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
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