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 47 static void __init setup_zero_pages(void) 48 { 49 struct cpuid cpu_id; 50 unsigned int order; 51 struct page *page; 52 int i; 53 54 get_cpu_id(&cpu_id); 55 switch (cpu_id.machine) { 56 case 0x9672: /* g5 */ 57 case 0x2064: /* z900 */ 58 case 0x2066: /* z900 */ 59 case 0x2084: /* z990 */ 60 case 0x2086: /* z990 */ 61 case 0x2094: /* z9-109 */ 62 case 0x2096: /* z9-109 */ 63 order = 0; 64 break; 65 case 0x2097: /* z10 */ 66 case 0x2098: /* z10 */ 67 case 0x2817: /* z196 */ 68 case 0x2818: /* z196 */ 69 order = 2; 70 break; 71 case 0x2827: /* zEC12 */ 72 default: 73 order = 5; 74 break; 75 } 76 /* Limit number of empty zero pages for small memory sizes */ 77 if (order > 2 && totalram_pages <= 16384) 78 order = 2; 79 80 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 81 if (!empty_zero_page) 82 panic("Out of memory in setup_zero_pages"); 83 84 page = virt_to_page((void *) empty_zero_page); 85 split_page(page, order); 86 for (i = 1 << order; i > 0; i--) { 87 mark_page_reserved(page); 88 page++; 89 } 90 91 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 92 } 93 94 /* 95 * paging_init() sets up the page tables 96 */ 97 void __init paging_init(void) 98 { 99 unsigned long max_zone_pfns[MAX_NR_ZONES]; 100 unsigned long pgd_type, asce_bits; 101 102 init_mm.pgd = swapper_pg_dir; 103 #ifdef CONFIG_64BIT 104 if (VMALLOC_END > (1UL << 42)) { 105 asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH; 106 pgd_type = _REGION2_ENTRY_EMPTY; 107 } else { 108 asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 109 pgd_type = _REGION3_ENTRY_EMPTY; 110 } 111 #else 112 asce_bits = _ASCE_TABLE_LENGTH; 113 pgd_type = _SEGMENT_ENTRY_EMPTY; 114 #endif 115 S390_lowcore.kernel_asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; 116 clear_table((unsigned long *) init_mm.pgd, pgd_type, 117 sizeof(unsigned long)*2048); 118 vmem_map_init(); 119 120 /* enable virtual mapping in kernel mode */ 121 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 122 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 123 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 124 arch_local_irq_restore(4UL << (BITS_PER_LONG - 8)); 125 126 atomic_set(&init_mm.context.attach_count, 1); 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 unsigned long codesize, reservedpages, datasize, initsize; 139 140 max_mapnr = num_physpages = max_low_pfn; 141 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 142 143 /* Setup guest page hinting */ 144 cmma_init(); 145 146 /* this will put all low memory onto the freelists */ 147 totalram_pages += free_all_bootmem(); 148 setup_zero_pages(); /* Setup zeroed pages. */ 149 150 reservedpages = 0; 151 152 codesize = (unsigned long) &_etext - (unsigned long) &_text; 153 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 154 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 155 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n", 156 nr_free_pages() << (PAGE_SHIFT-10), 157 max_mapnr << (PAGE_SHIFT-10), 158 codesize >> 10, 159 reservedpages << (PAGE_SHIFT-10), 160 datasize >>10, 161 initsize >> 10); 162 printk("Write protected kernel read-only data: %#lx - %#lx\n", 163 (unsigned long)&_stext, 164 PFN_ALIGN((unsigned long)&_eshared) - 1); 165 } 166 167 void free_initmem(void) 168 { 169 free_initmem_default(0); 170 } 171 172 #ifdef CONFIG_BLK_DEV_INITRD 173 void __init free_initrd_mem(unsigned long start, unsigned long end) 174 { 175 free_reserved_area(start, end, POISON_FREE_INITMEM, "initrd"); 176 } 177 #endif 178 179 #ifdef CONFIG_MEMORY_HOTPLUG 180 int arch_add_memory(int nid, u64 start, u64 size) 181 { 182 unsigned long zone_start_pfn, zone_end_pfn, nr_pages; 183 unsigned long start_pfn = PFN_DOWN(start); 184 unsigned long size_pages = PFN_DOWN(size); 185 struct zone *zone; 186 int rc; 187 188 rc = vmem_add_mapping(start, size); 189 if (rc) 190 return rc; 191 for_each_zone(zone) { 192 if (zone_idx(zone) != ZONE_MOVABLE) { 193 /* Add range within existing zone limits */ 194 zone_start_pfn = zone->zone_start_pfn; 195 zone_end_pfn = zone->zone_start_pfn + 196 zone->spanned_pages; 197 } else { 198 /* Add remaining range to ZONE_MOVABLE */ 199 zone_start_pfn = start_pfn; 200 zone_end_pfn = start_pfn + size_pages; 201 } 202 if (start_pfn < zone_start_pfn || start_pfn >= zone_end_pfn) 203 continue; 204 nr_pages = (start_pfn + size_pages > zone_end_pfn) ? 205 zone_end_pfn - start_pfn : size_pages; 206 rc = __add_pages(nid, zone, start_pfn, nr_pages); 207 if (rc) 208 break; 209 start_pfn += nr_pages; 210 size_pages -= nr_pages; 211 if (!size_pages) 212 break; 213 } 214 if (rc) 215 vmem_remove_mapping(start, size); 216 return rc; 217 } 218 219 unsigned long memory_block_size_bytes(void) 220 { 221 /* 222 * Make sure the memory block size is always greater 223 * or equal than the memory increment size. 224 */ 225 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp_get_rzm()); 226 } 227 228 #ifdef CONFIG_MEMORY_HOTREMOVE 229 int arch_remove_memory(u64 start, u64 size) 230 { 231 /* 232 * There is no hardware or firmware interface which could trigger a 233 * hot memory remove on s390. So there is nothing that needs to be 234 * implemented. 235 */ 236 return -EBUSY; 237 } 238 #endif 239 #endif /* CONFIG_MEMORY_HOTPLUG */ 240