Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 | /* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (c) 1994 - 1997, 1999, 2000 Ralf Baechle (ralf@gnu.org) * Copyright (c) 2000 Silicon Graphics, Inc. */ #ifndef _ASM_BITOPS_H #define _ASM_BITOPS_H #include <linux/types.h> #include <asm/byteorder.h> /* sigh ... */ #ifdef __KERNEL__ #include <asm/sgidefs.h> #include <asm/system.h> #include <linux/config.h> /* * clear_bit() doesn't provide any barrier for the compiler. */ #define smp_mb__before_clear_bit() barrier() #define smp_mb__after_clear_bit() barrier() /* * Only disable interrupt for kernel mode stuff to keep usermode stuff * that dares to use kernel include files alive. */ #define __bi_flags unsigned long flags #define __bi_cli() __cli() #define __bi_save_flags(x) __save_flags(x) #define __bi_save_and_cli(x) __save_and_cli(x) #define __bi_restore_flags(x) __restore_flags(x) #else #define __bi_flags #define __bi_cli() #define __bi_save_flags(x) #define __bi_save_and_cli(x) #define __bi_restore_flags(x) #endif /* __KERNEL__ */ #ifdef CONFIG_CPU_HAS_LLSC #include <asm/mipsregs.h> /* * These functions for MIPS ISA > 1 are interrupt and SMP proof and * interrupt friendly */ /* * set_bit - Atomically set a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * This function is atomic and may not be reordered. See __set_bit() * if you do not require the atomic guarantees. * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. */ extern __inline__ void set_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp; __asm__ __volatile__( "1:\tll\t%0, %1\t\t# set_bit\n\t" "or\t%0, %2\n\t" "sc\t%0, %1\n\t" "beqz\t%0, 1b" : "=&r" (temp), "=m" (*m) : "ir" (1UL << (nr & 0x1f)), "m" (*m)); } /* * __set_bit - Set a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * Unlike set_bit(), this function is non-atomic and may be reordered. * If it's called on the same region of memory simultaneously, the effect * may be that only one operation succeeds. */ extern __inline__ void __set_bit(int nr, volatile void * addr) { unsigned long * m = ((unsigned long *) addr) + (nr >> 5); *m |= 1UL << (nr & 31); } /* * clear_bit - Clears a bit in memory * @nr: Bit to clear * @addr: Address to start counting from * * clear_bit() is atomic and may not be reordered. However, it does * not contain a memory barrier, so if it is used for locking purposes, * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit() * in order to ensure changes are visible on other processors. */ extern __inline__ void clear_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp; __asm__ __volatile__( "1:\tll\t%0, %1\t\t# clear_bit\n\t" "and\t%0, %2\n\t" "sc\t%0, %1\n\t" "beqz\t%0, 1b\n\t" : "=&r" (temp), "=m" (*m) : "ir" (~(1UL << (nr & 0x1f))), "m" (*m)); } /* * change_bit - Toggle a bit in memory * @nr: Bit to clear * @addr: Address to start counting from * * change_bit() is atomic and may not be reordered. * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. */ extern __inline__ void change_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp; __asm__ __volatile__( "1:\tll\t%0, %1\t\t# change_bit\n\t" "xor\t%0, %2\n\t" "sc\t%0, %1\n\t" "beqz\t%0, 1b" : "=&r" (temp), "=m" (*m) : "ir" (1UL << (nr & 0x1f)), "m" (*m)); } /* * __change_bit - Toggle a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * Unlike change_bit(), this function is non-atomic and may be reordered. * If it's called on the same region of memory simultaneously, the effect * may be that only one operation succeeds. */ extern __inline__ void __change_bit(int nr, volatile void * addr) { unsigned long * m = ((unsigned long *) addr) + (nr >> 5); *m ^= 1UL << (nr & 31); } /* * test_and_set_bit - Set a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ extern __inline__ int test_and_set_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp, res; __asm__ __volatile__( ".set\tnoreorder\t\t# test_and_set_bit\n" "1:\tll\t%0, %1\n\t" "or\t%2, %0, %3\n\t" "sc\t%2, %1\n\t" "beqz\t%2, 1b\n\t" " and\t%2, %0, %3\n\t" ".set\treorder" : "=&r" (temp), "=m" (*m), "=&r" (res) : "r" (1UL << (nr & 0x1f)), "m" (*m) : "memory"); return res != 0; } /* * __test_and_set_bit - Set a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */ extern __inline__ int __test_and_set_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a |= mask; return retval; } /* * test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ extern __inline__ int test_and_clear_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp, res; __asm__ __volatile__( ".set\tnoreorder\t\t# test_and_clear_bit\n" "1:\tll\t%0, %1\n\t" "or\t%2, %0, %3\n\t" "xor\t%2, %3\n\t" "sc\t%2, %1\n\t" "beqz\t%2, 1b\n\t" " and\t%2, %0, %3\n\t" ".set\treorder" : "=&r" (temp), "=m" (*m), "=&r" (res) : "r" (1UL << (nr & 0x1f)), "m" (*m) : "memory"); return res != 0; } /* * __test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */ extern __inline__ int __test_and_clear_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a &= ~mask; return retval; } /* * test_and_change_bit - Change a bit and return its new value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ extern __inline__ int test_and_change_bit(int nr, volatile void *addr) { unsigned long *m = ((unsigned long *) addr) + (nr >> 5); unsigned long temp, res; __asm__ __volatile__( ".set\tnoreorder\t\t# test_and_change_bit\n" "1:\tll\t%0, %1\n\t" "xor\t%2, %0, %3\n\t" "sc\t%2, %1\n\t" "beqz\t%2, 1b\n\t" " and\t%2, %0, %3\n\t" ".set\treorder" : "=&r" (temp), "=m" (*m), "=&r" (res) : "r" (1UL << (nr & 0x1f)), "m" (*m) : "memory"); return res != 0; } /* * __test_and_change_bit - Change a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */ extern __inline__ int __test_and_change_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a ^= mask; return retval; } #else /* MIPS I */ /* * set_bit - Atomically set a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * This function is atomic and may not be reordered. See __set_bit() * if you do not require the atomic guarantees. * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. */ extern __inline__ void set_bit(int nr, volatile void * addr) { int mask; volatile int *a = addr; __bi_flags; a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); *a |= mask; __bi_restore_flags(flags); } /* * __set_bit - Set a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * Unlike set_bit(), this function is non-atomic and may be reordered. * If it's called on the same region of memory simultaneously, the effect * may be that only one operation succeeds. */ extern __inline__ void __set_bit(int nr, volatile void * addr) { int mask; volatile int *a = addr; a += nr >> 5; mask = 1 << (nr & 0x1f); *a |= mask; } /* * clear_bit - Clears a bit in memory * @nr: Bit to clear * @addr: Address to start counting from * * clear_bit() is atomic and may not be reordered. However, it does * not contain a memory barrier, so if it is used for locking purposes, * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit() * in order to ensure changes are visible on other processors. */ extern __inline__ void clear_bit(int nr, volatile void * addr) { int mask; volatile int *a = addr; __bi_flags; a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); *a &= ~mask; __bi_restore_flags(flags); } /* * change_bit - Toggle a bit in memory * @nr: Bit to clear * @addr: Address to start counting from * * change_bit() is atomic and may not be reordered. * Note that @nr may be almost arbitrarily large; this function is not * restricted to acting on a single-word quantity. */ extern __inline__ void change_bit(int nr, volatile void * addr) { int mask; volatile int *a = addr; __bi_flags; a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); *a ^= mask; __bi_restore_flags(flags); } /* * __change_bit - Toggle a bit in memory * @nr: the bit to set * @addr: the address to start counting from * * Unlike change_bit(), this function is non-atomic and may be reordered. * If it's called on the same region of memory simultaneously, the effect * may be that only one operation succeeds. */ extern __inline__ void __change_bit(int nr, volatile void * addr) { unsigned long * m = ((unsigned long *) addr) + (nr >> 5); *m ^= 1UL << (nr & 31); } /* * test_and_set_bit - Set a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ extern __inline__ int test_and_set_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; __bi_flags; a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); retval = (mask & *a) != 0; *a |= mask; __bi_restore_flags(flags); return retval; } /* * __test_and_set_bit - Set a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */ extern __inline__ int __test_and_set_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a |= mask; return retval; } /* * test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ extern __inline__ int test_and_clear_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; __bi_flags; a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); retval = (mask & *a) != 0; *a &= ~mask; __bi_restore_flags(flags); return retval; } /* * __test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */ extern __inline__ int __test_and_clear_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a &= ~mask; return retval; } /* * test_and_change_bit - Change a bit and return its new value * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and cannot be reordered. * It also implies a memory barrier. */ extern __inline__ int test_and_change_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; __bi_flags; a += nr >> 5; mask = 1 << (nr & 0x1f); __bi_save_and_cli(flags); retval = (mask & *a) != 0; *a ^= mask; __bi_restore_flags(flags); return retval; } /* * __test_and_change_bit - Change a bit and return its old value * @nr: Bit to set * @addr: Address to count from * * This operation is non-atomic and can be reordered. * If two examples of this operation race, one can appear to succeed * but actually fail. You must protect multiple accesses with a lock. */ extern __inline__ int __test_and_change_bit(int nr, volatile void * addr) { int mask, retval; volatile int *a = addr; a += nr >> 5; mask = 1 << (nr & 0x1f); retval = (mask & *a) != 0; *a ^= mask; return retval; } #undef __bi_flags #undef __bi_cli #undef __bi_save_flags #undef __bi_restore_flags #endif /* MIPS I */ /* * test_bit - Determine whether a bit is set * @nr: bit number to test * @addr: Address to start counting from */ extern __inline__ int test_bit(int nr, volatile void *addr) { return ((1UL << (nr & 31)) & (((const unsigned int *) addr)[nr >> 5])) != 0; } #ifndef __MIPSEB__ /* Little endian versions. */ /* * find_first_zero_bit - find the first zero bit in a memory region * @addr: The address to start the search at * @size: The maximum size to search * * Returns the bit-number of the first zero bit, not the number of the byte * containing a bit. */ extern __inline__ int find_first_zero_bit (void *addr, unsigned size) { unsigned long dummy; int res; if (!size) return 0; __asm__ (".set\tnoreorder\n\t" ".set\tnoat\n" "1:\tsubu\t$1,%6,%0\n\t" "blez\t$1,2f\n\t" "lw\t$1,(%5)\n\t" "addiu\t%5,4\n\t" #if (_MIPS_ISA == _MIPS_ISA_MIPS2 ) || (_MIPS_ISA == _MIPS_ISA_MIPS3 ) || \ (_MIPS_ISA == _MIPS_ISA_MIPS4 ) || (_MIPS_ISA == _MIPS_ISA_MIPS5 ) || \ (_MIPS_ISA == _MIPS_ISA_MIPS32) || (_MIPS_ISA == _MIPS_ISA_MIPS64) "beql\t%1,$1,1b\n\t" "addiu\t%0,32\n\t" #else "addiu\t%0,32\n\t" "beq\t%1,$1,1b\n\t" "nop\n\t" "subu\t%0,32\n\t" #endif #ifdef __MIPSEB__ #error "Fix this for big endian" #endif /* __MIPSEB__ */ "li\t%1,1\n" "1:\tand\t%2,$1,%1\n\t" "beqz\t%2,2f\n\t" "sll\t%1,%1,1\n\t" "bnez\t%1,1b\n\t" "add\t%0,%0,1\n\t" ".set\tat\n\t" ".set\treorder\n" "2:" : "=r" (res), "=r" (dummy), "=r" (addr) : "0" ((signed int) 0), "1" ((unsigned int) 0xffffffff), "2" (addr), "r" (size) : "$1"); return res; } /* * find_next_zero_bit - find the first zero bit in a memory region * @addr: The address to base the search on * @offset: The bitnumber to start searching at * @size: The maximum size to search */ extern __inline__ int find_next_zero_bit (void * addr, int size, int offset) { unsigned int *p = ((unsigned int *) addr) + (offset >> 5); int set = 0, bit = offset & 31, res; unsigned long dummy; if (bit) { /* * Look for zero in first byte */ #ifdef __MIPSEB__ #error "Fix this for big endian byte order" #endif __asm__(".set\tnoreorder\n\t" ".set\tnoat\n" "1:\tand\t$1,%4,%1\n\t" "beqz\t$1,1f\n\t" "sll\t%1,%1,1\n\t" "bnez\t%1,1b\n\t" "addiu\t%0,1\n\t" ".set\tat\n\t" ".set\treorder\n" "1:" : "=r" (set), "=r" (dummy) : "0" (0), "1" (1 << bit), "r" (*p) : "$1"); if (set < (32 - bit)) return set + offset; set = 32 - bit; p++; } /* * No zero yet, search remaining full bytes for a zero */ res = find_first_zero_bit(p, size - 32 * (p - (unsigned int *) addr)); return offset + set + res; } #endif /* !(__MIPSEB__) */ /* * ffz - find first zero in word. * @word: The word to search * * Undefined if no zero exists, so code should check against ~0UL first. */ extern __inline__ unsigned long ffz(unsigned long word) { unsigned int __res; unsigned int mask = 1; __asm__ ( ".set\tnoreorder\n\t" ".set\tnoat\n\t" "move\t%0,$0\n" "1:\tand\t$1,%2,%1\n\t" "beqz\t$1,2f\n\t" "sll\t%1,1\n\t" "bnez\t%1,1b\n\t" "addiu\t%0,1\n\t" ".set\tat\n\t" ".set\treorder\n" "2:\n\t" : "=&r" (__res), "=r" (mask) : "r" (word), "1" (mask) : "$1"); return __res; } #ifdef __KERNEL__ /** * ffs - find first bit set * @x: the word to search * * This is defined the same way as * the libc and compiler builtin ffs routines, therefore * differs in spirit from the above ffz (man ffs). */ #define ffs(x) generic_ffs(x) /* * hweightN - returns the hamming weight of a N-bit word * @x: the word to weigh * * The Hamming Weight of a number is the total number of bits set in it. */ #define hweight32(x) generic_hweight32(x) #define hweight16(x) generic_hweight16(x) #define hweight8(x) generic_hweight8(x) #endif /* __KERNEL__ */ #ifdef __MIPSEB__ /* * find_next_zero_bit - find the first zero bit in a memory region * @addr: The address to base the search on * @offset: The bitnumber to start searching at * @size: The maximum size to search */ extern __inline__ int find_next_zero_bit(void *addr, int size, int offset) { unsigned long *p = ((unsigned long *) addr) + (offset >> 5); unsigned long result = offset & ~31UL; unsigned long tmp; if (offset >= size) return size; size -= result; offset &= 31UL; if (offset) { tmp = *(p++); tmp |= ~0UL >> (32-offset); if (size < 32) goto found_first; if (~tmp) goto found_middle; size -= 32; result += 32; } while (size & ~31UL) { if (~(tmp = *(p++))) goto found_middle; result += 32; size -= 32; } if (!size) return result; tmp = *p; found_first: tmp |= ~0UL << size; found_middle: return result + ffz(tmp); } /* Linus sez that gcc can optimize the following correctly, we'll see if this * holds on the Sparc as it does for the ALPHA. */ #if 0 /* Fool kernel-doc since it doesn't do macros yet */ /* * find_first_zero_bit - find the first zero bit in a memory region * @addr: The address to start the search at * @size: The maximum size to search * * Returns the bit-number of the first zero bit, not the number of the byte * containing a bit. */ extern int find_first_zero_bit (void *addr, unsigned size); #endif #define find_first_zero_bit(addr, size) \ find_next_zero_bit((addr), (size), 0) #endif /* (__MIPSEB__) */ /* Now for the ext2 filesystem bit operations and helper routines. */ #ifdef __MIPSEB__ extern __inline__ int ext2_set_bit(int nr, void * addr) { int mask, retval, flags; unsigned char *ADDR = (unsigned char *) addr; ADDR += nr >> 3; mask = 1 << (nr & 0x07); save_and_cli(flags); retval = (mask & *ADDR) != 0; *ADDR |= mask; restore_flags(flags); return retval; } extern __inline__ int ext2_clear_bit(int nr, void * addr) { int mask, retval, flags; unsigned char *ADDR = (unsigned char *) addr; ADDR += nr >> 3; mask = 1 << (nr & 0x07); save_and_cli(flags); retval = (mask & *ADDR) != 0; *ADDR &= ~mask; restore_flags(flags); return retval; } extern __inline__ int ext2_test_bit(int nr, const void * addr) { int mask; const unsigned char *ADDR = (const unsigned char *) addr; ADDR += nr >> 3; mask = 1 << (nr & 0x07); return ((mask & *ADDR) != 0); } #define ext2_find_first_zero_bit(addr, size) \ ext2_find_next_zero_bit((addr), (size), 0) extern __inline__ unsigned long ext2_find_next_zero_bit(void *addr, unsigned long size, unsigned long offset) { unsigned long *p = ((unsigned long *) addr) + (offset >> 5); unsigned long result = offset & ~31UL; unsigned long tmp; if (offset >= size) return size; size -= result; offset &= 31UL; if(offset) { /* We hold the little endian value in tmp, but then the * shift is illegal. So we could keep a big endian value * in tmp, like this: * * tmp = __swab32(*(p++)); * tmp |= ~0UL >> (32-offset); * * but this would decrease preformance, so we change the * shift: */ tmp = *(p++); tmp |= __swab32(~0UL >> (32-offset)); if(size < 32) goto found_first; if(~tmp) goto found_middle; size -= 32; result += 32; } while(size & ~31UL) { if(~(tmp = *(p++))) goto found_middle; result += 32; size -= 32; } if(!size) return result; tmp = *p; found_first: /* tmp is little endian, so we would have to swab the shift, * see above. But then we have to swab tmp below for ffz, so * we might as well do this here. */ return result + ffz(__swab32(tmp) | (~0UL << size)); found_middle: return result + ffz(__swab32(tmp)); } #else /* !(__MIPSEB__) */ /* Native ext2 byte ordering, just collapse using defines. */ #define ext2_set_bit(nr, addr) test_and_set_bit((nr), (addr)) #define ext2_clear_bit(nr, addr) test_and_clear_bit((nr), (addr)) #define ext2_test_bit(nr, addr) test_bit((nr), (addr)) #define ext2_find_first_zero_bit(addr, size) find_first_zero_bit((addr), (size)) #define ext2_find_next_zero_bit(addr, size, offset) \ find_next_zero_bit((addr), (size), (offset)) #endif /* !(__MIPSEB__) */ /* * Bitmap functions for the minix filesystem. * FIXME: These assume that Minix uses the native byte/bitorder. * This limits the Minix filesystem's value for data exchange very much. */ #define minix_test_and_set_bit(nr,addr) test_and_set_bit(nr,addr) #define minix_set_bit(nr,addr) set_bit(nr,addr) #define minix_test_and_clear_bit(nr,addr) test_and_clear_bit(nr,addr) #define minix_test_bit(nr,addr) test_bit(nr,addr) #define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size) #endif /* _ASM_BITOPS_H */ |