BITMAP_FIND_FREE_REG(9) Basic Kernel Library Functions BITMAP_FIND_FREE_REG(9)

NAME bitmap_find_free_region - find a contiguous aligned mem region

SYNOPSIS int bitmap_find_free_region(unsigned long * bitmap, int bits, int order);

ARGUMENTS bitmap array of unsigned longs corresponding to the bitmap

bits number of bits in the bitmap

order region size (log base 2 of number of bits) to find

DESCRIPTION Find a region of free (zero) bits in a bitmap of bits bits and allocate them (set them to one). Only consider regions of length a power (order) of two, aligned to that power of two, which makes the search algorithm much faster.

Return the bit offset in bitmap of the allocated region, or -errno on failure.

COPYRIGHT Kernel Hackers Manual 2.6. July 2015 BITMAP_FIND_FREE_REG(9)