static void __init setup_vm_final()

in mm/init.c [699:759]

• 43 lines of code
• 6 McCabe index (conditional complexity)

static void __init setup_vm_final(void)
{
	uintptr_t va, map_size;
	phys_addr_t pa, start, end;
	u64 i;

	/**
	 * MMU is enabled at this point. But page table setup is not complete yet.
	 * fixmap page table alloc functions should be used at this point
	 */
	pt_ops.alloc_pte = alloc_pte_fixmap;
	pt_ops.get_pte_virt = get_pte_virt_fixmap;
#ifndef __PAGETABLE_PMD_FOLDED
	pt_ops.alloc_pmd = alloc_pmd_fixmap;
	pt_ops.get_pmd_virt = get_pmd_virt_fixmap;
#endif
	/* Setup swapper PGD for fixmap */
	create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
			   __pa_symbol(fixmap_pgd_next),
			   PGDIR_SIZE, PAGE_TABLE);

	/* Map all memory banks in the linear mapping */
	for_each_mem_range(i, &start, &end) {
		if (start >= end)
			break;
		if (start <= __pa(PAGE_OFFSET) &&
		    __pa(PAGE_OFFSET) < end)
			start = __pa(PAGE_OFFSET);
		if (end >= __pa(PAGE_OFFSET) + memory_limit)
			end = __pa(PAGE_OFFSET) + memory_limit;

		map_size = best_map_size(start, end - start);
		for (pa = start; pa < end; pa += map_size) {
			va = (uintptr_t)__va(pa);

			create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
					   pgprot_from_va(va));
		}
	}

#ifdef CONFIG_64BIT
	/* Map the kernel */
	create_kernel_page_table(swapper_pg_dir, false);
#endif

	/* Clear fixmap PTE and PMD mappings */
	clear_fixmap(FIX_PTE);
	clear_fixmap(FIX_PMD);

	/* Move to swapper page table */
	csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | SATP_MODE);
	local_flush_tlb_all();

	/* generic page allocation functions must be used to setup page table */
	pt_ops.alloc_pte = alloc_pte_late;
	pt_ops.get_pte_virt = get_pte_virt_late;
#ifndef __PAGETABLE_PMD_FOLDED
	pt_ops.alloc_pmd = alloc_pmd_late;
	pt_ops.get_pmd_virt = get_pmd_virt_late;
#endif
}