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Diffstat (limited to 'arch/x86/lib/bitops_64.c')
-rw-r--r--arch/x86/lib/bitops_64.c175
1 files changed, 0 insertions, 175 deletions
diff --git a/arch/x86/lib/bitops_64.c b/arch/x86/lib/bitops_64.c
deleted file mode 100644
index 0e8f491e6cc..00000000000
--- a/arch/x86/lib/bitops_64.c
+++ /dev/null
@@ -1,175 +0,0 @@
-#include <linux/bitops.h>
-
-#undef find_first_zero_bit
-#undef find_next_zero_bit
-#undef find_first_bit
-#undef find_next_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);
-}
-
-/**
- * find_next_zero_bit - find the next 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
- */
-long find_next_zero_bit (const unsigned long * addr, long size, long offset)
-{
- const unsigned long * p = addr + (offset >> 6);
- unsigned long set = 0;
- unsigned long res, bit = offset&63;
-
- if (bit) {
- /*
- * Look for zero in first word
- */
- asm("bsfq %1,%0\n\t"
- "cmoveq %2,%0"
- : "=r" (set)
- : "r" (~(*p >> bit)), "r"(64L));
- if (set < (64 - bit))
- return set + offset;
- set = 64 - bit;
- p++;
- }
- /*
- * No zero yet, search remaining full words for a zero
- */
- res = __find_first_zero_bit (p, size - 64 * (p - addr));
-
- return (offset + set + res);
-}
-
-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);
-}
-
-/**
- * find_next_bit - find the first set 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
- */
-long find_next_bit(const unsigned long * addr, long size, long offset)
-{
- const unsigned long * p = addr + (offset >> 6);
- unsigned long set = 0, bit = offset & 63, res;
-
- if (bit) {
- /*
- * Look for nonzero in the first 64 bits:
- */
- asm("bsfq %1,%0\n\t"
- "cmoveq %2,%0\n\t"
- : "=r" (set)
- : "r" (*p >> bit), "r" (64L));
- if (set < (64 - bit))
- return set + offset;
- set = 64 - bit;
- p++;
- }
- /*
- * No set bit yet, search remaining full words for a bit
- */
- res = __find_first_bit (p, size - 64 * (p - addr));
- return (offset + set + res);
-}
-
-#include <linux/module.h>
-
-EXPORT_SYMBOL(find_next_bit);
-EXPORT_SYMBOL(find_first_bit);
-EXPORT_SYMBOL(find_first_zero_bit);
-EXPORT_SYMBOL(find_next_zero_bit);