2 * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
3 * Licensed under the GPL
6 #include "linux/stddef.h"
7 #include "linux/kernel.h"
9 #include "linux/bootmem.h"
10 #include "linux/swap.h"
11 #include "linux/highmem.h"
12 #include "linux/gfp.h"
14 #include "asm/fixmap.h"
15 #include "asm/pgalloc.h"
16 #include "user_util.h"
17 #include "kern_util.h"
20 #include "uml_uaccess.h"
22 #include "linux/types.h"
23 #include "linux/string.h"
25 #include "kern_constants.h"
27 /* Changed during early boot */
28 unsigned long *empty_zero_page = NULL;
29 unsigned long *empty_bad_page = NULL;
30 pgd_t swapper_pg_dir[PTRS_PER_PGD];
31 unsigned long long highmem;
34 static unsigned long brk_end;
36 void unmap_physmem(void)
38 os_unmap_memory((void *) brk_end, uml_reserved - brk_end);
41 static void map_cb(void *unused)
43 map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
47 static void setup_highmem(unsigned long highmem_start,
48 unsigned long highmem_len)
51 unsigned long highmem_pfn;
54 highmem_pfn = __pa(highmem_start) >> PAGE_SHIFT;
55 for(i = 0; i < highmem_len >> PAGE_SHIFT; i++){
56 page = &mem_map[highmem_pfn + i];
57 ClearPageReserved(page);
58 init_page_count(page);
66 max_low_pfn = (high_physmem - uml_physmem) >> PAGE_SHIFT;
68 /* clear the zero-page */
69 memset((void *) empty_zero_page, 0, PAGE_SIZE);
71 /* Map in the area just after the brk now that kmalloc is about
74 brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
76 initial_thread_cb(map_cb, NULL);
77 free_bootmem(__pa(brk_end), uml_reserved - brk_end);
78 uml_reserved = brk_end;
80 /* this will put all low memory onto the freelists */
81 totalram_pages = free_all_bootmem();
83 totalhigh_pages = highmem >> PAGE_SHIFT;
84 totalram_pages += totalhigh_pages;
86 num_physpages = totalram_pages;
87 max_pfn = totalram_pages;
88 printk(KERN_INFO "Memory: %luk available\n",
89 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10));
93 setup_highmem(end_iomem, highmem);
98 * Create a page table and place a pointer to it in a middle page
101 static void __init one_page_table_init(pmd_t *pmd)
103 if (pmd_none(*pmd)) {
104 pte_t *pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
105 set_pmd(pmd, __pmd(_KERNPG_TABLE +
106 (unsigned long) __pa(pte)));
107 if (pte != pte_offset_kernel(pmd, 0))
112 static void __init one_md_table_init(pud_t *pud)
114 #ifdef CONFIG_3_LEVEL_PGTABLES
115 pmd_t *pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE);
116 set_pud(pud, __pud(_KERNPG_TABLE + (unsigned long) __pa(pmd_table)));
117 if (pmd_table != pmd_offset(pud, 0))
122 static void __init fixrange_init(unsigned long start, unsigned long end,
132 i = pgd_index(vaddr);
133 j = pmd_index(vaddr);
136 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
137 pud = pud_offset(pgd, vaddr);
139 one_md_table_init(pud);
140 pmd = pmd_offset(pud, vaddr);
141 for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) {
142 one_page_table_init(pmd);
149 #ifdef CONFIG_HIGHMEM
153 #define kmap_get_fixmap_pte(vaddr) \
154 pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)),\
157 static void __init kmap_init(void)
159 unsigned long kmap_vstart;
161 /* cache the first kmap pte */
162 kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
163 kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
165 kmap_prot = PAGE_KERNEL;
168 static void init_highmem(void)
180 fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, swapper_pg_dir);
182 pgd = swapper_pg_dir + pgd_index(vaddr);
183 pud = pud_offset(pgd, vaddr);
184 pmd = pmd_offset(pud, vaddr);
185 pte = pte_offset_kernel(pmd, vaddr);
186 pkmap_page_table = pte;
190 #endif /* CONFIG_HIGHMEM */
192 static void __init fixaddr_user_init( void)
194 #ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
195 long size = FIXADDR_USER_END - FIXADDR_USER_START;
200 unsigned long paddr, vaddr = FIXADDR_USER_START;
205 fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir);
206 paddr = (unsigned long)alloc_bootmem_low_pages( size);
207 memcpy( (void *)paddr, (void *)FIXADDR_USER_START, size);
209 for ( ; size > 0; size-=PAGE_SIZE, vaddr+=PAGE_SIZE, paddr+=PAGE_SIZE){
210 pgd = swapper_pg_dir + pgd_index(vaddr);
211 pud = pud_offset(pgd, vaddr);
212 pmd = pmd_offset(pud, vaddr);
213 pte = pte_offset_kernel(pmd, vaddr);
214 pte_set_val( (*pte), paddr, PAGE_READONLY);
219 void paging_init(void)
221 unsigned long zones_size[MAX_NR_ZONES], vaddr;
224 empty_zero_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
225 empty_bad_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
226 for(i = 0; i < ARRAY_SIZE(zones_size); i++)
229 zones_size[ZONE_DMA] = (end_iomem >> PAGE_SHIFT) - (uml_physmem >> PAGE_SHIFT);
230 #ifdef CONFIG_HIGHMEM
231 zones_size[ZONE_HIGHMEM] = highmem >> PAGE_SHIFT;
233 free_area_init(zones_size);
236 * Fixed mappings, only the page table structure has to be
237 * created - mappings will be set by set_fixmap():
239 vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
240 fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
244 #ifdef CONFIG_HIGHMEM
249 struct page *arch_validate(struct page *page, gfp_t mask, int order)
251 unsigned long addr, zero = 0;
255 if(page == NULL) return(page);
256 if(PageHighMem(page)) return(page);
258 addr = (unsigned long) page_address(page);
259 for(i = 0; i < (1 << order); i++){
260 current->thread.fault_addr = (void *) addr;
261 if(__do_copy_to_user((void __user *) addr, &zero,
263 ¤t->thread.fault_addr,
264 ¤t->thread.fault_catcher)){
265 if(!(mask & __GFP_WAIT)) return(NULL);
271 if(i == (1 << order)) return(page);
272 page = alloc_pages(mask, order);
276 /* This can't do anything because nothing in the kernel image can be freed
277 * since it's not in kernel physical memory.
280 void free_initmem(void)
284 #ifdef CONFIG_BLK_DEV_INITRD
286 void free_initrd_mem(unsigned long start, unsigned long end)
289 printk ("Freeing initrd memory: %ldk freed\n",
290 (end - start) >> 10);
291 for (; start < end; start += PAGE_SIZE) {
292 ClearPageReserved(virt_to_page(start));
293 init_page_count(virt_to_page(start));
303 int pfn, total = 0, reserved = 0;
304 int shared = 0, cached = 0;
308 printk("Mem-info:\n");
310 printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
313 page = pfn_to_page(pfn);
315 if(PageHighMem(page))
317 if(PageReserved(page))
319 else if(PageSwapCache(page))
321 else if(page_count(page))
322 shared += page_count(page) - 1;
324 printk("%d pages of RAM\n", total);
325 printk("%d pages of HIGHMEM\n", highmem);
326 printk("%d reserved pages\n", reserved);
327 printk("%d pages shared\n", shared);
328 printk("%d pages swap cached\n", cached);
332 * Allocate and free page tables.
335 pgd_t *pgd_alloc(struct mm_struct *mm)
337 pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
340 memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
341 memcpy(pgd + USER_PTRS_PER_PGD,
342 swapper_pg_dir + USER_PTRS_PER_PGD,
343 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
348 void pgd_free(pgd_t *pgd)
350 free_page((unsigned long) pgd);
353 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
357 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
361 struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
365 pte = alloc_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
369 struct iomem_region *iomem_regions = NULL;
372 extern int parse_iomem(char *str, int *add) __init;
374 __uml_setup("iomem=", parse_iomem,
375 "iomem=<name>,<file>\n"
376 " Configure <file> as an IO memory region named <name>.\n\n"
380 * Overrides for Emacs so that we follow Linus's tabbing style.
381 * Emacs will notice this stuff at the end of the file and automatically
382 * adjust the settings for this buffer only. This must remain at the end
384 * ---------------------------------------------------------------------------
386 * c-file-style: "linux"