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 28 #include <asm/processor.h> 29 #include <asm/system.h> 30 #include <asm/uaccess.h> 31 #include <asm/pgtable.h> 32 #include <asm/pgalloc.h> 33 #include <asm/dma.h> 34 #include <asm/lowcore.h> 35 #include <asm/tlb.h> 36 #include <asm/tlbflush.h> 37 #include <asm/sections.h> 38 39 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); 40 41 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE))); 42 char empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE))); 43 44 void diag10(unsigned long addr) 45 { 46 if (addr >= 0x7ff00000) 47 return; 48 #ifdef CONFIG_64BIT 49 asm volatile ( 50 " sam31\n" 51 " diag %0,%0,0x10\n" 52 "0: sam64\n" 53 ".section __ex_table,\"a\"\n" 54 " .align 8\n" 55 " .quad 0b, 0b\n" 56 ".previous\n" 57 : : "a" (addr)); 58 #else 59 asm volatile ( 60 " diag %0,%0,0x10\n" 61 "0:\n" 62 ".section __ex_table,\"a\"\n" 63 " .align 4\n" 64 " .long 0b, 0b\n" 65 ".previous\n" 66 : : "a" (addr)); 67 #endif 68 } 69 70 void show_mem(void) 71 { 72 int i, total = 0, reserved = 0; 73 int shared = 0, cached = 0; 74 75 printk("Mem-info:\n"); 76 show_free_areas(); 77 printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); 78 i = max_mapnr; 79 while (i-- > 0) { 80 total++; 81 if (PageReserved(mem_map+i)) 82 reserved++; 83 else if (PageSwapCache(mem_map+i)) 84 cached++; 85 else if (page_count(mem_map+i)) 86 shared += page_count(mem_map+i) - 1; 87 } 88 printk("%d pages of RAM\n",total); 89 printk("%d reserved pages\n",reserved); 90 printk("%d pages shared\n",shared); 91 printk("%d pages swap cached\n",cached); 92 } 93 94 extern unsigned long __initdata zholes_size[]; 95 /* 96 * paging_init() sets up the page tables 97 */ 98 99 #ifndef CONFIG_64BIT 100 void __init paging_init(void) 101 { 102 pgd_t * pg_dir; 103 pte_t * pg_table; 104 pte_t pte; 105 int i; 106 unsigned long tmp; 107 unsigned long pfn = 0; 108 unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE; 109 static const int ssm_mask = 0x04000000L; 110 unsigned long ro_start_pfn, ro_end_pfn; 111 unsigned long zones_size[MAX_NR_ZONES]; 112 113 ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata); 114 ro_end_pfn = PFN_UP((unsigned long)&__end_rodata); 115 116 memset(zones_size, 0, sizeof(zones_size)); 117 zones_size[ZONE_DMA] = max_low_pfn; 118 free_area_init_node(0, &contig_page_data, zones_size, 119 __pa(PAGE_OFFSET) >> PAGE_SHIFT, 120 zholes_size); 121 122 /* unmap whole virtual address space */ 123 124 pg_dir = swapper_pg_dir; 125 126 for (i = 0; i < PTRS_PER_PGD; i++) 127 pmd_clear((pmd_t *) pg_dir++); 128 129 /* 130 * map whole physical memory to virtual memory (identity mapping) 131 */ 132 133 pg_dir = swapper_pg_dir; 134 135 while (pfn < max_low_pfn) { 136 /* 137 * pg_table is physical at this point 138 */ 139 pg_table = (pte_t *) alloc_bootmem_pages(PAGE_SIZE); 140 141 pmd_populate_kernel(&init_mm, (pmd_t *) pg_dir, pg_table); 142 pg_dir++; 143 144 for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) { 145 if (pfn >= ro_start_pfn && pfn < ro_end_pfn) 146 pte = pfn_pte(pfn, __pgprot(_PAGE_RO)); 147 else 148 pte = pfn_pte(pfn, PAGE_KERNEL); 149 if (pfn >= max_low_pfn) 150 pte_val(pte) = _PAGE_TYPE_EMPTY; 151 set_pte(pg_table, pte); 152 pfn++; 153 } 154 } 155 156 S390_lowcore.kernel_asce = pgdir_k; 157 158 /* enable virtual mapping in kernel mode */ 159 __asm__ __volatile__(" LCTL 1,1,%0\n" 160 " LCTL 7,7,%0\n" 161 " LCTL 13,13,%0\n" 162 " SSM %1" 163 : : "m" (pgdir_k), "m" (ssm_mask)); 164 165 local_flush_tlb(); 166 return; 167 } 168 169 #else /* CONFIG_64BIT */ 170 171 void __init paging_init(void) 172 { 173 pgd_t * pg_dir; 174 pmd_t * pm_dir; 175 pte_t * pt_dir; 176 pte_t pte; 177 int i,j,k; 178 unsigned long pfn = 0; 179 unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | 180 _KERN_REGION_TABLE; 181 static const int ssm_mask = 0x04000000L; 182 unsigned long zones_size[MAX_NR_ZONES]; 183 unsigned long dma_pfn, high_pfn; 184 unsigned long ro_start_pfn, ro_end_pfn; 185 186 memset(zones_size, 0, sizeof(zones_size)); 187 dma_pfn = MAX_DMA_ADDRESS >> PAGE_SHIFT; 188 high_pfn = max_low_pfn; 189 ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata); 190 ro_end_pfn = PFN_UP((unsigned long)&__end_rodata); 191 192 if (dma_pfn > high_pfn) 193 zones_size[ZONE_DMA] = high_pfn; 194 else { 195 zones_size[ZONE_DMA] = dma_pfn; 196 zones_size[ZONE_NORMAL] = high_pfn - dma_pfn; 197 } 198 199 /* Initialize mem_map[]. */ 200 free_area_init_node(0, &contig_page_data, zones_size, 201 __pa(PAGE_OFFSET) >> PAGE_SHIFT, zholes_size); 202 203 /* 204 * map whole physical memory to virtual memory (identity mapping) 205 */ 206 207 pg_dir = swapper_pg_dir; 208 209 for (i = 0 ; i < PTRS_PER_PGD ; i++,pg_dir++) { 210 211 if (pfn >= max_low_pfn) { 212 pgd_clear(pg_dir); 213 continue; 214 } 215 216 pm_dir = (pmd_t *) alloc_bootmem_pages(PAGE_SIZE * 4); 217 pgd_populate(&init_mm, pg_dir, pm_dir); 218 219 for (j = 0 ; j < PTRS_PER_PMD ; j++,pm_dir++) { 220 if (pfn >= max_low_pfn) { 221 pmd_clear(pm_dir); 222 continue; 223 } 224 225 pt_dir = (pte_t *) alloc_bootmem_pages(PAGE_SIZE); 226 pmd_populate_kernel(&init_mm, pm_dir, pt_dir); 227 228 for (k = 0 ; k < PTRS_PER_PTE ; k++,pt_dir++) { 229 if (pfn >= ro_start_pfn && pfn < ro_end_pfn) 230 pte = pfn_pte(pfn, __pgprot(_PAGE_RO)); 231 else 232 pte = pfn_pte(pfn, PAGE_KERNEL); 233 if (pfn >= max_low_pfn) 234 pte_val(pte) = _PAGE_TYPE_EMPTY; 235 set_pte(pt_dir, pte); 236 pfn++; 237 } 238 } 239 } 240 241 S390_lowcore.kernel_asce = pgdir_k; 242 243 /* enable virtual mapping in kernel mode */ 244 __asm__ __volatile__("lctlg 1,1,%0\n\t" 245 "lctlg 7,7,%0\n\t" 246 "lctlg 13,13,%0\n\t" 247 "ssm %1" 248 : :"m" (pgdir_k), "m" (ssm_mask)); 249 250 local_flush_tlb(); 251 252 return; 253 } 254 #endif /* CONFIG_64BIT */ 255 256 void __init mem_init(void) 257 { 258 unsigned long codesize, reservedpages, datasize, initsize; 259 260 max_mapnr = num_physpages = max_low_pfn; 261 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 262 263 /* clear the zero-page */ 264 memset(empty_zero_page, 0, PAGE_SIZE); 265 266 /* this will put all low memory onto the freelists */ 267 totalram_pages += free_all_bootmem(); 268 269 reservedpages = 0; 270 271 codesize = (unsigned long) &_etext - (unsigned long) &_text; 272 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 273 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 274 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n", 275 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 276 max_mapnr << (PAGE_SHIFT-10), 277 codesize >> 10, 278 reservedpages << (PAGE_SHIFT-10), 279 datasize >>10, 280 initsize >> 10); 281 printk("Write protected kernel read-only data: %#lx - %#lx\n", 282 (unsigned long)&__start_rodata, 283 PFN_ALIGN((unsigned long)&__end_rodata) - 1); 284 } 285 286 void free_initmem(void) 287 { 288 unsigned long addr; 289 290 addr = (unsigned long)(&__init_begin); 291 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) { 292 ClearPageReserved(virt_to_page(addr)); 293 init_page_count(virt_to_page(addr)); 294 free_page(addr); 295 totalram_pages++; 296 } 297 printk ("Freeing unused kernel memory: %ldk freed\n", 298 ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10); 299 } 300 301 #ifdef CONFIG_BLK_DEV_INITRD 302 void free_initrd_mem(unsigned long start, unsigned long end) 303 { 304 if (start < end) 305 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); 306 for (; start < end; start += PAGE_SIZE) { 307 ClearPageReserved(virt_to_page(start)); 308 init_page_count(virt_to_page(start)); 309 free_page(start); 310 totalram_pages++; 311 } 312 } 313 #endif 314