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