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 default: 75 order = 5; 76 break; 77 } 78 /* Limit number of empty zero pages for small memory sizes */ 79 if (order > 2 && totalram_pages <= 16384) 80 order = 2; 81 82 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 83 if (!empty_zero_page) 84 panic("Out of memory in setup_zero_pages"); 85 86 page = virt_to_page((void *) empty_zero_page); 87 split_page(page, order); 88 for (i = 1 << order; i > 0; i--) { 89 mark_page_reserved(page); 90 page++; 91 } 92 93 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 94 } 95 96 /* 97 * paging_init() sets up the page tables 98 */ 99 void __init paging_init(void) 100 { 101 unsigned long max_zone_pfns[MAX_NR_ZONES]; 102 unsigned long pgd_type, asce_bits; 103 104 init_mm.pgd = swapper_pg_dir; 105 #ifdef CONFIG_64BIT 106 if (VMALLOC_END > (1UL << 42)) { 107 asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH; 108 pgd_type = _REGION2_ENTRY_EMPTY; 109 } else { 110 asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 111 pgd_type = _REGION3_ENTRY_EMPTY; 112 } 113 #else 114 asce_bits = _ASCE_TABLE_LENGTH; 115 pgd_type = _SEGMENT_ENTRY_EMPTY; 116 #endif 117 S390_lowcore.kernel_asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; 118 clear_table((unsigned long *) init_mm.pgd, pgd_type, 119 sizeof(unsigned long)*2048); 120 vmem_map_init(); 121 122 /* enable virtual mapping in kernel mode */ 123 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 124 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 125 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 126 arch_local_irq_restore(4UL << (BITS_PER_LONG - 8)); 127 128 sparse_memory_present_with_active_regions(MAX_NUMNODES); 129 sparse_init(); 130 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 131 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 132 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 133 free_area_init_nodes(max_zone_pfns); 134 } 135 136 void __init mem_init(void) 137 { 138 if (MACHINE_HAS_TLB_LC) 139 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); 140 cpumask_set_cpu(0, mm_cpumask(&init_mm)); 141 atomic_set(&init_mm.context.attach_count, 1); 142 143 max_mapnr = max_low_pfn; 144 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 145 146 /* Setup guest page hinting */ 147 cmma_init(); 148 149 /* this will put all low memory onto the freelists */ 150 free_all_bootmem(); 151 setup_zero_pages(); /* Setup zeroed pages. */ 152 153 mem_init_print_info(NULL); 154 printk("Write protected kernel read-only data: %#lx - %#lx\n", 155 (unsigned long)&_stext, 156 PFN_ALIGN((unsigned long)&_eshared) - 1); 157 } 158 159 void free_initmem(void) 160 { 161 free_initmem_default(POISON_FREE_INITMEM); 162 } 163 164 #ifdef CONFIG_BLK_DEV_INITRD 165 void __init free_initrd_mem(unsigned long start, unsigned long end) 166 { 167 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM, 168 "initrd"); 169 } 170 #endif 171 172 #ifdef CONFIG_MEMORY_HOTPLUG 173 int arch_add_memory(int nid, u64 start, u64 size) 174 { 175 unsigned long zone_start_pfn, zone_end_pfn, nr_pages; 176 unsigned long start_pfn = PFN_DOWN(start); 177 unsigned long size_pages = PFN_DOWN(size); 178 struct zone *zone; 179 int rc; 180 181 rc = vmem_add_mapping(start, size); 182 if (rc) 183 return rc; 184 for_each_zone(zone) { 185 if (zone_idx(zone) != ZONE_MOVABLE) { 186 /* Add range within existing zone limits */ 187 zone_start_pfn = zone->zone_start_pfn; 188 zone_end_pfn = zone->zone_start_pfn + 189 zone->spanned_pages; 190 } else { 191 /* Add remaining range to ZONE_MOVABLE */ 192 zone_start_pfn = start_pfn; 193 zone_end_pfn = start_pfn + size_pages; 194 } 195 if (start_pfn < zone_start_pfn || start_pfn >= zone_end_pfn) 196 continue; 197 nr_pages = (start_pfn + size_pages > zone_end_pfn) ? 198 zone_end_pfn - start_pfn : size_pages; 199 rc = __add_pages(nid, zone, start_pfn, nr_pages); 200 if (rc) 201 break; 202 start_pfn += nr_pages; 203 size_pages -= nr_pages; 204 if (!size_pages) 205 break; 206 } 207 if (rc) 208 vmem_remove_mapping(start, size); 209 return rc; 210 } 211 212 unsigned long memory_block_size_bytes(void) 213 { 214 /* 215 * Make sure the memory block size is always greater 216 * or equal than the memory increment size. 217 */ 218 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp_get_rzm()); 219 } 220 221 #ifdef CONFIG_MEMORY_HOTREMOVE 222 int arch_remove_memory(u64 start, u64 size) 223 { 224 /* 225 * There is no hardware or firmware interface which could trigger a 226 * hot memory remove on s390. So there is nothing that needs to be 227 * implemented. 228 */ 229 return -EBUSY; 230 } 231 #endif 232 #endif /* CONFIG_MEMORY_HOTPLUG */ 233