transaction at end */ 2558 if (log->l_reserve_headq) { 2559 xlog_ins_ticketq(&log->l_reserve_headq, tic); 2560 2561 trace_xfs_log_grant_sleep1(log, tic); 2562 2563 /* 2564 * Gotta check this before going to sleep, while we're 2565 * holding the grant lock. 2566 */ 2567 if (XLOG_FORCED_SHUTDOWN(log)) 2568 goto error_return; 2569 2570 XFS_STATS_INC(xs_sleep_logspace); 2571 sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s); 2572 /* 2573 * If we got an error, and the filesystem is shutting down, 2574 * we'll catch it down below. So just continue... 2575 */ 2576 trace_xfs_log_grant_wake1(log, tic); 2577 spin_lock(&log->l_grant_lock); 2578 } 2579 if (tic->t_flags & XFS_LOG_PERM_RESERV) 2580 need_bytes = tic->t_unit_res*tic->t_ocnt; 2581 else 2582 need_bytes = tic->t_unit_res; 2583 2584 redo: 2585 if (XLOG_FORCED_SHUTDOWN(log)) 2586 goto error_return; 2587 2588 free_bytes = xlog_space_left(log, log->l_grant_reserve_cycle, 2589 log->l_grant_reserve_bytes); 2590 if (free_bytes < need_bytes) { 2591 if ((tic->t_flags & XLOG_TIC_IN_Q) == 0) 2592 xlog_ins_ticketq(&log->l_reserve_headq, tic); 2593 2594 trace_xfs_log_grant_sleep2(log, tic); 2595 2596 spin_unlock(&log->l_grant_lock); 2597 xlog_grant_push_ail(log->l_mp, need_bytes); 2598 spin_lock(&log->l_grant_lock); 2599 2600 XFS_STATS_INC(xs_sleep_logspace); 2601 sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s); 2602 2603 spin_lock(&log->l_grant_lock); 2604 if (XLOG_FORCED_SHUTDOWN(log)) 2605 goto error_return; 2606 2607 trace_xfs_log_grant_wake2(log, tic); 2608 2609 goto redo; 2610 } else if (tic->t_flags & XLOG_TIC_IN_Q) 2611 xlog_del_ticketq(&log->l_reserve_headq, tic); 2612 2613 /* we've got enough space */ 2614 xlog_grant_add_space(log, need_bytes); 2615 #ifdef DEBUG 2616 tail_lsn = log->l_tail_lsn; 2617 /* 2618 * Check to make sure the grant write head didn't just over lap the 2619 * tail. If the cycles are the same, we can't be overlapping. 2620 * Otherwise, make sure that the cycles differ by exactly one and 2621 * check the byte count. 2622 */ 2623 if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) { 2624 ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn)); 2625 ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn))); 2626 } 2627 #endif 2628 trace_xfs_log_grant_exit(log, tic); 2629 xlog_verify_grant_head(log, 1); 2630 spin_unlock(&log->l_grant_lock); 2631 return 0; 2632 2633 error_return: 2634 if (tic->t_flags & XLOG_TIC_IN_Q) 2635 xlog_del_ticketq(&log->l_reserve_headq, tic); 2636 2637 trace_xfs_log_grant_error(log, tic); 2638 2639 /* 2640 * If we are failing, make sure the ticket doesn't have any 2641 * current reservations. We don't want to add this back when 2642 * the ticket/transaction gets cancelled. 2643 */ 2644 tic->t_curr_res = 0; 2645 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */ 2646 spin_unlock(&log->l_grant_lock); 2647 return XFS_ERROR(EIO); 2648 } /* xlog_grant_log_space */ 2649 2650 2651 /* 2652 * Replenish the byte reservation required by moving the grant write head. 2653 * 2654 * 2655 */ 2656 STATIC int 2657 xlog_regrant_write_log_space(xlog_t *log, 2658 xlog_ticket_t *tic) 2659 { 2660 int free_bytes, need_bytes; 2661 xlog_ticket_t *ntic; 2662 #ifdef DEBUG 2663 xfs_lsn_t tail_lsn; 2664 #endif 2665 2666 tic->t_curr_res = tic->t_unit_res; 2667 xlog_tic_reset_res(tic); 2668 2669 if (tic->t_cnt > 0) 2670 return 0; 2671 2672 #ifdef DEBUG 2673 if (log->l_flags & XLOG_ACTIVE_RECOVERY) 2674 panic("regrant Recovery problem"); 2675 #endif 2676 2677 spin_lock(&log->l_grant_lock); 2678 2679 trace_xfs_log_regrant_write_enter(log, tic); 2680 2681 if (XLOG_FORCED_SHUTDOWN(log)) 2682 goto error_return; 2683 2684 /* If there are other waiters on the queue then give them a 2685 * chance at logspace before us. Wake up the first waiters, 2686 * if we do not wake up all the waiters then go to sleep waiting 2687 * for more free space, otherwise try to get some space for 2688 * this transaction. 2689 */ 2690 need_bytes = tic->t_unit_res; 2691 if ((ntic = log->l_write_headq)) { 2692 free_bytes = xlog_space_left(log, log->l_grant_write_cycle, 2693 log->l_grant_write_bytes); 2694 do { 2695 ASSERT(ntic->t_flags & XLOG_TIC_PERM_RESERV); 2696 2697 if (free_bytes < ntic->t_unit_res) 2698 break; 2699 free_bytes -= ntic->t_unit_res; 2700 sv_signal(&ntic->t_wait); 2701 ntic = ntic->t_next; 2702 } while (ntic != log->l_write_headq); 2703 2704 if (ntic != log->l_write_headq) { 2705 if ((tic->t_flags & XLOG_TIC_IN_Q) == 0) 2706 xlog_ins_ticketq(&log->l_write_headq, tic); 2707 2708 trace_xfs_log_regrant_write_sleep1(log, tic); 2709 2710 spin_unlock(&log->l_grant_lock); 2711 xlog_grant_push_ail(log->l_mp, need_bytes); 2712 spin_lock(&log->l_grant_lock); 2713 2714 XFS_STATS_INC(xs_sleep_logspace); 2715 sv_wait(&tic->t_wait, PINOD|PLTWAIT, 2716 &log->l_grant_lock, s); 2717 2718 /* If we're shutting down, this tic is already 2719 * off the queue */ 2720 spin_lock(&log->l_grant_lock); 2721 if (XLOG_FORCED_SHUTDOWN(log)) 2722 goto error_return; 2723 2724 trace_xfs_log_regrant_write_wake1(log, tic); 2725 } 2726 } 2727 2728 redo: 2729 if (XLOG_FORCED_SHUTDOWN(log)) 2730 goto error_return; 2731 2732 free_bytes = xlog_space_left(log, log->l_grant_write_cycle, 2733 log->l_grant_write_bytes); 2734 if (free_bytes < need_bytes) { 2735 if ((tic->t_flags & XLOG_TIC_IN_Q) == 0) 2736 xlog_ins_ticketq(&log->l_write_headq, tic); 2737 spin_unlock(&log->l_grant_lock); 2738 xlog_grant_push_ail(log->l_mp, need_bytes); 2739 spin_lock(&log->l_grant_lock); 2740 2741 XFS_STATS_INC(xs_sleep_logspace); 2742 trace_xfs_log_regrant_write_sleep2(log, tic); 2743 2744 sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s); 2745 2746 /* If we're shutting down, this tic is already off the queue */ 2747 spin_lock(&log->l_grant_lock); 2748 if (XLOG_FORCED_SHUTDOWN(log)) 2749 goto error_return; 2750 2751 trace_xfs_log_regrant_write_wake2(log, tic); 2752 goto redo; 2753 } else if (tic->t_flags & XLOG_TIC_IN_Q) 2754 xlog_del_ticketq(&log->l_write_headq, tic); 2755 2756 /* we've got enough space */ 2757 xlog_grant_add_space_write(log, need_bytes); 2758 #ifdef DEBUG 2759 tail_lsn = log->l_tail_lsn; 2760 if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) { 2761 ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn)); 2762 ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn))); 2763 } 2764 #endif 2765 2766 trace_xfs_log_regrant_write_exit(log, tic); 2767 2768 xlog_verify_grant_head(log, 1); 2769 spin_unlock(&log->l_grant_lock); 2770 return 0; 2771 2772 2773 error_return: 2774 if (tic->t_flags & XLOG_TIC_IN_Q) 2775 xlog_del_ticketq(&log->l_reserve_headq, tic); 2776 2777 trace_xfs_log_regrant_write_error(log, tic); 2778 2779 /* 2780 * If we are failing, make sure the ticket doesn't have any 2781 * current reservations. We don't want to add this back when 2782 * the ticket/transaction gets cancelled. 2783 */ 2784 tic->t_curr_res = 0; 2785 tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */ 2786 spin_unlock(&log->l_grant_lock); 2787 return XFS_ERROR(EIO); 2788 } /* xlog_regrant_write_log_space */ 2789 2790 2791 /* The first cnt-1 times through here we don't need to 2792 * move the grant write head because the permanent 2793 * reservation has reserved cnt times the unit amount. 2794 * Release part of current permanent unit reservation and 2795 * reset current reservation to be one units worth. Also 2796 * move grant reservation head forward. 2797 */ 2798 STATIC void 2799 xlog_regrant_reserve_log_space(xlog_t *log, 2800 xlog_ticket_t *ticket) 2801 { 2802 trace_xfs_log_regrant_reserve_enter(log, ticket); 2803 2804 if (ticket->t_cnt > 0) 2805 ticket->t_cnt--; 2806 2807 spin_lock(&log->l_grant_lock); 2808 xlog_grant_sub_space(log, ticket->t_curr_res); 2809 ticket->t_curr_res = ticket->t_unit_res; 2810 xlog_tic_reset_res(ticket); 2811 2812 trace_xfs_log_regrant_reserve_sub(log, ticket); 2813 2814 xlog_verify_grant_head(log, 1); 2815 2816 /* just return if we still have some of the pre-reserved space */ 2817 if (ticket->t_cnt > 0) { 2818 spin_unlock(&log->l_grant_lock); 2819 return; 2820 } 2821 2822 xlog_grant_add_space_reserve(log, ticket->t_unit_res); 2823 2824 trace_xfs_log_regrant_reserve_exit(log, ticket); 2825 2826 xlog_verify_grant_head(log, 0); 2827 spin_unlock(&log->l_grant_lock); 2828 ticket->t_curr_res = ticket->t_unit_res; 2829 xlog_tic_reset_res(ticket); 2830 } /* xlog_regrant_reserve_log_space */ 2831 2832 2833 /* 2834 * Give back the space left from a reservation. 2835 * 2836 * All the information we need to make a correct determination of space left 2837 * is present. For non-permanent reservations, things are quite easy. The 2838 * count should have been decremented to zero. We only need to deal with the 2839 * space remaining in the current reservation part of the ticket. If the 2840 * ticket contains a permanent reservation, there may be left over space which 2841 * needs to be released. A count of N means that N-1 refills of the current 2842 * reservation can be done before we need to ask for more space. The first 2843 * one goes to fill up the first current reservation. Once we run out of 2844 * space, the count will stay at zero and the only space remaining will be 2845 * in the current reservation field. 2846 */ 2847 STATIC void 2848 xlog_ungrant_log_space(xlog_t *log, 2849 xlog_ticket_t *ticket) 2850 { 2851 if (ticket->t_cnt > 0) 2852 ticket->t_cnt--; 2853 2854 spin_lock(&log->l_grant_lock); 2855 trace_xfs_log_ungrant_enter(log, ticket); 2856 2857 xlog_grant_sub_space(log, ticket->t_curr_res); 2858 2859 trace_xfs_log_ungrant_sub(log, ticket); 2860 2861 /* If this is a permanent reservation ticket, we may be able to free 2862 * up more space based on the remaining count. 2863 */ 2864 if (ticket->t_cnt > 0) { 2865 ASSERT(ticket->t_flags & XLOG_TIC_PERM_RESERV); 2866 xlog_grant_sub_space(log, ticket->t_unit_res*ticket->t_cnt); 2867 } 2868 2869 trace_xfs_log_ungrant_exit(log, ticket); 2870 2871 xlog_verify_grant_head(log, 1); 2872 spin_unlock(&log->l_grant_lock); 2873 xfs_log_move_tail(log->l_mp, 1); 2874 } /* xlog_ungrant_log_space */ 2875 2876 2877 /* 2878 * Flush iclog to disk if this is the last reference to the given iclog and 2879 * the WANT_SYNC bit is set. 2880 * 2881 * When this function is entered, the iclog is not necessarily in the 2882 * WANT_SYNC state. It may be sitting around waiting to get filled. 2883 * 2884 * 2885 */ 2886 STATIC int 2887 xlog_state_release_iclog( 2888 xlog_t *log, 2889 xlog_in_core_t *iclog) 2890 { 2891 int sync = 0; /* do we sync? */ 2892 2893 if (iclog->ic_state & XLOG_STATE_IOERROR) 2894 return XFS_ERROR(EIO); 2895 2896 ASSERT(atomic_read(&iclog->ic_refcnt) > 0); 2897 if (!atomic_dec_and_lock(&iclog->ic_refcnt, &log->l_icloglock)) 2898 return 0; 2899 2900 if (iclog->ic_state & XLOG_STATE_IOERROR) { 2901 spin_unlock(&log->l_icloglock); 2902 return XFS_ERROR(EIO); 2903 } 2904 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE || 2905 iclog->ic_state == XLOG_STATE_WANT_SYNC); 2906 2907 if (iclog->ic_state == XLOG_STATE_WANT_SYNC) { 2908 /* update tail before writing to iclog */ 2909 xlog_assign_tail_lsn(log->l_mp); 2910 sync++; 2911 iclog->ic_state = XLOG_STATE_SYNCING; 2912 iclog->ic_header.h_tail_lsn = cpu_to_be64(log->l_tail_lsn); 2913 xlog_verify_tail_lsn(log, iclog, log->l_tail_lsn); 2914 /* cycle incremented when incrementing curr_block */ 2915 } 2916 spin_unlock(&log->l_icloglock); 2917 2918 /* 2919 * We let the log lock go, so it's possible that we hit a log I/O 2920 * error or some other SHUTDOWN condition that marks the iclog 2921 * as XLOG_STATE_IOERROR before the bwrite. However, we know that 2922 * this iclog has consistent data, so we ignore IOERROR 2923 * flags after this point. 2924 */ 2925 if (sync) 2926 return xlog_sync(log, iclog); 2927 return 0; 2928 } /* xlog_state_release_iclog */ 2929 2930 2931 /* 2932 * This routine will mark the current iclog in the ring as WANT_SYNC 2933 * and move the current iclog pointer to the next iclog in the ring. 2934 * When this routine is called from xlog_state_get_iclog_space(), the 2935 * exact size of the iclog has not yet been determined. All we know is 2936 * that every data block. We have run out of space in this log record. 2937 */ 2938 STATIC void 2939 xlog_state_switch_iclogs(xlog_t *log, 2940 xlog_in_core_t *iclog, 2941 int eventual_size) 2942 { 2943 ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE); 2944 if (!eventual_size) 2945 eventual_size = iclog->ic_offset; 2946 iclog->ic_state = XLOG_STATE_WANT_SYNC; 2947 iclog->ic_header.h_prev_block = cpu_to_be32(log->l_prev_block); 2948 log->l_prev_block = log->l_curr_block; 2949 log->l_prev_cycle = log->l_curr_cycle; 2950 2951 /* roll log?: ic_offset changed later */ 2952 log->l_curr_block += BTOBB(eventual_size)+BTOBB(log->l_iclog_hsize); 2953 2954 /* Round up to next log-sunit */ 2955 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb) && 2956 log->l_mp->m_sb.sb_logsunit > 1) { 2957 __uint32_t sunit_bb = BTOBB(log->l_mp->m_sb.sb_logsunit); 2958 log->l_curr_block = roundup(log->l_curr_block, sunit_bb); 2959 } 2960 2961 if (log->l_curr_block >= log->l_logBBsize) { 2962 log->l_curr_cycle++; 2963 if (log->l_curr_cycle == XLOG_HEADER_MAGIC_NUM) 2964 log->l_curr_cycle++; 2965 log->l_curr_block -= log->l_logBBsize; 2966 ASSERT(log->l_curr_block >= 0); 2967 } 2968 ASSERT(iclog == log->l_iclog); 2969 log->l_iclog = iclog->ic_next; 2970 } /* xlog_state_switch_iclogs */ 2971 2972 /* 2973 * Write out all data in the in-core log as of this exact moment in time. 2974 * 2975 * Data may be written to the in-core log during this call. However, 2976 * we don't guarantee this data will be written out. A change from past 2977 * implementation means this routine will *not* write out zero length LRs. 2978 * 2979 * Basically, we try and perform an intelligent scan of the in-core logs. 2980 * If we determine there is no flushable data, we just return. There is no 2981 * flushable data if: 2982 * 2983 * 1. the current iclog is active and has no data; the previous iclog 2984 * is in the active or dirty state. 2985 * 2. the current iclog is drity, and the previous iclog is in the 2986 * active or dirty state. 2987 * 2988 * We may sleep if: 2989 * 2990 * 1. the current iclog is not in the active nor dirty state. 2991 * 2. the current iclog dirty, and the previous iclog is not in the 2992 * active nor dirty state. 2993 * 3. the current iclog is active, and there is another thread writing 2994 * to this particular iclog. 2995 * 4. a) the current iclog is active and has no other writers 2996 * b) when we return from flushing out this iclog, it is still 2997 * not in the active nor dirty state. 2998 */ 2999 int 3000 _xfs_log_force( 3001 struct xfs_mount *mp, 3002 uint flags, 3003 int *log_flushed) 3004 { 3005 struct log *log = mp->m_log; 3006 struct xlog_in_core *iclog; 3007 xfs_lsn_t lsn; 3008 3009 XFS_STATS_INC(xs_log_force); 3010 3011 spin_lock(&log->l_icloglock); 3012 3013 iclog = log->l_iclog; 3014 if (iclog->ic_state & XLOG_STATE_IOERROR) { 3015 spin_unlock(&log->l_icloglock); 3016 return XFS_ERROR(EIO); 3017 } 3018 3019 /* If the head iclog is not active nor dirty, we just attach 3020 * ourselves to the head and go to sleep. 3021 */ 3022 if (iclog->ic_state == XLOG_STATE_ACTIVE || 3023 iclog->ic_state == XLOG_STATE_DIRTY) { 3024 /* 3025 * If the head is dirty or (active and empty), then 3026 * we need to look at the previous iclog. If the previous 3027 * iclog is active or dirty we are done. There is nothing 3028 * to sync out. Otherwise, we attach ourselves to the 3029 * previous iclog and go to sleep. 3030 */ 3031 if (iclog->ic_state == XLOG_STATE_DIRTY || 3032 (atomic_read(&iclog->ic_refcnt) == 0 3033 && iclog->ic_offset == 0)) { 3034 iclog = iclog->ic_prev; 3035 if (iclog->ic_state == XLOG_STATE_ACTIVE || 3036 iclog->ic_state == XLOG_STATE_DIRTY) 3037 goto no_sleep; 3038 else 3039 goto maybe_sleep; 3040 } else { 3041 if (atomic_read(&iclog->ic_refcnt) == 0) { 3042 /* We are the only one with access to this 3043 * iclog. Flush it out now. There should 3044 * be a roundoff of zero to show that someone 3045 * has already taken care of the roundoff from 3046 * the previous sync. 3047 */ 3048 atomic_inc(&iclog->ic_refcnt); 3049 lsn = be64_to_cpu(iclog->ic_header.h_lsn); 3050 xlog_state_switch_iclogs(log, iclog, 0); 3051 spin_unlock(&log->l_icloglock); 3052 3053 if (xlog_state_release_iclog(log, iclog)) 3054 return XFS_ERROR(EIO); 3055 3056 if (log_flushed) 3057 *log_flushed = 1; 3058 spin_lock(&log->l_icloglock); 3059 if (be64_to_cpu(iclog->ic_header.h_lsn) == lsn && 3060 iclog->ic_state != XLOG_STATE_DIRTY) 3061 goto maybe_sleep; 3062 else 3063 goto no_sleep; 3064 } else { 3065 /* Someone else is writing to this iclog. 3066 * Use its call to flush out the data. However, 3067 * the other thread may not force out this LR, 3068 * so we mark it WANT_SYNC. 3069 */ 3070 xlog_state_switch_iclogs(log, iclog, 0); 3071 goto maybe_sleep; 3072 } 3073 } 3074 } 3075 3076 /* By the time we come around again, the iclog could've been filled 3077 * which would give it another lsn. If we have a new lsn, just 3078 * return because the relevant data has been flushed. 3079 */ 3080 maybe_sleep: 3081 if (flags & XFS_LOG_SYNC) { 3082 /* 3083 * We must check if we're shutting down here, before 3084 * we wait, while we're holding the l_icloglock. 3085 * Then we check again after waking up, in case our 3086 * sleep was disturbed by a bad news. 3087 */ 3088 if (iclog->ic_state & XLOG_STATE_IOERROR) { 3089 spin_unlock(&log->l_icloglock); 3090 return XFS_ERROR(EIO); 3091 } 3092 XFS_STATS_INC(xs_log_force_sleep); 3093 sv_wait(&iclog->ic_force_wait, PINOD, &log->l_icloglock, s); 3094 /* 3095 * No need to grab the log lock here since we're 3096 * only deciding whether or not to return EIO 3097 * and the memory read should be atomic. 3098 */ 3099 if (iclog->ic_state & XLOG_STATE_IOERROR) 3100 return XFS_ERROR(EIO); 3101 if (log_flushed) 3102 *log_flushed = 1; 3103 } else { 3104 3105 no_sleep: 3106 spin_unlock(&log->l_icloglock); 3107 } 3108 return 0; 3109 } 3110 3111 /* 3112 * Wrapper for _xfs_log_force(), to be used when caller doesn't care 3113 * about errors or whether the log was flushed or not. This is the normal 3114 * interface to use when trying to unpin items or move the log forward. 3115 */ 3116 void 3117 xfs_log_force( 3118 xfs_mount_t *mp, 3119 uint flags) 3120 { 3121 int error; 3122 3123 error = _xfs_log_force(mp, flags, NULL); 3124 if (error) { 3125 xfs_fs_cmn_err(CE_WARN, mp, "xfs_log_force: " 3126 "error %d returned.", error); 3127 } 3128 } 3129 3130 /* 3131 * Force the in-core log to disk for a specific LSN. 3132 * 3133 * Find in-core log with lsn. 3134 * If it is in the DIRTY state, just return. 3135 * If it is in the ACTIVE state, move the in-core log into the WANT_SYNC 3136 * state and go to sleep or return. 3137 * If it is in any other state, go to sleep or return. 3138 * 3139 * Synchronous forces are implemented with a signal variable. All callers 3140 * to force a given lsn to disk will wait on a the sv attached to the 3141 * specific in-core log. When given in-core log finally completes its 3142 * write to disk, that thread will wake up all threads waiting on the 3143 * sv. 3144 */ 3145 int 3146 _xfs_log_force_lsn( 3147 struct xfs_mount *mp, 3148 xfs_lsn_t lsn, 3149 uint flags, 3150 int *log_flushed) 3151 { 3152 struct log *log = mp->m_log; 3153 struct xlog_in_core *iclog; 3154 int already_slept = 0; 3155 3156 ASSERT(lsn != 0); 3157 3158 XFS_STATS_INC(xs_log_force); 3159 3160 try_again: 3161 spin_lock(&log->l_icloglock); 3162 iclog = log->l_iclog; 3163 if (iclog->ic_state & XLOG_STATE_IOERROR) { 3164 spin_unlock(&log->l_icloglock); 3165 return XFS_ERROR(EIO); 3166 } 3167 3168 do { 3169 if (be64_to_cpu(iclog->ic_header.h_lsn) != lsn) { 3170 iclog = iclog->ic_next; 3171 continue; 3172 } 3173 3174 if (iclog->ic_state == XLOG_STATE_DIRTY) { 3175 spin_unlock(&log->l_icloglock); 3176 return 0; 3177 } 3178 3179 if (iclog->ic_state == XLOG_STATE_ACTIVE) { 3180 /* 3181 * We sleep here if we haven't already slept (e.g. 3182 * this is the first time we've looked at the correct 3183 * iclog buf) and the buffer before us is going to 3184 * be sync'ed. The reason for this is that if we 3185 * are doing sync transactions here, by waiting for 3186 * the previous I/O to complete, we can allow a few 3187 * more transactions into this iclog before we close 3188 * it down. 3189 * 3190 * Otherwise, we mark the buffer WANT_SYNC, and bump 3191 * up the refcnt so we can release the log (which 3192 * drops the ref count). The state switch keeps new 3193 * transaction commits from using this buffer. When 3194 * the current commits finish writing into the buffer, 3195 * the refcount will drop to zero and the buffer will 3196 * go out then. 3197 */ 3198 if (!already_slept && 3199 (iclog->ic_prev->ic_state & 3200 (XLOG_STATE_WANT_SYNC | XLOG_STATE_SYNCING))) { 3201 ASSERT(!(iclog->ic_state & XLOG_STATE_IOERROR)); 3202 3203 XFS_STATS_INC(xs_log_force_sleep); 3204 3205 sv_wait(&iclog->ic_prev->ic_write_wait, 3206 PSWP, &log->l_icloglock, s); 3207 if (log_flushed) 3208 *log_flushed = 1; 3209 already_slept = 1; 3210 goto try_again; 3211 } 3212 atomic_inc(&iclog->ic_refcnt); 3213 xlog_state_switch_iclogs(log, iclog, 0); 3214 spin_unlock(&log->l_icloglock); 3215 if (xlog_state_release_iclog(log, iclog)) 3216 return XFS_ERROR(EIO); 3217 if (log_flushed) 3218 *log_flushed = 1; 3219 spin_lock(&log->l_icloglock); 3220 } 3221 3222 if ((flags & XFS_LOG_SYNC) && /* sleep */ 3223 !(iclog->ic_state & 3224 (XLOG_STATE_ACTIVE | XLOG_STATE_DIRTY))) { 3225 /* 3226 * Don't wait on completion if we know that we've 3227 * gotten a log write error. 3228 */ 3229 if (iclog->ic_state & XLOG_STATE_IOERROR) { 3230 spin_unlock(&log->l_icloglock); 3231 return XFS_ERROR(EIO); 3232 } 3233 XFS_STATS_INC(xs_log_force_sleep); 3234 sv_wait(&iclog->ic_force_wait, PSWP, &log->l_icloglock, s); 3235 /* 3236 * No need to grab the log lock here since we're 3237 * only deciding whether or not to return EIO 3238 * and the memory read should be atomic. 3239 */ 3240 if (iclog->ic_state & XLOG_STATE_IOERROR) 3241 return XFS_ERROR(EIO); 3242 3243 if (log_flushed) 3244 *log_flushed = 1; 3245 } else { /* just return */ 3246 spin_unlock(&log->l_icloglock); 3247 } 3248 3249 return 0; 3250 } while (iclog != log->l_iclog); 3251 3252 spin_unlock(&log->l_icloglock); 3253 return 0; 3254 } 3255 3256 /* 3257 * Wrapper for _xfs_log_force_lsn(), to be used when caller doesn't care 3258 * about errors or whether the log was flushed or not. This is the normal 3259 * interface to use when trying to unpin items or move the log forward. 3260 */ 3261 void 3262 xfs_log_force_lsn( 3263 xfs_mount_t *mp, 3264 xfs_lsn_t lsn, 3265 uint flags) 3266 { 3267 int error; 3268 3269 error = _xfs_log_force_lsn(mp, lsn, flags, NULL); 3270 if (error) { 3271 xfs_fs_cmn_err(CE_WARN, mp, "xfs_log_force: " 3272 "error %d returned.", error); 3273 } 3274 } 3275 3276 /* 3277 * Called when we want to mark the current iclog as being ready to sync to 3278 * disk. 3279 */ 3280 STATIC void 3281 xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog) 3282 { 3283 assert_spin_locked(&log->l_icloglock); 3284 3285 if (iclog->ic_state == XLOG_STATE_ACTIVE) { 3286 xlog_state_switch_iclogs(log, iclog, 0); 3287 } else { 3288 ASSERT(iclog->ic_state & 3289 (XLOG_STATE_WANT_SYNC|XLOG_STATE_IOERROR)); 3290 } 3291 } 3292 3293 3294 /***************************************************************************** 3295 * 3296 * TICKET functions 3297 * 3298 ***************************************************************************** 3299 */ 3300 3301 /* 3302 * Free a used ticket when its refcount falls to zero. 3303 */ 3304 void 3305 xfs_log_ticket_put( 3306 xlog_ticket_t *ticket) 3307 { 3308 ASSERT(atomic_read(&ticket->t_ref) > 0); 3309 if (atomic_dec_and_test(&ticket->t_ref)) { 3310 sv_destroy(&ticket->t_wait); 3311 kmem_zone_free(xfs_log_ticket_zone, ticket); 3312 } 3313 } 3314 3315 xlog_ticket_t * 3316 xfs_log_ticket_get( 3317 xlog_ticket_t *ticket) 3318 { 3319 ASSERT(atomic_read(&ticket->t_ref) > 0); 3320 atomic_inc(&ticket->t_ref); 3321 return ticket; 3322 } 3323 3324 /* 3325 * Allocate and initialise a new log ticket. 3326 */ 3327 STATIC xlog_ticket_t * 3328 xlog_ticket_alloc( 3329 struct log *log, 3330 int unit_bytes, 3331 int cnt, 3332 char client, 3333 uint xflags) 3334 { 3335 struct xlog_ticket *tic; 3336 uint num_headers; 3337 int iclog_space; 3338 3339 tic = kmem_zone_zalloc(xfs_log_ticket_zone, KM_SLEEP|KM_MAYFAIL); 3340 if (!tic) 3341 return NULL; 3342 3343 /* 3344 * Permanent reservations have up to 'cnt'-1 active log operations 3345 * in the log. A unit in this case is the amount of space for one 3346 * of these log operations. Normal reservations have a cnt of 1 3347 * and their unit amount is the total amount of space required. 3348 * 3349 * The following lines of code account for non-transaction data 3350 * which occupy space in the on-disk log. 3351 * 3352 * Normal form of a transaction is: 3353 * <oph><trans-hdr><start-oph><reg1-oph><reg1><reg2-oph>...<commit-oph> 3354 * and then there are LR hdrs, split-recs and roundoff at end of syncs. 3355 * 3356 * We need to account for all the leadup data and trailer data 3357 * around the transaction data. 3358 * And then we need to account for the worst case in terms of using 3359 * more space. 3360 * The worst case will happen if: 3361 * - the placement of the transaction happens to be such that the 3362 * roundoff is at its maximum 3363 * - the transaction data is synced before the commit record is synced 3364 * i.e. <transaction-data><roundoff> | <commit-rec><roundoff> 3365 * Therefore the commit record is in its own Log Record. 3366 * This can happen as the commit record is called with its 3367 * own region to xlog_write(). 3368 * This then means that in the worst case, roundoff can happen for 3369 * the commit-rec as well. 3370 * The commit-rec is smaller than padding in this scenario and so it is 3371 * not added separately. 3372 */ 3373 3374 /* for trans header */ 3375 unit_bytes += sizeof(xlog_op_header_t); 3376 unit_bytes += sizeof(xfs_trans_header_t); 3377 3378 /* for start-rec */ 3379 unit_bytes += sizeof(xlog_op_header_t); 3380 3381 /* 3382 * for LR headers - the space for data in an iclog is the size minus 3383 * the space used for the headers. If we use the iclog size, then we 3384 * undercalculate the number of headers required. 3385 * 3386 * Furthermore - the addition of op headers for split-recs might 3387 * increase the space required enough to require more log and op 3388 * headers, so take that into account too. 3389 * 3390 * IMPORTANT: This reservation makes the assumption that if this 3391 * transaction is the first in an iclog and hence has the LR headers 3392 * accounted to it, then the remaining space in the iclog is 3393 * exclusively for this transaction. i.e. if the transaction is larger 3394 * than the iclog, it will be the only thing in that iclog. 3395 * Fundamentally, this means we must pass the entire log vector to 3396 * xlog_write to guarantee this. 3397 */ 3398 iclog_space = log->l_iclog_size - log->l_iclog_hsize; 3399 num_headers = howmany(unit_bytes, iclog_space); 3400 3401 /* for split-recs - ophdrs added when data split over LRs */ 3402 unit_bytes += sizeof(xlog_op_header_t) * num_headers; 3403 3404 /* add extra header reservations if we overrun */ 3405 while (!num_headers || 3406 howmany(unit_bytes, iclog_space) > num_headers) { 3407 unit_bytes += sizeof(xlog_op_header_t); 3408 num_headers++; 3409 } 3410 unit_bytes += log->l_iclog_hsize * num_headers; 3411 3412 /* for commit-rec LR header - note: padding will subsume the ophdr */ 3413 unit_bytes += log->l_iclog_hsize; 3414 3415 /* for roundoff padding for transaction data and one for commit record */ 3416 if (xfs_sb_version_haslogv2(&log->l_mp->m_sb) && 3417 log->l_mp->m_sb.sb_logsunit > 1) { 3418 /* log su roundoff */ 3419 unit_bytes += 2*log->l_mp->m_sb.sb_logsunit; 3420 } else { 3421 /* BB roundoff */ 3422 unit_bytes += 2*BBSIZE; 3423 } 3424 3425 atomic_set(&tic->t_ref, 1); 3426 tic->t_unit_res = unit_bytes; 3427 tic->t_curr_res = unit_bytes; 3428 tic->t_cnt = cnt; 3429 tic->t_ocnt = cnt; 3430 tic->t_tid = (xlog_tid_t)((__psint_t)tic & 0xffffffff); 3431 tic->t_clientid = client; 3432 tic->t_flags = XLOG_TIC_INITED; 3433 tic->t_trans_type = 0; 3434 if (xflags & XFS_LOG_PERM_RESERV) 3435 tic->t_flags |= XLOG_TIC_PERM_RESERV; 3436 sv_init(&tic->t_wait, SV_DEFAULT, "logtick"); 3437 3438 xlog_tic_reset_res(tic); 3439 3440 return tic; 3441 } 3442 3443 3444 /****************************************************************************** 3445 * 3446 * Log debug routines 3447 * 3448 ****************************************************************************** 3449 */ 3450 #if defined(DEBUG) 3451 /* 3452 * Make sure that the destination ptr is within the valid data region of 3453 * one of the iclogs. This uses backup pointers stored in a different 3454 * part of the log in case we trash the log structure. 3455 */ 3456 void 3457 xlog_verify_dest_ptr(xlog_t *log, 3458 __psint_t ptr) 3459 { 3460 int i; 3461 int good_ptr = 0; 3462 3463 for (i=0; i < log->l_iclog_bufs; i++) { 3464 if (ptr >= (__psint_t)log->l_iclog_bak[i] && 3465 ptr <= (__psint_t)log->l_iclog_bak[i]+log->l_iclog_size) 3466 good_ptr++; 3467 } 3468 if (! good_ptr) 3469 xlog_panic("xlog_verify_dest_ptr: invalid ptr"); 3470 } /* xlog_verify_dest_ptr */ 3471 3472 STATIC void 3473 xlog_verify_grant_head(xlog_t *log, int equals) 3474 { 3475 if (log->l_grant_reserve_cycle == log->l_grant_write_cycle) { 3476 if (equals) 3477 ASSERT(log->l_grant_reserve_bytes >= log->l_grant_write_bytes); 3478 else 3479 ASSERT(log->l_grant_reserve_bytes > log->l_grant_write_bytes); 3480 } else { 3481 ASSERT(log->l_grant_reserve_cycle-1 == log->l_grant_write_cycle); 3482 ASSERT(log->l_grant_write_bytes >= log->l_grant_reserve_bytes); 3483 } 3484 } /* xlog_verify_grant_head */ 3485 3486 /* check if it will fit */ 3487 STATIC void 3488 xlog_verify_tail_lsn(xlog_t *log, 3489 xlog_in_core_t *iclog, 3490 xfs_lsn_t tail_lsn) 3491 { 3492 int blocks; 3493 3494 if (CYCLE_LSN(tail_lsn) == log->l_prev_cycle) { 3495 blocks = 3496 log->l_logBBsize - (log->l_prev_block - BLOCK_LSN(tail_lsn)); 3497 if (blocks < BTOBB(iclog->ic_offset)+BTOBB(log->l_iclog_hsize)) 3498 xlog_panic("xlog_verify_tail_lsn: ran out of log space"); 3499 } else { 3500 ASSERT(CYCLE_LSN(tail_lsn)+1 == log->l_prev_cycle); 3501 3502 if (BLOCK_LSN(tail_lsn) == log->l_prev_block) 3503 xlog_panic("xlog_verify_tail_lsn: tail wrapped"); 3504 3505 blocks = BLOCK_LSN(tail_lsn) - log->l_prev_block; 3506 if (blocks < BTOBB(iclog->ic_offset) + 1) 3507 xlog_panic("xlog_verify_tail_lsn: ran out of log space"); 3508 } 3509 } /* xlog_verify_tail_lsn */ 3510 3511 /* 3512 * Perform a number of checks on the iclog before writing to disk. 3513 * 3514 * 1. Make sure the iclogs are still circular 3515 * 2. Make sure we have a good magic number 3516 * 3. Make sure we don't have magic numbers in the data 3517 * 4. Check fields of each log operation header for: 3518 * A. Valid client identifier 3519 * B. tid ptr value falls in valid ptr space (user space code) 3520 * C. Length in log record header is correct according to the 3521 * individual operation headers within record. 3522 * 5. When a bwrite will occur within 5 blocks of the front of the physical 3523 * log, check the preceding blocks of the physical log to make sure all 3524 * the cycle numbers agree with the current cycle number. 3525 */ 3526 STATIC void 3527 xlog_verify_iclog(xlog_t *log, 3528 xlog_in_core_t *iclog, 3529 int count, 3530 boolean_t syncing) 3531 { 3532 xlog_op_header_t *ophead; 3533 xlog_in_core_t *icptr; 3534 xlog_in_core_2_t *xhdr; 3535 xfs_caddr_t ptr; 3536 xfs_caddr_t base_ptr; 3537 __psint_t field_offset; 3538 __uint8_t clientid; 3539 int len, i, j, k, op_len; 3540 int idx; 3541 3542 /* check validity of iclog pointers */ 3543 spin_lock(&log->l_icloglock); 3544 icptr = log->l_iclog; 3545 for (i=0; i < log->l_iclog_bufs; i++) { 3546 if (icptr == NULL) 3547 xlog_panic("xlog_verify_iclog: invalid ptr"); 3548 icptr = icptr->ic_next; 3549 } 3550 if (icptr != log->l_iclog) 3551 xlog_panic("xlog_verify_iclog: corrupt iclog ring"); 3552 spin_unlock(&log->l_icloglock); 3553 3554 /* check log magic numbers */ 3555 if (be32_to_cpu(iclog->ic_header.h_magicno) != XLOG_HEADER_MAGIC_NUM) 3556 xlog_panic("xlog_verify_iclog: invalid magic num"); 3557 3558 ptr = (xfs_caddr_t) &iclog->ic_header; 3559 for (ptr += BBSIZE; ptr < ((xfs_caddr_t)&iclog->ic_header) + count; 3560 ptr += BBSIZE) { 3561 if (be32_to_cpu(*(__be32 *)ptr) == XLOG_HEADER_MAGIC_NUM) 3562 xlog_panic("xlog_verify_iclog: unexpected magic num"); 3563 } 3564 3565 /* check fields */ 3566 len = be32_to_cpu(iclog->ic_header.h_num_logops); 3567 ptr = iclog->ic_datap; 3568 base_ptr = ptr; 3569 ophead = (xlog_op_header_t *)ptr; 3570 xhdr = iclog->ic_data; 3571 for (i = 0; i < len; i++) { 3572 ophead = (xlog_op_header_t *)ptr; 3573 3574 /* clientid is only 1 byte */ 3575 field_offset = (__psint_t) 3576 ((xfs_caddr_t)&(ophead->oh_clientid) - base_ptr); 3577 if (syncing == B_FALSE || (field_offset & 0x1ff)) { 3578 clientid = ophead->oh_clientid; 3579 } else { 3580 idx = BTOBBT((xfs_caddr_t)&(ophead->oh_clientid) - iclog->ic_datap); 3581 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) { 3582 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3583 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3584 clientid = xlog_get_client_id( 3585 xhdr[j].hic_xheader.xh_cycle_data[k]); 3586 } else { 3587 clientid = xlog_get_client_id( 3588 iclog->ic_header.h_cycle_data[idx]); 3589 } 3590 } 3591 if (clientid != XFS_TRANSACTION && clientid != XFS_LOG) 3592 cmn_err(CE_WARN, "xlog_verify_iclog: " 3593 "invalid clientid %d op 0x%p offset 0x%lx", 3594 clientid, ophead, (unsigned long)field_offset); 3595 3596 /* check length */ 3597 field_offset = (__psint_t) 3598 ((xfs_caddr_t)&(ophead->oh_len) - base_ptr); 3599 if (syncing == B_FALSE || (field_offset & 0x1ff)) { 3600 op_len = be32_to_cpu(ophead->oh_len); 3601 } else { 3602 idx = BTOBBT((__psint_t)&ophead->oh_len - 3603 (__psint_t)iclog->ic_datap); 3604 if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) { 3605 j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3606 k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE); 3607 op_len = be32_to_cpu(xhdr[j].hic_xheader.xh_cycle_data[k]); 3608 } else { 3609 op_len = be32_to_cpu(iclog->ic_header.h_cycle_data[idx]); 3610 } 3611 } 3612 ptr += sizeof(xlog_op_header_t) + op_len; 3613 } 3614 } /* xlog_verify_iclog */ 3615 #endif 3616 3617 /* 3618 * Mark all iclogs IOERROR. l_icloglock is held by the caller. 3619 */ 3620 STATIC int 3621 xlog_state_ioerror( 3622 xlog_t *log) 3623 { 3624 xlog_in_core_t *iclog, *ic; 3625 3626 iclog = log->l_iclog; 3627 if (! (iclog->ic_state & XLOG_STATE_IOERROR)) { 3628 /* 3629 * Mark all the incore logs IOERROR. 3630 * From now on, no log flushes will result. 3631 */ 3632 ic = iclog; 3633 do { 3634 ic->ic_state = XLOG_STATE_IOERROR; 3635 ic = ic->ic_next; 3636 } while (ic != iclog); 3637 return 0; 3638 } 3639 /* 3640 * Return non-zero, if state transition has already happened. 3641 */ 3642 return 1; 3643 } 3644 3645 /* 3646 * This is called from xfs_force_shutdown, when we're forcibly 3647 * shutting down the filesystem, typically because of an IO error. 3648 * Our main objectives here are to make sure that: 3649 * a. the filesystem gets marked 'SHUTDOWN' for all interested 3650 * parties to find out, 'atomically'. 3651 * b. those who're sleeping on log reservations, pinned objects and 3652 * other resources get woken up, and be told the bad news. 3653 * c. nothing new gets queued up after (a) and (b) are done. 3654 * d. if !logerror, flush the iclogs to disk, then seal them off 3655 * for business. 3656 */ 3657 int 3658 xfs_log_force_umount( 3659 struct xfs_mount *mp, 3660 int logerror) 3661 { 3662 xlog_ticket_t *tic; 3663 xlog_t *log; 3664 int retval; 3665 3666 log = mp->m_log; 3667 3668 /* 3669 * If this happens during log recovery, don't worry about 3670 * locking; the log isn't open for business yet. 3671 */ 3672 if (!log || 3673 log->l_flags & XLOG_ACTIVE_RECOVERY) { 3674 mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN; 3675 if (mp->m_sb_bp) 3676 XFS_BUF_DONE(mp->m_sb_bp); 3677 return 0; 3678 } 3679 3680 /* 3681 * Somebody could've already done the hard work for us. 3682 * No need to get locks for this. 3683 */ 3684 if (logerror && log->l_iclog->ic_state & XLOG_STATE_IOERROR) { 3685 ASSERT(XLOG_FORCED_SHUTDOWN(log)); 3686 return 1; 3687 } 3688 retval = 0; 3689 /* 3690 * We must hold both the GRANT lock and the LOG lock, 3691 * before we mark the filesystem SHUTDOWN and wake 3692 * everybody up to tell the bad news. 3693 */ 3694 spin_lock(&log->l_icloglock); 3695 spin_lock(&log->l_grant_lock); 3696 mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN; 3697 if (mp->m_sb_bp) 3698 XFS_BUF_DONE(mp->m_sb_bp); 3699 3700 /* 3701 * This flag is sort of redundant because of the mount flag, but 3702 * it's good to maintain the separation between the log and the rest 3703 * of XFS. 3704 */ 3705 log->l_flags |= XLOG_IO_ERROR; 3706 3707 /* 3708 * If we hit a log error, we want to mark all the iclogs IOERROR 3709 * while we're still holding the loglock. 3710 */ 3711 if (logerror) 3712 retval = xlog_state_ioerror(log); 3713 spin_unlock(&log->l_icloglock); 3714 3715 /* 3716 * We don't want anybody waiting for log reservations 3717 * after this. That means we have to wake up everybody 3718 * queued up on reserve_headq as well as write_headq. 3719 * In addition, we make sure in xlog_{re}grant_log_space 3720 * that we don't enqueue anything once the SHUTDOWN flag 3721 * is set, and this action is protected by the GRANTLOCK. 3722 */ 3723 if ((tic = log->l_reserve_headq)) { 3724 do { 3725 sv_signal(&tic->t_wait); 3726 tic = tic->t_next; 3727 } while (tic != log->l_reserve_headq); 3728 } 3729 3730 if ((tic = log->l_write_headq)) { 3731 do { 3732 sv_signal(&tic->t_wait); 3733 tic = tic->t_next; 3734 } while (tic != log->l_write_headq); 3735 } 3736 spin_unlock(&log->l_grant_lock); 3737 3738 if (!(log->l_iclog->ic_state & XLOG_STATE_IOERROR)) { 3739 ASSERT(!logerror); 3740 /* 3741 * Force the incore logs to disk before shutting the 3742 * log down completely. 3743 */ 3744 _xfs_log_force(mp, XFS_LOG_SYNC, NULL); 3745 3746 spin_lock(&log->l_icloglock); 3747 retval = xlog_state_ioerror(log); 3748 spin_unlock(&log->l_icloglock); 3749 } 3750 /* 3751 * Wake up everybody waiting on xfs_log_force. 3752 * Callback all log item committed functions as if the 3753 * log writes were completed. 3754 */ 3755 xlog_state_do_callback(log, XFS_LI_ABORTED, NULL); 3756 3757 #ifdef XFSERRORDEBUG 3758 { 3759 xlog_in_core_t *iclog; 3760 3761 spin_lock(&log->l_icloglock); 3762 iclog = log->l_iclog; 3763 do { 3764 ASSERT(iclog->ic_callback == 0); 3765 iclog = iclog->ic_next; 3766 } while (iclog != log->l_iclog); 3767 spin_unlock(&log->l_icloglock); 3768 } 3769 #endif 3770 /* return non-zero if log IOERROR transition had already happened */ 3771 return retval; 3772 } 3773 3774 STATIC int 3775 xlog_iclogs_empty(xlog_t *log) 3776 { 3777 xlog_in_core_t *iclog; 3778 3779 iclog = log->l_iclog; 3780 do { 3781 /* endianness does not matter here, zero is zero in 3782 * any language. 3783 */ 3784 if (iclog->ic_header.h_num_logops) 3785 return 0; 3786 iclog = iclog->ic_next; 3787 } while (iclog != log->l_iclog); 3788 return 1; 3789 } 3790