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"
23 extern char __binary_start;
25 /* Changed during early boot */
26 unsigned long *empty_zero_page = NULL;
27 unsigned long *empty_bad_page = NULL;
28 pgd_t swapper_pg_dir[1024];
29 unsigned long highmem;
32 static unsigned long brk_end;
34 void unmap_physmem(void)
36 os_unmap_memory((void *) brk_end, uml_reserved - brk_end);
39 static void map_cb(void *unused)
41 map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
45 static void setup_highmem(unsigned long highmem_start,
46 unsigned long highmem_len)
49 unsigned long highmem_pfn;
52 highmem_start_page = virt_to_page(highmem_start);
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 set_bit(PG_highmem, &page->flags);
59 set_page_count(page, 1);
69 max_low_pfn = (high_physmem - uml_physmem) >> PAGE_SHIFT;
71 highmem_start_page = phys_page(__pa(high_physmem));
74 /* clear the zero-page */
75 memset((void *) empty_zero_page, 0, PAGE_SIZE);
77 /* Map in the area just after the brk now that kmalloc is about
80 brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
82 initial_thread_cb(map_cb, NULL);
83 free_bootmem(__pa(brk_end), uml_reserved - brk_end);
84 uml_reserved = brk_end;
86 /* Fill in any hole at the start of the binary */
87 start = (unsigned long) &__binary_start;
88 if(uml_physmem != start){
89 map_memory(uml_physmem, __pa(uml_physmem), start - uml_physmem,
93 /* this will put all low memory onto the freelists */
94 totalram_pages = free_all_bootmem();
95 totalhigh_pages = highmem >> PAGE_SHIFT;
96 totalram_pages += totalhigh_pages;
97 num_physpages = totalram_pages;
98 max_pfn = totalram_pages;
99 printk(KERN_INFO "Memory: %luk available\n",
100 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10));
103 #ifdef CONFIG_HIGHMEM
104 setup_highmem(end_iomem, highmem);
108 static void __init fixrange_init(unsigned long start, unsigned long end,
118 i = pgd_index(vaddr);
119 j = pmd_index(vaddr);
122 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
124 for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) {
125 if (pmd_none(*pmd)) {
126 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
127 set_pmd(pmd, __pmd(_KERNPG_TABLE +
128 (unsigned long) __pa(pte)));
129 if (pte != pte_offset_kernel(pmd, 0))
142 #define kmap_get_fixmap_pte(vaddr) \
143 pte_offset(pmd_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr))
145 void __init kmap_init(void)
147 unsigned long kmap_vstart;
149 /* cache the first kmap pte */
150 kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
151 kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
153 kmap_prot = PAGE_KERNEL;
156 static void init_highmem(void)
167 fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, swapper_pg_dir);
169 pgd = swapper_pg_dir + pgd_index(vaddr);
170 pmd = pmd_offset(pgd, vaddr);
171 pte = pte_offset_kernel(pmd, vaddr);
172 pkmap_page_table = pte;
176 #endif /* CONFIG_HIGHMEM */
178 void paging_init(void)
180 unsigned long zones_size[MAX_NR_ZONES], vaddr;
183 empty_zero_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
184 empty_bad_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
185 for(i=0;i<sizeof(zones_size)/sizeof(zones_size[0]);i++)
187 zones_size[0] = (end_iomem >> PAGE_SHIFT) - (uml_physmem >> PAGE_SHIFT);
188 zones_size[2] = highmem >> PAGE_SHIFT;
189 free_area_init(zones_size);
192 * Fixed mappings, only the page table structure has to be
193 * created - mappings will be set by set_fixmap():
195 vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
196 fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
198 #ifdef CONFIG_HIGHMEM
203 struct page *arch_validate(struct page *page, int mask, int order)
205 unsigned long addr, zero = 0;
209 if(page == NULL) return(page);
210 if(PageHighMem(page)) return(page);
212 addr = (unsigned long) page_address(page);
213 for(i = 0; i < (1 << order); i++){
214 current->thread.fault_addr = (void *) addr;
215 if(__do_copy_to_user((void *) addr, &zero,
217 ¤t->thread.fault_addr,
218 ¤t->thread.fault_catcher)){
219 if(!(mask & __GFP_WAIT)) return(NULL);
224 if(i == (1 << order)) return(page);
225 page = alloc_pages(mask, order);
229 /* This can't do anything because nothing in the kernel image can be freed
230 * since it's not in kernel physical memory.
233 void free_initmem(void)
237 #ifdef CONFIG_BLK_DEV_INITRD
239 void free_initrd_mem(unsigned long start, unsigned long end)
242 printk ("Freeing initrd memory: %ldk freed\n",
243 (end - start) >> 10);
244 for (; start < end; start += PAGE_SIZE) {
245 ClearPageReserved(virt_to_page(start));
246 set_page_count(virt_to_page(start), 1);
256 int pfn, total = 0, reserved = 0;
257 int shared = 0, cached = 0;
261 printk("Mem-info:\n");
263 printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
266 page = pfn_to_page(pfn);
268 if(PageHighMem(page))
270 if(PageReserved(page))
272 else if(PageSwapCache(page))
274 else if(page_count(page))
275 shared += page_count(page) - 1;
277 printk("%d pages of RAM\n", total);
278 printk("%d pages of HIGHMEM\n", highmem);
279 printk("%d reserved pages\n", reserved);
280 printk("%d pages shared\n", shared);
281 printk("%d pages swap cached\n", cached);
285 * Allocate and free page tables.
288 pgd_t *pgd_alloc(struct mm_struct *mm)
290 pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
293 memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
294 memcpy(pgd + USER_PTRS_PER_PGD,
295 swapper_pg_dir + USER_PTRS_PER_PGD,
296 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
301 void pgd_free(pgd_t *pgd)
303 free_page((unsigned long) pgd);
306 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
310 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
316 struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
320 pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT, 0);
327 * Overrides for Emacs so that we follow Linus's tabbing style.
328 * Emacs will notice this stuff at the end of the file and automatically
329 * adjust the settings for this buffer only. This must remain at the end
331 * ---------------------------------------------------------------------------
333 * c-file-style: "linux"