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 i = max_mapnr; 54 while (i-- > 0) { 55 if (!pfn_valid(i)) 56 continue; 57 page = pfn_to_page(i); 58 total++; 59 if (PageReserved(page)) 60 reserved++; 61 else if (PageSwapCache(page)) 62 cached++; 63 else if (page_count(page)) 64 shared += page_count(page) - 1; 65 } 66 printk("%d pages of RAM\n", total); 67 printk("%d reserved pages\n", reserved); 68 printk("%d pages shared\n", shared); 69 printk("%d pages swap cached\n", cached); 70 71 printk("%lu pages dirty\n", global_page_state(NR_FILE_DIRTY)); 72 printk("%lu pages writeback\n", global_page_state(NR_WRITEBACK)); 73 printk("%lu pages mapped\n", global_page_state(NR_FILE_MAPPED)); 74 printk("%lu pages slab\n", 75 global_page_state(NR_SLAB_RECLAIMABLE) + 76 global_page_state(NR_SLAB_UNRECLAIMABLE)); 77 printk("%lu pages pagetables\n", global_page_state(NR_PAGETABLE)); 78 } 79 80 /* 81 * paging_init() sets up the page tables 82 */ 83 void __init paging_init(void) 84 { 85 static const int ssm_mask = 0x04000000L; 86 unsigned long max_zone_pfns[MAX_NR_ZONES]; 87 unsigned long pgd_type; 88 89 init_mm.pgd = swapper_pg_dir; 90 S390_lowcore.kernel_asce = __pa(init_mm.pgd) & PAGE_MASK; 91 #ifdef CONFIG_64BIT 92 /* A three level page table (4TB) is enough for the kernel space. */ 93 S390_lowcore.kernel_asce |= _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 94 pgd_type = _REGION3_ENTRY_EMPTY; 95 #else 96 S390_lowcore.kernel_asce |= _ASCE_TABLE_LENGTH; 97 pgd_type = _SEGMENT_ENTRY_EMPTY; 98 #endif 99 clear_table((unsigned long *) init_mm.pgd, pgd_type, 100 sizeof(unsigned long)*2048); 101 vmem_map_init(); 102 103 /* enable virtual mapping in kernel mode */ 104 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 105 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 106 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 107 __raw_local_irq_ssm(ssm_mask); 108 109 sparse_memory_present_with_active_regions(MAX_NUMNODES); 110 sparse_init(); 111 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 112 #ifdef CONFIG_ZONE_DMA 113 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 114 #endif 115 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 116 free_area_init_nodes(max_zone_pfns); 117 } 118 119 void __init mem_init(void) 120 { 121 unsigned long codesize, reservedpages, datasize, initsize; 122 123 max_mapnr = num_physpages = max_low_pfn; 124 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 125 126 /* clear the zero-page */ 127 memset(empty_zero_page, 0, PAGE_SIZE); 128 129 /* Setup guest page hinting */ 130 cmma_init(); 131 132 /* this will put all low memory onto the freelists */ 133 totalram_pages += free_all_bootmem(); 134 135 reservedpages = 0; 136 137 codesize = (unsigned long) &_etext - (unsigned long) &_text; 138 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 139 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 140 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n", 141 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 142 max_mapnr << (PAGE_SHIFT-10), 143 codesize >> 10, 144 reservedpages << (PAGE_SHIFT-10), 145 datasize >>10, 146 initsize >> 10); 147 printk("Write protected kernel read-only data: %#lx - %#lx\n", 148 (unsigned long)&_stext, 149 PFN_ALIGN((unsigned long)&_eshared) - 1); 150 } 151 152 #ifdef CONFIG_DEBUG_PAGEALLOC 153 void kernel_map_pages(struct page *page, int numpages, int enable) 154 { 155 pgd_t *pgd; 156 pud_t *pud; 157 pmd_t *pmd; 158 pte_t *pte; 159 unsigned long address; 160 int i; 161 162 for (i = 0; i < numpages; i++) { 163 address = page_to_phys(page + i); 164 pgd = pgd_offset_k(address); 165 pud = pud_offset(pgd, address); 166 pmd = pmd_offset(pud, address); 167 pte = pte_offset_kernel(pmd, address); 168 if (!enable) { 169 ptep_invalidate(&init_mm, address, pte); 170 continue; 171 } 172 *pte = mk_pte_phys(address, __pgprot(_PAGE_TYPE_RW)); 173 /* Flush cpu write queue. */ 174 mb(); 175 } 176 } 177 #endif 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