From 614dd0585f376a25c638abbed9c5fbd21d7baece Mon Sep 17 00:00:00 2001 From: Russell King Date: Sun, 21 Nov 2010 11:41:57 +0000 Subject: 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 --- arch/arm/mm/Makefile | 4 ++-- arch/arm/mm/idmap.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ arch/arm/mm/mmu.c | 35 ----------------------------------- 3 files changed, 53 insertions(+), 37 deletions(-) create mode 100644 arch/arm/mm/idmap.c (limited to 'arch/arm/mm') 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 + +#include +#include +#include + +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 @@ void __init paging_init(struct machine_desc *mdesc) 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(); -} -- cgit v1.1