static void free_pages(void *p, size_t len)
{
LOGICALLY_FREEING_PAGES(len);
free_actual_pages(p, len, 0);
}
/* the VM subsystem as defined by the GC files */
static void *do_malloc_pages(size_t len, size_t alignment, int dirty_ok)
{
kern_return_t retval;
size_t extra = 0;
void *r;
if(!task_self) task_self = mach_task_self();
CHECK_USED_AGAINST_MAX(len);
/* round up to the nearest page: */
if(len & (page_size - 1))
len += page_size - (len & (page_size - 1));
r = find_cached_pages(len, alignment, dirty_ok);
if (r)
return r;
extra = alignment;
retval = vm_allocate(task_self, (vm_address_t*)&r, len + extra, TRUE);
if(retval != KERN_SUCCESS) {
GCPRINT(GCOUTF, "Couldn't allocate memory: %s\n", mach_error_string(retval));
abort();
}
if(extra) {
/* we allocated too large so we can choose the alignment */
void *real_r;
long pre_extra;
real_r = (void*)(((unsigned long)r + (alignment-1)) & (~(alignment-1)));
pre_extra = real_r - r;
if(pre_extra) {
retval = vm_deallocate(task_self, (vm_address_t)r, pre_extra);
if(retval != KERN_SUCCESS) {
GCPRINT(GCOUTF, "WARNING: couldn't deallocate pre-extra: %s\n",
mach_error_string(retval));
}
}
if(pre_extra < extra) {
if (!pre_extra) {
/* Instead of actually unmapping, put it in the cache, and there's
a good chance we can use it next time: */
ACTUALLY_ALLOCATING_PAGES(extra);
free_actual_pages(real_r + len, extra, 1);
} else {
retval = vm_deallocate(task_self, (vm_address_t)real_r + len,
extra - pre_extra);
if(retval != KERN_SUCCESS) {
GCPRINT(GCOUTF, "WARNING: couldn't deallocate post-extra: %s\n",
mach_error_string(retval));
}
}
}
r = real_r;
}
ACTUALLY_ALLOCATING_PAGES(len);
LOGICALLY_ALLOCATING_PAGES(len);
return r;
}
