1 /* 2 * S390 version 3 * Copyright IBM Corp. 1999 4 * Author(s): Hartmut Penner (hp@de.ibm.com) 5 * 6 * Derived from "arch/i386/mm/init.c" 7 * Copyright (C) 1995 Linus Torvalds 8 */ 9 10 #include <linux/signal.h> 11 #include <linux/sched.h> 12 #include <linux/kernel.h> 13 #include <linux/errno.h> 14 #include <linux/string.h> 15 #include <linux/types.h> 16 #include <linux/ptrace.h> 17 #include <linux/mman.h> 18 #include <linux/mm.h> 19 #include <linux/swap.h> 20 #include <linux/smp.h> 21 #include <linux/init.h> 22 #include <linux/pagemap.h> 23 #include <linux/bootmem.h> 24 #include <linux/pfn.h> 25 #include <linux/poison.h> 26 #include <linux/initrd.h> 27 #include <linux/export.h> 28 #include <linux/gfp.h> 29 #include <asm/processor.h> 30 #include <asm/uaccess.h> 31 #include <asm/pgtable.h> 32 #include <asm/pgalloc.h> 33 #include <asm/dma.h> 34 #include <asm/lowcore.h> 35 #include <asm/tlb.h> 36 #include <asm/tlbflush.h> 37 #include <asm/sections.h> 38 #include <asm/ctl_reg.h> 39 40 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE))); 41 42 unsigned long empty_zero_page, zero_page_mask; 43 EXPORT_SYMBOL(empty_zero_page); 44 45 static unsigned long setup_zero_pages(void) 46 { 47 struct cpuid cpu_id; 48 unsigned int order; 49 unsigned long size; 50 struct page *page; 51 int i; 52 53 get_cpu_id(&cpu_id); 54 switch (cpu_id.machine) { 55 case 0x9672: /* g5 */ 56 case 0x2064: /* z900 */ 57 case 0x2066: /* z900 */ 58 case 0x2084: /* z990 */ 59 case 0x2086: /* z990 */ 60 case 0x2094: /* z9-109 */ 61 case 0x2096: /* z9-109 */ 62 order = 0; 63 break; 64 case 0x2097: /* z10 */ 65 case 0x2098: /* z10 */ 66 default: 67 order = 2; 68 break; 69 } 70 71 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 72 if (!empty_zero_page) 73 panic("Out of memory in setup_zero_pages"); 74 75 page = virt_to_page((void *) empty_zero_page); 76 split_page(page, order); 77 for (i = 1 << order; i > 0; i--) { 78 SetPageReserved(page); 79 page++; 80 } 81 82 size = PAGE_SIZE << order; 83 zero_page_mask = (size - 1) & PAGE_MASK; 84 85 return 1UL << order; 86 } 87 88 /* 89 * paging_init() sets up the page tables 90 */ 91 void __init paging_init(void) 92 { 93 unsigned long max_zone_pfns[MAX_NR_ZONES]; 94 unsigned long pgd_type, asce_bits; 95 96 init_mm.pgd = swapper_pg_dir; 97 #ifdef CONFIG_64BIT 98 if (VMALLOC_END > (1UL << 42)) { 99 asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH; 100 pgd_type = _REGION2_ENTRY_EMPTY; 101 } else { 102 asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 103 pgd_type = _REGION3_ENTRY_EMPTY; 104 } 105 #else 106 asce_bits = _ASCE_TABLE_LENGTH; 107 pgd_type = _SEGMENT_ENTRY_EMPTY; 108 #endif 109 S390_lowcore.kernel_asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; 110 clear_table((unsigned long *) init_mm.pgd, pgd_type, 111 sizeof(unsigned long)*2048); 112 vmem_map_init(); 113 114 /* enable virtual mapping in kernel mode */ 115 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 116 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 117 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 118 arch_local_irq_restore(4UL << (BITS_PER_LONG - 8)); 119 120 atomic_set(&init_mm.context.attach_count, 1); 121 122 sparse_memory_present_with_active_regions(MAX_NUMNODES); 123 sparse_init(); 124 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 125 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 126 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 127 free_area_init_nodes(max_zone_pfns); 128 fault_init(); 129 } 130 131 void __init mem_init(void) 132 { 133 unsigned long codesize, reservedpages, datasize, initsize; 134 135 max_mapnr = num_physpages = max_low_pfn; 136 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 137 138 /* Setup guest page hinting */ 139 cmma_init(); 140 141 /* this will put all low memory onto the freelists */ 142 totalram_pages += free_all_bootmem(); 143 totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */ 144 145 reservedpages = 0; 146 147 codesize = (unsigned long) &_etext - (unsigned long) &_text; 148 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 149 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 150 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n", 151 nr_free_pages() << (PAGE_SHIFT-10), 152 max_mapnr << (PAGE_SHIFT-10), 153 codesize >> 10, 154 reservedpages << (PAGE_SHIFT-10), 155 datasize >>10, 156 initsize >> 10); 157 printk("Write protected kernel read-only data: %#lx - %#lx\n", 158 (unsigned long)&_stext, 159 PFN_ALIGN((unsigned long)&_eshared) - 1); 160 } 161 162 #ifdef CONFIG_DEBUG_PAGEALLOC 163 void kernel_map_pages(struct page *page, int numpages, int enable) 164 { 165 pgd_t *pgd; 166 pud_t *pud; 167 pmd_t *pmd; 168 pte_t *pte; 169 unsigned long address; 170 int i; 171 172 for (i = 0; i < numpages; i++) { 173 address = page_to_phys(page + i); 174 pgd = pgd_offset_k(address); 175 pud = pud_offset(pgd, address); 176 pmd = pmd_offset(pud, address); 177 pte = pte_offset_kernel(pmd, address); 178 if (!enable) { 179 __ptep_ipte(address, pte); 180 pte_val(*pte) = _PAGE_TYPE_EMPTY; 181 continue; 182 } 183 *pte = mk_pte_phys(address, __pgprot(_PAGE_TYPE_RW)); 184 /* Flush cpu write queue. */ 185 mb(); 186 } 187 } 188 #endif 189 190 void free_init_pages(char *what, unsigned long begin, unsigned long end) 191 { 192 unsigned long addr = begin; 193 194 if (begin >= end) 195 return; 196 for (; addr < end; addr += PAGE_SIZE) { 197 ClearPageReserved(virt_to_page(addr)); 198 init_page_count(virt_to_page(addr)); 199 memset((void *)(addr & PAGE_MASK), POISON_FREE_INITMEM, 200 PAGE_SIZE); 201 free_page(addr); 202 totalram_pages++; 203 } 204 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); 205 } 206 207 void free_initmem(void) 208 { 209 free_init_pages("unused kernel memory", 210 (unsigned long)&__init_begin, 211 (unsigned long)&__init_end); 212 } 213 214 #ifdef CONFIG_BLK_DEV_INITRD 215 void free_initrd_mem(unsigned long start, unsigned long end) 216 { 217 free_init_pages("initrd memory", start, end); 218 } 219 #endif 220 221 #ifdef CONFIG_MEMORY_HOTPLUG 222 int arch_add_memory(int nid, u64 start, u64 size) 223 { 224 unsigned long zone_start_pfn, zone_end_pfn, nr_pages; 225 unsigned long start_pfn = PFN_DOWN(start); 226 unsigned long size_pages = PFN_DOWN(size); 227 struct zone *zone; 228 int rc; 229 230 rc = vmem_add_mapping(start, size); 231 if (rc) 232 return rc; 233 for_each_zone(zone) { 234 if (zone_idx(zone) != ZONE_MOVABLE) { 235 /* Add range within existing zone limits */ 236 zone_start_pfn = zone->zone_start_pfn; 237 zone_end_pfn = zone->zone_start_pfn + 238 zone->spanned_pages; 239 } else { 240 /* Add remaining range to ZONE_MOVABLE */ 241 zone_start_pfn = start_pfn; 242 zone_end_pfn = start_pfn + size_pages; 243 } 244 if (start_pfn < zone_start_pfn || start_pfn >= zone_end_pfn) 245 continue; 246 nr_pages = (start_pfn + size_pages > zone_end_pfn) ? 247 zone_end_pfn - start_pfn : size_pages; 248 rc = __add_pages(nid, zone, start_pfn, nr_pages); 249 if (rc) 250 break; 251 start_pfn += nr_pages; 252 size_pages -= nr_pages; 253 if (!size_pages) 254 break; 255 } 256 if (rc) 257 vmem_remove_mapping(start, size); 258 return rc; 259 } 260 #endif /* CONFIG_MEMORY_HOTPLUG */ 261