diff options
| -rw-r--r-- | arch/arm/include/asm/idmap.h | 17 | ||||
| -rw-r--r-- | arch/arm/include/asm/pgtable.h | 3 | ||||
| -rw-r--r-- | arch/arm/kernel/smp.c | 1 | ||||
| -rw-r--r-- | arch/arm/kernel/vmlinux.lds.S | 7 | ||||
| -rw-r--r-- | arch/arm/mm/idmap.c | 26 |
5 files changed, 51 insertions, 3 deletions
diff --git a/arch/arm/include/asm/idmap.h b/arch/arm/include/asm/idmap.h new file mode 100644 index 000000000000..62e3d19c9ad7 --- /dev/null +++ b/arch/arm/include/asm/idmap.h @@ -0,0 +1,17 @@ +#ifndef __ASM_IDMAP_H +#define __ASM_IDMAP_H + +#include <linux/compiler.h> +#include <asm/pgtable.h> + +/* Tag a function as requiring to be executed via an identity mapping. */ +#define __idmap __section(.idmap.text) noinline notrace + +extern pgd_t *idmap_pgd; + +void identity_mapping_add(pgd_t *, unsigned long, unsigned long); +void identity_mapping_del(pgd_t *, unsigned long, unsigned long); + +void setup_mm_for_reboot(void); + +#endif /* __ASM_IDMAP_H */ diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index 9451dce3a553..03893a55e680 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -346,9 +346,6 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) #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 ef5640b9e218..8afadda37459 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -31,6 +31,7 @@ #include <asm/cpu.h> #include <asm/cputype.h> #include <asm/exception.h> +#include <asm/idmap.h> #include <asm/topology.h> #include <asm/mmu_context.h> #include <asm/pgtable.h> diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index 20b3041e0860..f76e75548670 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -13,6 +13,12 @@ *(.proc.info.init) \ VMLINUX_SYMBOL(__proc_info_end) = .; +#define IDMAP_TEXT \ + ALIGN_FUNCTION(); \ + VMLINUX_SYMBOL(__idmap_text_start) = .; \ + *(.idmap.text) \ + VMLINUX_SYMBOL(__idmap_text_end) = .; + #ifdef CONFIG_HOTPLUG_CPU #define ARM_CPU_DISCARD(x) #define ARM_CPU_KEEP(x) x @@ -92,6 +98,7 @@ SECTIONS SCHED_TEXT LOCK_TEXT KPROBES_TEXT + IDMAP_TEXT #ifdef CONFIG_MMU *(.fixup) #endif diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c index 296ad2eaddb0..cda5ea3157a7 100644 --- a/arch/arm/mm/idmap.c +++ b/arch/arm/mm/idmap.c @@ -1,8 +1,12 @@ #include <linux/kernel.h> #include <asm/cputype.h> +#include <asm/idmap.h> #include <asm/pgalloc.h> #include <asm/pgtable.h> +#include <asm/sections.h> + +pgd_t *idmap_pgd; static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end, unsigned long prot) @@ -73,6 +77,28 @@ void identity_mapping_del(pgd_t *pgd, unsigned long addr, unsigned long end) } #endif +extern char __idmap_text_start[], __idmap_text_end[]; + +static int __init init_static_idmap(void) +{ + phys_addr_t idmap_start, idmap_end; + + idmap_pgd = pgd_alloc(&init_mm); + if (!idmap_pgd) + return -ENOMEM; + + /* Add an identity mapping for the physical address of the section. */ + idmap_start = virt_to_phys((void *)__idmap_text_start); + idmap_end = virt_to_phys((void *)__idmap_text_end); + + pr_info("Setting up static identity map for 0x%llx - 0x%llx\n", + (long long)idmap_start, (long long)idmap_end); + identity_mapping_add(idmap_pgd, idmap_start, idmap_end); + + return 0; +} +arch_initcall(init_static_idmap); + /* * 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 |