From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ming Zhang <mingz@ele.uri.edu>
Subject: how to understand this bitmap_zero
Date: Wed, 09 Nov 2005 12:28:57 -0500
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could anybody help me on this? thanks!

see if we call bitmap_zero(dst, 2), it will do *dst = 0UL and thus clear
whole *dst, but what if we intent to clear 2 bits? not 32bits?

static inline void bitmap_zero(unsigned long *dst, int nbits)
{
        if (nbits <= BITS_PER_LONG)
                *dst = 0UL;
        else {
                int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
                memset(dst, 0, len);
        }
}


Ming