xref: /freebsd/sys/ufs/ffs/ffs_subr.c (revision 7815283df299be63807225a9fe9b6e54406eae28)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1989, 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  *	@(#)ffs_subr.c	8.5 (Berkeley) 3/21/95
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include <sys/param.h>
38 
39 #ifndef _KERNEL
40 #include <stdio.h>
41 #include <string.h>
42 #include <stdlib.h>
43 #include <time.h>
44 #include <sys/errno.h>
45 #include <ufs/ufs/dinode.h>
46 #include <ufs/ffs/fs.h>
47 
48 uint32_t calculate_crc32c(uint32_t, const void *, size_t);
49 struct malloc_type;
50 #define UFS_MALLOC(size, type, flags) malloc(size)
51 #define UFS_FREE(ptr, type) free(ptr)
52 #define UFS_TIME time(NULL)
53 
54 #else /* _KERNEL */
55 #include <sys/systm.h>
56 #include <sys/lock.h>
57 #include <sys/malloc.h>
58 #include <sys/mount.h>
59 #include <sys/vnode.h>
60 #include <sys/bio.h>
61 #include <sys/buf.h>
62 #include <sys/ucred.h>
63 
64 #include <ufs/ufs/quota.h>
65 #include <ufs/ufs/inode.h>
66 #include <ufs/ufs/extattr.h>
67 #include <ufs/ufs/ufsmount.h>
68 #include <ufs/ufs/ufs_extern.h>
69 #include <ufs/ffs/ffs_extern.h>
70 #include <ufs/ffs/fs.h>
71 
72 #define UFS_MALLOC(size, type, flags) malloc(size, type, flags)
73 #define UFS_FREE(ptr, type) free(ptr, type)
74 #define UFS_TIME time_second
75 
76 /*
77  * Return buffer with the contents of block "offset" from the beginning of
78  * directory "ip".  If "res" is non-zero, fill it in with a pointer to the
79  * remaining space in the directory.
80  */
81 int
82 ffs_blkatoff(struct vnode *vp, off_t offset, char **res, struct buf **bpp)
83 {
84 	struct inode *ip;
85 	struct fs *fs;
86 	struct buf *bp;
87 	ufs_lbn_t lbn;
88 	int bsize, error;
89 
90 	ip = VTOI(vp);
91 	fs = ITOFS(ip);
92 	lbn = lblkno(fs, offset);
93 	bsize = blksize(fs, ip, lbn);
94 
95 	*bpp = NULL;
96 	error = bread(vp, lbn, bsize, NOCRED, &bp);
97 	if (error) {
98 		brelse(bp);
99 		return (error);
100 	}
101 	if (res)
102 		*res = (char *)bp->b_data + blkoff(fs, offset);
103 	*bpp = bp;
104 	return (0);
105 }
106 
107 /*
108  * Load up the contents of an inode and copy the appropriate pieces
109  * to the incore copy.
110  */
111 void
112 ffs_load_inode(struct buf *bp, struct inode *ip, struct fs *fs, ino_t ino)
113 {
114 
115 	if (I_IS_UFS1(ip)) {
116 		*ip->i_din1 =
117 		    *((struct ufs1_dinode *)bp->b_data + ino_to_fsbo(fs, ino));
118 		ip->i_mode = ip->i_din1->di_mode;
119 		ip->i_nlink = ip->i_din1->di_nlink;
120 		ip->i_size = ip->i_din1->di_size;
121 		ip->i_flags = ip->i_din1->di_flags;
122 		ip->i_gen = ip->i_din1->di_gen;
123 		ip->i_uid = ip->i_din1->di_uid;
124 		ip->i_gid = ip->i_din1->di_gid;
125 	} else {
126 		*ip->i_din2 =
127 		    *((struct ufs2_dinode *)bp->b_data + ino_to_fsbo(fs, ino));
128 		ip->i_mode = ip->i_din2->di_mode;
129 		ip->i_nlink = ip->i_din2->di_nlink;
130 		ip->i_size = ip->i_din2->di_size;
131 		ip->i_flags = ip->i_din2->di_flags;
132 		ip->i_gen = ip->i_din2->di_gen;
133 		ip->i_uid = ip->i_din2->di_uid;
134 		ip->i_gid = ip->i_din2->di_gid;
135 	}
136 }
137 #endif /* KERNEL */
138 
139 /*
140  * These are the low-level functions that actually read and write
141  * the superblock and its associated data.
142  */
143 static off_t sblock_try[] = SBLOCKSEARCH;
144 static int readsuper(void *, struct fs **, off_t, int,
145 	int (*)(void *, off_t, void **, int));
146 static uint32_t calc_sbhash(struct fs *);
147 
148 /*
149  * Read a superblock from the devfd device.
150  *
151  * If an alternate superblock is specified, it is read. Otherwise the
152  * set of locations given in the SBLOCKSEARCH list is searched for a
153  * superblock. Memory is allocated for the superblock by the readfunc and
154  * is returned. If filltype is non-NULL, additional memory is allocated
155  * of type filltype and filled in with the superblock summary information.
156  * All memory is freed when any error is returned.
157  *
158  * If a superblock is found, zero is returned. Otherwise one of the
159  * following error values is returned:
160  *     EIO: non-existent or truncated superblock.
161  *     EIO: error reading summary information.
162  *     ENOENT: no usable known superblock found.
163  *     ENOSPC: failed to allocate space for the superblock.
164  *     EINVAL: The previous newfs operation on this volume did not complete.
165  *         The administrator must complete newfs before using this volume.
166  */
167 int
168 ffs_sbget(void *devfd, struct fs **fsp, off_t altsblock,
169     struct malloc_type *filltype,
170     int (*readfunc)(void *devfd, off_t loc, void **bufp, int size))
171 {
172 	struct fs *fs;
173 	int i, error, size, blks;
174 	uint8_t *space;
175 	int32_t *lp;
176 	char *buf;
177 
178 	fs = NULL;
179 	*fsp = NULL;
180 	if (altsblock != -1) {
181 		if ((error = readsuper(devfd, &fs, altsblock, 1,
182 		     readfunc)) != 0) {
183 			if (fs != NULL)
184 				UFS_FREE(fs, filltype);
185 			return (error);
186 		}
187 	} else {
188 		for (i = 0; sblock_try[i] != -1; i++) {
189 			if ((error = readsuper(devfd, &fs, sblock_try[i], 0,
190 			     readfunc)) == 0)
191 				break;
192 			if (fs != NULL) {
193 				UFS_FREE(fs, filltype);
194 				fs = NULL;
195 			}
196 			if (error == ENOENT)
197 				continue;
198 			return (error);
199 		}
200 		if (sblock_try[i] == -1)
201 			return (ENOENT);
202 	}
203 	/*
204 	 * Read in the superblock summary information.
205 	 */
206 	size = fs->fs_cssize;
207 	blks = howmany(size, fs->fs_fsize);
208 	if (fs->fs_contigsumsize > 0)
209 		size += fs->fs_ncg * sizeof(int32_t);
210 	size += fs->fs_ncg * sizeof(u_int8_t);
211 	/* When running in libufs or libsa, UFS_MALLOC may fail */
212 	if ((space = UFS_MALLOC(size, filltype, M_WAITOK)) == NULL) {
213 		UFS_FREE(fs, filltype);
214 		return (ENOSPC);
215 	}
216 	fs->fs_csp = (struct csum *)space;
217 	for (i = 0; i < blks; i += fs->fs_frag) {
218 		size = fs->fs_bsize;
219 		if (i + fs->fs_frag > blks)
220 			size = (blks - i) * fs->fs_fsize;
221 		buf = NULL;
222 		error = (*readfunc)(devfd,
223 		    dbtob(fsbtodb(fs, fs->fs_csaddr + i)), (void **)&buf, size);
224 		if (error) {
225 			if (buf != NULL)
226 				UFS_FREE(buf, filltype);
227 			UFS_FREE(fs->fs_csp, filltype);
228 			UFS_FREE(fs, filltype);
229 			return (error);
230 		}
231 		memcpy(space, buf, size);
232 		UFS_FREE(buf, filltype);
233 		space += size;
234 	}
235 	if (fs->fs_contigsumsize > 0) {
236 		fs->fs_maxcluster = lp = (int32_t *)space;
237 		for (i = 0; i < fs->fs_ncg; i++)
238 			*lp++ = fs->fs_contigsumsize;
239 		space = (uint8_t *)lp;
240 	}
241 	size = fs->fs_ncg * sizeof(u_int8_t);
242 	fs->fs_contigdirs = (u_int8_t *)space;
243 	bzero(fs->fs_contigdirs, size);
244 	*fsp = fs;
245 	return (0);
246 }
247 
248 /*
249  * Try to read a superblock from the location specified by sblockloc.
250  * Return zero on success or an errno on failure.
251  */
252 static int
253 readsuper(void *devfd, struct fs **fsp, off_t sblockloc, int isaltsblk,
254     int (*readfunc)(void *devfd, off_t loc, void **bufp, int size))
255 {
256 	struct fs *fs;
257 	int error, res;
258 	uint32_t ckhash;
259 
260 	error = (*readfunc)(devfd, sblockloc, (void **)fsp, SBLOCKSIZE);
261 	if (error != 0)
262 		return (error);
263 	fs = *fsp;
264 	if (fs->fs_magic == FS_BAD_MAGIC)
265 		return (EINVAL);
266 	if (((fs->fs_magic == FS_UFS1_MAGIC && (isaltsblk ||
267 	      sblockloc <= SBLOCK_UFS1)) ||
268 	     (fs->fs_magic == FS_UFS2_MAGIC && (isaltsblk ||
269 	      sblockloc == fs->fs_sblockloc))) &&
270 	    fs->fs_ncg >= 1 &&
271 	    fs->fs_bsize >= MINBSIZE &&
272 	    fs->fs_bsize <= MAXBSIZE &&
273 	    fs->fs_bsize >= roundup(sizeof(struct fs), DEV_BSIZE) &&
274 	    fs->fs_sbsize <= SBLOCKSIZE) {
275 		if (fs->fs_ckhash != (ckhash = calc_sbhash(fs))) {
276 #ifdef _KERNEL
277 			res = uprintf("Superblock check-hash failed: recorded "
278 			    "check-hash 0x%x != computed check-hash 0x%x\n",
279 			    fs->fs_ckhash, ckhash);
280 #else
281 			res = 0;
282 #endif
283 			/*
284 			 * Print check-hash failure if no controlling terminal
285 			 * in kernel or always if in user-mode (libufs).
286 			 */
287 			if (res == 0)
288 				printf("Superblock check-hash failed: recorded "
289 				    "check-hash 0x%x != computed check-hash "
290 				    "0x%x\n", fs->fs_ckhash, ckhash);
291 			return (EINVAL);
292 		}
293 		/* Have to set for old filesystems that predate this field */
294 		fs->fs_sblockactualloc = sblockloc;
295 		/* Not yet any summary information */
296 		fs->fs_csp = NULL;
297 		return (0);
298 	}
299 	return (ENOENT);
300 }
301 
302 /*
303  * Write a superblock to the devfd device from the memory pointed to by fs.
304  * Write out the superblock summary information if it is present.
305  *
306  * If the write is successful, zero is returned. Otherwise one of the
307  * following error values is returned:
308  *     EIO: failed to write superblock.
309  *     EIO: failed to write superblock summary information.
310  */
311 int
312 ffs_sbput(void *devfd, struct fs *fs, off_t loc,
313     int (*writefunc)(void *devfd, off_t loc, void *buf, int size))
314 {
315 	int i, error, blks, size;
316 	uint8_t *space;
317 
318 	/*
319 	 * If there is summary information, write it first, so if there
320 	 * is an error, the superblock will not be marked as clean.
321 	 */
322 	if (fs->fs_csp != NULL) {
323 		blks = howmany(fs->fs_cssize, fs->fs_fsize);
324 		space = (uint8_t *)fs->fs_csp;
325 		for (i = 0; i < blks; i += fs->fs_frag) {
326 			size = fs->fs_bsize;
327 			if (i + fs->fs_frag > blks)
328 				size = (blks - i) * fs->fs_fsize;
329 			if ((error = (*writefunc)(devfd,
330 			     dbtob(fsbtodb(fs, fs->fs_csaddr + i)),
331 			     space, size)) != 0)
332 				return (error);
333 			space += size;
334 		}
335 	}
336 	fs->fs_fmod = 0;
337 	fs->fs_time = UFS_TIME;
338 	fs->fs_ckhash = calc_sbhash(fs);
339 	if ((error = (*writefunc)(devfd, loc, fs, fs->fs_sbsize)) != 0)
340 		return (error);
341 	return (0);
342 }
343 
344 /*
345  * Calculate the check-hash for a superblock.
346  */
347 static uint32_t
348 calc_sbhash(struct fs *fs)
349 {
350 	uint32_t ckhash, save_ckhash;
351 
352 	/*
353 	 * A filesystem that was using a superblock ckhash may be moved
354 	 * to an older kernel that does not support ckhashes. The
355 	 * older kernel will clear the FS_METACKHASH flag indicating
356 	 * that it does not update hashes. When the disk is moved back
357 	 * to a kernel capable of ckhashes it disables them on mount:
358 	 *
359 	 *	if ((fs->fs_flags & FS_METACKHASH) == 0)
360 	 *		fs->fs_metackhash = 0;
361 	 *
362 	 * This leaves (fs->fs_metackhash & CK_SUPERBLOCK) == 0) with an
363 	 * old stale value in the fs->fs_ckhash field. Thus the need to
364 	 * just accept what is there.
365 	 */
366 	if ((fs->fs_metackhash & CK_SUPERBLOCK) == 0)
367 		return (fs->fs_ckhash);
368 
369 	save_ckhash = fs->fs_ckhash;
370 	fs->fs_ckhash = 0;
371 	/*
372 	 * If newly read from disk, the caller is responsible for
373 	 * verifying that fs->fs_sbsize <= SBLOCKSIZE.
374 	 */
375 	ckhash = calculate_crc32c(~0L, (void *)fs, fs->fs_sbsize);
376 	fs->fs_ckhash = save_ckhash;
377 	return (ckhash);
378 }
379 
380 /*
381  * Update the frsum fields to reflect addition or deletion
382  * of some frags.
383  */
384 void
385 ffs_fragacct(struct fs *fs, int fragmap, int32_t fraglist[], int cnt)
386 {
387 	int inblk;
388 	int field, subfield;
389 	int siz, pos;
390 
391 	inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1;
392 	fragmap <<= 1;
393 	for (siz = 1; siz < fs->fs_frag; siz++) {
394 		if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0)
395 			continue;
396 		field = around[siz];
397 		subfield = inside[siz];
398 		for (pos = siz; pos <= fs->fs_frag; pos++) {
399 			if ((fragmap & field) == subfield) {
400 				fraglist[siz] += cnt;
401 				pos += siz;
402 				field <<= siz;
403 				subfield <<= siz;
404 			}
405 			field <<= 1;
406 			subfield <<= 1;
407 		}
408 	}
409 }
410 
411 /*
412  * block operations
413  *
414  * check if a block is available
415  */
416 int
417 ffs_isblock(struct fs *fs, unsigned char *cp, ufs1_daddr_t h)
418 {
419 	unsigned char mask;
420 
421 	switch ((int)fs->fs_frag) {
422 	case 8:
423 		return (cp[h] == 0xff);
424 	case 4:
425 		mask = 0x0f << ((h & 0x1) << 2);
426 		return ((cp[h >> 1] & mask) == mask);
427 	case 2:
428 		mask = 0x03 << ((h & 0x3) << 1);
429 		return ((cp[h >> 2] & mask) == mask);
430 	case 1:
431 		mask = 0x01 << (h & 0x7);
432 		return ((cp[h >> 3] & mask) == mask);
433 	default:
434 #ifdef _KERNEL
435 		panic("ffs_isblock");
436 #endif
437 		break;
438 	}
439 	return (0);
440 }
441 
442 /*
443  * check if a block is free
444  */
445 int
446 ffs_isfreeblock(struct fs *fs, u_char *cp, ufs1_daddr_t h)
447 {
448 
449 	switch ((int)fs->fs_frag) {
450 	case 8:
451 		return (cp[h] == 0);
452 	case 4:
453 		return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0);
454 	case 2:
455 		return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0);
456 	case 1:
457 		return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0);
458 	default:
459 #ifdef _KERNEL
460 		panic("ffs_isfreeblock");
461 #endif
462 		break;
463 	}
464 	return (0);
465 }
466 
467 /*
468  * take a block out of the map
469  */
470 void
471 ffs_clrblock(struct fs *fs, u_char *cp, ufs1_daddr_t h)
472 {
473 
474 	switch ((int)fs->fs_frag) {
475 	case 8:
476 		cp[h] = 0;
477 		return;
478 	case 4:
479 		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
480 		return;
481 	case 2:
482 		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
483 		return;
484 	case 1:
485 		cp[h >> 3] &= ~(0x01 << (h & 0x7));
486 		return;
487 	default:
488 #ifdef _KERNEL
489 		panic("ffs_clrblock");
490 #endif
491 		break;
492 	}
493 }
494 
495 /*
496  * put a block into the map
497  */
498 void
499 ffs_setblock(struct fs *fs, unsigned char *cp, ufs1_daddr_t h)
500 {
501 
502 	switch ((int)fs->fs_frag) {
503 
504 	case 8:
505 		cp[h] = 0xff;
506 		return;
507 	case 4:
508 		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
509 		return;
510 	case 2:
511 		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
512 		return;
513 	case 1:
514 		cp[h >> 3] |= (0x01 << (h & 0x7));
515 		return;
516 	default:
517 #ifdef _KERNEL
518 		panic("ffs_setblock");
519 #endif
520 		break;
521 	}
522 }
523 
524 /*
525  * Update the cluster map because of an allocation or free.
526  *
527  * Cnt == 1 means free; cnt == -1 means allocating.
528  */
529 void
530 ffs_clusteracct(struct fs *fs, struct cg *cgp, ufs1_daddr_t blkno, int cnt)
531 {
532 	int32_t *sump;
533 	int32_t *lp;
534 	u_char *freemapp, *mapp;
535 	int i, start, end, forw, back, map;
536 	u_int bit;
537 
538 	if (fs->fs_contigsumsize <= 0)
539 		return;
540 	freemapp = cg_clustersfree(cgp);
541 	sump = cg_clustersum(cgp);
542 	/*
543 	 * Allocate or clear the actual block.
544 	 */
545 	if (cnt > 0)
546 		setbit(freemapp, blkno);
547 	else
548 		clrbit(freemapp, blkno);
549 	/*
550 	 * Find the size of the cluster going forward.
551 	 */
552 	start = blkno + 1;
553 	end = start + fs->fs_contigsumsize;
554 	if (end >= cgp->cg_nclusterblks)
555 		end = cgp->cg_nclusterblks;
556 	mapp = &freemapp[start / NBBY];
557 	map = *mapp++;
558 	bit = 1U << (start % NBBY);
559 	for (i = start; i < end; i++) {
560 		if ((map & bit) == 0)
561 			break;
562 		if ((i & (NBBY - 1)) != (NBBY - 1)) {
563 			bit <<= 1;
564 		} else {
565 			map = *mapp++;
566 			bit = 1;
567 		}
568 	}
569 	forw = i - start;
570 	/*
571 	 * Find the size of the cluster going backward.
572 	 */
573 	start = blkno - 1;
574 	end = start - fs->fs_contigsumsize;
575 	if (end < 0)
576 		end = -1;
577 	mapp = &freemapp[start / NBBY];
578 	map = *mapp--;
579 	bit = 1U << (start % NBBY);
580 	for (i = start; i > end; i--) {
581 		if ((map & bit) == 0)
582 			break;
583 		if ((i & (NBBY - 1)) != 0) {
584 			bit >>= 1;
585 		} else {
586 			map = *mapp--;
587 			bit = 1U << (NBBY - 1);
588 		}
589 	}
590 	back = start - i;
591 	/*
592 	 * Account for old cluster and the possibly new forward and
593 	 * back clusters.
594 	 */
595 	i = back + forw + 1;
596 	if (i > fs->fs_contigsumsize)
597 		i = fs->fs_contigsumsize;
598 	sump[i] += cnt;
599 	if (back > 0)
600 		sump[back] -= cnt;
601 	if (forw > 0)
602 		sump[forw] -= cnt;
603 	/*
604 	 * Update cluster summary information.
605 	 */
606 	lp = &sump[fs->fs_contigsumsize];
607 	for (i = fs->fs_contigsumsize; i > 0; i--)
608 		if (*lp-- > 0)
609 			break;
610 	fs->fs_maxcluster[cgp->cg_cgx] = i;
611 }
612