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/bootmem.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
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 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
65void __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	free_all_bootmem();
77	mem_init_print_info(NULL);
78}
79
80void __init mmu_init(void)
81{
82	flush_tlb_all();
83}
84
85#ifdef CONFIG_BLK_DEV_INITRD
86void __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
92void __init_refok free_initmem(void)
93{
94	free_initmem_default(-1);
95}
96
97#define __page_aligned(order) __aligned(PAGE_SIZE << (order))
98pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER);
99pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER);
100static struct page *kuser_page[1];
101
102static 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}
120arch_initcall(alloc_kuser_page);
121
122int 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
139const char *arch_vma_name(struct vm_area_struct *vma)
140{
141	return (vma->vm_start == KUSER_BASE) ? "[kuser]" : NULL;
142}
143