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 set_page_count(page, 0); 112 free_cold_page(page); 113 totalram_pages++; 114 num_physpages++; 115 } 116 117 /* 118 * This works only for the non-NUMA case. Later, we'll need a lookup 119 * to convert from real physical addresses to nid, that doesn't use 120 * pfn_to_nid(). 121 */ 122 int __devinit add_memory(u64 start, u64 size) 123 { 124 struct pglist_data *pgdata = NODE_DATA(0); 125 struct zone *zone; 126 unsigned long start_pfn = start >> PAGE_SHIFT; 127 unsigned long nr_pages = size >> PAGE_SHIFT; 128 129 start += KERNELBASE; 130 create_section_mapping(start, start + size); 131 132 /* this should work for most non-highmem platforms */ 133 zone = pgdata->node_zones; 134 135 return __add_pages(zone, start_pfn, nr_pages); 136 137 return 0; 138 } 139 140 /* 141 * First pass at this code will check to determine if the remove 142 * request is within the RMO. Do not allow removal within the RMO. 143 */ 144 int __devinit remove_memory(u64 start, u64 size) 145 { 146 struct zone *zone; 147 unsigned long start_pfn, end_pfn, nr_pages; 148 149 start_pfn = start >> PAGE_SHIFT; 150 nr_pages = size >> PAGE_SHIFT; 151 end_pfn = start_pfn + nr_pages; 152 153 printk("%s(): Attempting to remove memoy in range " 154 "%lx to %lx\n", __func__, start, start+size); 155 /* 156 * check for range within RMO 157 */ 158 zone = page_zone(pfn_to_page(start_pfn)); 159 160 printk("%s(): memory will be removed from " 161 "the %s zone\n", __func__, zone->name); 162 163 /* 164 * not handling removing memory ranges that 165 * overlap multiple zones yet 166 */ 167 if (end_pfn > (zone->zone_start_pfn + zone->spanned_pages)) 168 goto overlap; 169 170 /* make sure it is NOT in RMO */ 171 if ((start < lmb.rmo_size) || ((start+size) < lmb.rmo_size)) { 172 printk("%s(): range to be removed must NOT be in RMO!\n", 173 __func__); 174 goto in_rmo; 175 } 176 177 return __remove_pages(zone, start_pfn, nr_pages); 178 179 overlap: 180 printk("%s(): memory range to be removed overlaps " 181 "multiple zones!!!\n", __func__); 182 in_rmo: 183 return -1; 184 } 185 #endif /* CONFIG_MEMORY_HOTPLUG */ 186 187 void show_mem(void) 188 { 189 unsigned long total = 0, reserved = 0; 190 unsigned long shared = 0, cached = 0; 191 unsigned long highmem = 0; 192 struct page *page; 193 pg_data_t *pgdat; 194 unsigned long i; 195 196 printk("Mem-info:\n"); 197 show_free_areas(); 198 printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); 199 for_each_pgdat(pgdat) { 200 unsigned long flags; 201 pgdat_resize_lock(pgdat, &flags); 202 for (i = 0; i < pgdat->node_spanned_pages; i++) { 203 if (!pfn_valid(pgdat->node_start_pfn + i)) 204 continue; 205 page = pgdat_page_nr(pgdat, i); 206 total++; 207 if (PageHighMem(page)) 208 highmem++; 209 if (PageReserved(page)) 210 reserved++; 211 else if (PageSwapCache(page)) 212 cached++; 213 else if (page_count(page)) 214 shared += page_count(page) - 1; 215 } 216 pgdat_resize_unlock(pgdat, &flags); 217 } 218 printk("%ld pages of RAM\n", total); 219 #ifdef CONFIG_HIGHMEM 220 printk("%ld pages of HIGHMEM\n", highmem); 221 #endif 222 printk("%ld reserved pages\n", reserved); 223 printk("%ld pages shared\n", shared); 224 printk("%ld pages swap cached\n", cached); 225 } 226 227 /* 228 * Initialize the bootmem system and give it all the memory we 229 * have available. If we are using highmem, we only put the 230 * lowmem into the bootmem system. 231 */ 232 #ifndef CONFIG_NEED_MULTIPLE_NODES 233 void __init do_init_bootmem(void) 234 { 235 unsigned long i; 236 unsigned long start, bootmap_pages; 237 unsigned long total_pages; 238 int boot_mapsize; 239 240 max_pfn = total_pages = lmb_end_of_DRAM() >> PAGE_SHIFT; 241 #ifdef CONFIG_HIGHMEM 242 total_pages = total_lowmem >> PAGE_SHIFT; 243 #endif 244 245 /* 246 * Find an area to use for the bootmem bitmap. Calculate the size of 247 * bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE. 248 * Add 1 additional page in case the address isn't page-aligned. 249 */ 250 bootmap_pages = bootmem_bootmap_pages(total_pages); 251 252 start = lmb_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE); 253 BUG_ON(!start); 254 255 boot_mapsize = init_bootmem(start >> PAGE_SHIFT, total_pages); 256 257 /* Add all physical memory to the bootmem map, mark each area 258 * present. 259 */ 260 for (i = 0; i < lmb.memory.cnt; i++) { 261 unsigned long base = lmb.memory.region[i].base; 262 unsigned long size = lmb_size_bytes(&lmb.memory, i); 263 #ifdef CONFIG_HIGHMEM 264 if (base >= total_lowmem) 265 continue; 266 if (base + size > total_lowmem) 267 size = total_lowmem - base; 268 #endif 269 free_bootmem(base, size); 270 } 271 272 /* reserve the sections we're already using */ 273 for (i = 0; i < lmb.reserved.cnt; i++) 274 reserve_bootmem(lmb.reserved.region[i].base, 275 lmb_size_bytes(&lmb.reserved, i)); 276 277 /* XXX need to clip this if using highmem? */ 278 for (i = 0; i < lmb.memory.cnt; i++) 279 memory_present(0, lmb_start_pfn(&lmb.memory, i), 280 lmb_end_pfn(&lmb.memory, i)); 281 init_bootmem_done = 1; 282 } 283 284 /* 285 * paging_init() sets up the page tables - in fact we've already done this. 286 */ 287 void __init paging_init(void) 288 { 289 unsigned long zones_size[MAX_NR_ZONES]; 290 unsigned long zholes_size[MAX_NR_ZONES]; 291 unsigned long total_ram = lmb_phys_mem_size(); 292 unsigned long top_of_ram = lmb_end_of_DRAM(); 293 294 #ifdef CONFIG_HIGHMEM 295 map_page(PKMAP_BASE, 0, 0); /* XXX gross */ 296 pkmap_page_table = pte_offset_kernel(pmd_offset(pgd_offset_k 297 (PKMAP_BASE), PKMAP_BASE), PKMAP_BASE); 298 map_page(KMAP_FIX_BEGIN, 0, 0); /* XXX gross */ 299 kmap_pte = pte_offset_kernel(pmd_offset(pgd_offset_k 300 (KMAP_FIX_BEGIN), KMAP_FIX_BEGIN), KMAP_FIX_BEGIN); 301 kmap_prot = PAGE_KERNEL; 302 #endif /* CONFIG_HIGHMEM */ 303 304 printk(KERN_INFO "Top of RAM: 0x%lx, Total RAM: 0x%lx\n", 305 top_of_ram, total_ram); 306 printk(KERN_INFO "Memory hole size: %ldMB\n", 307 (top_of_ram - total_ram) >> 20); 308 /* 309 * All pages are DMA-able so we put them all in the DMA zone. 310 */ 311 memset(zones_size, 0, sizeof(zones_size)); 312 memset(zholes_size, 0, sizeof(zholes_size)); 313 314 zones_size[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; 315 zholes_size[ZONE_DMA] = (top_of_ram - total_ram) >> PAGE_SHIFT; 316 317 #ifdef CONFIG_HIGHMEM 318 zones_size[ZONE_DMA] = total_lowmem >> PAGE_SHIFT; 319 zones_size[ZONE_HIGHMEM] = (total_memory - total_lowmem) >> PAGE_SHIFT; 320 zholes_size[ZONE_HIGHMEM] = (top_of_ram - total_ram) >> PAGE_SHIFT; 321 #else 322 zones_size[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; 323 zholes_size[ZONE_DMA] = (top_of_ram - total_ram) >> PAGE_SHIFT; 324 #endif /* CONFIG_HIGHMEM */ 325 326 free_area_init_node(0, NODE_DATA(0), zones_size, 327 __pa(PAGE_OFFSET) >> PAGE_SHIFT, zholes_size); 328 } 329 #endif /* ! CONFIG_NEED_MULTIPLE_NODES */ 330 331 void __init mem_init(void) 332 { 333 #ifdef CONFIG_NEED_MULTIPLE_NODES 334 int nid; 335 #endif 336 pg_data_t *pgdat; 337 unsigned long i; 338 struct page *page; 339 unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize; 340 341 num_physpages = lmb.memory.size >> PAGE_SHIFT; 342 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 343 344 #ifdef CONFIG_NEED_MULTIPLE_NODES 345 for_each_online_node(nid) { 346 if (NODE_DATA(nid)->node_spanned_pages != 0) { 347 printk("freeing bootmem node %x\n", nid); 348 totalram_pages += 349 free_all_bootmem_node(NODE_DATA(nid)); 350 } 351 } 352 #else 353 max_mapnr = max_pfn; 354 totalram_pages += free_all_bootmem(); 355 #endif 356 for_each_pgdat(pgdat) { 357 for (i = 0; i < pgdat->node_spanned_pages; i++) { 358 if (!pfn_valid(pgdat->node_start_pfn + i)) 359 continue; 360 page = pgdat_page_nr(pgdat, i); 361 if (PageReserved(page)) 362 reservedpages++; 363 } 364 } 365 366 codesize = (unsigned long)&_sdata - (unsigned long)&_stext; 367 datasize = (unsigned long)&_edata - (unsigned long)&_sdata; 368 initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin; 369 bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start; 370 371 #ifdef CONFIG_HIGHMEM 372 { 373 unsigned long pfn, highmem_mapnr; 374 375 highmem_mapnr = total_lowmem >> PAGE_SHIFT; 376 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 377 struct page *page = pfn_to_page(pfn); 378 379 ClearPageReserved(page); 380 set_page_count(page, 1); 381 __free_page(page); 382 totalhigh_pages++; 383 } 384 totalram_pages += totalhigh_pages; 385 printk(KERN_INFO "High memory: %luk\n", 386 totalhigh_pages << (PAGE_SHIFT-10)); 387 } 388 #endif /* CONFIG_HIGHMEM */ 389 390 printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, " 391 "%luk reserved, %luk data, %luk bss, %luk init)\n", 392 (unsigned long)nr_free_pages() << (PAGE_SHIFT-10), 393 num_physpages << (PAGE_SHIFT-10), 394 codesize >> 10, 395 reservedpages << (PAGE_SHIFT-10), 396 datasize >> 10, 397 bsssize >> 10, 398 initsize >> 10); 399 400 mem_init_done = 1; 401 402 /* Initialize the vDSO */ 403 vdso_init(); 404 } 405 406 /* 407 * This is called when a page has been modified by the kernel. 408 * It just marks the page as not i-cache clean. We do the i-cache 409 * flush later when the page is given to a user process, if necessary. 410 */ 411 void flush_dcache_page(struct page *page) 412 { 413 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) 414 return; 415 /* avoid an atomic op if possible */ 416 if (test_bit(PG_arch_1, &page->flags)) 417 clear_bit(PG_arch_1, &page->flags); 418 } 419 EXPORT_SYMBOL(flush_dcache_page); 420 421 void flush_dcache_icache_page(struct page *page) 422 { 423 #ifdef CONFIG_BOOKE 424 void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE); 425 __flush_dcache_icache(start); 426 kunmap_atomic(start, KM_PPC_SYNC_ICACHE); 427 #elif defined(CONFIG_8xx) || defined(CONFIG_PPC64) 428 /* On 8xx there is no need to kmap since highmem is not supported */ 429 __flush_dcache_icache(page_address(page)); 430 #else 431 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT); 432 #endif 433 434 } 435 void clear_user_page(void *page, unsigned long vaddr, struct page *pg) 436 { 437 clear_page(page); 438 439 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) 440 return; 441 /* 442 * We shouldnt have to do this, but some versions of glibc 443 * require it (ld.so assumes zero filled pages are icache clean) 444 * - Anton 445 */ 446 447 /* avoid an atomic op if possible */ 448 if (test_bit(PG_arch_1, &pg->flags)) 449 clear_bit(PG_arch_1, &pg->flags); 450 } 451 EXPORT_SYMBOL(clear_user_page); 452 453 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, 454 struct page *pg) 455 { 456 copy_page(vto, vfrom); 457 458 /* 459 * We should be able to use the following optimisation, however 460 * there are two problems. 461 * Firstly a bug in some versions of binutils meant PLT sections 462 * were not marked executable. 463 * Secondly the first word in the GOT section is blrl, used 464 * to establish the GOT address. Until recently the GOT was 465 * not marked executable. 466 * - Anton 467 */ 468 #if 0 469 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0)) 470 return; 471 #endif 472 473 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) 474 return; 475 476 /* avoid an atomic op if possible */ 477 if (test_bit(PG_arch_1, &pg->flags)) 478 clear_bit(PG_arch_1, &pg->flags); 479 } 480 481 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page, 482 unsigned long addr, int len) 483 { 484 unsigned long maddr; 485 486 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK); 487 flush_icache_range(maddr, maddr + len); 488 kunmap(page); 489 } 490 EXPORT_SYMBOL(flush_icache_user_range); 491 492 /* 493 * This is called at the end of handling a user page fault, when the 494 * fault has been handled by updating a PTE in the linux page tables. 495 * We use it to preload an HPTE into the hash table corresponding to 496 * the updated linux PTE. 497 * 498 * This must always be called with the pte lock held. 499 */ 500 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 501 pte_t pte) 502 { 503 #ifdef CONFIG_PPC_STD_MMU 504 unsigned long access = 0, trap; 505 #endif 506 unsigned long pfn = pte_pfn(pte); 507 508 /* handle i-cache coherency */ 509 if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE) && 510 !cpu_has_feature(CPU_FTR_NOEXECUTE) && 511 pfn_valid(pfn)) { 512 struct page *page = pfn_to_page(pfn); 513 if (!PageReserved(page) 514 && !test_bit(PG_arch_1, &page->flags)) { 515 if (vma->vm_mm == current->active_mm) { 516 #ifdef CONFIG_8xx 517 /* On 8xx, cache control instructions (particularly 518 * "dcbst" from flush_dcache_icache) fault as write 519 * operation if there is an unpopulated TLB entry 520 * for the address in question. To workaround that, 521 * we invalidate the TLB here, thus avoiding dcbst 522 * misbehaviour. 523 */ 524 _tlbie(address); 525 #endif 526 __flush_dcache_icache((void *) address); 527 } else 528 flush_dcache_icache_page(page); 529 set_bit(PG_arch_1, &page->flags); 530 } 531 } 532 533 #ifdef CONFIG_PPC_STD_MMU 534 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ 535 if (!pte_young(pte) || address >= TASK_SIZE) 536 return; 537 538 /* We try to figure out if we are coming from an instruction 539 * access fault and pass that down to __hash_page so we avoid 540 * double-faulting on execution of fresh text. We have to test 541 * for regs NULL since init will get here first thing at boot 542 * 543 * We also avoid filling the hash if not coming from a fault 544 */ 545 if (current->thread.regs == NULL) 546 return; 547 trap = TRAP(current->thread.regs); 548 if (trap == 0x400) 549 access |= _PAGE_EXEC; 550 else if (trap != 0x300) 551 return; 552 hash_preload(vma->vm_mm, address, access, trap); 553 #endif /* CONFIG_PPC_STD_MMU */ 554 } 555