1 /* $NetBSD: ffs_subr.c,v 1.3 1994/10/20 04:20:58 cgd Exp $ */ 2 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)ffs_subr.c 8.2 (Berkeley) 9/21/93 36 */ 37 38 #include <sys/param.h> 39 #include <ufs/ffs/fs.h> 40 41 #ifdef KERNEL 42 #include <sys/systm.h> 43 #include <sys/vnode.h> 44 #include <ufs/ffs/ffs_extern.h> 45 #include <sys/buf.h> 46 #include <ufs/ufs/quota.h> 47 #include <ufs/ufs/inode.h> 48 49 /* 50 * Return buffer with the contents of block "offset" from the beginning of 51 * directory "ip". If "res" is non-zero, fill it in with a pointer to the 52 * remaining space in the directory. 53 */ 54 int 55 ffs_blkatoff(ap) 56 struct vop_blkatoff_args /* { 57 struct vnode *a_vp; 58 off_t a_offset; 59 char **a_res; 60 struct buf **a_bpp; 61 } */ *ap; 62 { 63 struct inode *ip; 64 register struct fs *fs; 65 struct buf *bp; 66 daddr_t lbn; 67 int bsize, error; 68 69 ip = VTOI(ap->a_vp); 70 fs = ip->i_fs; 71 lbn = lblkno(fs, ap->a_offset); 72 bsize = blksize(fs, ip, lbn); 73 74 *ap->a_bpp = NULL; 75 if (error = bread(ap->a_vp, lbn, bsize, NOCRED, &bp)) { 76 brelse(bp); 77 return (error); 78 } 79 if (ap->a_res) 80 *ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset); 81 *ap->a_bpp = bp; 82 return (0); 83 } 84 #endif 85 86 /* 87 * Update the frsum fields to reflect addition or deletion 88 * of some frags. 89 */ 90 void 91 ffs_fragacct(fs, fragmap, fraglist, cnt) 92 struct fs *fs; 93 int fragmap; 94 int32_t fraglist[]; 95 int cnt; 96 { 97 int inblk; 98 register int field, subfield; 99 register int siz, pos; 100 101 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 102 fragmap <<= 1; 103 for (siz = 1; siz < fs->fs_frag; siz++) { 104 if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0) 105 continue; 106 field = around[siz]; 107 subfield = inside[siz]; 108 for (pos = siz; pos <= fs->fs_frag; pos++) { 109 if ((fragmap & field) == subfield) { 110 fraglist[siz] += cnt; 111 pos += siz; 112 field <<= siz; 113 subfield <<= siz; 114 } 115 field <<= 1; 116 subfield <<= 1; 117 } 118 } 119 } 120 121 #if defined(KERNEL) && defined(DIAGNOSTIC) 122 void 123 ffs_checkoverlap(bp, ip) 124 struct buf *bp; 125 struct inode *ip; 126 { 127 register struct buf *ebp, *ep; 128 register daddr_t start, last; 129 struct vnode *vp; 130 131 ebp = &buf[nbuf]; 132 start = bp->b_blkno; 133 last = start + btodb(bp->b_bcount) - 1; 134 for (ep = buf; ep < ebp; ep++) { 135 if (ep == bp || (ep->b_flags & B_INVAL) || 136 ep->b_vp == NULLVP) 137 continue; 138 if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0, NULL)) 139 continue; 140 if (vp != ip->i_devvp) 141 continue; 142 /* look for overlap */ 143 if (ep->b_bcount == 0 || ep->b_blkno > last || 144 ep->b_blkno + btodb(ep->b_bcount) <= start) 145 continue; 146 vprint("Disk overlap", vp); 147 (void)printf("\tstart %d, end %d overlap start %d, end %d\n", 148 start, last, ep->b_blkno, 149 ep->b_blkno + btodb(ep->b_bcount) - 1); 150 panic("Disk buffer overlap"); 151 } 152 } 153 #endif /* DIAGNOSTIC */ 154 155 /* 156 * block operations 157 * 158 * check if a block is available 159 */ 160 int 161 ffs_isblock(fs, cp, h) 162 struct fs *fs; 163 unsigned char *cp; 164 daddr_t h; 165 { 166 unsigned char mask; 167 168 switch ((int)fs->fs_frag) { 169 case 8: 170 return (cp[h] == 0xff); 171 case 4: 172 mask = 0x0f << ((h & 0x1) << 2); 173 return ((cp[h >> 1] & mask) == mask); 174 case 2: 175 mask = 0x03 << ((h & 0x3) << 1); 176 return ((cp[h >> 2] & mask) == mask); 177 case 1: 178 mask = 0x01 << (h & 0x7); 179 return ((cp[h >> 3] & mask) == mask); 180 default: 181 panic("ffs_isblock"); 182 } 183 } 184 185 /* 186 * take a block out of the map 187 */ 188 void 189 ffs_clrblock(fs, cp, h) 190 struct fs *fs; 191 u_char *cp; 192 daddr_t h; 193 { 194 195 switch ((int)fs->fs_frag) { 196 case 8: 197 cp[h] = 0; 198 return; 199 case 4: 200 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 201 return; 202 case 2: 203 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 204 return; 205 case 1: 206 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 207 return; 208 default: 209 panic("ffs_clrblock"); 210 } 211 } 212 213 /* 214 * put a block into the map 215 */ 216 void 217 ffs_setblock(fs, cp, h) 218 struct fs *fs; 219 unsigned char *cp; 220 daddr_t h; 221 { 222 223 switch ((int)fs->fs_frag) { 224 225 case 8: 226 cp[h] = 0xff; 227 return; 228 case 4: 229 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 230 return; 231 case 2: 232 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 233 return; 234 case 1: 235 cp[h >> 3] |= (0x01 << (h & 0x7)); 236 return; 237 default: 238 panic("ffs_setblock"); 239 } 240 } 241