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 <linux/memblock.h> 31 #include <asm/processor.h> 32 #include <linux/uaccess.h> 33 #include <asm/pgtable.h> 34 #include <asm/pgalloc.h> 35 #include <asm/dma.h> 36 #include <asm/lowcore.h> 37 #include <asm/tlb.h> 38 #include <asm/tlbflush.h> 39 #include <asm/sections.h> 40 #include <asm/ctl_reg.h> 41 #include <asm/sclp.h> 42 #include <asm/set_memory.h> 43 44 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir); 45 46 unsigned long empty_zero_page, zero_page_mask; 47 EXPORT_SYMBOL(empty_zero_page); 48 EXPORT_SYMBOL(zero_page_mask); 49 50 static void __init setup_zero_pages(void) 51 { 52 unsigned int order; 53 struct page *page; 54 int i; 55 56 /* Latest machines require a mapping granularity of 512KB */ 57 order = 7; 58 59 /* Limit number of empty zero pages for small memory sizes */ 60 while (order > 2 && (totalram_pages >> 10) < (1UL << order)) 61 order--; 62 63 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order); 64 if (!empty_zero_page) 65 panic("Out of memory in setup_zero_pages"); 66 67 page = virt_to_page((void *) empty_zero_page); 68 split_page(page, order); 69 for (i = 1 << order; i > 0; i--) { 70 mark_page_reserved(page); 71 page++; 72 } 73 74 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK; 75 } 76 77 /* 78 * paging_init() sets up the page tables 79 */ 80 void __init paging_init(void) 81 { 82 unsigned long max_zone_pfns[MAX_NR_ZONES]; 83 unsigned long pgd_type, asce_bits; 84 85 init_mm.pgd = swapper_pg_dir; 86 if (VMALLOC_END > (1UL << 42)) { 87 asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH; 88 pgd_type = _REGION2_ENTRY_EMPTY; 89 } else { 90 asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 91 pgd_type = _REGION3_ENTRY_EMPTY; 92 } 93 init_mm.context.asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits; 94 S390_lowcore.kernel_asce = init_mm.context.asce; 95 clear_table((unsigned long *) init_mm.pgd, pgd_type, 96 sizeof(unsigned long)*2048); 97 vmem_map_init(); 98 99 /* enable virtual mapping in kernel mode */ 100 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 101 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 102 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 103 __arch_local_irq_stosm(0x04); 104 105 sparse_memory_present_with_active_regions(MAX_NUMNODES); 106 sparse_init(); 107 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 108 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 109 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 110 free_area_init_nodes(max_zone_pfns); 111 } 112 113 void mark_rodata_ro(void) 114 { 115 unsigned long size = __end_ro_after_init - __start_ro_after_init; 116 117 set_memory_ro((unsigned long)__start_ro_after_init, size >> PAGE_SHIFT); 118 pr_info("Write protected read-only-after-init data: %luk\n", size >> 10); 119 } 120 121 void __init mem_init(void) 122 { 123 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask); 124 cpumask_set_cpu(0, mm_cpumask(&init_mm)); 125 126 set_max_mapnr(max_low_pfn); 127 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 128 129 /* Setup guest page hinting */ 130 cmma_init(); 131 132 /* this will put all low memory onto the freelists */ 133 free_all_bootmem(); 134 setup_zero_pages(); /* Setup zeroed pages. */ 135 136 mem_init_print_info(NULL); 137 } 138 139 void free_initmem(void) 140 { 141 __set_memory((unsigned long) _sinittext, 142 (_einittext - _sinittext) >> PAGE_SHIFT, 143 SET_MEMORY_RW | SET_MEMORY_NX); 144 free_initmem_default(POISON_FREE_INITMEM); 145 } 146 147 #ifdef CONFIG_BLK_DEV_INITRD 148 void __init free_initrd_mem(unsigned long start, unsigned long end) 149 { 150 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM, 151 "initrd"); 152 } 153 #endif 154 155 unsigned long memory_block_size_bytes(void) 156 { 157 /* 158 * Make sure the memory block size is always greater 159 * or equal than the memory increment size. 160 */ 161 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm); 162 } 163 164 #ifdef CONFIG_MEMORY_HOTPLUG 165 int arch_add_memory(int nid, u64 start, u64 size, bool for_device) 166 { 167 unsigned long zone_start_pfn, zone_end_pfn, nr_pages; 168 unsigned long start_pfn = PFN_DOWN(start); 169 unsigned long size_pages = PFN_DOWN(size); 170 pg_data_t *pgdat = NODE_DATA(nid); 171 struct zone *zone; 172 int rc, i; 173 174 rc = vmem_add_mapping(start, size); 175 if (rc) 176 return rc; 177 178 for (i = 0; i < MAX_NR_ZONES; i++) { 179 zone = pgdat->node_zones + i; 180 if (zone_idx(zone) != ZONE_MOVABLE) { 181 /* Add range within existing zone limits, if possible */ 182 zone_start_pfn = zone->zone_start_pfn; 183 zone_end_pfn = zone->zone_start_pfn + 184 zone->spanned_pages; 185 } else { 186 /* Add remaining range to ZONE_MOVABLE */ 187 zone_start_pfn = start_pfn; 188 zone_end_pfn = start_pfn + size_pages; 189 } 190 if (start_pfn < zone_start_pfn || start_pfn >= zone_end_pfn) 191 continue; 192 nr_pages = (start_pfn + size_pages > zone_end_pfn) ? 193 zone_end_pfn - start_pfn : size_pages; 194 rc = __add_pages(nid, zone, start_pfn, nr_pages); 195 if (rc) 196 break; 197 start_pfn += nr_pages; 198 size_pages -= nr_pages; 199 if (!size_pages) 200 break; 201 } 202 if (rc) 203 vmem_remove_mapping(start, size); 204 return rc; 205 } 206 207 #ifdef CONFIG_MEMORY_HOTREMOVE 208 int arch_remove_memory(u64 start, u64 size) 209 { 210 /* 211 * There is no hardware or firmware interface which could trigger a 212 * hot memory remove on s390. So there is nothing that needs to be 213 * implemented. 214 */ 215 return -EBUSY; 216 } 217 #endif 218 #endif /* CONFIG_MEMORY_HOTPLUG */ 219