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Kill off xfs_count_bits

xfs_count_bits is only called once, and is then compared to 0.
IOW, what it really wants to know is, is the bitmap empty.
This can be done more simply, certainly.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Merge of xfs-linux-melb:xfs-kern:28944a by kenmcd.

  xfs_count_bits is not really used to count bits, just to
  determine if the bitmap is empty or not. Replace it with
  a function that does just that.

/*
 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef __XFS_BIT_H__
#define	__XFS_BIT_H__

/*
 * XFS bit manipulation routines.
 */

/*
 * masks with n high/low bits set, 32-bit values & 64-bit values
 */
#define	XFS_MASK32HI(n)		xfs_mask32hi(n)
static inline __uint32_t xfs_mask32hi(int n)
{
	return (__uint32_t)-1 << (32 - (n));
}
#define	XFS_MASK64HI(n)		xfs_mask64hi(n)
static inline __uint64_t xfs_mask64hi(int n)
{
	return (__uint64_t)-1 << (64 - (n));
}
#define	XFS_MASK32LO(n)		xfs_mask32lo(n)
static inline __uint32_t xfs_mask32lo(int n)
{
	return ((__uint32_t)1 << (n)) - 1;
}
#define	XFS_MASK64LO(n)		xfs_mask64lo(n)
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 */
extern int xfs_highbit32(__uint32_t v);

/* Get low bit set out of 64-bit argument, -1 if none set */
extern int xfs_lowbit64(__uint64_t v);

/* Get high bit set out of 64-bit argument, -1 if none set */
extern int xfs_highbit64(__uint64_t);

/* 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__ */