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 show_mem(void) 46 { 47 int i, total = 0, reserved = 0; 48 int shared = 0, cached = 0; 49 struct page *page; 50 51 printk("Mem-info:\n"); 52 show_free_areas(); 53 printk("Free swap: %6ldkB\n", nr_swap_pages << (PAGE_SHIFT - 10)); 54 i = max_mapnr; 55 while (i-- > 0) { 56 if (!pfn_valid(i)) 57 continue; 58 page = pfn_to_page(i); 59 total++; 60 if (PageReserved(page)) 61 reserved++; 62 else if (PageSwapCache(page)) 63 cached++; 64 else if (page_count(page)) 65 shared += page_count(page) - 1; 66 } 67 printk("%d pages of RAM\n", total); 68 printk("%d reserved pages\n", reserved); 69 printk("%d pages shared\n", shared); 70 printk("%d pages swap cached\n", cached); 71 72 printk("%lu pages dirty\n", global_page_state(NR_FILE_DIRTY)); 73 printk("%lu pages writeback\n", global_page_state(NR_WRITEBACK)); 74 printk("%lu pages mapped\n", global_page_state(NR_FILE_MAPPED)); 75 printk("%lu pages slab\n", 76 global_page_state(NR_SLAB_RECLAIMABLE) + 77 global_page_state(NR_SLAB_UNRECLAIMABLE)); 78 printk("%lu pages pagetables\n", global_page_state(NR_PAGETABLE)); 79 } 80 81 static void __init setup_ro_region(void) 82 { 83 pgd_t *pgd; 84 pmd_t *pmd; 85 pte_t *pte; 86 pte_t new_pte; 87 unsigned long address, end; 88 89 address = ((unsigned long)&_stext) & PAGE_MASK; 90 end = PFN_ALIGN((unsigned long)&_eshared); 91 92 for (; address < end; address += PAGE_SIZE) { 93 pgd = pgd_offset_k(address); 94 pmd = pmd_offset(pgd, address); 95 pte = pte_offset_kernel(pmd, address); 96 new_pte = mk_pte_phys(address, __pgprot(_PAGE_RO)); 97 *pte = new_pte; 98 } 99 } 100 101 /* 102 * paging_init() sets up the page tables 103 */ 104 void __init paging_init(void) 105 { 106 pgd_t *pg_dir; 107 int i; 108 unsigned long pgdir_k; 109 static const int ssm_mask = 0x04000000L; 110 unsigned long max_zone_pfns[MAX_NR_ZONES]; 111 112 pg_dir = swapper_pg_dir; 113 114 #ifdef CONFIG_64BIT 115 pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERN_REGION_TABLE; 116 for (i = 0; i < PTRS_PER_PGD; i++) 117 pgd_clear_kernel(pg_dir + i); 118 #else 119 pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE; 120 for (i = 0; i < PTRS_PER_PGD; i++) 121 pmd_clear_kernel((pmd_t *)(pg_dir + i)); 122 #endif 123 vmem_map_init(); 124 setup_ro_region(); 125 126 S390_lowcore.kernel_asce = pgdir_k; 127 128 /* enable virtual mapping in kernel mode */ 129 __ctl_load(pgdir_k, 1, 1); 130 __ctl_load(pgdir_k, 7, 7); 131 __ctl_load(pgdir_k, 13, 13); 132 __raw_local_irq_ssm(ssm_mask); 133 134 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 135 #ifdef CONFIG_ZONE_DMA 136 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 137 #endif 138 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 139 free_area_init_nodes(max_zone_pfns); 140 } 141 142 void __init mem_init(void) 143 { 144 unsigned long codesize, reservedpages, datasize, initsize; 145 146 max_mapnr = num_physpages = max_low_pfn; 147 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 148 149 /* clear the zero-page */ 150 memset(empty_zero_page, 0, PAGE_SIZE); 151 152 /* this will put all low memory onto the freelists */ 153 totalram_pages += free_all_bootmem(); 154 155 reservedpages = 0; 156 157 codesize = (unsigned long) &_etext - (unsigned long) &_text; 158 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 159 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 160 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n", 161 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 162 max_mapnr << (PAGE_SHIFT-10), 163 codesize >> 10, 164 reservedpages << (PAGE_SHIFT-10), 165 datasize >>10, 166 initsize >> 10); 167 printk("Write protected kernel read-only data: %#lx - %#lx\n", 168 (unsigned long)&_stext, 169 PFN_ALIGN((unsigned long)&_eshared) - 1); 170 } 171 172 void free_initmem(void) 173 { 174 unsigned long addr; 175 176 addr = (unsigned long)(&__init_begin); 177 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) { 178 ClearPageReserved(virt_to_page(addr)); 179 init_page_count(virt_to_page(addr)); 180 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE); 181 free_page(addr); 182 totalram_pages++; 183 } 184 printk ("Freeing unused kernel memory: %ldk freed\n", 185 ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10); 186 } 187 188 #ifdef CONFIG_BLK_DEV_INITRD 189 void free_initrd_mem(unsigned long start, unsigned long end) 190 { 191 if (start < end) 192 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); 193 for (; start < end; start += PAGE_SIZE) { 194 ClearPageReserved(virt_to_page(start)); 195 init_page_count(virt_to_page(start)); 196 free_page(start); 197 totalram_pages++; 198 } 199 } 200 #endif 201