1 /* 2 * Copyright (C) 2013 Altera Corporation 3 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> 4 * Copyright (C) 2009 Wind River Systems Inc 5 * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com 6 * Copyright (C) 2004 Microtronix Datacom Ltd 7 * 8 * based on arch/m68k/mm/init.c 9 * 10 * This file is subject to the terms and conditions of the GNU General Public 11 * License. See the file "COPYING" in the main directory of this archive 12 * for more details. 13 */ 14 15 #include <linux/signal.h> 16 #include <linux/sched.h> 17 #include <linux/kernel.h> 18 #include <linux/errno.h> 19 #include <linux/string.h> 20 #include <linux/types.h> 21 #include <linux/ptrace.h> 22 #include <linux/mman.h> 23 #include <linux/mm.h> 24 #include <linux/init.h> 25 #include <linux/pagemap.h> 26 #include <linux/memblock.h> 27 #include <linux/slab.h> 28 #include <linux/binfmts.h> 29 30 #include <asm/setup.h> 31 #include <asm/page.h> 32 #include <asm/sections.h> 33 #include <asm/tlb.h> 34 #include <asm/mmu_context.h> 35 #include <asm/cpuinfo.h> 36 #include <asm/processor.h> 37 38 pgd_t *pgd_current; 39 40 /* 41 * paging_init() continues the virtual memory environment setup which 42 * was begun by the code in arch/head.S. 43 * The parameters are pointers to where to stick the starting and ending 44 * addresses of available kernel virtual memory. 45 */ 46 void __init paging_init(void) 47 { 48 unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 }; 49 50 pagetable_init(); 51 pgd_current = swapper_pg_dir; 52 53 max_zone_pfn[ZONE_NORMAL] = max_mapnr; 54 55 /* pass the memory from the bootmem allocator to the main allocator */ 56 free_area_init(max_zone_pfn); 57 58 flush_dcache_range((unsigned long)empty_zero_page, 59 (unsigned long)empty_zero_page + PAGE_SIZE); 60 } 61 62 void __init mem_init(void) 63 { 64 unsigned long end_mem = memory_end; /* this must not include 65 kernel stack at top */ 66 67 pr_debug("mem_init: start=%lx, end=%lx\n", memory_start, memory_end); 68 69 end_mem &= PAGE_MASK; 70 high_memory = __va(end_mem); 71 72 /* this will put all memory onto the freelists */ 73 memblock_free_all(); 74 mem_init_print_info(NULL); 75 } 76 77 void __init mmu_init(void) 78 { 79 flush_tlb_all(); 80 } 81 82 #define __page_aligned(order) __aligned(PAGE_SIZE << (order)) 83 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER); 84 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER); 85 static struct page *kuser_page[1]; 86 87 static int alloc_kuser_page(void) 88 { 89 extern char __kuser_helper_start[], __kuser_helper_end[]; 90 int kuser_sz = __kuser_helper_end - __kuser_helper_start; 91 unsigned long vpage; 92 93 vpage = get_zeroed_page(GFP_ATOMIC); 94 if (!vpage) 95 return -ENOMEM; 96 97 /* Copy kuser helpers */ 98 memcpy((void *)vpage, __kuser_helper_start, kuser_sz); 99 100 flush_icache_range(vpage, vpage + KUSER_SIZE); 101 kuser_page[0] = virt_to_page(vpage); 102 103 return 0; 104 } 105 arch_initcall(alloc_kuser_page); 106 107 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) 108 { 109 struct mm_struct *mm = current->mm; 110 int ret; 111 112 mmap_write_lock(mm); 113 114 /* Map kuser helpers to user space address */ 115 ret = install_special_mapping(mm, KUSER_BASE, KUSER_SIZE, 116 VM_READ | VM_EXEC | VM_MAYREAD | 117 VM_MAYEXEC, kuser_page); 118 119 mmap_write_unlock(mm); 120 121 return ret; 122 } 123 124 const char *arch_vma_name(struct vm_area_struct *vma) 125 { 126 return (vma->vm_start == KUSER_BASE) ? "[kuser]" : NULL; 127 } 128