ffs_subr.c revision 1.19
1 /* $NetBSD: ffs_subr.c,v 1.19 2001/10/30 01:11:54 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 1.19 2001/10/30 01:11:54 lukem Exp $"); 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #ifndef _KERNEL 44 #include <ufs/ufs/dinode.h> 45 #include <ufs/ffs/fs.h> 46 #include <ufs/ffs/ffs_extern.h> 47 #include <ufs/ufs/ufs_bswap.h> 48 #endif 49 50 /* in ffs_tables.c */ 51 extern int inside[], around[]; 52 extern u_char *fragtbl[]; 53 54 #ifdef _KERNEL 55 #include <sys/vnode.h> 56 #include <sys/mount.h> 57 #include <sys/buf.h> 58 #include <ufs/ufs/inode.h> 59 #include <ufs/ufs/ufsmount.h> 60 #include <ufs/ufs/ufs_extern.h> 61 #include <ufs/ffs/fs.h> 62 #include <ufs/ffs/ffs_extern.h> 63 #include <ufs/ufs/ufs_bswap.h> 64 65 /* 66 * Return buffer with the contents of block "offset" from the beginning of 67 * directory "ip". If "res" is non-zero, fill it in with a pointer to the 68 * remaining space in the directory. 69 */ 70 int 71 ffs_blkatoff(v) 72 void *v; 73 { 74 struct vop_blkatoff_args /* { 75 struct vnode *a_vp; 76 off_t a_offset; 77 char **a_res; 78 struct buf **a_bpp; 79 } */ *ap = v; 80 struct inode *ip; 81 struct fs *fs; 82 struct buf *bp; 83 ufs_daddr_t lbn; 84 int bsize, error; 85 86 ip = VTOI(ap->a_vp); 87 fs = ip->i_fs; 88 lbn = lblkno(fs, ap->a_offset); 89 bsize = blksize(fs, ip, lbn); 90 91 *ap->a_bpp = NULL; 92 if ((error = bread(ap->a_vp, lbn, bsize, NOCRED, &bp)) != 0) { 93 brelse(bp); 94 return (error); 95 } 96 if (ap->a_res) 97 *ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset); 98 *ap->a_bpp = bp; 99 return (0); 100 } 101 #endif 102 103 /* 104 * Update the frsum fields to reflect addition or deletion 105 * of some frags. 106 */ 107 void 108 ffs_fragacct(fs, fragmap, fraglist, cnt, needswap) 109 struct fs *fs; 110 int fragmap; 111 int32_t fraglist[]; 112 int cnt; 113 int needswap; 114 { 115 int inblk; 116 int field, subfield; 117 int siz, pos; 118 119 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 120 fragmap <<= 1; 121 for (siz = 1; siz < fs->fs_frag; siz++) { 122 if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0) 123 continue; 124 field = around[siz]; 125 subfield = inside[siz]; 126 for (pos = siz; pos <= fs->fs_frag; pos++) { 127 if ((fragmap & field) == subfield) { 128 fraglist[siz] = ufs_rw32( 129 ufs_rw32(fraglist[siz], needswap) + cnt, 130 needswap); 131 pos += siz; 132 field <<= siz; 133 subfield <<= siz; 134 } 135 field <<= 1; 136 subfield <<= 1; 137 } 138 } 139 } 140 141 #if defined(_KERNEL) && defined(DIAGNOSTIC) 142 void 143 ffs_checkoverlap(bp, ip) 144 struct buf *bp; 145 struct inode *ip; 146 { 147 struct buf *ebp, *ep; 148 ufs_daddr_t start, last; 149 struct vnode *vp; 150 151 ebp = &buf[nbuf]; 152 start = bp->b_blkno; 153 last = start + btodb(bp->b_bcount) - 1; 154 for (ep = buf; ep < ebp; ep++) { 155 if (ep == bp || (ep->b_flags & B_INVAL) || 156 ep->b_vp == NULLVP) 157 continue; 158 if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0, NULL)) 159 continue; 160 if (vp != ip->i_devvp) 161 continue; 162 /* look for overlap */ 163 if (ep->b_bcount == 0 || ep->b_blkno > last || 164 ep->b_blkno + btodb(ep->b_bcount) <= start) 165 continue; 166 vprint("Disk overlap", vp); 167 printf("\tstart %d, end %d overlap start %d, end %ld\n", 168 start, last, ep->b_blkno, 169 ep->b_blkno + btodb(ep->b_bcount) - 1); 170 panic("Disk buffer overlap"); 171 } 172 } 173 #endif /* DIAGNOSTIC */ 174 175 /* 176 * block operations 177 * 178 * check if a block is available 179 */ 180 int 181 ffs_isblock(fs, cp, h) 182 struct fs *fs; 183 u_char *cp; 184 ufs_daddr_t h; 185 { 186 u_char mask; 187 188 switch ((int)fs->fs_frag) { 189 case 8: 190 return (cp[h] == 0xff); 191 case 4: 192 mask = 0x0f << ((h & 0x1) << 2); 193 return ((cp[h >> 1] & mask) == mask); 194 case 2: 195 mask = 0x03 << ((h & 0x3) << 1); 196 return ((cp[h >> 2] & mask) == mask); 197 case 1: 198 mask = 0x01 << (h & 0x7); 199 return ((cp[h >> 3] & mask) == mask); 200 default: 201 panic("ffs_isblock: unknown fs_frag %d", (int)fs->fs_frag); 202 } 203 } 204 205 /* 206 * check if a block is free 207 */ 208 int 209 ffs_isfreeblock(fs, cp, h) 210 struct fs *fs; 211 u_char *cp; 212 ufs_daddr_t h; 213 { 214 215 switch ((int)fs->fs_frag) { 216 case 8: 217 return (cp[h] == 0); 218 case 4: 219 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 220 case 2: 221 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 222 case 1: 223 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 224 default: 225 panic("ffs_isfreeblock: unknown fs_frag %d", (int)fs->fs_frag); 226 } 227 } 228 229 /* 230 * take a block out of the map 231 */ 232 void 233 ffs_clrblock(fs, cp, h) 234 struct fs *fs; 235 u_char *cp; 236 ufs_daddr_t h; 237 { 238 239 switch ((int)fs->fs_frag) { 240 case 8: 241 cp[h] = 0; 242 return; 243 case 4: 244 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 245 return; 246 case 2: 247 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 248 return; 249 case 1: 250 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 251 return; 252 default: 253 panic("ffs_clrblock: unknown fs_frag %d", (int)fs->fs_frag); 254 } 255 } 256 257 /* 258 * put a block into the map 259 */ 260 void 261 ffs_setblock(fs, cp, h) 262 struct fs *fs; 263 u_char *cp; 264 ufs_daddr_t h; 265 { 266 267 switch ((int)fs->fs_frag) { 268 269 case 8: 270 cp[h] = 0xff; 271 return; 272 case 4: 273 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 274 return; 275 case 2: 276 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 277 return; 278 case 1: 279 cp[h >> 3] |= (0x01 << (h & 0x7)); 280 return; 281 default: 282 panic("ffs_setblock: unknown fs_frag %d", (int)fs->fs_frag); 283 } 284 } 285
Indexes created Tue Sep 30 20:09:53 GMT 2025