1 /* 2 * arch/s390/mm/init.c 3 * 4 * S390 version 5 * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation 6 * Author(s): Hartmut Penner (hp@de.ibm.com) 7 * 8 * Derived from "arch/i386/mm/init.c" 9 * Copyright (C) 1995 Linus Torvalds 10 */ 11 12 #include <linux/signal.h> 13 #include <linux/sched.h> 14 #include <linux/kernel.h> 15 #include <linux/errno.h> 16 #include <linux/string.h> 17 #include <linux/types.h> 18 #include <linux/ptrace.h> 19 #include <linux/mman.h> 20 #include <linux/mm.h> 21 #include <linux/swap.h> 22 #include <linux/smp.h> 23 #include <linux/init.h> 24 #include <linux/pagemap.h> 25 #include <linux/bootmem.h> 26 #include <linux/pfn.h> 27 #include <linux/poison.h> 28 #include <linux/initrd.h> 29 #include <asm/processor.h> 30 #include <asm/system.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 40 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 41 42 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE))); 43 char empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); 44 45 /* 46 * paging_init() sets up the page tables 47 */ 48 void __init paging_init(void) 49 { 50 static const int ssm_mask = 0x04000000L; 51 unsigned long max_zone_pfns[MAX_NR_ZONES]; 52 unsigned long pgd_type; 53 54 init_mm.pgd = swapper_pg_dir; 55 S390_lowcore.kernel_asce = __pa(init_mm.pgd) & PAGE_MASK; 56 #ifdef CONFIG_64BIT 57 /* A three level page table (4TB) is enough for the kernel space. */ 58 S390_lowcore.kernel_asce |= _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 59 pgd_type = _REGION3_ENTRY_EMPTY; 60 #else 61 S390_lowcore.kernel_asce |= _ASCE_TABLE_LENGTH; 62 pgd_type = _SEGMENT_ENTRY_EMPTY; 63 #endif 64 clear_table((unsigned long *) init_mm.pgd, pgd_type, 65 sizeof(unsigned long)*2048); 66 vmem_map_init(); 67 68 /* enable virtual mapping in kernel mode */ 69 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 70 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 71 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 72 __raw_local_irq_ssm(ssm_mask); 73 74 sparse_memory_present_with_active_regions(MAX_NUMNODES); 75 sparse_init(); 76 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 77 #ifdef CONFIG_ZONE_DMA 78 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 79 #endif 80 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 81 free_area_init_nodes(max_zone_pfns); 82 } 83 84 void __init mem_init(void) 85 { 86 unsigned long codesize, reservedpages, datasize, initsize; 87 88 max_mapnr = num_physpages = max_low_pfn; 89 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 90 91 /* clear the zero-page */ 92 memset(empty_zero_page, 0, PAGE_SIZE); 93 94 /* Setup guest page hinting */ 95 cmma_init(); 96 97 /* this will put all low memory onto the freelists */ 98 totalram_pages += free_all_bootmem(); 99 100 reservedpages = 0; 101 102 codesize = (unsigned long) &_etext - (unsigned long) &_text; 103 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 104 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 105 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n", 106 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 107 max_mapnr << (PAGE_SHIFT-10), 108 codesize >> 10, 109 reservedpages << (PAGE_SHIFT-10), 110 datasize >>10, 111 initsize >> 10); 112 printk("Write protected kernel read-only data: %#lx - %#lx\n", 113 (unsigned long)&_stext, 114 PFN_ALIGN((unsigned long)&_eshared) - 1); 115 } 116 117 #ifdef CONFIG_DEBUG_PAGEALLOC 118 void kernel_map_pages(struct page *page, int numpages, int enable) 119 { 120 pgd_t *pgd; 121 pud_t *pud; 122 pmd_t *pmd; 123 pte_t *pte; 124 unsigned long address; 125 int i; 126 127 for (i = 0; i < numpages; i++) { 128 address = page_to_phys(page + i); 129 pgd = pgd_offset_k(address); 130 pud = pud_offset(pgd, address); 131 pmd = pmd_offset(pud, address); 132 pte = pte_offset_kernel(pmd, address); 133 if (!enable) { 134 ptep_invalidate(&init_mm, address, pte); 135 continue; 136 } 137 *pte = mk_pte_phys(address, __pgprot(_PAGE_TYPE_RW)); 138 /* Flush cpu write queue. */ 139 mb(); 140 } 141 } 142 #endif 143 144 void free_initmem(void) 145 { 146 unsigned long addr; 147 148 addr = (unsigned long)(&__init_begin); 149 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) { 150 ClearPageReserved(virt_to_page(addr)); 151 init_page_count(virt_to_page(addr)); 152 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE); 153 free_page(addr); 154 totalram_pages++; 155 } 156 printk ("Freeing unused kernel memory: %ldk freed\n", 157 ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10); 158 } 159 160 #ifdef CONFIG_BLK_DEV_INITRD 161 void free_initrd_mem(unsigned long start, unsigned long end) 162 { 163 if (start < end) 164 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); 165 for (; start < end; start += PAGE_SIZE) { 166 ClearPageReserved(virt_to_page(start)); 167 init_page_count(virt_to_page(start)); 168 free_page(start); 169 totalram_pages++; 170 } 171 } 172 #endif 173 174 #ifdef CONFIG_MEMORY_HOTPLUG 175 int arch_add_memory(int nid, u64 start, u64 size) 176 { 177 struct pglist_data *pgdat; 178 struct zone *zone; 179 int rc; 180 181 pgdat = NODE_DATA(nid); 182 zone = pgdat->node_zones + ZONE_MOVABLE; 183 rc = vmem_add_mapping(start, size); 184 if (rc) 185 return rc; 186 rc = __add_pages(zone, PFN_DOWN(start), PFN_DOWN(size)); 187 if (rc) 188 vmem_remove_mapping(start, size); 189 return rc; 190 } 191 #endif /* CONFIG_MEMORY_HOTPLUG */ 192