void buddy_free_range(buddy_t *bd, range_t range)
{
unsigned i;
uint64_t old_start, start;
uintptr_t sz, min_sz;
min_sz = 1 << MIN_BUDDY_SZ_LOG2;
if (aligned_for(range.start, MIN_BUDDY_SZ_LOG2) == 0) {
if (range.extent < min_sz) {
return;
}
old_start = range.start;
range.start &= ~0ULL << MIN_BUDDY_SZ_LOG2;
range.start += min_sz;
range.extent -= range.start - old_start;
}
while (range.extent >= min_sz &&
aligned_for(range.start, MIN_BUDDY_SZ_LOG2)) {
for(i = MAX_BUDDY_SZ_LOG2; i >= MIN_BUDDY_SZ_LOG2; i--) {
sz = 1 << i;
start = range.start - bd->start;
if (sz > range.extent || aligned_for(start, i) == 0) {
continue;
}
range.extent -= sz;
range.start += sz;
buddy_free(bd, start + bd->start, sz);
break;
}
}
}
void buddy_free_range(buddy_t *bd, range_t range) {
uintptr_t min_sz = 1 << MIN_BUDDY_SZ_LOG2;
/** Firstly, we use a helper function to check if the range's start address
is aligned to a multiple of the smallest block size. If not, we adjust
it so that it is. { */
/* Ensure the range start address is at least aligned to
MIN_BUDDY_SZ_LOG2. */
if (aligned_for(range.start, MIN_BUDDY_SZ_LOG2) == 0) {
if (range.extent < min_sz)
return;
uint64_t old_start = range.start;
range.start &= ~0ULL << MIN_BUDDY_SZ_LOG2;
range.start += min_sz;
range.extent -= range.start - old_start;
}
/** Now, we iteratively work through the range trying to allocate the largest
block we can. { */
while (range.extent >= min_sz &&
aligned_for(range.start, MIN_BUDDY_SZ_LOG2)) {
for (unsigned i = MAX_BUDDY_SZ_LOG2; i >= MIN_BUDDY_SZ_LOG2; --i) {
uintptr_t sz = 1 << i;
uint64_t start = range.start - bd->start;
if (sz > range.extent || aligned_for(start, i) == 0)
continue;
range.extent -= sz;
range.start += sz;
buddy_free(bd, start + bd->start, sz);
break;
}
}
}
