ffs_subr.c revision 1.20
1 /* $NetBSD: ffs_subr.c,v 1.20 2002/01/09 23:51:00 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/cdefs.h> 39 __KERNEL_RCSID(0, "$NetBSD: ffs_subr.c,v 1.20 2002/01/09 23:51:00 lukem Exp $"); 40 41 #include <sys/param.h> 42 43 /* in ffs_tables.c */ 44 extern int inside[], around[]; 45 extern u_char *fragtbl[]; 46 47 #ifndef _KERNEL 48 #include <ufs/ufs/dinode.h> 49 #include <ufs/ffs/fs.h> 50 #include <ufs/ffs/ffs_extern.h> 51 #include <ufs/ufs/ufs_bswap.h> 52 void panic __P((const char *, ...)) 53 __attribute__((__noreturn__,__format__(__printf__,1,2))); 54 55 #else /* _KERNEL */ 56 #include <sys/systm.h> 57 #include <sys/vnode.h> 58 #include <sys/mount.h> 59 #include <sys/buf.h> 60 #include <ufs/ufs/inode.h> 61 #include <ufs/ufs/ufsmount.h> 62 #include <ufs/ufs/ufs_extern.h> 63 #include <ufs/ffs/fs.h> 64 #include <ufs/ffs/ffs_extern.h> 65 #include <ufs/ufs/ufs_bswap.h> 66 67 /* 68 * Return buffer with the contents of block "offset" from the beginning of 69 * directory "ip". If "res" is non-zero, fill it in with a pointer to the 70 * remaining space in the directory. 71 */ 72 int 73 ffs_blkatoff(v) 74 void *v; 75 { 76 struct vop_blkatoff_args /* { 77 struct vnode *a_vp; 78 off_t a_offset; 79 char **a_res; 80 struct buf **a_bpp; 81 } */ *ap = v; 82 struct inode *ip; 83 struct fs *fs; 84 struct buf *bp; 85 ufs_daddr_t lbn; 86 int bsize, error; 87 88 ip = VTOI(ap->a_vp); 89 fs = ip->i_fs; 90 lbn = lblkno(fs, ap->a_offset); 91 bsize = blksize(fs, ip, lbn); 92 93 *ap->a_bpp = NULL; 94 if ((error = bread(ap->a_vp, lbn, bsize, NOCRED, &bp)) != 0) { 95 brelse(bp); 96 return (error); 97 } 98 if (ap->a_res) 99 *ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset); 100 *ap->a_bpp = bp; 101 return (0); 102 } 103 #endif /* _KERNEL */ 104 105 /* 106 * Update the frsum fields to reflect addition or deletion 107 * of some frags. 108 */ 109 void 110 ffs_fragacct(fs, fragmap, fraglist, cnt, needswap) 111 struct fs *fs; 112 int fragmap; 113 int32_t fraglist[]; 114 int cnt; 115 int needswap; 116 { 117 int inblk; 118 int field, subfield; 119 int siz, pos; 120 121 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 122 fragmap <<= 1; 123 for (siz = 1; siz < fs->fs_frag; siz++) { 124 if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0) 125 continue; 126 field = around[siz]; 127 subfield = inside[siz]; 128 for (pos = siz; pos <= fs->fs_frag; pos++) { 129 if ((fragmap & field) == subfield) { 130 fraglist[siz] = ufs_rw32( 131 ufs_rw32(fraglist[siz], needswap) + cnt, 132 needswap); 133 pos += siz; 134 field <<= siz; 135 subfield <<= siz; 136 } 137 field <<= 1; 138 subfield <<= 1; 139 } 140 } 141 } 142 143 #if defined(_KERNEL) && defined(DIAGNOSTIC) 144 void 145 ffs_checkoverlap(bp, ip) 146 struct buf *bp; 147 struct inode *ip; 148 { 149 struct buf *ebp, *ep; 150 ufs_daddr_t start, last; 151 struct vnode *vp; 152 153 ebp = &buf[nbuf]; 154 start = bp->b_blkno; 155 last = start + btodb(bp->b_bcount) - 1; 156 for (ep = buf; ep < ebp; ep++) { 157 if (ep == bp || (ep->b_flags & B_INVAL) || 158 ep->b_vp == NULLVP) 159 continue; 160 if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0, NULL)) 161 continue; 162 if (vp != ip->i_devvp) 163 continue; 164 /* look for overlap */ 165 if (ep->b_bcount == 0 || ep->b_blkno > last || 166 ep->b_blkno + btodb(ep->b_bcount) <= start) 167 continue; 168 vprint("Disk overlap", vp); 169 printf("\tstart %d, end %d overlap start %d, end %ld\n", 170 start, last, ep->b_blkno, 171 ep->b_blkno + btodb(ep->b_bcount) - 1); 172 panic("Disk buffer overlap"); 173 } 174 } 175 #endif /* _KERNEL && DIAGNOSTIC */ 176 177 /* 178 * block operations 179 * 180 * check if a block is available 181 */ 182 int 183 ffs_isblock(fs, cp, h) 184 struct fs *fs; 185 u_char *cp; 186 ufs_daddr_t h; 187 { 188 u_char mask; 189 190 switch ((int)fs->fs_frag) { 191 case 8: 192 return (cp[h] == 0xff); 193 case 4: 194 mask = 0x0f << ((h & 0x1) << 2); 195 return ((cp[h >> 1] & mask) == mask); 196 case 2: 197 mask = 0x03 << ((h & 0x3) << 1); 198 return ((cp[h >> 2] & mask) == mask); 199 case 1: 200 mask = 0x01 << (h & 0x7); 201 return ((cp[h >> 3] & mask) == mask); 202 default: 203 panic("ffs_isblock: unknown fs_frag %d", (int)fs->fs_frag); 204 } 205 } 206 207 /* 208 * check if a block is free 209 */ 210 int 211 ffs_isfreeblock(fs, cp, h) 212 struct fs *fs; 213 u_char *cp; 214 ufs_daddr_t h; 215 { 216 217 switch ((int)fs->fs_frag) { 218 case 8: 219 return (cp[h] == 0); 220 case 4: 221 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 222 case 2: 223 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 224 case 1: 225 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 226 default: 227 panic("ffs_isfreeblock: unknown fs_frag %d", (int)fs->fs_frag); 228 } 229 } 230 231 /* 232 * take a block out of the map 233 */ 234 void 235 ffs_clrblock(fs, cp, h) 236 struct fs *fs; 237 u_char *cp; 238 ufs_daddr_t h; 239 { 240 241 switch ((int)fs->fs_frag) { 242 case 8: 243 cp[h] = 0; 244 return; 245 case 4: 246 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 247 return; 248 case 2: 249 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 250 return; 251 case 1: 252 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 253 return; 254 default: 255 panic("ffs_clrblock: unknown fs_frag %d", (int)fs->fs_frag); 256 } 257 } 258 259 /* 260 * put a block into the map 261 */ 262 void 263 ffs_setblock(fs, cp, h) 264 struct fs *fs; 265 u_char *cp; 266 ufs_daddr_t h; 267 { 268 269 switch ((int)fs->fs_frag) { 270 271 case 8: 272 cp[h] = 0xff; 273 return; 274 case 4: 275 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 276 return; 277 case 2: 278 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 279 return; 280 case 1: 281 cp[h >> 3] |= (0x01 << (h & 0x7)); 282 return; 283 default: 284 panic("ffs_setblock: unknown fs_frag %d", (int)fs->fs_frag); 285 } 286 } 287
Indexes created Tue Sep 30 17:09:57 GMT 2025