bitops.h revision 271a375b596240866b4a2967e3b6f38ff7cecdf8
1/* 2 * bitops.h --- Bitmap frobbing code. The byte swapping routines are 3 * also included here. 4 * 5 * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o. 6 * 7 * %Begin-Header% 8 * This file may be redistributed under the terms of the GNU Public 9 * License. 10 * %End-Header% 11 * 12 * i386 bitops operations taken from <asm/bitops.h>, Copyright 1992, 13 * Linus Torvalds. 14 */ 15 16 17extern int ext2fs_set_bit(unsigned int nr,void * addr); 18extern int ext2fs_clear_bit(unsigned int nr, void * addr); 19extern int ext2fs_test_bit(unsigned int nr, const void * addr); 20extern void ext2fs_fast_set_bit(unsigned int nr,void * addr); 21extern void ext2fs_fast_clear_bit(unsigned int nr, void * addr); 22extern __u16 ext2fs_swab16(__u16 val); 23extern __u32 ext2fs_swab32(__u32 val); 24extern __u64 ext2fs_swab64(__u64 val); 25 26#ifdef WORDS_BIGENDIAN 27#define ext2fs_cpu_to_le64(x) ext2fs_swab64((x)) 28#define ext2fs_le64_to_cpu(x) ext2fs_swab64((x)) 29#define ext2fs_cpu_to_le32(x) ext2fs_swab32((x)) 30#define ext2fs_le32_to_cpu(x) ext2fs_swab32((x)) 31#define ext2fs_cpu_to_le16(x) ext2fs_swab16((x)) 32#define ext2fs_le16_to_cpu(x) ext2fs_swab16((x)) 33#define ext2fs_cpu_to_be32(x) ((__u32)(x)) 34#define ext2fs_be32_to_cpu(x) ((__u32)(x)) 35#define ext2fs_cpu_to_be16(x) ((__u16)(x)) 36#define ext2fs_be16_to_cpu(x) ((__u16)(x)) 37#else 38#define ext2fs_cpu_to_le64(x) ((__u64)(x)) 39#define ext2fs_le64_to_cpu(x) ((__u64)(x)) 40#define ext2fs_cpu_to_le32(x) ((__u32)(x)) 41#define ext2fs_le32_to_cpu(x) ((__u32)(x)) 42#define ext2fs_cpu_to_le16(x) ((__u16)(x)) 43#define ext2fs_le16_to_cpu(x) ((__u16)(x)) 44#define ext2fs_cpu_to_be32(x) ext2fs_swab32((x)) 45#define ext2fs_be32_to_cpu(x) ext2fs_swab32((x)) 46#define ext2fs_cpu_to_be16(x) ext2fs_swab16((x)) 47#define ext2fs_be16_to_cpu(x) ext2fs_swab16((x)) 48#endif 49 50/* 51 * EXT2FS bitmap manipulation routines. 52 */ 53 54/* Support for sending warning messages from the inline subroutines */ 55extern const char *ext2fs_block_string; 56extern const char *ext2fs_inode_string; 57extern const char *ext2fs_mark_string; 58extern const char *ext2fs_unmark_string; 59extern const char *ext2fs_test_string; 60extern void ext2fs_warn_bitmap(errcode_t errcode, unsigned long arg, 61 const char *description); 62extern void ext2fs_warn_bitmap2(ext2fs_generic_bitmap bitmap, 63 int code, unsigned long arg); 64 65extern int ext2fs_mark_block_bitmap(ext2fs_block_bitmap bitmap, blk_t block); 66extern int ext2fs_unmark_block_bitmap(ext2fs_block_bitmap bitmap, 67 blk_t block); 68extern int ext2fs_test_block_bitmap(ext2fs_block_bitmap bitmap, blk_t block); 69 70extern int ext2fs_mark_inode_bitmap(ext2fs_inode_bitmap bitmap, ext2_ino_t inode); 71extern int ext2fs_unmark_inode_bitmap(ext2fs_inode_bitmap bitmap, 72 ext2_ino_t inode); 73extern int ext2fs_test_inode_bitmap(ext2fs_inode_bitmap bitmap, ext2_ino_t inode); 74 75extern void ext2fs_fast_mark_block_bitmap(ext2fs_block_bitmap bitmap, 76 blk_t block); 77extern void ext2fs_fast_unmark_block_bitmap(ext2fs_block_bitmap bitmap, 78 blk_t block); 79extern int ext2fs_fast_test_block_bitmap(ext2fs_block_bitmap bitmap, 80 blk_t block); 81 82extern void ext2fs_fast_mark_inode_bitmap(ext2fs_inode_bitmap bitmap, 83 ext2_ino_t inode); 84extern void ext2fs_fast_unmark_inode_bitmap(ext2fs_inode_bitmap bitmap, 85 ext2_ino_t inode); 86extern int ext2fs_fast_test_inode_bitmap(ext2fs_inode_bitmap bitmap, 87 ext2_ino_t inode); 88extern blk_t ext2fs_get_block_bitmap_start(ext2fs_block_bitmap bitmap); 89extern ext2_ino_t ext2fs_get_inode_bitmap_start(ext2fs_inode_bitmap bitmap); 90extern blk_t ext2fs_get_block_bitmap_end(ext2fs_block_bitmap bitmap); 91extern ext2_ino_t ext2fs_get_inode_bitmap_end(ext2fs_inode_bitmap bitmap); 92 93extern void ext2fs_mark_block_bitmap_range(ext2fs_block_bitmap bitmap, 94 blk_t block, int num); 95extern void ext2fs_unmark_block_bitmap_range(ext2fs_block_bitmap bitmap, 96 blk_t block, int num); 97extern int ext2fs_test_block_bitmap_range(ext2fs_block_bitmap bitmap, 98 blk_t block, int num); 99extern void ext2fs_fast_mark_block_bitmap_range(ext2fs_block_bitmap bitmap, 100 blk_t block, int num); 101extern void ext2fs_fast_unmark_block_bitmap_range(ext2fs_block_bitmap bitmap, 102 blk_t block, int num); 103extern int ext2fs_fast_test_block_bitmap_range(ext2fs_block_bitmap bitmap, 104 blk_t block, int num); 105extern void ext2fs_set_bitmap_padding(ext2fs_generic_bitmap map); 106 107/* These routines moved to gen_bitmap.c */ 108extern int ext2fs_mark_generic_bitmap(ext2fs_generic_bitmap bitmap, 109 __u32 bitno); 110extern int ext2fs_unmark_generic_bitmap(ext2fs_generic_bitmap bitmap, 111 blk_t bitno); 112extern int ext2fs_test_generic_bitmap(ext2fs_generic_bitmap bitmap, 113 blk_t bitno); 114extern int ext2fs_test_block_bitmap_range(ext2fs_block_bitmap bitmap, 115 blk_t block, int num); 116extern __u32 ext2fs_get_generic_bitmap_start(ext2fs_generic_bitmap bitmap); 117extern __u32 ext2fs_get_generic_bitmap_end(ext2fs_generic_bitmap bitmap); 118 119/* 120 * The inline routines themselves... 121 * 122 * If NO_INLINE_FUNCS is defined, then we won't try to do inline 123 * functions at all; they will be included as normal functions in 124 * inline.c 125 */ 126#ifdef NO_INLINE_FUNCS 127#if (defined(__GNUC__) && (defined(__i386__) || defined(__i486__) || \ 128 defined(__i586__) || defined(__mc68000__))) 129 /* This prevents bitops.c from trying to include the C */ 130 /* function version of these functions */ 131#define _EXT2_HAVE_ASM_BITOPS_ 132#endif 133#endif /* NO_INLINE_FUNCS */ 134 135#if (defined(INCLUDE_INLINE_FUNCS) || !defined(NO_INLINE_FUNCS)) 136#ifdef INCLUDE_INLINE_FUNCS 137#define _INLINE_ extern 138#else 139#ifdef __GNUC__ 140#define _INLINE_ extern __inline__ 141#else /* For Watcom C */ 142#define _INLINE_ extern inline 143#endif 144#endif 145 146/* 147 * Fast bit set/clear functions that doesn't need to return the 148 * previous bit value. 149 */ 150 151_INLINE_ void ext2fs_fast_set_bit(unsigned int nr,void * addr) 152{ 153 unsigned char *ADDR = (unsigned char *) addr; 154 155 ADDR += nr >> 3; 156 *ADDR |= (1 << (nr & 0x07)); 157} 158 159_INLINE_ void ext2fs_fast_clear_bit(unsigned int nr, void * addr) 160{ 161 unsigned char *ADDR = (unsigned char *) addr; 162 163 ADDR += nr >> 3; 164 *ADDR &= ~(1 << (nr & 0x07)); 165} 166 167 168#if ((defined __GNUC__) && !defined(_EXT2_USE_C_VERSIONS_) && \ 169 (defined(__i386__) || defined(__i486__) || defined(__i586__))) 170 171#define _EXT2_HAVE_ASM_BITOPS_ 172#define _EXT2_HAVE_ASM_SWAB_ 173#define _EXT2_HAVE_ASM_FINDBIT_ 174 175/* 176 * These are done by inline assembly for speed reasons..... 177 * 178 * All bitoperations return 0 if the bit was cleared before the 179 * operation and != 0 if it was not. Bit 0 is the LSB of addr; bit 32 180 * is the LSB of (addr+1). 181 */ 182 183/* 184 * Some hacks to defeat gcc over-optimizations.. 185 */ 186struct __dummy_h { unsigned long a[100]; }; 187#define EXT2FS_ADDR (*(struct __dummy_h *) addr) 188#define EXT2FS_CONST_ADDR (*(const struct __dummy_h *) addr) 189 190_INLINE_ int ext2fs_set_bit(unsigned int nr, void * addr) 191{ 192 int oldbit; 193 194 addr = (void *) (((unsigned char *) addr) + (nr >> 3)); 195 __asm__ __volatile__("btsl %2,%1\n\tsbbl %0,%0" 196 :"=r" (oldbit),"+m" (EXT2FS_ADDR) 197 :"r" (nr & 7)); 198 return oldbit; 199} 200 201_INLINE_ int ext2fs_clear_bit(unsigned int nr, void * addr) 202{ 203 int oldbit; 204 205 addr = (void *) (((unsigned char *) addr) + (nr >> 3)); 206 __asm__ __volatile__("btrl %2,%1\n\tsbbl %0,%0" 207 :"=r" (oldbit),"+m" (EXT2FS_ADDR) 208 :"r" (nr & 7)); 209 return oldbit; 210} 211 212_INLINE_ int ext2fs_test_bit(unsigned int nr, const void * addr) 213{ 214 int oldbit; 215 216 addr = (const void *) (((const unsigned char *) addr) + (nr >> 3)); 217 __asm__ __volatile__("btl %2,%1\n\tsbbl %0,%0" 218 :"=r" (oldbit) 219 :"m" (EXT2FS_CONST_ADDR),"r" (nr & 7)); 220 return oldbit; 221} 222 223#if 0 224_INLINE_ int ext2fs_find_first_bit_set(void * addr, unsigned size) 225{ 226 int d0, d1, d2; 227 int res; 228 229 if (!size) 230 return 0; 231 /* This looks at memory. Mark it volatile to tell gcc not to move it around */ 232 __asm__ __volatile__( 233 "cld\n\t" 234 "xorl %%eax,%%eax\n\t" 235 "xorl %%edx,%%edx\n\t" 236 "repe; scasl\n\t" 237 "je 1f\n\t" 238 "movl -4(%%edi),%%eax\n\t" 239 "subl $4,%%edi\n\t" 240 "bsfl %%eax,%%edx\n" 241 "1:\tsubl %%esi,%%edi\n\t" 242 "shll $3,%%edi\n\t" 243 "addl %%edi,%%edx" 244 :"=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2) 245 :"1" ((size + 31) >> 5), "2" (addr), "S" (addr)); 246 return res; 247} 248 249_INLINE_ int ext2fs_find_next_bit_set (void * addr, int size, int offset) 250{ 251 unsigned long * p = ((unsigned long *) addr) + (offset >> 5); 252 int set = 0, bit = offset & 31, res; 253 254 if (bit) { 255 /* 256 * Look for zero in first byte 257 */ 258 __asm__("bsfl %1,%0\n\t" 259 "jne 1f\n\t" 260 "movl $32, %0\n" 261 "1:" 262 : "=r" (set) 263 : "r" (*p >> bit)); 264 if (set < (32 - bit)) 265 return set + offset; 266 set = 32 - bit; 267 p++; 268 } 269 /* 270 * No bit found yet, search remaining full bytes for a bit 271 */ 272 res = ext2fs_find_first_bit_set(p, size - 32 * (p - (unsigned long *) addr)); 273 return (offset + set + res); 274} 275#endif 276 277#ifdef EXT2FS_ENABLE_SWAPFS 278_INLINE_ __u32 ext2fs_swab32(__u32 val) 279{ 280#ifdef EXT2FS_REQUIRE_486 281 __asm__("bswap %0" : "=r" (val) : "0" (val)); 282#else 283 __asm__("xchgb %b0,%h0\n\t" /* swap lower bytes */ 284 "rorl $16,%0\n\t" /* swap words */ 285 "xchgb %b0,%h0" /* swap higher bytes */ 286 :"=q" (val) 287 : "0" (val)); 288#endif 289 return val; 290} 291 292_INLINE_ __u16 ext2fs_swab16(__u16 val) 293{ 294 __asm__("xchgb %b0,%h0" /* swap bytes */ \ 295 : "=q" (val) \ 296 : "0" (val)); \ 297 return val; 298} 299 300_INLINE_ __u64 ext2fs_swab64(__u64 val) 301{ 302 return (ext2fs_swab32(val >> 32) | 303 (((__u64)ext2fs_swab32(val & 0xFFFFFFFFUL)) << 32)); 304} 305#endif 306 307#undef EXT2FS_ADDR 308 309#endif /* i386 */ 310 311#if ((defined __GNUC__) && !defined(_EXT2_USE_C_VERSIONS_) && \ 312 (defined(__mc68000__))) 313 314#define _EXT2_HAVE_ASM_BITOPS_ 315 316_INLINE_ int ext2fs_set_bit(unsigned int nr,void * addr) 317{ 318 char retval; 319 320 __asm__ __volatile__ ("bfset %2@{%1:#1}; sne %0" 321 : "=d" (retval) : "d" (nr^7), "a" (addr)); 322 323 return retval; 324} 325 326_INLINE_ int ext2fs_clear_bit(unsigned int nr, void * addr) 327{ 328 char retval; 329 330 __asm__ __volatile__ ("bfclr %2@{%1:#1}; sne %0" 331 : "=d" (retval) : "d" (nr^7), "a" (addr)); 332 333 return retval; 334} 335 336_INLINE_ int ext2fs_test_bit(unsigned int nr, const void * addr) 337{ 338 char retval; 339 340 __asm__ __volatile__ ("bftst %2@{%1:#1}; sne %0" 341 : "=d" (retval) : "d" (nr^7), "a" (addr)); 342 343 return retval; 344} 345 346#endif /* __mc68000__ */ 347 348 349#if !defined(_EXT2_HAVE_ASM_SWAB_) && defined(EXT2FS_ENABLE_SWAPFS) 350 351_INLINE_ __u16 ext2fs_swab16(__u16 val) 352{ 353 return (val >> 8) | (val << 8); 354} 355 356_INLINE_ __u32 ext2fs_swab32(__u32 val) 357{ 358 return ((val>>24) | ((val>>8)&0xFF00) | 359 ((val<<8)&0xFF0000) | (val<<24)); 360} 361 362#endif /* !_EXT2_HAVE_ASM_SWAB */ 363 364#if !defined(_EXT2_HAVE_ASM_FINDBIT_) 365_INLINE_ int ext2fs_find_first_bit_set(void * addr, unsigned size) 366{ 367 char *cp = (char *) addr; 368 int res = 0, d0; 369 370 if (!size) 371 return 0; 372 373 while ((size > res) && (*cp == 0)) { 374 cp++; 375 res += 8; 376 } 377 d0 = ffs(*cp); 378 if (d0 == 0) 379 return size; 380 381 return res + d0 - 1; 382} 383 384_INLINE_ int ext2fs_find_next_bit_set (void * addr, int size, int offset) 385{ 386 unsigned char * p; 387 int set = 0, bit = offset & 7, res = 0, d0; 388 389 res = offset >> 3; 390 p = ((unsigned char *) addr) + res; 391 392 if (bit) { 393 set = ffs(*p & ~((1 << bit) - 1)); 394 if (set) 395 return (offset & ~7) + set - 1; 396 p++; 397 res += 8; 398 } 399 while ((size > res) && (*p == 0)) { 400 p++; 401 res += 8; 402 } 403 d0 = ffs(*p); 404 if (d0 == 0) 405 return size; 406 407 return (res + d0 - 1); 408} 409#endif 410 411_INLINE_ int ext2fs_mark_block_bitmap(ext2fs_block_bitmap bitmap, 412 blk_t block) 413{ 414 return ext2fs_mark_generic_bitmap((ext2fs_generic_bitmap) bitmap, 415 block); 416} 417 418_INLINE_ int ext2fs_unmark_block_bitmap(ext2fs_block_bitmap bitmap, 419 blk_t block) 420{ 421 return ext2fs_unmark_generic_bitmap((ext2fs_generic_bitmap) bitmap, 422 block); 423} 424 425_INLINE_ int ext2fs_test_block_bitmap(ext2fs_block_bitmap bitmap, 426 blk_t block) 427{ 428 return ext2fs_test_generic_bitmap((ext2fs_generic_bitmap) bitmap, 429 block); 430} 431 432_INLINE_ int ext2fs_mark_inode_bitmap(ext2fs_inode_bitmap bitmap, 433 ext2_ino_t inode) 434{ 435 return ext2fs_mark_generic_bitmap((ext2fs_generic_bitmap) bitmap, 436 inode); 437} 438 439_INLINE_ int ext2fs_unmark_inode_bitmap(ext2fs_inode_bitmap bitmap, 440 ext2_ino_t inode) 441{ 442 return ext2fs_unmark_generic_bitmap((ext2fs_generic_bitmap) bitmap, 443 inode); 444} 445 446_INLINE_ int ext2fs_test_inode_bitmap(ext2fs_inode_bitmap bitmap, 447 ext2_ino_t inode) 448{ 449 return ext2fs_test_generic_bitmap((ext2fs_generic_bitmap) bitmap, 450 inode); 451} 452 453_INLINE_ void ext2fs_fast_mark_block_bitmap(ext2fs_block_bitmap bitmap, 454 blk_t block) 455{ 456 ext2fs_mark_generic_bitmap((ext2fs_generic_bitmap) bitmap, block); 457} 458 459_INLINE_ void ext2fs_fast_unmark_block_bitmap(ext2fs_block_bitmap bitmap, 460 blk_t block) 461{ 462 ext2fs_unmark_generic_bitmap((ext2fs_generic_bitmap) bitmap, block); 463} 464 465_INLINE_ int ext2fs_fast_test_block_bitmap(ext2fs_block_bitmap bitmap, 466 blk_t block) 467{ 468 return ext2fs_test_generic_bitmap((ext2fs_generic_bitmap) bitmap, 469 block); 470} 471 472_INLINE_ void ext2fs_fast_mark_inode_bitmap(ext2fs_inode_bitmap bitmap, 473 ext2_ino_t inode) 474{ 475 ext2fs_mark_generic_bitmap((ext2fs_generic_bitmap) bitmap, inode); 476} 477 478_INLINE_ void ext2fs_fast_unmark_inode_bitmap(ext2fs_inode_bitmap bitmap, 479 ext2_ino_t inode) 480{ 481 ext2fs_unmark_generic_bitmap((ext2fs_generic_bitmap) bitmap, inode); 482} 483 484_INLINE_ int ext2fs_fast_test_inode_bitmap(ext2fs_inode_bitmap bitmap, 485 ext2_ino_t inode) 486{ 487 return ext2fs_test_generic_bitmap((ext2fs_generic_bitmap) bitmap, 488 inode); 489} 490 491_INLINE_ blk_t ext2fs_get_block_bitmap_start(ext2fs_block_bitmap bitmap) 492{ 493 return ext2fs_get_generic_bitmap_start((ext2fs_generic_bitmap) bitmap); 494} 495 496_INLINE_ ext2_ino_t ext2fs_get_inode_bitmap_start(ext2fs_inode_bitmap bitmap) 497{ 498 return ext2fs_get_generic_bitmap_start((ext2fs_generic_bitmap) bitmap); 499} 500 501_INLINE_ blk_t ext2fs_get_block_bitmap_end(ext2fs_block_bitmap bitmap) 502{ 503 return ext2fs_get_generic_bitmap_end((ext2fs_generic_bitmap) bitmap); 504} 505 506_INLINE_ ext2_ino_t ext2fs_get_inode_bitmap_end(ext2fs_inode_bitmap bitmap) 507{ 508 return ext2fs_get_generic_bitmap_end((ext2fs_generic_bitmap) bitmap); 509} 510 511_INLINE_ int ext2fs_fast_test_block_bitmap_range(ext2fs_block_bitmap bitmap, 512 blk_t block, int num) 513{ 514 return ext2fs_test_block_bitmap_range(bitmap, block, num); 515} 516 517_INLINE_ void ext2fs_fast_mark_block_bitmap_range(ext2fs_block_bitmap bitmap, 518 blk_t block, int num) 519{ 520 ext2fs_mark_block_bitmap_range(bitmap, block, num); 521} 522 523_INLINE_ void ext2fs_fast_unmark_block_bitmap_range(ext2fs_block_bitmap bitmap, 524 blk_t block, int num) 525{ 526 ext2fs_unmark_block_bitmap_range(bitmap, block, num); 527} 528#undef _INLINE_ 529#endif 530 531