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- /* SPDX-License-Identifier: GPL-2.0 */
- /*
- * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
- * All Rights Reserved.
- */
- #ifndef __XFS_BIT_H__
- #define __XFS_BIT_H__
- /*
- * XFS bit manipulation routines.
- */
- /*
- * masks with n high/low bits set, 64-bit values
- */
- static inline uint64_t xfs_mask64hi(int n)
- {
- return (uint64_t)-1 << (64 - (n));
- }
- static inline uint32_t xfs_mask32lo(int n)
- {
- return ((uint32_t)1 << (n)) - 1;
- }
- static inline uint64_t xfs_mask64lo(int n)
- {
- return ((uint64_t)1 << (n)) - 1;
- }
- /* Get high bit set out of 32-bit argument, -1 if none set */
- static inline int xfs_highbit32(uint32_t v)
- {
- return fls(v) - 1;
- }
- /* Get high bit set out of 64-bit argument, -1 if none set */
- static inline int xfs_highbit64(uint64_t v)
- {
- return fls64(v) - 1;
- }
- /* Get low bit set out of 32-bit argument, -1 if none set */
- static inline int xfs_lowbit32(uint32_t v)
- {
- return ffs(v) - 1;
- }
- /* Get low bit set out of 64-bit argument, -1 if none set */
- static inline int xfs_lowbit64(uint64_t v)
- {
- uint32_t w = (uint32_t)v;
- int n = 0;
- if (w) { /* lower bits */
- n = ffs(w);
- } else { /* upper bits */
- w = (uint32_t)(v >> 32);
- if (w) {
- n = ffs(w);
- if (n)
- n += 32;
- }
- }
- return n - 1;
- }
- /* Return whether bitmap is empty (1 == empty) */
- extern int xfs_bitmap_empty(uint *map, uint size);
- /* Count continuous one bits in map starting with start_bit */
- extern int xfs_contig_bits(uint *map, uint size, uint start_bit);
- /* Find next set bit in map */
- extern int xfs_next_bit(uint *map, uint size, uint start_bit);
- #endif /* __XFS_BIT_H__ */
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