1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2000-2005 Silicon Graphics, Inc. 4 * All Rights Reserved. 5 */ 6 #include "xfs.h" 7 #include "xfs_fs.h" 8 #include "xfs_shared.h" 9 #include "xfs_format.h" 10 #include "xfs_log_format.h" 11 #include "xfs_trans_resv.h" 12 #include "xfs_sb.h" 13 #include "xfs_mount.h" 14 #include "xfs_trans.h" 15 #include "xfs_error.h" 16 #include "xfs_alloc.h" 17 #include "xfs_fsops.h" 18 #include "xfs_trans_space.h" 19 #include "xfs_log.h" 20 #include "xfs_log_priv.h" 21 #include "xfs_ag.h" 22 #include "xfs_ag_resv.h" 23 #include "xfs_trace.h" 24 25 /* 26 * Write new AG headers to disk. Non-transactional, but need to be 27 * written and completed prior to the growfs transaction being logged. 28 * To do this, we use a delayed write buffer list and wait for 29 * submission and IO completion of the list as a whole. This allows the 30 * IO subsystem to merge all the AG headers in a single AG into a single 31 * IO and hide most of the latency of the IO from us. 32 * 33 * This also means that if we get an error whilst building the buffer 34 * list to write, we can cancel the entire list without having written 35 * anything. 36 */ 37 static int 38 xfs_resizefs_init_new_ags( 39 struct xfs_trans *tp, 40 struct aghdr_init_data *id, 41 xfs_agnumber_t oagcount, 42 xfs_agnumber_t nagcount, 43 xfs_rfsblock_t delta, 44 bool *lastag_extended) 45 { 46 struct xfs_mount *mp = tp->t_mountp; 47 xfs_rfsblock_t nb = mp->m_sb.sb_dblocks + delta; 48 int error; 49 50 *lastag_extended = false; 51 52 INIT_LIST_HEAD(&id->buffer_list); 53 for (id->agno = nagcount - 1; 54 id->agno >= oagcount; 55 id->agno--, delta -= id->agsize) { 56 57 if (id->agno == nagcount - 1) 58 id->agsize = nb - (id->agno * 59 (xfs_rfsblock_t)mp->m_sb.sb_agblocks); 60 else 61 id->agsize = mp->m_sb.sb_agblocks; 62 63 error = xfs_ag_init_headers(mp, id); 64 if (error) { 65 xfs_buf_delwri_cancel(&id->buffer_list); 66 return error; 67 } 68 } 69 70 error = xfs_buf_delwri_submit(&id->buffer_list); 71 if (error) 72 return error; 73 74 if (delta) { 75 *lastag_extended = true; 76 error = xfs_ag_extend_space(mp, tp, id, delta); 77 } 78 return error; 79 } 80 81 /* 82 * growfs operations 83 */ 84 static int 85 xfs_growfs_data_private( 86 struct xfs_mount *mp, /* mount point for filesystem */ 87 struct xfs_growfs_data *in) /* growfs data input struct */ 88 { 89 struct xfs_buf *bp; 90 int error; 91 xfs_agnumber_t nagcount; 92 xfs_agnumber_t nagimax = 0; 93 xfs_rfsblock_t nb, nb_div, nb_mod; 94 int64_t delta; 95 bool lastag_extended; 96 xfs_agnumber_t oagcount; 97 struct xfs_trans *tp; 98 struct aghdr_init_data id = {}; 99 100 nb = in->newblocks; 101 error = xfs_sb_validate_fsb_count(&mp->m_sb, nb); 102 if (error) 103 return error; 104 105 if (nb > mp->m_sb.sb_dblocks) { 106 error = xfs_buf_read_uncached(mp->m_ddev_targp, 107 XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1), 108 XFS_FSS_TO_BB(mp, 1), 0, &bp, NULL); 109 if (error) 110 return error; 111 xfs_buf_relse(bp); 112 } 113 114 nb_div = nb; 115 nb_mod = do_div(nb_div, mp->m_sb.sb_agblocks); 116 nagcount = nb_div + (nb_mod != 0); 117 if (nb_mod && nb_mod < XFS_MIN_AG_BLOCKS) { 118 nagcount--; 119 nb = (xfs_rfsblock_t)nagcount * mp->m_sb.sb_agblocks; 120 } 121 delta = nb - mp->m_sb.sb_dblocks; 122 /* 123 * Reject filesystems with a single AG because they are not 124 * supported, and reject a shrink operation that would cause a 125 * filesystem to become unsupported. 126 */ 127 if (delta < 0 && nagcount < 2) 128 return -EINVAL; 129 130 oagcount = mp->m_sb.sb_agcount; 131 132 /* allocate the new per-ag structures */ 133 if (nagcount > oagcount) { 134 error = xfs_initialize_perag(mp, nagcount, &nagimax); 135 if (error) 136 return error; 137 } else if (nagcount < oagcount) { 138 /* TODO: shrinking the entire AGs hasn't yet completed */ 139 return -EINVAL; 140 } 141 142 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata, 143 (delta > 0 ? XFS_GROWFS_SPACE_RES(mp) : -delta), 0, 144 XFS_TRANS_RESERVE, &tp); 145 if (error) 146 return error; 147 148 if (delta > 0) { 149 error = xfs_resizefs_init_new_ags(tp, &id, oagcount, nagcount, 150 delta, &lastag_extended); 151 } else { 152 xfs_warn_mount(mp, XFS_OPSTATE_WARNED_SHRINK, 153 "EXPERIMENTAL online shrink feature in use. Use at your own risk!"); 154 155 error = xfs_ag_shrink_space(mp, &tp, nagcount - 1, -delta); 156 } 157 if (error) 158 goto out_trans_cancel; 159 160 /* 161 * Update changed superblock fields transactionally. These are not 162 * seen by the rest of the world until the transaction commit applies 163 * them atomically to the superblock. 164 */ 165 if (nagcount > oagcount) 166 xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount); 167 if (delta) 168 xfs_trans_mod_sb(tp, XFS_TRANS_SB_DBLOCKS, delta); 169 if (id.nfree) 170 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, id.nfree); 171 172 /* 173 * Sync sb counters now to reflect the updated values. This is 174 * particularly important for shrink because the write verifier 175 * will fail if sb_fdblocks is ever larger than sb_dblocks. 176 */ 177 if (xfs_has_lazysbcount(mp)) 178 xfs_log_sb(tp); 179 180 xfs_trans_set_sync(tp); 181 error = xfs_trans_commit(tp); 182 if (error) 183 return error; 184 185 /* New allocation groups fully initialized, so update mount struct */ 186 if (nagimax) 187 mp->m_maxagi = nagimax; 188 xfs_set_low_space_thresholds(mp); 189 mp->m_alloc_set_aside = xfs_alloc_set_aside(mp); 190 191 if (delta > 0) { 192 /* 193 * If we expanded the last AG, free the per-AG reservation 194 * so we can reinitialize it with the new size. 195 */ 196 if (lastag_extended) { 197 struct xfs_perag *pag; 198 199 pag = xfs_perag_get(mp, id.agno); 200 error = xfs_ag_resv_free(pag); 201 xfs_perag_put(pag); 202 if (error) 203 return error; 204 } 205 /* 206 * Reserve AG metadata blocks. ENOSPC here does not mean there 207 * was a growfs failure, just that there still isn't space for 208 * new user data after the grow has been run. 209 */ 210 error = xfs_fs_reserve_ag_blocks(mp); 211 if (error == -ENOSPC) 212 error = 0; 213 } 214 return error; 215 216 out_trans_cancel: 217 xfs_trans_cancel(tp); 218 return error; 219 } 220 221 static int 222 xfs_growfs_log_private( 223 struct xfs_mount *mp, /* mount point for filesystem */ 224 struct xfs_growfs_log *in) /* growfs log input struct */ 225 { 226 xfs_extlen_t nb; 227 228 nb = in->newblocks; 229 if (nb < XFS_MIN_LOG_BLOCKS || nb < XFS_B_TO_FSB(mp, XFS_MIN_LOG_BYTES)) 230 return -EINVAL; 231 if (nb == mp->m_sb.sb_logblocks && 232 in->isint == (mp->m_sb.sb_logstart != 0)) 233 return -EINVAL; 234 /* 235 * Moving the log is hard, need new interfaces to sync 236 * the log first, hold off all activity while moving it. 237 * Can have shorter or longer log in the same space, 238 * or transform internal to external log or vice versa. 239 */ 240 return -ENOSYS; 241 } 242 243 static int 244 xfs_growfs_imaxpct( 245 struct xfs_mount *mp, 246 __u32 imaxpct) 247 { 248 struct xfs_trans *tp; 249 int dpct; 250 int error; 251 252 if (imaxpct > 100) 253 return -EINVAL; 254 255 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata, 256 XFS_GROWFS_SPACE_RES(mp), 0, XFS_TRANS_RESERVE, &tp); 257 if (error) 258 return error; 259 260 dpct = imaxpct - mp->m_sb.sb_imax_pct; 261 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct); 262 xfs_trans_set_sync(tp); 263 return xfs_trans_commit(tp); 264 } 265 266 /* 267 * protected versions of growfs function acquire and release locks on the mount 268 * point - exported through ioctls: XFS_IOC_FSGROWFSDATA, XFS_IOC_FSGROWFSLOG, 269 * XFS_IOC_FSGROWFSRT 270 */ 271 int 272 xfs_growfs_data( 273 struct xfs_mount *mp, 274 struct xfs_growfs_data *in) 275 { 276 int error = 0; 277 278 if (!capable(CAP_SYS_ADMIN)) 279 return -EPERM; 280 if (!mutex_trylock(&mp->m_growlock)) 281 return -EWOULDBLOCK; 282 283 /* update imaxpct separately to the physical grow of the filesystem */ 284 if (in->imaxpct != mp->m_sb.sb_imax_pct) { 285 error = xfs_growfs_imaxpct(mp, in->imaxpct); 286 if (error) 287 goto out_error; 288 } 289 290 if (in->newblocks != mp->m_sb.sb_dblocks) { 291 error = xfs_growfs_data_private(mp, in); 292 if (error) 293 goto out_error; 294 } 295 296 /* Post growfs calculations needed to reflect new state in operations */ 297 if (mp->m_sb.sb_imax_pct) { 298 uint64_t icount = mp->m_sb.sb_dblocks * mp->m_sb.sb_imax_pct; 299 do_div(icount, 100); 300 M_IGEO(mp)->maxicount = XFS_FSB_TO_INO(mp, icount); 301 } else 302 M_IGEO(mp)->maxicount = 0; 303 304 /* Update secondary superblocks now the physical grow has completed */ 305 error = xfs_update_secondary_sbs(mp); 306 307 out_error: 308 /* 309 * Increment the generation unconditionally, the error could be from 310 * updating the secondary superblocks, in which case the new size 311 * is live already. 312 */ 313 mp->m_generation++; 314 mutex_unlock(&mp->m_growlock); 315 return error; 316 } 317 318 int 319 xfs_growfs_log( 320 xfs_mount_t *mp, 321 struct xfs_growfs_log *in) 322 { 323 int error; 324 325 if (!capable(CAP_SYS_ADMIN)) 326 return -EPERM; 327 if (!mutex_trylock(&mp->m_growlock)) 328 return -EWOULDBLOCK; 329 error = xfs_growfs_log_private(mp, in); 330 mutex_unlock(&mp->m_growlock); 331 return error; 332 } 333 334 /* 335 * exported through ioctl XFS_IOC_FSCOUNTS 336 */ 337 338 void 339 xfs_fs_counts( 340 xfs_mount_t *mp, 341 xfs_fsop_counts_t *cnt) 342 { 343 cnt->allocino = percpu_counter_read_positive(&mp->m_icount); 344 cnt->freeino = percpu_counter_read_positive(&mp->m_ifree); 345 cnt->freedata = percpu_counter_read_positive(&mp->m_fdblocks) - 346 xfs_fdblocks_unavailable(mp); 347 cnt->freertx = percpu_counter_read_positive(&mp->m_frextents); 348 } 349 350 /* 351 * exported through ioctl XFS_IOC_SET_RESBLKS & XFS_IOC_GET_RESBLKS 352 * 353 * xfs_reserve_blocks is called to set m_resblks 354 * in the in-core mount table. The number of unused reserved blocks 355 * is kept in m_resblks_avail. 356 * 357 * Reserve the requested number of blocks if available. Otherwise return 358 * as many as possible to satisfy the request. The actual number 359 * reserved are returned in outval 360 * 361 * A null inval pointer indicates that only the current reserved blocks 362 * available should be returned no settings are changed. 363 */ 364 365 int 366 xfs_reserve_blocks( 367 xfs_mount_t *mp, 368 uint64_t *inval, 369 xfs_fsop_resblks_t *outval) 370 { 371 int64_t lcounter, delta; 372 int64_t fdblks_delta = 0; 373 uint64_t request; 374 int64_t free; 375 int error = 0; 376 377 /* If inval is null, report current values and return */ 378 if (inval == (uint64_t *)NULL) { 379 if (!outval) 380 return -EINVAL; 381 outval->resblks = mp->m_resblks; 382 outval->resblks_avail = mp->m_resblks_avail; 383 return 0; 384 } 385 386 request = *inval; 387 388 /* 389 * With per-cpu counters, this becomes an interesting problem. we need 390 * to work out if we are freeing or allocation blocks first, then we can 391 * do the modification as necessary. 392 * 393 * We do this under the m_sb_lock so that if we are near ENOSPC, we will 394 * hold out any changes while we work out what to do. This means that 395 * the amount of free space can change while we do this, so we need to 396 * retry if we end up trying to reserve more space than is available. 397 */ 398 spin_lock(&mp->m_sb_lock); 399 400 /* 401 * If our previous reservation was larger than the current value, 402 * then move any unused blocks back to the free pool. Modify the resblks 403 * counters directly since we shouldn't have any problems unreserving 404 * space. 405 */ 406 if (mp->m_resblks > request) { 407 lcounter = mp->m_resblks_avail - request; 408 if (lcounter > 0) { /* release unused blocks */ 409 fdblks_delta = lcounter; 410 mp->m_resblks_avail -= lcounter; 411 } 412 mp->m_resblks = request; 413 if (fdblks_delta) { 414 spin_unlock(&mp->m_sb_lock); 415 error = xfs_mod_fdblocks(mp, fdblks_delta, 0); 416 spin_lock(&mp->m_sb_lock); 417 } 418 419 goto out; 420 } 421 422 /* 423 * If the request is larger than the current reservation, reserve the 424 * blocks before we update the reserve counters. Sample m_fdblocks and 425 * perform a partial reservation if the request exceeds free space. 426 * 427 * The code below estimates how many blocks it can request from 428 * fdblocks to stash in the reserve pool. This is a classic TOCTOU 429 * race since fdblocks updates are not always coordinated via 430 * m_sb_lock. Set the reserve size even if there's not enough free 431 * space to fill it because mod_fdblocks will refill an undersized 432 * reserve when it can. 433 */ 434 free = percpu_counter_sum(&mp->m_fdblocks) - 435 xfs_fdblocks_unavailable(mp); 436 delta = request - mp->m_resblks; 437 mp->m_resblks = request; 438 if (delta > 0 && free > 0) { 439 /* 440 * We'll either succeed in getting space from the free block 441 * count or we'll get an ENOSPC. Don't set the reserved flag 442 * here - we don't want to reserve the extra reserve blocks 443 * from the reserve. 444 * 445 * The desired reserve size can change after we drop the lock. 446 * Use mod_fdblocks to put the space into the reserve or into 447 * fdblocks as appropriate. 448 */ 449 fdblks_delta = min(free, delta); 450 spin_unlock(&mp->m_sb_lock); 451 error = xfs_mod_fdblocks(mp, -fdblks_delta, 0); 452 if (!error) 453 xfs_mod_fdblocks(mp, fdblks_delta, 0); 454 spin_lock(&mp->m_sb_lock); 455 } 456 out: 457 if (outval) { 458 outval->resblks = mp->m_resblks; 459 outval->resblks_avail = mp->m_resblks_avail; 460 } 461 462 spin_unlock(&mp->m_sb_lock); 463 return error; 464 } 465 466 int 467 xfs_fs_goingdown( 468 xfs_mount_t *mp, 469 uint32_t inflags) 470 { 471 switch (inflags) { 472 case XFS_FSOP_GOING_FLAGS_DEFAULT: { 473 if (!freeze_bdev(mp->m_super->s_bdev)) { 474 xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT); 475 thaw_bdev(mp->m_super->s_bdev); 476 } 477 break; 478 } 479 case XFS_FSOP_GOING_FLAGS_LOGFLUSH: 480 xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT); 481 break; 482 case XFS_FSOP_GOING_FLAGS_NOLOGFLUSH: 483 xfs_force_shutdown(mp, 484 SHUTDOWN_FORCE_UMOUNT | SHUTDOWN_LOG_IO_ERROR); 485 break; 486 default: 487 return -EINVAL; 488 } 489 490 return 0; 491 } 492 493 /* 494 * Force a shutdown of the filesystem instantly while keeping the filesystem 495 * consistent. We don't do an unmount here; just shutdown the shop, make sure 496 * that absolutely nothing persistent happens to this filesystem after this 497 * point. 498 * 499 * The shutdown state change is atomic, resulting in the first and only the 500 * first shutdown call processing the shutdown. This means we only shutdown the 501 * log once as it requires, and we don't spam the logs when multiple concurrent 502 * shutdowns race to set the shutdown flags. 503 */ 504 void 505 xfs_do_force_shutdown( 506 struct xfs_mount *mp, 507 uint32_t flags, 508 char *fname, 509 int lnnum) 510 { 511 int tag; 512 const char *why; 513 514 515 if (test_and_set_bit(XFS_OPSTATE_SHUTDOWN, &mp->m_opstate)) { 516 xlog_shutdown_wait(mp->m_log); 517 return; 518 } 519 if (mp->m_sb_bp) 520 mp->m_sb_bp->b_flags |= XBF_DONE; 521 522 if (flags & SHUTDOWN_FORCE_UMOUNT) 523 xfs_alert(mp, "User initiated shutdown received."); 524 525 if (xlog_force_shutdown(mp->m_log, flags)) { 526 tag = XFS_PTAG_SHUTDOWN_LOGERROR; 527 why = "Log I/O Error"; 528 } else if (flags & SHUTDOWN_CORRUPT_INCORE) { 529 tag = XFS_PTAG_SHUTDOWN_CORRUPT; 530 why = "Corruption of in-memory data"; 531 } else { 532 tag = XFS_PTAG_SHUTDOWN_IOERROR; 533 why = "Metadata I/O Error"; 534 } 535 536 trace_xfs_force_shutdown(mp, tag, flags, fname, lnnum); 537 538 xfs_alert_tag(mp, tag, 539 "%s (0x%x) detected at %pS (%s:%d). Shutting down filesystem.", 540 why, flags, __return_address, fname, lnnum); 541 xfs_alert(mp, 542 "Please unmount the filesystem and rectify the problem(s)"); 543 if (xfs_error_level >= XFS_ERRLEVEL_HIGH) 544 xfs_stack_trace(); 545 } 546 547 /* 548 * Reserve free space for per-AG metadata. 549 */ 550 int 551 xfs_fs_reserve_ag_blocks( 552 struct xfs_mount *mp) 553 { 554 xfs_agnumber_t agno; 555 struct xfs_perag *pag; 556 int error = 0; 557 int err2; 558 559 mp->m_finobt_nores = false; 560 for_each_perag(mp, agno, pag) { 561 err2 = xfs_ag_resv_init(pag, NULL); 562 if (err2 && !error) 563 error = err2; 564 } 565 566 if (error && error != -ENOSPC) { 567 xfs_warn(mp, 568 "Error %d reserving per-AG metadata reserve pool.", error); 569 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE); 570 } 571 572 return error; 573 } 574 575 /* 576 * Free space reserved for per-AG metadata. 577 */ 578 int 579 xfs_fs_unreserve_ag_blocks( 580 struct xfs_mount *mp) 581 { 582 xfs_agnumber_t agno; 583 struct xfs_perag *pag; 584 int error = 0; 585 int err2; 586 587 for_each_perag(mp, agno, pag) { 588 err2 = xfs_ag_resv_free(pag); 589 if (err2 && !error) 590 error = err2; 591 } 592 593 if (error) 594 xfs_warn(mp, 595 "Error %d freeing per-AG metadata reserve pool.", error); 596 597 return error; 598 } 599