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_bit.h" 13 #include "xfs_sb.h" 14 #include "xfs_mount.h" 15 #include "xfs_defer.h" 16 #include "xfs_inode.h" 17 #include "xfs_ialloc.h" 18 #include "xfs_alloc.h" 19 #include "xfs_error.h" 20 #include "xfs_trace.h" 21 #include "xfs_cksum.h" 22 #include "xfs_trans.h" 23 #include "xfs_buf_item.h" 24 #include "xfs_bmap_btree.h" 25 #include "xfs_alloc_btree.h" 26 #include "xfs_ialloc_btree.h" 27 #include "xfs_log.h" 28 #include "xfs_rmap_btree.h" 29 #include "xfs_bmap.h" 30 #include "xfs_refcount_btree.h" 31 #include "xfs_da_format.h" 32 #include "xfs_da_btree.h" 33 34 /* 35 * Physical superblock buffer manipulations. Shared with libxfs in userspace. 36 */ 37 38 /* 39 * Reference counting access wrappers to the perag structures. 40 * Because we never free per-ag structures, the only thing we 41 * have to protect against changes is the tree structure itself. 42 */ 43 struct xfs_perag * 44 xfs_perag_get( 45 struct xfs_mount *mp, 46 xfs_agnumber_t agno) 47 { 48 struct xfs_perag *pag; 49 int ref = 0; 50 51 rcu_read_lock(); 52 pag = radix_tree_lookup(&mp->m_perag_tree, agno); 53 if (pag) { 54 ASSERT(atomic_read(&pag->pag_ref) >= 0); 55 ref = atomic_inc_return(&pag->pag_ref); 56 } 57 rcu_read_unlock(); 58 trace_xfs_perag_get(mp, agno, ref, _RET_IP_); 59 return pag; 60 } 61 62 /* 63 * search from @first to find the next perag with the given tag set. 64 */ 65 struct xfs_perag * 66 xfs_perag_get_tag( 67 struct xfs_mount *mp, 68 xfs_agnumber_t first, 69 int tag) 70 { 71 struct xfs_perag *pag; 72 int found; 73 int ref; 74 75 rcu_read_lock(); 76 found = radix_tree_gang_lookup_tag(&mp->m_perag_tree, 77 (void **)&pag, first, 1, tag); 78 if (found <= 0) { 79 rcu_read_unlock(); 80 return NULL; 81 } 82 ref = atomic_inc_return(&pag->pag_ref); 83 rcu_read_unlock(); 84 trace_xfs_perag_get_tag(mp, pag->pag_agno, ref, _RET_IP_); 85 return pag; 86 } 87 88 void 89 xfs_perag_put( 90 struct xfs_perag *pag) 91 { 92 int ref; 93 94 ASSERT(atomic_read(&pag->pag_ref) > 0); 95 ref = atomic_dec_return(&pag->pag_ref); 96 trace_xfs_perag_put(pag->pag_mount, pag->pag_agno, ref, _RET_IP_); 97 } 98 99 /* 100 * Check the validity of the SB found. 101 */ 102 STATIC int 103 xfs_mount_validate_sb( 104 xfs_mount_t *mp, 105 xfs_sb_t *sbp, 106 bool check_inprogress, 107 bool check_version) 108 { 109 uint32_t agcount = 0; 110 uint32_t rem; 111 112 if (sbp->sb_magicnum != XFS_SB_MAGIC) { 113 xfs_warn(mp, "bad magic number"); 114 return -EWRONGFS; 115 } 116 117 118 if (!xfs_sb_good_version(sbp)) { 119 xfs_warn(mp, "bad version"); 120 return -EWRONGFS; 121 } 122 123 /* 124 * Version 5 superblock feature mask validation. Reject combinations the 125 * kernel cannot support up front before checking anything else. For 126 * write validation, we don't need to check feature masks. 127 */ 128 if (check_version && XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) { 129 if (xfs_sb_has_compat_feature(sbp, 130 XFS_SB_FEAT_COMPAT_UNKNOWN)) { 131 xfs_warn(mp, 132 "Superblock has unknown compatible features (0x%x) enabled.", 133 (sbp->sb_features_compat & 134 XFS_SB_FEAT_COMPAT_UNKNOWN)); 135 xfs_warn(mp, 136 "Using a more recent kernel is recommended."); 137 } 138 139 if (xfs_sb_has_ro_compat_feature(sbp, 140 XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) { 141 xfs_alert(mp, 142 "Superblock has unknown read-only compatible features (0x%x) enabled.", 143 (sbp->sb_features_ro_compat & 144 XFS_SB_FEAT_RO_COMPAT_UNKNOWN)); 145 if (!(mp->m_flags & XFS_MOUNT_RDONLY)) { 146 xfs_warn(mp, 147 "Attempted to mount read-only compatible filesystem read-write."); 148 xfs_warn(mp, 149 "Filesystem can only be safely mounted read only."); 150 151 return -EINVAL; 152 } 153 } 154 if (xfs_sb_has_incompat_feature(sbp, 155 XFS_SB_FEAT_INCOMPAT_UNKNOWN)) { 156 xfs_warn(mp, 157 "Superblock has unknown incompatible features (0x%x) enabled.", 158 (sbp->sb_features_incompat & 159 XFS_SB_FEAT_INCOMPAT_UNKNOWN)); 160 xfs_warn(mp, 161 "Filesystem can not be safely mounted by this kernel."); 162 return -EINVAL; 163 } 164 } else if (xfs_sb_version_hascrc(sbp)) { 165 /* 166 * We can't read verify the sb LSN because the read verifier is 167 * called before the log is allocated and processed. We know the 168 * log is set up before write verifier (!check_version) calls, 169 * so just check it here. 170 */ 171 if (!xfs_log_check_lsn(mp, sbp->sb_lsn)) 172 return -EFSCORRUPTED; 173 } 174 175 if (xfs_sb_version_has_pquotino(sbp)) { 176 if (sbp->sb_qflags & (XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD)) { 177 xfs_notice(mp, 178 "Version 5 of Super block has XFS_OQUOTA bits."); 179 return -EFSCORRUPTED; 180 } 181 } else if (sbp->sb_qflags & (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD | 182 XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD)) { 183 xfs_notice(mp, 184 "Superblock earlier than Version 5 has XFS_[PQ]UOTA_{ENFD|CHKD} bits."); 185 return -EFSCORRUPTED; 186 } 187 188 /* 189 * Full inode chunks must be aligned to inode chunk size when 190 * sparse inodes are enabled to support the sparse chunk 191 * allocation algorithm and prevent overlapping inode records. 192 */ 193 if (xfs_sb_version_hassparseinodes(sbp)) { 194 uint32_t align; 195 196 align = XFS_INODES_PER_CHUNK * sbp->sb_inodesize 197 >> sbp->sb_blocklog; 198 if (sbp->sb_inoalignmt != align) { 199 xfs_warn(mp, 200 "Inode block alignment (%u) must match chunk size (%u) for sparse inodes.", 201 sbp->sb_inoalignmt, align); 202 return -EINVAL; 203 } 204 } 205 206 if (unlikely( 207 sbp->sb_logstart == 0 && mp->m_logdev_targp == mp->m_ddev_targp)) { 208 xfs_warn(mp, 209 "filesystem is marked as having an external log; " 210 "specify logdev on the mount command line."); 211 return -EINVAL; 212 } 213 214 if (unlikely( 215 sbp->sb_logstart != 0 && mp->m_logdev_targp != mp->m_ddev_targp)) { 216 xfs_warn(mp, 217 "filesystem is marked as having an internal log; " 218 "do not specify logdev on the mount command line."); 219 return -EINVAL; 220 } 221 222 /* Compute agcount for this number of dblocks and agblocks */ 223 if (sbp->sb_agblocks) { 224 agcount = div_u64_rem(sbp->sb_dblocks, sbp->sb_agblocks, &rem); 225 if (rem) 226 agcount++; 227 } 228 229 /* 230 * More sanity checking. Most of these were stolen directly from 231 * xfs_repair. 232 */ 233 if (unlikely( 234 sbp->sb_agcount <= 0 || 235 sbp->sb_sectsize < XFS_MIN_SECTORSIZE || 236 sbp->sb_sectsize > XFS_MAX_SECTORSIZE || 237 sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG || 238 sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG || 239 sbp->sb_sectsize != (1 << sbp->sb_sectlog) || 240 sbp->sb_blocksize < XFS_MIN_BLOCKSIZE || 241 sbp->sb_blocksize > XFS_MAX_BLOCKSIZE || 242 sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG || 243 sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG || 244 sbp->sb_blocksize != (1 << sbp->sb_blocklog) || 245 sbp->sb_dirblklog + sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG || 246 sbp->sb_inodesize < XFS_DINODE_MIN_SIZE || 247 sbp->sb_inodesize > XFS_DINODE_MAX_SIZE || 248 sbp->sb_inodelog < XFS_DINODE_MIN_LOG || 249 sbp->sb_inodelog > XFS_DINODE_MAX_LOG || 250 sbp->sb_inodesize != (1 << sbp->sb_inodelog) || 251 sbp->sb_logsunit > XLOG_MAX_RECORD_BSIZE || 252 sbp->sb_inopblock != howmany(sbp->sb_blocksize,sbp->sb_inodesize) || 253 XFS_FSB_TO_B(mp, sbp->sb_agblocks) < XFS_MIN_AG_BYTES || 254 XFS_FSB_TO_B(mp, sbp->sb_agblocks) > XFS_MAX_AG_BYTES || 255 sbp->sb_agblklog != xfs_highbit32(sbp->sb_agblocks - 1) + 1 || 256 agcount == 0 || agcount != sbp->sb_agcount || 257 (sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog) || 258 (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE) || 259 (sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE) || 260 (sbp->sb_imax_pct > 100 /* zero sb_imax_pct is valid */) || 261 sbp->sb_dblocks == 0 || 262 sbp->sb_dblocks > XFS_MAX_DBLOCKS(sbp) || 263 sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp) || 264 sbp->sb_shared_vn != 0)) { 265 xfs_notice(mp, "SB sanity check failed"); 266 return -EFSCORRUPTED; 267 } 268 269 if (sbp->sb_unit) { 270 if (!xfs_sb_version_hasdalign(sbp) || 271 sbp->sb_unit > sbp->sb_width || 272 (sbp->sb_width % sbp->sb_unit) != 0) { 273 xfs_notice(mp, "SB stripe unit sanity check failed"); 274 return -EFSCORRUPTED; 275 } 276 } else if (xfs_sb_version_hasdalign(sbp)) { 277 xfs_notice(mp, "SB stripe alignment sanity check failed"); 278 return -EFSCORRUPTED; 279 } else if (sbp->sb_width) { 280 xfs_notice(mp, "SB stripe width sanity check failed"); 281 return -EFSCORRUPTED; 282 } 283 284 285 if (xfs_sb_version_hascrc(&mp->m_sb) && 286 sbp->sb_blocksize < XFS_MIN_CRC_BLOCKSIZE) { 287 xfs_notice(mp, "v5 SB sanity check failed"); 288 return -EFSCORRUPTED; 289 } 290 291 /* 292 * Until this is fixed only page-sized or smaller data blocks work. 293 */ 294 if (unlikely(sbp->sb_blocksize > PAGE_SIZE)) { 295 xfs_warn(mp, 296 "File system with blocksize %d bytes. " 297 "Only pagesize (%ld) or less will currently work.", 298 sbp->sb_blocksize, PAGE_SIZE); 299 return -ENOSYS; 300 } 301 302 /* 303 * Currently only very few inode sizes are supported. 304 */ 305 switch (sbp->sb_inodesize) { 306 case 256: 307 case 512: 308 case 1024: 309 case 2048: 310 break; 311 default: 312 xfs_warn(mp, "inode size of %d bytes not supported", 313 sbp->sb_inodesize); 314 return -ENOSYS; 315 } 316 317 if (xfs_sb_validate_fsb_count(sbp, sbp->sb_dblocks) || 318 xfs_sb_validate_fsb_count(sbp, sbp->sb_rblocks)) { 319 xfs_warn(mp, 320 "file system too large to be mounted on this system."); 321 return -EFBIG; 322 } 323 324 if (check_inprogress && sbp->sb_inprogress) { 325 xfs_warn(mp, "Offline file system operation in progress!"); 326 return -EFSCORRUPTED; 327 } 328 return 0; 329 } 330 331 void 332 xfs_sb_quota_from_disk(struct xfs_sb *sbp) 333 { 334 /* 335 * older mkfs doesn't initialize quota inodes to NULLFSINO. This 336 * leads to in-core values having two different values for a quota 337 * inode to be invalid: 0 and NULLFSINO. Change it to a single value 338 * NULLFSINO. 339 * 340 * Note that this change affect only the in-core values. These 341 * values are not written back to disk unless any quota information 342 * is written to the disk. Even in that case, sb_pquotino field is 343 * not written to disk unless the superblock supports pquotino. 344 */ 345 if (sbp->sb_uquotino == 0) 346 sbp->sb_uquotino = NULLFSINO; 347 if (sbp->sb_gquotino == 0) 348 sbp->sb_gquotino = NULLFSINO; 349 if (sbp->sb_pquotino == 0) 350 sbp->sb_pquotino = NULLFSINO; 351 352 /* 353 * We need to do these manipilations only if we are working 354 * with an older version of on-disk superblock. 355 */ 356 if (xfs_sb_version_has_pquotino(sbp)) 357 return; 358 359 if (sbp->sb_qflags & XFS_OQUOTA_ENFD) 360 sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ? 361 XFS_PQUOTA_ENFD : XFS_GQUOTA_ENFD; 362 if (sbp->sb_qflags & XFS_OQUOTA_CHKD) 363 sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ? 364 XFS_PQUOTA_CHKD : XFS_GQUOTA_CHKD; 365 sbp->sb_qflags &= ~(XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD); 366 367 if (sbp->sb_qflags & XFS_PQUOTA_ACCT && 368 sbp->sb_gquotino != NULLFSINO) { 369 /* 370 * In older version of superblock, on-disk superblock only 371 * has sb_gquotino, and in-core superblock has both sb_gquotino 372 * and sb_pquotino. But, only one of them is supported at any 373 * point of time. So, if PQUOTA is set in disk superblock, 374 * copy over sb_gquotino to sb_pquotino. The NULLFSINO test 375 * above is to make sure we don't do this twice and wipe them 376 * both out! 377 */ 378 sbp->sb_pquotino = sbp->sb_gquotino; 379 sbp->sb_gquotino = NULLFSINO; 380 } 381 } 382 383 static void 384 __xfs_sb_from_disk( 385 struct xfs_sb *to, 386 xfs_dsb_t *from, 387 bool convert_xquota) 388 { 389 to->sb_magicnum = be32_to_cpu(from->sb_magicnum); 390 to->sb_blocksize = be32_to_cpu(from->sb_blocksize); 391 to->sb_dblocks = be64_to_cpu(from->sb_dblocks); 392 to->sb_rblocks = be64_to_cpu(from->sb_rblocks); 393 to->sb_rextents = be64_to_cpu(from->sb_rextents); 394 memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid)); 395 to->sb_logstart = be64_to_cpu(from->sb_logstart); 396 to->sb_rootino = be64_to_cpu(from->sb_rootino); 397 to->sb_rbmino = be64_to_cpu(from->sb_rbmino); 398 to->sb_rsumino = be64_to_cpu(from->sb_rsumino); 399 to->sb_rextsize = be32_to_cpu(from->sb_rextsize); 400 to->sb_agblocks = be32_to_cpu(from->sb_agblocks); 401 to->sb_agcount = be32_to_cpu(from->sb_agcount); 402 to->sb_rbmblocks = be32_to_cpu(from->sb_rbmblocks); 403 to->sb_logblocks = be32_to_cpu(from->sb_logblocks); 404 to->sb_versionnum = be16_to_cpu(from->sb_versionnum); 405 to->sb_sectsize = be16_to_cpu(from->sb_sectsize); 406 to->sb_inodesize = be16_to_cpu(from->sb_inodesize); 407 to->sb_inopblock = be16_to_cpu(from->sb_inopblock); 408 memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname)); 409 to->sb_blocklog = from->sb_blocklog; 410 to->sb_sectlog = from->sb_sectlog; 411 to->sb_inodelog = from->sb_inodelog; 412 to->sb_inopblog = from->sb_inopblog; 413 to->sb_agblklog = from->sb_agblklog; 414 to->sb_rextslog = from->sb_rextslog; 415 to->sb_inprogress = from->sb_inprogress; 416 to->sb_imax_pct = from->sb_imax_pct; 417 to->sb_icount = be64_to_cpu(from->sb_icount); 418 to->sb_ifree = be64_to_cpu(from->sb_ifree); 419 to->sb_fdblocks = be64_to_cpu(from->sb_fdblocks); 420 to->sb_frextents = be64_to_cpu(from->sb_frextents); 421 to->sb_uquotino = be64_to_cpu(from->sb_uquotino); 422 to->sb_gquotino = be64_to_cpu(from->sb_gquotino); 423 to->sb_qflags = be16_to_cpu(from->sb_qflags); 424 to->sb_flags = from->sb_flags; 425 to->sb_shared_vn = from->sb_shared_vn; 426 to->sb_inoalignmt = be32_to_cpu(from->sb_inoalignmt); 427 to->sb_unit = be32_to_cpu(from->sb_unit); 428 to->sb_width = be32_to_cpu(from->sb_width); 429 to->sb_dirblklog = from->sb_dirblklog; 430 to->sb_logsectlog = from->sb_logsectlog; 431 to->sb_logsectsize = be16_to_cpu(from->sb_logsectsize); 432 to->sb_logsunit = be32_to_cpu(from->sb_logsunit); 433 to->sb_features2 = be32_to_cpu(from->sb_features2); 434 to->sb_bad_features2 = be32_to_cpu(from->sb_bad_features2); 435 to->sb_features_compat = be32_to_cpu(from->sb_features_compat); 436 to->sb_features_ro_compat = be32_to_cpu(from->sb_features_ro_compat); 437 to->sb_features_incompat = be32_to_cpu(from->sb_features_incompat); 438 to->sb_features_log_incompat = 439 be32_to_cpu(from->sb_features_log_incompat); 440 /* crc is only used on disk, not in memory; just init to 0 here. */ 441 to->sb_crc = 0; 442 to->sb_spino_align = be32_to_cpu(from->sb_spino_align); 443 to->sb_pquotino = be64_to_cpu(from->sb_pquotino); 444 to->sb_lsn = be64_to_cpu(from->sb_lsn); 445 /* 446 * sb_meta_uuid is only on disk if it differs from sb_uuid and the 447 * feature flag is set; if not set we keep it only in memory. 448 */ 449 if (xfs_sb_version_hasmetauuid(to)) 450 uuid_copy(&to->sb_meta_uuid, &from->sb_meta_uuid); 451 else 452 uuid_copy(&to->sb_meta_uuid, &from->sb_uuid); 453 /* Convert on-disk flags to in-memory flags? */ 454 if (convert_xquota) 455 xfs_sb_quota_from_disk(to); 456 } 457 458 void 459 xfs_sb_from_disk( 460 struct xfs_sb *to, 461 xfs_dsb_t *from) 462 { 463 __xfs_sb_from_disk(to, from, true); 464 } 465 466 static void 467 xfs_sb_quota_to_disk( 468 struct xfs_dsb *to, 469 struct xfs_sb *from) 470 { 471 uint16_t qflags = from->sb_qflags; 472 473 to->sb_uquotino = cpu_to_be64(from->sb_uquotino); 474 if (xfs_sb_version_has_pquotino(from)) { 475 to->sb_qflags = cpu_to_be16(from->sb_qflags); 476 to->sb_gquotino = cpu_to_be64(from->sb_gquotino); 477 to->sb_pquotino = cpu_to_be64(from->sb_pquotino); 478 return; 479 } 480 481 /* 482 * The in-core version of sb_qflags do not have XFS_OQUOTA_* 483 * flags, whereas the on-disk version does. So, convert incore 484 * XFS_{PG}QUOTA_* flags to on-disk XFS_OQUOTA_* flags. 485 */ 486 qflags &= ~(XFS_PQUOTA_ENFD | XFS_PQUOTA_CHKD | 487 XFS_GQUOTA_ENFD | XFS_GQUOTA_CHKD); 488 489 if (from->sb_qflags & 490 (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD)) 491 qflags |= XFS_OQUOTA_ENFD; 492 if (from->sb_qflags & 493 (XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD)) 494 qflags |= XFS_OQUOTA_CHKD; 495 to->sb_qflags = cpu_to_be16(qflags); 496 497 /* 498 * GQUOTINO and PQUOTINO cannot be used together in versions 499 * of superblock that do not have pquotino. from->sb_flags 500 * tells us which quota is active and should be copied to 501 * disk. If neither are active, we should NULL the inode. 502 * 503 * In all cases, the separate pquotino must remain 0 because it 504 * it beyond the "end" of the valid non-pquotino superblock. 505 */ 506 if (from->sb_qflags & XFS_GQUOTA_ACCT) 507 to->sb_gquotino = cpu_to_be64(from->sb_gquotino); 508 else if (from->sb_qflags & XFS_PQUOTA_ACCT) 509 to->sb_gquotino = cpu_to_be64(from->sb_pquotino); 510 else { 511 /* 512 * We can't rely on just the fields being logged to tell us 513 * that it is safe to write NULLFSINO - we should only do that 514 * if quotas are not actually enabled. Hence only write 515 * NULLFSINO if both in-core quota inodes are NULL. 516 */ 517 if (from->sb_gquotino == NULLFSINO && 518 from->sb_pquotino == NULLFSINO) 519 to->sb_gquotino = cpu_to_be64(NULLFSINO); 520 } 521 522 to->sb_pquotino = 0; 523 } 524 525 void 526 xfs_sb_to_disk( 527 struct xfs_dsb *to, 528 struct xfs_sb *from) 529 { 530 xfs_sb_quota_to_disk(to, from); 531 532 to->sb_magicnum = cpu_to_be32(from->sb_magicnum); 533 to->sb_blocksize = cpu_to_be32(from->sb_blocksize); 534 to->sb_dblocks = cpu_to_be64(from->sb_dblocks); 535 to->sb_rblocks = cpu_to_be64(from->sb_rblocks); 536 to->sb_rextents = cpu_to_be64(from->sb_rextents); 537 memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid)); 538 to->sb_logstart = cpu_to_be64(from->sb_logstart); 539 to->sb_rootino = cpu_to_be64(from->sb_rootino); 540 to->sb_rbmino = cpu_to_be64(from->sb_rbmino); 541 to->sb_rsumino = cpu_to_be64(from->sb_rsumino); 542 to->sb_rextsize = cpu_to_be32(from->sb_rextsize); 543 to->sb_agblocks = cpu_to_be32(from->sb_agblocks); 544 to->sb_agcount = cpu_to_be32(from->sb_agcount); 545 to->sb_rbmblocks = cpu_to_be32(from->sb_rbmblocks); 546 to->sb_logblocks = cpu_to_be32(from->sb_logblocks); 547 to->sb_versionnum = cpu_to_be16(from->sb_versionnum); 548 to->sb_sectsize = cpu_to_be16(from->sb_sectsize); 549 to->sb_inodesize = cpu_to_be16(from->sb_inodesize); 550 to->sb_inopblock = cpu_to_be16(from->sb_inopblock); 551 memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname)); 552 to->sb_blocklog = from->sb_blocklog; 553 to->sb_sectlog = from->sb_sectlog; 554 to->sb_inodelog = from->sb_inodelog; 555 to->sb_inopblog = from->sb_inopblog; 556 to->sb_agblklog = from->sb_agblklog; 557 to->sb_rextslog = from->sb_rextslog; 558 to->sb_inprogress = from->sb_inprogress; 559 to->sb_imax_pct = from->sb_imax_pct; 560 to->sb_icount = cpu_to_be64(from->sb_icount); 561 to->sb_ifree = cpu_to_be64(from->sb_ifree); 562 to->sb_fdblocks = cpu_to_be64(from->sb_fdblocks); 563 to->sb_frextents = cpu_to_be64(from->sb_frextents); 564 565 to->sb_flags = from->sb_flags; 566 to->sb_shared_vn = from->sb_shared_vn; 567 to->sb_inoalignmt = cpu_to_be32(from->sb_inoalignmt); 568 to->sb_unit = cpu_to_be32(from->sb_unit); 569 to->sb_width = cpu_to_be32(from->sb_width); 570 to->sb_dirblklog = from->sb_dirblklog; 571 to->sb_logsectlog = from->sb_logsectlog; 572 to->sb_logsectsize = cpu_to_be16(from->sb_logsectsize); 573 to->sb_logsunit = cpu_to_be32(from->sb_logsunit); 574 575 /* 576 * We need to ensure that bad_features2 always matches features2. 577 * Hence we enforce that here rather than having to remember to do it 578 * everywhere else that updates features2. 579 */ 580 from->sb_bad_features2 = from->sb_features2; 581 to->sb_features2 = cpu_to_be32(from->sb_features2); 582 to->sb_bad_features2 = cpu_to_be32(from->sb_bad_features2); 583 584 if (xfs_sb_version_hascrc(from)) { 585 to->sb_features_compat = cpu_to_be32(from->sb_features_compat); 586 to->sb_features_ro_compat = 587 cpu_to_be32(from->sb_features_ro_compat); 588 to->sb_features_incompat = 589 cpu_to_be32(from->sb_features_incompat); 590 to->sb_features_log_incompat = 591 cpu_to_be32(from->sb_features_log_incompat); 592 to->sb_spino_align = cpu_to_be32(from->sb_spino_align); 593 to->sb_lsn = cpu_to_be64(from->sb_lsn); 594 if (xfs_sb_version_hasmetauuid(from)) 595 uuid_copy(&to->sb_meta_uuid, &from->sb_meta_uuid); 596 } 597 } 598 599 static int 600 xfs_sb_verify( 601 struct xfs_buf *bp, 602 bool check_version) 603 { 604 struct xfs_mount *mp = bp->b_target->bt_mount; 605 struct xfs_sb sb; 606 607 /* 608 * Use call variant which doesn't convert quota flags from disk 609 * format, because xfs_mount_validate_sb checks the on-disk flags. 610 */ 611 __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); 612 613 /* 614 * Only check the in progress field for the primary superblock as 615 * mkfs.xfs doesn't clear it from secondary superblocks. 616 */ 617 return xfs_mount_validate_sb(mp, &sb, 618 bp->b_maps[0].bm_bn == XFS_SB_DADDR, 619 check_version); 620 } 621 622 /* 623 * If the superblock has the CRC feature bit set or the CRC field is non-null, 624 * check that the CRC is valid. We check the CRC field is non-null because a 625 * single bit error could clear the feature bit and unused parts of the 626 * superblock are supposed to be zero. Hence a non-null crc field indicates that 627 * we've potentially lost a feature bit and we should check it anyway. 628 * 629 * However, past bugs (i.e. in growfs) left non-zeroed regions beyond the 630 * last field in V4 secondary superblocks. So for secondary superblocks, 631 * we are more forgiving, and ignore CRC failures if the primary doesn't 632 * indicate that the fs version is V5. 633 */ 634 static void 635 xfs_sb_read_verify( 636 struct xfs_buf *bp) 637 { 638 struct xfs_mount *mp = bp->b_target->bt_mount; 639 struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp); 640 int error; 641 642 /* 643 * open code the version check to avoid needing to convert the entire 644 * superblock from disk order just to check the version number 645 */ 646 if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC) && 647 (((be16_to_cpu(dsb->sb_versionnum) & XFS_SB_VERSION_NUMBITS) == 648 XFS_SB_VERSION_5) || 649 dsb->sb_crc != 0)) { 650 651 if (!xfs_buf_verify_cksum(bp, XFS_SB_CRC_OFF)) { 652 /* Only fail bad secondaries on a known V5 filesystem */ 653 if (bp->b_bn == XFS_SB_DADDR || 654 xfs_sb_version_hascrc(&mp->m_sb)) { 655 error = -EFSBADCRC; 656 goto out_error; 657 } 658 } 659 } 660 error = xfs_sb_verify(bp, true); 661 662 out_error: 663 if (error == -EFSCORRUPTED || error == -EFSBADCRC) 664 xfs_verifier_error(bp, error, __this_address); 665 else if (error) 666 xfs_buf_ioerror(bp, error); 667 } 668 669 /* 670 * We may be probed for a filesystem match, so we may not want to emit 671 * messages when the superblock buffer is not actually an XFS superblock. 672 * If we find an XFS superblock, then run a normal, noisy mount because we are 673 * really going to mount it and want to know about errors. 674 */ 675 static void 676 xfs_sb_quiet_read_verify( 677 struct xfs_buf *bp) 678 { 679 struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp); 680 681 if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC)) { 682 /* XFS filesystem, verify noisily! */ 683 xfs_sb_read_verify(bp); 684 return; 685 } 686 /* quietly fail */ 687 xfs_buf_ioerror(bp, -EWRONGFS); 688 } 689 690 static void 691 xfs_sb_write_verify( 692 struct xfs_buf *bp) 693 { 694 struct xfs_mount *mp = bp->b_target->bt_mount; 695 struct xfs_buf_log_item *bip = bp->b_log_item; 696 int error; 697 698 error = xfs_sb_verify(bp, false); 699 if (error) { 700 xfs_verifier_error(bp, error, __this_address); 701 return; 702 } 703 704 if (!xfs_sb_version_hascrc(&mp->m_sb)) 705 return; 706 707 if (bip) 708 XFS_BUF_TO_SBP(bp)->sb_lsn = cpu_to_be64(bip->bli_item.li_lsn); 709 710 xfs_buf_update_cksum(bp, XFS_SB_CRC_OFF); 711 } 712 713 const struct xfs_buf_ops xfs_sb_buf_ops = { 714 .name = "xfs_sb", 715 .verify_read = xfs_sb_read_verify, 716 .verify_write = xfs_sb_write_verify, 717 }; 718 719 const struct xfs_buf_ops xfs_sb_quiet_buf_ops = { 720 .name = "xfs_sb_quiet", 721 .verify_read = xfs_sb_quiet_read_verify, 722 .verify_write = xfs_sb_write_verify, 723 }; 724 725 /* 726 * xfs_mount_common 727 * 728 * Mount initialization code establishing various mount 729 * fields from the superblock associated with the given 730 * mount structure 731 */ 732 void 733 xfs_sb_mount_common( 734 struct xfs_mount *mp, 735 struct xfs_sb *sbp) 736 { 737 mp->m_agfrotor = mp->m_agirotor = 0; 738 mp->m_maxagi = mp->m_sb.sb_agcount; 739 mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG; 740 mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT; 741 mp->m_sectbb_log = sbp->sb_sectlog - BBSHIFT; 742 mp->m_agno_log = xfs_highbit32(sbp->sb_agcount - 1) + 1; 743 mp->m_agino_log = sbp->sb_inopblog + sbp->sb_agblklog; 744 mp->m_blockmask = sbp->sb_blocksize - 1; 745 mp->m_blockwsize = sbp->sb_blocksize >> XFS_WORDLOG; 746 mp->m_blockwmask = mp->m_blockwsize - 1; 747 748 mp->m_alloc_mxr[0] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 1); 749 mp->m_alloc_mxr[1] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 0); 750 mp->m_alloc_mnr[0] = mp->m_alloc_mxr[0] / 2; 751 mp->m_alloc_mnr[1] = mp->m_alloc_mxr[1] / 2; 752 753 mp->m_inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1); 754 mp->m_inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0); 755 mp->m_inobt_mnr[0] = mp->m_inobt_mxr[0] / 2; 756 mp->m_inobt_mnr[1] = mp->m_inobt_mxr[1] / 2; 757 758 mp->m_bmap_dmxr[0] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 1); 759 mp->m_bmap_dmxr[1] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 0); 760 mp->m_bmap_dmnr[0] = mp->m_bmap_dmxr[0] / 2; 761 mp->m_bmap_dmnr[1] = mp->m_bmap_dmxr[1] / 2; 762 763 mp->m_rmap_mxr[0] = xfs_rmapbt_maxrecs(sbp->sb_blocksize, 1); 764 mp->m_rmap_mxr[1] = xfs_rmapbt_maxrecs(sbp->sb_blocksize, 0); 765 mp->m_rmap_mnr[0] = mp->m_rmap_mxr[0] / 2; 766 mp->m_rmap_mnr[1] = mp->m_rmap_mxr[1] / 2; 767 768 mp->m_refc_mxr[0] = xfs_refcountbt_maxrecs(sbp->sb_blocksize, true); 769 mp->m_refc_mxr[1] = xfs_refcountbt_maxrecs(sbp->sb_blocksize, false); 770 mp->m_refc_mnr[0] = mp->m_refc_mxr[0] / 2; 771 mp->m_refc_mnr[1] = mp->m_refc_mxr[1] / 2; 772 773 mp->m_bsize = XFS_FSB_TO_BB(mp, 1); 774 mp->m_ialloc_inos = max_t(uint16_t, XFS_INODES_PER_CHUNK, 775 sbp->sb_inopblock); 776 mp->m_ialloc_blks = mp->m_ialloc_inos >> sbp->sb_inopblog; 777 778 if (sbp->sb_spino_align) 779 mp->m_ialloc_min_blks = sbp->sb_spino_align; 780 else 781 mp->m_ialloc_min_blks = mp->m_ialloc_blks; 782 mp->m_alloc_set_aside = xfs_alloc_set_aside(mp); 783 mp->m_ag_max_usable = xfs_alloc_ag_max_usable(mp); 784 } 785 786 /* 787 * xfs_initialize_perag_data 788 * 789 * Read in each per-ag structure so we can count up the number of 790 * allocated inodes, free inodes and used filesystem blocks as this 791 * information is no longer persistent in the superblock. Once we have 792 * this information, write it into the in-core superblock structure. 793 */ 794 int 795 xfs_initialize_perag_data( 796 struct xfs_mount *mp, 797 xfs_agnumber_t agcount) 798 { 799 xfs_agnumber_t index; 800 xfs_perag_t *pag; 801 xfs_sb_t *sbp = &mp->m_sb; 802 uint64_t ifree = 0; 803 uint64_t ialloc = 0; 804 uint64_t bfree = 0; 805 uint64_t bfreelst = 0; 806 uint64_t btree = 0; 807 int error; 808 809 for (index = 0; index < agcount; index++) { 810 /* 811 * read the agf, then the agi. This gets us 812 * all the information we need and populates the 813 * per-ag structures for us. 814 */ 815 error = xfs_alloc_pagf_init(mp, NULL, index, 0); 816 if (error) 817 return error; 818 819 error = xfs_ialloc_pagi_init(mp, NULL, index); 820 if (error) 821 return error; 822 pag = xfs_perag_get(mp, index); 823 ifree += pag->pagi_freecount; 824 ialloc += pag->pagi_count; 825 bfree += pag->pagf_freeblks; 826 bfreelst += pag->pagf_flcount; 827 btree += pag->pagf_btreeblks; 828 xfs_perag_put(pag); 829 } 830 831 /* Overwrite incore superblock counters with just-read data */ 832 spin_lock(&mp->m_sb_lock); 833 sbp->sb_ifree = ifree; 834 sbp->sb_icount = ialloc; 835 sbp->sb_fdblocks = bfree + bfreelst + btree; 836 spin_unlock(&mp->m_sb_lock); 837 838 xfs_reinit_percpu_counters(mp); 839 840 return 0; 841 } 842 843 /* 844 * xfs_log_sb() can be used to copy arbitrary changes to the in-core superblock 845 * into the superblock buffer to be logged. It does not provide the higher 846 * level of locking that is needed to protect the in-core superblock from 847 * concurrent access. 848 */ 849 void 850 xfs_log_sb( 851 struct xfs_trans *tp) 852 { 853 struct xfs_mount *mp = tp->t_mountp; 854 struct xfs_buf *bp = xfs_trans_getsb(tp, mp, 0); 855 856 mp->m_sb.sb_icount = percpu_counter_sum(&mp->m_icount); 857 mp->m_sb.sb_ifree = percpu_counter_sum(&mp->m_ifree); 858 mp->m_sb.sb_fdblocks = percpu_counter_sum(&mp->m_fdblocks); 859 860 xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb); 861 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF); 862 xfs_trans_log_buf(tp, bp, 0, sizeof(struct xfs_dsb)); 863 } 864 865 /* 866 * xfs_sync_sb 867 * 868 * Sync the superblock to disk. 869 * 870 * Note that the caller is responsible for checking the frozen state of the 871 * filesystem. This procedure uses the non-blocking transaction allocator and 872 * thus will allow modifications to a frozen fs. This is required because this 873 * code can be called during the process of freezing where use of the high-level 874 * allocator would deadlock. 875 */ 876 int 877 xfs_sync_sb( 878 struct xfs_mount *mp, 879 bool wait) 880 { 881 struct xfs_trans *tp; 882 int error; 883 884 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_sb, 0, 0, 885 XFS_TRANS_NO_WRITECOUNT, &tp); 886 if (error) 887 return error; 888 889 xfs_log_sb(tp); 890 if (wait) 891 xfs_trans_set_sync(tp); 892 return xfs_trans_commit(tp); 893 } 894 895 /* 896 * Update all the secondary superblocks to match the new state of the primary. 897 * Because we are completely overwriting all the existing fields in the 898 * secondary superblock buffers, there is no need to read them in from disk. 899 * Just get a new buffer, stamp it and write it. 900 * 901 * The sb buffers need to be cached here so that we serialise against other 902 * operations that access the secondary superblocks, but we don't want to keep 903 * them in memory once it is written so we mark it as a one-shot buffer. 904 */ 905 int 906 xfs_update_secondary_sbs( 907 struct xfs_mount *mp) 908 { 909 xfs_agnumber_t agno; 910 int saved_error = 0; 911 int error = 0; 912 LIST_HEAD (buffer_list); 913 914 /* update secondary superblocks. */ 915 for (agno = 1; agno < mp->m_sb.sb_agcount; agno++) { 916 struct xfs_buf *bp; 917 918 bp = xfs_buf_get(mp->m_ddev_targp, 919 XFS_AG_DADDR(mp, agno, XFS_SB_DADDR), 920 XFS_FSS_TO_BB(mp, 1), 0); 921 /* 922 * If we get an error reading or writing alternate superblocks, 923 * continue. xfs_repair chooses the "best" superblock based 924 * on most matches; if we break early, we'll leave more 925 * superblocks un-updated than updated, and xfs_repair may 926 * pick them over the properly-updated primary. 927 */ 928 if (!bp) { 929 xfs_warn(mp, 930 "error allocating secondary superblock for ag %d", 931 agno); 932 if (!saved_error) 933 saved_error = -ENOMEM; 934 continue; 935 } 936 937 bp->b_ops = &xfs_sb_buf_ops; 938 xfs_buf_oneshot(bp); 939 xfs_buf_zero(bp, 0, BBTOB(bp->b_length)); 940 xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb); 941 xfs_buf_delwri_queue(bp, &buffer_list); 942 xfs_buf_relse(bp); 943 944 /* don't hold too many buffers at once */ 945 if (agno % 16) 946 continue; 947 948 error = xfs_buf_delwri_submit(&buffer_list); 949 if (error) { 950 xfs_warn(mp, 951 "write error %d updating a secondary superblock near ag %d", 952 error, agno); 953 if (!saved_error) 954 saved_error = error; 955 continue; 956 } 957 } 958 error = xfs_buf_delwri_submit(&buffer_list); 959 if (error) { 960 xfs_warn(mp, 961 "write error %d updating a secondary superblock near ag %d", 962 error, agno); 963 } 964 965 return saved_error ? saved_error : error; 966 } 967 968 /* 969 * Same behavior as xfs_sync_sb, except that it is always synchronous and it 970 * also writes the superblock buffer to disk sector 0 immediately. 971 */ 972 int 973 xfs_sync_sb_buf( 974 struct xfs_mount *mp) 975 { 976 struct xfs_trans *tp; 977 struct xfs_buf *bp; 978 int error; 979 980 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_sb, 0, 0, 0, &tp); 981 if (error) 982 return error; 983 984 bp = xfs_trans_getsb(tp, mp, 0); 985 xfs_log_sb(tp); 986 xfs_trans_bhold(tp, bp); 987 xfs_trans_set_sync(tp); 988 error = xfs_trans_commit(tp); 989 if (error) 990 goto out; 991 /* 992 * write out the sb buffer to get the changes to disk 993 */ 994 error = xfs_bwrite(bp); 995 out: 996 xfs_buf_relse(bp); 997 return error; 998 } 999 1000 int 1001 xfs_fs_geometry( 1002 struct xfs_sb *sbp, 1003 struct xfs_fsop_geom *geo, 1004 int struct_version) 1005 { 1006 memset(geo, 0, sizeof(struct xfs_fsop_geom)); 1007 1008 geo->blocksize = sbp->sb_blocksize; 1009 geo->rtextsize = sbp->sb_rextsize; 1010 geo->agblocks = sbp->sb_agblocks; 1011 geo->agcount = sbp->sb_agcount; 1012 geo->logblocks = sbp->sb_logblocks; 1013 geo->sectsize = sbp->sb_sectsize; 1014 geo->inodesize = sbp->sb_inodesize; 1015 geo->imaxpct = sbp->sb_imax_pct; 1016 geo->datablocks = sbp->sb_dblocks; 1017 geo->rtblocks = sbp->sb_rblocks; 1018 geo->rtextents = sbp->sb_rextents; 1019 geo->logstart = sbp->sb_logstart; 1020 BUILD_BUG_ON(sizeof(geo->uuid) != sizeof(sbp->sb_uuid)); 1021 memcpy(geo->uuid, &sbp->sb_uuid, sizeof(sbp->sb_uuid)); 1022 1023 if (struct_version < 2) 1024 return 0; 1025 1026 geo->sunit = sbp->sb_unit; 1027 geo->swidth = sbp->sb_width; 1028 1029 if (struct_version < 3) 1030 return 0; 1031 1032 geo->version = XFS_FSOP_GEOM_VERSION; 1033 geo->flags = XFS_FSOP_GEOM_FLAGS_NLINK | 1034 XFS_FSOP_GEOM_FLAGS_DIRV2; 1035 if (xfs_sb_version_hasattr(sbp)) 1036 geo->flags |= XFS_FSOP_GEOM_FLAGS_ATTR; 1037 if (xfs_sb_version_hasquota(sbp)) 1038 geo->flags |= XFS_FSOP_GEOM_FLAGS_QUOTA; 1039 if (xfs_sb_version_hasalign(sbp)) 1040 geo->flags |= XFS_FSOP_GEOM_FLAGS_IALIGN; 1041 if (xfs_sb_version_hasdalign(sbp)) 1042 geo->flags |= XFS_FSOP_GEOM_FLAGS_DALIGN; 1043 if (xfs_sb_version_hasextflgbit(sbp)) 1044 geo->flags |= XFS_FSOP_GEOM_FLAGS_EXTFLG; 1045 if (xfs_sb_version_hassector(sbp)) 1046 geo->flags |= XFS_FSOP_GEOM_FLAGS_SECTOR; 1047 if (xfs_sb_version_hasasciici(sbp)) 1048 geo->flags |= XFS_FSOP_GEOM_FLAGS_DIRV2CI; 1049 if (xfs_sb_version_haslazysbcount(sbp)) 1050 geo->flags |= XFS_FSOP_GEOM_FLAGS_LAZYSB; 1051 if (xfs_sb_version_hasattr2(sbp)) 1052 geo->flags |= XFS_FSOP_GEOM_FLAGS_ATTR2; 1053 if (xfs_sb_version_hasprojid32bit(sbp)) 1054 geo->flags |= XFS_FSOP_GEOM_FLAGS_PROJID32; 1055 if (xfs_sb_version_hascrc(sbp)) 1056 geo->flags |= XFS_FSOP_GEOM_FLAGS_V5SB; 1057 if (xfs_sb_version_hasftype(sbp)) 1058 geo->flags |= XFS_FSOP_GEOM_FLAGS_FTYPE; 1059 if (xfs_sb_version_hasfinobt(sbp)) 1060 geo->flags |= XFS_FSOP_GEOM_FLAGS_FINOBT; 1061 if (xfs_sb_version_hassparseinodes(sbp)) 1062 geo->flags |= XFS_FSOP_GEOM_FLAGS_SPINODES; 1063 if (xfs_sb_version_hasrmapbt(sbp)) 1064 geo->flags |= XFS_FSOP_GEOM_FLAGS_RMAPBT; 1065 if (xfs_sb_version_hasreflink(sbp)) 1066 geo->flags |= XFS_FSOP_GEOM_FLAGS_REFLINK; 1067 if (xfs_sb_version_hassector(sbp)) 1068 geo->logsectsize = sbp->sb_logsectsize; 1069 else 1070 geo->logsectsize = BBSIZE; 1071 geo->rtsectsize = sbp->sb_blocksize; 1072 geo->dirblocksize = xfs_dir2_dirblock_bytes(sbp); 1073 1074 if (struct_version < 4) 1075 return 0; 1076 1077 if (xfs_sb_version_haslogv2(sbp)) 1078 geo->flags |= XFS_FSOP_GEOM_FLAGS_LOGV2; 1079 1080 geo->logsunit = sbp->sb_logsunit; 1081 1082 return 0; 1083 } 1084 1085 /* Read a secondary superblock. */ 1086 int 1087 xfs_sb_read_secondary( 1088 struct xfs_mount *mp, 1089 struct xfs_trans *tp, 1090 xfs_agnumber_t agno, 1091 struct xfs_buf **bpp) 1092 { 1093 struct xfs_buf *bp; 1094 int error; 1095 1096 ASSERT(agno != 0 && agno != NULLAGNUMBER); 1097 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, 1098 XFS_AG_DADDR(mp, agno, XFS_SB_BLOCK(mp)), 1099 XFS_FSS_TO_BB(mp, 1), 0, &bp, &xfs_sb_buf_ops); 1100 if (error) 1101 return error; 1102 xfs_buf_set_ref(bp, XFS_SSB_REF); 1103 *bpp = bp; 1104 return 0; 1105 } 1106 1107 /* Get an uninitialised secondary superblock buffer. */ 1108 int 1109 xfs_sb_get_secondary( 1110 struct xfs_mount *mp, 1111 struct xfs_trans *tp, 1112 xfs_agnumber_t agno, 1113 struct xfs_buf **bpp) 1114 { 1115 struct xfs_buf *bp; 1116 1117 ASSERT(agno != 0 && agno != NULLAGNUMBER); 1118 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, 1119 XFS_AG_DADDR(mp, agno, XFS_SB_BLOCK(mp)), 1120 XFS_FSS_TO_BB(mp, 1), 0); 1121 if (!bp) 1122 return -ENOMEM; 1123 bp->b_ops = &xfs_sb_buf_ops; 1124 xfs_buf_oneshot(bp); 1125 *bpp = bp; 1126 return 0; 1127 } 1128