xref: /freebsd/sys/ufs/ffs/fs.h (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef _UFS_FFS_FS_H_
33 #define	_UFS_FFS_FS_H_
34 
35 #include <sys/mount.h>
36 #include <ufs/ufs/dinode.h>
37 
38 /*
39  * Each disk drive contains some number of filesystems.
40  * A filesystem consists of a number of cylinder groups.
41  * Each cylinder group has inodes and data.
42  *
43  * A filesystem is described by its super-block, which in turn
44  * describes the cylinder groups.  The super-block is critical
45  * data and is replicated in each cylinder group to protect against
46  * catastrophic loss.  This is done at `newfs' time and the critical
47  * super-block data does not change, so the copies need not be
48  * referenced further unless disaster strikes.
49  *
50  * For filesystem fs, the offsets of the various blocks of interest
51  * are given in the super block as:
52  *	[fs->fs_sblkno]		Super-block
53  *	[fs->fs_cblkno]		Cylinder group block
54  *	[fs->fs_iblkno]		Inode blocks
55  *	[fs->fs_dblkno]		Data blocks
56  * The beginning of cylinder group cg in fs, is given by
57  * the ``cgbase(fs, cg)'' macro.
58  *
59  * Depending on the architecture and the media, the superblock may
60  * reside in any one of four places. For tiny media where every block
61  * counts, it is placed at the very front of the partition. Historically,
62  * UFS1 placed it 8K from the front to leave room for the disk label and
63  * a small bootstrap. For UFS2 it got moved to 64K from the front to leave
64  * room for the disk label and a bigger bootstrap, and for really piggy
65  * systems we check at 256K from the front if the first three fail. In
66  * all cases the size of the superblock will be SBLOCKSIZE. All values are
67  * given in byte-offset form, so they do not imply a sector size. The
68  * SBLOCKSEARCH specifies the order in which the locations should be searched.
69  */
70 #define	SBLOCK_FLOPPY	     0
71 #define	SBLOCK_UFS1	  8192
72 #define	SBLOCK_UFS2	 65536
73 #define	SBLOCK_PIGGY	262144
74 #define	SBLOCKSIZE	  8192
75 #define	SBLOCKSEARCH \
76 	{ SBLOCK_UFS2, SBLOCK_UFS1, SBLOCK_FLOPPY, SBLOCK_PIGGY, -1 }
77 /*
78  * Request standard superblock location in ffs_sbget().
79  */
80 #define	UFS_STDSB	-1	/* Search standard places for superblock */
81 
82 /*
83  * UFS_NOMSG indicates that superblock inconsistency error messages
84  *    should not be printed. It is used by programs like fsck that
85  *    want to print their own error message.
86  *
87  * UFS_NOCSUM causes only the superblock itself to be returned, but does
88  *    not read in any auxiliary data structures like the cylinder group
89  *    summary information. It is used by clients like glabel that just
90  *    want to check for possible filesystem types. Using UFS_NOCSUM
91  *    skips the superblock checks for csum data which allows superblocks
92  *    that have corrupted csum data to be read and used.
93  *
94  * UFS_NOHASHFAIL will note that the check hash is wrong but will still
95  *    return the superblock. This is used by the bootstrap code to
96  *    give the system a chance to come up so that fsck can be run to
97  *    correct the problem.
98  *
99  * UFS_NOWARNFAIL will warn about inconsistencies but still return the
100  *    superblock. It includes UFS_NOHASHFAIL. UFS_NOWARNFAIL is used by
101  *    programs like fsck_ffs(8) to debug broken filesystems.
102  *
103  * UFS_FSRONLY will only validate the superblock fields needed to
104  *    calculate where the backup filesystem superblocks are located.
105  *    If these values pass their validation tests, then the superblock
106  *    is returned. This flag is used as part of the attempt to find
107  *    alternate superblocks when using ffs_sbsearch().
108  */
109 #define	UFS_NOHASHFAIL	0x0001	/* Ignore check-hash failure */
110 #define	UFS_NOWARNFAIL	0x0003	/* Ignore non-fatal inconsistencies */
111 #define	UFS_NOMSG	0x0004	/* Print no error message */
112 #define	UFS_NOCSUM	0x0008	/* Read just the superblock without csum */
113 #define	UFS_FSRONLY	0x0010	/* Validate only values needed for recovery
114 				   of alternate superblocks */
115 #define	UFS_ALTSBLK	0x1000	/* Flag used internally */
116 
117 /*
118  * Max number of fragments per block. This value is NOT tweakable.
119  */
120 #define	MAXFRAG 	8
121 
122 /*
123  * Addresses stored in inodes are capable of addressing fragments
124  * of `blocks'. File system blocks of at most size MAXBSIZE can
125  * be optionally broken into 2, 4, or 8 pieces, each of which is
126  * addressable; these pieces may be DEV_BSIZE, or some multiple of
127  * a DEV_BSIZE unit.
128  *
129  * Large files consist of exclusively large data blocks.  To avoid
130  * undue wasted disk space, the last data block of a small file may be
131  * allocated as only as many fragments of a large block as are
132  * necessary.  The filesystem format retains only a single pointer
133  * to such a fragment, which is a piece of a single large block that
134  * has been divided.  The size of such a fragment is determinable from
135  * information in the inode, using the ``blksize(fs, ip, lbn)'' macro.
136  *
137  * The filesystem records space availability at the fragment level;
138  * to determine block availability, aligned fragments are examined.
139  */
140 
141 /*
142  * MINBSIZE is the smallest allowable block size.
143  * In order to insure that it is possible to create files of size
144  * 2^32 with only two levels of indirection, MINBSIZE is set to 4096.
145  * MINBSIZE must be big enough to hold a cylinder group block,
146  * thus changes to (struct cg) must keep its size within MINBSIZE.
147  * Note that super blocks are always of size SBLOCKSIZE,
148  * and that both SBLOCKSIZE and MAXBSIZE must be >= MINBSIZE.
149  */
150 #define	MINBSIZE	4096
151 
152 /*
153  * The path name on which the filesystem is mounted is maintained
154  * in fs_fsmnt. MAXMNTLEN defines the amount of space allocated in
155  * the super block for this name.
156  */
157 #define	MAXMNTLEN	468
158 
159 /*
160  * The volume name for this filesystem is maintained in fs_volname.
161  * MAXVOLLEN defines the length of the buffer allocated.
162  */
163 #define	MAXVOLLEN	32
164 
165 /*
166  * There is a 128-byte region in the superblock reserved for in-core
167  * pointers to summary information. Originally this included an array
168  * of pointers to blocks of struct csum; now there are just a few
169  * pointers and the remaining space is padded with fs_ocsp[].
170  *
171  * NOCSPTRS determines the size of this padding. Historically this
172  * space was used to store pointers to structures that summaried
173  * filesystem usage and layout information. However, these pointers
174  * left various kernel pointers in the superblock which made otherwise
175  * identical superblocks appear to have differences. So, all the
176  * pointers in the superblock were moved to a fs_summary_info structure
177  * reducing the superblock to having only a single pointer to this
178  * structure. When writing the superblock to disk, this pointer is
179  * temporarily NULL'ed out so that the kernel pointer will not appear
180  * in the on-disk copy of the superblock.
181  */
182 #define	NOCSPTRS	((128 / sizeof(void *)) - 1)
183 
184 /*
185  * A summary of contiguous blocks of various sizes is maintained
186  * in each cylinder group. Normally this is set by the initial
187  * value of fs_maxcontig. To conserve space, a maximum summary size
188  * is set by FS_MAXCONTIG.
189  */
190 #define	FS_MAXCONTIG	16
191 
192 /*
193  * MINFREE gives the minimum acceptable percentage of filesystem
194  * blocks which may be free. If the freelist drops below this level
195  * only the superuser may continue to allocate blocks. This may
196  * be set to 0 if no reserve of free blocks is deemed necessary,
197  * however throughput drops by fifty percent if the filesystem
198  * is run at between 95% and 100% full; thus the minimum default
199  * value of fs_minfree is 5%. However, to get good clustering
200  * performance, 10% is a better choice. hence we use 10% as our
201  * default value. With 10% free space, fragmentation is not a
202  * problem, so we choose to optimize for time.
203  */
204 #define	MINFREE		8
205 #define	DEFAULTOPT	FS_OPTTIME
206 
207 /*
208  * Grigoriy Orlov <gluk@ptci.ru> has done some extensive work to fine
209  * tune the layout preferences for directories within a filesystem.
210  * His algorithm can be tuned by adjusting the following parameters
211  * which tell the system the average file size and the average number
212  * of files per directory. These defaults are well selected for typical
213  * filesystems, but may need to be tuned for odd cases like filesystems
214  * being used for squid caches or news spools.
215  */
216 #define	AVFILESIZ	16384	/* expected average file size */
217 #define	AFPDIR		64	/* expected number of files per directory */
218 
219 /*
220  * The maximum number of snapshot nodes that can be associated
221  * with each filesystem. This limit affects only the number of
222  * snapshot files that can be recorded within the superblock so
223  * that they can be found when the filesystem is mounted. However,
224  * maintaining too many will slow the filesystem performance, so
225  * having this limit is a good idea.
226  */
227 #define	FSMAXSNAP 20
228 
229 /*
230  * Used to identify special blocks in snapshots:
231  *
232  * BLK_NOCOPY - A block that was unallocated at the time the snapshot
233  *	was taken, hence does not need to be copied when written.
234  * BLK_SNAP - A block held by another snapshot that is not needed by this
235  *	snapshot. When the other snapshot is freed, the BLK_SNAP entries
236  *	are converted to BLK_NOCOPY. These are needed to allow fsck to
237  *	identify blocks that are in use by other snapshots (which are
238  *	expunged from this snapshot).
239  */
240 #define	BLK_NOCOPY ((ufs2_daddr_t)(1))
241 #define	BLK_SNAP ((ufs2_daddr_t)(2))
242 
243 /*
244  * Sysctl values for the fast filesystem.
245  */
246 #define	FFS_ADJ_REFCNT		 1	/* adjust inode reference count */
247 #define	FFS_ADJ_BLKCNT		 2	/* adjust inode used block count */
248 #define	FFS_BLK_FREE		 3	/* free range of blocks in map */
249 #define	FFS_DIR_FREE		 4	/* free specified dir inodes in map */
250 #define	FFS_FILE_FREE		 5	/* free specified file inodes in map */
251 #define	FFS_SET_FLAGS		 6	/* set filesystem flags */
252 #define	FFS_ADJ_NDIR		 7	/* adjust number of directories */
253 #define	FFS_ADJ_NBFREE		 8	/* adjust number of free blocks */
254 #define	FFS_ADJ_NIFREE		 9	/* adjust number of free inodes */
255 #define	FFS_ADJ_NFFREE		10 	/* adjust number of free frags */
256 #define	FFS_ADJ_NUMCLUSTERS	11	/* adjust number of free clusters */
257 #define	FFS_SET_CWD		12	/* set current directory */
258 #define	FFS_SET_DOTDOT		13	/* set inode number for ".." */
259 #define	FFS_UNLINK		14	/* remove a name in the filesystem */
260 /* Was FFS_SET_INODE		15 */
261 /* Was FFS_SET_BUFOUTPUT	16 */
262 #define	FFS_SET_SIZE		17	/* set inode size */
263 #define	FFS_ADJ_DEPTH		18	/* adjust directory inode depth */
264 #define	FFS_MAXID		18	/* number of valid ffs ids */
265 
266 /*
267  * Command structure passed in to the filesystem to adjust filesystem values.
268  */
269 #define	FFS_CMD_VERSION		0x19790518	/* version ID */
270 struct fsck_cmd {
271 	int32_t	version;	/* version of command structure */
272 	int32_t	handle;		/* reference to filesystem to be changed */
273 	int64_t	value;		/* inode or block number to be affected */
274 	int64_t	size;		/* amount or range to be adjusted */
275 	int64_t	spare;		/* reserved for future use */
276 };
277 
278 /*
279  * A recovery structure placed at the end of the boot block area by newfs
280  * that can be used by fsck to search for alternate superblocks.
281  */
282 struct fsrecovery {
283 	int32_t	fsr_magic;	/* magic number */
284 	int32_t	fsr_fsbtodb;	/* fsbtodb and dbtofsb shift constant */
285 	int32_t	fsr_sblkno;	/* offset of super-block in filesys */
286 	int32_t	fsr_fpg;	/* blocks per group * fs_frag */
287 	uint32_t fsr_ncg;	/* number of cylinder groups */
288 };
289 
290 /*
291  * Per cylinder group information; summarized in blocks allocated
292  * from first cylinder group data blocks.  These blocks have to be
293  * read in from fs_csaddr (size fs_cssize) in addition to the
294  * super block.
295  */
296 struct csum {
297 	int32_t	cs_ndir;		/* number of directories */
298 	int32_t	cs_nbfree;		/* number of free blocks */
299 	int32_t	cs_nifree;		/* number of free inodes */
300 	int32_t	cs_nffree;		/* number of free frags */
301 };
302 struct csum_total {
303 	int64_t	cs_ndir;		/* number of directories */
304 	int64_t	cs_nbfree;		/* number of free blocks */
305 	int64_t	cs_nifree;		/* number of free inodes */
306 	int64_t	cs_nffree;		/* number of free frags */
307 	int64_t	cs_numclusters;		/* number of free clusters */
308 	int64_t	cs_spare[3];		/* future expansion */
309 };
310 
311 /*
312  * Pointers to super block summary information. Placed in a separate
313  * structure so there is just one pointer in the superblock.
314  *
315  * The pointers in this structure are used as follows:
316  *   fs_contigdirs references an array that tracks the creation of new
317  *	directories
318  *   fs_csp references a contiguous array of struct csum for
319  *	all cylinder groups
320  *   fs_maxcluster references an array of cluster sizes that is computed
321  *	as cylinder groups are inspected
322  *   fs_active is used when creating snapshots; it points to a bitmap
323  *	of cylinder groups for which the free-block bitmap has changed
324  *	since the snapshot operation began.
325  */
326 struct fs_summary_info {
327 	uint8_t	*si_contigdirs;		/* (u) # of contig. allocated dirs */
328 	struct	csum *si_csp;		/* (u) cg summary info buffer */
329 	int32_t	*si_maxcluster;		/* (u) max cluster in each cyl group */
330 	uint64_t *si_active;		/* (u) used by snapshots to track fs */
331 };
332 #define fs_contigdirs	fs_si->si_contigdirs
333 #define fs_csp		fs_si->si_csp
334 #define fs_maxcluster	fs_si->si_maxcluster
335 #define fs_active	fs_si->si_active
336 
337 /*
338  * Super block for an FFS filesystem.
339  */
340 struct fs {
341 	int32_t	 fs_firstfield;		/* historic filesystem linked list, */
342 	int32_t	 fs_unused_1;		/*     used for incore super blocks */
343 	int32_t	 fs_sblkno;		/* offset of super-block in filesys */
344 	int32_t	 fs_cblkno;		/* offset of cyl-block in filesys */
345 	int32_t	 fs_iblkno;		/* offset of inode-blocks in filesys */
346 	int32_t	 fs_dblkno;		/* offset of first data after cg */
347 	int32_t	 fs_old_cgoffset;	/* cylinder group offset in cylinder */
348 	int32_t	 fs_old_cgmask;		/* used to calc mod fs_ntrak */
349 	int32_t  fs_old_time;		/* last time written */
350 	int32_t	 fs_old_size;		/* number of blocks in fs */
351 	int32_t	 fs_old_dsize;		/* number of data blocks in fs */
352 	uint32_t fs_ncg;		/* number of cylinder groups */
353 	int32_t	 fs_bsize;		/* size of basic blocks in fs */
354 	int32_t	 fs_fsize;		/* size of frag blocks in fs */
355 	int32_t	 fs_frag;		/* number of frags in a block in fs */
356 /* these are configuration parameters */
357 	int32_t	 fs_minfree;		/* minimum percentage of free blocks */
358 	int32_t	 fs_old_rotdelay;	/* num of ms for optimal next block */
359 	int32_t	 fs_old_rps;		/* disk revolutions per second */
360 /* these fields can be computed from the others */
361 	int32_t	 fs_bmask;		/* ``blkoff'' calc of blk offsets */
362 	int32_t	 fs_fmask;		/* ``fragoff'' calc of frag offsets */
363 	int32_t	 fs_bshift;		/* ``lblkno'' calc of logical blkno */
364 	int32_t	 fs_fshift;		/* ``numfrags'' calc number of frags */
365 /* these are configuration parameters */
366 	int32_t	 fs_maxcontig;		/* max number of contiguous blks */
367 	int32_t	 fs_maxbpg;		/* max number of blks per cyl group */
368 /* these fields can be computed from the others */
369 	int32_t	 fs_fragshift;		/* block to frag shift */
370 	int32_t	 fs_fsbtodb;		/* fsbtodb and dbtofsb shift constant */
371 	int32_t	 fs_sbsize;		/* actual size of super block */
372 	int32_t	 fs_spare1[2];		/* old fs_csmask */
373 					/* old fs_csshift */
374 	int32_t	 fs_nindir;		/* value of NINDIR */
375 	uint32_t fs_inopb;		/* value of INOPB */
376 	int32_t	 fs_old_nspf;		/* value of NSPF */
377 /* yet another configuration parameter */
378 	int32_t	 fs_optim;		/* optimization preference, see below */
379 	int32_t	 fs_old_npsect;		/* # sectors/track including spares */
380 	int32_t	 fs_old_interleave;	/* hardware sector interleave */
381 	int32_t	 fs_old_trackskew;	/* sector 0 skew, per track */
382 	int32_t	 fs_id[2];		/* unique filesystem id */
383 /* sizes determined by number of cylinder groups and their sizes */
384 	int32_t	 fs_old_csaddr;		/* blk addr of cyl grp summary area */
385 	int32_t	 fs_cssize;		/* size of cyl grp summary area */
386 	int32_t	 fs_cgsize;		/* cylinder group size */
387 	int32_t	 fs_spare2;		/* old fs_ntrak */
388 	int32_t	 fs_old_nsect;		/* sectors per track */
389 	int32_t  fs_old_spc;		/* sectors per cylinder */
390 	int32_t	 fs_old_ncyl;		/* cylinders in filesystem */
391 	int32_t	 fs_old_cpg;		/* cylinders per group */
392 	uint32_t fs_ipg;		/* inodes per group */
393 	int32_t	 fs_fpg;		/* blocks per group * fs_frag */
394 /* this data must be re-computed after crashes */
395 	struct	csum fs_old_cstotal;	/* cylinder summary information */
396 /* these fields are cleared at mount time */
397 	int8_t   fs_fmod;		/* super block modified flag */
398 	int8_t   fs_clean;		/* filesystem is clean flag */
399 	int8_t 	 fs_ronly;		/* mounted read-only flag */
400 	int8_t   fs_old_flags;		/* old FS_ flags */
401 	uint8_t	 fs_fsmnt[MAXMNTLEN];	/* name mounted on */
402 	uint8_t	 fs_volname[MAXVOLLEN];	/* volume name */
403 	uint64_t fs_swuid;		/* system-wide uid */
404 	int32_t  fs_pad;		/* due to alignment of fs_swuid */
405 /* these fields retain the current block allocation info */
406 	int32_t	 fs_cgrotor;		/* last cg searched */
407 	void 	*fs_ocsp[NOCSPTRS];	/* padding; was list of fs_cs buffers */
408 	struct	 fs_summary_info *fs_si;/* In-core pointer to summary info */
409 	int32_t	 fs_old_cpc;		/* cyl per cycle in postbl */
410 	int32_t	 fs_maxbsize;		/* maximum blocking factor permitted */
411 	int64_t	 fs_unrefs;		/* number of unreferenced inodes */
412 	int64_t  fs_providersize;	/* size of underlying GEOM provider */
413 	int64_t	 fs_metaspace;		/* size of area reserved for metadata */
414 	int64_t	 fs_sparecon64[13];	/* old rotation block list head */
415 	int64_t	 fs_sblockactualloc;	/* byte offset of this superblock */
416 	int64_t	 fs_sblockloc;		/* byte offset of standard superblock */
417 	struct	csum_total fs_cstotal;	/* (u) cylinder summary information */
418 	ufs_time_t fs_time;		/* last time written */
419 	int64_t	 fs_size;		/* number of blocks in fs */
420 	int64_t	 fs_dsize;		/* number of data blocks in fs */
421 	ufs2_daddr_t fs_csaddr;		/* blk addr of cyl grp summary area */
422 	int64_t	 fs_pendingblocks;	/* (u) blocks being freed */
423 	uint32_t fs_pendinginodes;	/* (u) inodes being freed */
424 	uint32_t fs_snapinum[FSMAXSNAP];/* list of snapshot inode numbers */
425 	uint32_t fs_avgfilesize;	/* expected average file size */
426 	uint32_t fs_avgfpdir;		/* expected # of files per directory */
427 	int32_t	 fs_save_cgsize;	/* save real cg size to use fs_bsize */
428 	ufs_time_t fs_mtime;		/* Last mount or fsck time. */
429 	int32_t  fs_sujfree;		/* SUJ free list */
430 	int32_t	 fs_sparecon32[21];	/* reserved for future constants */
431 	uint32_t fs_ckhash;		/* if CK_SUPERBLOCK, its check-hash */
432 	uint32_t fs_metackhash;	/* metadata check-hash, see CK_ below */
433 	int32_t  fs_flags;		/* see FS_ flags below */
434 	int32_t	 fs_contigsumsize;	/* size of cluster summary array */
435 	int32_t	 fs_maxsymlinklen;	/* max length of an internal symlink */
436 	int32_t	 fs_old_inodefmt;	/* format of on-disk inodes */
437 	uint64_t fs_maxfilesize;	/* maximum representable file size */
438 	int64_t	 fs_qbmask;		/* ~fs_bmask for use with 64-bit size */
439 	int64_t	 fs_qfmask;		/* ~fs_fmask for use with 64-bit size */
440 	int32_t	 fs_state;		/* validate fs_clean field */
441 	int32_t	 fs_old_postblformat;	/* format of positional layout tables */
442 	int32_t	 fs_old_nrpos;		/* number of rotational positions */
443 	int32_t	 fs_spare5[2];		/* old fs_postbloff */
444 					/* old fs_rotbloff */
445 	int32_t	 fs_magic;		/* magic number */
446 };
447 
448 /* Sanity checking. */
449 #ifdef CTASSERT
450 CTASSERT(sizeof(struct fs) == 1376);
451 #endif
452 
453 /*
454  * Filesystem identification
455  */
456 #define	FS_UFS1_MAGIC	0x011954	/* UFS1 fast filesystem magic number */
457 #define	FS_UFS2_MAGIC	0x19540119	/* UFS2 fast filesystem magic number */
458 #define	FS_BAD_MAGIC	0x19960408	/* UFS incomplete newfs magic number */
459 #define	FS_42INODEFMT	-1		/* 4.2BSD inode format */
460 #define	FS_44INODEFMT	2		/* 4.4BSD inode format */
461 
462 /*
463  * Preference for optimization.
464  */
465 #define	FS_OPTTIME	0	/* minimize allocation time */
466 #define	FS_OPTSPACE	1	/* minimize disk fragmentation */
467 
468 /*
469  * Filesystem flags.
470  *
471  * The FS_UNCLEAN flag is set by the kernel when the filesystem was
472  * mounted with fs_clean set to zero. The FS_DOSOFTDEP flag indicates
473  * that the filesystem should be managed by the soft updates code.
474  * Note that the FS_NEEDSFSCK flag is set and cleared by the fsck
475  * utility. It is set when background fsck finds an unexpected
476  * inconsistency which requires a traditional foreground fsck to be
477  * run. Such inconsistencies should only be found after an uncorrectable
478  * disk error. The FS_NEEDSFSCK can also be set when a mounted filesystem
479  * discovers an internal inconsistency such as freeing a freed inode.
480  * A foreground fsck will clear the FS_NEEDSFSCK flag when it has
481  * successfully cleaned up the filesystem. The kernel uses this
482  * flag to enforce that inconsistent filesystems be mounted read-only.
483  *
484  * The FS_METACKHASH flag when set indicates that the kernel maintains
485  * one or more check hashes. The actual set of supported check hashes
486  * is stored in the fs_metackhash field. Kernels that do not support
487  * check hashes clear the FS_METACKHASH flag to indicate that the
488  * check hashes need to be rebuilt (by fsck) before they can be used.
489  *
490  * When a filesystem is mounted, any flags not included in FS_SUPPORTED
491  * are cleared. This lets newer features know that the filesystem has
492  * been run on an older version of the filesystem and thus that data
493  * structures associated with those features are out-of-date and need
494  * to be rebuilt.
495  *
496  * FS_ACLS indicates that POSIX.1e ACLs are administratively enabled
497  * for the file system, so they should be loaded from extended attributes,
498  * observed for access control purposes, and be administered by object
499  * owners.  FS_NFS4ACLS indicates that NFSv4 ACLs are administratively
500  * enabled.  This flag is mutually exclusive with FS_ACLS.  FS_MULTILABEL
501  * indicates that the TrustedBSD MAC Framework should attempt to back MAC
502  * labels into extended attributes on the file system rather than maintain
503  * a single mount label for all objects.
504  */
505 #define	FS_UNCLEAN	0x00000001 /* filesystem not clean at mount */
506 #define	FS_DOSOFTDEP	0x00000002 /* filesystem using soft dependencies */
507 #define	FS_NEEDSFSCK	0x00000004 /* filesystem needs sync fsck before mount */
508 #define	FS_SUJ       	0x00000008 /* Filesystem using softupdate journal */
509 #define	FS_ACLS		0x00000010 /* file system has POSIX.1e ACLs enabled */
510 #define	FS_MULTILABEL	0x00000020 /* file system is MAC multi-label */
511 #define	FS_GJOURNAL	0x00000040 /* gjournaled file system */
512 #define	FS_FLAGS_UPDATED 0x0000080 /* flags have been moved to new location */
513 #define	FS_NFS4ACLS	0x00000100 /* file system has NFSv4 ACLs enabled */
514 #define	FS_METACKHASH	0x00000200 /* kernel supports metadata check hashes */
515 #define	FS_TRIM		0x00000400 /* issue BIO_DELETE for deleted blocks */
516 #define	FS_SUPPORTED	0x00FFFFFF /* supported flags, others cleared at mount*/
517 /*
518  * Things that we may someday support, but currently do not.
519  * These flags are all cleared so we know if we ran on a kernel
520  * that does not support them.
521  */
522 #define	FS_INDEXDIRS	0x01000000 /* kernel supports indexed directories */
523 #define	FS_VARBLKSIZE	0x02000000 /* kernel supports variable block sizes */
524 #define	FS_COOLOPT1	0x04000000 /* kernel supports cool option 1 */
525 #define	FS_COOLOPT2	0x08000000 /* kernel supports cool option 2 */
526 #define	FS_COOLOPT3	0x10000000 /* kernel supports cool option 3 */
527 #define	FS_COOLOPT4	0x20000000 /* kernel supports cool option 4 */
528 #define	FS_COOLOPT5	0x40000000 /* kernel supports cool option 5 */
529 #define	FS_COOLOPT6	0x80000000 /* kernel supports cool option 6 */
530 
531 /*
532  * The fs_metackhash field indicates the types of metadata check-hash
533  * that are maintained for a filesystem. Not all filesystems check-hash
534  * all metadata.
535  */
536 #define	CK_SUPERBLOCK	0x0001	/* the superblock */
537 #define	CK_CYLGRP	0x0002	/* the cylinder groups */
538 #define	CK_INODE	0x0004	/* inodes */
539 #define	CK_INDIR	0x0008	/* indirect blocks */
540 #define	CK_DIR		0x0010	/* directory contents */
541 #define	CK_SUPPORTED	0x0007	/* supported flags, others cleared at mount */
542 /*
543  * The BX_FSPRIV buffer b_xflags are used to track types of data in buffers.
544  */
545 #define	BX_SUPERBLOCK	0x00010000	/* superblock */
546 #define	BX_CYLGRP	0x00020000	/* cylinder groups */
547 #define	BX_INODE	0x00040000	/* inodes */
548 #define	BX_INDIR	0x00080000	/* indirect blocks */
549 #define	BX_DIR		0x00100000	/* directory contents */
550 
551 #define	PRINT_UFS_BUF_XFLAGS "\20\25dir\24indir\23inode\22cylgrp\21superblock"
552 
553 /*
554  * Macros to access bits in the fs_active array.
555  */
556 #define	ACTIVECGNUM(fs, cg)  ((fs)->fs_active[(cg) / (NBBY * sizeof(uint64_t))])
557 #define	ACTIVECGOFF(cg)	     (1 << ((cg) % (NBBY * sizeof(uint64_t))))
558 #define	ACTIVESET(fs, cg)    do {					\
559 	if ((fs)->fs_active)						\
560 		ACTIVECGNUM((fs), (cg)) |= ACTIVECGOFF((cg));		\
561 } while (0)
562 #define	ACTIVECLEAR(fs, cg)	do {					\
563 	if ((fs)->fs_active)						\
564 		ACTIVECGNUM((fs), (cg)) &= ~ACTIVECGOFF((cg));		\
565 } while (0)
566 
567 /*
568  * The size of a cylinder group is calculated by CGSIZE. The maximum size
569  * is limited by the fact that cylinder groups are at most one block.
570  * Its size is derived from the size of the maps maintained in the
571  * cylinder group and the (struct cg) size.
572  */
573 #define	CGSIZE(fs) \
574     /* base cg */	(sizeof(struct cg) + \
575     /* old btotoff */	(fs)->fs_old_cpg * sizeof(int32_t) + \
576     /* old boff */	(fs)->fs_old_cpg * sizeof(uint16_t) + \
577     /* inode map */	howmany((fs)->fs_ipg, NBBY) + \
578     /* block map */	howmany((fs)->fs_fpg, NBBY) + sizeof(int32_t) + \
579     /* if present */	((fs)->fs_contigsumsize <= 0 ? 0 : \
580     /* cluster sum */	(fs)->fs_contigsumsize * sizeof(int32_t) + \
581     /* cluster map */	howmany(fragstoblks(fs, (fs)->fs_fpg), NBBY)))
582 
583 /*
584  * The minimal number of cylinder groups that should be created.
585  */
586 #define	MINCYLGRPS	4
587 
588 /*
589  * Convert cylinder group to base address of its global summary info.
590  */
591 #define	fs_cs(fs, indx) fs_csp[indx]
592 
593 /*
594  * Cylinder group block for a filesystem.
595  */
596 #define	CG_MAGIC	0x090255
597 struct cg {
598 	int32_t	 cg_firstfield;		/* historic cyl groups linked list */
599 	int32_t	 cg_magic;		/* magic number */
600 	int32_t  cg_old_time;		/* time last written */
601 	uint32_t cg_cgx;		/* we are the cgx'th cylinder group */
602 	int16_t	 cg_old_ncyl;		/* number of cyl's this cg */
603 	int16_t  cg_old_niblk;		/* number of inode blocks this cg */
604 	uint32_t cg_ndblk;		/* number of data blocks this cg */
605 	struct	 csum cg_cs;		/* cylinder summary information */
606 	uint32_t cg_rotor;		/* position of last used block */
607 	uint32_t cg_frotor;		/* position of last used frag */
608 	uint32_t cg_irotor;		/* position of last used inode */
609 	uint32_t cg_frsum[MAXFRAG];	/* counts of available frags */
610 	int32_t	 cg_old_btotoff;	/* (int32) block totals per cylinder */
611 	int32_t	 cg_old_boff;		/* (uint16) free block positions */
612 	uint32_t cg_iusedoff;		/* (uint8) used inode map */
613 	uint32_t cg_freeoff;		/* (uint8) free block map */
614 	uint32_t cg_nextfreeoff;	/* (uint8) next available space */
615 	uint32_t cg_clustersumoff;	/* (uint32) counts of avail clusters */
616 	uint32_t cg_clusteroff;		/* (uint8) free cluster map */
617 	uint32_t cg_nclusterblks;	/* number of clusters this cg */
618 	uint32_t cg_niblk;		/* number of inode blocks this cg */
619 	uint32_t cg_initediblk;		/* last initialized inode */
620 	uint32_t cg_unrefs;		/* number of unreferenced inodes */
621 	int32_t	 cg_sparecon32[1];	/* reserved for future use */
622 	uint32_t cg_ckhash;		/* check-hash of this cg */
623 	ufs_time_t cg_time;		/* time last written */
624 	int64_t	 cg_sparecon64[3];	/* reserved for future use */
625 	/* actually longer - space used for cylinder group maps */
626 };
627 
628 /*
629  * Macros for access to cylinder group array structures
630  */
631 #define	cg_chkmagic(cgp) ((cgp)->cg_magic == CG_MAGIC)
632 #define	cg_inosused(cgp) \
633     ((uint8_t *)((uint8_t *)(cgp) + (cgp)->cg_iusedoff))
634 #define	cg_blksfree(cgp) \
635     ((uint8_t *)((uint8_t *)(cgp) + (cgp)->cg_freeoff))
636 #define	cg_clustersfree(cgp) \
637     ((uint8_t *)((uint8_t *)(cgp) + (cgp)->cg_clusteroff))
638 #define	cg_clustersum(cgp) \
639     ((int32_t *)((uintptr_t)(cgp) + (cgp)->cg_clustersumoff))
640 
641 /*
642  * Turn filesystem block numbers into disk block addresses.
643  * This maps filesystem blocks to device size blocks.
644  */
645 #define	fsbtodb(fs, b)	((daddr_t)(b) << (fs)->fs_fsbtodb)
646 #define	dbtofsb(fs, b)	((b) >> (fs)->fs_fsbtodb)
647 
648 /*
649  * Cylinder group macros to locate things in cylinder groups.
650  * They calc filesystem addresses of cylinder group data structures.
651  */
652 #define	cgbase(fs, c)	(((ufs2_daddr_t)(fs)->fs_fpg) * (c))
653 #define	cgdata(fs, c)	(cgdmin(fs, c) + (fs)->fs_metaspace)	/* data zone */
654 #define	cgmeta(fs, c)	(cgdmin(fs, c))				/* meta data */
655 #define	cgdmin(fs, c)	(cgstart(fs, c) + (fs)->fs_dblkno)	/* 1st data */
656 #define	cgimin(fs, c)	(cgstart(fs, c) + (fs)->fs_iblkno)	/* inode blk */
657 #define	cgsblock(fs, c)	(cgstart(fs, c) + (fs)->fs_sblkno)	/* super blk */
658 #define	cgtod(fs, c)	(cgstart(fs, c) + (fs)->fs_cblkno)	/* cg block */
659 #define	cgstart(fs, c)							\
660        ((fs)->fs_magic == FS_UFS2_MAGIC ? cgbase(fs, c) :		\
661        (cgbase(fs, c) + (fs)->fs_old_cgoffset * ((c) & ~((fs)->fs_old_cgmask))))
662 
663 /*
664  * Macros for handling inode numbers:
665  *     inode number to filesystem block offset.
666  *     inode number to cylinder group number.
667  *     inode number to filesystem block address.
668  */
669 #define	ino_to_cg(fs, x)	(((ino_t)(x)) / (fs)->fs_ipg)
670 #define	ino_to_fsba(fs, x)						\
671 	((ufs2_daddr_t)(cgimin(fs, ino_to_cg(fs, (ino_t)(x))) +		\
672 	    (blkstofrags((fs), ((((ino_t)(x)) % (fs)->fs_ipg) / INOPB(fs))))))
673 #define	ino_to_fsbo(fs, x)	(((ino_t)(x)) % INOPB(fs))
674 
675 /*
676  * Give cylinder group number for a filesystem block.
677  * Give cylinder group block number for a filesystem block.
678  */
679 #define	dtog(fs, d)	((d) / (fs)->fs_fpg)
680 #define	dtogd(fs, d)	((d) % (fs)->fs_fpg)
681 
682 /*
683  * Extract the bits for a block from a map.
684  * Compute the cylinder and rotational position of a cyl block addr.
685  */
686 #define	blkmap(fs, map, loc) \
687     (((map)[(loc) / NBBY] >> ((loc) % NBBY)) & (0xff >> (NBBY - (fs)->fs_frag)))
688 
689 /*
690  * The following macros optimize certain frequently calculated
691  * quantities by using shifts and masks in place of divisions
692  * modulos and multiplications.
693  */
694 #define	blkoff(fs, loc)		/* calculates (loc % fs->fs_bsize) */ \
695 	((loc) & (fs)->fs_qbmask)
696 #define	fragoff(fs, loc)	/* calculates (loc % fs->fs_fsize) */ \
697 	((loc) & (fs)->fs_qfmask)
698 #define	lfragtosize(fs, frag)	/* calculates ((off_t)frag * fs->fs_fsize) */ \
699 	(((off_t)(frag)) << (fs)->fs_fshift)
700 #define	lblktosize(fs, blk)	/* calculates ((off_t)blk * fs->fs_bsize) */ \
701 	(((off_t)(blk)) << (fs)->fs_bshift)
702 /* Use this only when `blk' is known to be small, e.g., < UFS_NDADDR. */
703 #define	smalllblktosize(fs, blk)    /* calculates (blk * fs->fs_bsize) */ \
704 	((blk) << (fs)->fs_bshift)
705 #define	lblkno(fs, loc)		/* calculates (loc / fs->fs_bsize) */ \
706 	((loc) >> (fs)->fs_bshift)
707 #define	numfrags(fs, loc)	/* calculates (loc / fs->fs_fsize) */ \
708 	((loc) >> (fs)->fs_fshift)
709 #define	blkroundup(fs, size)	/* calculates roundup(size, fs->fs_bsize) */ \
710 	(((size) + (fs)->fs_qbmask) & (fs)->fs_bmask)
711 #define	fragroundup(fs, size)	/* calculates roundup(size, fs->fs_fsize) */ \
712 	(((size) + (fs)->fs_qfmask) & (fs)->fs_fmask)
713 #define	fragstoblks(fs, frags)	/* calculates (frags / fs->fs_frag) */ \
714 	((frags) >> (fs)->fs_fragshift)
715 #define	blkstofrags(fs, blks)	/* calculates (blks * fs->fs_frag) */ \
716 	((blks) << (fs)->fs_fragshift)
717 #define	fragnum(fs, fsb)	/* calculates (fsb % fs->fs_frag) */ \
718 	((fsb) & ((fs)->fs_frag - 1))
719 #define	blknum(fs, fsb)		/* calculates rounddown(fsb, fs->fs_frag) */ \
720 	((fsb) &~ ((fs)->fs_frag - 1))
721 
722 /*
723  * Determine the number of available frags given a
724  * percentage to hold in reserve.
725  */
726 #define	freespace(fs, percentreserved) \
727 	(blkstofrags((fs), (fs)->fs_cstotal.cs_nbfree) + \
728 	(fs)->fs_cstotal.cs_nffree - \
729 	(((off_t)((fs)->fs_dsize)) * (percentreserved) / 100))
730 
731 /*
732  * Determining the size of a file block in the filesystem.
733  */
734 #define	blksize(fs, ip, lbn) \
735 	(((lbn) >= UFS_NDADDR || (ip)->i_size >= \
736 	    (uint64_t)smalllblktosize(fs, (lbn) + 1)) \
737 	    ? (fs)->fs_bsize \
738 	    : (fragroundup(fs, blkoff(fs, (ip)->i_size))))
739 #define	sblksize(fs, size, lbn) \
740 	(((lbn) >= UFS_NDADDR || (size) >= ((lbn) + 1) << (fs)->fs_bshift) \
741 	  ? (fs)->fs_bsize \
742 	  : (fragroundup(fs, blkoff(fs, (size)))))
743 
744 /*
745  * Number of indirects in a filesystem block.
746  */
747 #define	NINDIR(fs)	((fs)->fs_nindir)
748 
749 /*
750  * Indirect lbns are aligned on UFS_NDADDR addresses where single indirects
751  * are the negated address of the lowest lbn reachable, double indirects
752  * are this lbn - 1 and triple indirects are this lbn - 2.  This yields
753  * an unusual bit order to determine level.
754  */
755 static inline int
756 lbn_level(ufs_lbn_t lbn)
757 {
758 	if (lbn >= 0)
759 		return 0;
760 	switch (lbn & 0x3) {
761 	case 0:
762 		return (0);
763 	case 1:
764 		break;
765 	case 2:
766 		return (2);
767 	case 3:
768 		return (1);
769 	default:
770 		break;
771 	}
772 	return (-1);
773 }
774 
775 static inline ufs_lbn_t
776 lbn_offset(struct fs *fs, int level)
777 {
778 	ufs_lbn_t res;
779 
780 	for (res = 1; level > 0; level--)
781 		res *= NINDIR(fs);
782 	return (res);
783 }
784 
785 /*
786  * Number of inodes in a secondary storage block/fragment.
787  */
788 #define	INOPB(fs)	((fs)->fs_inopb)
789 #define	INOPF(fs)	((fs)->fs_inopb >> (fs)->fs_fragshift)
790 
791 /*
792  * Softdep journal record format.
793  */
794 #define	JOP_UNKNOWN	0	/* JOP operation is unknown */
795 #define	JOP_ADDREF	1	/* Add a reference to an inode. */
796 #define	JOP_REMREF	2	/* Remove a reference from an inode. */
797 #define	JOP_NEWBLK	3	/* Allocate a block. */
798 #define	JOP_FREEBLK	4	/* Free a block or a tree of blocks. */
799 #define	JOP_MVREF	5	/* Move a reference from one off to another. */
800 #define	JOP_TRUNC	6	/* Partial truncation record. */
801 #define	JOP_SYNC	7	/* fsync() complete record. */
802 #define	JOP_NUMJOPTYPES	8
803 #define JOP_NAMES {	\
804         "unknown",	\
805 	"JOP_ADDREF",	\
806 	"JOP_REMREF",	\
807 	"JOP_NEWBLK",	\
808 	"JOP_FREEBLK",	\
809 	"JOP_MVREF",	\
810 	"JOP_TRUNC",	\
811 	"JOP_SYNC" }
812 #define JOP_OPTYPE(op) \
813 	(op) < JOP_NUMJOPTYPES ? joptype[op] : joptype[JOP_UNKNOWN]
814 
815 #define	JREC_SIZE	32	/* Record and segment header size. */
816 
817 #define	SUJ_MIN		(4 * 1024 * 1024)	/* Minimum journal size */
818 #define	SUJ_FILE	".sujournal"		/* Journal file name */
819 
820 /*
821  * Size of the segment record header.  There is at most one for each disk
822  * block in the journal.  The segment header is followed by an array of
823  * records.  fsck depends on the first element in each record being 'op'
824  * and the second being 'ino'.  Segments may span multiple disk blocks but
825  * the header is present on each.
826  */
827 struct jsegrec {
828 	uint64_t	jsr_seq;	/* Our sequence number */
829 	uint64_t	jsr_oldest;	/* Oldest valid sequence number */
830 	uint16_t	jsr_cnt;	/* Count of valid records */
831 	uint16_t	jsr_blocks;	/* Count of device bsize blocks. */
832 	uint32_t	jsr_crc;	/* 32bit crc of the valid space */
833 	ufs_time_t	jsr_time;	/* timestamp for mount instance */
834 };
835 
836 /*
837  * Reference record.  Records a single link count modification.
838  */
839 struct jrefrec {
840 	uint32_t	jr_op;
841 	uint32_t	jr_ino;
842 	uint32_t	jr_parent;
843 	uint16_t	jr_nlink;
844 	uint16_t	jr_mode;
845 	int64_t		jr_diroff;
846 	uint64_t	jr_unused;
847 };
848 
849 /*
850  * Move record.  Records a reference moving within a directory block.  The
851  * nlink is unchanged but we must search both locations.
852  */
853 struct jmvrec {
854 	uint32_t	jm_op;
855 	uint32_t	jm_ino;
856 	uint32_t	jm_parent;
857 	uint16_t	jm_unused;
858 	int64_t		jm_oldoff;
859 	int64_t		jm_newoff;
860 };
861 
862 /*
863  * Block record.  A set of frags or tree of blocks starting at an indirect are
864  * freed or a set of frags are allocated.
865  */
866 struct jblkrec {
867 	uint32_t	jb_op;
868 	uint32_t	jb_ino;
869 	ufs2_daddr_t	jb_blkno;
870 	ufs_lbn_t	jb_lbn;
871 	uint16_t	jb_frags;
872 	uint16_t	jb_oldfrags;
873 	uint32_t	jb_unused;
874 };
875 
876 /*
877  * Truncation record.  Records a partial truncation so that it may be
878  * completed at check time.  Also used for sync records.
879  */
880 struct jtrncrec {
881 	uint32_t	jt_op;
882 	uint32_t	jt_ino;
883 	int64_t		jt_size;
884 	uint32_t	jt_extsize;
885 	uint32_t	jt_pad[3];
886 };
887 
888 union jrec {
889 	struct jsegrec	rec_jsegrec;
890 	struct jrefrec	rec_jrefrec;
891 	struct jmvrec	rec_jmvrec;
892 	struct jblkrec	rec_jblkrec;
893 	struct jtrncrec	rec_jtrncrec;
894 };
895 
896 #ifdef CTASSERT
897 CTASSERT(sizeof(struct jsegrec) == JREC_SIZE);
898 CTASSERT(sizeof(struct jrefrec) == JREC_SIZE);
899 CTASSERT(sizeof(struct jmvrec) == JREC_SIZE);
900 CTASSERT(sizeof(struct jblkrec) == JREC_SIZE);
901 CTASSERT(sizeof(struct jtrncrec) == JREC_SIZE);
902 CTASSERT(sizeof(union jrec) == JREC_SIZE);
903 #endif
904 
905 extern int inside[], around[];
906 extern uint8_t *fragtbl[];
907 
908 /*
909  * IOCTLs used for filesystem write suspension.
910  */
911 #define	UFSSUSPEND	_IOW('U', 1, fsid_t)
912 #define	UFSRESUME	_IO('U', 2)
913 
914 #endif
915