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/pgtable.h> 33 #include <asm/sections.h> 34 #include <asm/tlb.h> 35 #include <asm/mmu_context.h> 36 #include <asm/cpuinfo.h> 37 #include <asm/processor.h> 38 39 pgd_t *pgd_current; 40 41 /* 42 * paging_init() continues the virtual memory environment setup which 43 * was begun by the code in arch/head.S. 44 * The parameters are pointers to where to stick the starting and ending 45 * addresses of available kernel virtual memory. 46 */ 47 void __init paging_init(void) 48 { 49 unsigned long zones_size[MAX_NR_ZONES]; 50 51 memset(zones_size, 0, sizeof(zones_size)); 52 53 pagetable_init(); 54 pgd_current = swapper_pg_dir; 55 56 zones_size[ZONE_NORMAL] = max_mapnr; 57 58 /* pass the memory from the bootmem allocator to the main allocator */ 59 free_area_init(zones_size); 60 61 flush_dcache_range((unsigned long)empty_zero_page, 62 (unsigned long)empty_zero_page + PAGE_SIZE); 63 } 64 65 void __init mem_init(void) 66 { 67 unsigned long end_mem = memory_end; /* this must not include 68 kernel stack at top */ 69 70 pr_debug("mem_init: start=%lx, end=%lx\n", memory_start, memory_end); 71 72 end_mem &= PAGE_MASK; 73 high_memory = __va(end_mem); 74 75 /* this will put all memory onto the freelists */ 76 memblock_free_all(); 77 mem_init_print_info(NULL); 78 } 79 80 void __init mmu_init(void) 81 { 82 flush_tlb_all(); 83 } 84 85 #ifdef CONFIG_BLK_DEV_INITRD 86 void __init free_initrd_mem(unsigned long start, unsigned long end) 87 { 88 free_reserved_area((void *)start, (void *)end, -1, "initrd"); 89 } 90 #endif 91 92 void __ref free_initmem(void) 93 { 94 free_initmem_default(-1); 95 } 96 97 #define __page_aligned(order) __aligned(PAGE_SIZE << (order)) 98 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER); 99 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER); 100 static struct page *kuser_page[1]; 101 102 static int alloc_kuser_page(void) 103 { 104 extern char __kuser_helper_start[], __kuser_helper_end[]; 105 int kuser_sz = __kuser_helper_end - __kuser_helper_start; 106 unsigned long vpage; 107 108 vpage = get_zeroed_page(GFP_ATOMIC); 109 if (!vpage) 110 return -ENOMEM; 111 112 /* Copy kuser helpers */ 113 memcpy((void *)vpage, __kuser_helper_start, kuser_sz); 114 115 flush_icache_range(vpage, vpage + KUSER_SIZE); 116 kuser_page[0] = virt_to_page(vpage); 117 118 return 0; 119 } 120 arch_initcall(alloc_kuser_page); 121 122 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) 123 { 124 struct mm_struct *mm = current->mm; 125 int ret; 126 127 down_write(&mm->mmap_sem); 128 129 /* Map kuser helpers to user space address */ 130 ret = install_special_mapping(mm, KUSER_BASE, KUSER_SIZE, 131 VM_READ | VM_EXEC | VM_MAYREAD | 132 VM_MAYEXEC, kuser_page); 133 134 up_write(&mm->mmap_sem); 135 136 return ret; 137 } 138 139 const char *arch_vma_name(struct vm_area_struct *vma) 140 { 141 return (vma->vm_start == KUSER_BASE) ? "[kuser]" : NULL; 142 } 143