1 /* 2 * PowerPC version 3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 4 * 5 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) 6 * and Cort Dougan (PReP) (cort@cs.nmt.edu) 7 * Copyright (C) 1996 Paul Mackerras 8 * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). 9 * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com) 10 * 11 * Derived from "arch/i386/mm/init.c" 12 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License 16 * as published by the Free Software Foundation; either version 17 * 2 of the License, or (at your option) any later version. 18 * 19 */ 20 21 #include <linux/config.h> 22 #include <linux/module.h> 23 #include <linux/sched.h> 24 #include <linux/kernel.h> 25 #include <linux/errno.h> 26 #include <linux/string.h> 27 #include <linux/types.h> 28 #include <linux/mm.h> 29 #include <linux/stddef.h> 30 #include <linux/init.h> 31 #include <linux/bootmem.h> 32 #include <linux/highmem.h> 33 #include <linux/initrd.h> 34 #include <linux/pagemap.h> 35 36 #include <asm/pgalloc.h> 37 #include <asm/prom.h> 38 #include <asm/io.h> 39 #include <asm/mmu_context.h> 40 #include <asm/pgtable.h> 41 #include <asm/mmu.h> 42 #include <asm/smp.h> 43 #include <asm/machdep.h> 44 #include <asm/btext.h> 45 #include <asm/tlb.h> 46 #include <asm/prom.h> 47 #include <asm/lmb.h> 48 #include <asm/sections.h> 49 #include <asm/vdso.h> 50 51 #include "mmu_decl.h" 52 53 #ifndef CPU_FTR_COHERENT_ICACHE 54 #define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */ 55 #define CPU_FTR_NOEXECUTE 0 56 #endif 57 58 int init_bootmem_done; 59 int mem_init_done; 60 unsigned long memory_limit; 61 62 extern void hash_preload(struct mm_struct *mm, unsigned long ea, 63 unsigned long access, unsigned long trap); 64 65 /* 66 * This is called by /dev/mem to know if a given address has to 67 * be mapped non-cacheable or not 68 */ 69 int page_is_ram(unsigned long pfn) 70 { 71 unsigned long paddr = (pfn << PAGE_SHIFT); 72 73 #ifndef CONFIG_PPC64 /* XXX for now */ 74 return paddr < __pa(high_memory); 75 #else 76 int i; 77 for (i=0; i < lmb.memory.cnt; i++) { 78 unsigned long base; 79 80 base = lmb.memory.region[i].base; 81 82 if ((paddr >= base) && 83 (paddr < (base + lmb.memory.region[i].size))) { 84 return 1; 85 } 86 } 87 88 return 0; 89 #endif 90 } 91 EXPORT_SYMBOL(page_is_ram); 92 93 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 94 unsigned long size, pgprot_t vma_prot) 95 { 96 if (ppc_md.phys_mem_access_prot) 97 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 98 99 if (!page_is_ram(pfn)) 100 vma_prot = __pgprot(pgprot_val(vma_prot) 101 | _PAGE_GUARDED | _PAGE_NO_CACHE); 102 return vma_prot; 103 } 104 EXPORT_SYMBOL(phys_mem_access_prot); 105 106 #ifdef CONFIG_MEMORY_HOTPLUG 107 108 void online_page(struct page *page) 109 { 110 ClearPageReserved(page); 111 init_page_count(page); 112 __free_page(page); 113 totalram_pages++; 114 num_physpages++; 115 } 116 117 #ifdef CONFIG_NUMA 118 int memory_add_physaddr_to_nid(u64 start) 119 { 120 return hot_add_scn_to_nid(start); 121 } 122 #endif 123 124 int __devinit arch_add_memory(int nid, u64 start, u64 size) 125 { 126 struct pglist_data *pgdata; 127 struct zone *zone; 128 unsigned long start_pfn = start >> PAGE_SHIFT; 129 unsigned long nr_pages = size >> PAGE_SHIFT; 130 131 pgdata = NODE_DATA(nid); 132 133 start = (unsigned long)__va(start); 134 create_section_mapping(start, start + size); 135 136 /* this should work for most non-highmem platforms */ 137 zone = pgdata->node_zones; 138 139 return __add_pages(zone, start_pfn, nr_pages); 140 141 return 0; 142 } 143 144 /* 145 * First pass at this code will check to determine if the remove 146 * request is within the RMO. Do not allow removal within the RMO. 147 */ 148 int __devinit remove_memory(u64 start, u64 size) 149 { 150 struct zone *zone; 151 unsigned long start_pfn, end_pfn, nr_pages; 152 153 start_pfn = start >> PAGE_SHIFT; 154 nr_pages = size >> PAGE_SHIFT; 155 end_pfn = start_pfn + nr_pages; 156 157 printk("%s(): Attempting to remove memoy in range " 158 "%lx to %lx\n", __func__, start, start+size); 159 /* 160 * check for range within RMO 161 */ 162 zone = page_zone(pfn_to_page(start_pfn)); 163 164 printk("%s(): memory will be removed from " 165 "the %s zone\n", __func__, zone->name); 166 167 /* 168 * not handling removing memory ranges that 169 * overlap multiple zones yet 170 */ 171 if (end_pfn > (zone->zone_start_pfn + zone->spanned_pages)) 172 goto overlap; 173 174 /* make sure it is NOT in RMO */ 175 if ((start < lmb.rmo_size) || ((start+size) < lmb.rmo_size)) { 176 printk("%s(): range to be removed must NOT be in RMO!\n", 177 __func__); 178 goto in_rmo; 179 } 180 181 return __remove_pages(zone, start_pfn, nr_pages); 182 183 overlap: 184 printk("%s(): memory range to be removed overlaps " 185 "multiple zones!!!\n", __func__); 186 in_rmo: 187 return -1; 188 } 189 #endif /* CONFIG_MEMORY_HOTPLUG */ 190 191 void show_mem(void) 192 { 193 unsigned long total = 0, reserved = 0; 194 unsigned long shared = 0, cached = 0; 195 unsigned long highmem = 0; 196 struct page *page; 197 pg_data_t *pgdat; 198 unsigned long i; 199 200 printk("Mem-info:\n"); 201 show_free_areas(); 202 printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); 203 for_each_online_pgdat(pgdat) { 204 unsigned long flags; 205 pgdat_resize_lock(pgdat, &flags); 206 for (i = 0; i < pgdat->node_spanned_pages; i++) { 207 if (!pfn_valid(pgdat->node_start_pfn + i)) 208 continue; 209 page = pgdat_page_nr(pgdat, i); 210 total++; 211 if (PageHighMem(page)) 212 highmem++; 213 if (PageReserved(page)) 214 reserved++; 215 else if (PageSwapCache(page)) 216 cached++; 217 else if (page_count(page)) 218 shared += page_count(page) - 1; 219 } 220 pgdat_resize_unlock(pgdat, &flags); 221 } 222 printk("%ld pages of RAM\n", total); 223 #ifdef CONFIG_HIGHMEM 224 printk("%ld pages of HIGHMEM\n", highmem); 225 #endif 226 printk("%ld reserved pages\n", reserved); 227 printk("%ld pages shared\n", shared); 228 printk("%ld pages swap cached\n", cached); 229 } 230 231 /* 232 * Initialize the bootmem system and give it all the memory we 233 * have available. If we are using highmem, we only put the 234 * lowmem into the bootmem system. 235 */ 236 #ifndef CONFIG_NEED_MULTIPLE_NODES 237 void __init do_init_bootmem(void) 238 { 239 unsigned long i; 240 unsigned long start, bootmap_pages; 241 unsigned long total_pages; 242 int boot_mapsize; 243 244 max_pfn = total_pages = lmb_end_of_DRAM() >> PAGE_SHIFT; 245 #ifdef CONFIG_HIGHMEM 246 total_pages = total_lowmem >> PAGE_SHIFT; 247 #endif 248 249 /* 250 * Find an area to use for the bootmem bitmap. Calculate the size of 251 * bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE. 252 * Add 1 additional page in case the address isn't page-aligned. 253 */ 254 bootmap_pages = bootmem_bootmap_pages(total_pages); 255 256 start = lmb_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE); 257 258 boot_mapsize = init_bootmem(start >> PAGE_SHIFT, total_pages); 259 260 /* Add all physical memory to the bootmem map, mark each area 261 * present. 262 */ 263 for (i = 0; i < lmb.memory.cnt; i++) { 264 unsigned long base = lmb.memory.region[i].base; 265 unsigned long size = lmb_size_bytes(&lmb.memory, i); 266 #ifdef CONFIG_HIGHMEM 267 if (base >= total_lowmem) 268 continue; 269 if (base + size > total_lowmem) 270 size = total_lowmem - base; 271 #endif 272 free_bootmem(base, size); 273 } 274 275 /* reserve the sections we're already using */ 276 for (i = 0; i < lmb.reserved.cnt; i++) 277 reserve_bootmem(lmb.reserved.region[i].base, 278 lmb_size_bytes(&lmb.reserved, i)); 279 280 /* XXX need to clip this if using highmem? */ 281 for (i = 0; i < lmb.memory.cnt; i++) 282 memory_present(0, lmb_start_pfn(&lmb.memory, i), 283 lmb_end_pfn(&lmb.memory, i)); 284 init_bootmem_done = 1; 285 } 286 287 /* 288 * paging_init() sets up the page tables - in fact we've already done this. 289 */ 290 void __init paging_init(void) 291 { 292 unsigned long zones_size[MAX_NR_ZONES]; 293 unsigned long zholes_size[MAX_NR_ZONES]; 294 unsigned long total_ram = lmb_phys_mem_size(); 295 unsigned long top_of_ram = lmb_end_of_DRAM(); 296 297 #ifdef CONFIG_HIGHMEM 298 map_page(PKMAP_BASE, 0, 0); /* XXX gross */ 299 pkmap_page_table = pte_offset_kernel(pmd_offset(pgd_offset_k 300 (PKMAP_BASE), PKMAP_BASE), PKMAP_BASE); 301 map_page(KMAP_FIX_BEGIN, 0, 0); /* XXX gross */ 302 kmap_pte = pte_offset_kernel(pmd_offset(pgd_offset_k 303 (KMAP_FIX_BEGIN), KMAP_FIX_BEGIN), KMAP_FIX_BEGIN); 304 kmap_prot = PAGE_KERNEL; 305 #endif /* CONFIG_HIGHMEM */ 306 307 printk(KERN_DEBUG "Top of RAM: 0x%lx, Total RAM: 0x%lx\n", 308 top_of_ram, total_ram); 309 printk(KERN_DEBUG "Memory hole size: %ldMB\n", 310 (top_of_ram - total_ram) >> 20); 311 /* 312 * All pages are DMA-able so we put them all in the DMA zone. 313 */ 314 memset(zones_size, 0, sizeof(zones_size)); 315 memset(zholes_size, 0, sizeof(zholes_size)); 316 317 zones_size[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; 318 zholes_size[ZONE_DMA] = (top_of_ram - total_ram) >> PAGE_SHIFT; 319 320 #ifdef CONFIG_HIGHMEM 321 zones_size[ZONE_DMA] = total_lowmem >> PAGE_SHIFT; 322 zones_size[ZONE_HIGHMEM] = (total_memory - total_lowmem) >> PAGE_SHIFT; 323 zholes_size[ZONE_HIGHMEM] = (top_of_ram - total_ram) >> PAGE_SHIFT; 324 #else 325 zones_size[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; 326 zholes_size[ZONE_DMA] = (top_of_ram - total_ram) >> PAGE_SHIFT; 327 #endif /* CONFIG_HIGHMEM */ 328 329 free_area_init_node(0, NODE_DATA(0), zones_size, 330 __pa(PAGE_OFFSET) >> PAGE_SHIFT, zholes_size); 331 } 332 #endif /* ! CONFIG_NEED_MULTIPLE_NODES */ 333 334 void __init mem_init(void) 335 { 336 #ifdef CONFIG_NEED_MULTIPLE_NODES 337 int nid; 338 #endif 339 pg_data_t *pgdat; 340 unsigned long i; 341 struct page *page; 342 unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize; 343 344 num_physpages = lmb.memory.size >> PAGE_SHIFT; 345 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 346 347 #ifdef CONFIG_NEED_MULTIPLE_NODES 348 for_each_online_node(nid) { 349 if (NODE_DATA(nid)->node_spanned_pages != 0) { 350 printk("freeing bootmem node %d\n", nid); 351 totalram_pages += 352 free_all_bootmem_node(NODE_DATA(nid)); 353 } 354 } 355 #else 356 max_mapnr = max_pfn; 357 totalram_pages += free_all_bootmem(); 358 #endif 359 for_each_online_pgdat(pgdat) { 360 for (i = 0; i < pgdat->node_spanned_pages; i++) { 361 if (!pfn_valid(pgdat->node_start_pfn + i)) 362 continue; 363 page = pgdat_page_nr(pgdat, i); 364 if (PageReserved(page)) 365 reservedpages++; 366 } 367 } 368 369 codesize = (unsigned long)&_sdata - (unsigned long)&_stext; 370 datasize = (unsigned long)&_edata - (unsigned long)&_sdata; 371 initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin; 372 bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start; 373 374 #ifdef CONFIG_HIGHMEM 375 { 376 unsigned long pfn, highmem_mapnr; 377 378 highmem_mapnr = total_lowmem >> PAGE_SHIFT; 379 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 380 struct page *page = pfn_to_page(pfn); 381 382 ClearPageReserved(page); 383 init_page_count(page); 384 __free_page(page); 385 totalhigh_pages++; 386 } 387 totalram_pages += totalhigh_pages; 388 printk(KERN_DEBUG "High memory: %luk\n", 389 totalhigh_pages << (PAGE_SHIFT-10)); 390 } 391 #endif /* CONFIG_HIGHMEM */ 392 393 printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, " 394 "%luk reserved, %luk data, %luk bss, %luk init)\n", 395 (unsigned long)nr_free_pages() << (PAGE_SHIFT-10), 396 num_physpages << (PAGE_SHIFT-10), 397 codesize >> 10, 398 reservedpages << (PAGE_SHIFT-10), 399 datasize >> 10, 400 bsssize >> 10, 401 initsize >> 10); 402 403 mem_init_done = 1; 404 405 /* Initialize the vDSO */ 406 vdso_init(); 407 } 408 409 /* 410 * This is called when a page has been modified by the kernel. 411 * It just marks the page as not i-cache clean. We do the i-cache 412 * flush later when the page is given to a user process, if necessary. 413 */ 414 void flush_dcache_page(struct page *page) 415 { 416 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) 417 return; 418 /* avoid an atomic op if possible */ 419 if (test_bit(PG_arch_1, &page->flags)) 420 clear_bit(PG_arch_1, &page->flags); 421 } 422 EXPORT_SYMBOL(flush_dcache_page); 423 424 void flush_dcache_icache_page(struct page *page) 425 { 426 #ifdef CONFIG_BOOKE 427 void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE); 428 __flush_dcache_icache(start); 429 kunmap_atomic(start, KM_PPC_SYNC_ICACHE); 430 #elif defined(CONFIG_8xx) || defined(CONFIG_PPC64) 431 /* On 8xx there is no need to kmap since highmem is not supported */ 432 __flush_dcache_icache(page_address(page)); 433 #else 434 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT); 435 #endif 436 437 } 438 void clear_user_page(void *page, unsigned long vaddr, struct page *pg) 439 { 440 clear_page(page); 441 442 /* 443 * We shouldnt have to do this, but some versions of glibc 444 * require it (ld.so assumes zero filled pages are icache clean) 445 * - Anton 446 */ 447 flush_dcache_page(pg); 448 } 449 EXPORT_SYMBOL(clear_user_page); 450 451 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, 452 struct page *pg) 453 { 454 copy_page(vto, vfrom); 455 456 /* 457 * We should be able to use the following optimisation, however 458 * there are two problems. 459 * Firstly a bug in some versions of binutils meant PLT sections 460 * were not marked executable. 461 * Secondly the first word in the GOT section is blrl, used 462 * to establish the GOT address. Until recently the GOT was 463 * not marked executable. 464 * - Anton 465 */ 466 #if 0 467 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0)) 468 return; 469 #endif 470 471 flush_dcache_page(pg); 472 } 473 474 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page, 475 unsigned long addr, int len) 476 { 477 unsigned long maddr; 478 479 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK); 480 flush_icache_range(maddr, maddr + len); 481 kunmap(page); 482 } 483 EXPORT_SYMBOL(flush_icache_user_range); 484 485 /* 486 * This is called at the end of handling a user page fault, when the 487 * fault has been handled by updating a PTE in the linux page tables. 488 * We use it to preload an HPTE into the hash table corresponding to 489 * the updated linux PTE. 490 * 491 * This must always be called with the pte lock held. 492 */ 493 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 494 pte_t pte) 495 { 496 #ifdef CONFIG_PPC_STD_MMU 497 unsigned long access = 0, trap; 498 #endif 499 unsigned long pfn = pte_pfn(pte); 500 501 /* handle i-cache coherency */ 502 if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE) && 503 !cpu_has_feature(CPU_FTR_NOEXECUTE) && 504 pfn_valid(pfn)) { 505 struct page *page = pfn_to_page(pfn); 506 if (!PageReserved(page) 507 && !test_bit(PG_arch_1, &page->flags)) { 508 if (vma->vm_mm == current->active_mm) { 509 #ifdef CONFIG_8xx 510 /* On 8xx, cache control instructions (particularly 511 * "dcbst" from flush_dcache_icache) fault as write 512 * operation if there is an unpopulated TLB entry 513 * for the address in question. To workaround that, 514 * we invalidate the TLB here, thus avoiding dcbst 515 * misbehaviour. 516 */ 517 _tlbie(address); 518 #endif 519 __flush_dcache_icache((void *) address); 520 } else 521 flush_dcache_icache_page(page); 522 set_bit(PG_arch_1, &page->flags); 523 } 524 } 525 526 #ifdef CONFIG_PPC_STD_MMU 527 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ 528 if (!pte_young(pte) || address >= TASK_SIZE) 529 return; 530 531 /* We try to figure out if we are coming from an instruction 532 * access fault and pass that down to __hash_page so we avoid 533 * double-faulting on execution of fresh text. We have to test 534 * for regs NULL since init will get here first thing at boot 535 * 536 * We also avoid filling the hash if not coming from a fault 537 */ 538 if (current->thread.regs == NULL) 539 return; 540 trap = TRAP(current->thread.regs); 541 if (trap == 0x400) 542 access |= _PAGE_EXEC; 543 else if (trap != 0x300) 544 return; 545 hash_preload(vma->vm_mm, address, access, trap); 546 #endif /* CONFIG_PPC_STD_MMU */ 547 } 548