5 * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
6 * Author(s): Hartmut Penner (hp@de.ibm.com)
8 * Derived from "arch/i386/mm/init.c"
9 * Copyright (C) 1995 Linus Torvalds
12 #include <linux/signal.h>
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/string.h>
17 #include <linux/types.h>
18 #include <linux/ptrace.h>
19 #include <linux/mman.h>
21 #include <linux/swap.h>
22 #include <linux/smp.h>
23 #include <linux/init.h>
24 #include <linux/pagemap.h>
25 #include <linux/bootmem.h>
26 #include <linux/pfn.h>
28 #include <asm/processor.h>
29 #include <asm/system.h>
30 #include <asm/uaccess.h>
31 #include <asm/pgtable.h>
32 #include <asm/pgalloc.h>
34 #include <asm/lowcore.h>
36 #include <asm/tlbflush.h>
37 #include <asm/sections.h>
39 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
41 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));
42 char empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
44 void diag10(unsigned long addr)
46 if (addr >= 0x7ff00000)
53 ".section __ex_table,\"a\"\n"
62 ".section __ex_table,\"a\"\n"
72 int i, total = 0, reserved = 0;
73 int shared = 0, cached = 0;
75 printk("Mem-info:\n");
77 printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
81 if (PageReserved(mem_map+i))
83 else if (PageSwapCache(mem_map+i))
85 else if (page_count(mem_map+i))
86 shared += page_count(mem_map+i) - 1;
88 printk("%d pages of RAM\n",total);
89 printk("%d reserved pages\n",reserved);
90 printk("%d pages shared\n",shared);
91 printk("%d pages swap cached\n",cached);
94 extern unsigned long __initdata zholes_size[];
96 * paging_init() sets up the page tables
100 void __init paging_init(void)
107 unsigned long pfn = 0;
108 unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE;
109 static const int ssm_mask = 0x04000000L;
110 unsigned long ro_start_pfn, ro_end_pfn;
112 ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata);
113 ro_end_pfn = PFN_UP((unsigned long)&__end_rodata);
115 /* unmap whole virtual address space */
117 pg_dir = swapper_pg_dir;
119 for (i=0;i<KERNEL_PGD_PTRS;i++)
120 pmd_clear((pmd_t*)pg_dir++);
123 * map whole physical memory to virtual memory (identity mapping)
126 pg_dir = swapper_pg_dir;
128 while (pfn < max_low_pfn) {
130 * pg_table is physical at this point
132 pg_table = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
134 pg_dir->pgd0 = (_PAGE_TABLE | __pa(pg_table));
135 pg_dir->pgd1 = (_PAGE_TABLE | (__pa(pg_table)+1024));
136 pg_dir->pgd2 = (_PAGE_TABLE | (__pa(pg_table)+2048));
137 pg_dir->pgd3 = (_PAGE_TABLE | (__pa(pg_table)+3072));
140 for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) {
141 if (pfn >= ro_start_pfn && pfn < ro_end_pfn)
142 pte = pfn_pte(pfn, __pgprot(_PAGE_RO));
144 pte = pfn_pte(pfn, PAGE_KERNEL);
145 if (pfn >= max_low_pfn)
146 pte_clear(&init_mm, 0, &pte);
147 set_pte(pg_table, pte);
152 S390_lowcore.kernel_asce = pgdir_k;
154 /* enable virtual mapping in kernel mode */
155 __asm__ __volatile__(" LCTL 1,1,%0\n"
159 : : "m" (pgdir_k), "m" (ssm_mask));
164 unsigned long zones_size[MAX_NR_ZONES];
166 memset(zones_size, 0, sizeof(zones_size));
167 zones_size[ZONE_DMA] = max_low_pfn;
168 free_area_init_node(0, &contig_page_data, zones_size,
169 __pa(PAGE_OFFSET) >> PAGE_SHIFT,
175 #else /* CONFIG_64BIT */
177 void __init paging_init(void)
184 unsigned long pfn = 0;
185 unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) |
187 static const int ssm_mask = 0x04000000L;
188 unsigned long zones_size[MAX_NR_ZONES];
189 unsigned long dma_pfn, high_pfn;
190 unsigned long ro_start_pfn, ro_end_pfn;
192 memset(zones_size, 0, sizeof(zones_size));
193 dma_pfn = MAX_DMA_ADDRESS >> PAGE_SHIFT;
194 high_pfn = max_low_pfn;
195 ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata);
196 ro_end_pfn = PFN_UP((unsigned long)&__end_rodata);
198 if (dma_pfn > high_pfn)
199 zones_size[ZONE_DMA] = high_pfn;
201 zones_size[ZONE_DMA] = dma_pfn;
202 zones_size[ZONE_NORMAL] = high_pfn - dma_pfn;
205 /* Initialize mem_map[]. */
206 free_area_init_node(0, &contig_page_data, zones_size,
207 __pa(PAGE_OFFSET) >> PAGE_SHIFT, zholes_size);
210 * map whole physical memory to virtual memory (identity mapping)
213 pg_dir = swapper_pg_dir;
215 for (i = 0 ; i < PTRS_PER_PGD ; i++,pg_dir++) {
217 if (pfn >= max_low_pfn) {
222 pm_dir = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE*4);
223 pgd_populate(&init_mm, pg_dir, pm_dir);
225 for (j = 0 ; j < PTRS_PER_PMD ; j++,pm_dir++) {
226 if (pfn >= max_low_pfn) {
231 pt_dir = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
232 pmd_populate_kernel(&init_mm, pm_dir, pt_dir);
234 for (k = 0 ; k < PTRS_PER_PTE ; k++,pt_dir++) {
235 if (pfn >= ro_start_pfn && pfn < ro_end_pfn)
236 pte = pfn_pte(pfn, __pgprot(_PAGE_RO));
238 pte = pfn_pte(pfn, PAGE_KERNEL);
239 if (pfn >= max_low_pfn) {
240 pte_clear(&init_mm, 0, &pte);
243 set_pte(pt_dir, pte);
249 S390_lowcore.kernel_asce = pgdir_k;
251 /* enable virtual mapping in kernel mode */
252 __asm__ __volatile__("lctlg 1,1,%0\n\t"
256 : :"m" (pgdir_k), "m" (ssm_mask));
262 #endif /* CONFIG_64BIT */
264 void __init mem_init(void)
266 unsigned long codesize, reservedpages, datasize, initsize;
268 max_mapnr = num_physpages = max_low_pfn;
269 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
271 /* clear the zero-page */
272 memset(empty_zero_page, 0, PAGE_SIZE);
274 /* this will put all low memory onto the freelists */
275 totalram_pages += free_all_bootmem();
279 codesize = (unsigned long) &_etext - (unsigned long) &_text;
280 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
281 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
282 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n",
283 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
284 max_mapnr << (PAGE_SHIFT-10),
286 reservedpages << (PAGE_SHIFT-10),
289 printk("Write protected kernel read-only data: %#lx - %#lx\n",
290 (unsigned long)&__start_rodata,
291 PFN_ALIGN((unsigned long)&__end_rodata) - 1);
294 void free_initmem(void)
298 addr = (unsigned long)(&__init_begin);
299 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
300 ClearPageReserved(virt_to_page(addr));
301 init_page_count(virt_to_page(addr));
305 printk ("Freeing unused kernel memory: %ldk freed\n",
306 ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10);
309 #ifdef CONFIG_BLK_DEV_INITRD
310 void free_initrd_mem(unsigned long start, unsigned long end)
313 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
314 for (; start < end; start += PAGE_SIZE) {
315 ClearPageReserved(virt_to_page(start));
316 init_page_count(virt_to_page(start));