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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 */
5
6#include <linux/stddef.h>
7#include <linux/module.h>
8#include <linux/memblock.h>
9#include <linux/highmem.h>
10#include <linux/mm.h>
11#include <linux/swap.h>
12#include <linux/slab.h>
13#include <asm/fixmap.h>
14#include <asm/page.h>
15#include <as-layout.h>
16#include <init.h>
17#include <kern.h>
18#include <kern_util.h>
19#include <mem_user.h>
20#include <os.h>
21
22/* allocated in paging_init, zeroed in mem_init, and unchanged thereafter */
23unsigned long *empty_zero_page = NULL;
24EXPORT_SYMBOL(empty_zero_page);
25
26/*
27 * Initialized during boot, and readonly for initializing page tables
28 * afterwards
29 */
30pgd_t swapper_pg_dir[PTRS_PER_PGD];
31
32/* Initialized at boot time, and readonly after that */
33unsigned long long highmem;
34EXPORT_SYMBOL(highmem);
35int kmalloc_ok = 0;
36
37/* Used during early boot */
38static unsigned long brk_end;
39
40void __init mem_init(void)
41{
42 /* clear the zero-page */
43 memset(empty_zero_page, 0, PAGE_SIZE);
44
45 /* Map in the area just after the brk now that kmalloc is about
46 * to be turned on.
47 */
48 brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
49 map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
50 memblock_free(__pa(brk_end), uml_reserved - brk_end);
51 uml_reserved = brk_end;
52
53 /* this will put all low memory onto the freelists */
54 memblock_free_all();
55 max_low_pfn = totalram_pages();
56 max_pfn = max_low_pfn;
57 mem_init_print_info(NULL);
58 kmalloc_ok = 1;
59}
60
61/*
62 * Create a page table and place a pointer to it in a middle page
63 * directory entry.
64 */
65static void __init one_page_table_init(pmd_t *pmd)
66{
67 if (pmd_none(*pmd)) {
68 pte_t *pte = (pte_t *) memblock_alloc_low(PAGE_SIZE,
69 PAGE_SIZE);
70 if (!pte)
71 panic("%s: Failed to allocate %lu bytes align=%lx\n",
72 __func__, PAGE_SIZE, PAGE_SIZE);
73
74 set_pmd(pmd, __pmd(_KERNPG_TABLE +
75 (unsigned long) __pa(pte)));
76 if (pte != pte_offset_kernel(pmd, 0))
77 BUG();
78 }
79}
80
81static void __init one_md_table_init(pud_t *pud)
82{
83#ifdef CONFIG_3_LEVEL_PGTABLES
84 pmd_t *pmd_table = (pmd_t *) memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
85 if (!pmd_table)
86 panic("%s: Failed to allocate %lu bytes align=%lx\n",
87 __func__, PAGE_SIZE, PAGE_SIZE);
88
89 set_pud(pud, __pud(_KERNPG_TABLE + (unsigned long) __pa(pmd_table)));
90 if (pmd_table != pmd_offset(pud, 0))
91 BUG();
92#endif
93}
94
95static void __init fixrange_init(unsigned long start, unsigned long end,
96 pgd_t *pgd_base)
97{
98 pgd_t *pgd;
99 p4d_t *p4d;
100 pud_t *pud;
101 pmd_t *pmd;
102 int i, j;
103 unsigned long vaddr;
104
105 vaddr = start;
106 i = pgd_index(vaddr);
107 j = pmd_index(vaddr);
108 pgd = pgd_base + i;
109
110 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
111 p4d = p4d_offset(pgd, vaddr);
112 pud = pud_offset(p4d, vaddr);
113 if (pud_none(*pud))
114 one_md_table_init(pud);
115 pmd = pmd_offset(pud, vaddr);
116 for (; (j < PTRS_PER_PMD) && (vaddr < end); pmd++, j++) {
117 one_page_table_init(pmd);
118 vaddr += PMD_SIZE;
119 }
120 j = 0;
121 }
122}
123
124static void __init fixaddr_user_init( void)
125{
126#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
127 long size = FIXADDR_USER_END - FIXADDR_USER_START;
128 pte_t *pte;
129 phys_t p;
130 unsigned long v, vaddr = FIXADDR_USER_START;
131
132 if (!size)
133 return;
134
135 fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir);
136 v = (unsigned long) memblock_alloc_low(size, PAGE_SIZE);
137 if (!v)
138 panic("%s: Failed to allocate %lu bytes align=%lx\n",
139 __func__, size, PAGE_SIZE);
140
141 memcpy((void *) v , (void *) FIXADDR_USER_START, size);
142 p = __pa(v);
143 for ( ; size > 0; size -= PAGE_SIZE, vaddr += PAGE_SIZE,
144 p += PAGE_SIZE) {
145 pte = virt_to_kpte(vaddr);
146 pte_set_val(*pte, p, PAGE_READONLY);
147 }
148#endif
149}
150
151void __init paging_init(void)
152{
153 unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
154 unsigned long vaddr;
155
156 empty_zero_page = (unsigned long *) memblock_alloc_low(PAGE_SIZE,
157 PAGE_SIZE);
158 if (!empty_zero_page)
159 panic("%s: Failed to allocate %lu bytes align=%lx\n",
160 __func__, PAGE_SIZE, PAGE_SIZE);
161
162 max_zone_pfn[ZONE_NORMAL] = end_iomem >> PAGE_SHIFT;
163 free_area_init(max_zone_pfn);
164
165 /*
166 * Fixed mappings, only the page table structure has to be
167 * created - mappings will be set by set_fixmap():
168 */
169 vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
170 fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
171
172 fixaddr_user_init();
173}
174
175/*
176 * This can't do anything because nothing in the kernel image can be freed
177 * since it's not in kernel physical memory.
178 */
179
180void free_initmem(void)
181{
182}
183
184/* Allocate and free page tables. */
185
186pgd_t *pgd_alloc(struct mm_struct *mm)
187{
188 pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
189
190 if (pgd) {
191 memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
192 memcpy(pgd + USER_PTRS_PER_PGD,
193 swapper_pg_dir + USER_PTRS_PER_PGD,
194 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
195 }
196 return pgd;
197}
198
199void *uml_kmalloc(int size, int flags)
200{
201 return kmalloc(size, flags);
202}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 */
5
6#include <linux/stddef.h>
7#include <linux/module.h>
8#include <linux/memblock.h>
9#include <linux/highmem.h>
10#include <linux/mm.h>
11#include <linux/swap.h>
12#include <linux/slab.h>
13#include <asm/fixmap.h>
14#include <asm/page.h>
15#include <as-layout.h>
16#include <init.h>
17#include <kern.h>
18#include <kern_util.h>
19#include <mem_user.h>
20#include <os.h>
21
22/* allocated in paging_init, zeroed in mem_init, and unchanged thereafter */
23unsigned long *empty_zero_page = NULL;
24EXPORT_SYMBOL(empty_zero_page);
25
26/*
27 * Initialized during boot, and readonly for initializing page tables
28 * afterwards
29 */
30pgd_t swapper_pg_dir[PTRS_PER_PGD];
31
32/* Initialized at boot time, and readonly after that */
33unsigned long long highmem;
34EXPORT_SYMBOL(highmem);
35int kmalloc_ok = 0;
36
37/* Used during early boot */
38static unsigned long brk_end;
39
40void __init mem_init(void)
41{
42 /* clear the zero-page */
43 memset(empty_zero_page, 0, PAGE_SIZE);
44
45 /* Map in the area just after the brk now that kmalloc is about
46 * to be turned on.
47 */
48 brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
49 map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
50 memblock_free(__pa(brk_end), uml_reserved - brk_end);
51 uml_reserved = brk_end;
52
53 /* this will put all low memory onto the freelists */
54 memblock_free_all();
55 max_low_pfn = totalram_pages();
56 max_pfn = max_low_pfn;
57 kmalloc_ok = 1;
58}
59
60/*
61 * Create a page table and place a pointer to it in a middle page
62 * directory entry.
63 */
64static void __init one_page_table_init(pmd_t *pmd)
65{
66 if (pmd_none(*pmd)) {
67 pte_t *pte = (pte_t *) memblock_alloc_low(PAGE_SIZE,
68 PAGE_SIZE);
69 if (!pte)
70 panic("%s: Failed to allocate %lu bytes align=%lx\n",
71 __func__, PAGE_SIZE, PAGE_SIZE);
72
73 set_pmd(pmd, __pmd(_KERNPG_TABLE +
74 (unsigned long) __pa(pte)));
75 BUG_ON(pte != pte_offset_kernel(pmd, 0));
76 }
77}
78
79static void __init one_md_table_init(pud_t *pud)
80{
81#ifdef CONFIG_3_LEVEL_PGTABLES
82 pmd_t *pmd_table = (pmd_t *) memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
83 if (!pmd_table)
84 panic("%s: Failed to allocate %lu bytes align=%lx\n",
85 __func__, PAGE_SIZE, PAGE_SIZE);
86
87 set_pud(pud, __pud(_KERNPG_TABLE + (unsigned long) __pa(pmd_table)));
88 if (pmd_table != pmd_offset(pud, 0))
89 BUG();
90#endif
91}
92
93static void __init fixrange_init(unsigned long start, unsigned long end,
94 pgd_t *pgd_base)
95{
96 pgd_t *pgd;
97 p4d_t *p4d;
98 pud_t *pud;
99 pmd_t *pmd;
100 int i, j;
101 unsigned long vaddr;
102
103 vaddr = start;
104 i = pgd_index(vaddr);
105 j = pmd_index(vaddr);
106 pgd = pgd_base + i;
107
108 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
109 p4d = p4d_offset(pgd, vaddr);
110 pud = pud_offset(p4d, vaddr);
111 if (pud_none(*pud))
112 one_md_table_init(pud);
113 pmd = pmd_offset(pud, vaddr);
114 for (; (j < PTRS_PER_PMD) && (vaddr < end); pmd++, j++) {
115 one_page_table_init(pmd);
116 vaddr += PMD_SIZE;
117 }
118 j = 0;
119 }
120}
121
122static void __init fixaddr_user_init( void)
123{
124#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
125 long size = FIXADDR_USER_END - FIXADDR_USER_START;
126 pte_t *pte;
127 phys_t p;
128 unsigned long v, vaddr = FIXADDR_USER_START;
129
130 if (!size)
131 return;
132
133 fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir);
134 v = (unsigned long) memblock_alloc_low(size, PAGE_SIZE);
135 if (!v)
136 panic("%s: Failed to allocate %lu bytes align=%lx\n",
137 __func__, size, PAGE_SIZE);
138
139 memcpy((void *) v , (void *) FIXADDR_USER_START, size);
140 p = __pa(v);
141 for ( ; size > 0; size -= PAGE_SIZE, vaddr += PAGE_SIZE,
142 p += PAGE_SIZE) {
143 pte = virt_to_kpte(vaddr);
144 pte_set_val(*pte, p, PAGE_READONLY);
145 }
146#endif
147}
148
149void __init paging_init(void)
150{
151 unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
152 unsigned long vaddr;
153
154 empty_zero_page = (unsigned long *) memblock_alloc_low(PAGE_SIZE,
155 PAGE_SIZE);
156 if (!empty_zero_page)
157 panic("%s: Failed to allocate %lu bytes align=%lx\n",
158 __func__, PAGE_SIZE, PAGE_SIZE);
159
160 max_zone_pfn[ZONE_NORMAL] = end_iomem >> PAGE_SHIFT;
161 free_area_init(max_zone_pfn);
162
163 /*
164 * Fixed mappings, only the page table structure has to be
165 * created - mappings will be set by set_fixmap():
166 */
167 vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
168 fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
169
170 fixaddr_user_init();
171}
172
173/*
174 * This can't do anything because nothing in the kernel image can be freed
175 * since it's not in kernel physical memory.
176 */
177
178void free_initmem(void)
179{
180}
181
182/* Allocate and free page tables. */
183
184pgd_t *pgd_alloc(struct mm_struct *mm)
185{
186 pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
187
188 if (pgd) {
189 memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
190 memcpy(pgd + USER_PTRS_PER_PGD,
191 swapper_pg_dir + USER_PTRS_PER_PGD,
192 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
193 }
194 return pgd;
195}
196
197void *uml_kmalloc(int size, int flags)
198{
199 return kmalloc(size, flags);
200}