int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
{
unsigned long pfn, text;
- efi_memory_desc_t *md;
struct page *page;
unsigned npages;
pgd_t *pgd;
if (!IS_ENABLED(CONFIG_EFI_MIXED))
return 0;
- /*
- * Map all of RAM so that we can access arguments in the 1:1
- * mapping when making EFI runtime calls.
- */
- for_each_efi_memory_desc(md) {
- if (md->type != EFI_CONVENTIONAL_MEMORY &&
- md->type != EFI_LOADER_DATA &&
- md->type != EFI_LOADER_CODE)
- continue;
-
- pfn = md->phys_addr >> PAGE_SHIFT;
- npages = md->num_pages;
-
- if (kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, npages, _PAGE_RW)) {
- pr_err("Failed to map 1:1 memory\n");
- return 1;
- }
- }
-
page = alloc_page(GFP_KERNEL|__GFP_DMA32);
if (!page)
panic("Unable to allocate EFI runtime stack < 4GB\n");