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 #include <linux/execmem.h> 30 31 #include <asm/setup.h> 32 #include <asm/page.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 max_zone_pfn[MAX_NR_ZONES] = { 0 }; 50 51 pagetable_init(); 52 pgd_current = swapper_pg_dir; 53 54 max_zone_pfn[ZONE_NORMAL] = max_mapnr; 55 56 /* pass the memory from the bootmem allocator to the main allocator */ 57 free_area_init(max_zone_pfn); 58 59 flush_dcache_range((unsigned long)empty_zero_page, 60 (unsigned long)empty_zero_page + PAGE_SIZE); 61 } 62 63 void __init mem_init(void) 64 { 65 unsigned long end_mem = memory_end; /* this must not include 66 kernel stack at top */ 67 68 pr_debug("mem_init: start=%lx, end=%lx\n", memory_start, memory_end); 69 70 end_mem &= PAGE_MASK; 71 high_memory = __va(end_mem); 72 73 /* this will put all memory onto the freelists */ 74 memblock_free_all(); 75 } 76 77 void __init mmu_init(void) 78 { 79 flush_tlb_all(); 80 } 81 82 pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE); 83 pte_t invalid_pte_table[PTRS_PER_PTE] __aligned(PAGE_SIZE); 84 static struct page *kuser_page[1]; 85 86 static int alloc_kuser_page(void) 87 { 88 extern char __kuser_helper_start[], __kuser_helper_end[]; 89 int kuser_sz = __kuser_helper_end - __kuser_helper_start; 90 unsigned long vpage; 91 92 vpage = get_zeroed_page(GFP_ATOMIC); 93 if (!vpage) 94 return -ENOMEM; 95 96 /* Copy kuser helpers */ 97 memcpy((void *)vpage, __kuser_helper_start, kuser_sz); 98 99 flush_icache_range(vpage, vpage + KUSER_SIZE); 100 kuser_page[0] = virt_to_page(vpage); 101 102 return 0; 103 } 104 arch_initcall(alloc_kuser_page); 105 106 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) 107 { 108 struct mm_struct *mm = current->mm; 109 int ret; 110 111 mmap_write_lock(mm); 112 113 /* Map kuser helpers to user space address */ 114 ret = install_special_mapping(mm, KUSER_BASE, KUSER_SIZE, 115 VM_READ | VM_EXEC | VM_MAYREAD | 116 VM_MAYEXEC, kuser_page); 117 118 mmap_write_unlock(mm); 119 120 return ret; 121 } 122 123 const char *arch_vma_name(struct vm_area_struct *vma) 124 { 125 return (vma->vm_start == KUSER_BASE) ? "[kuser]" : NULL; 126 } 127 128 static const pgprot_t protection_map[16] = { 129 [VM_NONE] = MKP(0, 0, 0), 130 [VM_READ] = MKP(0, 0, 1), 131 [VM_WRITE] = MKP(0, 0, 0), 132 [VM_WRITE | VM_READ] = MKP(0, 0, 1), 133 [VM_EXEC] = MKP(1, 0, 0), 134 [VM_EXEC | VM_READ] = MKP(1, 0, 1), 135 [VM_EXEC | VM_WRITE] = MKP(1, 0, 0), 136 [VM_EXEC | VM_WRITE | VM_READ] = MKP(1, 0, 1), 137 [VM_SHARED] = MKP(0, 0, 0), 138 [VM_SHARED | VM_READ] = MKP(0, 0, 1), 139 [VM_SHARED | VM_WRITE] = MKP(0, 1, 0), 140 [VM_SHARED | VM_WRITE | VM_READ] = MKP(0, 1, 1), 141 [VM_SHARED | VM_EXEC] = MKP(1, 0, 0), 142 [VM_SHARED | VM_EXEC | VM_READ] = MKP(1, 0, 1), 143 [VM_SHARED | VM_EXEC | VM_WRITE] = MKP(1, 1, 0), 144 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = MKP(1, 1, 1) 145 }; 146 DECLARE_VM_GET_PAGE_PROT 147 148 #ifdef CONFIG_EXECMEM 149 static struct execmem_info execmem_info __ro_after_init; 150 151 struct execmem_info __init *execmem_arch_setup(void) 152 { 153 execmem_info = (struct execmem_info){ 154 .ranges = { 155 [EXECMEM_DEFAULT] = { 156 .start = MODULES_VADDR, 157 .end = MODULES_END, 158 .pgprot = PAGE_KERNEL_EXEC, 159 .alignment = 1, 160 }, 161 }, 162 }; 163 164 return &execmem_info; 165 } 166 #endif /* CONFIG_EXECMEM */ 167