| 1 | /* |
| 2 | * Copyright (c) 1982, 1986, 1989 Regents of the University of California. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * %sccs.include.redist.c% |
| 6 | * |
| 7 | * @(#)ffs_subr.c 7.15 (Berkeley) %G% |
| 8 | */ |
| 9 | |
| 10 | #include <sys/param.h> |
| 11 | #include <sys/buf.h> |
| 12 | #include <sys/vnode.h> |
| 13 | |
| 14 | #include <ufs/ufs/quota.h> |
| 15 | #include <ufs/ufs/inode.h> |
| 16 | |
| 17 | #include <ufs/ffs/fs.h> |
| 18 | #include <ufs/ffs/ffs_extern.h> |
| 19 | |
| 20 | /* |
| 21 | * Return buffer with the contents of block "offset" from the beginning of |
| 22 | * directory "ip". If "res" is non-zero, fill it in with a pointer to the |
| 23 | * remaining space in the directory. |
| 24 | */ |
| 25 | int |
| 26 | ffs_blkatoff(vp, offset, res, bpp) |
| 27 | struct vnode *vp; |
| 28 | off_t offset; |
| 29 | char **res; |
| 30 | struct buf **bpp; |
| 31 | { |
| 32 | struct inode *ip; |
| 33 | register struct fs *fs; |
| 34 | struct buf *bp; |
| 35 | daddr_t lbn; |
| 36 | int bsize, error; |
| 37 | |
| 38 | ip = VTOI(vp); |
| 39 | fs = ip->i_fs; |
| 40 | lbn = lblkno(fs, offset); |
| 41 | bsize = blksize(fs, ip, lbn); |
| 42 | |
| 43 | *bpp = NULL; |
| 44 | if (error = bread(vp, lbn, bsize, NOCRED, &bp)) { |
| 45 | brelse(bp); |
| 46 | return (error); |
| 47 | } |
| 48 | if (res) |
| 49 | *res = bp->b_un.b_addr + blkoff(fs, offset); |
| 50 | *bpp = bp; |
| 51 | return (0); |
| 52 | } |
| 53 | |
| 54 | /* |
| 55 | * Update the frsum fields to reflect addition or deletion |
| 56 | * of some frags. |
| 57 | */ |
| 58 | void |
| 59 | ffs_fragacct(fs, fragmap, fraglist, cnt) |
| 60 | struct fs *fs; |
| 61 | int fragmap; |
| 62 | long fraglist[]; |
| 63 | int cnt; |
| 64 | { |
| 65 | int inblk; |
| 66 | register int field, subfield; |
| 67 | register int siz, pos; |
| 68 | |
| 69 | inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; |
| 70 | fragmap <<= 1; |
| 71 | for (siz = 1; siz < fs->fs_frag; siz++) { |
| 72 | if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0) |
| 73 | continue; |
| 74 | field = around[siz]; |
| 75 | subfield = inside[siz]; |
| 76 | for (pos = siz; pos <= fs->fs_frag; pos++) { |
| 77 | if ((fragmap & field) == subfield) { |
| 78 | fraglist[siz] += cnt; |
| 79 | pos += siz; |
| 80 | field <<= siz; |
| 81 | subfield <<= siz; |
| 82 | } |
| 83 | field <<= 1; |
| 84 | subfield <<= 1; |
| 85 | } |
| 86 | } |
| 87 | } |
| 88 | |
| 89 | #ifdef DIAGNOSTIC |
| 90 | void |
| 91 | ffs_checkoverlap(bp, ip) |
| 92 | struct buf *bp; |
| 93 | struct inode *ip; |
| 94 | { |
| 95 | register struct buf *ebp, *ep; |
| 96 | register daddr_t start, last; |
| 97 | struct vnode *vp; |
| 98 | |
| 99 | ebp = &buf[nbuf]; |
| 100 | start = bp->b_blkno; |
| 101 | last = start + btodb(bp->b_bcount) - 1; |
| 102 | for (ep = buf; ep < ebp; ep++) { |
| 103 | if (ep == bp || (ep->b_flags & B_INVAL) || |
| 104 | ep->b_vp == NULLVP) |
| 105 | continue; |
| 106 | if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0)) |
| 107 | continue; |
| 108 | if (vp != ip->i_devvp) |
| 109 | continue; |
| 110 | /* look for overlap */ |
| 111 | if (ep->b_bcount == 0 || ep->b_blkno > last || |
| 112 | ep->b_blkno + btodb(ep->b_bcount) <= start) |
| 113 | continue; |
| 114 | vprint("Disk overlap", vp); |
| 115 | (void)printf("\tstart %d, end %d overlap start %d, end %d\n", |
| 116 | start, last, ep->b_blkno, |
| 117 | ep->b_blkno + btodb(ep->b_bcount) - 1); |
| 118 | panic("Disk buffer overlap"); |
| 119 | } |
| 120 | } |
| 121 | #endif /* DIAGNOSTIC */ |
| 122 | |
| 123 | /* |
| 124 | * block operations |
| 125 | * |
| 126 | * check if a block is available |
| 127 | */ |
| 128 | int |
| 129 | ffs_isblock(fs, cp, h) |
| 130 | struct fs *fs; |
| 131 | unsigned char *cp; |
| 132 | daddr_t h; |
| 133 | { |
| 134 | unsigned char mask; |
| 135 | |
| 136 | switch ((int)fs->fs_frag) { |
| 137 | case 8: |
| 138 | return (cp[h] == 0xff); |
| 139 | case 4: |
| 140 | mask = 0x0f << ((h & 0x1) << 2); |
| 141 | return ((cp[h >> 1] & mask) == mask); |
| 142 | case 2: |
| 143 | mask = 0x03 << ((h & 0x3) << 1); |
| 144 | return ((cp[h >> 2] & mask) == mask); |
| 145 | case 1: |
| 146 | mask = 0x01 << (h & 0x7); |
| 147 | return ((cp[h >> 3] & mask) == mask); |
| 148 | default: |
| 149 | panic("ffs_isblock"); |
| 150 | } |
| 151 | } |
| 152 | |
| 153 | /* |
| 154 | * take a block out of the map |
| 155 | */ |
| 156 | void |
| 157 | ffs_clrblock(fs, cp, h) |
| 158 | struct fs *fs; |
| 159 | u_char *cp; |
| 160 | daddr_t h; |
| 161 | { |
| 162 | |
| 163 | switch ((int)fs->fs_frag) { |
| 164 | case 8: |
| 165 | cp[h] = 0; |
| 166 | return; |
| 167 | case 4: |
| 168 | cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); |
| 169 | return; |
| 170 | case 2: |
| 171 | cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); |
| 172 | return; |
| 173 | case 1: |
| 174 | cp[h >> 3] &= ~(0x01 << (h & 0x7)); |
| 175 | return; |
| 176 | default: |
| 177 | panic("ffs_clrblock"); |
| 178 | } |
| 179 | } |
| 180 | |
| 181 | /* |
| 182 | * put a block into the map |
| 183 | */ |
| 184 | void |
| 185 | ffs_setblock(fs, cp, h) |
| 186 | struct fs *fs; |
| 187 | unsigned char *cp; |
| 188 | daddr_t h; |
| 189 | { |
| 190 | |
| 191 | switch ((int)fs->fs_frag) { |
| 192 | |
| 193 | case 8: |
| 194 | cp[h] = 0xff; |
| 195 | return; |
| 196 | case 4: |
| 197 | cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); |
| 198 | return; |
| 199 | case 2: |
| 200 | cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); |
| 201 | return; |
| 202 | case 1: |
| 203 | cp[h >> 3] |= (0x01 << (h & 0x7)); |
| 204 | return; |
| 205 | default: |
| 206 | panic("ffs_setblock"); |
| 207 | } |
| 208 | } |
| 209 | |
| 210 | #if (!defined(vax) && !defined(tahoe) && !defined(hp300)) \ |
| 211 | || defined(VAX630) || defined(VAX650) |
| 212 | /* |
| 213 | * C definitions of special instructions. |
| 214 | * Normally expanded with inline. |
| 215 | */ |
| 216 | int |
| 217 | scanc(size, cp, table, mask) |
| 218 | u_int size; |
| 219 | register u_char *cp, table[]; |
| 220 | register u_char mask; |
| 221 | { |
| 222 | register u_char *end = &cp[size]; |
| 223 | |
| 224 | while (cp < end && (table[*cp] & mask) == 0) |
| 225 | cp++; |
| 226 | return (end - cp); |
| 227 | } |
| 228 | #endif |
| 229 | |
| 230 | #if !defined(vax) && !defined(tahoe) && !defined(hp300) |
| 231 | int |
| 232 | skpc(mask, size, cp) |
| 233 | register u_char mask; |
| 234 | u_int size; |
| 235 | register u_char *cp; |
| 236 | { |
| 237 | register u_char *end = &cp[size]; |
| 238 | |
| 239 | while (cp < end && *cp == mask) |
| 240 | cp++; |
| 241 | return (end - cp); |
| 242 | } |
| 243 | |
| 244 | int |
| 245 | locc(mask, size, cp) |
| 246 | register u_char mask; |
| 247 | u_int size; |
| 248 | register u_char *cp; |
| 249 | { |
| 250 | register u_char *end = &cp[size]; |
| 251 | |
| 252 | while (cp < end && *cp != mask) |
| 253 | cp++; |
| 254 | return (end - cp); |
| 255 | } |
| 256 | #endif |