ffs_subr.c revision 331722 
1/*-
2 * Copyright (c) 1982, 1986, 1989, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 *	@(#)ffs_subr.c	8.5 (Berkeley) 3/21/95
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD: stable/11/sys/ufs/ffs/ffs_subr.c 331722 2018-03-29 02:50:57Z eadler $");
34
35#include <sys/param.h>
36
37#ifndef _KERNEL
38#include <ufs/ufs/dinode.h>
39#include <ufs/ffs/fs.h>
40#else
41#include <sys/systm.h>
42#include <sys/lock.h>
43#include <sys/malloc.h>
44#include <sys/mount.h>
45#include <sys/vnode.h>
46#include <sys/bio.h>
47#include <sys/buf.h>
48#include <sys/ucred.h>
49
50#include <ufs/ufs/quota.h>
51#include <ufs/ufs/inode.h>
52#include <ufs/ufs/extattr.h>
53#include <ufs/ufs/ufsmount.h>
54#include <ufs/ufs/ufs_extern.h>
55#include <ufs/ffs/ffs_extern.h>
56#include <ufs/ffs/fs.h>
57
58/*
59 * Return buffer with the contents of block "offset" from the beginning of
60 * directory "ip".  If "res" is non-zero, fill it in with a pointer to the
61 * remaining space in the directory.
62 */
63int
64ffs_blkatoff(vp, offset, res, bpp)
65	struct vnode *vp;
66	off_t offset;
67	char **res;
68	struct buf **bpp;
69{
70	struct inode *ip;
71	struct fs *fs;
72	struct buf *bp;
73	ufs_lbn_t lbn;
74	int bsize, error;
75
76	ip = VTOI(vp);
77	fs = ITOFS(ip);
78	lbn = lblkno(fs, offset);
79	bsize = blksize(fs, ip, lbn);
80
81	*bpp = NULL;
82	error = bread(vp, lbn, bsize, NOCRED, &bp);
83	if (error) {
84		brelse(bp);
85		return (error);
86	}
87	if (res)
88		*res = (char *)bp->b_data + blkoff(fs, offset);
89	*bpp = bp;
90	return (0);
91}
92
93/*
94 * Load up the contents of an inode and copy the appropriate pieces
95 * to the incore copy.
96 */
97void
98ffs_load_inode(bp, ip, fs, ino)
99	struct buf *bp;
100	struct inode *ip;
101	struct fs *fs;
102	ino_t ino;
103{
104
105	if (I_IS_UFS1(ip)) {
106		*ip->i_din1 =
107		    *((struct ufs1_dinode *)bp->b_data + ino_to_fsbo(fs, ino));
108		ip->i_mode = ip->i_din1->di_mode;
109		ip->i_nlink = ip->i_din1->di_nlink;
110		ip->i_size = ip->i_din1->di_size;
111		ip->i_flags = ip->i_din1->di_flags;
112		ip->i_gen = ip->i_din1->di_gen;
113		ip->i_uid = ip->i_din1->di_uid;
114		ip->i_gid = ip->i_din1->di_gid;
115	} else {
116		*ip->i_din2 =
117		    *((struct ufs2_dinode *)bp->b_data + ino_to_fsbo(fs, ino));
118		ip->i_mode = ip->i_din2->di_mode;
119		ip->i_nlink = ip->i_din2->di_nlink;
120		ip->i_size = ip->i_din2->di_size;
121		ip->i_flags = ip->i_din2->di_flags;
122		ip->i_gen = ip->i_din2->di_gen;
123		ip->i_uid = ip->i_din2->di_uid;
124		ip->i_gid = ip->i_din2->di_gid;
125	}
126}
127#endif /* KERNEL */
128
129/*
130 * Update the frsum fields to reflect addition or deletion
131 * of some frags.
132 */
133void
134ffs_fragacct(fs, fragmap, fraglist, cnt)
135	struct fs *fs;
136	int fragmap;
137	int32_t fraglist[];
138	int cnt;
139{
140	int inblk;
141	int field, subfield;
142	int siz, pos;
143
144	inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1;
145	fragmap <<= 1;
146	for (siz = 1; siz < fs->fs_frag; siz++) {
147		if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0)
148			continue;
149		field = around[siz];
150		subfield = inside[siz];
151		for (pos = siz; pos <= fs->fs_frag; pos++) {
152			if ((fragmap & field) == subfield) {
153				fraglist[siz] += cnt;
154				pos += siz;
155				field <<= siz;
156				subfield <<= siz;
157			}
158			field <<= 1;
159			subfield <<= 1;
160		}
161	}
162}
163
164/*
165 * block operations
166 *
167 * check if a block is available
168 */
169int
170ffs_isblock(fs, cp, h)
171	struct fs *fs;
172	unsigned char *cp;
173	ufs1_daddr_t h;
174{
175	unsigned char mask;
176
177	switch ((int)fs->fs_frag) {
178	case 8:
179		return (cp[h] == 0xff);
180	case 4:
181		mask = 0x0f << ((h & 0x1) << 2);
182		return ((cp[h >> 1] & mask) == mask);
183	case 2:
184		mask = 0x03 << ((h & 0x3) << 1);
185		return ((cp[h >> 2] & mask) == mask);
186	case 1:
187		mask = 0x01 << (h & 0x7);
188		return ((cp[h >> 3] & mask) == mask);
189	default:
190#ifdef _KERNEL
191		panic("ffs_isblock");
192#endif
193		break;
194	}
195	return (0);
196}
197
198/*
199 * check if a block is free
200 */
201int
202ffs_isfreeblock(fs, cp, h)
203	struct fs *fs;
204	u_char *cp;
205	ufs1_daddr_t h;
206{
207
208	switch ((int)fs->fs_frag) {
209	case 8:
210		return (cp[h] == 0);
211	case 4:
212		return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0);
213	case 2:
214		return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0);
215	case 1:
216		return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0);
217	default:
218#ifdef _KERNEL
219		panic("ffs_isfreeblock");
220#endif
221		break;
222	}
223	return (0);
224}
225
226/*
227 * take a block out of the map
228 */
229void
230ffs_clrblock(fs, cp, h)
231	struct fs *fs;
232	u_char *cp;
233	ufs1_daddr_t h;
234{
235
236	switch ((int)fs->fs_frag) {
237	case 8:
238		cp[h] = 0;
239		return;
240	case 4:
241		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
242		return;
243	case 2:
244		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
245		return;
246	case 1:
247		cp[h >> 3] &= ~(0x01 << (h & 0x7));
248		return;
249	default:
250#ifdef _KERNEL
251		panic("ffs_clrblock");
252#endif
253		break;
254	}
255}
256
257/*
258 * put a block into the map
259 */
260void
261ffs_setblock(fs, cp, h)
262	struct fs *fs;
263	unsigned char *cp;
264	ufs1_daddr_t h;
265{
266
267	switch ((int)fs->fs_frag) {
268
269	case 8:
270		cp[h] = 0xff;
271		return;
272	case 4:
273		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
274		return;
275	case 2:
276		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
277		return;
278	case 1:
279		cp[h >> 3] |= (0x01 << (h & 0x7));
280		return;
281	default:
282#ifdef _KERNEL
283		panic("ffs_setblock");
284#endif
285		break;
286	}
287}
288
289/*
290 * Update the cluster map because of an allocation or free.
291 *
292 * Cnt == 1 means free; cnt == -1 means allocating.
293 */
294void
295ffs_clusteracct(fs, cgp, blkno, cnt)
296	struct fs *fs;
297	struct cg *cgp;
298	ufs1_daddr_t blkno;
299	int cnt;
300{
301	int32_t *sump;
302	int32_t *lp;
303	u_char *freemapp, *mapp;
304	int i, start, end, forw, back, map, bit;
305
306	if (fs->fs_contigsumsize <= 0)
307		return;
308	freemapp = cg_clustersfree(cgp);
309	sump = cg_clustersum(cgp);
310	/*
311	 * Allocate or clear the actual block.
312	 */
313	if (cnt > 0)
314		setbit(freemapp, blkno);
315	else
316		clrbit(freemapp, blkno);
317	/*
318	 * Find the size of the cluster going forward.
319	 */
320	start = blkno + 1;
321	end = start + fs->fs_contigsumsize;
322	if (end >= cgp->cg_nclusterblks)
323		end = cgp->cg_nclusterblks;
324	mapp = &freemapp[start / NBBY];
325	map = *mapp++;
326	bit = 1 << (start % NBBY);
327	for (i = start; i < end; i++) {
328		if ((map & bit) == 0)
329			break;
330		if ((i & (NBBY - 1)) != (NBBY - 1)) {
331			bit <<= 1;
332		} else {
333			map = *mapp++;
334			bit = 1;
335		}
336	}
337	forw = i - start;
338	/*
339	 * Find the size of the cluster going backward.
340	 */
341	start = blkno - 1;
342	end = start - fs->fs_contigsumsize;
343	if (end < 0)
344		end = -1;
345	mapp = &freemapp[start / NBBY];
346	map = *mapp--;
347	bit = 1 << (start % NBBY);
348	for (i = start; i > end; i--) {
349		if ((map & bit) == 0)
350			break;
351		if ((i & (NBBY - 1)) != 0) {
352			bit >>= 1;
353		} else {
354			map = *mapp--;
355			bit = 1 << (NBBY - 1);
356		}
357	}
358	back = start - i;
359	/*
360	 * Account for old cluster and the possibly new forward and
361	 * back clusters.
362	 */
363	i = back + forw + 1;
364	if (i > fs->fs_contigsumsize)
365		i = fs->fs_contigsumsize;
366	sump[i] += cnt;
367	if (back > 0)
368		sump[back] -= cnt;
369	if (forw > 0)
370		sump[forw] -= cnt;
371	/*
372	 * Update cluster summary information.
373	 */
374	lp = &sump[fs->fs_contigsumsize];
375	for (i = fs->fs_contigsumsize; i > 0; i--)
376		if (*lp-- > 0)
377			break;
378	fs->fs_maxcluster[cgp->cg_cgx] = i;
379}
380