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_shared.h" 21 #include "xfs_format.h" 22 #include "xfs_log_format.h" 23 #include "xfs_trans_resv.h" 24 #include "xfs_bit.h" 25 #include "xfs_sb.h" 26 #include "xfs_mount.h" 27 #include "xfs_inode.h" 28 #include "xfs_ialloc.h" 29 #include "xfs_alloc.h" 30 #include "xfs_error.h" 31 #include "xfs_trace.h" 32 #include "xfs_cksum.h" 33 #include "xfs_trans.h" 34 #include "xfs_buf_item.h" 35 #include "xfs_bmap_btree.h" 36 #include "xfs_alloc_btree.h" 37 #include "xfs_ialloc_btree.h" 38 39 /* 40 * Physical superblock buffer manipulations. Shared with libxfs in userspace. 41 */ 42 43 /* 44 * Reference counting access wrappers to the perag structures. 45 * Because we never free per-ag structures, the only thing we 46 * have to protect against changes is the tree structure itself. 47 */ 48 struct xfs_perag * 49 xfs_perag_get( 50 struct xfs_mount *mp, 51 xfs_agnumber_t agno) 52 { 53 struct xfs_perag *pag; 54 int ref = 0; 55 56 rcu_read_lock(); 57 pag = radix_tree_lookup(&mp->m_perag_tree, agno); 58 if (pag) { 59 ASSERT(atomic_read(&pag->pag_ref) >= 0); 60 ref = atomic_inc_return(&pag->pag_ref); 61 } 62 rcu_read_unlock(); 63 trace_xfs_perag_get(mp, agno, ref, _RET_IP_); 64 return pag; 65 } 66 67 /* 68 * search from @first to find the next perag with the given tag set. 69 */ 70 struct xfs_perag * 71 xfs_perag_get_tag( 72 struct xfs_mount *mp, 73 xfs_agnumber_t first, 74 int tag) 75 { 76 struct xfs_perag *pag; 77 int found; 78 int ref; 79 80 rcu_read_lock(); 81 found = radix_tree_gang_lookup_tag(&mp->m_perag_tree, 82 (void **)&pag, first, 1, tag); 83 if (found <= 0) { 84 rcu_read_unlock(); 85 return NULL; 86 } 87 ref = atomic_inc_return(&pag->pag_ref); 88 rcu_read_unlock(); 89 trace_xfs_perag_get_tag(mp, pag->pag_agno, ref, _RET_IP_); 90 return pag; 91 } 92 93 void 94 xfs_perag_put( 95 struct xfs_perag *pag) 96 { 97 int ref; 98 99 ASSERT(atomic_read(&pag->pag_ref) > 0); 100 ref = atomic_dec_return(&pag->pag_ref); 101 trace_xfs_perag_put(pag->pag_mount, pag->pag_agno, ref, _RET_IP_); 102 } 103 104 /* 105 * Check the validity of the SB found. 106 */ 107 STATIC int 108 xfs_mount_validate_sb( 109 xfs_mount_t *mp, 110 xfs_sb_t *sbp, 111 bool check_inprogress, 112 bool check_version) 113 { 114 115 /* 116 * If the log device and data device have the 117 * same device number, the log is internal. 118 * Consequently, the sb_logstart should be non-zero. If 119 * we have a zero sb_logstart in this case, we may be trying to mount 120 * a volume filesystem in a non-volume manner. 121 */ 122 if (sbp->sb_magicnum != XFS_SB_MAGIC) { 123 xfs_warn(mp, "bad magic number"); 124 return -EWRONGFS; 125 } 126 127 128 if (!xfs_sb_good_version(sbp)) { 129 xfs_warn(mp, "bad version"); 130 return -EWRONGFS; 131 } 132 133 /* 134 * Version 5 superblock feature mask validation. Reject combinations the 135 * kernel cannot support up front before checking anything else. For 136 * write validation, we don't need to check feature masks. 137 */ 138 if (check_version && XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) { 139 if (xfs_sb_has_compat_feature(sbp, 140 XFS_SB_FEAT_COMPAT_UNKNOWN)) { 141 xfs_warn(mp, 142 "Superblock has unknown compatible features (0x%x) enabled.\n" 143 "Using a more recent kernel is recommended.", 144 (sbp->sb_features_compat & 145 XFS_SB_FEAT_COMPAT_UNKNOWN)); 146 } 147 148 if (xfs_sb_has_ro_compat_feature(sbp, 149 XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) { 150 xfs_alert(mp, 151 "Superblock has unknown read-only compatible features (0x%x) enabled.", 152 (sbp->sb_features_ro_compat & 153 XFS_SB_FEAT_RO_COMPAT_UNKNOWN)); 154 if (!(mp->m_flags & XFS_MOUNT_RDONLY)) { 155 xfs_warn(mp, 156 "Attempted to mount read-only compatible filesystem read-write.\n" 157 "Filesystem can only be safely mounted read only."); 158 return -EINVAL; 159 } 160 } 161 if (xfs_sb_has_incompat_feature(sbp, 162 XFS_SB_FEAT_INCOMPAT_UNKNOWN)) { 163 xfs_warn(mp, 164 "Superblock has unknown incompatible features (0x%x) enabled.\n" 165 "Filesystem can not be safely mounted by this kernel.", 166 (sbp->sb_features_incompat & 167 XFS_SB_FEAT_INCOMPAT_UNKNOWN)); 168 return -EINVAL; 169 } 170 } 171 172 if (xfs_sb_version_has_pquotino(sbp)) { 173 if (sbp->sb_qflags & (XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD)) { 174 xfs_notice(mp, 175 "Version 5 of Super block has XFS_OQUOTA bits."); 176 return -EFSCORRUPTED; 177 } 178 } else if (sbp->sb_qflags & (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD | 179 XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD)) { 180 xfs_notice(mp, 181 "Superblock earlier than Version 5 has XFS_[PQ]UOTA_{ENFD|CHKD} bits."); 182 return -EFSCORRUPTED; 183 } 184 185 if (unlikely( 186 sbp->sb_logstart == 0 && mp->m_logdev_targp == mp->m_ddev_targp)) { 187 xfs_warn(mp, 188 "filesystem is marked as having an external log; " 189 "specify logdev on the mount command line."); 190 return -EINVAL; 191 } 192 193 if (unlikely( 194 sbp->sb_logstart != 0 && mp->m_logdev_targp != mp->m_ddev_targp)) { 195 xfs_warn(mp, 196 "filesystem is marked as having an internal log; " 197 "do not specify logdev on the mount command line."); 198 return -EINVAL; 199 } 200 201 /* 202 * More sanity checking. Most of these were stolen directly from 203 * xfs_repair. 204 */ 205 if (unlikely( 206 sbp->sb_agcount <= 0 || 207 sbp->sb_sectsize < XFS_MIN_SECTORSIZE || 208 sbp->sb_sectsize > XFS_MAX_SECTORSIZE || 209 sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG || 210 sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG || 211 sbp->sb_sectsize != (1 << sbp->sb_sectlog) || 212 sbp->sb_blocksize < XFS_MIN_BLOCKSIZE || 213 sbp->sb_blocksize > XFS_MAX_BLOCKSIZE || 214 sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG || 215 sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG || 216 sbp->sb_blocksize != (1 << sbp->sb_blocklog) || 217 sbp->sb_dirblklog > XFS_MAX_BLOCKSIZE_LOG || 218 sbp->sb_inodesize < XFS_DINODE_MIN_SIZE || 219 sbp->sb_inodesize > XFS_DINODE_MAX_SIZE || 220 sbp->sb_inodelog < XFS_DINODE_MIN_LOG || 221 sbp->sb_inodelog > XFS_DINODE_MAX_LOG || 222 sbp->sb_inodesize != (1 << sbp->sb_inodelog) || 223 sbp->sb_logsunit > XLOG_MAX_RECORD_BSIZE || 224 sbp->sb_inopblock != howmany(sbp->sb_blocksize,sbp->sb_inodesize) || 225 (sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog) || 226 (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE) || 227 (sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE) || 228 (sbp->sb_imax_pct > 100 /* zero sb_imax_pct is valid */) || 229 sbp->sb_dblocks == 0 || 230 sbp->sb_dblocks > XFS_MAX_DBLOCKS(sbp) || 231 sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp) || 232 sbp->sb_shared_vn != 0)) { 233 xfs_notice(mp, "SB sanity check failed"); 234 return -EFSCORRUPTED; 235 } 236 237 /* 238 * Until this is fixed only page-sized or smaller data blocks work. 239 */ 240 if (unlikely(sbp->sb_blocksize > PAGE_SIZE)) { 241 xfs_warn(mp, 242 "File system with blocksize %d bytes. " 243 "Only pagesize (%ld) or less will currently work.", 244 sbp->sb_blocksize, PAGE_SIZE); 245 return -ENOSYS; 246 } 247 248 /* 249 * Currently only very few inode sizes are supported. 250 */ 251 switch (sbp->sb_inodesize) { 252 case 256: 253 case 512: 254 case 1024: 255 case 2048: 256 break; 257 default: 258 xfs_warn(mp, "inode size of %d bytes not supported", 259 sbp->sb_inodesize); 260 return -ENOSYS; 261 } 262 263 if (xfs_sb_validate_fsb_count(sbp, sbp->sb_dblocks) || 264 xfs_sb_validate_fsb_count(sbp, sbp->sb_rblocks)) { 265 xfs_warn(mp, 266 "file system too large to be mounted on this system."); 267 return -EFBIG; 268 } 269 270 if (check_inprogress && sbp->sb_inprogress) { 271 xfs_warn(mp, "Offline file system operation in progress!"); 272 return -EFSCORRUPTED; 273 } 274 return 0; 275 } 276 277 void 278 xfs_sb_quota_from_disk(struct xfs_sb *sbp) 279 { 280 /* 281 * older mkfs doesn't initialize quota inodes to NULLFSINO. This 282 * leads to in-core values having two different values for a quota 283 * inode to be invalid: 0 and NULLFSINO. Change it to a single value 284 * NULLFSINO. 285 * 286 * Note that this change affect only the in-core values. These 287 * values are not written back to disk unless any quota information 288 * is written to the disk. Even in that case, sb_pquotino field is 289 * not written to disk unless the superblock supports pquotino. 290 */ 291 if (sbp->sb_uquotino == 0) 292 sbp->sb_uquotino = NULLFSINO; 293 if (sbp->sb_gquotino == 0) 294 sbp->sb_gquotino = NULLFSINO; 295 if (sbp->sb_pquotino == 0) 296 sbp->sb_pquotino = NULLFSINO; 297 298 /* 299 * We need to do these manipilations only if we are working 300 * with an older version of on-disk superblock. 301 */ 302 if (xfs_sb_version_has_pquotino(sbp)) 303 return; 304 305 if (sbp->sb_qflags & XFS_OQUOTA_ENFD) 306 sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ? 307 XFS_PQUOTA_ENFD : XFS_GQUOTA_ENFD; 308 if (sbp->sb_qflags & XFS_OQUOTA_CHKD) 309 sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ? 310 XFS_PQUOTA_CHKD : XFS_GQUOTA_CHKD; 311 sbp->sb_qflags &= ~(XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD); 312 313 if (sbp->sb_qflags & XFS_PQUOTA_ACCT) { 314 /* 315 * In older version of superblock, on-disk superblock only 316 * has sb_gquotino, and in-core superblock has both sb_gquotino 317 * and sb_pquotino. But, only one of them is supported at any 318 * point of time. So, if PQUOTA is set in disk superblock, 319 * copy over sb_gquotino to sb_pquotino. 320 */ 321 sbp->sb_pquotino = sbp->sb_gquotino; 322 sbp->sb_gquotino = NULLFSINO; 323 } 324 } 325 326 static void 327 __xfs_sb_from_disk( 328 struct xfs_sb *to, 329 xfs_dsb_t *from, 330 bool convert_xquota) 331 { 332 to->sb_magicnum = be32_to_cpu(from->sb_magicnum); 333 to->sb_blocksize = be32_to_cpu(from->sb_blocksize); 334 to->sb_dblocks = be64_to_cpu(from->sb_dblocks); 335 to->sb_rblocks = be64_to_cpu(from->sb_rblocks); 336 to->sb_rextents = be64_to_cpu(from->sb_rextents); 337 memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid)); 338 to->sb_logstart = be64_to_cpu(from->sb_logstart); 339 to->sb_rootino = be64_to_cpu(from->sb_rootino); 340 to->sb_rbmino = be64_to_cpu(from->sb_rbmino); 341 to->sb_rsumino = be64_to_cpu(from->sb_rsumino); 342 to->sb_rextsize = be32_to_cpu(from->sb_rextsize); 343 to->sb_agblocks = be32_to_cpu(from->sb_agblocks); 344 to->sb_agcount = be32_to_cpu(from->sb_agcount); 345 to->sb_rbmblocks = be32_to_cpu(from->sb_rbmblocks); 346 to->sb_logblocks = be32_to_cpu(from->sb_logblocks); 347 to->sb_versionnum = be16_to_cpu(from->sb_versionnum); 348 to->sb_sectsize = be16_to_cpu(from->sb_sectsize); 349 to->sb_inodesize = be16_to_cpu(from->sb_inodesize); 350 to->sb_inopblock = be16_to_cpu(from->sb_inopblock); 351 memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname)); 352 to->sb_blocklog = from->sb_blocklog; 353 to->sb_sectlog = from->sb_sectlog; 354 to->sb_inodelog = from->sb_inodelog; 355 to->sb_inopblog = from->sb_inopblog; 356 to->sb_agblklog = from->sb_agblklog; 357 to->sb_rextslog = from->sb_rextslog; 358 to->sb_inprogress = from->sb_inprogress; 359 to->sb_imax_pct = from->sb_imax_pct; 360 to->sb_icount = be64_to_cpu(from->sb_icount); 361 to->sb_ifree = be64_to_cpu(from->sb_ifree); 362 to->sb_fdblocks = be64_to_cpu(from->sb_fdblocks); 363 to->sb_frextents = be64_to_cpu(from->sb_frextents); 364 to->sb_uquotino = be64_to_cpu(from->sb_uquotino); 365 to->sb_gquotino = be64_to_cpu(from->sb_gquotino); 366 to->sb_qflags = be16_to_cpu(from->sb_qflags); 367 to->sb_flags = from->sb_flags; 368 to->sb_shared_vn = from->sb_shared_vn; 369 to->sb_inoalignmt = be32_to_cpu(from->sb_inoalignmt); 370 to->sb_unit = be32_to_cpu(from->sb_unit); 371 to->sb_width = be32_to_cpu(from->sb_width); 372 to->sb_dirblklog = from->sb_dirblklog; 373 to->sb_logsectlog = from->sb_logsectlog; 374 to->sb_logsectsize = be16_to_cpu(from->sb_logsectsize); 375 to->sb_logsunit = be32_to_cpu(from->sb_logsunit); 376 to->sb_features2 = be32_to_cpu(from->sb_features2); 377 to->sb_bad_features2 = be32_to_cpu(from->sb_bad_features2); 378 to->sb_features_compat = be32_to_cpu(from->sb_features_compat); 379 to->sb_features_ro_compat = be32_to_cpu(from->sb_features_ro_compat); 380 to->sb_features_incompat = be32_to_cpu(from->sb_features_incompat); 381 to->sb_features_log_incompat = 382 be32_to_cpu(from->sb_features_log_incompat); 383 /* crc is only used on disk, not in memory; just init to 0 here. */ 384 to->sb_crc = 0; 385 to->sb_pad = 0; 386 to->sb_pquotino = be64_to_cpu(from->sb_pquotino); 387 to->sb_lsn = be64_to_cpu(from->sb_lsn); 388 /* Convert on-disk flags to in-memory flags? */ 389 if (convert_xquota) 390 xfs_sb_quota_from_disk(to); 391 } 392 393 void 394 xfs_sb_from_disk( 395 struct xfs_sb *to, 396 xfs_dsb_t *from) 397 { 398 __xfs_sb_from_disk(to, from, true); 399 } 400 401 static void 402 xfs_sb_quota_to_disk( 403 struct xfs_dsb *to, 404 struct xfs_sb *from) 405 { 406 __uint16_t qflags = from->sb_qflags; 407 408 to->sb_uquotino = cpu_to_be64(from->sb_uquotino); 409 if (xfs_sb_version_has_pquotino(from)) { 410 to->sb_qflags = cpu_to_be16(from->sb_qflags); 411 to->sb_gquotino = cpu_to_be64(from->sb_gquotino); 412 to->sb_pquotino = cpu_to_be64(from->sb_pquotino); 413 return; 414 } 415 416 /* 417 * The in-core version of sb_qflags do not have XFS_OQUOTA_* 418 * flags, whereas the on-disk version does. So, convert incore 419 * XFS_{PG}QUOTA_* flags to on-disk XFS_OQUOTA_* flags. 420 */ 421 qflags &= ~(XFS_PQUOTA_ENFD | XFS_PQUOTA_CHKD | 422 XFS_GQUOTA_ENFD | XFS_GQUOTA_CHKD); 423 424 if (from->sb_qflags & 425 (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD)) 426 qflags |= XFS_OQUOTA_ENFD; 427 if (from->sb_qflags & 428 (XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD)) 429 qflags |= XFS_OQUOTA_CHKD; 430 to->sb_qflags = cpu_to_be16(qflags); 431 432 /* 433 * GQUOTINO and PQUOTINO cannot be used together in versions 434 * of superblock that do not have pquotino. from->sb_flags 435 * tells us which quota is active and should be copied to 436 * disk. If neither are active, we should NULL the inode. 437 * 438 * In all cases, the separate pquotino must remain 0 because it 439 * it beyond the "end" of the valid non-pquotino superblock. 440 */ 441 if (from->sb_qflags & XFS_GQUOTA_ACCT) 442 to->sb_gquotino = cpu_to_be64(from->sb_gquotino); 443 else if (from->sb_qflags & XFS_PQUOTA_ACCT) 444 to->sb_gquotino = cpu_to_be64(from->sb_pquotino); 445 else { 446 /* 447 * We can't rely on just the fields being logged to tell us 448 * that it is safe to write NULLFSINO - we should only do that 449 * if quotas are not actually enabled. Hence only write 450 * NULLFSINO if both in-core quota inodes are NULL. 451 */ 452 if (from->sb_gquotino == NULLFSINO && 453 from->sb_pquotino == NULLFSINO) 454 to->sb_gquotino = cpu_to_be64(NULLFSINO); 455 } 456 457 to->sb_pquotino = 0; 458 } 459 460 void 461 xfs_sb_to_disk( 462 struct xfs_dsb *to, 463 struct xfs_sb *from) 464 { 465 xfs_sb_quota_to_disk(to, from); 466 467 to->sb_magicnum = cpu_to_be32(from->sb_magicnum); 468 to->sb_blocksize = cpu_to_be32(from->sb_blocksize); 469 to->sb_dblocks = cpu_to_be64(from->sb_dblocks); 470 to->sb_rblocks = cpu_to_be64(from->sb_rblocks); 471 to->sb_rextents = cpu_to_be64(from->sb_rextents); 472 memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid)); 473 to->sb_logstart = cpu_to_be64(from->sb_logstart); 474 to->sb_rootino = cpu_to_be64(from->sb_rootino); 475 to->sb_rbmino = cpu_to_be64(from->sb_rbmino); 476 to->sb_rsumino = cpu_to_be64(from->sb_rsumino); 477 to->sb_rextsize = cpu_to_be32(from->sb_rextsize); 478 to->sb_agblocks = cpu_to_be32(from->sb_agblocks); 479 to->sb_agcount = cpu_to_be32(from->sb_agcount); 480 to->sb_rbmblocks = cpu_to_be32(from->sb_rbmblocks); 481 to->sb_logblocks = cpu_to_be32(from->sb_logblocks); 482 to->sb_versionnum = cpu_to_be16(from->sb_versionnum); 483 to->sb_sectsize = cpu_to_be16(from->sb_sectsize); 484 to->sb_inodesize = cpu_to_be16(from->sb_inodesize); 485 to->sb_inopblock = cpu_to_be16(from->sb_inopblock); 486 memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname)); 487 to->sb_blocklog = from->sb_blocklog; 488 to->sb_sectlog = from->sb_sectlog; 489 to->sb_inodelog = from->sb_inodelog; 490 to->sb_inopblog = from->sb_inopblog; 491 to->sb_agblklog = from->sb_agblklog; 492 to->sb_rextslog = from->sb_rextslog; 493 to->sb_inprogress = from->sb_inprogress; 494 to->sb_imax_pct = from->sb_imax_pct; 495 to->sb_icount = cpu_to_be64(from->sb_icount); 496 to->sb_ifree = cpu_to_be64(from->sb_ifree); 497 to->sb_fdblocks = cpu_to_be64(from->sb_fdblocks); 498 to->sb_frextents = cpu_to_be64(from->sb_frextents); 499 500 to->sb_flags = from->sb_flags; 501 to->sb_shared_vn = from->sb_shared_vn; 502 to->sb_inoalignmt = cpu_to_be32(from->sb_inoalignmt); 503 to->sb_unit = cpu_to_be32(from->sb_unit); 504 to->sb_width = cpu_to_be32(from->sb_width); 505 to->sb_dirblklog = from->sb_dirblklog; 506 to->sb_logsectlog = from->sb_logsectlog; 507 to->sb_logsectsize = cpu_to_be16(from->sb_logsectsize); 508 to->sb_logsunit = cpu_to_be32(from->sb_logsunit); 509 510 /* 511 * We need to ensure that bad_features2 always matches features2. 512 * Hence we enforce that here rather than having to remember to do it 513 * everywhere else that updates features2. 514 */ 515 from->sb_bad_features2 = from->sb_features2; 516 to->sb_features2 = cpu_to_be32(from->sb_features2); 517 to->sb_bad_features2 = cpu_to_be32(from->sb_bad_features2); 518 519 if (xfs_sb_version_hascrc(from)) { 520 to->sb_features_compat = cpu_to_be32(from->sb_features_compat); 521 to->sb_features_ro_compat = 522 cpu_to_be32(from->sb_features_ro_compat); 523 to->sb_features_incompat = 524 cpu_to_be32(from->sb_features_incompat); 525 to->sb_features_log_incompat = 526 cpu_to_be32(from->sb_features_log_incompat); 527 to->sb_pad = 0; 528 to->sb_lsn = cpu_to_be64(from->sb_lsn); 529 } 530 } 531 532 static int 533 xfs_sb_verify( 534 struct xfs_buf *bp, 535 bool check_version) 536 { 537 struct xfs_mount *mp = bp->b_target->bt_mount; 538 struct xfs_sb sb; 539 540 /* 541 * Use call variant which doesn't convert quota flags from disk 542 * format, because xfs_mount_validate_sb checks the on-disk flags. 543 */ 544 __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false); 545 546 /* 547 * Only check the in progress field for the primary superblock as 548 * mkfs.xfs doesn't clear it from secondary superblocks. 549 */ 550 return xfs_mount_validate_sb(mp, &sb, bp->b_bn == XFS_SB_DADDR, 551 check_version); 552 } 553 554 /* 555 * If the superblock has the CRC feature bit set or the CRC field is non-null, 556 * check that the CRC is valid. We check the CRC field is non-null because a 557 * single bit error could clear the feature bit and unused parts of the 558 * superblock are supposed to be zero. Hence a non-null crc field indicates that 559 * we've potentially lost a feature bit and we should check it anyway. 560 * 561 * However, past bugs (i.e. in growfs) left non-zeroed regions beyond the 562 * last field in V4 secondary superblocks. So for secondary superblocks, 563 * we are more forgiving, and ignore CRC failures if the primary doesn't 564 * indicate that the fs version is V5. 565 */ 566 static void 567 xfs_sb_read_verify( 568 struct xfs_buf *bp) 569 { 570 struct xfs_mount *mp = bp->b_target->bt_mount; 571 struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp); 572 int error; 573 574 /* 575 * open code the version check to avoid needing to convert the entire 576 * superblock from disk order just to check the version number 577 */ 578 if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC) && 579 (((be16_to_cpu(dsb->sb_versionnum) & XFS_SB_VERSION_NUMBITS) == 580 XFS_SB_VERSION_5) || 581 dsb->sb_crc != 0)) { 582 583 if (!xfs_buf_verify_cksum(bp, XFS_SB_CRC_OFF)) { 584 /* Only fail bad secondaries on a known V5 filesystem */ 585 if (bp->b_bn == XFS_SB_DADDR || 586 xfs_sb_version_hascrc(&mp->m_sb)) { 587 error = -EFSBADCRC; 588 goto out_error; 589 } 590 } 591 } 592 error = xfs_sb_verify(bp, true); 593 594 out_error: 595 if (error) { 596 xfs_buf_ioerror(bp, error); 597 if (error == -EFSCORRUPTED || error == -EFSBADCRC) 598 xfs_verifier_error(bp); 599 } 600 } 601 602 /* 603 * We may be probed for a filesystem match, so we may not want to emit 604 * messages when the superblock buffer is not actually an XFS superblock. 605 * If we find an XFS superblock, then run a normal, noisy mount because we are 606 * really going to mount it and want to know about errors. 607 */ 608 static void 609 xfs_sb_quiet_read_verify( 610 struct xfs_buf *bp) 611 { 612 struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp); 613 614 if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC)) { 615 /* XFS filesystem, verify noisily! */ 616 xfs_sb_read_verify(bp); 617 return; 618 } 619 /* quietly fail */ 620 xfs_buf_ioerror(bp, -EWRONGFS); 621 } 622 623 static void 624 xfs_sb_write_verify( 625 struct xfs_buf *bp) 626 { 627 struct xfs_mount *mp = bp->b_target->bt_mount; 628 struct xfs_buf_log_item *bip = bp->b_fspriv; 629 int error; 630 631 error = xfs_sb_verify(bp, false); 632 if (error) { 633 xfs_buf_ioerror(bp, error); 634 xfs_verifier_error(bp); 635 return; 636 } 637 638 if (!xfs_sb_version_hascrc(&mp->m_sb)) 639 return; 640 641 if (bip) 642 XFS_BUF_TO_SBP(bp)->sb_lsn = cpu_to_be64(bip->bli_item.li_lsn); 643 644 xfs_buf_update_cksum(bp, XFS_SB_CRC_OFF); 645 } 646 647 const struct xfs_buf_ops xfs_sb_buf_ops = { 648 .verify_read = xfs_sb_read_verify, 649 .verify_write = xfs_sb_write_verify, 650 }; 651 652 const struct xfs_buf_ops xfs_sb_quiet_buf_ops = { 653 .verify_read = xfs_sb_quiet_read_verify, 654 .verify_write = xfs_sb_write_verify, 655 }; 656 657 /* 658 * xfs_mount_common 659 * 660 * Mount initialization code establishing various mount 661 * fields from the superblock associated with the given 662 * mount structure 663 */ 664 void 665 xfs_sb_mount_common( 666 struct xfs_mount *mp, 667 struct xfs_sb *sbp) 668 { 669 mp->m_agfrotor = mp->m_agirotor = 0; 670 spin_lock_init(&mp->m_agirotor_lock); 671 mp->m_maxagi = mp->m_sb.sb_agcount; 672 mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG; 673 mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT; 674 mp->m_sectbb_log = sbp->sb_sectlog - BBSHIFT; 675 mp->m_agno_log = xfs_highbit32(sbp->sb_agcount - 1) + 1; 676 mp->m_agino_log = sbp->sb_inopblog + sbp->sb_agblklog; 677 mp->m_blockmask = sbp->sb_blocksize - 1; 678 mp->m_blockwsize = sbp->sb_blocksize >> XFS_WORDLOG; 679 mp->m_blockwmask = mp->m_blockwsize - 1; 680 681 mp->m_alloc_mxr[0] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 1); 682 mp->m_alloc_mxr[1] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 0); 683 mp->m_alloc_mnr[0] = mp->m_alloc_mxr[0] / 2; 684 mp->m_alloc_mnr[1] = mp->m_alloc_mxr[1] / 2; 685 686 mp->m_inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1); 687 mp->m_inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0); 688 mp->m_inobt_mnr[0] = mp->m_inobt_mxr[0] / 2; 689 mp->m_inobt_mnr[1] = mp->m_inobt_mxr[1] / 2; 690 691 mp->m_bmap_dmxr[0] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 1); 692 mp->m_bmap_dmxr[1] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 0); 693 mp->m_bmap_dmnr[0] = mp->m_bmap_dmxr[0] / 2; 694 mp->m_bmap_dmnr[1] = mp->m_bmap_dmxr[1] / 2; 695 696 mp->m_bsize = XFS_FSB_TO_BB(mp, 1); 697 mp->m_ialloc_inos = (int)MAX((__uint16_t)XFS_INODES_PER_CHUNK, 698 sbp->sb_inopblock); 699 mp->m_ialloc_blks = mp->m_ialloc_inos >> sbp->sb_inopblog; 700 } 701 702 /* 703 * xfs_initialize_perag_data 704 * 705 * Read in each per-ag structure so we can count up the number of 706 * allocated inodes, free inodes and used filesystem blocks as this 707 * information is no longer persistent in the superblock. Once we have 708 * this information, write it into the in-core superblock structure. 709 */ 710 int 711 xfs_initialize_perag_data( 712 struct xfs_mount *mp, 713 xfs_agnumber_t agcount) 714 { 715 xfs_agnumber_t index; 716 xfs_perag_t *pag; 717 xfs_sb_t *sbp = &mp->m_sb; 718 uint64_t ifree = 0; 719 uint64_t ialloc = 0; 720 uint64_t bfree = 0; 721 uint64_t bfreelst = 0; 722 uint64_t btree = 0; 723 int error; 724 725 for (index = 0; index < agcount; index++) { 726 /* 727 * read the agf, then the agi. This gets us 728 * all the information we need and populates the 729 * per-ag structures for us. 730 */ 731 error = xfs_alloc_pagf_init(mp, NULL, index, 0); 732 if (error) 733 return error; 734 735 error = xfs_ialloc_pagi_init(mp, NULL, index); 736 if (error) 737 return error; 738 pag = xfs_perag_get(mp, index); 739 ifree += pag->pagi_freecount; 740 ialloc += pag->pagi_count; 741 bfree += pag->pagf_freeblks; 742 bfreelst += pag->pagf_flcount; 743 btree += pag->pagf_btreeblks; 744 xfs_perag_put(pag); 745 } 746 /* 747 * Overwrite incore superblock counters with just-read data 748 */ 749 spin_lock(&mp->m_sb_lock); 750 sbp->sb_ifree = ifree; 751 sbp->sb_icount = ialloc; 752 sbp->sb_fdblocks = bfree + bfreelst + btree; 753 spin_unlock(&mp->m_sb_lock); 754 755 /* Fixup the per-cpu counters as well. */ 756 xfs_icsb_reinit_counters(mp); 757 758 return 0; 759 } 760 761 /* 762 * xfs_log_sb() can be used to copy arbitrary changes to the in-core superblock 763 * into the superblock buffer to be logged. It does not provide the higher 764 * level of locking that is needed to protect the in-core superblock from 765 * concurrent access. 766 */ 767 void 768 xfs_log_sb( 769 struct xfs_trans *tp) 770 { 771 struct xfs_mount *mp = tp->t_mountp; 772 struct xfs_buf *bp = xfs_trans_getsb(tp, mp, 0); 773 774 xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb); 775 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF); 776 xfs_trans_log_buf(tp, bp, 0, sizeof(struct xfs_dsb)); 777 } 778 779 /* 780 * xfs_sync_sb 781 * 782 * Sync the superblock to disk. 783 * 784 * Note that the caller is responsible for checking the frozen state of the 785 * filesystem. This procedure uses the non-blocking transaction allocator and 786 * thus will allow modifications to a frozen fs. This is required because this 787 * code can be called during the process of freezing where use of the high-level 788 * allocator would deadlock. 789 */ 790 int 791 xfs_sync_sb( 792 struct xfs_mount *mp, 793 bool wait) 794 { 795 struct xfs_trans *tp; 796 int error; 797 798 tp = _xfs_trans_alloc(mp, XFS_TRANS_SB_CHANGE, KM_SLEEP); 799 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_sb, 0, 0); 800 if (error) { 801 xfs_trans_cancel(tp, 0); 802 return error; 803 } 804 805 xfs_log_sb(tp); 806 if (wait) 807 xfs_trans_set_sync(tp); 808 return xfs_trans_commit(tp, 0); 809 } 810