1 #include <linux/kernel.h>
3 #include <asm/cputype.h>
4 #include <asm/pgalloc.h>
5 #include <asm/pgtable.h>
7 static void idmap_add_pmd(pgd_t *pgd, unsigned long addr, unsigned long end,
10 pmd_t *pmd = pmd_offset(pgd, addr);
12 addr = (addr & PMD_MASK) | prot;
19 void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
21 unsigned long prot, next;
23 prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE;
24 if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
27 pgd += pgd_index(addr);
29 next = pgd_addr_end(addr, end);
30 idmap_add_pmd(pgd, addr, next, prot);
31 } while (pgd++, addr = next, addr != end);
35 static void idmap_del_pmd(pgd_t *pgd, unsigned long addr, unsigned long end)
37 pmd_t *pmd = pmd_offset(pgd, addr);
41 void identity_mapping_del(pgd_t *pgd, unsigned long addr, unsigned long end)
45 pgd += pgd_index(addr);
47 next = pgd_addr_end(addr, end);
48 idmap_del_pmd(pgd, addr, next);
49 } while (pgd++, addr = next, addr != end);
54 * In order to soft-boot, we need to insert a 1:1 mapping in place of
55 * the user-mode pages. This will then ensure that we have predictable
56 * results when turning the mmu off
58 void setup_mm_for_reboot(char mode)
61 * We need to access to user-mode page tables here. For kernel threads
62 * we don't have any user-mode mappings so we use the context that we
65 identity_mapping_add(current->active_mm->pgd, 0, TASK_SIZE);
66 local_flush_tlb_all();