void __ref vmemmap_free(unsigned long start, unsigned long end,
struct vmem_altmap *altmap)
{
unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
unsigned long page_order = get_order(page_size);
unsigned long alt_start = ~0, alt_end = ~0;
unsigned long base_pfn;
start = _ALIGN_DOWN(start, page_size);
if (altmap) {
alt_start = altmap->base_pfn;
alt_end = altmap->base_pfn + altmap->reserve +
altmap->free + altmap->alloc + altmap->align;
}
pr_debug("vmemmap_free %lx...%lx\n", start, end);
for (; start < end; start += page_size) {
unsigned long nr_pages, addr;
struct page *section_base;
struct page *page;
/*
* the section has already be marked as invalid, so
* vmemmap_populated() true means some other sections still
* in this page, so skip it.
*/
if (vmemmap_populated(start, page_size))
continue;
addr = vmemmap_list_free(start);
if (!addr)
continue;
page = pfn_to_page(addr >> PAGE_SHIFT);
section_base = pfn_to_page(vmemmap_section_start(start));
nr_pages = 1 << page_order;
base_pfn = PHYS_PFN(addr);
if (base_pfn >= alt_start && base_pfn < alt_end) {
vmem_altmap_free(altmap, nr_pages);
} else if (PageReserved(page)) {
/* allocated from bootmem */
if (page_size < PAGE_SIZE) {
/*
* this shouldn't happen, but if it is
* the case, leave the memory there
*/
WARN_ON_ONCE(1);
} else {
while (nr_pages--)
free_reserved_page(page++);
}
} else {
free_pages((unsigned long)(__va(addr)), page_order);
}
vmemmap_remove_mapping(start, page_size);
}
}
/*
* Check if this vmemmap page is already initialised. If any section
* which overlaps this vmemmap page is initialised then this page is
* initialised already.
*/
static int __meminit vmemmap_populated(unsigned long start, int page_size)
{
unsigned long end = start + page_size;
start = (unsigned long)(pfn_to_page(vmemmap_section_start(start)));
for (; start < end; start += (PAGES_PER_SECTION * sizeof(struct page)))
if (pfn_valid(page_to_pfn((struct page *)start)))
return 1;
return 0;
}
