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 <linux/export.h> 30 #include <linux/gfp.h> 31 #include <asm/processor.h> 32 #include <asm/system.h> 33 #include <asm/uaccess.h> 34 #include <asm/pgtable.h> 35 #include <asm/pgalloc.h> 36 #include <asm/dma.h> 37 #include <asm/lowcore.h> 38 #include <asm/tlb.h> 39 #include <asm/tlbflush.h> 40 #include <asm/sections.h> 41 42 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE))); 43 44 unsigned long empty_zero_page, zero_page_mask; 45 EXPORT_SYMBOL(empty_zero_page); 46 47 static unsigned long setup_zero_pages(void) 48 { 49 struct cpuid cpu_id; 50 unsigned int order; 51 unsigned long size; 52 struct page *page; 53 int i; 54 55 get_cpu_id(&cpu_id); 56 switch (cpu_id.machine) { 57 case 0x9672: /* g5 */ 58 case 0x2064: /* z900 */ 59 case 0x2066: /* z900 */ 60 case 0x2084: /* z990 */ 61 case 0x2086: /* z990 */ 62 case 0x2094: /* z9-109 */ 63 case 0x2096: /* z9-109 */ 64 order = 0; 65 break; 66 case 0x2097: /* z10 */ 67 case 0x2098: /* z10 */ 68 default: 69 order = 2; 70 break; 71 } 72 73 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 74 if (!empty_zero_page) 75 panic("Out of memory in setup_zero_pages"); 76 77 page = virt_to_page((void *) empty_zero_page); 78 split_page(page, order); 79 for (i = 1 << order; i > 0; i--) { 80 SetPageReserved(page); 81 page++; 82 } 83 84 size = PAGE_SIZE << order; 85 zero_page_mask = (size - 1) & PAGE_MASK; 86 87 return 1UL << order; 88 } 89 90 /* 91 * paging_init() sets up the page tables 92 */ 93 void __init paging_init(void) 94 { 95 unsigned long max_zone_pfns[MAX_NR_ZONES]; 96 unsigned long pgd_type, asce_bits; 97 98 init_mm.pgd = swapper_pg_dir; 99 #ifdef CONFIG_64BIT 100 if (VMALLOC_END > (1UL << 42)) { 101 asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH; 102 pgd_type = _REGION2_ENTRY_EMPTY; 103 } else { 104 asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 105 pgd_type = _REGION3_ENTRY_EMPTY; 106 } 107 #else 108 asce_bits = _ASCE_TABLE_LENGTH; 109 pgd_type = _SEGMENT_ENTRY_EMPTY; 110 #endif 111 S390_lowcore.kernel_asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; 112 clear_table((unsigned long *) init_mm.pgd, pgd_type, 113 sizeof(unsigned long)*2048); 114 vmem_map_init(); 115 116 /* enable virtual mapping in kernel mode */ 117 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 118 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 119 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 120 arch_local_irq_restore(4UL << (BITS_PER_LONG - 8)); 121 122 atomic_set(&init_mm.context.attach_count, 1); 123 124 sparse_memory_present_with_active_regions(MAX_NUMNODES); 125 sparse_init(); 126 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 127 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 128 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 129 free_area_init_nodes(max_zone_pfns); 130 fault_init(); 131 } 132 133 void __init mem_init(void) 134 { 135 unsigned long codesize, reservedpages, datasize, initsize; 136 137 max_mapnr = num_physpages = max_low_pfn; 138 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 139 140 /* Setup guest page hinting */ 141 cmma_init(); 142 143 /* this will put all low memory onto the freelists */ 144 totalram_pages += free_all_bootmem(); 145 totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */ 146 147 reservedpages = 0; 148 149 codesize = (unsigned long) &_etext - (unsigned long) &_text; 150 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 151 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 152 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n", 153 nr_free_pages() << (PAGE_SHIFT-10), 154 max_mapnr << (PAGE_SHIFT-10), 155 codesize >> 10, 156 reservedpages << (PAGE_SHIFT-10), 157 datasize >>10, 158 initsize >> 10); 159 printk("Write protected kernel read-only data: %#lx - %#lx\n", 160 (unsigned long)&_stext, 161 PFN_ALIGN((unsigned long)&_eshared) - 1); 162 } 163 164 #ifdef CONFIG_DEBUG_PAGEALLOC 165 void kernel_map_pages(struct page *page, int numpages, int enable) 166 { 167 pgd_t *pgd; 168 pud_t *pud; 169 pmd_t *pmd; 170 pte_t *pte; 171 unsigned long address; 172 int i; 173 174 for (i = 0; i < numpages; i++) { 175 address = page_to_phys(page + i); 176 pgd = pgd_offset_k(address); 177 pud = pud_offset(pgd, address); 178 pmd = pmd_offset(pud, address); 179 pte = pte_offset_kernel(pmd, address); 180 if (!enable) { 181 __ptep_ipte(address, pte); 182 pte_val(*pte) = _PAGE_TYPE_EMPTY; 183 continue; 184 } 185 *pte = mk_pte_phys(address, __pgprot(_PAGE_TYPE_RW)); 186 /* Flush cpu write queue. */ 187 mb(); 188 } 189 } 190 #endif 191 192 void free_init_pages(char *what, unsigned long begin, unsigned long end) 193 { 194 unsigned long addr = begin; 195 196 if (begin >= end) 197 return; 198 for (; addr < end; addr += PAGE_SIZE) { 199 ClearPageReserved(virt_to_page(addr)); 200 init_page_count(virt_to_page(addr)); 201 memset((void *)(addr & PAGE_MASK), POISON_FREE_INITMEM, 202 PAGE_SIZE); 203 free_page(addr); 204 totalram_pages++; 205 } 206 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); 207 } 208 209 void free_initmem(void) 210 { 211 free_init_pages("unused kernel memory", 212 (unsigned long)&__init_begin, 213 (unsigned long)&__init_end); 214 } 215 216 #ifdef CONFIG_BLK_DEV_INITRD 217 void free_initrd_mem(unsigned long start, unsigned long end) 218 { 219 free_init_pages("initrd memory", start, end); 220 } 221 #endif 222 223 #ifdef CONFIG_MEMORY_HOTPLUG 224 int arch_add_memory(int nid, u64 start, u64 size) 225 { 226 struct pglist_data *pgdat; 227 struct zone *zone; 228 int rc; 229 230 pgdat = NODE_DATA(nid); 231 zone = pgdat->node_zones + ZONE_MOVABLE; 232 rc = vmem_add_mapping(start, size); 233 if (rc) 234 return rc; 235 rc = __add_pages(nid, zone, PFN_DOWN(start), PFN_DOWN(size)); 236 if (rc) 237 vmem_remove_mapping(start, size); 238 return rc; 239 } 240 #endif /* CONFIG_MEMORY_HOTPLUG */ 241