ffs_subr.c revision 1.23
1 /* $NetBSD: ffs_subr.c,v 1.23 2002/07/06 15:39:07 fredette 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/cdefs.h> 39 #if defined(__KERNEL_RCSID) 40 __KERNEL_RCSID(0, "$NetBSD: ffs_subr.c,v 1.23 2002/07/06 15:39:07 fredette Exp $"); 41 #endif 42 43 #if HAVE_CONFIG_H 44 #include "config.h" 45 #endif 46 47 #include <sys/param.h> 48 49 /* in ffs_tables.c */ 50 extern int inside[], around[]; 51 extern u_char *fragtbl[]; 52 53 #ifndef _KERNEL 54 #include <ufs/ufs/dinode.h> 55 #include <ufs/ffs/fs.h> 56 #include <ufs/ffs/ffs_extern.h> 57 #include <ufs/ufs/ufs_bswap.h> 58 void panic __P((const char *, ...)) 59 __attribute__((__noreturn__,__format__(__printf__,1,2))); 60 61 #else /* _KERNEL */ 62 #include <sys/systm.h> 63 #include <sys/vnode.h> 64 #include <sys/mount.h> 65 #include <sys/buf.h> 66 #include <ufs/ufs/inode.h> 67 #include <ufs/ufs/ufsmount.h> 68 #include <ufs/ufs/ufs_extern.h> 69 #include <ufs/ffs/fs.h> 70 #include <ufs/ffs/ffs_extern.h> 71 #include <ufs/ufs/ufs_bswap.h> 72 73 /* 74 * Return buffer with the contents of block "offset" from the beginning of 75 * directory "ip". If "res" is non-zero, fill it in with a pointer to the 76 * remaining space in the directory. 77 */ 78 int 79 ffs_blkatoff(v) 80 void *v; 81 { 82 struct vop_blkatoff_args /* { 83 struct vnode *a_vp; 84 off_t a_offset; 85 char **a_res; 86 struct buf **a_bpp; 87 } */ *ap = v; 88 struct inode *ip; 89 struct fs *fs; 90 struct buf *bp; 91 ufs_daddr_t lbn; 92 int bsize, error; 93 94 ip = VTOI(ap->a_vp); 95 fs = ip->i_fs; 96 lbn = lblkno(fs, ap->a_offset); 97 bsize = blksize(fs, ip, lbn); 98 99 *ap->a_bpp = NULL; 100 if ((error = bread(ap->a_vp, lbn, bsize, NOCRED, &bp)) != 0) { 101 brelse(bp); 102 return (error); 103 } 104 if (ap->a_res) 105 *ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset); 106 *ap->a_bpp = bp; 107 return (0); 108 } 109 #endif /* _KERNEL */ 110 111 /* 112 * Update the frsum fields to reflect addition or deletion 113 * of some frags. 114 */ 115 void 116 ffs_fragacct(fs, fragmap, fraglist, cnt, needswap) 117 struct fs *fs; 118 int fragmap; 119 int32_t fraglist[]; 120 int cnt; 121 int needswap; 122 { 123 int inblk; 124 int field, subfield; 125 int siz, pos; 126 127 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 128 fragmap <<= 1; 129 for (siz = 1; siz < fs->fs_frag; siz++) { 130 if ((inblk & (1 << (siz + (fs->fs_frag & (NBBY - 1))))) == 0) 131 continue; 132 field = around[siz]; 133 subfield = inside[siz]; 134 for (pos = siz; pos <= fs->fs_frag; pos++) { 135 if ((fragmap & field) == subfield) { 136 fraglist[siz] = ufs_rw32( 137 ufs_rw32(fraglist[siz], needswap) + cnt, 138 needswap); 139 pos += siz; 140 field <<= siz; 141 subfield <<= siz; 142 } 143 field <<= 1; 144 subfield <<= 1; 145 } 146 } 147 } 148 149 #if defined(_KERNEL) && defined(DIAGNOSTIC) 150 void 151 ffs_checkoverlap(bp, ip) 152 struct buf *bp; 153 struct inode *ip; 154 { 155 struct buf *ebp, *ep; 156 ufs_daddr_t start, last; 157 struct vnode *vp; 158 159 ebp = &buf[nbuf]; 160 start = bp->b_blkno; 161 last = start + btodb(bp->b_bcount) - 1; 162 for (ep = buf; ep < ebp; ep++) { 163 if (ep == bp || (ep->b_flags & B_INVAL) || 164 ep->b_vp == NULLVP) 165 continue; 166 if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0, NULL)) 167 continue; 168 if (vp != ip->i_devvp) 169 continue; 170 /* look for overlap */ 171 if (ep->b_bcount == 0 || ep->b_blkno > last || 172 ep->b_blkno + btodb(ep->b_bcount) <= start) 173 continue; 174 vprint("Disk overlap", vp); 175 printf("\tstart %d, end %d overlap start %d, end %ld\n", 176 start, last, ep->b_blkno, 177 (long) ep->b_blkno + btodb(ep->b_bcount) - 1); 178 panic("Disk buffer overlap"); 179 } 180 } 181 #endif /* _KERNEL && DIAGNOSTIC */ 182 183 /* 184 * block operations 185 * 186 * check if a block is available 187 */ 188 int 189 ffs_isblock(fs, cp, h) 190 struct fs *fs; 191 u_char *cp; 192 ufs_daddr_t h; 193 { 194 u_char mask; 195 196 switch ((int)fs->fs_fragshift) { 197 case 3: 198 return (cp[h] == 0xff); 199 case 2: 200 mask = 0x0f << ((h & 0x1) << 2); 201 return ((cp[h >> 1] & mask) == mask); 202 case 1: 203 mask = 0x03 << ((h & 0x3) << 1); 204 return ((cp[h >> 2] & mask) == mask); 205 case 0: 206 mask = 0x01 << (h & 0x7); 207 return ((cp[h >> 3] & mask) == mask); 208 default: 209 panic("ffs_isblock: unknown fs_fragshift %d", 210 (int)fs->fs_fragshift); 211 } 212 } 213 214 /* 215 * check if a block is free 216 */ 217 int 218 ffs_isfreeblock(fs, cp, h) 219 struct fs *fs; 220 u_char *cp; 221 ufs_daddr_t h; 222 { 223 224 switch ((int)fs->fs_fragshift) { 225 case 3: 226 return (cp[h] == 0); 227 case 2: 228 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 229 case 1: 230 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 231 case 0: 232 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 233 default: 234 panic("ffs_isfreeblock: unknown fs_fragshift %d", 235 (int)fs->fs_fragshift); 236 } 237 } 238 239 /* 240 * take a block out of the map 241 */ 242 void 243 ffs_clrblock(fs, cp, h) 244 struct fs *fs; 245 u_char *cp; 246 ufs_daddr_t h; 247 { 248 249 switch ((int)fs->fs_fragshift) { 250 case 3: 251 cp[h] = 0; 252 return; 253 case 2: 254 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 255 return; 256 case 1: 257 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 258 return; 259 case 0: 260 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 261 return; 262 default: 263 panic("ffs_clrblock: unknown fs_fragshift %d", 264 (int)fs->fs_fragshift); 265 } 266 } 267 268 /* 269 * put a block into the map 270 */ 271 void 272 ffs_setblock(fs, cp, h) 273 struct fs *fs; 274 u_char *cp; 275 ufs_daddr_t h; 276 { 277 278 switch ((int)fs->fs_fragshift) { 279 case 3: 280 cp[h] = 0xff; 281 return; 282 case 2: 283 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 284 return; 285 case 1: 286 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 287 return; 288 case 0: 289 cp[h >> 3] |= (0x01 << (h & 0x7)); 290 return; 291 default: 292 panic("ffs_setblock: unknown fs_fragshift %d", 293 (int)fs->fs_fragshift); 294 } 295 } 296
Indexes created Tue Sep 30 20:09:53 GMT 2025