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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 | /* * arch/s390/mm/init.c * * S390 version * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation * Author(s): Hartmut Penner (hp@de.ibm.com) * * Derived from "arch/i386/mm/init.c" * Copyright (C) 1995 Linus Torvalds */ #include <linux/config.h> #include <linux/signal.h> #include <linux/sched.h> #include <linux/kernel.h> #include <linux/errno.h> #include <linux/string.h> #include <linux/types.h> #include <linux/ptrace.h> #include <linux/mman.h> #include <linux/mm.h> #include <linux/swap.h> #include <linux/smp.h> #include <linux/init.h> #include <asm/system.h> #include <asm/uaccess.h> #include <asm/pgtable.h> #include <asm/dma.h> #include <asm/lowcore.h> static int test_access(unsigned long loc) { static const int ssm_mask = 0x07000000L; int rc, i; rc = 0; for (i=0; i<4; i++) { __asm__ __volatile__( " slr %0,%0\n" " ssm %1\n" " tprot 0(%2),0\n" "0: jne 1f\n" " lhi %0,1\n" "1: ssm %3\n" ".section __ex_table,\"a\"\n" " .align 4\n" " .long 0b,1b\n" ".previous" : "+&d" (rc) : "i" (0), "a" (loc), "m" (ssm_mask) : "cc"); if (rc == 0) break; loc += 0x100000; } return rc; } extern void show_net_buffers(void); extern unsigned long initrd_start,initrd_end; static inline void invalidate_page(pte_t *pte) { int i; for (i=0;i<PTRS_PER_PTE;i++) pte_clear(pte++); } void __bad_pte_kernel(pmd_t *pmd) { printk("Bad pmd in pte_alloc: %08lx\n", pmd_val(*pmd)); pmd_val(*pmd) = _KERNPG_TABLE + __pa(BAD_PAGETABLE); } void __bad_pte(pmd_t *pmd) { printk("Bad pmd in pte_alloc: %08lx\n", pmd_val(*pmd)); pmd_val(*pmd) = _PAGE_TABLE + __pa(BAD_PAGETABLE); } pte_t *get_pte_kernel_slow(pmd_t *pmd, unsigned long offset) { pte_t *pte; pte = (pte_t *) __get_free_page(GFP_KERNEL); if (pmd_none(*pmd)) { if (pte) { invalidate_page(pte); pmd_val(pmd[0]) = _KERNPG_TABLE + __pa(pte); pmd_val(pmd[1]) = _KERNPG_TABLE + __pa(pte)+1024; pmd_val(pmd[2]) = _KERNPG_TABLE + __pa(pte)+2048; pmd_val(pmd[3]) = _KERNPG_TABLE + __pa(pte)+3072; return pte + offset; } pmd_val(pmd[0]) = _KERNPG_TABLE + __pa(BAD_PAGETABLE); pmd_val(pmd[1]) = _KERNPG_TABLE + __pa(BAD_PAGETABLE)+1024; pmd_val(pmd[2]) = _KERNPG_TABLE + __pa(BAD_PAGETABLE)+2048; pmd_val(pmd[3]) = _KERNPG_TABLE + __pa(BAD_PAGETABLE)+3072; return NULL; } free_page((unsigned long)pte); if (pmd_bad(*pmd)) { __bad_pte_kernel(pmd); return NULL; } return (pte_t *) pmd_page(*pmd) + offset; } pte_t *get_pte_slow(pmd_t *pmd, unsigned long offset) { unsigned long pte; pte = (unsigned long) __get_free_page(GFP_KERNEL); if (pmd_none(*pmd)) { if (pte) { invalidate_page((pte_t*) pte); pmd_val(pmd[0]) = _PAGE_TABLE + __pa(pte); pmd_val(pmd[1]) = _PAGE_TABLE + __pa(pte)+1024; pmd_val(pmd[2]) = _PAGE_TABLE + __pa(pte)+2048; pmd_val(pmd[3]) = _PAGE_TABLE + __pa(pte)+3072; return (pte_t *) pte + offset; } pmd_val(pmd[0]) = _PAGE_TABLE + __pa(BAD_PAGETABLE); pmd_val(pmd[1]) = _PAGE_TABLE + __pa(BAD_PAGETABLE)+1024; pmd_val(pmd[2]) = _PAGE_TABLE + __pa(BAD_PAGETABLE)+2048; pmd_val(pmd[3]) = _PAGE_TABLE + __pa(BAD_PAGETABLE)+3072; return NULL; } free_page(pte); if (pmd_bad(*pmd)) { __bad_pte(pmd); return NULL; } return (pte_t *) pmd_page(*pmd) + offset; } int do_check_pgt_cache(int low, int high) { int freed = 0; if(pgtable_cache_size > high) { do { if(pgd_quicklist) free_pgd_slow(get_pgd_fast()), freed += 2; if(pmd_quicklist) free_pmd_slow(get_pmd_fast()), freed++; if(pte_quicklist) free_pte_slow(get_pte_fast()), freed++; } while(pgtable_cache_size > low); } return freed; } /* * BAD_PAGE is the page that is used for page faults when linux * is out-of-memory. Older versions of linux just did a * do_exit(), but using this instead means there is less risk * for a process dying in kernel mode, possibly leaving an inode * unused etc.. * * BAD_PAGETABLE is the accompanying page-table: it is initialized * to point to BAD_PAGE entries. * * ZERO_PAGE is a special page that is used for zero-initialized * data and COW. */ pte_t * __bad_pagetable(void) { extern char empty_bad_page_table[PAGE_SIZE]; memset((void *)empty_bad_page_table, 0, PAGE_SIZE); return (pte_t *) empty_bad_page_table; } pte_t __bad_page(void) { extern char empty_bad_page[PAGE_SIZE]; memset((void *)empty_bad_page, 0, PAGE_SIZE); return pte_mkdirty(mk_pte((unsigned long) empty_bad_page, PAGE_SHARED)); } void show_mem(void) { int i,free = 0,total = 0,reserved = 0; int shared = 0, cached = 0; printk("Mem-info:\n"); show_free_areas(); printk("Free swap: %6dkB\n",nr_swap_pages<<(PAGE_SHIFT-10)); i = max_mapnr; while (i-- > 0) { total++; if (PageReserved(mem_map+i)) reserved++; else if (PageSwapCache(mem_map+i)) cached++; else if (!atomic_read(&mem_map[i].count)) free++; else shared += atomic_read(&mem_map[i].count) - 1; } printk("%d pages of RAM\n",total); printk("%d reserved pages\n",reserved); printk("%d pages shared\n",shared); printk("%d pages swap cached\n",cached); printk("%ld pages in page table cache\n",pgtable_cache_size); show_buffers(); #ifdef CONFIG_NET show_net_buffers(); #endif } extern unsigned long free_area_init(unsigned long, unsigned long); /* References to section boundaries */ extern unsigned long _text; extern unsigned long _etext; extern unsigned long _edata; extern unsigned long __bss_start; extern unsigned long _end; extern unsigned long __init_begin; extern unsigned long __init_end; /* * the initial mapping is set up by linload to address of 4 MB * to enable virtual addressing to the first 4 MB * paging_init will erase this initial mapping */ pgd_t swapper_pg_dir[512] __attribute__ ((__aligned__ (4096))); unsigned long empty_bad_page[1024] __attribute__ ((__aligned__ (4096))); unsigned long empty_zero_page[1024] __attribute__ ((__aligned__ (4096))); pte_t empty_bad_page_table[1024] __attribute__ ((__aligned__ (4096))); /* * paging_init() sets up the page tables - note that the first 4MB are * already mapped by head.S. * * This routines also unmaps the page at virtual kernel address 0, so * that we can trap those pesky NULL-reference errors in the kernel. */ __initfunc(unsigned long paging_init(unsigned long start_mem, unsigned long end_mem)) { pgd_t * pg_dir; pte_t * pg_table; pte_t pte; int i; unsigned long tmp; unsigned long address=0; unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE; static const int ssm_mask = 0x04000000L; /* unmap whole virtual address space */ pg_dir = swapper_pg_dir; for (i=0;i<KERNEL_PGD_PTRS;i++) pmd_clear((pmd_t*)pg_dir++); /* * map whole physical memory to virtual memory (identity mapping) */ start_mem = PAGE_ALIGN(start_mem); pg_dir = swapper_pg_dir; while (address < end_mem) { /* * pg_table is physical at this point */ pg_table = (pte_t *) __pa(start_mem); pg_dir->pgd0 = (_PAGE_TABLE | ((unsigned long) pg_table)); pg_dir->pgd1 = (_PAGE_TABLE | ((unsigned long) pg_table+1024)); pg_dir->pgd2 = (_PAGE_TABLE | ((unsigned long) pg_table+2048)); pg_dir->pgd3 = (_PAGE_TABLE | ((unsigned long) pg_table+3072)); pg_dir++; /* now change pg_table to kernel virtual addresses */ pg_table = (pte_t *) start_mem; start_mem += PAGE_SIZE; for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) { pte = mk_pte(address, PAGE_KERNEL); if (address >= end_mem) pte_clear(&pte); set_pte(pg_table, pte); address += PAGE_SIZE; } } /* enable virtual mapping in kernel mode */ __asm__ __volatile__(" LCTL 1,1,%0\n" " LCTL 7,7,%0\n" " LCTL 13,13,%0\n" " SSM %1" : : "m" (pgdir_k), "m" (ssm_mask)); local_flush_tlb(); return free_area_init(start_mem, end_mem); } __initfunc(void mem_init(unsigned long start_mem, unsigned long end_mem)) { unsigned long start_low_mem = PAGE_SIZE; int codepages = 0; int reservedpages = 0; int datapages = 0; int initpages = 0; unsigned long tmp; end_mem &= PAGE_MASK; high_memory = (void *) end_mem; max_mapnr = num_physpages = MAP_NR(end_mem); /* clear the zero-page */ memset(empty_zero_page, 0, PAGE_SIZE); /* mark usable pages in the mem_map[] */ start_low_mem = PAGE_ALIGN(start_low_mem)+PAGE_OFFSET; #if 0 /* FIXME: WHATS THAT FOR ?!?! */ #ifdef __SMP__ /* * But first pinch a few for the stack/trampoline stuff * FIXME: Don't need the extra page at 4K, but need to fix * trampoline before removing it. (see the GDT stuff) * */ start_low_mem += PAGE_SIZE; /* 32bit startup code*/ start_low_mem = smp_alloc_memory(start_low_mem);/* AP processor stacks*/ #endif #endif start_mem = PAGE_ALIGN(start_mem); tmp = start_mem; while (tmp < end_mem) { if (tmp && (tmp & 0x3ff000) == 0 && test_access(tmp) == 0) { int i; printk("4M Segment %lX not available\n",tmp); for (i = 0;i<0x400;i++) { set_bit(PG_reserved, &mem_map[MAP_NR(tmp)].flags); tmp += PAGE_SIZE; } } else { clear_bit(PG_reserved, &mem_map[MAP_NR(tmp)].flags); tmp += PAGE_SIZE; } } for (tmp = PAGE_OFFSET ; tmp < end_mem ; tmp += PAGE_SIZE) { if (PageReserved(mem_map+MAP_NR(tmp))) { if (tmp >= (unsigned long) &_text && tmp < (unsigned long) &_edata) { if (tmp < (unsigned long) &_etext) { #if 0 if (tmp >= 0x00001000UL) { pgd_t *pgd = pgd_offset_k(tmp); pmd_t *pmd = pmd_offset(pgd, tmp); pte_t *pte = pte_offset(pmd, tmp); *pte = pte_wrprotect(*pte); } #endif codepages++; } else datapages++; } else if (tmp >= (unsigned long) __init_begin && tmp < (unsigned long) __init_end) initpages++; else if (tmp >= (unsigned long) &__bss_start && tmp < (unsigned long) start_mem) datapages++; else reservedpages++; continue; } atomic_set(&mem_map[MAP_NR(tmp)].count, 1); #ifdef CONFIG_BLK_DEV_INITRD if (!initrd_start || (tmp < initrd_start || tmp >= initrd_end)) #endif free_page(tmp); } printk("Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init)\n", (unsigned long) nr_free_pages << (PAGE_SHIFT-10), max_mapnr << (PAGE_SHIFT-10), codepages << (PAGE_SHIFT-10), reservedpages << (PAGE_SHIFT-10), datapages << (PAGE_SHIFT-10), initpages << (PAGE_SHIFT-10)); } void free_initmem(void) { unsigned long addr; addr = (unsigned long)(&__init_begin); for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) { mem_map[MAP_NR(addr)].flags &= ~(1 << PG_reserved); atomic_set(&mem_map[MAP_NR(addr)].count, 1); free_page(addr); } printk ("Freeing unused kernel memory: %dk freed\n", (&__init_end - &__init_begin) >> 10); } void si_meminfo(struct sysinfo *val) { int i; i = max_mapnr; val->totalram = 0; val->sharedram = 0; val->freeram = nr_free_pages << PAGE_SHIFT; val->bufferram = buffermem; while (i-- > 0) { if (PageReserved(mem_map+i)) continue; val->totalram++; if (!atomic_read(&mem_map[i].count)) continue; val->sharedram += atomic_read(&mem_map[i].count) - 1; } val->totalram <<= PAGE_SHIFT; val->sharedram <<= PAGE_SHIFT; return; } |