|
@@ -1,109 +0,0 @@
|
|
|
-#ifndef CONFIG_GENERIC_FIND_FIRST_BIT
|
|
|
-#include <linux/bitops.h>
|
|
|
-
|
|
|
-#undef find_first_zero_bit
|
|
|
-#undef find_first_bit
|
|
|
-
|
|
|
-static inline long
|
|
|
-__find_first_zero_bit(const unsigned long * addr, unsigned long size)
|
|
|
-{
|
|
|
- long d0, d1, d2;
|
|
|
- long res;
|
|
|
-
|
|
|
- /*
|
|
|
- * We must test the size in words, not in bits, because
|
|
|
- * otherwise incoming sizes in the range -63..-1 will not run
|
|
|
- * any scasq instructions, and then the flags used by the je
|
|
|
- * instruction will have whatever random value was in place
|
|
|
- * before. Nobody should call us like that, but
|
|
|
- * find_next_zero_bit() does when offset and size are at the
|
|
|
- * same word and it fails to find a zero itself.
|
|
|
- */
|
|
|
- size += 63;
|
|
|
- size >>= 6;
|
|
|
- if (!size)
|
|
|
- return 0;
|
|
|
- asm volatile(
|
|
|
- " repe; scasq\n"
|
|
|
- " je 1f\n"
|
|
|
- " xorq -8(%%rdi),%%rax\n"
|
|
|
- " subq $8,%%rdi\n"
|
|
|
- " bsfq %%rax,%%rdx\n"
|
|
|
- "1: subq %[addr],%%rdi\n"
|
|
|
- " shlq $3,%%rdi\n"
|
|
|
- " addq %%rdi,%%rdx"
|
|
|
- :"=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2)
|
|
|
- :"0" (0ULL), "1" (size), "2" (addr), "3" (-1ULL),
|
|
|
- [addr] "S" (addr) : "memory");
|
|
|
- /*
|
|
|
- * Any register would do for [addr] above, but GCC tends to
|
|
|
- * prefer rbx over rsi, even though rsi is readily available
|
|
|
- * and doesn't have to be saved.
|
|
|
- */
|
|
|
- return res;
|
|
|
-}
|
|
|
-
|
|
|
-/**
|
|
|
- * 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.
|
|
|
- */
|
|
|
-long find_first_zero_bit(const unsigned long * addr, unsigned long size)
|
|
|
-{
|
|
|
- return __find_first_zero_bit (addr, size);
|
|
|
-}
|
|
|
-
|
|
|
-static inline long
|
|
|
-__find_first_bit(const unsigned long * addr, unsigned long size)
|
|
|
-{
|
|
|
- long d0, d1;
|
|
|
- long res;
|
|
|
-
|
|
|
- /*
|
|
|
- * We must test the size in words, not in bits, because
|
|
|
- * otherwise incoming sizes in the range -63..-1 will not run
|
|
|
- * any scasq instructions, and then the flags used by the jz
|
|
|
- * instruction will have whatever random value was in place
|
|
|
- * before. Nobody should call us like that, but
|
|
|
- * find_next_bit() does when offset and size are at the same
|
|
|
- * word and it fails to find a one itself.
|
|
|
- */
|
|
|
- size += 63;
|
|
|
- size >>= 6;
|
|
|
- if (!size)
|
|
|
- return 0;
|
|
|
- asm volatile(
|
|
|
- " repe; scasq\n"
|
|
|
- " jz 1f\n"
|
|
|
- " subq $8,%%rdi\n"
|
|
|
- " bsfq (%%rdi),%%rax\n"
|
|
|
- "1: subq %[addr],%%rdi\n"
|
|
|
- " shlq $3,%%rdi\n"
|
|
|
- " addq %%rdi,%%rax"
|
|
|
- :"=a" (res), "=&c" (d0), "=&D" (d1)
|
|
|
- :"0" (0ULL), "1" (size), "2" (addr),
|
|
|
- [addr] "r" (addr) : "memory");
|
|
|
- return res;
|
|
|
-}
|
|
|
-
|
|
|
-/**
|
|
|
- * find_first_bit - find the first set 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 set bit, not the number of the byte
|
|
|
- * containing a bit.
|
|
|
- */
|
|
|
-long find_first_bit(const unsigned long * addr, unsigned long size)
|
|
|
-{
|
|
|
- return __find_first_bit(addr,size);
|
|
|
-}
|
|
|
-
|
|
|
-#include <linux/module.h>
|
|
|
-
|
|
|
-EXPORT_SYMBOL(find_first_bit);
|
|
|
-EXPORT_SYMBOL(find_first_zero_bit);
|
|
|
-#endif
|