xref: /openbmc/linux/fs/xfs/libxfs/xfs_sb.c (revision e5242c5f)
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_ialloc.h"
16 #include "xfs_alloc.h"
17 #include "xfs_error.h"
18 #include "xfs_trans.h"
19 #include "xfs_buf_item.h"
20 #include "xfs_bmap_btree.h"
21 #include "xfs_alloc_btree.h"
22 #include "xfs_log.h"
23 #include "xfs_rmap_btree.h"
24 #include "xfs_refcount_btree.h"
25 #include "xfs_da_format.h"
26 #include "xfs_health.h"
27 #include "xfs_ag.h"
28 #include "xfs_rtbitmap.h"
29 
30 /*
31  * Physical superblock buffer manipulations. Shared with libxfs in userspace.
32  */
33 
34 /*
35  * Check that all the V4 feature bits that the V5 filesystem format requires are
36  * correctly set.
37  */
38 static bool
39 xfs_sb_validate_v5_features(
40 	struct xfs_sb	*sbp)
41 {
42 	/* We must not have any unknown V4 feature bits set */
43 	if (sbp->sb_versionnum & ~XFS_SB_VERSION_OKBITS)
44 		return false;
45 
46 	/*
47 	 * The CRC bit is considered an invalid V4 flag, so we have to add it
48 	 * manually to the OKBITS mask.
49 	 */
50 	if (sbp->sb_features2 & ~(XFS_SB_VERSION2_OKBITS |
51 				  XFS_SB_VERSION2_CRCBIT))
52 		return false;
53 
54 	/* Now check all the required V4 feature flags are set. */
55 
56 #define V5_VERS_FLAGS	(XFS_SB_VERSION_NLINKBIT	| \
57 			XFS_SB_VERSION_ALIGNBIT		| \
58 			XFS_SB_VERSION_LOGV2BIT		| \
59 			XFS_SB_VERSION_EXTFLGBIT	| \
60 			XFS_SB_VERSION_DIRV2BIT		| \
61 			XFS_SB_VERSION_MOREBITSBIT)
62 
63 #define V5_FEAT_FLAGS	(XFS_SB_VERSION2_LAZYSBCOUNTBIT	| \
64 			XFS_SB_VERSION2_ATTR2BIT	| \
65 			XFS_SB_VERSION2_PROJID32BIT	| \
66 			XFS_SB_VERSION2_CRCBIT)
67 
68 	if ((sbp->sb_versionnum & V5_VERS_FLAGS) != V5_VERS_FLAGS)
69 		return false;
70 	if ((sbp->sb_features2 & V5_FEAT_FLAGS) != V5_FEAT_FLAGS)
71 		return false;
72 	return true;
73 }
74 
75 /*
76  * We current support XFS v5 formats with known features and v4 superblocks with
77  * at least V2 directories.
78  */
79 bool
80 xfs_sb_good_version(
81 	struct xfs_sb	*sbp)
82 {
83 	/*
84 	 * All v5 filesystems are supported, but we must check that all the
85 	 * required v4 feature flags are enabled correctly as the code checks
86 	 * those flags and not for v5 support.
87 	 */
88 	if (xfs_sb_is_v5(sbp))
89 		return xfs_sb_validate_v5_features(sbp);
90 
91 	/* versions prior to v4 are not supported */
92 	if (XFS_SB_VERSION_NUM(sbp) != XFS_SB_VERSION_4)
93 		return false;
94 
95 	/* We must not have any unknown v4 feature bits set */
96 	if ((sbp->sb_versionnum & ~XFS_SB_VERSION_OKBITS) ||
97 	    ((sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT) &&
98 	     (sbp->sb_features2 & ~XFS_SB_VERSION2_OKBITS)))
99 		return false;
100 
101 	/* V4 filesystems need v2 directories and unwritten extents */
102 	if (!(sbp->sb_versionnum & XFS_SB_VERSION_DIRV2BIT))
103 		return false;
104 	if (!(sbp->sb_versionnum & XFS_SB_VERSION_EXTFLGBIT))
105 		return false;
106 
107 	/* It's a supported v4 filesystem */
108 	return true;
109 }
110 
111 uint64_t
112 xfs_sb_version_to_features(
113 	struct xfs_sb	*sbp)
114 {
115 	uint64_t	features = 0;
116 
117 	/* optional V4 features */
118 	if (sbp->sb_rblocks > 0)
119 		features |= XFS_FEAT_REALTIME;
120 	if (sbp->sb_versionnum & XFS_SB_VERSION_NLINKBIT)
121 		features |= XFS_FEAT_NLINK;
122 	if (sbp->sb_versionnum & XFS_SB_VERSION_ATTRBIT)
123 		features |= XFS_FEAT_ATTR;
124 	if (sbp->sb_versionnum & XFS_SB_VERSION_QUOTABIT)
125 		features |= XFS_FEAT_QUOTA;
126 	if (sbp->sb_versionnum & XFS_SB_VERSION_ALIGNBIT)
127 		features |= XFS_FEAT_ALIGN;
128 	if (sbp->sb_versionnum & XFS_SB_VERSION_LOGV2BIT)
129 		features |= XFS_FEAT_LOGV2;
130 	if (sbp->sb_versionnum & XFS_SB_VERSION_DALIGNBIT)
131 		features |= XFS_FEAT_DALIGN;
132 	if (sbp->sb_versionnum & XFS_SB_VERSION_EXTFLGBIT)
133 		features |= XFS_FEAT_EXTFLG;
134 	if (sbp->sb_versionnum & XFS_SB_VERSION_SECTORBIT)
135 		features |= XFS_FEAT_SECTOR;
136 	if (sbp->sb_versionnum & XFS_SB_VERSION_BORGBIT)
137 		features |= XFS_FEAT_ASCIICI;
138 	if (sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT) {
139 		if (sbp->sb_features2 & XFS_SB_VERSION2_LAZYSBCOUNTBIT)
140 			features |= XFS_FEAT_LAZYSBCOUNT;
141 		if (sbp->sb_features2 & XFS_SB_VERSION2_ATTR2BIT)
142 			features |= XFS_FEAT_ATTR2;
143 		if (sbp->sb_features2 & XFS_SB_VERSION2_PROJID32BIT)
144 			features |= XFS_FEAT_PROJID32;
145 		if (sbp->sb_features2 & XFS_SB_VERSION2_FTYPE)
146 			features |= XFS_FEAT_FTYPE;
147 	}
148 
149 	if (!xfs_sb_is_v5(sbp))
150 		return features;
151 
152 	/* Always on V5 features */
153 	features |= XFS_FEAT_ALIGN | XFS_FEAT_LOGV2 | XFS_FEAT_EXTFLG |
154 		    XFS_FEAT_LAZYSBCOUNT | XFS_FEAT_ATTR2 | XFS_FEAT_PROJID32 |
155 		    XFS_FEAT_V3INODES | XFS_FEAT_CRC | XFS_FEAT_PQUOTINO;
156 
157 	/* Optional V5 features */
158 	if (sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_FINOBT)
159 		features |= XFS_FEAT_FINOBT;
160 	if (sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_RMAPBT)
161 		features |= XFS_FEAT_RMAPBT;
162 	if (sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_REFLINK)
163 		features |= XFS_FEAT_REFLINK;
164 	if (sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_INOBTCNT)
165 		features |= XFS_FEAT_INOBTCNT;
166 	if (sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_FTYPE)
167 		features |= XFS_FEAT_FTYPE;
168 	if (sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_SPINODES)
169 		features |= XFS_FEAT_SPINODES;
170 	if (sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_META_UUID)
171 		features |= XFS_FEAT_META_UUID;
172 	if (sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_BIGTIME)
173 		features |= XFS_FEAT_BIGTIME;
174 	if (sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR)
175 		features |= XFS_FEAT_NEEDSREPAIR;
176 	if (sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_NREXT64)
177 		features |= XFS_FEAT_NREXT64;
178 
179 	return features;
180 }
181 
182 /* Check all the superblock fields we care about when reading one in. */
183 STATIC int
184 xfs_validate_sb_read(
185 	struct xfs_mount	*mp,
186 	struct xfs_sb		*sbp)
187 {
188 	if (!xfs_sb_is_v5(sbp))
189 		return 0;
190 
191 	/*
192 	 * Version 5 superblock feature mask validation. Reject combinations
193 	 * the kernel cannot support up front before checking anything else.
194 	 */
195 	if (xfs_sb_has_compat_feature(sbp, XFS_SB_FEAT_COMPAT_UNKNOWN)) {
196 		xfs_warn(mp,
197 "Superblock has unknown compatible features (0x%x) enabled.",
198 			(sbp->sb_features_compat & XFS_SB_FEAT_COMPAT_UNKNOWN));
199 		xfs_warn(mp,
200 "Using a more recent kernel is recommended.");
201 	}
202 
203 	if (xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
204 		xfs_alert(mp,
205 "Superblock has unknown read-only compatible features (0x%x) enabled.",
206 			(sbp->sb_features_ro_compat &
207 					XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
208 		if (!xfs_is_readonly(mp)) {
209 			xfs_warn(mp,
210 "Attempted to mount read-only compatible filesystem read-write.");
211 			xfs_warn(mp,
212 "Filesystem can only be safely mounted read only.");
213 
214 			return -EINVAL;
215 		}
216 	}
217 	if (xfs_sb_has_incompat_feature(sbp, XFS_SB_FEAT_INCOMPAT_UNKNOWN)) {
218 		xfs_warn(mp,
219 "Superblock has unknown incompatible features (0x%x) enabled.",
220 			(sbp->sb_features_incompat &
221 					XFS_SB_FEAT_INCOMPAT_UNKNOWN));
222 		xfs_warn(mp,
223 "Filesystem cannot be safely mounted by this kernel.");
224 		return -EINVAL;
225 	}
226 
227 	return 0;
228 }
229 
230 /* Check all the superblock fields we care about when writing one out. */
231 STATIC int
232 xfs_validate_sb_write(
233 	struct xfs_mount	*mp,
234 	struct xfs_buf		*bp,
235 	struct xfs_sb		*sbp)
236 {
237 	/*
238 	 * Carry out additional sb summary counter sanity checks when we write
239 	 * the superblock.  We skip this in the read validator because there
240 	 * could be newer superblocks in the log and if the values are garbage
241 	 * even after replay we'll recalculate them at the end of log mount.
242 	 *
243 	 * mkfs has traditionally written zeroed counters to inprogress and
244 	 * secondary superblocks, so allow this usage to continue because
245 	 * we never read counters from such superblocks.
246 	 */
247 	if (xfs_buf_daddr(bp) == XFS_SB_DADDR && !sbp->sb_inprogress &&
248 	    (sbp->sb_fdblocks > sbp->sb_dblocks ||
249 	     !xfs_verify_icount(mp, sbp->sb_icount) ||
250 	     sbp->sb_ifree > sbp->sb_icount)) {
251 		xfs_warn(mp, "SB summary counter sanity check failed");
252 		return -EFSCORRUPTED;
253 	}
254 
255 	if (!xfs_sb_is_v5(sbp))
256 		return 0;
257 
258 	/*
259 	 * Version 5 superblock feature mask validation. Reject combinations
260 	 * the kernel cannot support since we checked for unsupported bits in
261 	 * the read verifier, which means that memory is corrupt.
262 	 */
263 	if (!xfs_is_readonly(mp) &&
264 	    xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
265 		xfs_alert(mp,
266 "Corruption detected in superblock read-only compatible features (0x%x)!",
267 			(sbp->sb_features_ro_compat &
268 					XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
269 		return -EFSCORRUPTED;
270 	}
271 	if (xfs_sb_has_incompat_feature(sbp, XFS_SB_FEAT_INCOMPAT_UNKNOWN)) {
272 		xfs_warn(mp,
273 "Corruption detected in superblock incompatible features (0x%x)!",
274 			(sbp->sb_features_incompat &
275 					XFS_SB_FEAT_INCOMPAT_UNKNOWN));
276 		return -EFSCORRUPTED;
277 	}
278 	if (xfs_sb_has_incompat_log_feature(sbp,
279 			XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN)) {
280 		xfs_warn(mp,
281 "Corruption detected in superblock incompatible log features (0x%x)!",
282 			(sbp->sb_features_log_incompat &
283 					XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
284 		return -EFSCORRUPTED;
285 	}
286 
287 	/*
288 	 * We can't read verify the sb LSN because the read verifier is called
289 	 * before the log is allocated and processed. We know the log is set up
290 	 * before write verifier calls, so check it here.
291 	 */
292 	if (!xfs_log_check_lsn(mp, sbp->sb_lsn))
293 		return -EFSCORRUPTED;
294 
295 	return 0;
296 }
297 
298 /* Check the validity of the SB. */
299 STATIC int
300 xfs_validate_sb_common(
301 	struct xfs_mount	*mp,
302 	struct xfs_buf		*bp,
303 	struct xfs_sb		*sbp)
304 {
305 	struct xfs_dsb		*dsb = bp->b_addr;
306 	uint32_t		agcount = 0;
307 	uint32_t		rem;
308 	bool			has_dalign;
309 
310 	if (!xfs_verify_magic(bp, dsb->sb_magicnum)) {
311 		xfs_warn(mp,
312 "Superblock has bad magic number 0x%x. Not an XFS filesystem?",
313 			be32_to_cpu(dsb->sb_magicnum));
314 		return -EWRONGFS;
315 	}
316 
317 	if (!xfs_sb_good_version(sbp)) {
318 		xfs_warn(mp,
319 "Superblock has unknown features enabled or corrupted feature masks.");
320 		return -EWRONGFS;
321 	}
322 
323 	/*
324 	 * Validate feature flags and state
325 	 */
326 	if (xfs_sb_is_v5(sbp)) {
327 		if (sbp->sb_blocksize < XFS_MIN_CRC_BLOCKSIZE) {
328 			xfs_notice(mp,
329 "Block size (%u bytes) too small for Version 5 superblock (minimum %d bytes)",
330 				sbp->sb_blocksize, XFS_MIN_CRC_BLOCKSIZE);
331 			return -EFSCORRUPTED;
332 		}
333 
334 		/* V5 has a separate project quota inode */
335 		if (sbp->sb_qflags & (XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD)) {
336 			xfs_notice(mp,
337 			   "Version 5 of Super block has XFS_OQUOTA bits.");
338 			return -EFSCORRUPTED;
339 		}
340 
341 		/*
342 		 * Full inode chunks must be aligned to inode chunk size when
343 		 * sparse inodes are enabled to support the sparse chunk
344 		 * allocation algorithm and prevent overlapping inode records.
345 		 */
346 		if (sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_SPINODES) {
347 			uint32_t	align;
348 
349 			align = XFS_INODES_PER_CHUNK * sbp->sb_inodesize
350 					>> sbp->sb_blocklog;
351 			if (sbp->sb_inoalignmt != align) {
352 				xfs_warn(mp,
353 "Inode block alignment (%u) must match chunk size (%u) for sparse inodes.",
354 					 sbp->sb_inoalignmt, align);
355 				return -EINVAL;
356 			}
357 		}
358 	} else if (sbp->sb_qflags & (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD |
359 				XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD)) {
360 			xfs_notice(mp,
361 "Superblock earlier than Version 5 has XFS_{P|G}QUOTA_{ENFD|CHKD} bits.");
362 			return -EFSCORRUPTED;
363 	}
364 
365 	if (unlikely(
366 	    sbp->sb_logstart == 0 && mp->m_logdev_targp == mp->m_ddev_targp)) {
367 		xfs_warn(mp,
368 		"filesystem is marked as having an external log; "
369 		"specify logdev on the mount command line.");
370 		return -EINVAL;
371 	}
372 
373 	if (unlikely(
374 	    sbp->sb_logstart != 0 && mp->m_logdev_targp != mp->m_ddev_targp)) {
375 		xfs_warn(mp,
376 		"filesystem is marked as having an internal log; "
377 		"do not specify logdev on the mount command line.");
378 		return -EINVAL;
379 	}
380 
381 	/* Compute agcount for this number of dblocks and agblocks */
382 	if (sbp->sb_agblocks) {
383 		agcount = div_u64_rem(sbp->sb_dblocks, sbp->sb_agblocks, &rem);
384 		if (rem)
385 			agcount++;
386 	}
387 
388 	/*
389 	 * More sanity checking.  Most of these were stolen directly from
390 	 * xfs_repair.
391 	 */
392 	if (unlikely(
393 	    sbp->sb_agcount <= 0					||
394 	    sbp->sb_sectsize < XFS_MIN_SECTORSIZE			||
395 	    sbp->sb_sectsize > XFS_MAX_SECTORSIZE			||
396 	    sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG			||
397 	    sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG			||
398 	    sbp->sb_sectsize != (1 << sbp->sb_sectlog)			||
399 	    sbp->sb_blocksize < XFS_MIN_BLOCKSIZE			||
400 	    sbp->sb_blocksize > XFS_MAX_BLOCKSIZE			||
401 	    sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG			||
402 	    sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG			||
403 	    sbp->sb_blocksize != (1 << sbp->sb_blocklog)		||
404 	    sbp->sb_dirblklog + sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG ||
405 	    sbp->sb_inodesize < XFS_DINODE_MIN_SIZE			||
406 	    sbp->sb_inodesize > XFS_DINODE_MAX_SIZE			||
407 	    sbp->sb_inodelog < XFS_DINODE_MIN_LOG			||
408 	    sbp->sb_inodelog > XFS_DINODE_MAX_LOG			||
409 	    sbp->sb_inodesize != (1 << sbp->sb_inodelog)		||
410 	    sbp->sb_inopblock != howmany(sbp->sb_blocksize,sbp->sb_inodesize) ||
411 	    XFS_FSB_TO_B(mp, sbp->sb_agblocks) < XFS_MIN_AG_BYTES	||
412 	    XFS_FSB_TO_B(mp, sbp->sb_agblocks) > XFS_MAX_AG_BYTES	||
413 	    sbp->sb_agblklog != xfs_highbit32(sbp->sb_agblocks - 1) + 1	||
414 	    agcount == 0 || agcount != sbp->sb_agcount			||
415 	    (sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog)	||
416 	    (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE)	||
417 	    (sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE)	||
418 	    (sbp->sb_imax_pct > 100 /* zero sb_imax_pct is valid */)	||
419 	    sbp->sb_dblocks == 0					||
420 	    sbp->sb_dblocks > XFS_MAX_DBLOCKS(sbp)			||
421 	    sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp)			||
422 	    sbp->sb_shared_vn != 0)) {
423 		xfs_notice(mp, "SB sanity check failed");
424 		return -EFSCORRUPTED;
425 	}
426 
427 	/*
428 	 * Logs that are too large are not supported at all. Reject them
429 	 * outright. Logs that are too small are tolerated on v4 filesystems,
430 	 * but we can only check that when mounting the log. Hence we skip
431 	 * those checks here.
432 	 */
433 	if (sbp->sb_logblocks > XFS_MAX_LOG_BLOCKS) {
434 		xfs_notice(mp,
435 		"Log size 0x%x blocks too large, maximum size is 0x%llx blocks",
436 			 sbp->sb_logblocks, XFS_MAX_LOG_BLOCKS);
437 		return -EFSCORRUPTED;
438 	}
439 
440 	if (XFS_FSB_TO_B(mp, sbp->sb_logblocks) > XFS_MAX_LOG_BYTES) {
441 		xfs_warn(mp,
442 		"log size 0x%llx bytes too large, maximum size is 0x%llx bytes",
443 			 XFS_FSB_TO_B(mp, sbp->sb_logblocks),
444 			 XFS_MAX_LOG_BYTES);
445 		return -EFSCORRUPTED;
446 	}
447 
448 	/*
449 	 * Do not allow filesystems with corrupted log sector or stripe units to
450 	 * be mounted. We cannot safely size the iclogs or write to the log if
451 	 * the log stripe unit is not valid.
452 	 */
453 	if (sbp->sb_versionnum & XFS_SB_VERSION_SECTORBIT) {
454 		if (sbp->sb_logsectsize != (1U << sbp->sb_logsectlog)) {
455 			xfs_notice(mp,
456 			"log sector size in bytes/log2 (0x%x/0x%x) must match",
457 				sbp->sb_logsectsize, 1U << sbp->sb_logsectlog);
458 			return -EFSCORRUPTED;
459 		}
460 	} else if (sbp->sb_logsectsize || sbp->sb_logsectlog) {
461 		xfs_notice(mp,
462 		"log sector size in bytes/log2 (0x%x/0x%x) are not zero",
463 			sbp->sb_logsectsize, sbp->sb_logsectlog);
464 		return -EFSCORRUPTED;
465 	}
466 
467 	if (sbp->sb_logsunit > 1) {
468 		if (sbp->sb_logsunit % sbp->sb_blocksize) {
469 			xfs_notice(mp,
470 		"log stripe unit 0x%x bytes must be a multiple of block size",
471 				sbp->sb_logsunit);
472 			return -EFSCORRUPTED;
473 		}
474 		if (sbp->sb_logsunit > XLOG_MAX_RECORD_BSIZE) {
475 			xfs_notice(mp,
476 		"log stripe unit 0x%x bytes over maximum size (0x%x bytes)",
477 				sbp->sb_logsunit, XLOG_MAX_RECORD_BSIZE);
478 			return -EFSCORRUPTED;
479 		}
480 	}
481 
482 	/* Validate the realtime geometry; stolen from xfs_repair */
483 	if (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE ||
484 	    sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE) {
485 		xfs_notice(mp,
486 			"realtime extent sanity check failed");
487 		return -EFSCORRUPTED;
488 	}
489 
490 	if (sbp->sb_rblocks == 0) {
491 		if (sbp->sb_rextents != 0 || sbp->sb_rbmblocks != 0 ||
492 		    sbp->sb_rextslog != 0 || sbp->sb_frextents != 0) {
493 			xfs_notice(mp,
494 				"realtime zeroed geometry check failed");
495 			return -EFSCORRUPTED;
496 		}
497 	} else {
498 		uint64_t	rexts;
499 		uint64_t	rbmblocks;
500 
501 		rexts = div_u64(sbp->sb_rblocks, sbp->sb_rextsize);
502 		rbmblocks = howmany_64(sbp->sb_rextents,
503 				       NBBY * sbp->sb_blocksize);
504 
505 		if (!xfs_validate_rtextents(rexts) ||
506 		    sbp->sb_rextents != rexts ||
507 		    sbp->sb_rextslog != xfs_compute_rextslog(rexts) ||
508 		    sbp->sb_rbmblocks != rbmblocks) {
509 			xfs_notice(mp,
510 				"realtime geometry sanity check failed");
511 			return -EFSCORRUPTED;
512 		}
513 	}
514 
515 	/*
516 	 * Either (sb_unit and !hasdalign) or (!sb_unit and hasdalign)
517 	 * would imply the image is corrupted.
518 	 */
519 	has_dalign = sbp->sb_versionnum & XFS_SB_VERSION_DALIGNBIT;
520 	if (!!sbp->sb_unit ^ has_dalign) {
521 		xfs_notice(mp, "SB stripe alignment sanity check failed");
522 		return -EFSCORRUPTED;
523 	}
524 
525 	if (!xfs_validate_stripe_geometry(mp, XFS_FSB_TO_B(mp, sbp->sb_unit),
526 			XFS_FSB_TO_B(mp, sbp->sb_width), 0,
527 			xfs_buf_daddr(bp) == XFS_SB_DADDR, false))
528 		return -EFSCORRUPTED;
529 
530 	/*
531 	 * Currently only very few inode sizes are supported.
532 	 */
533 	switch (sbp->sb_inodesize) {
534 	case 256:
535 	case 512:
536 	case 1024:
537 	case 2048:
538 		break;
539 	default:
540 		xfs_warn(mp, "inode size of %d bytes not supported",
541 				sbp->sb_inodesize);
542 		return -ENOSYS;
543 	}
544 
545 	return 0;
546 }
547 
548 void
549 xfs_sb_quota_from_disk(struct xfs_sb *sbp)
550 {
551 	/*
552 	 * older mkfs doesn't initialize quota inodes to NULLFSINO. This
553 	 * leads to in-core values having two different values for a quota
554 	 * inode to be invalid: 0 and NULLFSINO. Change it to a single value
555 	 * NULLFSINO.
556 	 *
557 	 * Note that this change affect only the in-core values. These
558 	 * values are not written back to disk unless any quota information
559 	 * is written to the disk. Even in that case, sb_pquotino field is
560 	 * not written to disk unless the superblock supports pquotino.
561 	 */
562 	if (sbp->sb_uquotino == 0)
563 		sbp->sb_uquotino = NULLFSINO;
564 	if (sbp->sb_gquotino == 0)
565 		sbp->sb_gquotino = NULLFSINO;
566 	if (sbp->sb_pquotino == 0)
567 		sbp->sb_pquotino = NULLFSINO;
568 
569 	/*
570 	 * We need to do these manipilations only if we are working
571 	 * with an older version of on-disk superblock.
572 	 */
573 	if (xfs_sb_is_v5(sbp))
574 		return;
575 
576 	if (sbp->sb_qflags & XFS_OQUOTA_ENFD)
577 		sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ?
578 					XFS_PQUOTA_ENFD : XFS_GQUOTA_ENFD;
579 	if (sbp->sb_qflags & XFS_OQUOTA_CHKD)
580 		sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ?
581 					XFS_PQUOTA_CHKD : XFS_GQUOTA_CHKD;
582 	sbp->sb_qflags &= ~(XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD);
583 
584 	if (sbp->sb_qflags & XFS_PQUOTA_ACCT &&
585 	    sbp->sb_gquotino != NULLFSINO)  {
586 		/*
587 		 * In older version of superblock, on-disk superblock only
588 		 * has sb_gquotino, and in-core superblock has both sb_gquotino
589 		 * and sb_pquotino. But, only one of them is supported at any
590 		 * point of time. So, if PQUOTA is set in disk superblock,
591 		 * copy over sb_gquotino to sb_pquotino.  The NULLFSINO test
592 		 * above is to make sure we don't do this twice and wipe them
593 		 * both out!
594 		 */
595 		sbp->sb_pquotino = sbp->sb_gquotino;
596 		sbp->sb_gquotino = NULLFSINO;
597 	}
598 }
599 
600 static void
601 __xfs_sb_from_disk(
602 	struct xfs_sb	*to,
603 	struct xfs_dsb	*from,
604 	bool		convert_xquota)
605 {
606 	to->sb_magicnum = be32_to_cpu(from->sb_magicnum);
607 	to->sb_blocksize = be32_to_cpu(from->sb_blocksize);
608 	to->sb_dblocks = be64_to_cpu(from->sb_dblocks);
609 	to->sb_rblocks = be64_to_cpu(from->sb_rblocks);
610 	to->sb_rextents = be64_to_cpu(from->sb_rextents);
611 	memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid));
612 	to->sb_logstart = be64_to_cpu(from->sb_logstart);
613 	to->sb_rootino = be64_to_cpu(from->sb_rootino);
614 	to->sb_rbmino = be64_to_cpu(from->sb_rbmino);
615 	to->sb_rsumino = be64_to_cpu(from->sb_rsumino);
616 	to->sb_rextsize = be32_to_cpu(from->sb_rextsize);
617 	to->sb_agblocks = be32_to_cpu(from->sb_agblocks);
618 	to->sb_agcount = be32_to_cpu(from->sb_agcount);
619 	to->sb_rbmblocks = be32_to_cpu(from->sb_rbmblocks);
620 	to->sb_logblocks = be32_to_cpu(from->sb_logblocks);
621 	to->sb_versionnum = be16_to_cpu(from->sb_versionnum);
622 	to->sb_sectsize = be16_to_cpu(from->sb_sectsize);
623 	to->sb_inodesize = be16_to_cpu(from->sb_inodesize);
624 	to->sb_inopblock = be16_to_cpu(from->sb_inopblock);
625 	memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname));
626 	to->sb_blocklog = from->sb_blocklog;
627 	to->sb_sectlog = from->sb_sectlog;
628 	to->sb_inodelog = from->sb_inodelog;
629 	to->sb_inopblog = from->sb_inopblog;
630 	to->sb_agblklog = from->sb_agblklog;
631 	to->sb_rextslog = from->sb_rextslog;
632 	to->sb_inprogress = from->sb_inprogress;
633 	to->sb_imax_pct = from->sb_imax_pct;
634 	to->sb_icount = be64_to_cpu(from->sb_icount);
635 	to->sb_ifree = be64_to_cpu(from->sb_ifree);
636 	to->sb_fdblocks = be64_to_cpu(from->sb_fdblocks);
637 	to->sb_frextents = be64_to_cpu(from->sb_frextents);
638 	to->sb_uquotino = be64_to_cpu(from->sb_uquotino);
639 	to->sb_gquotino = be64_to_cpu(from->sb_gquotino);
640 	to->sb_qflags = be16_to_cpu(from->sb_qflags);
641 	to->sb_flags = from->sb_flags;
642 	to->sb_shared_vn = from->sb_shared_vn;
643 	to->sb_inoalignmt = be32_to_cpu(from->sb_inoalignmt);
644 	to->sb_unit = be32_to_cpu(from->sb_unit);
645 	to->sb_width = be32_to_cpu(from->sb_width);
646 	to->sb_dirblklog = from->sb_dirblklog;
647 	to->sb_logsectlog = from->sb_logsectlog;
648 	to->sb_logsectsize = be16_to_cpu(from->sb_logsectsize);
649 	to->sb_logsunit = be32_to_cpu(from->sb_logsunit);
650 	to->sb_features2 = be32_to_cpu(from->sb_features2);
651 	to->sb_bad_features2 = be32_to_cpu(from->sb_bad_features2);
652 	to->sb_features_compat = be32_to_cpu(from->sb_features_compat);
653 	to->sb_features_ro_compat = be32_to_cpu(from->sb_features_ro_compat);
654 	to->sb_features_incompat = be32_to_cpu(from->sb_features_incompat);
655 	to->sb_features_log_incompat =
656 				be32_to_cpu(from->sb_features_log_incompat);
657 	/* crc is only used on disk, not in memory; just init to 0 here. */
658 	to->sb_crc = 0;
659 	to->sb_spino_align = be32_to_cpu(from->sb_spino_align);
660 	to->sb_pquotino = be64_to_cpu(from->sb_pquotino);
661 	to->sb_lsn = be64_to_cpu(from->sb_lsn);
662 	/*
663 	 * sb_meta_uuid is only on disk if it differs from sb_uuid and the
664 	 * feature flag is set; if not set we keep it only in memory.
665 	 */
666 	if (xfs_sb_is_v5(to) &&
667 	    (to->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_META_UUID))
668 		uuid_copy(&to->sb_meta_uuid, &from->sb_meta_uuid);
669 	else
670 		uuid_copy(&to->sb_meta_uuid, &from->sb_uuid);
671 	/* Convert on-disk flags to in-memory flags? */
672 	if (convert_xquota)
673 		xfs_sb_quota_from_disk(to);
674 }
675 
676 void
677 xfs_sb_from_disk(
678 	struct xfs_sb	*to,
679 	struct xfs_dsb	*from)
680 {
681 	__xfs_sb_from_disk(to, from, true);
682 }
683 
684 static void
685 xfs_sb_quota_to_disk(
686 	struct xfs_dsb	*to,
687 	struct xfs_sb	*from)
688 {
689 	uint16_t	qflags = from->sb_qflags;
690 
691 	to->sb_uquotino = cpu_to_be64(from->sb_uquotino);
692 
693 	/*
694 	 * The in-memory superblock quota state matches the v5 on-disk format so
695 	 * just write them out and return
696 	 */
697 	if (xfs_sb_is_v5(from)) {
698 		to->sb_qflags = cpu_to_be16(from->sb_qflags);
699 		to->sb_gquotino = cpu_to_be64(from->sb_gquotino);
700 		to->sb_pquotino = cpu_to_be64(from->sb_pquotino);
701 		return;
702 	}
703 
704 	/*
705 	 * For older superblocks (v4), the in-core version of sb_qflags do not
706 	 * have XFS_OQUOTA_* flags, whereas the on-disk version does.  So,
707 	 * convert incore XFS_{PG}QUOTA_* flags to on-disk XFS_OQUOTA_* flags.
708 	 */
709 	qflags &= ~(XFS_PQUOTA_ENFD | XFS_PQUOTA_CHKD |
710 			XFS_GQUOTA_ENFD | XFS_GQUOTA_CHKD);
711 
712 	if (from->sb_qflags &
713 			(XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD))
714 		qflags |= XFS_OQUOTA_ENFD;
715 	if (from->sb_qflags &
716 			(XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD))
717 		qflags |= XFS_OQUOTA_CHKD;
718 	to->sb_qflags = cpu_to_be16(qflags);
719 
720 	/*
721 	 * GQUOTINO and PQUOTINO cannot be used together in versions
722 	 * of superblock that do not have pquotino. from->sb_flags
723 	 * tells us which quota is active and should be copied to
724 	 * disk. If neither are active, we should NULL the inode.
725 	 *
726 	 * In all cases, the separate pquotino must remain 0 because it
727 	 * is beyond the "end" of the valid non-pquotino superblock.
728 	 */
729 	if (from->sb_qflags & XFS_GQUOTA_ACCT)
730 		to->sb_gquotino = cpu_to_be64(from->sb_gquotino);
731 	else if (from->sb_qflags & XFS_PQUOTA_ACCT)
732 		to->sb_gquotino = cpu_to_be64(from->sb_pquotino);
733 	else {
734 		/*
735 		 * We can't rely on just the fields being logged to tell us
736 		 * that it is safe to write NULLFSINO - we should only do that
737 		 * if quotas are not actually enabled. Hence only write
738 		 * NULLFSINO if both in-core quota inodes are NULL.
739 		 */
740 		if (from->sb_gquotino == NULLFSINO &&
741 		    from->sb_pquotino == NULLFSINO)
742 			to->sb_gquotino = cpu_to_be64(NULLFSINO);
743 	}
744 
745 	to->sb_pquotino = 0;
746 }
747 
748 void
749 xfs_sb_to_disk(
750 	struct xfs_dsb	*to,
751 	struct xfs_sb	*from)
752 {
753 	xfs_sb_quota_to_disk(to, from);
754 
755 	to->sb_magicnum = cpu_to_be32(from->sb_magicnum);
756 	to->sb_blocksize = cpu_to_be32(from->sb_blocksize);
757 	to->sb_dblocks = cpu_to_be64(from->sb_dblocks);
758 	to->sb_rblocks = cpu_to_be64(from->sb_rblocks);
759 	to->sb_rextents = cpu_to_be64(from->sb_rextents);
760 	memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid));
761 	to->sb_logstart = cpu_to_be64(from->sb_logstart);
762 	to->sb_rootino = cpu_to_be64(from->sb_rootino);
763 	to->sb_rbmino = cpu_to_be64(from->sb_rbmino);
764 	to->sb_rsumino = cpu_to_be64(from->sb_rsumino);
765 	to->sb_rextsize = cpu_to_be32(from->sb_rextsize);
766 	to->sb_agblocks = cpu_to_be32(from->sb_agblocks);
767 	to->sb_agcount = cpu_to_be32(from->sb_agcount);
768 	to->sb_rbmblocks = cpu_to_be32(from->sb_rbmblocks);
769 	to->sb_logblocks = cpu_to_be32(from->sb_logblocks);
770 	to->sb_versionnum = cpu_to_be16(from->sb_versionnum);
771 	to->sb_sectsize = cpu_to_be16(from->sb_sectsize);
772 	to->sb_inodesize = cpu_to_be16(from->sb_inodesize);
773 	to->sb_inopblock = cpu_to_be16(from->sb_inopblock);
774 	memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname));
775 	to->sb_blocklog = from->sb_blocklog;
776 	to->sb_sectlog = from->sb_sectlog;
777 	to->sb_inodelog = from->sb_inodelog;
778 	to->sb_inopblog = from->sb_inopblog;
779 	to->sb_agblklog = from->sb_agblklog;
780 	to->sb_rextslog = from->sb_rextslog;
781 	to->sb_inprogress = from->sb_inprogress;
782 	to->sb_imax_pct = from->sb_imax_pct;
783 	to->sb_icount = cpu_to_be64(from->sb_icount);
784 	to->sb_ifree = cpu_to_be64(from->sb_ifree);
785 	to->sb_fdblocks = cpu_to_be64(from->sb_fdblocks);
786 	to->sb_frextents = cpu_to_be64(from->sb_frextents);
787 
788 	to->sb_flags = from->sb_flags;
789 	to->sb_shared_vn = from->sb_shared_vn;
790 	to->sb_inoalignmt = cpu_to_be32(from->sb_inoalignmt);
791 	to->sb_unit = cpu_to_be32(from->sb_unit);
792 	to->sb_width = cpu_to_be32(from->sb_width);
793 	to->sb_dirblklog = from->sb_dirblklog;
794 	to->sb_logsectlog = from->sb_logsectlog;
795 	to->sb_logsectsize = cpu_to_be16(from->sb_logsectsize);
796 	to->sb_logsunit = cpu_to_be32(from->sb_logsunit);
797 
798 	/*
799 	 * We need to ensure that bad_features2 always matches features2.
800 	 * Hence we enforce that here rather than having to remember to do it
801 	 * everywhere else that updates features2.
802 	 */
803 	from->sb_bad_features2 = from->sb_features2;
804 	to->sb_features2 = cpu_to_be32(from->sb_features2);
805 	to->sb_bad_features2 = cpu_to_be32(from->sb_bad_features2);
806 
807 	if (!xfs_sb_is_v5(from))
808 		return;
809 
810 	to->sb_features_compat = cpu_to_be32(from->sb_features_compat);
811 	to->sb_features_ro_compat =
812 			cpu_to_be32(from->sb_features_ro_compat);
813 	to->sb_features_incompat =
814 			cpu_to_be32(from->sb_features_incompat);
815 	to->sb_features_log_incompat =
816 			cpu_to_be32(from->sb_features_log_incompat);
817 	to->sb_spino_align = cpu_to_be32(from->sb_spino_align);
818 	to->sb_lsn = cpu_to_be64(from->sb_lsn);
819 	if (from->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_META_UUID)
820 		uuid_copy(&to->sb_meta_uuid, &from->sb_meta_uuid);
821 }
822 
823 /*
824  * If the superblock has the CRC feature bit set or the CRC field is non-null,
825  * check that the CRC is valid.  We check the CRC field is non-null because a
826  * single bit error could clear the feature bit and unused parts of the
827  * superblock are supposed to be zero. Hence a non-null crc field indicates that
828  * we've potentially lost a feature bit and we should check it anyway.
829  *
830  * However, past bugs (i.e. in growfs) left non-zeroed regions beyond the
831  * last field in V4 secondary superblocks.  So for secondary superblocks,
832  * we are more forgiving, and ignore CRC failures if the primary doesn't
833  * indicate that the fs version is V5.
834  */
835 static void
836 xfs_sb_read_verify(
837 	struct xfs_buf		*bp)
838 {
839 	struct xfs_sb		sb;
840 	struct xfs_mount	*mp = bp->b_mount;
841 	struct xfs_dsb		*dsb = bp->b_addr;
842 	int			error;
843 
844 	/*
845 	 * open code the version check to avoid needing to convert the entire
846 	 * superblock from disk order just to check the version number
847 	 */
848 	if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC) &&
849 	    (((be16_to_cpu(dsb->sb_versionnum) & XFS_SB_VERSION_NUMBITS) ==
850 						XFS_SB_VERSION_5) ||
851 	     dsb->sb_crc != 0)) {
852 
853 		if (!xfs_buf_verify_cksum(bp, XFS_SB_CRC_OFF)) {
854 			/* Only fail bad secondaries on a known V5 filesystem */
855 			if (xfs_buf_daddr(bp) == XFS_SB_DADDR ||
856 			    xfs_has_crc(mp)) {
857 				error = -EFSBADCRC;
858 				goto out_error;
859 			}
860 		}
861 	}
862 
863 	/*
864 	 * Check all the superblock fields.  Don't byteswap the xquota flags
865 	 * because _verify_common checks the on-disk values.
866 	 */
867 	__xfs_sb_from_disk(&sb, dsb, false);
868 	error = xfs_validate_sb_common(mp, bp, &sb);
869 	if (error)
870 		goto out_error;
871 	error = xfs_validate_sb_read(mp, &sb);
872 
873 out_error:
874 	if (error == -EFSCORRUPTED || error == -EFSBADCRC)
875 		xfs_verifier_error(bp, error, __this_address);
876 	else if (error)
877 		xfs_buf_ioerror(bp, error);
878 }
879 
880 /*
881  * We may be probed for a filesystem match, so we may not want to emit
882  * messages when the superblock buffer is not actually an XFS superblock.
883  * If we find an XFS superblock, then run a normal, noisy mount because we are
884  * really going to mount it and want to know about errors.
885  */
886 static void
887 xfs_sb_quiet_read_verify(
888 	struct xfs_buf	*bp)
889 {
890 	struct xfs_dsb	*dsb = bp->b_addr;
891 
892 	if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC)) {
893 		/* XFS filesystem, verify noisily! */
894 		xfs_sb_read_verify(bp);
895 		return;
896 	}
897 	/* quietly fail */
898 	xfs_buf_ioerror(bp, -EWRONGFS);
899 }
900 
901 static void
902 xfs_sb_write_verify(
903 	struct xfs_buf		*bp)
904 {
905 	struct xfs_sb		sb;
906 	struct xfs_mount	*mp = bp->b_mount;
907 	struct xfs_buf_log_item	*bip = bp->b_log_item;
908 	struct xfs_dsb		*dsb = bp->b_addr;
909 	int			error;
910 
911 	/*
912 	 * Check all the superblock fields.  Don't byteswap the xquota flags
913 	 * because _verify_common checks the on-disk values.
914 	 */
915 	__xfs_sb_from_disk(&sb, dsb, false);
916 	error = xfs_validate_sb_common(mp, bp, &sb);
917 	if (error)
918 		goto out_error;
919 	error = xfs_validate_sb_write(mp, bp, &sb);
920 	if (error)
921 		goto out_error;
922 
923 	if (!xfs_sb_is_v5(&sb))
924 		return;
925 
926 	if (bip)
927 		dsb->sb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
928 
929 	xfs_buf_update_cksum(bp, XFS_SB_CRC_OFF);
930 	return;
931 
932 out_error:
933 	xfs_verifier_error(bp, error, __this_address);
934 }
935 
936 const struct xfs_buf_ops xfs_sb_buf_ops = {
937 	.name = "xfs_sb",
938 	.magic = { cpu_to_be32(XFS_SB_MAGIC), cpu_to_be32(XFS_SB_MAGIC) },
939 	.verify_read = xfs_sb_read_verify,
940 	.verify_write = xfs_sb_write_verify,
941 };
942 
943 const struct xfs_buf_ops xfs_sb_quiet_buf_ops = {
944 	.name = "xfs_sb_quiet",
945 	.magic = { cpu_to_be32(XFS_SB_MAGIC), cpu_to_be32(XFS_SB_MAGIC) },
946 	.verify_read = xfs_sb_quiet_read_verify,
947 	.verify_write = xfs_sb_write_verify,
948 };
949 
950 /*
951  * xfs_mount_common
952  *
953  * Mount initialization code establishing various mount
954  * fields from the superblock associated with the given
955  * mount structure.
956  *
957  * Inode geometry are calculated in xfs_ialloc_setup_geometry.
958  */
959 void
960 xfs_sb_mount_common(
961 	struct xfs_mount	*mp,
962 	struct xfs_sb		*sbp)
963 {
964 	mp->m_agfrotor = 0;
965 	atomic_set(&mp->m_agirotor, 0);
966 	mp->m_maxagi = mp->m_sb.sb_agcount;
967 	mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG;
968 	mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT;
969 	mp->m_sectbb_log = sbp->sb_sectlog - BBSHIFT;
970 	mp->m_agno_log = xfs_highbit32(sbp->sb_agcount - 1) + 1;
971 	mp->m_blockmask = sbp->sb_blocksize - 1;
972 	mp->m_blockwsize = sbp->sb_blocksize >> XFS_WORDLOG;
973 	mp->m_blockwmask = mp->m_blockwsize - 1;
974 
975 	mp->m_alloc_mxr[0] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 1);
976 	mp->m_alloc_mxr[1] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 0);
977 	mp->m_alloc_mnr[0] = mp->m_alloc_mxr[0] / 2;
978 	mp->m_alloc_mnr[1] = mp->m_alloc_mxr[1] / 2;
979 
980 	mp->m_bmap_dmxr[0] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 1);
981 	mp->m_bmap_dmxr[1] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 0);
982 	mp->m_bmap_dmnr[0] = mp->m_bmap_dmxr[0] / 2;
983 	mp->m_bmap_dmnr[1] = mp->m_bmap_dmxr[1] / 2;
984 
985 	mp->m_rmap_mxr[0] = xfs_rmapbt_maxrecs(sbp->sb_blocksize, 1);
986 	mp->m_rmap_mxr[1] = xfs_rmapbt_maxrecs(sbp->sb_blocksize, 0);
987 	mp->m_rmap_mnr[0] = mp->m_rmap_mxr[0] / 2;
988 	mp->m_rmap_mnr[1] = mp->m_rmap_mxr[1] / 2;
989 
990 	mp->m_refc_mxr[0] = xfs_refcountbt_maxrecs(sbp->sb_blocksize, true);
991 	mp->m_refc_mxr[1] = xfs_refcountbt_maxrecs(sbp->sb_blocksize, false);
992 	mp->m_refc_mnr[0] = mp->m_refc_mxr[0] / 2;
993 	mp->m_refc_mnr[1] = mp->m_refc_mxr[1] / 2;
994 
995 	mp->m_bsize = XFS_FSB_TO_BB(mp, 1);
996 	mp->m_alloc_set_aside = xfs_alloc_set_aside(mp);
997 	mp->m_ag_max_usable = xfs_alloc_ag_max_usable(mp);
998 }
999 
1000 /*
1001  * xfs_log_sb() can be used to copy arbitrary changes to the in-core superblock
1002  * into the superblock buffer to be logged.  It does not provide the higher
1003  * level of locking that is needed to protect the in-core superblock from
1004  * concurrent access.
1005  */
1006 void
1007 xfs_log_sb(
1008 	struct xfs_trans	*tp)
1009 {
1010 	struct xfs_mount	*mp = tp->t_mountp;
1011 	struct xfs_buf		*bp = xfs_trans_getsb(tp);
1012 
1013 	/*
1014 	 * Lazy sb counters don't update the in-core superblock so do that now.
1015 	 * If this is at unmount, the counters will be exactly correct, but at
1016 	 * any other time they will only be ballpark correct because of
1017 	 * reservations that have been taken out percpu counters. If we have an
1018 	 * unclean shutdown, this will be corrected by log recovery rebuilding
1019 	 * the counters from the AGF block counts.
1020 	 *
1021 	 * Do not update sb_frextents here because it is not part of the lazy
1022 	 * sb counters, despite having a percpu counter. It is always kept
1023 	 * consistent with the ondisk rtbitmap by xfs_trans_apply_sb_deltas()
1024 	 * and hence we don't need have to update it here.
1025 	 */
1026 	if (xfs_has_lazysbcount(mp)) {
1027 		mp->m_sb.sb_icount = percpu_counter_sum_positive(&mp->m_icount);
1028 		mp->m_sb.sb_ifree = min_t(uint64_t,
1029 				percpu_counter_sum_positive(&mp->m_ifree),
1030 				mp->m_sb.sb_icount);
1031 		mp->m_sb.sb_fdblocks =
1032 				percpu_counter_sum_positive(&mp->m_fdblocks);
1033 	}
1034 
1035 	xfs_sb_to_disk(bp->b_addr, &mp->m_sb);
1036 	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF);
1037 	xfs_trans_log_buf(tp, bp, 0, sizeof(struct xfs_dsb) - 1);
1038 }
1039 
1040 /*
1041  * xfs_sync_sb
1042  *
1043  * Sync the superblock to disk.
1044  *
1045  * Note that the caller is responsible for checking the frozen state of the
1046  * filesystem. This procedure uses the non-blocking transaction allocator and
1047  * thus will allow modifications to a frozen fs. This is required because this
1048  * code can be called during the process of freezing where use of the high-level
1049  * allocator would deadlock.
1050  */
1051 int
1052 xfs_sync_sb(
1053 	struct xfs_mount	*mp,
1054 	bool			wait)
1055 {
1056 	struct xfs_trans	*tp;
1057 	int			error;
1058 
1059 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_sb, 0, 0,
1060 			XFS_TRANS_NO_WRITECOUNT, &tp);
1061 	if (error)
1062 		return error;
1063 
1064 	xfs_log_sb(tp);
1065 	if (wait)
1066 		xfs_trans_set_sync(tp);
1067 	return xfs_trans_commit(tp);
1068 }
1069 
1070 /*
1071  * Update all the secondary superblocks to match the new state of the primary.
1072  * Because we are completely overwriting all the existing fields in the
1073  * secondary superblock buffers, there is no need to read them in from disk.
1074  * Just get a new buffer, stamp it and write it.
1075  *
1076  * The sb buffers need to be cached here so that we serialise against other
1077  * operations that access the secondary superblocks, but we don't want to keep
1078  * them in memory once it is written so we mark it as a one-shot buffer.
1079  */
1080 int
1081 xfs_update_secondary_sbs(
1082 	struct xfs_mount	*mp)
1083 {
1084 	struct xfs_perag	*pag;
1085 	xfs_agnumber_t		agno = 1;
1086 	int			saved_error = 0;
1087 	int			error = 0;
1088 	LIST_HEAD		(buffer_list);
1089 
1090 	/* update secondary superblocks. */
1091 	for_each_perag_from(mp, agno, pag) {
1092 		struct xfs_buf		*bp;
1093 
1094 		error = xfs_buf_get(mp->m_ddev_targp,
1095 				 XFS_AG_DADDR(mp, pag->pag_agno, XFS_SB_DADDR),
1096 				 XFS_FSS_TO_BB(mp, 1), &bp);
1097 		/*
1098 		 * If we get an error reading or writing alternate superblocks,
1099 		 * continue.  xfs_repair chooses the "best" superblock based
1100 		 * on most matches; if we break early, we'll leave more
1101 		 * superblocks un-updated than updated, and xfs_repair may
1102 		 * pick them over the properly-updated primary.
1103 		 */
1104 		if (error) {
1105 			xfs_warn(mp,
1106 		"error allocating secondary superblock for ag %d",
1107 				pag->pag_agno);
1108 			if (!saved_error)
1109 				saved_error = error;
1110 			continue;
1111 		}
1112 
1113 		bp->b_ops = &xfs_sb_buf_ops;
1114 		xfs_buf_oneshot(bp);
1115 		xfs_buf_zero(bp, 0, BBTOB(bp->b_length));
1116 		xfs_sb_to_disk(bp->b_addr, &mp->m_sb);
1117 		xfs_buf_delwri_queue(bp, &buffer_list);
1118 		xfs_buf_relse(bp);
1119 
1120 		/* don't hold too many buffers at once */
1121 		if (agno % 16)
1122 			continue;
1123 
1124 		error = xfs_buf_delwri_submit(&buffer_list);
1125 		if (error) {
1126 			xfs_warn(mp,
1127 		"write error %d updating a secondary superblock near ag %d",
1128 				error, pag->pag_agno);
1129 			if (!saved_error)
1130 				saved_error = error;
1131 			continue;
1132 		}
1133 	}
1134 	error = xfs_buf_delwri_submit(&buffer_list);
1135 	if (error) {
1136 		xfs_warn(mp,
1137 		"write error %d updating a secondary superblock near ag %d",
1138 			error, agno);
1139 	}
1140 
1141 	return saved_error ? saved_error : error;
1142 }
1143 
1144 /*
1145  * Same behavior as xfs_sync_sb, except that it is always synchronous and it
1146  * also writes the superblock buffer to disk sector 0 immediately.
1147  */
1148 int
1149 xfs_sync_sb_buf(
1150 	struct xfs_mount	*mp)
1151 {
1152 	struct xfs_trans	*tp;
1153 	struct xfs_buf		*bp;
1154 	int			error;
1155 
1156 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_sb, 0, 0, 0, &tp);
1157 	if (error)
1158 		return error;
1159 
1160 	bp = xfs_trans_getsb(tp);
1161 	xfs_log_sb(tp);
1162 	xfs_trans_bhold(tp, bp);
1163 	xfs_trans_set_sync(tp);
1164 	error = xfs_trans_commit(tp);
1165 	if (error)
1166 		goto out;
1167 	/*
1168 	 * write out the sb buffer to get the changes to disk
1169 	 */
1170 	error = xfs_bwrite(bp);
1171 out:
1172 	xfs_buf_relse(bp);
1173 	return error;
1174 }
1175 
1176 void
1177 xfs_fs_geometry(
1178 	struct xfs_mount	*mp,
1179 	struct xfs_fsop_geom	*geo,
1180 	int			struct_version)
1181 {
1182 	struct xfs_sb		*sbp = &mp->m_sb;
1183 
1184 	memset(geo, 0, sizeof(struct xfs_fsop_geom));
1185 
1186 	geo->blocksize = sbp->sb_blocksize;
1187 	geo->rtextsize = sbp->sb_rextsize;
1188 	geo->agblocks = sbp->sb_agblocks;
1189 	geo->agcount = sbp->sb_agcount;
1190 	geo->logblocks = sbp->sb_logblocks;
1191 	geo->sectsize = sbp->sb_sectsize;
1192 	geo->inodesize = sbp->sb_inodesize;
1193 	geo->imaxpct = sbp->sb_imax_pct;
1194 	geo->datablocks = sbp->sb_dblocks;
1195 	geo->rtblocks = sbp->sb_rblocks;
1196 	geo->rtextents = sbp->sb_rextents;
1197 	geo->logstart = sbp->sb_logstart;
1198 	BUILD_BUG_ON(sizeof(geo->uuid) != sizeof(sbp->sb_uuid));
1199 	memcpy(geo->uuid, &sbp->sb_uuid, sizeof(sbp->sb_uuid));
1200 
1201 	if (struct_version < 2)
1202 		return;
1203 
1204 	geo->sunit = sbp->sb_unit;
1205 	geo->swidth = sbp->sb_width;
1206 
1207 	if (struct_version < 3)
1208 		return;
1209 
1210 	geo->version = XFS_FSOP_GEOM_VERSION;
1211 	geo->flags = XFS_FSOP_GEOM_FLAGS_NLINK |
1212 		     XFS_FSOP_GEOM_FLAGS_DIRV2 |
1213 		     XFS_FSOP_GEOM_FLAGS_EXTFLG;
1214 	if (xfs_has_attr(mp))
1215 		geo->flags |= XFS_FSOP_GEOM_FLAGS_ATTR;
1216 	if (xfs_has_quota(mp))
1217 		geo->flags |= XFS_FSOP_GEOM_FLAGS_QUOTA;
1218 	if (xfs_has_align(mp))
1219 		geo->flags |= XFS_FSOP_GEOM_FLAGS_IALIGN;
1220 	if (xfs_has_dalign(mp))
1221 		geo->flags |= XFS_FSOP_GEOM_FLAGS_DALIGN;
1222 	if (xfs_has_asciici(mp))
1223 		geo->flags |= XFS_FSOP_GEOM_FLAGS_DIRV2CI;
1224 	if (xfs_has_lazysbcount(mp))
1225 		geo->flags |= XFS_FSOP_GEOM_FLAGS_LAZYSB;
1226 	if (xfs_has_attr2(mp))
1227 		geo->flags |= XFS_FSOP_GEOM_FLAGS_ATTR2;
1228 	if (xfs_has_projid32(mp))
1229 		geo->flags |= XFS_FSOP_GEOM_FLAGS_PROJID32;
1230 	if (xfs_has_crc(mp))
1231 		geo->flags |= XFS_FSOP_GEOM_FLAGS_V5SB;
1232 	if (xfs_has_ftype(mp))
1233 		geo->flags |= XFS_FSOP_GEOM_FLAGS_FTYPE;
1234 	if (xfs_has_finobt(mp))
1235 		geo->flags |= XFS_FSOP_GEOM_FLAGS_FINOBT;
1236 	if (xfs_has_sparseinodes(mp))
1237 		geo->flags |= XFS_FSOP_GEOM_FLAGS_SPINODES;
1238 	if (xfs_has_rmapbt(mp))
1239 		geo->flags |= XFS_FSOP_GEOM_FLAGS_RMAPBT;
1240 	if (xfs_has_reflink(mp))
1241 		geo->flags |= XFS_FSOP_GEOM_FLAGS_REFLINK;
1242 	if (xfs_has_bigtime(mp))
1243 		geo->flags |= XFS_FSOP_GEOM_FLAGS_BIGTIME;
1244 	if (xfs_has_inobtcounts(mp))
1245 		geo->flags |= XFS_FSOP_GEOM_FLAGS_INOBTCNT;
1246 	if (xfs_has_sector(mp)) {
1247 		geo->flags |= XFS_FSOP_GEOM_FLAGS_SECTOR;
1248 		geo->logsectsize = sbp->sb_logsectsize;
1249 	} else {
1250 		geo->logsectsize = BBSIZE;
1251 	}
1252 	if (xfs_has_large_extent_counts(mp))
1253 		geo->flags |= XFS_FSOP_GEOM_FLAGS_NREXT64;
1254 	geo->rtsectsize = sbp->sb_blocksize;
1255 	geo->dirblocksize = xfs_dir2_dirblock_bytes(sbp);
1256 
1257 	if (struct_version < 4)
1258 		return;
1259 
1260 	if (xfs_has_logv2(mp))
1261 		geo->flags |= XFS_FSOP_GEOM_FLAGS_LOGV2;
1262 
1263 	geo->logsunit = sbp->sb_logsunit;
1264 
1265 	if (struct_version < 5)
1266 		return;
1267 
1268 	geo->version = XFS_FSOP_GEOM_VERSION_V5;
1269 }
1270 
1271 /* Read a secondary superblock. */
1272 int
1273 xfs_sb_read_secondary(
1274 	struct xfs_mount	*mp,
1275 	struct xfs_trans	*tp,
1276 	xfs_agnumber_t		agno,
1277 	struct xfs_buf		**bpp)
1278 {
1279 	struct xfs_buf		*bp;
1280 	int			error;
1281 
1282 	ASSERT(agno != 0 && agno != NULLAGNUMBER);
1283 	error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
1284 			XFS_AG_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
1285 			XFS_FSS_TO_BB(mp, 1), 0, &bp, &xfs_sb_buf_ops);
1286 	if (error)
1287 		return error;
1288 	xfs_buf_set_ref(bp, XFS_SSB_REF);
1289 	*bpp = bp;
1290 	return 0;
1291 }
1292 
1293 /* Get an uninitialised secondary superblock buffer. */
1294 int
1295 xfs_sb_get_secondary(
1296 	struct xfs_mount	*mp,
1297 	struct xfs_trans	*tp,
1298 	xfs_agnumber_t		agno,
1299 	struct xfs_buf		**bpp)
1300 {
1301 	struct xfs_buf		*bp;
1302 	int			error;
1303 
1304 	ASSERT(agno != 0 && agno != NULLAGNUMBER);
1305 	error = xfs_trans_get_buf(tp, mp->m_ddev_targp,
1306 			XFS_AG_DADDR(mp, agno, XFS_SB_BLOCK(mp)),
1307 			XFS_FSS_TO_BB(mp, 1), 0, &bp);
1308 	if (error)
1309 		return error;
1310 	bp->b_ops = &xfs_sb_buf_ops;
1311 	xfs_buf_oneshot(bp);
1312 	*bpp = bp;
1313 	return 0;
1314 }
1315 
1316 /*
1317  * sunit, swidth, sectorsize(optional with 0) should be all in bytes, so users
1318  * won't be confused by values in error messages.  This function returns false
1319  * if the stripe geometry is invalid and the caller is unable to repair the
1320  * stripe configuration later in the mount process.
1321  */
1322 bool
1323 xfs_validate_stripe_geometry(
1324 	struct xfs_mount	*mp,
1325 	__s64			sunit,
1326 	__s64			swidth,
1327 	int			sectorsize,
1328 	bool			may_repair,
1329 	bool			silent)
1330 {
1331 	if (swidth > INT_MAX) {
1332 		if (!silent)
1333 			xfs_notice(mp,
1334 "stripe width (%lld) is too large", swidth);
1335 		goto check_override;
1336 	}
1337 
1338 	if (sunit > swidth) {
1339 		if (!silent)
1340 			xfs_notice(mp,
1341 "stripe unit (%lld) is larger than the stripe width (%lld)", sunit, swidth);
1342 		goto check_override;
1343 	}
1344 
1345 	if (sectorsize && (int)sunit % sectorsize) {
1346 		if (!silent)
1347 			xfs_notice(mp,
1348 "stripe unit (%lld) must be a multiple of the sector size (%d)",
1349 				   sunit, sectorsize);
1350 		goto check_override;
1351 	}
1352 
1353 	if (sunit && !swidth) {
1354 		if (!silent)
1355 			xfs_notice(mp,
1356 "invalid stripe unit (%lld) and stripe width of 0", sunit);
1357 		goto check_override;
1358 	}
1359 
1360 	if (!sunit && swidth) {
1361 		if (!silent)
1362 			xfs_notice(mp,
1363 "invalid stripe width (%lld) and stripe unit of 0", swidth);
1364 		goto check_override;
1365 	}
1366 
1367 	if (sunit && (int)swidth % (int)sunit) {
1368 		if (!silent)
1369 			xfs_notice(mp,
1370 "stripe width (%lld) must be a multiple of the stripe unit (%lld)",
1371 				   swidth, sunit);
1372 		goto check_override;
1373 	}
1374 	return true;
1375 
1376 check_override:
1377 	if (!may_repair)
1378 		return false;
1379 	/*
1380 	 * During mount, mp->m_dalign will not be set unless the sunit mount
1381 	 * option was set. If it was set, ignore the bad stripe alignment values
1382 	 * and allow the validation and overwrite later in the mount process to
1383 	 * attempt to overwrite the bad stripe alignment values with the values
1384 	 * supplied by mount options.
1385 	 */
1386 	if (!mp->m_dalign)
1387 		return false;
1388 	if (!silent)
1389 		xfs_notice(mp,
1390 "Will try to correct with specified mount options sunit (%d) and swidth (%d)",
1391 			BBTOB(mp->m_dalign), BBTOB(mp->m_swidth));
1392 	return true;
1393 }
1394 
1395 /*
1396  * Compute the maximum level number of the realtime summary file, as defined by
1397  * mkfs.  The historic use of highbit32 on a 64-bit quantity prohibited correct
1398  * use of rt volumes with more than 2^32 extents.
1399  */
1400 uint8_t
1401 xfs_compute_rextslog(
1402 	xfs_rtbxlen_t		rtextents)
1403 {
1404 	if (!rtextents)
1405 		return 0;
1406 	return xfs_highbit64(rtextents);
1407 }
1408