blk: rq_data_dir() should not return a boolean
[cris-mirror.git] / arch / um / kernel / mem.c
blobb2a2dff50b4e1983a89b9257de79417333c1f2b6
1 /*
2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
4 */
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>
22 /* allocated in paging_init, zeroed in mem_init, and unchanged thereafter */
23 unsigned long *empty_zero_page = NULL;
24 EXPORT_SYMBOL(empty_zero_page);
25 /* allocated in paging_init and unchanged thereafter */
26 static unsigned long *empty_bad_page = NULL;
29 * Initialized during boot, and readonly for initializing page tables
30 * afterwards
32 pgd_t swapper_pg_dir[PTRS_PER_PGD];
34 /* Initialized at boot time, and readonly after that */
35 unsigned long long highmem;
36 int kmalloc_ok = 0;
38 /* Used during early boot */
39 static unsigned long brk_end;
41 void __init mem_init(void)
43 /* clear the zero-page */
44 memset(empty_zero_page, 0, PAGE_SIZE);
46 /* Map in the area just after the brk now that kmalloc is about
47 * to be turned on.
49 brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
50 map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
51 free_bootmem(__pa(brk_end), uml_reserved - brk_end);
52 uml_reserved = brk_end;
54 /* this will put all low memory onto the freelists */
55 free_all_bootmem();
56 max_low_pfn = totalram_pages;
57 max_pfn = totalram_pages;
58 mem_init_print_info(NULL);
59 kmalloc_ok = 1;
63 * Create a page table and place a pointer to it in a middle page
64 * directory entry.
66 static void __init one_page_table_init(pmd_t *pmd)
68 if (pmd_none(*pmd)) {
69 pte_t *pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
70 set_pmd(pmd, __pmd(_KERNPG_TABLE +
71 (unsigned long) __pa(pte)));
72 if (pte != pte_offset_kernel(pmd, 0))
73 BUG();
77 static void __init one_md_table_init(pud_t *pud)
79 #ifdef CONFIG_3_LEVEL_PGTABLES
80 pmd_t *pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE);
81 set_pud(pud, __pud(_KERNPG_TABLE + (unsigned long) __pa(pmd_table)));
82 if (pmd_table != pmd_offset(pud, 0))
83 BUG();
84 #endif
87 static void __init fixrange_init(unsigned long start, unsigned long end,
88 pgd_t *pgd_base)
90 pgd_t *pgd;
91 pud_t *pud;
92 pmd_t *pmd;
93 int i, j;
94 unsigned long vaddr;
96 vaddr = start;
97 i = pgd_index(vaddr);
98 j = pmd_index(vaddr);
99 pgd = pgd_base + i;
101 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
102 pud = pud_offset(pgd, vaddr);
103 if (pud_none(*pud))
104 one_md_table_init(pud);
105 pmd = pmd_offset(pud, vaddr);
106 for (; (j < PTRS_PER_PMD) && (vaddr < end); pmd++, j++) {
107 one_page_table_init(pmd);
108 vaddr += PMD_SIZE;
110 j = 0;
114 static void __init fixaddr_user_init( void)
116 #ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
117 long size = FIXADDR_USER_END - FIXADDR_USER_START;
118 pgd_t *pgd;
119 pud_t *pud;
120 pmd_t *pmd;
121 pte_t *pte;
122 phys_t p;
123 unsigned long v, vaddr = FIXADDR_USER_START;
125 if (!size)
126 return;
128 fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir);
129 v = (unsigned long) alloc_bootmem_low_pages(size);
130 memcpy((void *) v , (void *) FIXADDR_USER_START, size);
131 p = __pa(v);
132 for ( ; size > 0; size -= PAGE_SIZE, vaddr += PAGE_SIZE,
133 p += PAGE_SIZE) {
134 pgd = swapper_pg_dir + pgd_index(vaddr);
135 pud = pud_offset(pgd, vaddr);
136 pmd = pmd_offset(pud, vaddr);
137 pte = pte_offset_kernel(pmd, vaddr);
138 pte_set_val(*pte, p, PAGE_READONLY);
140 #endif
143 void __init paging_init(void)
145 unsigned long zones_size[MAX_NR_ZONES], vaddr;
146 int i;
148 empty_zero_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
149 empty_bad_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
150 for (i = 0; i < ARRAY_SIZE(zones_size); i++)
151 zones_size[i] = 0;
153 zones_size[ZONE_NORMAL] = (end_iomem >> PAGE_SHIFT) -
154 (uml_physmem >> PAGE_SHIFT);
155 free_area_init(zones_size);
158 * Fixed mappings, only the page table structure has to be
159 * created - mappings will be set by set_fixmap():
161 vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
162 fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
164 fixaddr_user_init();
168 * This can't do anything because nothing in the kernel image can be freed
169 * since it's not in kernel physical memory.
172 void free_initmem(void)
176 #ifdef CONFIG_BLK_DEV_INITRD
177 void free_initrd_mem(unsigned long start, unsigned long end)
179 free_reserved_area((void *)start, (void *)end, -1, "initrd");
181 #endif
183 /* Allocate and free page tables. */
185 pgd_t *pgd_alloc(struct mm_struct *mm)
187 pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
189 if (pgd) {
190 memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
191 memcpy(pgd + USER_PTRS_PER_PGD,
192 swapper_pg_dir + USER_PTRS_PER_PGD,
193 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
195 return pgd;
198 void pgd_free(struct mm_struct *mm, pgd_t *pgd)
200 free_page((unsigned long) pgd);
203 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
205 pte_t *pte;
207 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
208 return pte;
211 pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
213 struct page *pte;
215 pte = alloc_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
216 if (!pte)
217 return NULL;
218 if (!pgtable_page_ctor(pte)) {
219 __free_page(pte);
220 return NULL;
222 return pte;
225 #ifdef CONFIG_3_LEVEL_PGTABLES
226 pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
228 pmd_t *pmd = (pmd_t *) __get_free_page(GFP_KERNEL);
230 if (pmd)
231 memset(pmd, 0, PAGE_SIZE);
233 return pmd;
235 #endif
237 void *uml_kmalloc(int size, int flags)
239 return kmalloc(size, flags);