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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/*
2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
4 */
5
6#include <linux/stddef.h>
7#include <linux/module.h>
8#include <linux/bootmem.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;
34int kmalloc_ok = 0;
35
36/* Used during early boot */
37static unsigned long brk_end;
38
39void __init mem_init(void)
40{
41 /* clear the zero-page */
42 memset(empty_zero_page, 0, PAGE_SIZE);
43
44 /* Map in the area just after the brk now that kmalloc is about
45 * to be turned on.
46 */
47 brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
48 map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
49 free_bootmem(__pa(brk_end), uml_reserved - brk_end);
50 uml_reserved = brk_end;
51
52 /* this will put all low memory onto the freelists */
53 free_all_bootmem();
54 max_low_pfn = totalram_pages;
55 max_pfn = totalram_pages;
56 mem_init_print_info(NULL);
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 *) alloc_bootmem_low_pages(PAGE_SIZE);
68 set_pmd(pmd, __pmd(_KERNPG_TABLE +
69 (unsigned long) __pa(pte)));
70 if (pte != pte_offset_kernel(pmd, 0))
71 BUG();
72 }
73}
74
75static void __init one_md_table_init(pud_t *pud)
76{
77#ifdef CONFIG_3_LEVEL_PGTABLES
78 pmd_t *pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE);
79 set_pud(pud, __pud(_KERNPG_TABLE + (unsigned long) __pa(pmd_table)));
80 if (pmd_table != pmd_offset(pud, 0))
81 BUG();
82#endif
83}
84
85static void __init fixrange_init(unsigned long start, unsigned long end,
86 pgd_t *pgd_base)
87{
88 pgd_t *pgd;
89 pud_t *pud;
90 pmd_t *pmd;
91 int i, j;
92 unsigned long vaddr;
93
94 vaddr = start;
95 i = pgd_index(vaddr);
96 j = pmd_index(vaddr);
97 pgd = pgd_base + i;
98
99 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
100 pud = pud_offset(pgd, vaddr);
101 if (pud_none(*pud))
102 one_md_table_init(pud);
103 pmd = pmd_offset(pud, vaddr);
104 for (; (j < PTRS_PER_PMD) && (vaddr < end); pmd++, j++) {
105 one_page_table_init(pmd);
106 vaddr += PMD_SIZE;
107 }
108 j = 0;
109 }
110}
111
112static void __init fixaddr_user_init( void)
113{
114#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
115 long size = FIXADDR_USER_END - FIXADDR_USER_START;
116 pgd_t *pgd;
117 pud_t *pud;
118 pmd_t *pmd;
119 pte_t *pte;
120 phys_t p;
121 unsigned long v, vaddr = FIXADDR_USER_START;
122
123 if (!size)
124 return;
125
126 fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir);
127 v = (unsigned long) alloc_bootmem_low_pages(size);
128 memcpy((void *) v , (void *) FIXADDR_USER_START, size);
129 p = __pa(v);
130 for ( ; size > 0; size -= PAGE_SIZE, vaddr += PAGE_SIZE,
131 p += PAGE_SIZE) {
132 pgd = swapper_pg_dir + pgd_index(vaddr);
133 pud = pud_offset(pgd, vaddr);
134 pmd = pmd_offset(pud, vaddr);
135 pte = pte_offset_kernel(pmd, vaddr);
136 pte_set_val(*pte, p, PAGE_READONLY);
137 }
138#endif
139}
140
141void __init paging_init(void)
142{
143 unsigned long zones_size[MAX_NR_ZONES], vaddr;
144 int i;
145
146 empty_zero_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
147 for (i = 0; i < ARRAY_SIZE(zones_size); i++)
148 zones_size[i] = 0;
149
150 zones_size[ZONE_NORMAL] = (end_iomem >> PAGE_SHIFT) -
151 (uml_physmem >> PAGE_SHIFT);
152 free_area_init(zones_size);
153
154 /*
155 * Fixed mappings, only the page table structure has to be
156 * created - mappings will be set by set_fixmap():
157 */
158 vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
159 fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
160
161 fixaddr_user_init();
162}
163
164/*
165 * This can't do anything because nothing in the kernel image can be freed
166 * since it's not in kernel physical memory.
167 */
168
169void free_initmem(void)
170{
171}
172
173#ifdef CONFIG_BLK_DEV_INITRD
174void free_initrd_mem(unsigned long start, unsigned long end)
175{
176 free_reserved_area((void *)start, (void *)end, -1, "initrd");
177}
178#endif
179
180/* Allocate and free page tables. */
181
182pgd_t *pgd_alloc(struct mm_struct *mm)
183{
184 pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
185
186 if (pgd) {
187 memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
188 memcpy(pgd + USER_PTRS_PER_PGD,
189 swapper_pg_dir + USER_PTRS_PER_PGD,
190 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
191 }
192 return pgd;
193}
194
195void pgd_free(struct mm_struct *mm, pgd_t *pgd)
196{
197 free_page((unsigned long) pgd);
198}
199
200pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
201{
202 pte_t *pte;
203
204 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
205 return pte;
206}
207
208pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
209{
210 struct page *pte;
211
212 pte = alloc_page(GFP_KERNEL|__GFP_ZERO);
213 if (!pte)
214 return NULL;
215 if (!pgtable_page_ctor(pte)) {
216 __free_page(pte);
217 return NULL;
218 }
219 return pte;
220}
221
222#ifdef CONFIG_3_LEVEL_PGTABLES
223pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
224{
225 pmd_t *pmd = (pmd_t *) __get_free_page(GFP_KERNEL);
226
227 if (pmd)
228 memset(pmd, 0, PAGE_SIZE);
229
230 return pmd;
231}
232#endif
233
234void *uml_kmalloc(int size, int flags)
235{
236 return kmalloc(size, flags);
237}