diff --git a/arch/mn10300/include/asm/pgtable.h b/arch/mn10300/include/asm/pgtable.h index cd568bf5407e..a1e894b5f65b 100644 --- a/arch/mn10300/include/asm/pgtable.h +++ b/arch/mn10300/include/asm/pgtable.h @@ -182,6 +182,9 @@ extern pte_t kernel_vmalloc_ptes[(VMALLOC_END - VMALLOC_START) / PAGE_SIZE]; #define PAGE_KERNEL_LARGE __pgprot(__PAGE_KERNEL_LARGE) #define PAGE_KERNEL_LARGE_EXEC __pgprot(__PAGE_KERNEL_LARGE_EXEC) +#define __PAGE_USERIO (__PAGE_KERNEL_BASE | _PAGE_PROT_WKWU | _PAGE_NX) +#define PAGE_USERIO __pgprot(__PAGE_USERIO) + /* * Whilst the MN10300 can do page protection for execute (given separate data * and insn TLBs), we are not supporting it at the moment. Write permission, diff --git a/arch/mn10300/mm/init.c b/arch/mn10300/mm/init.c index 1daf97fd7c99..48907cc3bdb7 100644 --- a/arch/mn10300/mm/init.c +++ b/arch/mn10300/mm/init.c @@ -41,6 +41,10 @@ DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); unsigned long highstart_pfn, highend_pfn; +#ifdef CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT +static struct vm_struct user_iomap_vm; +#endif + /* * set up paging */ @@ -73,6 +77,23 @@ void __init paging_init(void) /* pass the memory from the bootmem allocator to the main allocator */ free_area_init(zones_size); +#ifdef CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT + /* The Atomic Operation Unit registers need to be mapped to userspace + * for all processes. The following uses vm_area_register_early() to + * reserve the first page of the vmalloc area and sets the pte for that + * page. + * + * glibc hardcodes this virtual mapping, so we're pretty much stuck with + * it from now on. + */ + user_iomap_vm.flags = VM_USERMAP; + user_iomap_vm.size = 1 << PAGE_SHIFT; + vm_area_register_early(&user_iomap_vm, PAGE_SIZE); + ppte = kernel_vmalloc_ptes; + set_pte(ppte, pfn_pte(USER_ATOMIC_OPS_PAGE_ADDR >> PAGE_SHIFT, + PAGE_USERIO)); +#endif + local_flush_tlb_all(); }