1 /* 2 * Initialize MMU support. 3 * 4 * Copyright (C) 1998-2003 Hewlett-Packard Co 5 * David Mosberger-Tang <davidm@hpl.hp.com> 6 */ 7 #include <linux/kernel.h> 8 #include <linux/init.h> 9 10 #include <linux/bootmem.h> 11 #include <linux/efi.h> 12 #include <linux/elf.h> 13 #include <linux/memblock.h> 14 #include <linux/mm.h> 15 #include <linux/mmzone.h> 16 #include <linux/module.h> 17 #include <linux/personality.h> 18 #include <linux/reboot.h> 19 #include <linux/slab.h> 20 #include <linux/swap.h> 21 #include <linux/proc_fs.h> 22 #include <linux/bitops.h> 23 #include <linux/kexec.h> 24 25 #include <asm/dma.h> 26 #include <asm/io.h> 27 #include <asm/machvec.h> 28 #include <asm/numa.h> 29 #include <asm/patch.h> 30 #include <asm/pgalloc.h> 31 #include <asm/sal.h> 32 #include <asm/sections.h> 33 #include <asm/tlb.h> 34 #include <linux/uaccess.h> 35 #include <asm/unistd.h> 36 #include <asm/mca.h> 37 38 extern void ia64_tlb_init (void); 39 40 unsigned long MAX_DMA_ADDRESS = PAGE_OFFSET + 0x100000000UL; 41 42 #ifdef CONFIG_VIRTUAL_MEM_MAP 43 unsigned long VMALLOC_END = VMALLOC_END_INIT; 44 EXPORT_SYMBOL(VMALLOC_END); 45 struct page *vmem_map; 46 EXPORT_SYMBOL(vmem_map); 47 #endif 48 49 struct page *zero_page_memmap_ptr; /* map entry for zero page */ 50 EXPORT_SYMBOL(zero_page_memmap_ptr); 51 52 void 53 __ia64_sync_icache_dcache (pte_t pte) 54 { 55 unsigned long addr; 56 struct page *page; 57 58 page = pte_page(pte); 59 addr = (unsigned long) page_address(page); 60 61 if (test_bit(PG_arch_1, &page->flags)) 62 return; /* i-cache is already coherent with d-cache */ 63 64 flush_icache_range(addr, addr + (PAGE_SIZE << compound_order(page))); 65 set_bit(PG_arch_1, &page->flags); /* mark page as clean */ 66 } 67 68 /* 69 * Since DMA is i-cache coherent, any (complete) pages that were written via 70 * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to 71 * flush them when they get mapped into an executable vm-area. 72 */ 73 void 74 dma_mark_clean(void *addr, size_t size) 75 { 76 unsigned long pg_addr, end; 77 78 pg_addr = PAGE_ALIGN((unsigned long) addr); 79 end = (unsigned long) addr + size; 80 while (pg_addr + PAGE_SIZE <= end) { 81 struct page *page = virt_to_page(pg_addr); 82 set_bit(PG_arch_1, &page->flags); 83 pg_addr += PAGE_SIZE; 84 } 85 } 86 87 inline void 88 ia64_set_rbs_bot (void) 89 { 90 unsigned long stack_size = rlimit_max(RLIMIT_STACK) & -16; 91 92 if (stack_size > MAX_USER_STACK_SIZE) 93 stack_size = MAX_USER_STACK_SIZE; 94 current->thread.rbs_bot = PAGE_ALIGN(current->mm->start_stack - stack_size); 95 } 96 97 /* 98 * This performs some platform-dependent address space initialization. 99 * On IA-64, we want to setup the VM area for the register backing 100 * store (which grows upwards) and install the gateway page which is 101 * used for signal trampolines, etc. 102 */ 103 void 104 ia64_init_addr_space (void) 105 { 106 struct vm_area_struct *vma; 107 108 ia64_set_rbs_bot(); 109 110 /* 111 * If we're out of memory and kmem_cache_alloc() returns NULL, we simply ignore 112 * the problem. When the process attempts to write to the register backing store 113 * for the first time, it will get a SEGFAULT in this case. 114 */ 115 vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL); 116 if (vma) { 117 INIT_LIST_HEAD(&vma->anon_vma_chain); 118 vma->vm_mm = current->mm; 119 vma->vm_start = current->thread.rbs_bot & PAGE_MASK; 120 vma->vm_end = vma->vm_start + PAGE_SIZE; 121 vma->vm_flags = VM_DATA_DEFAULT_FLAGS|VM_GROWSUP|VM_ACCOUNT; 122 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); 123 down_write(¤t->mm->mmap_sem); 124 if (insert_vm_struct(current->mm, vma)) { 125 up_write(¤t->mm->mmap_sem); 126 kmem_cache_free(vm_area_cachep, vma); 127 return; 128 } 129 up_write(¤t->mm->mmap_sem); 130 } 131 132 /* map NaT-page at address zero to speed up speculative dereferencing of NULL: */ 133 if (!(current->personality & MMAP_PAGE_ZERO)) { 134 vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL); 135 if (vma) { 136 INIT_LIST_HEAD(&vma->anon_vma_chain); 137 vma->vm_mm = current->mm; 138 vma->vm_end = PAGE_SIZE; 139 vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT); 140 vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO | 141 VM_DONTEXPAND | VM_DONTDUMP; 142 down_write(¤t->mm->mmap_sem); 143 if (insert_vm_struct(current->mm, vma)) { 144 up_write(¤t->mm->mmap_sem); 145 kmem_cache_free(vm_area_cachep, vma); 146 return; 147 } 148 up_write(¤t->mm->mmap_sem); 149 } 150 } 151 } 152 153 void 154 free_initmem (void) 155 { 156 free_reserved_area(ia64_imva(__init_begin), ia64_imva(__init_end), 157 -1, "unused kernel"); 158 } 159 160 void __init 161 free_initrd_mem (unsigned long start, unsigned long end) 162 { 163 /* 164 * EFI uses 4KB pages while the kernel can use 4KB or bigger. 165 * Thus EFI and the kernel may have different page sizes. It is 166 * therefore possible to have the initrd share the same page as 167 * the end of the kernel (given current setup). 168 * 169 * To avoid freeing/using the wrong page (kernel sized) we: 170 * - align up the beginning of initrd 171 * - align down the end of initrd 172 * 173 * | | 174 * |=============| a000 175 * | | 176 * | | 177 * | | 9000 178 * |/////////////| 179 * |/////////////| 180 * |=============| 8000 181 * |///INITRD////| 182 * |/////////////| 183 * |/////////////| 7000 184 * | | 185 * |KKKKKKKKKKKKK| 186 * |=============| 6000 187 * |KKKKKKKKKKKKK| 188 * |KKKKKKKKKKKKK| 189 * K=kernel using 8KB pages 190 * 191 * In this example, we must free page 8000 ONLY. So we must align up 192 * initrd_start and keep initrd_end as is. 193 */ 194 start = PAGE_ALIGN(start); 195 end = end & PAGE_MASK; 196 197 if (start < end) 198 printk(KERN_INFO "Freeing initrd memory: %ldkB freed\n", (end - start) >> 10); 199 200 for (; start < end; start += PAGE_SIZE) { 201 if (!virt_addr_valid(start)) 202 continue; 203 free_reserved_page(virt_to_page(start)); 204 } 205 } 206 207 /* 208 * This installs a clean page in the kernel's page table. 209 */ 210 static struct page * __init 211 put_kernel_page (struct page *page, unsigned long address, pgprot_t pgprot) 212 { 213 pgd_t *pgd; 214 pud_t *pud; 215 pmd_t *pmd; 216 pte_t *pte; 217 218 pgd = pgd_offset_k(address); /* note: this is NOT pgd_offset()! */ 219 220 { 221 pud = pud_alloc(&init_mm, pgd, address); 222 if (!pud) 223 goto out; 224 pmd = pmd_alloc(&init_mm, pud, address); 225 if (!pmd) 226 goto out; 227 pte = pte_alloc_kernel(pmd, address); 228 if (!pte) 229 goto out; 230 if (!pte_none(*pte)) 231 goto out; 232 set_pte(pte, mk_pte(page, pgprot)); 233 } 234 out: 235 /* no need for flush_tlb */ 236 return page; 237 } 238 239 static void __init 240 setup_gate (void) 241 { 242 struct page *page; 243 244 /* 245 * Map the gate page twice: once read-only to export the ELF 246 * headers etc. and once execute-only page to enable 247 * privilege-promotion via "epc": 248 */ 249 page = virt_to_page(ia64_imva(__start_gate_section)); 250 put_kernel_page(page, GATE_ADDR, PAGE_READONLY); 251 #ifdef HAVE_BUGGY_SEGREL 252 page = virt_to_page(ia64_imva(__start_gate_section + PAGE_SIZE)); 253 put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE); 254 #else 255 put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE); 256 /* Fill in the holes (if any) with read-only zero pages: */ 257 { 258 unsigned long addr; 259 260 for (addr = GATE_ADDR + PAGE_SIZE; 261 addr < GATE_ADDR + PERCPU_PAGE_SIZE; 262 addr += PAGE_SIZE) 263 { 264 put_kernel_page(ZERO_PAGE(0), addr, 265 PAGE_READONLY); 266 put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE, 267 PAGE_READONLY); 268 } 269 } 270 #endif 271 ia64_patch_gate(); 272 } 273 274 static struct vm_area_struct gate_vma; 275 276 static int __init gate_vma_init(void) 277 { 278 gate_vma.vm_mm = NULL; 279 gate_vma.vm_start = FIXADDR_USER_START; 280 gate_vma.vm_end = FIXADDR_USER_END; 281 gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC; 282 gate_vma.vm_page_prot = __P101; 283 284 return 0; 285 } 286 __initcall(gate_vma_init); 287 288 struct vm_area_struct *get_gate_vma(struct mm_struct *mm) 289 { 290 return &gate_vma; 291 } 292 293 int in_gate_area_no_mm(unsigned long addr) 294 { 295 if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END)) 296 return 1; 297 return 0; 298 } 299 300 int in_gate_area(struct mm_struct *mm, unsigned long addr) 301 { 302 return in_gate_area_no_mm(addr); 303 } 304 305 void ia64_mmu_init(void *my_cpu_data) 306 { 307 unsigned long pta, impl_va_bits; 308 extern void tlb_init(void); 309 310 #ifdef CONFIG_DISABLE_VHPT 311 # define VHPT_ENABLE_BIT 0 312 #else 313 # define VHPT_ENABLE_BIT 1 314 #endif 315 316 /* 317 * Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped 318 * address space. The IA-64 architecture guarantees that at least 50 bits of 319 * virtual address space are implemented but if we pick a large enough page size 320 * (e.g., 64KB), the mapped address space is big enough that it will overlap with 321 * VMLPT. I assume that once we run on machines big enough to warrant 64KB pages, 322 * IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a 323 * problem in practice. Alternatively, we could truncate the top of the mapped 324 * address space to not permit mappings that would overlap with the VMLPT. 325 * --davidm 00/12/06 326 */ 327 # define pte_bits 3 328 # define mapped_space_bits (3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT) 329 /* 330 * The virtual page table has to cover the entire implemented address space within 331 * a region even though not all of this space may be mappable. The reason for 332 * this is that the Access bit and Dirty bit fault handlers perform 333 * non-speculative accesses to the virtual page table, so the address range of the 334 * virtual page table itself needs to be covered by virtual page table. 335 */ 336 # define vmlpt_bits (impl_va_bits - PAGE_SHIFT + pte_bits) 337 # define POW2(n) (1ULL << (n)) 338 339 impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61))); 340 341 if (impl_va_bits < 51 || impl_va_bits > 61) 342 panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1); 343 /* 344 * mapped_space_bits - PAGE_SHIFT is the total number of ptes we need, 345 * which must fit into "vmlpt_bits - pte_bits" slots. Second half of 346 * the test makes sure that our mapped space doesn't overlap the 347 * unimplemented hole in the middle of the region. 348 */ 349 if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) || 350 (mapped_space_bits > impl_va_bits - 1)) 351 panic("Cannot build a big enough virtual-linear page table" 352 " to cover mapped address space.\n" 353 " Try using a smaller page size.\n"); 354 355 356 /* place the VMLPT at the end of each page-table mapped region: */ 357 pta = POW2(61) - POW2(vmlpt_bits); 358 359 /* 360 * Set the (virtually mapped linear) page table address. Bit 361 * 8 selects between the short and long format, bits 2-7 the 362 * size of the table, and bit 0 whether the VHPT walker is 363 * enabled. 364 */ 365 ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT); 366 367 ia64_tlb_init(); 368 369 #ifdef CONFIG_HUGETLB_PAGE 370 ia64_set_rr(HPAGE_REGION_BASE, HPAGE_SHIFT << 2); 371 ia64_srlz_d(); 372 #endif 373 } 374 375 #ifdef CONFIG_VIRTUAL_MEM_MAP 376 int vmemmap_find_next_valid_pfn(int node, int i) 377 { 378 unsigned long end_address, hole_next_pfn; 379 unsigned long stop_address; 380 pg_data_t *pgdat = NODE_DATA(node); 381 382 end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i]; 383 end_address = PAGE_ALIGN(end_address); 384 stop_address = (unsigned long) &vmem_map[pgdat_end_pfn(pgdat)]; 385 386 do { 387 pgd_t *pgd; 388 pud_t *pud; 389 pmd_t *pmd; 390 pte_t *pte; 391 392 pgd = pgd_offset_k(end_address); 393 if (pgd_none(*pgd)) { 394 end_address += PGDIR_SIZE; 395 continue; 396 } 397 398 pud = pud_offset(pgd, end_address); 399 if (pud_none(*pud)) { 400 end_address += PUD_SIZE; 401 continue; 402 } 403 404 pmd = pmd_offset(pud, end_address); 405 if (pmd_none(*pmd)) { 406 end_address += PMD_SIZE; 407 continue; 408 } 409 410 pte = pte_offset_kernel(pmd, end_address); 411 retry_pte: 412 if (pte_none(*pte)) { 413 end_address += PAGE_SIZE; 414 pte++; 415 if ((end_address < stop_address) && 416 (end_address != ALIGN(end_address, 1UL << PMD_SHIFT))) 417 goto retry_pte; 418 continue; 419 } 420 /* Found next valid vmem_map page */ 421 break; 422 } while (end_address < stop_address); 423 424 end_address = min(end_address, stop_address); 425 end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1; 426 hole_next_pfn = end_address / sizeof(struct page); 427 return hole_next_pfn - pgdat->node_start_pfn; 428 } 429 430 int __init create_mem_map_page_table(u64 start, u64 end, void *arg) 431 { 432 unsigned long address, start_page, end_page; 433 struct page *map_start, *map_end; 434 int node; 435 pgd_t *pgd; 436 pud_t *pud; 437 pmd_t *pmd; 438 pte_t *pte; 439 440 map_start = vmem_map + (__pa(start) >> PAGE_SHIFT); 441 map_end = vmem_map + (__pa(end) >> PAGE_SHIFT); 442 443 start_page = (unsigned long) map_start & PAGE_MASK; 444 end_page = PAGE_ALIGN((unsigned long) map_end); 445 node = paddr_to_nid(__pa(start)); 446 447 for (address = start_page; address < end_page; address += PAGE_SIZE) { 448 pgd = pgd_offset_k(address); 449 if (pgd_none(*pgd)) 450 pgd_populate(&init_mm, pgd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)); 451 pud = pud_offset(pgd, address); 452 453 if (pud_none(*pud)) 454 pud_populate(&init_mm, pud, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)); 455 pmd = pmd_offset(pud, address); 456 457 if (pmd_none(*pmd)) 458 pmd_populate_kernel(&init_mm, pmd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)); 459 pte = pte_offset_kernel(pmd, address); 460 461 if (pte_none(*pte)) 462 set_pte(pte, pfn_pte(__pa(alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)) >> PAGE_SHIFT, 463 PAGE_KERNEL)); 464 } 465 return 0; 466 } 467 468 struct memmap_init_callback_data { 469 struct page *start; 470 struct page *end; 471 int nid; 472 unsigned long zone; 473 }; 474 475 static int __meminit 476 virtual_memmap_init(u64 start, u64 end, void *arg) 477 { 478 struct memmap_init_callback_data *args; 479 struct page *map_start, *map_end; 480 481 args = (struct memmap_init_callback_data *) arg; 482 map_start = vmem_map + (__pa(start) >> PAGE_SHIFT); 483 map_end = vmem_map + (__pa(end) >> PAGE_SHIFT); 484 485 if (map_start < args->start) 486 map_start = args->start; 487 if (map_end > args->end) 488 map_end = args->end; 489 490 /* 491 * We have to initialize "out of bounds" struct page elements that fit completely 492 * on the same pages that were allocated for the "in bounds" elements because they 493 * may be referenced later (and found to be "reserved"). 494 */ 495 map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1)) / sizeof(struct page); 496 map_end += ((PAGE_ALIGN((unsigned long) map_end) - (unsigned long) map_end) 497 / sizeof(struct page)); 498 499 if (map_start < map_end) 500 memmap_init_zone((unsigned long)(map_end - map_start), 501 args->nid, args->zone, page_to_pfn(map_start), 502 MEMMAP_EARLY); 503 return 0; 504 } 505 506 void __meminit 507 memmap_init (unsigned long size, int nid, unsigned long zone, 508 unsigned long start_pfn) 509 { 510 if (!vmem_map) 511 memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY); 512 else { 513 struct page *start; 514 struct memmap_init_callback_data args; 515 516 start = pfn_to_page(start_pfn); 517 args.start = start; 518 args.end = start + size; 519 args.nid = nid; 520 args.zone = zone; 521 522 efi_memmap_walk(virtual_memmap_init, &args); 523 } 524 } 525 526 int 527 ia64_pfn_valid (unsigned long pfn) 528 { 529 char byte; 530 struct page *pg = pfn_to_page(pfn); 531 532 return (__get_user(byte, (char __user *) pg) == 0) 533 && ((((u64)pg & PAGE_MASK) == (((u64)(pg + 1) - 1) & PAGE_MASK)) 534 || (__get_user(byte, (char __user *) (pg + 1) - 1) == 0)); 535 } 536 EXPORT_SYMBOL(ia64_pfn_valid); 537 538 int __init find_largest_hole(u64 start, u64 end, void *arg) 539 { 540 u64 *max_gap = arg; 541 542 static u64 last_end = PAGE_OFFSET; 543 544 /* NOTE: this algorithm assumes efi memmap table is ordered */ 545 546 if (*max_gap < (start - last_end)) 547 *max_gap = start - last_end; 548 last_end = end; 549 return 0; 550 } 551 552 #endif /* CONFIG_VIRTUAL_MEM_MAP */ 553 554 int __init register_active_ranges(u64 start, u64 len, int nid) 555 { 556 u64 end = start + len; 557 558 #ifdef CONFIG_KEXEC 559 if (start > crashk_res.start && start < crashk_res.end) 560 start = crashk_res.end; 561 if (end > crashk_res.start && end < crashk_res.end) 562 end = crashk_res.start; 563 #endif 564 565 if (start < end) 566 memblock_add_node(__pa(start), end - start, nid); 567 return 0; 568 } 569 570 int 571 find_max_min_low_pfn (u64 start, u64 end, void *arg) 572 { 573 unsigned long pfn_start, pfn_end; 574 #ifdef CONFIG_FLATMEM 575 pfn_start = (PAGE_ALIGN(__pa(start))) >> PAGE_SHIFT; 576 pfn_end = (PAGE_ALIGN(__pa(end - 1))) >> PAGE_SHIFT; 577 #else 578 pfn_start = GRANULEROUNDDOWN(__pa(start)) >> PAGE_SHIFT; 579 pfn_end = GRANULEROUNDUP(__pa(end - 1)) >> PAGE_SHIFT; 580 #endif 581 min_low_pfn = min(min_low_pfn, pfn_start); 582 max_low_pfn = max(max_low_pfn, pfn_end); 583 return 0; 584 } 585 586 /* 587 * Boot command-line option "nolwsys" can be used to disable the use of any light-weight 588 * system call handler. When this option is in effect, all fsyscalls will end up bubbling 589 * down into the kernel and calling the normal (heavy-weight) syscall handler. This is 590 * useful for performance testing, but conceivably could also come in handy for debugging 591 * purposes. 592 */ 593 594 static int nolwsys __initdata; 595 596 static int __init 597 nolwsys_setup (char *s) 598 { 599 nolwsys = 1; 600 return 1; 601 } 602 603 __setup("nolwsys", nolwsys_setup); 604 605 void __init 606 mem_init (void) 607 { 608 int i; 609 610 BUG_ON(PTRS_PER_PGD * sizeof(pgd_t) != PAGE_SIZE); 611 BUG_ON(PTRS_PER_PMD * sizeof(pmd_t) != PAGE_SIZE); 612 BUG_ON(PTRS_PER_PTE * sizeof(pte_t) != PAGE_SIZE); 613 614 #ifdef CONFIG_PCI 615 /* 616 * This needs to be called _after_ the command line has been parsed but _before_ 617 * any drivers that may need the PCI DMA interface are initialized or bootmem has 618 * been freed. 619 */ 620 platform_dma_init(); 621 #endif 622 623 #ifdef CONFIG_FLATMEM 624 BUG_ON(!mem_map); 625 #endif 626 627 set_max_mapnr(max_low_pfn); 628 high_memory = __va(max_low_pfn * PAGE_SIZE); 629 free_all_bootmem(); 630 mem_init_print_info(NULL); 631 632 /* 633 * For fsyscall entrpoints with no light-weight handler, use the ordinary 634 * (heavy-weight) handler, but mark it by setting bit 0, so the fsyscall entry 635 * code can tell them apart. 636 */ 637 for (i = 0; i < NR_syscalls; ++i) { 638 extern unsigned long fsyscall_table[NR_syscalls]; 639 extern unsigned long sys_call_table[NR_syscalls]; 640 641 if (!fsyscall_table[i] || nolwsys) 642 fsyscall_table[i] = sys_call_table[i] | 1; 643 } 644 setup_gate(); 645 } 646 647 #ifdef CONFIG_MEMORY_HOTPLUG 648 int arch_add_memory(int nid, u64 start, u64 size, bool for_device) 649 { 650 pg_data_t *pgdat; 651 struct zone *zone; 652 unsigned long start_pfn = start >> PAGE_SHIFT; 653 unsigned long nr_pages = size >> PAGE_SHIFT; 654 int ret; 655 656 pgdat = NODE_DATA(nid); 657 658 zone = pgdat->node_zones + 659 zone_for_memory(nid, start, size, ZONE_NORMAL, for_device); 660 ret = __add_pages(nid, zone, start_pfn, nr_pages); 661 662 if (ret) 663 printk("%s: Problem encountered in __add_pages() as ret=%d\n", 664 __func__, ret); 665 666 return ret; 667 } 668 669 #ifdef CONFIG_MEMORY_HOTREMOVE 670 int arch_remove_memory(u64 start, u64 size) 671 { 672 unsigned long start_pfn = start >> PAGE_SHIFT; 673 unsigned long nr_pages = size >> PAGE_SHIFT; 674 struct zone *zone; 675 int ret; 676 677 zone = page_zone(pfn_to_page(start_pfn)); 678 ret = __remove_pages(zone, start_pfn, nr_pages); 679 if (ret) 680 pr_warn("%s: Problem encountered in __remove_pages() as" 681 " ret=%d\n", __func__, ret); 682 683 return ret; 684 } 685 #endif 686 #endif 687 688 /** 689 * show_mem - give short summary of memory stats 690 * 691 * Shows a simple page count of reserved and used pages in the system. 692 * For discontig machines, it does this on a per-pgdat basis. 693 */ 694 void show_mem(unsigned int filter) 695 { 696 int total_reserved = 0; 697 unsigned long total_present = 0; 698 pg_data_t *pgdat; 699 700 printk(KERN_INFO "Mem-info:\n"); 701 show_free_areas(filter); 702 printk(KERN_INFO "Node memory in pages:\n"); 703 for_each_online_pgdat(pgdat) { 704 unsigned long present; 705 unsigned long flags; 706 int reserved = 0; 707 int nid = pgdat->node_id; 708 int zoneid; 709 710 if (skip_free_areas_node(filter, nid)) 711 continue; 712 pgdat_resize_lock(pgdat, &flags); 713 714 for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) { 715 struct zone *zone = &pgdat->node_zones[zoneid]; 716 if (!populated_zone(zone)) 717 continue; 718 719 reserved += zone->present_pages - zone->managed_pages; 720 } 721 present = pgdat->node_present_pages; 722 723 pgdat_resize_unlock(pgdat, &flags); 724 total_present += present; 725 total_reserved += reserved; 726 printk(KERN_INFO "Node %4d: RAM: %11ld, rsvd: %8d, ", 727 nid, present, reserved); 728 } 729 printk(KERN_INFO "%ld pages of RAM\n", total_present); 730 printk(KERN_INFO "%d reserved pages\n", total_reserved); 731 printk(KERN_INFO "Total of %ld pages in page table cache\n", 732 quicklist_total_size()); 733 printk(KERN_INFO "%ld free buffer pages\n", nr_free_buffer_pages()); 734 } 735