linux-imx

// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright (c) 2000-2005 Silicon Graphics, Inc.

 * All Rights Reserved.

 */

#include "xfs.h"

#include "xfs_log_format.h"

#include "xfs_bit.h"

​

/*

 * XFS bit manipulation routines, used in non-realtime code.

 */

​

/*

 * Return whether bitmap is empty.

 * Size is number of words in the bitmap, which is padded to word boundary

 * Returns 1 for empty, 0 for non-empty.

 */

int

xfs_bitmap_empty(uint *map, uint size)

{

    uint i;

​

    for (i = 0; i < size; i++) {

        if (map[i] != 0)

            return 0;

    }

​

    return 1;

}

​

/*

 * Count the number of contiguous bits set in the bitmap starting with bit

 * start_bit.  Size is the size of the bitmap in words.

 */

int

xfs_contig_bits(uint *map, uint size, uint start_bit)

{

    uint * p = ((unsigned int *) map) + (start_bit >> BIT_TO_WORD_SHIFT);

    uint result = 0;

    uint tmp;

​

    size <<= BIT_TO_WORD_SHIFT;

​

    ASSERT(start_bit < size);

    size -= start_bit & ~(NBWORD - 1);

    start_bit &= (NBWORD - 1);

    if (start_bit) {

        tmp = *p++;

        /* set to one first offset bits prior to start */

        tmp |= (~0U >> (NBWORD-start_bit));

        if (tmp != ~0U)

            goto found;

        result += NBWORD;

        size -= NBWORD;

    }

    while (size) {

        if ((tmp = *p++) != ~0U)

            goto found;

        result += NBWORD;

        size -= NBWORD;

    }

    return result - start_bit;