ARM: pgtable: use conventional page table code for identity mappings
Remove some knowledge of our 2-level page table layout from the
identity mapping code - we assume that a step size of PGDIR_SIZE will
allow us to step over all entries. While this is true today, it won't
be true in the near future.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c
index 034124d..5729944 100644
--- a/arch/arm/mm/idmap.c
+++ b/arch/arm/mm/idmap.c
@@ -4,33 +4,49 @@
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
+static void idmap_add_pmd(pgd_t *pgd, unsigned long addr, unsigned long end,
+ unsigned long prot)
+{
+ pmd_t *pmd = pmd_offset(pgd, addr);
+
+ addr = (addr & PMD_MASK) | prot;
+ pmd[0] = __pmd(addr);
+ addr += SECTION_SIZE;
+ pmd[1] = __pmd(addr);
+ flush_pmd_entry(pmd);
+}
+
void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
{
- unsigned long prot;
+ unsigned long prot, next;
prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE;
if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
prot |= PMD_BIT4;
- for (addr &= PGDIR_MASK; addr < end;) {
- pmd_t *pmd = pmd_offset(pgd + pgd_index(addr), addr);
- pmd[0] = __pmd(addr | prot);
- addr += SECTION_SIZE;
- pmd[1] = __pmd(addr | prot);
- addr += SECTION_SIZE;
- flush_pmd_entry(pmd);
- }
+ pgd += pgd_index(addr);
+ do {
+ next = pgd_addr_end(addr, end);
+ idmap_add_pmd(pgd, addr, next, prot);
+ } while (pgd++, addr = next, addr != end);
}
#ifdef CONFIG_SMP
+static void idmap_del_pmd(pgd_t *pgd, unsigned long addr, unsigned long end)
+{
+ pmd_t *pmd = pmd_offset(pgd, addr);
+ pmd_clear(pmd);
+}
+
void identity_mapping_del(pgd_t *pgd, unsigned long addr, unsigned long end)
{
- for (addr &= PGDIR_MASK; addr < end; addr += PGDIR_SIZE) {
- pmd_t *pmd = pmd_offset(pgd + pgd_index(addr), addr);
- pmd[0] = __pmd(0);
- pmd[1] = __pmd(0);
- clean_pmd_entry(pmd);
- }
+ unsigned long next;
+
+ pgd += pgd_index(addr);
+ do {
+ next = pgd_addr_end(addr, end);
+ idmap_del_pmd(pgd, addr, next);
+ } while (pgd++, addr = next, addr != end);
}
#endif