1 /* 2 * arch/s390/mm/init.c 3 * 4 * S390 version 5 * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation 6 * Author(s): Hartmut Penner (hp@de.ibm.com) 7 * 8 * Derived from "arch/i386/mm/init.c" 9 * Copyright (C) 1995 Linus Torvalds 10 */ 11 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> 20 #include <linux/mm.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> 27 #include <linux/poison.h> 28 #include <linux/initrd.h> 29 #include <asm/processor.h> 30 #include <asm/system.h> 31 #include <asm/uaccess.h> 32 #include <asm/pgtable.h> 33 #include <asm/pgalloc.h> 34 #include <asm/dma.h> 35 #include <asm/lowcore.h> 36 #include <asm/tlb.h> 37 #include <asm/tlbflush.h> 38 #include <asm/sections.h> 39 40 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 41 42 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE))); 43 char empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); 44 45 void diag10(unsigned long addr) 46 { 47 if (addr >= 0x7ff00000) 48 return; 49 asm volatile( 50 #ifdef CONFIG_64BIT 51 " sam31\n" 52 " diag %0,%0,0x10\n" 53 "0: sam64\n" 54 #else 55 " diag %0,%0,0x10\n" 56 "0:\n" 57 #endif 58 EX_TABLE(0b,0b) 59 : : "a" (addr)); 60 } 61 62 void show_mem(void) 63 { 64 int i, total = 0, reserved = 0; 65 int shared = 0, cached = 0; 66 struct page *page; 67 68 printk("Mem-info:\n"); 69 show_free_areas(); 70 printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); 71 i = max_mapnr; 72 while (i-- > 0) { 73 if (!pfn_valid(i)) 74 continue; 75 page = pfn_to_page(i); 76 total++; 77 if (PageReserved(page)) 78 reserved++; 79 else if (PageSwapCache(page)) 80 cached++; 81 else if (page_count(page)) 82 shared += page_count(page) - 1; 83 } 84 printk("%d pages of RAM\n",total); 85 printk("%d reserved pages\n",reserved); 86 printk("%d pages shared\n",shared); 87 printk("%d pages swap cached\n",cached); 88 } 89 90 static void __init setup_ro_region(void) 91 { 92 pgd_t *pgd; 93 pmd_t *pmd; 94 pte_t *pte; 95 pte_t new_pte; 96 unsigned long address, end; 97 98 address = ((unsigned long)&_stext) & PAGE_MASK; 99 end = PFN_ALIGN((unsigned long)&_eshared); 100 101 for (; address < end; address += PAGE_SIZE) { 102 pgd = pgd_offset_k(address); 103 pmd = pmd_offset(pgd, address); 104 pte = pte_offset_kernel(pmd, address); 105 new_pte = mk_pte_phys(address, __pgprot(_PAGE_RO)); 106 *pte = new_pte; 107 } 108 } 109 110 /* 111 * paging_init() sets up the page tables 112 */ 113 void __init paging_init(void) 114 { 115 pgd_t *pg_dir; 116 int i; 117 unsigned long pgdir_k; 118 static const int ssm_mask = 0x04000000L; 119 unsigned long max_zone_pfns[MAX_NR_ZONES]; 120 121 pg_dir = swapper_pg_dir; 122 123 #ifdef CONFIG_64BIT 124 pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERN_REGION_TABLE; 125 for (i = 0; i < PTRS_PER_PGD; i++) 126 pgd_clear_kernel(pg_dir + i); 127 #else 128 pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE; 129 for (i = 0; i < PTRS_PER_PGD; i++) 130 pmd_clear_kernel((pmd_t *)(pg_dir + i)); 131 #endif 132 vmem_map_init(); 133 setup_ro_region(); 134 135 S390_lowcore.kernel_asce = pgdir_k; 136 137 /* enable virtual mapping in kernel mode */ 138 __ctl_load(pgdir_k, 1, 1); 139 __ctl_load(pgdir_k, 7, 7); 140 __ctl_load(pgdir_k, 13, 13); 141 __raw_local_irq_ssm(ssm_mask); 142 143 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 144 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 145 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 146 free_area_init_nodes(max_zone_pfns); 147 } 148 149 void __init mem_init(void) 150 { 151 unsigned long codesize, reservedpages, datasize, initsize; 152 153 max_mapnr = num_physpages = max_low_pfn; 154 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 155 156 /* clear the zero-page */ 157 memset(empty_zero_page, 0, PAGE_SIZE); 158 159 /* this will put all low memory onto the freelists */ 160 totalram_pages += free_all_bootmem(); 161 162 reservedpages = 0; 163 164 codesize = (unsigned long) &_etext - (unsigned long) &_text; 165 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 166 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 167 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n", 168 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 169 max_mapnr << (PAGE_SHIFT-10), 170 codesize >> 10, 171 reservedpages << (PAGE_SHIFT-10), 172 datasize >>10, 173 initsize >> 10); 174 printk("Write protected kernel read-only data: %#lx - %#lx\n", 175 (unsigned long)&_stext, 176 PFN_ALIGN((unsigned long)&_eshared) - 1); 177 } 178 179 void free_initmem(void) 180 { 181 unsigned long addr; 182 183 addr = (unsigned long)(&__init_begin); 184 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) { 185 ClearPageReserved(virt_to_page(addr)); 186 init_page_count(virt_to_page(addr)); 187 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE); 188 free_page(addr); 189 totalram_pages++; 190 } 191 printk ("Freeing unused kernel memory: %ldk freed\n", 192 ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10); 193 } 194 195 #ifdef CONFIG_BLK_DEV_INITRD 196 void free_initrd_mem(unsigned long start, unsigned long end) 197 { 198 if (start < end) 199 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); 200 for (; start < end; start += PAGE_SIZE) { 201 ClearPageReserved(virt_to_page(start)); 202 init_page_count(virt_to_page(start)); 203 free_page(start); 204 totalram_pages++; 205 } 206 } 207 #endif 208