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