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; 111 112 ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata); 113 ro_end_pfn = PFN_UP((unsigned long)&__end_rodata); 114 115 /* unmap whole virtual address space */ 116 117 pg_dir = swapper_pg_dir; 118 119 for (i=0;i<KERNEL_PGD_PTRS;i++) 120 pmd_clear((pmd_t*)pg_dir++); 121 122 /* 123 * map whole physical memory to virtual memory (identity mapping) 124 */ 125 126 pg_dir = swapper_pg_dir; 127 128 while (pfn < max_low_pfn) { 129 /* 130 * pg_table is physical at this point 131 */ 132 pg_table = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 133 134 pg_dir->pgd0 = (_PAGE_TABLE | __pa(pg_table)); 135 pg_dir->pgd1 = (_PAGE_TABLE | (__pa(pg_table)+1024)); 136 pg_dir->pgd2 = (_PAGE_TABLE | (__pa(pg_table)+2048)); 137 pg_dir->pgd3 = (_PAGE_TABLE | (__pa(pg_table)+3072)); 138 pg_dir++; 139 140 for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) { 141 if (pfn >= ro_start_pfn && pfn < ro_end_pfn) 142 pte = pfn_pte(pfn, __pgprot(_PAGE_RO)); 143 else 144 pte = pfn_pte(pfn, PAGE_KERNEL); 145 if (pfn >= max_low_pfn) 146 pte_clear(&init_mm, 0, &pte); 147 set_pte(pg_table, pte); 148 pfn++; 149 } 150 } 151 152 S390_lowcore.kernel_asce = pgdir_k; 153 154 /* enable virtual mapping in kernel mode */ 155 __asm__ __volatile__(" LCTL 1,1,%0\n" 156 " LCTL 7,7,%0\n" 157 " LCTL 13,13,%0\n" 158 " SSM %1" 159 : : "m" (pgdir_k), "m" (ssm_mask)); 160 161 local_flush_tlb(); 162 163 { 164 unsigned long zones_size[MAX_NR_ZONES]; 165 166 memset(zones_size, 0, sizeof(zones_size)); 167 zones_size[ZONE_DMA] = max_low_pfn; 168 free_area_init_node(0, &contig_page_data, zones_size, 169 __pa(PAGE_OFFSET) >> PAGE_SHIFT, 170 zholes_size); 171 } 172 return; 173 } 174 175 #else /* CONFIG_64BIT */ 176 177 void __init paging_init(void) 178 { 179 pgd_t * pg_dir; 180 pmd_t * pm_dir; 181 pte_t * pt_dir; 182 pte_t pte; 183 int i,j,k; 184 unsigned long pfn = 0; 185 unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | 186 _KERN_REGION_TABLE; 187 static const int ssm_mask = 0x04000000L; 188 unsigned long zones_size[MAX_NR_ZONES]; 189 unsigned long dma_pfn, high_pfn; 190 unsigned long ro_start_pfn, ro_end_pfn; 191 192 memset(zones_size, 0, sizeof(zones_size)); 193 dma_pfn = MAX_DMA_ADDRESS >> PAGE_SHIFT; 194 high_pfn = max_low_pfn; 195 ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata); 196 ro_end_pfn = PFN_UP((unsigned long)&__end_rodata); 197 198 if (dma_pfn > high_pfn) 199 zones_size[ZONE_DMA] = high_pfn; 200 else { 201 zones_size[ZONE_DMA] = dma_pfn; 202 zones_size[ZONE_NORMAL] = high_pfn - dma_pfn; 203 } 204 205 /* Initialize mem_map[]. */ 206 free_area_init_node(0, &contig_page_data, zones_size, 207 __pa(PAGE_OFFSET) >> PAGE_SHIFT, zholes_size); 208 209 /* 210 * map whole physical memory to virtual memory (identity mapping) 211 */ 212 213 pg_dir = swapper_pg_dir; 214 215 for (i = 0 ; i < PTRS_PER_PGD ; i++,pg_dir++) { 216 217 if (pfn >= max_low_pfn) { 218 pgd_clear(pg_dir); 219 continue; 220 } 221 222 pm_dir = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE*4); 223 pgd_populate(&init_mm, pg_dir, pm_dir); 224 225 for (j = 0 ; j < PTRS_PER_PMD ; j++,pm_dir++) { 226 if (pfn >= max_low_pfn) { 227 pmd_clear(pm_dir); 228 continue; 229 } 230 231 pt_dir = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 232 pmd_populate_kernel(&init_mm, pm_dir, pt_dir); 233 234 for (k = 0 ; k < PTRS_PER_PTE ; k++,pt_dir++) { 235 if (pfn >= ro_start_pfn && pfn < ro_end_pfn) 236 pte = pfn_pte(pfn, __pgprot(_PAGE_RO)); 237 else 238 pte = pfn_pte(pfn, PAGE_KERNEL); 239 if (pfn >= max_low_pfn) { 240 pte_clear(&init_mm, 0, &pte); 241 continue; 242 } 243 set_pte(pt_dir, pte); 244 pfn++; 245 } 246 } 247 } 248 249 S390_lowcore.kernel_asce = pgdir_k; 250 251 /* enable virtual mapping in kernel mode */ 252 __asm__ __volatile__("lctlg 1,1,%0\n\t" 253 "lctlg 7,7,%0\n\t" 254 "lctlg 13,13,%0\n\t" 255 "ssm %1" 256 : :"m" (pgdir_k), "m" (ssm_mask)); 257 258 local_flush_tlb(); 259 260 return; 261 } 262 #endif /* CONFIG_64BIT */ 263 264 void __init mem_init(void) 265 { 266 unsigned long codesize, reservedpages, datasize, initsize; 267 268 max_mapnr = num_physpages = max_low_pfn; 269 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 270 271 /* clear the zero-page */ 272 memset(empty_zero_page, 0, PAGE_SIZE); 273 274 /* this will put all low memory onto the freelists */ 275 totalram_pages += free_all_bootmem(); 276 277 reservedpages = 0; 278 279 codesize = (unsigned long) &_etext - (unsigned long) &_text; 280 datasize = (unsigned long) &_edata - (unsigned long) &_etext; 281 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; 282 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n", 283 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), 284 max_mapnr << (PAGE_SHIFT-10), 285 codesize >> 10, 286 reservedpages << (PAGE_SHIFT-10), 287 datasize >>10, 288 initsize >> 10); 289 printk("Write protected kernel read-only data: %#lx - %#lx\n", 290 (unsigned long)&__start_rodata, 291 PFN_ALIGN((unsigned long)&__end_rodata) - 1); 292 } 293 294 void free_initmem(void) 295 { 296 unsigned long addr; 297 298 addr = (unsigned long)(&__init_begin); 299 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) { 300 ClearPageReserved(virt_to_page(addr)); 301 init_page_count(virt_to_page(addr)); 302 free_page(addr); 303 totalram_pages++; 304 } 305 printk ("Freeing unused kernel memory: %ldk freed\n", 306 ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10); 307 } 308 309 #ifdef CONFIG_BLK_DEV_INITRD 310 void free_initrd_mem(unsigned long start, unsigned long end) 311 { 312 if (start < end) 313 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); 314 for (; start < end; start += PAGE_SIZE) { 315 ClearPageReserved(virt_to_page(start)); 316 init_page_count(virt_to_page(start)); 317 free_page(start); 318 totalram_pages++; 319 } 320 } 321 #endif 322