static int findbit(int low, int startscan, int pages, int memflags, int *len)
{
int run_length = 0, i;
int freerange_start = startscan;
for(i = startscan; i >= low; i--) {
if(!page_isfree(i)) {
int pi;
int chunk = i/BITCHUNK_BITS, moved = 0;
run_length = 0;
pi = i;
while(chunk > 0 &&
!MAP_CHUNK(free_pages_bitmap, chunk*BITCHUNK_BITS)) {
chunk--;
moved = 1;
}
if(moved) { i = chunk * BITCHUNK_BITS + BITCHUNK_BITS; }
continue;
}
if(!run_length) { freerange_start = i; run_length = 1; }
else { freerange_start--; run_length++; }
assert(run_length <= pages);
if(run_length == pages) {
/* good block found! */
*len = run_length;
return freerange_start;
}
}
return NO_MEM;
}
void set_bit_sized(unsigned char *bitmap, uint16_t size, uint16_t bit)
{
(MAP_CHUNK(bitmap, size, bit)) |= (1 << CHUNK_OFFSET(bit));
}
void set_bit(bitmap_t *bm, uint16_t bit)
{
(MAP_CHUNK(*bm, bit)) |= (1 << CHUNK_OFFSET(bit));
}
void unset_bit(bitmap_t *bm, uint16_t bit)
{
((MAP_CHUNK(*bm, bit)) &= ~(1 << CHUNK_OFFSET(bit)));
}
int is_bit_set(const bitmap_t *bm, uint16_t bit)
{
return (MAP_CHUNK(*bm, bit) & (1 << CHUNK_OFFSET(bit))) != 0;
}
