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