i386/linux-2.3.21/fs/ufs/util.h

   1 /*
   2  *  linux/fs/ufs/util.h
   3  *
   4  * Copyright (C) 1998
   5  * Daniel Pirkl <daniel.pirkl@email.cz>
   6  * Charles University, Faculty of Mathematics and Physics
   7  */
   8
   9 #include <linux/fs.h>
  10 #include "swab.h"
  11
  12
  13 /*
  14  * some useful macros
  15  */
  16 #define in_range(b,first,len)   ((b)>=(first)&&(b)<(first)+(len))
  17 #define howmany(x,y)            (((x)+(y)-1)/(y))
  18 #define min(x,y)                ((x)<(y)?(x):(y))
  19 #define max(x,y)                ((x)>(y)?(x):(y))
  20
  21
  22
  23 /*
  24  * macros used for retyping
  25  */
  26 #define UCPI_UBH ((struct ufs_buffer_head *)ucpi)
  27 #define USPI_UBH ((struct ufs_buffer_head *)uspi)
  28
  29
  30
  31 /*
  32  * macros used for accesing structures
  33  */
  34 #define ufs_get_fs_state(usb1,usb3) _ufs_get_fs_state_(usb1,usb3,flags,swab)
  35 static inline __s32 _ufs_get_fs_state_(struct ufs_super_block_first * usb1,
  36         struct ufs_super_block_third * usb3, unsigned flags, unsigned swab)
  37 {
  38         switch (flags & UFS_ST_MASK) {
  39                 case UFS_ST_SUN:
  40                         return SWAB32((usb3)->fs_u2.fs_sun.fs_state);
  41                 case UFS_ST_SUNx86:
  42                         return SWAB32((usb1)->fs_u1.fs_sunx86.fs_state);
  43                 case UFS_ST_44BSD:
  44                 default:
  45                         return SWAB32((usb3)->fs_u2.fs_44.fs_state);
  46         }
  47 }
  48
  49 #define ufs_set_fs_state(usb1,usb3,value) _ufs_set_fs_state_(usb1,usb3,value,flags,swab)
  50 static inline void _ufs_set_fs_state_(struct ufs_super_block_first * usb1,
  51         struct ufs_super_block_third * usb3, __s32 value, unsigned flags, unsigned swab)
  52 {
  53         switch (flags & UFS_ST_MASK) {
  54                 case UFS_ST_SUN:
  55                         (usb3)->fs_u2.fs_sun.fs_state = SWAB32(value);
  56                         break;
  57                 case UFS_ST_SUNx86:
  58                         (usb1)->fs_u1.fs_sunx86.fs_state = SWAB32(value);
  59                         break;
  60                 case UFS_ST_44BSD:
  61                         (usb3)->fs_u2.fs_44.fs_state = SWAB32(value);
  62                         break;
  63         }
  64 }
  65
  66 #define ufs_get_fs_npsect(usb1,usb3) _ufs_get_fs_npsect_(usb1,usb3,flags,swab)
  67 static inline __u32 _ufs_get_fs_npsect_(struct ufs_super_block_first * usb1,
  68         struct ufs_super_block_third * usb3, unsigned flags, unsigned swab)
  69 {
  70         if ((flags & UFS_ST_MASK) == UFS_ST_SUNx86)
  71                 return SWAB32((usb3)->fs_u2.fs_sunx86.fs_npsect);
  72         else
  73                 return SWAB32((usb1)->fs_u1.fs_sun.fs_npsect);
  74 }
  75
  76 #define ufs_get_fs_qbmask(usb3) _ufs_get_fs_qbmask_(usb3,flags,swab)
  77 static inline __u64 _ufs_get_fs_qbmask_(struct ufs_super_block_third * usb3,
  78         unsigned flags, unsigned swab)
  79 {
  80         __u64 tmp;
  81         switch (flags & UFS_ST_MASK) {
  82                 case UFS_ST_SUN:
  83                         ((u32 *)&tmp)[0] = usb3->fs_u2.fs_sun.fs_qbmask[0];
  84                         ((u32 *)&tmp)[1] = usb3->fs_u2.fs_sun.fs_qbmask[1];
  85                         break;
  86                 case UFS_ST_SUNx86:
  87                         ((u32 *)&tmp)[0] = usb3->fs_u2.fs_sunx86.fs_qbmask[0];
  88                         ((u32 *)&tmp)[1] = usb3->fs_u2.fs_sunx86.fs_qbmask[1];
  89                         break;
  90                 case UFS_ST_44BSD:
  91                         ((u32 *)&tmp)[0] = usb3->fs_u2.fs_44.fs_qbmask[0];
  92                         ((u32 *)&tmp)[1] = usb3->fs_u2.fs_44.fs_qbmask[1];
  93                         break;
  94         }
  95         return SWAB64(tmp);
  96 }
  97
  98 #define ufs_get_fs_qfmask(usb3) _ufs_get_fs_qfmask_(usb3,flags,swab)
  99 static inline __u64 _ufs_get_fs_qfmask_(struct ufs_super_block_third * usb3,
 100         unsigned flags, unsigned swab)
 101 {
 102         __u64 tmp;
 103         switch (flags & UFS_ST_MASK) {
 104                 case UFS_ST_SUN:
 105                         ((u32 *)&tmp)[0] = usb3->fs_u2.fs_sun.fs_qfmask[0];
 106                         ((u32 *)&tmp)[1] = usb3->fs_u2.fs_sun.fs_qfmask[1];
 107                         break;
 108                 case UFS_ST_SUNx86:
 109                         ((u32 *)&tmp)[0] = usb3->fs_u2.fs_sunx86.fs_qfmask[0];
 110                         ((u32 *)&tmp)[1] = usb3->fs_u2.fs_sunx86.fs_qfmask[1];
 111                         break;
 112                 case UFS_ST_44BSD:
 113                         ((u32 *)&tmp)[0] = usb3->fs_u2.fs_44.fs_qfmask[0];
 114                         ((u32 *)&tmp)[1] = usb3->fs_u2.fs_44.fs_qfmask[1];
 115                         break;
 116         }
 117         return SWAB64(tmp);
 118 }
 119
 120 #define ufs_get_de_namlen(de) \
 121         (((flags & UFS_DE_MASK) == UFS_DE_OLD) \
 122         ? SWAB16(de->d_u.d_namlen) \
 123         : de->d_u.d_44.d_namlen)
 124
 125 #define ufs_set_de_namlen(de,value) \
 126         (((flags & UFS_DE_MASK) == UFS_DE_OLD) \
 127         ? (de->d_u.d_namlen = SWAB16(value)) \
 128         : (de->d_u.d_44.d_namlen = value))
 129
 130 #define ufs_set_de_type(de,mode) _ufs_set_de_type_(de,mode,flags,swab)
 131 static inline void _ufs_set_de_type_(struct ufs_dir_entry * de, int mode,
 132         unsigned flags, unsigned swab)
 133 {
 134         if ((flags & UFS_DE_MASK) == UFS_DE_44BSD) {
 135                 switch (mode & S_IFMT) {
 136                         case S_IFSOCK: de->d_u.d_44.d_type = DT_SOCK; break;
 137                         case S_IFLNK: de->d_u.d_44.d_type = DT_LNK; break;
 138                         case S_IFREG: de->d_u.d_44.d_type = DT_REG; break;
 139                         case S_IFBLK: de->d_u.d_44.d_type = DT_BLK; break;
 140                         case S_IFDIR: de->d_u.d_44.d_type = DT_DIR; break;
 141                         case S_IFCHR: de->d_u.d_44.d_type = DT_CHR; break;
 142                         case S_IFIFO: de->d_u.d_44.d_type = DT_FIFO; break;
 143                         default: de->d_u.d_44.d_type = DT_UNKNOWN;
 144                 }
 145         }
 146 }
 147
 148 #define ufs_get_inode_uid(inode) _ufs_get_inode_uid_(inode,flags,swab)
 149 static inline __u32 _ufs_get_inode_uid_(struct ufs_inode * inode,
 150         unsigned flags, unsigned swab)
 151 {
 152         switch (flags & UFS_UID_MASK) {
 153                 case UFS_UID_EFT:
 154                         return SWAB32(inode->ui_u3.ui_sun.ui_uid);
 155                 case UFS_UID_44BSD:
 156                         return SWAB32(inode->ui_u3.ui_44.ui_uid);
 157                 default:
 158                         return SWAB16(inode->ui_u1.oldids.ui_suid);
 159         }
 160 }
 161
 162 #define ufs_set_inode_uid(inode,value) _ufs_set_inode_uid_(inode,value,flags,swab)
 163 static inline void _ufs_set_inode_uid_(struct ufs_inode * inode, __u32 value,
 164         unsigned flags, unsigned swab)
 165 {
 166         inode->ui_u1.oldids.ui_suid = SWAB16(value);
 167         switch (flags & UFS_UID_MASK) {
 168                 case UFS_UID_EFT:
 169                         inode->ui_u3.ui_sun.ui_uid = SWAB32(value);
 170                         break;
 171                 case UFS_UID_44BSD:
 172                         inode->ui_u3.ui_44.ui_uid = SWAB32(value);
 173                         break;
 174         }
 175 }
 176
 177 #define ufs_get_inode_gid(inode) _ufs_get_inode_gid_(inode,flags,swab)
 178 static inline __u32 _ufs_get_inode_gid_(struct ufs_inode * inode,
 179         unsigned flags, unsigned swab)
 180 {
 181         switch (flags & UFS_UID_MASK) {
 182                 case UFS_UID_EFT:
 183                         return SWAB32(inode->ui_u3.ui_sun.ui_gid);
 184                 case UFS_UID_44BSD:
 185                         return SWAB32(inode->ui_u3.ui_44.ui_gid);
 186                 default:
 187                         return SWAB16(inode->ui_u1.oldids.ui_sgid);
 188         }
 189 }
 190
 191 #define ufs_set_inode_gid(inode,value) _ufs_set_inode_gid_(inode,value,flags,swab)
 192 static inline void _ufs_set_inode_gid_(struct ufs_inode * inode, __u32 value,
 193         unsigned flags, unsigned swab)
 194 {
 195         inode->ui_u1.oldids.ui_sgid =  SWAB16(value);
 196         switch (flags & UFS_UID_MASK) {
 197                 case UFS_UID_EFT:
 198                         inode->ui_u3.ui_sun.ui_gid = SWAB32(value);
 199                         break;
 200                 case UFS_UID_44BSD:
 201                         inode->ui_u3.ui_44.ui_gid = SWAB32(value);
 202                         break;
 203         }
 204 }
 205
 206
 207
 208 /*
 209  * These functions manipulate ufs buffers
 210  */
 211 #define ubh_bread(dev,fragment,size) _ubh_bread_(uspi,dev,fragment,size)
 212 extern struct ufs_buffer_head * _ubh_bread_(struct ufs_sb_private_info *, kdev_t, unsigned, unsigned);
 213 extern struct ufs_buffer_head * ubh_bread_uspi(struct ufs_sb_private_info *, kdev_t, unsigned, unsigned);
 214 extern void ubh_brelse (struct ufs_buffer_head *);
 215 extern void ubh_brelse_uspi (struct ufs_sb_private_info *);
 216 extern void ubh_mark_buffer_dirty (struct ufs_buffer_head *, int);
 217 extern void ubh_mark_buffer_uptodate (struct ufs_buffer_head *, int);
 218 extern void ubh_ll_rw_block (int, unsigned, struct ufs_buffer_head **);
 219 extern void ubh_wait_on_buffer (struct ufs_buffer_head *);
 220 extern unsigned ubh_max_bcount (struct ufs_buffer_head *);
 221 extern void ubh_bforget (struct ufs_buffer_head *);
 222 extern int  ubh_buffer_dirty (struct ufs_buffer_head *);
 223 #define ubh_ubhcpymem(mem,ubh,size) _ubh_ubhcpymem_(uspi,mem,ubh,size)
 224 extern void _ubh_ubhcpymem_(struct ufs_sb_private_info *, unsigned char *, struct ufs_buffer_head *, unsigned);
 225 #define ubh_memcpyubh(ubh,mem,size) _ubh_memcpyubh_(uspi,ubh,mem,size)
 226 extern void _ubh_memcpyubh_(struct ufs_sb_private_info *, struct ufs_buffer_head *, unsigned char *, unsigned);
 227
 228
 229
 230 /*
 231  * macros to get important structures from ufs_buffer_head
 232  */
 233 #define ubh_get_usb_first(ubh) \
 234         ((struct ufs_super_block_first *)((ubh)->bh[0]->b_data))
 235
 236 #define ubh_get_usb_second(ubh) \
 237         ((struct ufs_super_block_second *)(ubh)-> \
 238         bh[UFS_SECTOR_SIZE >> uspi->s_fshift]->b_data + (UFS_SECTOR_SIZE & ~uspi->s_fmask))
 239
 240 #define ubh_get_usb_third(ubh) \
 241         ((struct ufs_super_block_third *)((ubh)-> \
 242         bh[UFS_SECTOR_SIZE*2 >> uspi->s_fshift]->b_data + (UFS_SECTOR_SIZE*2 & ~uspi->s_fmask)))
 243
 244 #define ubh_get_ucg(ubh) \
 245         ((struct ufs_cylinder_group *)((ubh)->bh[0]->b_data))
 246
 247
 248 /*
 249  * Extract byte from ufs_buffer_head
 250  * Extract the bits for a block from a map inside ufs_buffer_head
 251  */
 252 #define ubh_get_addr8(ubh,begin) \
 253         ((u8*)(ubh)->bh[(begin) >> uspi->s_fshift]->b_data + \
 254         ((begin) & ~uspi->s_fmask))
 255
 256 #define ubh_get_addr16(ubh,begin) \
 257         (((u16*)((ubh)->bh[(begin) >> (uspi->s_fshift-1)]->b_data)) + \
 258         ((begin) & (uspi->fsize>>1) - 1)))
 259
 260 #define ubh_get_addr32(ubh,begin) \
 261         (((u32*)((ubh)->bh[(begin) >> (uspi->s_fshift-2)]->b_data)) + \
 262         ((begin) & ((uspi->s_fsize>>2) - 1)))
 263
 264 #define ubh_get_addr ubh_get_addr8
 265
 266 #define ubh_blkmap(ubh,begin,bit) \
 267         ((*ubh_get_addr(ubh, (begin) + ((bit) >> 3)) >> ((bit) & 7)) & (0xff >> (UFS_MAXFRAG - uspi->s_fpb)))
 268
 269
 270 /*
 271  * Macros for access to superblock array structures
 272  */
 273 #define ubh_postbl(ubh,cylno,i) \
 274         ((uspi->s_postblformat != UFS_DYNAMICPOSTBLFMT) \
 275         ? (*(__s16*)(ubh_get_addr(ubh, \
 276         (unsigned)(&((struct ufs_super_block *)0)->fs_opostbl) \
 277         + (((cylno) * 16 + (i)) << 1) ) )) \
 278         : (*(__s16*)(ubh_get_addr(ubh, \
 279         uspi->s_postbloff + (((cylno) * uspi->s_nrpos + (i)) << 1) ))))
 280
 281 #define ubh_rotbl(ubh,i) \
 282         ((uspi->s_postblformat != UFS_DYNAMICPOSTBLFMT) \
 283         ? (*(__u8*)(ubh_get_addr(ubh, \
 284         (unsigned)(&((struct ufs_super_block *)0)->fs_space) + (i)))) \
 285         : (*(__u8*)(ubh_get_addr(ubh, uspi->s_rotbloff + (i)))))
 286
 287 /*
 288  * Determine the number of available frags given a
 289  * percentage to hold in reserve.
 290  */
 291 #define ufs_freespace(usb, percentreserved) \
 292         (ufs_blkstofrags(SWAB32((usb)->fs_cstotal.cs_nbfree)) + \
 293         SWAB32((usb)->fs_cstotal.cs_nffree) - (uspi->s_dsize * (percentreserved) / 100))
 294
 295 /*
 296  * Macros to access cylinder group array structures
 297  */
 298 #define ubh_cg_blktot(ucpi,cylno) \
 299         (*((__u32*)ubh_get_addr(UCPI_UBH, (ucpi)->c_btotoff + ((cylno) << 2))))
 300
 301 #define ubh_cg_blks(ucpi,cylno,rpos) \
 302         (*((__u16*)ubh_get_addr(UCPI_UBH, \
 303         (ucpi)->c_boff + (((cylno) * uspi->s_nrpos + (rpos)) << 1 ))))
 304
 305 /*
 306  * Bitmap operations
 307  * These functions work like classical bitmap operations.
 308  * The difference is that we don't have the whole bitmap
 309  * in one contiguous chunk of memory, but in several buffers.
 310  * The parameters of each function are super_block, ufs_buffer_head and
 311  * position of the beginning of the bitmap.
 312  */
 313 #define ubh_setbit(ubh,begin,bit) \
 314         (*ubh_get_addr(ubh, (begin) + ((bit) >> 3)) |= (1 << ((bit) & 7)))
 315
 316 #define ubh_clrbit(ubh,begin,bit) \
 317         (*ubh_get_addr (ubh, (begin) + ((bit) >> 3)) &= ~(1 << ((bit) & 7)))
 318
 319 #define ubh_isset(ubh,begin,bit) \
 320         (*ubh_get_addr (ubh, (begin) + ((bit) >> 3)) & (1 << ((bit) & 7)))
 321
 322 #define ubh_isclr(ubh,begin,bit) (!ubh_isset(ubh,begin,bit))
 323
 324 #define ubh_find_first_zero_bit(ubh,begin,size) _ubh_find_next_zero_bit_(uspi,ubh,begin,size,0)
 325
 326 #define ubh_find_next_zero_bit(ubh,begin,size,offset) _ubh_find_next_zero_bit_(uspi,ubh,begin,size,offset)
 327 static inline unsigned _ubh_find_next_zero_bit_(
 328         struct ufs_sb_private_info * uspi, struct ufs_buffer_head * ubh,
 329         unsigned begin, unsigned size, unsigned offset)
 330 {
 331         unsigned base, count, pos;
 332
 333         size -= offset;
 334         begin <<= 3;
 335         offset += begin;
 336         base = offset >> uspi->s_bpfshift;
 337         offset &= uspi->s_bpfmask;
 338         for (;;) {
 339                 count = min (size + offset, uspi->s_bpf);
 340                 size -= count - offset;
 341                 pos = ext2_find_next_zero_bit (ubh->bh[base]->b_data, count, offset);
 342                 if (pos < count || !size)
 343                         break;
 344                 base++;
 345                 offset = 0;
 346         }
 347         return (base << uspi->s_bpfshift) + pos - begin;
 348 }
 349
 350 static inline unsigned find_last_zero_bit (unsigned char * bitmap,
 351         unsigned size, unsigned offset)
 352 {
 353         unsigned bit, i;
 354         unsigned char * mapp;
 355         unsigned char map;
 356
 357         mapp = bitmap + (size >> 3);
 358         map = *mapp--;
 359         bit = 1 << (size & 7);
 360         for (i = size; i > offset; i--) {
 361                 if ((map & bit) == 0)
 362                         break;
 363                 if ((i & 7) != 0) {
 364                         bit >>= 1;
 365                 } else {
 366                         map = *mapp--;
 367                         bit = 1 << 7;
 368                 }
 369         }
 370         return i;
 371 }
 372
 373 #define ubh_find_last_zero_bit(ubh,begin,size,offset) _ubh_find_last_zero_bit_(uspi,ubh,begin,size,offset)
 374 static inline unsigned _ubh_find_last_zero_bit_(
 375         struct ufs_sb_private_info * uspi, struct ufs_buffer_head * ubh,
 376         unsigned begin, unsigned start, unsigned end)
 377 {
 378         unsigned base, count, pos, size;
 379
 380         size = start - end;
 381         begin <<= 3;
 382         start += begin;
 383         base = start >> uspi->s_bpfshift;
 384         start &= uspi->s_bpfmask;
 385         for (;;) {
 386                 count = min (size + (uspi->s_bpf - start), uspi->s_bpf)
 387                         - (uspi->s_bpf - start);
 388                 size -= count;
 389                 pos = find_last_zero_bit (ubh->bh[base]->b_data,
 390                         start, start - count);
 391                 if (pos > start - count || !size)
 392                         break;
 393                 base--;
 394                 start = uspi->s_bpf;
 395         }
 396         return (base << uspi->s_bpfshift) + pos - begin;
 397 }
 398
 399 #define ubh_isblockclear(ubh,begin,block) (!_ubh_isblockset_(uspi,ubh,begin,block))
 400
 401 #define ubh_isblockset(ubh,begin,block) _ubh_isblockset_(uspi,ubh,begin,block)
 402 static inline int _ubh_isblockset_(struct ufs_sb_private_info * uspi,
 403         struct ufs_buffer_head * ubh, unsigned begin, unsigned block)
 404 {
 405         switch (uspi->s_fpb) {
 406         case 8:
 407                 return (*ubh_get_addr (ubh, begin + block) == 0xff);
 408         case 4:
 409                 return (*ubh_get_addr (ubh, begin + (block >> 1)) == (0x0f << ((block & 0x01) << 2)));
 410         case 2:
 411                 return (*ubh_get_addr (ubh, begin + (block >> 2)) == (0x03 << ((block & 0x03) << 1)));
 412         case 1:
 413                 return (*ubh_get_addr (ubh, begin + (block >> 3)) == (0x01 << (block & 0x07)));
 414         }
 415         return 0;
 416 }
 417
 418 #define ubh_clrblock(ubh,begin,block) _ubh_clrblock_(uspi,ubh,begin,block)
 419 static inline void _ubh_clrblock_(struct ufs_sb_private_info * uspi,
 420         struct ufs_buffer_head * ubh, unsigned begin, unsigned block)
 421 {
 422         switch (uspi->s_fpb) {
 423         case 8:
 424                 *ubh_get_addr (ubh, begin + block) = 0x00;
 425                 return;
 426         case 4:
 427                 *ubh_get_addr (ubh, begin + (block >> 1)) &= ~(0x0f << ((block & 0x01) << 2));
 428                 return;
 429         case 2:
 430                 *ubh_get_addr (ubh, begin + (block >> 2)) &= ~(0x03 << ((block & 0x03) << 1));
 431                 return;
 432         case 1:
 433                 *ubh_get_addr (ubh, begin + (block >> 3)) &= ~(0x01 << ((block & 0x07)));
 434                 return;
 435         }
 436 }
 437
 438 #define ubh_setblock(ubh,begin,block) _ubh_setblock_(uspi,ubh,begin,block)
 439 static inline void _ubh_setblock_(struct ufs_sb_private_info * uspi,
 440         struct ufs_buffer_head * ubh, unsigned begin, unsigned block)
 441 {
 442         switch (uspi->s_fpb) {
 443         case 8:
 444                 *ubh_get_addr(ubh, begin + block) = 0xff;
 445                 return;
 446         case 4:
 447                 *ubh_get_addr(ubh, begin + (block >> 1)) |= (0x0f << ((block & 0x01) << 2));
 448                 return;
 449         case 2:
 450                 *ubh_get_addr(ubh, begin + (block >> 2)) |= (0x03 << ((block & 0x03) << 1));
 451                 return;
 452         case 1:
 453                 *ubh_get_addr(ubh, begin + (block >> 3)) |= (0x01 << ((block & 0x07)));
 454                 return;
 455         }
 456 }
 457
 458 static inline void ufs_fragacct (struct super_block * sb, unsigned blockmap,
 459         unsigned * fraglist, int cnt)
 460 {
 461         struct ufs_sb_private_info * uspi;
 462         unsigned fragsize, pos;
 463         unsigned swab;
 464
 465         swab = sb->u.ufs_sb.s_swab;
 466         uspi = sb->u.ufs_sb.s_uspi;
 467
 468         fragsize = 0;
 469         for (pos = 0; pos < uspi->s_fpb; pos++) {
 470                 if (blockmap & (1 << pos)) {
 471                         fragsize++;
 472                 }
 473                 else if (fragsize > 0) {
 474                         ADD_SWAB32(fraglist[fragsize], cnt);
 475                         fragsize = 0;
 476                 }
 477         }
 478         if (fragsize > 0 && fragsize < uspi->s_fpb)
 479                 ADD_SWAB32(fraglist[fragsize], cnt);
 480 }
 481
 482 #define ubh_scanc(ubh,begin,size,table,mask) _ubh_scanc_(uspi,ubh,begin,size,table,mask)
 483 static inline unsigned _ubh_scanc_(struct ufs_sb_private_info * uspi, struct ufs_buffer_head * ubh,
 484         unsigned begin, unsigned size, unsigned char * table, unsigned char mask)
 485 {
 486         unsigned rest, offset;
 487         unsigned char * cp;
 488
 489
 490         offset = begin & ~uspi->s_fmask;
 491         begin >>= uspi->s_fshift;
 492         for (;;) {
 493                 if ((offset + size) < uspi->s_fsize)
 494                         rest = size;
 495                 else
 496                         rest = uspi->s_fsize - offset;
 497                 size -= rest;
 498                 cp = ubh->bh[begin]->b_data + offset;
 499                 while ((table[*cp++] & mask) == 0 && --rest);
 500                 if (rest || !size)
 501                         break;
 502                 begin++;
 503                 offset = 0;
 504         }
 505         return (size + rest);
 506 }