1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
|
/*-
* modified for Lites 1.1
*
* Aug 1995, Godmar Back (gback@cs.utah.edu)
* University of Utah, Department of Computer Science
*/
/*-
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ffs_subr.c 8.2 (Berkeley) 9/21/93
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/lock.h>
#include <sys/ucred.h>
#include <sys/vnode.h>
#include <fs/ext2fs/inode.h>
#include <fs/ext2fs/ext2_extern.h>
#include <fs/ext2fs/ext2fs.h>
#include <fs/ext2fs/fs.h>
#ifdef KDB
#include <fs/ext2fs/ext2_mount.h>
void ext2_checkoverlap(struct buf *, struct inode *);
#endif
/*
* Return buffer with the contents of block "offset" from the beginning of
* directory "ip". If "res" is non-zero, fill it in with a pointer to the
* remaining space in the directory.
*/
int
ext2_blkatoff(vp, offset, res, bpp)
struct vnode *vp;
off_t offset;
char **res;
struct buf **bpp;
{
struct inode *ip;
struct m_ext2fs *fs;
struct buf *bp;
int32_t lbn;
int bsize, error;
ip = VTOI(vp);
fs = ip->i_e2fs;
lbn = lblkno(fs, offset);
bsize = blksize(fs, ip, lbn);
*bpp = NULL;
if ((error = bread(vp, lbn, bsize, NOCRED, &bp)) != 0) {
brelse(bp);
return (error);
}
if (res)
*res = (char *)bp->b_data + blkoff(fs, offset);
*bpp = bp;
return (0);
}
#ifdef KDB
void
ext2_checkoverlap(bp, ip)
struct buf *bp;
struct inode *ip;
{
struct buf *ebp, *ep;
int32_t start, last;
struct vnode *vp;
ebp = &buf[nbuf];
start = bp->b_blkno;
last = start + btodb(bp->b_bcount) - 1;
for (ep = buf; ep < ebp; ep++) {
if (ep == bp || (ep->b_flags & B_INVAL))
continue;
vp = ip->i_ump->um_devvp;
/* look for overlap */
if (ep->b_bcount == 0 || ep->b_blkno > last ||
ep->b_blkno + btodb(ep->b_bcount) <= start)
continue;
vprint("Disk overlap", vp);
(void)printf("\tstart %d, end %d overlap start %lld, end %ld\n",
start, last, (long long)ep->b_blkno,
(long)(ep->b_blkno + btodb(ep->b_bcount) - 1));
panic("Disk buffer overlap");
}
}
#endif /* KDB */
/*
* Update the cluster map because of an allocation of free like ffs.
*
* Cnt == 1 means free; cnt == -1 means allocating.
*/
void
ext2_clusteracct(struct m_ext2fs *fs, char *bbp, int cg, daddr_t bno, int cnt)
{
int32_t *sump = fs->e2fs_clustersum[cg].cs_sum;
int32_t *lp;
int back, bit, end, forw, i, loc, start;
/* Initialize the cluster summary array. */
if (fs->e2fs_clustersum[cg].cs_init == 0) {
int run = 0;
bit = 1;
loc = 0;
for (i = 0; i < fs->e2fs->e2fs_fpg; i++) {
if ((bbp[loc] & bit) == 0)
run++;
else if (run != 0) {
if (run > fs->e2fs_contigsumsize)
run = fs->e2fs_contigsumsize;
sump[run]++;
run = 0;
}
if ((i & (NBBY - 1)) != (NBBY - 1))
bit <<= 1;
else {
loc++;
bit = 1;
}
}
if (run != 0) {
if (run > fs->e2fs_contigsumsize)
run = fs->e2fs_contigsumsize;
sump[run]++;
}
fs->e2fs_clustersum[cg].cs_init = 1;
}
if (fs->e2fs_contigsumsize <= 0)
return;
/* Find the size of the cluster going forward. */
start = bno + 1;
end = start + fs->e2fs_contigsumsize;
if (end > fs->e2fs->e2fs_fpg)
end = fs->e2fs->e2fs_fpg;
loc = start / NBBY;
bit = 1 << (start % NBBY);
for (i = start; i < end; i++) {
if ((bbp[loc] & bit) != 0)
break;
if ((i & (NBBY - 1)) != (NBBY - 1))
bit <<= 1;
else {
loc++;
bit = 1;
}
}
forw = i - start;
/* Find the size of the cluster going backward. */
start = bno - 1;
end = start - fs->e2fs_contigsumsize;
if (end < 0)
end = -1;
loc = start / NBBY;
bit = 1 << (start % NBBY);
for (i = start; i > end; i--) {
if ((bbp[loc] & bit) != 0)
break;
if ((i & (NBBY - 1)) != 0)
bit >>= 1;
else {
loc--;
bit = 1 << (NBBY - 1);
}
}
back = start - i;
/*
* Account for old cluster and the possibly new forward and
* back clusters.
*/
i = back + forw + 1;
if (i > fs->e2fs_contigsumsize)
i = fs->e2fs_contigsumsize;
sump[i] += cnt;
if (back > 0)
sump[back] -= cnt;
if (forw > 0)
sump[forw] -= cnt;
/* Update cluster summary information. */
lp = &sump[fs->e2fs_contigsumsize];
for (i = fs->e2fs_contigsumsize; i > 0; i--)
if (*lp-- > 0)
break;
fs->e2fs_maxcluster[cg] = i;
}
|
