diff options
Diffstat (limited to 'include/linux/find.h')
| -rw-r--r-- | include/linux/find.h | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/include/linux/find.h b/include/linux/find.h index ccaf61a0f5fd..4647864a5ffd 100644 --- a/include/linux/find.h +++ b/include/linux/find.h @@ -22,6 +22,9 @@ unsigned long __find_nth_and_bit(const unsigned long *addr1, const unsigned long unsigned long size, unsigned long n); unsigned long __find_nth_andnot_bit(const unsigned long *addr1, const unsigned long *addr2, unsigned long size, unsigned long n); +unsigned long __find_nth_and_andnot_bit(const unsigned long *addr1, const unsigned long *addr2, + const unsigned long *addr3, unsigned long size, + unsigned long n); extern unsigned long _find_first_and_bit(const unsigned long *addr1, const unsigned long *addr2, unsigned long size); extern unsigned long _find_first_zero_bit(const unsigned long *addr, unsigned long size); @@ -255,6 +258,36 @@ unsigned long find_nth_andnot_bit(const unsigned long *addr1, const unsigned lon return __find_nth_andnot_bit(addr1, addr2, size, n); } +/** + * find_nth_and_andnot_bit - find N'th set bit in 2 memory regions, + * excluding those set in 3rd region + * @addr1: The 1st address to start the search at + * @addr2: The 2nd address to start the search at + * @addr3: The 3rd address to start the search at + * @size: The maximum number of bits to search + * @n: The number of set bit, which position is needed, counting from 0 + * + * Returns the bit number of the N'th set bit. + * If no such, returns @size. + */ +static __always_inline +unsigned long find_nth_and_andnot_bit(const unsigned long *addr1, + const unsigned long *addr2, + const unsigned long *addr3, + unsigned long size, unsigned long n) +{ + if (n >= size) + return size; + + if (small_const_nbits(size)) { + unsigned long val = *addr1 & *addr2 & (~*addr3) & GENMASK(size - 1, 0); + + return val ? fns(val, n) : size; + } + + return __find_nth_and_andnot_bit(addr1, addr2, addr3, size, n); +} + #ifndef find_first_and_bit /** * find_first_and_bit - find the first set bit in both memory regions |