1 #include <linux/kernel.h>
2
3 #include <asm/cputype.h>
4 #include <asm/pgalloc.h>
5 #include <asm/pgtable.h>
6
idmap_add_pmd(pud_t * pud,unsigned long addr,unsigned long end,unsigned long prot)7 static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end,
8 unsigned long prot)
9 {
10 pmd_t *pmd = pmd_offset(pud, addr);
11
12 addr = (addr & PMD_MASK) | prot;
13 pmd[0] = __pmd(addr);
14 addr += SECTION_SIZE;
15 pmd[1] = __pmd(addr);
16 flush_pmd_entry(pmd);
17 }
18
idmap_add_pud(pgd_t * pgd,unsigned long addr,unsigned long end,unsigned long prot)19 static void idmap_add_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
20 unsigned long prot)
21 {
22 pud_t *pud = pud_offset(pgd, addr);
23 unsigned long next;
24
25 do {
26 next = pud_addr_end(addr, end);
27 idmap_add_pmd(pud, addr, next, prot);
28 } while (pud++, addr = next, addr != end);
29 }
30
identity_mapping_add(pgd_t * pgd,unsigned long addr,unsigned long end)31 void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
32 {
33 unsigned long prot, next;
34
35 prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE;
36 if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
37 prot |= PMD_BIT4;
38
39 pgd += pgd_index(addr);
40 do {
41 next = pgd_addr_end(addr, end);
42 idmap_add_pud(pgd, addr, next, prot);
43 } while (pgd++, addr = next, addr != end);
44 }
45
46 #ifdef CONFIG_SMP
idmap_del_pmd(pud_t * pud,unsigned long addr,unsigned long end)47 static void idmap_del_pmd(pud_t *pud, unsigned long addr, unsigned long end)
48 {
49 pmd_t *pmd = pmd_offset(pud, addr);
50 pmd_clear(pmd);
51 }
52
idmap_del_pud(pgd_t * pgd,unsigned long addr,unsigned long end)53 static void idmap_del_pud(pgd_t *pgd, unsigned long addr, unsigned long end)
54 {
55 pud_t *pud = pud_offset(pgd, addr);
56 unsigned long next;
57
58 do {
59 next = pud_addr_end(addr, end);
60 idmap_del_pmd(pud, addr, next);
61 } while (pud++, addr = next, addr != end);
62 }
63
identity_mapping_del(pgd_t * pgd,unsigned long addr,unsigned long end)64 void identity_mapping_del(pgd_t *pgd, unsigned long addr, unsigned long end)
65 {
66 unsigned long next;
67
68 pgd += pgd_index(addr);
69 do {
70 next = pgd_addr_end(addr, end);
71 idmap_del_pud(pgd, addr, next);
72 } while (pgd++, addr = next, addr != end);
73 }
74 #endif
75
76 /*
77 * In order to soft-boot, we need to insert a 1:1 mapping in place of
78 * the user-mode pages. This will then ensure that we have predictable
79 * results when turning the mmu off
80 */
setup_mm_for_reboot(char mode)81 void setup_mm_for_reboot(char mode)
82 {
83 /*
84 * We need to access to user-mode page tables here. For kernel threads
85 * we don't have any user-mode mappings so we use the context that we
86 * "borrowed".
87 */
88 identity_mapping_add(current->active_mm->pgd, 0, TASK_SIZE);
89 local_flush_tlb_all();
90 }
91