ARM: pgtable: collect up identity mapping functions
We have two places where we create identity mappings - one when we bring
secondary CPUs online, and one where we setup some mappings for soft-
reboot. Combine these two into a single implementation. Also collect
the identity mapping deletion function.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index e582214..1e31af2 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -474,6 +474,9 @@
#define pgtable_cache_init() do { } while (0)
+void identity_mapping_add(pgd_t *, unsigned long, unsigned long);
+void identity_mapping_del(pgd_t *, unsigned long, unsigned long);
+
#endif /* !__ASSEMBLY__ */
#endif /* CONFIG_MMU */
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 4631380..73cef40 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -68,40 +68,6 @@
IPI_CPU_STOP,
};
-static inline void identity_mapping_add(pgd_t *pgd, unsigned long start,
- unsigned long end)
-{
- unsigned long addr, prot;
- pmd_t *pmd;
-
- prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE;
- if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
- prot |= PMD_BIT4;
-
- for (addr = start & PGDIR_MASK; addr < end;) {
- 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);
- }
-}
-
-static inline void identity_mapping_del(pgd_t *pgd, unsigned long start,
- unsigned long end)
-{
- unsigned long addr;
- pmd_t *pmd;
-
- for (addr = start & PGDIR_MASK; addr < end; addr += PGDIR_SIZE) {
- pmd = pmd_offset(pgd + pgd_index(addr), addr);
- pmd[0] = __pmd(0);
- pmd[1] = __pmd(0);
- clean_pmd_entry(pmd);
- }
-}
-
int __cpuinit __cpu_up(unsigned int cpu)
{
struct cpuinfo_arm *ci = &per_cpu(cpu_data, cpu);
diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile
index d63b6c4..00d74a0 100644
--- a/arch/arm/mm/Makefile
+++ b/arch/arm/mm/Makefile
@@ -5,8 +5,8 @@
obj-y := dma-mapping.o extable.o fault.o init.o \
iomap.o
-obj-$(CONFIG_MMU) += fault-armv.o flush.o ioremap.o mmap.o \
- pgd.o mmu.o vmregion.o
+obj-$(CONFIG_MMU) += fault-armv.o flush.o idmap.o ioremap.o \
+ mmap.o pgd.o mmu.o vmregion.o
ifneq ($(CONFIG_MMU),y)
obj-y += nommu.o
diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c
new file mode 100644
index 0000000..034124d
--- /dev/null
+++ b/arch/arm/mm/idmap.c
@@ -0,0 +1,51 @@
+#include <linux/kernel.h>
+
+#include <asm/cputype.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+
+void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
+{
+ unsigned long prot;
+
+ 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);
+ }
+}
+
+#ifdef CONFIG_SMP
+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);
+ }
+}
+#endif
+
+/*
+ * In order to soft-boot, we need to insert a 1:1 mapping in place of
+ * the user-mode pages. This will then ensure that we have predictable
+ * results when turning the mmu off
+ */
+void setup_mm_for_reboot(char mode)
+{
+ /*
+ * We need to access to user-mode page tables here. For kernel threads
+ * we don't have any user-mode mappings so we use the context that we
+ * "borrowed".
+ */
+ identity_mapping_add(current->active_mm->pgd, 0, TASK_SIZE);
+ local_flush_tlb_all();
+}
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 94ee093..bd1a11e 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -1045,38 +1045,3 @@
empty_zero_page = virt_to_page(zero_page);
__flush_dcache_page(NULL, empty_zero_page);
}
-
-/*
- * In order to soft-boot, we need to insert a 1:1 mapping in place of
- * the user-mode pages. This will then ensure that we have predictable
- * results when turning the mmu off
- */
-void setup_mm_for_reboot(char mode)
-{
- unsigned long base_pmdval;
- pgd_t *pgd;
- int i;
-
- /*
- * We need to access to user-mode page tables here. For kernel threads
- * we don't have any user-mode mappings so we use the context that we
- * "borrowed".
- */
- pgd = current->active_mm->pgd;
-
- base_pmdval = PMD_SECT_AP_WRITE | PMD_SECT_AP_READ | PMD_TYPE_SECT;
- if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
- base_pmdval |= PMD_BIT4;
-
- for (i = 0; i < FIRST_USER_PGD_NR + USER_PTRS_PER_PGD; i++, pgd++) {
- unsigned long pmdval = (i << PGDIR_SHIFT) | base_pmdval;
- pmd_t *pmd;
-
- pmd = pmd_off(pgd, i << PGDIR_SHIFT);
- pmd[0] = __pmd(pmdval);
- pmd[1] = __pmd(pmdval + (1 << (PGDIR_SHIFT - 1)));
- flush_pmd_entry(pmd);
- }
-
- local_flush_tlb_all();
-}