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/memory.h> 25 #include <linux/pfn.h> 26 #include <linux/poison.h> 27 #include <linux/initrd.h> 28 #include <linux/export.h> 29 #include <linux/gfp.h> 30 #include <asm/processor.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 #include <asm/ctl_reg.h> 40 #include <asm/sclp.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 EXPORT_SYMBOL(zero_page_mask); 47 48 static void __init setup_zero_pages(void) 49 { 50 struct cpuid cpu_id; 51 unsigned int order; 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 case 0x2817: /* z196 */ 69 case 0x2818: /* z196 */ 70 order = 2; 71 break; 72 case 0x2827: /* zEC12 */ 73 case 0x2828: /* zEC12 */ 74 order = 5; 75 break; 76 case 0x2964: /* z13 */ 77 default: 78 order = 7; 79 break; 80 } 81 /* Limit number of empty zero pages for small memory sizes */ 82 while (order > 2 && (totalram_pages >> 10) < (1UL << order)) 83 order--; 84 85 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 86 if (!empty_zero_page) 87 panic("Out of memory in setup_zero_pages"); 88 89 page = virt_to_page((void *) empty_zero_page); 90 split_page(page, order); 91 for (i = 1 << order; i > 0; i--) { 92 mark_page_reserved(page); 93 page++; 94 } 95 96 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 97 } 98 99 /* 100 * paging_init() sets up the page tables 101 */ 102 void __init paging_init(void) 103 { 104 unsigned long max_zone_pfns[MAX_NR_ZONES]; 105 unsigned long pgd_type, asce_bits; 106 107 init_mm.pgd = swapper_pg_dir; 108 #ifdef CONFIG_64BIT 109 if (VMALLOC_END > (1UL << 42)) { 110 asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH; 111 pgd_type = _REGION2_ENTRY_EMPTY; 112 } else { 113 asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 114 pgd_type = _REGION3_ENTRY_EMPTY; 115 } 116 #else 117 asce_bits = _ASCE_TABLE_LENGTH; 118 pgd_type = _SEGMENT_ENTRY_EMPTY; 119 #endif 120 S390_lowcore.kernel_asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; 121 clear_table((unsigned long *) init_mm.pgd, pgd_type, 122 sizeof(unsigned long)*2048); 123 vmem_map_init(); 124 125 /* enable virtual mapping in kernel mode */ 126 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 127 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 128 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 129 arch_local_irq_restore(4UL << (BITS_PER_LONG - 8)); 130 131 sparse_memory_present_with_active_regions(MAX_NUMNODES); 132 sparse_init(); 133 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 134 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 135 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 136 free_area_init_nodes(max_zone_pfns); 137 } 138 139 void __init mem_init(void) 140 { 141 if (MACHINE_HAS_TLB_LC) 142 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); 143 cpumask_set_cpu(0, mm_cpumask(&init_mm)); 144 atomic_set(&init_mm.context.attach_count, 1); 145 146 max_mapnr = max_low_pfn; 147 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 148 149 /* Setup guest page hinting */ 150 cmma_init(); 151 152 /* this will put all low memory onto the freelists */ 153 free_all_bootmem(); 154 setup_zero_pages(); /* Setup zeroed pages. */ 155 156 mem_init_print_info(NULL); 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 void free_initmem(void) 163 { 164 free_initmem_default(POISON_FREE_INITMEM); 165 } 166 167 #ifdef CONFIG_BLK_DEV_INITRD 168 void __init free_initrd_mem(unsigned long start, unsigned long end) 169 { 170 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM, 171 "initrd"); 172 } 173 #endif 174 175 #ifdef CONFIG_MEMORY_HOTPLUG 176 int arch_add_memory(int nid, u64 start, u64 size) 177 { 178 unsigned long zone_start_pfn, zone_end_pfn, nr_pages; 179 unsigned long start_pfn = PFN_DOWN(start); 180 unsigned long size_pages = PFN_DOWN(size); 181 struct zone *zone; 182 int rc; 183 184 rc = vmem_add_mapping(start, size); 185 if (rc) 186 return rc; 187 for_each_zone(zone) { 188 if (zone_idx(zone) != ZONE_MOVABLE) { 189 /* Add range within existing zone limits */ 190 zone_start_pfn = zone->zone_start_pfn; 191 zone_end_pfn = zone->zone_start_pfn + 192 zone->spanned_pages; 193 } else { 194 /* Add remaining range to ZONE_MOVABLE */ 195 zone_start_pfn = start_pfn; 196 zone_end_pfn = start_pfn + size_pages; 197 } 198 if (start_pfn < zone_start_pfn || start_pfn >= zone_end_pfn) 199 continue; 200 nr_pages = (start_pfn + size_pages > zone_end_pfn) ? 201 zone_end_pfn - start_pfn : size_pages; 202 rc = __add_pages(nid, zone, start_pfn, nr_pages); 203 if (rc) 204 break; 205 start_pfn += nr_pages; 206 size_pages -= nr_pages; 207 if (!size_pages) 208 break; 209 } 210 if (rc) 211 vmem_remove_mapping(start, size); 212 return rc; 213 } 214 215 unsigned long memory_block_size_bytes(void) 216 { 217 /* 218 * Make sure the memory block size is always greater 219 * or equal than the memory increment size. 220 */ 221 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp_get_rzm()); 222 } 223 224 #ifdef CONFIG_MEMORY_HOTREMOVE 225 int arch_remove_memory(u64 start, u64 size) 226 { 227 /* 228 * There is no hardware or firmware interface which could trigger a 229 * hot memory remove on s390. So there is nothing that needs to be 230 * implemented. 231 */ 232 return -EBUSY; 233 } 234 #endif 235 #endif /* CONFIG_MEMORY_HOTPLUG */ 236