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/buffer_head.h>
  10 #include <linux/fs.h>
  11 #include "swab.h"
  12
  13
  14 /*
  15  * some useful macros
  16  */
  17 #define in_range(b,first,len)   ((b)>=(first)&&(b)<(first)+(len))
  18
  19 /*
  20  * macros used for retyping
  21  */
  22 #define UCPI_UBH ((struct ufs_buffer_head *)ucpi)
  23 #define USPI_UBH ((struct ufs_buffer_head *)uspi)
  24
  25
  26
  27 /*
  28  * macros used for accessing structures
  29  */
  30 static inline s32
  31 ufs_get_fs_state(struct super_block *sb, struct ufs_super_block_first *usb1,
  32                  struct ufs_super_block_third *usb3)
  33 {
  34         switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
  35         case UFS_ST_SUN:
  36                 return fs32_to_cpu(sb, usb3->fs_u2.fs_sun.fs_state);
  37         case UFS_ST_SUNx86:
  38                 return fs32_to_cpu(sb, usb1->fs_u1.fs_sunx86.fs_state);
  39         case UFS_ST_44BSD:
  40         default:
  41                 return fs32_to_cpu(sb, usb3->fs_u2.fs_44.fs_state);
  42         }
  43 }
  44
  45 static inline void
  46 ufs_set_fs_state(struct super_block *sb, struct ufs_super_block_first *usb1,
  47                  struct ufs_super_block_third *usb3, s32 value)
  48 {
  49         switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
  50         case UFS_ST_SUN:
  51                 usb3->fs_u2.fs_sun.fs_state = cpu_to_fs32(sb, value);
  52                 break;
  53         case UFS_ST_SUNx86:
  54                 usb1->fs_u1.fs_sunx86.fs_state = cpu_to_fs32(sb, value);
  55                 break;
  56         case UFS_ST_44BSD:
  57                 usb3->fs_u2.fs_44.fs_state = cpu_to_fs32(sb, value);
  58                 break;
  59         }
  60 }
  61
  62 static inline u32
  63 ufs_get_fs_npsect(struct super_block *sb, struct ufs_super_block_first *usb1,
  64                   struct ufs_super_block_third *usb3)
  65 {
  66         if ((UFS_SB(sb)->s_flags & UFS_ST_MASK) == UFS_ST_SUNx86)
  67                 return fs32_to_cpu(sb, usb3->fs_u2.fs_sunx86.fs_npsect);
  68         else
  69                 return fs32_to_cpu(sb, usb1->fs_u1.fs_sun.fs_npsect);
  70 }
  71
  72 static inline u64
  73 ufs_get_fs_qbmask(struct super_block *sb, struct ufs_super_block_third *usb3)
  74 {
  75         __fs64 tmp;
  76
  77         switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
  78         case UFS_ST_SUN:
  79                 ((__fs32 *)&tmp)[0] = usb3->fs_u2.fs_sun.fs_qbmask[0];
  80                 ((__fs32 *)&tmp)[1] = usb3->fs_u2.fs_sun.fs_qbmask[1];
  81                 break;
  82         case UFS_ST_SUNx86:
  83                 ((__fs32 *)&tmp)[0] = usb3->fs_u2.fs_sunx86.fs_qbmask[0];
  84                 ((__fs32 *)&tmp)[1] = usb3->fs_u2.fs_sunx86.fs_qbmask[1];
  85                 break;
  86         case UFS_ST_44BSD:
  87                 ((__fs32 *)&tmp)[0] = usb3->fs_u2.fs_44.fs_qbmask[0];
  88                 ((__fs32 *)&tmp)[1] = usb3->fs_u2.fs_44.fs_qbmask[1];
  89                 break;
  90         }
  91
  92         return fs64_to_cpu(sb, tmp);
  93 }
  94
  95 static inline u64
  96 ufs_get_fs_qfmask(struct super_block *sb, struct ufs_super_block_third *usb3)
  97 {
  98         __fs64 tmp;
  99
 100         switch (UFS_SB(sb)->s_flags & UFS_ST_MASK) {
 101         case UFS_ST_SUN:
 102                 ((__fs32 *)&tmp)[0] = usb3->fs_u2.fs_sun.fs_qfmask[0];
 103                 ((__fs32 *)&tmp)[1] = usb3->fs_u2.fs_sun.fs_qfmask[1];
 104                 break;
 105         case UFS_ST_SUNx86:
 106                 ((__fs32 *)&tmp)[0] = usb3->fs_u2.fs_sunx86.fs_qfmask[0];
 107                 ((__fs32 *)&tmp)[1] = usb3->fs_u2.fs_sunx86.fs_qfmask[1];
 108                 break;
 109         case UFS_ST_44BSD:
 110                 ((__fs32 *)&tmp)[0] = usb3->fs_u2.fs_44.fs_qfmask[0];
 111                 ((__fs32 *)&tmp)[1] = usb3->fs_u2.fs_44.fs_qfmask[1];
 112                 break;
 113         }
 114
 115         return fs64_to_cpu(sb, tmp);
 116 }
 117
 118 static inline u16
 119 ufs_get_de_namlen(struct super_block *sb, struct ufs_dir_entry *de)
 120 {
 121         if ((UFS_SB(sb)->s_flags & UFS_DE_MASK) == UFS_DE_OLD)
 122                 return fs16_to_cpu(sb, de->d_u.d_namlen);
 123         else
 124                 return de->d_u.d_44.d_namlen; /* XXX this seems wrong */
 125 }
 126
 127 static inline void
 128 ufs_set_de_namlen(struct super_block *sb, struct ufs_dir_entry *de, u16 value)
 129 {
 130         if ((UFS_SB(sb)->s_flags & UFS_DE_MASK) == UFS_DE_OLD)
 131                 de->d_u.d_namlen = cpu_to_fs16(sb, value);
 132         else
 133                 de->d_u.d_44.d_namlen = value; /* XXX this seems wrong */
 134 }
 135
 136 static inline void
 137 ufs_set_de_type(struct super_block *sb, struct ufs_dir_entry *de, int mode)
 138 {
 139         if ((UFS_SB(sb)->s_flags & UFS_DE_MASK) != UFS_DE_44BSD)
 140                 return;
 141
 142         /*
 143          * TODO turn this into a table lookup
 144          */
 145         switch (mode & S_IFMT) {
 146         case S_IFSOCK:
 147                 de->d_u.d_44.d_type = DT_SOCK;
 148                 break;
 149         case S_IFLNK:
 150                 de->d_u.d_44.d_type = DT_LNK;
 151                 break;
 152         case S_IFREG:
 153                 de->d_u.d_44.d_type = DT_REG;
 154                 break;
 155         case S_IFBLK:
 156                 de->d_u.d_44.d_type = DT_BLK;
 157                 break;
 158         case S_IFDIR:
 159                 de->d_u.d_44.d_type = DT_DIR;
 160                 break;
 161         case S_IFCHR:
 162                 de->d_u.d_44.d_type = DT_CHR;
 163                 break;
 164         case S_IFIFO:
 165                 de->d_u.d_44.d_type = DT_FIFO;
 166                 break;
 167         default:
 168                 de->d_u.d_44.d_type = DT_UNKNOWN;
 169         }
 170 }
 171
 172 static inline u32
 173 ufs_get_inode_uid(struct super_block *sb, struct ufs_inode *inode)
 174 {
 175         switch (UFS_SB(sb)->s_flags & UFS_UID_MASK) {
 176         case UFS_UID_EFT:
 177                 return fs32_to_cpu(sb, inode->ui_u3.ui_sun.ui_uid);
 178         case UFS_UID_44BSD:
 179                 return fs32_to_cpu(sb, inode->ui_u3.ui_44.ui_uid);
 180         default:
 181                 return fs16_to_cpu(sb, inode->ui_u1.oldids.ui_suid);
 182         }
 183 }
 184
 185 static inline void
 186 ufs_set_inode_uid(struct super_block *sb, struct ufs_inode *inode, u32 value)
 187 {
 188         switch (UFS_SB(sb)->s_flags & UFS_UID_MASK) {
 189         case UFS_UID_EFT:
 190                 inode->ui_u3.ui_sun.ui_uid = cpu_to_fs32(sb, value);
 191                 break;
 192         case UFS_UID_44BSD:
 193                 inode->ui_u3.ui_44.ui_uid = cpu_to_fs32(sb, value);
 194                 break;
 195         }
 196         inode->ui_u1.oldids.ui_suid = cpu_to_fs16(sb, value);
 197 }
 198
 199 static inline u32
 200 ufs_get_inode_gid(struct super_block *sb, struct ufs_inode *inode)
 201 {
 202         switch (UFS_SB(sb)->s_flags & UFS_UID_MASK) {
 203         case UFS_UID_EFT:
 204                 return fs32_to_cpu(sb, inode->ui_u3.ui_sun.ui_gid);
 205         case UFS_UID_44BSD:
 206                 return fs32_to_cpu(sb, inode->ui_u3.ui_44.ui_gid);
 207         default:
 208                 return fs16_to_cpu(sb, inode->ui_u1.oldids.ui_sgid);
 209         }
 210 }
 211
 212 static inline void
 213 ufs_set_inode_gid(struct super_block *sb, struct ufs_inode *inode, u32 value)
 214 {
 215         switch (UFS_SB(sb)->s_flags & UFS_UID_MASK) {
 216         case UFS_UID_EFT:
 217                 inode->ui_u3.ui_sun.ui_gid = cpu_to_fs32(sb, value);
 218                 break;
 219         case UFS_UID_44BSD:
 220                 inode->ui_u3.ui_44.ui_gid = cpu_to_fs32(sb, value);
 221                 break;
 222         }
 223         inode->ui_u1.oldids.ui_sgid =  cpu_to_fs16(sb, value);
 224 }
 225
 226 extern dev_t ufs_get_inode_dev(struct super_block *, struct ufs_inode_info *);
 227 extern void ufs_set_inode_dev(struct super_block *, struct ufs_inode_info *, dev_t);
 228
 229 /*
 230  * These functions manipulate ufs buffers
 231  */
 232 #define ubh_bread(sb,fragment,size) _ubh_bread_(uspi,sb,fragment,size)
 233 extern struct ufs_buffer_head * _ubh_bread_(struct ufs_sb_private_info *, struct super_block *, u64 , u64);
 234 extern struct ufs_buffer_head * ubh_bread_uspi(struct ufs_sb_private_info *, struct super_block *, u64, u64);
 235 extern void ubh_brelse (struct ufs_buffer_head *);
 236 extern void ubh_brelse_uspi (struct ufs_sb_private_info *);
 237 extern void ubh_mark_buffer_dirty (struct ufs_buffer_head *);
 238 extern void ubh_mark_buffer_uptodate (struct ufs_buffer_head *, int);
 239 extern void ubh_ll_rw_block (int, unsigned, struct ufs_buffer_head **);
 240 extern void ubh_wait_on_buffer (struct ufs_buffer_head *);
 241 extern unsigned ubh_max_bcount (struct ufs_buffer_head *);
 242 extern void ubh_bforget (struct ufs_buffer_head *);
 243 extern int  ubh_buffer_dirty (struct ufs_buffer_head *);
 244 #define ubh_ubhcpymem(mem,ubh,size) _ubh_ubhcpymem_(uspi,mem,ubh,size)
 245 extern void _ubh_ubhcpymem_(struct ufs_sb_private_info *, unsigned char *, struct ufs_buffer_head *, unsigned);
 246 #define ubh_memcpyubh(ubh,mem,size) _ubh_memcpyubh_(uspi,ubh,mem,size)
 247 extern void _ubh_memcpyubh_(struct ufs_sb_private_info *, struct ufs_buffer_head *, unsigned char *, unsigned);
 248
 249
 250
 251 /*
 252  * macros to get important structures from ufs_buffer_head
 253  */
 254 #define ubh_get_usb_first(ubh) \
 255         ((struct ufs_super_block_first *)((ubh)->bh[0]->b_data))
 256
 257 #define ubh_get_usb_second(ubh) \
 258         ((struct ufs_super_block_second *)(ubh)-> \
 259         bh[UFS_SECTOR_SIZE >> uspi->s_fshift]->b_data + (UFS_SECTOR_SIZE & ~uspi->s_fmask))
 260
 261 #define ubh_get_usb_third(ubh) \
 262         ((struct ufs_super_block_third *)((ubh)-> \
 263         bh[UFS_SECTOR_SIZE*2 >> uspi->s_fshift]->b_data + (UFS_SECTOR_SIZE*2 & ~uspi->s_fmask)))
 264
 265 #define ubh_get_ucg(ubh) \
 266         ((struct ufs_cylinder_group *)((ubh)->bh[0]->b_data))
 267
 268
 269 /*
 270  * Extract byte from ufs_buffer_head
 271  * Extract the bits for a block from a map inside ufs_buffer_head
 272  */
 273 #define ubh_get_addr8(ubh,begin) \
 274         ((u8*)(ubh)->bh[(begin) >> uspi->s_fshift]->b_data + \
 275         ((begin) & ~uspi->s_fmask))
 276
 277 #define ubh_get_addr16(ubh,begin) \
 278         (((__fs16*)((ubh)->bh[(begin) >> (uspi->s_fshift-1)]->b_data)) + \
 279         ((begin) & (uspi->fsize>>1) - 1)))
 280
 281 #define ubh_get_addr32(ubh,begin) \
 282         (((__fs32*)((ubh)->bh[(begin) >> (uspi->s_fshift-2)]->b_data)) + \
 283         ((begin) & ((uspi->s_fsize>>2) - 1)))
 284
 285 #define ubh_get_addr ubh_get_addr8
 286
 287 #define ubh_blkmap(ubh,begin,bit) \
 288         ((*ubh_get_addr(ubh, (begin) + ((bit) >> 3)) >> ((bit) & 7)) & (0xff >> (UFS_MAXFRAG - uspi->s_fpb)))
 289
 290
 291 /*
 292  * Macros for access to superblock array structures
 293  */
 294 #define ubh_postbl(ubh,cylno,i) \
 295         ((uspi->s_postblformat != UFS_DYNAMICPOSTBLFMT) \
 296         ? (*(__s16*)(ubh_get_addr(ubh, \
 297         (unsigned)(&((struct ufs_super_block *)0)->fs_opostbl) \
 298         + (((cylno) * 16 + (i)) << 1) ) )) \
 299         : (*(__s16*)(ubh_get_addr(ubh, \
 300         uspi->s_postbloff + (((cylno) * uspi->s_nrpos + (i)) << 1) ))))
 301
 302 #define ubh_rotbl(ubh,i) \
 303         ((uspi->s_postblformat != UFS_DYNAMICPOSTBLFMT) \
 304         ? (*(__u8*)(ubh_get_addr(ubh, \
 305         (unsigned)(&((struct ufs_super_block *)0)->fs_space) + (i)))) \
 306         : (*(__u8*)(ubh_get_addr(ubh, uspi->s_rotbloff + (i)))))
 307
 308 /*
 309  * Determine the number of available frags given a
 310  * percentage to hold in reserve.
 311  */
 312 #define ufs_freespace(usb, percentreserved) \
 313         (ufs_blkstofrags(fs32_to_cpu(sb, (usb)->fs_cstotal.cs_nbfree)) + \
 314         fs32_to_cpu(sb, (usb)->fs_cstotal.cs_nffree) - (uspi->s_dsize * (percentreserved) / 100))
 315
 316 /*
 317  * Macros to access cylinder group array structures
 318  */
 319 #define ubh_cg_blktot(ucpi,cylno) \
 320         (*((__fs32*)ubh_get_addr(UCPI_UBH, (ucpi)->c_btotoff + ((cylno) << 2))))
 321
 322 #define ubh_cg_blks(ucpi,cylno,rpos) \
 323         (*((__fs16*)ubh_get_addr(UCPI_UBH, \
 324         (ucpi)->c_boff + (((cylno) * uspi->s_nrpos + (rpos)) << 1 ))))
 325
 326 /*
 327  * Bitmap operations
 328  * These functions work like classical bitmap operations.
 329  * The difference is that we don't have the whole bitmap
 330  * in one contiguous chunk of memory, but in several buffers.
 331  * The parameters of each function are super_block, ufs_buffer_head and
 332  * position of the beginning of the bitmap.
 333  */
 334 #define ubh_setbit(ubh,begin,bit) \
 335         (*ubh_get_addr(ubh, (begin) + ((bit) >> 3)) |= (1 << ((bit) & 7)))
 336
 337 #define ubh_clrbit(ubh,begin,bit) \
 338         (*ubh_get_addr (ubh, (begin) + ((bit) >> 3)) &= ~(1 << ((bit) & 7)))
 339
 340 #define ubh_isset(ubh,begin,bit) \
 341         (*ubh_get_addr (ubh, (begin) + ((bit) >> 3)) & (1 << ((bit) & 7)))
 342
 343 #define ubh_isclr(ubh,begin,bit) (!ubh_isset(ubh,begin,bit))
 344
 345 #define ubh_find_first_zero_bit(ubh,begin,size) _ubh_find_next_zero_bit_(uspi,ubh,begin,size,0)
 346
 347 #define ubh_find_next_zero_bit(ubh,begin,size,offset) _ubh_find_next_zero_bit_(uspi,ubh,begin,size,offset)
 348 static inline unsigned _ubh_find_next_zero_bit_(
 349         struct ufs_sb_private_info * uspi, struct ufs_buffer_head * ubh,
 350         unsigned begin, unsigned size, unsigned offset)
 351 {
 352         unsigned base, count, pos;
 353
 354         size -= offset;
 355         begin <<= 3;
 356         offset += begin;
 357         base = offset >> uspi->s_bpfshift;
 358         offset &= uspi->s_bpfmask;
 359         for (;;) {
 360                 count = min_t(unsigned int, size + offset, uspi->s_bpf);
 361                 size -= count - offset;
 362                 pos = ext2_find_next_zero_bit (ubh->bh[base]->b_data, count, offset);
 363                 if (pos < count || !size)
 364                         break;
 365                 base++;
 366                 offset = 0;
 367         }
 368         return (base << uspi->s_bpfshift) + pos - begin;
 369 }
 370
 371 static inline unsigned find_last_zero_bit (unsigned char * bitmap,
 372         unsigned size, unsigned offset)
 373 {
 374         unsigned bit, i;
 375         unsigned char * mapp;
 376         unsigned char map;
 377
 378         mapp = bitmap + (size >> 3);
 379         map = *mapp--;
 380         bit = 1 << (size & 7);
 381         for (i = size; i > offset; i--) {
 382                 if ((map & bit) == 0)
 383                         break;
 384                 if ((i & 7) != 0) {
 385                         bit >>= 1;
 386                 } else {
 387                         map = *mapp--;
 388                         bit = 1 << 7;
 389                 }
 390         }
 391         return i;
 392 }
 393
 394 #define ubh_find_last_zero_bit(ubh,begin,size,offset) _ubh_find_last_zero_bit_(uspi,ubh,begin,size,offset)
 395 static inline unsigned _ubh_find_last_zero_bit_(
 396         struct ufs_sb_private_info * uspi, struct ufs_buffer_head * ubh,
 397         unsigned begin, unsigned start, unsigned end)
 398 {
 399         unsigned base, count, pos, size;
 400
 401         size = start - end;
 402         begin <<= 3;
 403         start += begin;
 404         base = start >> uspi->s_bpfshift;
 405         start &= uspi->s_bpfmask;
 406         for (;;) {
 407                 count = min_t(unsigned int,
 408                             size + (uspi->s_bpf - start), uspi->s_bpf)
 409                         - (uspi->s_bpf - start);
 410                 size -= count;
 411                 pos = find_last_zero_bit (ubh->bh[base]->b_data,
 412                         start, start - count);
 413                 if (pos > start - count || !size)
 414                         break;
 415                 base--;
 416                 start = uspi->s_bpf;
 417         }
 418         return (base << uspi->s_bpfshift) + pos - begin;
 419 }
 420
 421 #define ubh_isblockclear(ubh,begin,block) (!_ubh_isblockset_(uspi,ubh,begin,block))
 422
 423 #define ubh_isblockset(ubh,begin,block) _ubh_isblockset_(uspi,ubh,begin,block)
 424 static inline int _ubh_isblockset_(struct ufs_sb_private_info * uspi,
 425         struct ufs_buffer_head * ubh, unsigned begin, unsigned block)
 426 {
 427         switch (uspi->s_fpb) {
 428         case 8:
 429                 return (*ubh_get_addr (ubh, begin + block) == 0xff);
 430         case 4:
 431                 return (*ubh_get_addr (ubh, begin + (block >> 1)) == (0x0f << ((block & 0x01) << 2)));
 432         case 2:
 433                 return (*ubh_get_addr (ubh, begin + (block >> 2)) == (0x03 << ((block & 0x03) << 1)));
 434         case 1:
 435                 return (*ubh_get_addr (ubh, begin + (block >> 3)) == (0x01 << (block & 0x07)));
 436         }
 437         return 0;
 438 }
 439
 440 #define ubh_clrblock(ubh,begin,block) _ubh_clrblock_(uspi,ubh,begin,block)
 441 static inline void _ubh_clrblock_(struct ufs_sb_private_info * uspi,
 442         struct ufs_buffer_head * ubh, unsigned begin, unsigned block)
 443 {
 444         switch (uspi->s_fpb) {
 445         case 8:
 446                 *ubh_get_addr (ubh, begin + block) = 0x00;
 447                 return;
 448         case 4:
 449                 *ubh_get_addr (ubh, begin + (block >> 1)) &= ~(0x0f << ((block & 0x01) << 2));
 450                 return;
 451         case 2:
 452                 *ubh_get_addr (ubh, begin + (block >> 2)) &= ~(0x03 << ((block & 0x03) << 1));
 453                 return;
 454         case 1:
 455                 *ubh_get_addr (ubh, begin + (block >> 3)) &= ~(0x01 << ((block & 0x07)));
 456                 return;
 457         }
 458 }
 459
 460 #define ubh_setblock(ubh,begin,block) _ubh_setblock_(uspi,ubh,begin,block)
 461 static inline void _ubh_setblock_(struct ufs_sb_private_info * uspi,
 462         struct ufs_buffer_head * ubh, unsigned begin, unsigned block)
 463 {
 464         switch (uspi->s_fpb) {
 465         case 8:
 466                 *ubh_get_addr(ubh, begin + block) = 0xff;
 467                 return;
 468         case 4:
 469                 *ubh_get_addr(ubh, begin + (block >> 1)) |= (0x0f << ((block & 0x01) << 2));
 470                 return;
 471         case 2:
 472                 *ubh_get_addr(ubh, begin + (block >> 2)) |= (0x03 << ((block & 0x03) << 1));
 473                 return;
 474         case 1:
 475                 *ubh_get_addr(ubh, begin + (block >> 3)) |= (0x01 << ((block & 0x07)));
 476                 return;
 477         }
 478 }
 479
 480 static inline void ufs_fragacct (struct super_block * sb, unsigned blockmap,
 481         __fs32 * fraglist, int cnt)
 482 {
 483         struct ufs_sb_private_info * uspi;
 484         unsigned fragsize, pos;
 485
 486         uspi = UFS_SB(sb)->s_uspi;
 487
 488         fragsize = 0;
 489         for (pos = 0; pos < uspi->s_fpb; pos++) {
 490                 if (blockmap & (1 << pos)) {
 491                         fragsize++;
 492                 }
 493                 else if (fragsize > 0) {
 494                         fs32_add(sb, &fraglist[fragsize], cnt);
 495                         fragsize = 0;
 496                 }
 497         }
 498         if (fragsize > 0 && fragsize < uspi->s_fpb)
 499                 fs32_add(sb, &fraglist[fragsize], cnt);
 500 }
 501
 502 #define ubh_scanc(ubh,begin,size,table,mask) _ubh_scanc_(uspi,ubh,begin,size,table,mask)
 503 static inline unsigned _ubh_scanc_(struct ufs_sb_private_info * uspi, struct ufs_buffer_head * ubh,
 504         unsigned begin, unsigned size, unsigned char * table, unsigned char mask)
 505 {
 506         unsigned rest, offset;
 507         unsigned char * cp;
 508
 509
 510         offset = begin & ~uspi->s_fmask;
 511         begin >>= uspi->s_fshift;
 512         for (;;) {
 513                 if ((offset + size) < uspi->s_fsize)
 514                         rest = size;
 515                 else
 516                         rest = uspi->s_fsize - offset;
 517                 size -= rest;
 518                 cp = ubh->bh[begin]->b_data + offset;
 519                 while ((table[*cp++] & mask) == 0 && --rest);
 520                 if (rest || !size)
 521                         break;
 522                 begin++;
 523                 offset = 0;
 524         }
 525         return (size + rest);
 526 }