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 void show_mem(void) 46 { 47 unsigned long i, total = 0, reserved = 0; 48 unsigned long shared = 0, cached = 0; 49 unsigned long flags; 50 struct page *page; 51 pg_data_t *pgdat; 52 53 printk("Mem-info:\n"); 54 show_free_areas(); 55 for_each_online_pgdat(pgdat) { 56 pgdat_resize_lock(pgdat, &flags); 57 for (i = 0; i < pgdat->node_spanned_pages; i++) { 58 if (!pfn_valid(pgdat->node_start_pfn + i)) 59 continue; 60 page = pfn_to_page(pgdat->node_start_pfn + i); 61 total++; 62 if (PageReserved(page)) 63 reserved++; 64 else if (PageSwapCache(page)) 65 cached++; 66 else if (page_count(page)) 67 shared += page_count(page) - 1; 68 } 69 pgdat_resize_unlock(pgdat, &flags); 70 } 71 printk("%ld pages of RAM\n", total); 72 printk("%ld reserved pages\n", reserved); 73 printk("%ld pages shared\n", shared); 74 printk("%ld pages swap cached\n", cached); 75 } 76 77 /* 78 * paging_init() sets up the page tables 79 */ 80 void __init paging_init(void) 81 { 82 static const int ssm_mask = 0x04000000L; 83 unsigned long max_zone_pfns[MAX_NR_ZONES]; 84 unsigned long pgd_type; 85 86 init_mm.pgd = swapper_pg_dir; 87 S390_lowcore.kernel_asce = __pa(init_mm.pgd) & PAGE_MASK; 88 #ifdef CONFIG_64BIT 89 /* A three level page table (4TB) is enough for the kernel space. */ 90 S390_lowcore.kernel_asce |= _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH; 91 pgd_type = _REGION3_ENTRY_EMPTY; 92 #else 93 S390_lowcore.kernel_asce |= _ASCE_TABLE_LENGTH; 94 pgd_type = _SEGMENT_ENTRY_EMPTY; 95 #endif 96 clear_table((unsigned long *) init_mm.pgd, pgd_type, 97 sizeof(unsigned long)*2048); 98 vmem_map_init(); 99 100 /* enable virtual mapping in kernel mode */ 101 __ctl_load(S390_lowcore.kernel_asce, 1, 1); 102 __ctl_load(S390_lowcore.kernel_asce, 7, 7); 103 __ctl_load(S390_lowcore.kernel_asce, 13, 13); 104 __raw_local_irq_ssm(ssm_mask); 105 106 sparse_memory_present_with_active_regions(MAX_NUMNODES); 107 sparse_init(); 108 memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); 109 #ifdef CONFIG_ZONE_DMA 110 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS); 111 #endif 112 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 113 free_area_init_nodes(max_zone_pfns); 114 } 115 116 void __init mem_init(void) 117 { 118 unsigned long codesize, reservedpages, datasize, initsize; 119 120 max_mapnr = num_physpages = max_low_pfn; 121 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 122 123 /* clear the zero-page */ 124 memset(empty_zero_page, 0, PAGE_SIZE); 125 126 /* Setup guest page hinting */ 127 cmma_init(); 128 129 /* this will put all low memory onto the freelists */ 130 totalram_pages += free_all_bootmem(); 131 132 reservedpages = 0; 133 134 codesize = (unsigned long) &_etext - (unsigned long) &_text; 135 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 136 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 137 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n", 138 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 139 max_mapnr << (PAGE_SHIFT-10), 140 codesize >> 10, 141 reservedpages << (PAGE_SHIFT-10), 142 datasize >>10, 143 initsize >> 10); 144 printk("Write protected kernel read-only data: %#lx - %#lx\n", 145 (unsigned long)&_stext, 146 PFN_ALIGN((unsigned long)&_eshared) - 1); 147 } 148 149 #ifdef CONFIG_DEBUG_PAGEALLOC 150 void kernel_map_pages(struct page *page, int numpages, int enable) 151 { 152 pgd_t *pgd; 153 pud_t *pud; 154 pmd_t *pmd; 155 pte_t *pte; 156 unsigned long address; 157 int i; 158 159 for (i = 0; i < numpages; i++) { 160 address = page_to_phys(page + i); 161 pgd = pgd_offset_k(address); 162 pud = pud_offset(pgd, address); 163 pmd = pmd_offset(pud, address); 164 pte = pte_offset_kernel(pmd, address); 165 if (!enable) { 166 ptep_invalidate(&init_mm, address, pte); 167 continue; 168 } 169 *pte = mk_pte_phys(address, __pgprot(_PAGE_TYPE_RW)); 170 /* Flush cpu write queue. */ 171 mb(); 172 } 173 } 174 #endif 175 176 void free_initmem(void) 177 { 178 unsigned long addr; 179 180 addr = (unsigned long)(&__init_begin); 181 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) { 182 ClearPageReserved(virt_to_page(addr)); 183 init_page_count(virt_to_page(addr)); 184 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE); 185 free_page(addr); 186 totalram_pages++; 187 } 188 printk ("Freeing unused kernel memory: %ldk freed\n", 189 ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10); 190 } 191 192 #ifdef CONFIG_BLK_DEV_INITRD 193 void free_initrd_mem(unsigned long start, unsigned long end) 194 { 195 if (start < end) 196 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); 197 for (; start < end; start += PAGE_SIZE) { 198 ClearPageReserved(virt_to_page(start)); 199 init_page_count(virt_to_page(start)); 200 free_page(start); 201 totalram_pages++; 202 } 203 } 204 #endif 205 206 #ifdef CONFIG_MEMORY_HOTPLUG 207 int arch_add_memory(int nid, u64 start, u64 size) 208 { 209 struct pglist_data *pgdat; 210 struct zone *zone; 211 int rc; 212 213 pgdat = NODE_DATA(nid); 214 zone = pgdat->node_zones + ZONE_NORMAL; 215 rc = vmem_add_mapping(start, size); 216 if (rc) 217 return rc; 218 rc = __add_pages(zone, PFN_DOWN(start), PFN_DOWN(size)); 219 if (rc) 220 vmem_remove_mapping(start, size); 221 return rc; 222 } 223 #endif /* CONFIG_MEMORY_HOTPLUG */ 224