ffs_subr.c revision 1.18
1 /* $NetBSD: ffs_subr.c,v 1.18 2001/10/26 06:37:55 lukem 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 8.5 (Berkeley) 3/21/95 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #ifndef _KERNEL 41 #include <ufs/ufs/dinode.h> 42 #include <ufs/ffs/fs.h> 43 #include <ufs/ffs/ffs_extern.h> 44 #include <ufs/ufs/ufs_bswap.h> 45 #endif 46 47 /* in ffs_tables.c */ 48 extern int inside[], around[]; 49 extern u_char *fragtbl[]; 50 51 #ifdef _KERNEL 52 #include <sys/vnode.h> 53 #include <sys/mount.h> 54 #include <sys/buf.h> 55 #include <ufs/ufs/inode.h> 56 #include <ufs/ufs/ufsmount.h> 57 #include <ufs/ufs/ufs_extern.h> 58 #include <ufs/ffs/fs.h> 59 #include <ufs/ffs/ffs_extern.h> 60 #include <ufs/ufs/ufs_bswap.h> 61 62 /* 63 * Return buffer with the contents of block "offset" from the beginning of 64 * directory "ip". If "res" is non-zero, fill it in with a pointer to the 65 * remaining space in the directory. 66 */ 67 int 68 ffs_blkatoff(v) 69 void *v; 70 { 71 struct vop_blkatoff_args /* { 72 struct vnode *a_vp; 73 off_t a_offset; 74 char **a_res; 75 struct buf **a_bpp; 76 } */ *ap = v; 77 struct inode *ip; 78 struct fs *fs; 79 struct buf *bp; 80 ufs_daddr_t lbn; 81 int bsize, error; 82 83 ip = VTOI(ap->a_vp); 84 fs = ip->i_fs; 85 lbn = lblkno(fs, ap->a_offset); 86 bsize = blksize(fs, ip, lbn); 87 88 *ap->a_bpp = NULL; 89 if ((error = bread(ap->a_vp, lbn, bsize, NOCRED, &bp)) != 0) { 90 brelse(bp); 91 return (error); 92 } 93 if (ap->a_res) 94 *ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset); 95 *ap->a_bpp = bp; 96 return (0); 97 } 98 #endif 99 100 /* 101 * Update the frsum fields to reflect addition or deletion 102 * of some frags. 103 */ 104 void 105 ffs_fragacct(fs, fragmap, fraglist, cnt, needswap) 106 struct fs *fs; 107 int fragmap; 108 int32_t fraglist[]; 109 int cnt; 110 int needswap; 111 { 112 int inblk; 113 int field, subfield; 114 int siz, pos; 115 116 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 117 fragmap <<= 1; 118 for (siz = 1; siz < fs->fs_frag; siz++) { 119 if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0) 120 continue; 121 field = around[siz]; 122 subfield = inside[siz]; 123 for (pos = siz; pos <= fs->fs_frag; pos++) { 124 if ((fragmap & field) == subfield) { 125 fraglist[siz] = ufs_rw32( 126 ufs_rw32(fraglist[siz], needswap) + cnt, 127 needswap); 128 pos += siz; 129 field <<= siz; 130 subfield <<= siz; 131 } 132 field <<= 1; 133 subfield <<= 1; 134 } 135 } 136 } 137 138 #if defined(_KERNEL) && defined(DIAGNOSTIC) 139 void 140 ffs_checkoverlap(bp, ip) 141 struct buf *bp; 142 struct inode *ip; 143 { 144 struct buf *ebp, *ep; 145 ufs_daddr_t start, last; 146 struct vnode *vp; 147 148 ebp = &buf[nbuf]; 149 start = bp->b_blkno; 150 last = start + btodb(bp->b_bcount) - 1; 151 for (ep = buf; ep < ebp; ep++) { 152 if (ep == bp || (ep->b_flags & B_INVAL) || 153 ep->b_vp == NULLVP) 154 continue; 155 if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0, NULL)) 156 continue; 157 if (vp != ip->i_devvp) 158 continue; 159 /* look for overlap */ 160 if (ep->b_bcount == 0 || ep->b_blkno > last || 161 ep->b_blkno + btodb(ep->b_bcount) <= start) 162 continue; 163 vprint("Disk overlap", vp); 164 printf("\tstart %d, end %d overlap start %d, end %ld\n", 165 start, last, ep->b_blkno, 166 ep->b_blkno + btodb(ep->b_bcount) - 1); 167 panic("Disk buffer overlap"); 168 } 169 } 170 #endif /* DIAGNOSTIC */ 171 172 /* 173 * block operations 174 * 175 * check if a block is available 176 */ 177 int 178 ffs_isblock(fs, cp, h) 179 struct fs *fs; 180 u_char *cp; 181 ufs_daddr_t h; 182 { 183 u_char mask; 184 185 switch ((int)fs->fs_frag) { 186 case 8: 187 return (cp[h] == 0xff); 188 case 4: 189 mask = 0x0f << ((h & 0x1) << 2); 190 return ((cp[h >> 1] & mask) == mask); 191 case 2: 192 mask = 0x03 << ((h & 0x3) << 1); 193 return ((cp[h >> 2] & mask) == mask); 194 case 1: 195 mask = 0x01 << (h & 0x7); 196 return ((cp[h >> 3] & mask) == mask); 197 default: 198 panic("ffs_isblock: unknown fs_frag %d", (int)fs->fs_frag); 199 } 200 } 201 202 /* 203 * check if a block is free 204 */ 205 int 206 ffs_isfreeblock(fs, cp, h) 207 struct fs *fs; 208 u_char *cp; 209 ufs_daddr_t h; 210 { 211 212 switch ((int)fs->fs_frag) { 213 case 8: 214 return (cp[h] == 0); 215 case 4: 216 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 217 case 2: 218 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 219 case 1: 220 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 221 default: 222 panic("ffs_isfreeblock: unknown fs_frag %d", (int)fs->fs_frag); 223 } 224 } 225 226 /* 227 * take a block out of the map 228 */ 229 void 230 ffs_clrblock(fs, cp, h) 231 struct fs *fs; 232 u_char *cp; 233 ufs_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 panic("ffs_clrblock: unknown fs_frag %d", (int)fs->fs_frag); 251 } 252 } 253 254 /* 255 * put a block into the map 256 */ 257 void 258 ffs_setblock(fs, cp, h) 259 struct fs *fs; 260 u_char *cp; 261 ufs_daddr_t h; 262 { 263 264 switch ((int)fs->fs_frag) { 265 266 case 8: 267 cp[h] = 0xff; 268 return; 269 case 4: 270 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 271 return; 272 case 2: 273 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 274 return; 275 case 1: 276 cp[h >> 3] |= (0x01 << (h & 0x7)); 277 return; 278 default: 279 panic("ffs_setblock: unknown fs_frag %d", (int)fs->fs_frag); 280 } 281 } 282
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