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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
39pgd_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 */
47void __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
63void __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
77void __init mmu_init(void)
78{
79 flush_tlb_all();
80}
81
82pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE);
83pte_t invalid_pte_table[PTRS_PER_PTE] __aligned(PAGE_SIZE);
84static struct page *kuser_page[1];
85
86static 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}
104arch_initcall(alloc_kuser_page);
105
106int 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
123const char *arch_vma_name(struct vm_area_struct *vma)
124{
125 return (vma->vm_start == KUSER_BASE) ? "[kuser]" : NULL;
126}
127
128static 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};
146DECLARE_VM_GET_PAGE_PROT
147
148#ifdef CONFIG_EXECMEM
149static struct execmem_info execmem_info __ro_after_init;
150
151struct 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 */