1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Initialize MMU support. 4 * 5 * Copyright (C) 1998-2003 Hewlett-Packard Co 6 * David Mosberger-Tang <davidm@hpl.hp.com> 7 */ 8 #include <linux/kernel.h> 9 #include <linux/init.h> 10 11 #include <linux/dma-noncoherent.h> 12 #include <linux/dmar.h> 13 #include <linux/efi.h> 14 #include <linux/elf.h> 15 #include <linux/memblock.h> 16 #include <linux/mm.h> 17 #include <linux/sched/signal.h> 18 #include <linux/mmzone.h> 19 #include <linux/module.h> 20 #include <linux/personality.h> 21 #include <linux/reboot.h> 22 #include <linux/slab.h> 23 #include <linux/swap.h> 24 #include <linux/proc_fs.h> 25 #include <linux/bitops.h> 26 #include <linux/kexec.h> 27 #include <linux/swiotlb.h> 28 29 #include <asm/dma.h> 30 #include <asm/io.h> 31 #include <asm/numa.h> 32 #include <asm/patch.h> 33 #include <asm/pgalloc.h> 34 #include <asm/sal.h> 35 #include <asm/sections.h> 36 #include <asm/tlb.h> 37 #include <linux/uaccess.h> 38 #include <asm/unistd.h> 39 #include <asm/mca.h> 40 41 extern void ia64_tlb_init (void); 42 43 unsigned long MAX_DMA_ADDRESS = PAGE_OFFSET + 0x100000000UL; 44 45 #ifdef CONFIG_VIRTUAL_MEM_MAP 46 unsigned long VMALLOC_END = VMALLOC_END_INIT; 47 EXPORT_SYMBOL(VMALLOC_END); 48 struct page *vmem_map; 49 EXPORT_SYMBOL(vmem_map); 50 #endif 51 52 struct page *zero_page_memmap_ptr; /* map entry for zero page */ 53 EXPORT_SYMBOL(zero_page_memmap_ptr); 54 55 void 56 __ia64_sync_icache_dcache (pte_t pte) 57 { 58 unsigned long addr; 59 struct page *page; 60 61 page = pte_page(pte); 62 addr = (unsigned long) page_address(page); 63 64 if (test_bit(PG_arch_1, &page->flags)) 65 return; /* i-cache is already coherent with d-cache */ 66 67 flush_icache_range(addr, addr + page_size(page)); 68 set_bit(PG_arch_1, &page->flags); /* mark page as clean */ 69 } 70 71 /* 72 * Since DMA is i-cache coherent, any (complete) pages that were written via 73 * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to 74 * flush them when they get mapped into an executable vm-area. 75 */ 76 void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr, 77 size_t size, enum dma_data_direction dir) 78 { 79 unsigned long pfn = PHYS_PFN(paddr); 80 81 do { 82 set_bit(PG_arch_1, &pfn_to_page(pfn)->flags); 83 } while (++pfn <= PHYS_PFN(paddr + size - 1)); 84 } 85 86 inline void 87 ia64_set_rbs_bot (void) 88 { 89 unsigned long stack_size = rlimit_max(RLIMIT_STACK) & -16; 90 91 if (stack_size > MAX_USER_STACK_SIZE) 92 stack_size = MAX_USER_STACK_SIZE; 93 current->thread.rbs_bot = PAGE_ALIGN(current->mm->start_stack - stack_size); 94 } 95 96 /* 97 * This performs some platform-dependent address space initialization. 98 * On IA-64, we want to setup the VM area for the register backing 99 * store (which grows upwards) and install the gateway page which is 100 * used for signal trampolines, etc. 101 */ 102 void 103 ia64_init_addr_space (void) 104 { 105 struct vm_area_struct *vma; 106 107 ia64_set_rbs_bot(); 108 109 /* 110 * If we're out of memory and kmem_cache_alloc() returns NULL, we simply ignore 111 * the problem. When the process attempts to write to the register backing store 112 * for the first time, it will get a SEGFAULT in this case. 113 */ 114 vma = vm_area_alloc(current->mm); 115 if (vma) { 116 vma_set_anonymous(vma); 117 vma->vm_start = current->thread.rbs_bot & PAGE_MASK; 118 vma->vm_end = vma->vm_start + PAGE_SIZE; 119 vma->vm_flags = VM_DATA_DEFAULT_FLAGS|VM_GROWSUP|VM_ACCOUNT; 120 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); 121 down_write(¤t->mm->mmap_sem); 122 if (insert_vm_struct(current->mm, vma)) { 123 up_write(¤t->mm->mmap_sem); 124 vm_area_free(vma); 125 return; 126 } 127 up_write(¤t->mm->mmap_sem); 128 } 129 130 /* map NaT-page at address zero to speed up speculative dereferencing of NULL: */ 131 if (!(current->personality & MMAP_PAGE_ZERO)) { 132 vma = vm_area_alloc(current->mm); 133 if (vma) { 134 vma_set_anonymous(vma); 135 vma->vm_end = PAGE_SIZE; 136 vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT); 137 vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO | 138 VM_DONTEXPAND | VM_DONTDUMP; 139 down_write(¤t->mm->mmap_sem); 140 if (insert_vm_struct(current->mm, vma)) { 141 up_write(¤t->mm->mmap_sem); 142 vm_area_free(vma); 143 return; 144 } 145 up_write(¤t->mm->mmap_sem); 146 } 147 } 148 } 149 150 void 151 free_initmem (void) 152 { 153 free_reserved_area(ia64_imva(__init_begin), ia64_imva(__init_end), 154 -1, "unused kernel"); 155 } 156 157 void __init 158 free_initrd_mem (unsigned long start, unsigned long end) 159 { 160 /* 161 * EFI uses 4KB pages while the kernel can use 4KB or bigger. 162 * Thus EFI and the kernel may have different page sizes. It is 163 * therefore possible to have the initrd share the same page as 164 * the end of the kernel (given current setup). 165 * 166 * To avoid freeing/using the wrong page (kernel sized) we: 167 * - align up the beginning of initrd 168 * - align down the end of initrd 169 * 170 * | | 171 * |=============| a000 172 * | | 173 * | | 174 * | | 9000 175 * |/////////////| 176 * |/////////////| 177 * |=============| 8000 178 * |///INITRD////| 179 * |/////////////| 180 * |/////////////| 7000 181 * | | 182 * |KKKKKKKKKKKKK| 183 * |=============| 6000 184 * |KKKKKKKKKKKKK| 185 * |KKKKKKKKKKKKK| 186 * K=kernel using 8KB pages 187 * 188 * In this example, we must free page 8000 ONLY. So we must align up 189 * initrd_start and keep initrd_end as is. 190 */ 191 start = PAGE_ALIGN(start); 192 end = end & PAGE_MASK; 193 194 if (start < end) 195 printk(KERN_INFO "Freeing initrd memory: %ldkB freed\n", (end - start) >> 10); 196 197 for (; start < end; start += PAGE_SIZE) { 198 if (!virt_addr_valid(start)) 199 continue; 200 free_reserved_page(virt_to_page(start)); 201 } 202 } 203 204 /* 205 * This installs a clean page in the kernel's page table. 206 */ 207 static struct page * __init 208 put_kernel_page (struct page *page, unsigned long address, pgprot_t pgprot) 209 { 210 pgd_t *pgd; 211 pud_t *pud; 212 pmd_t *pmd; 213 pte_t *pte; 214 215 pgd = pgd_offset_k(address); /* note: this is NOT pgd_offset()! */ 216 217 { 218 pud = pud_alloc(&init_mm, pgd, address); 219 if (!pud) 220 goto out; 221 pmd = pmd_alloc(&init_mm, pud, address); 222 if (!pmd) 223 goto out; 224 pte = pte_alloc_kernel(pmd, address); 225 if (!pte) 226 goto out; 227 if (!pte_none(*pte)) 228 goto out; 229 set_pte(pte, mk_pte(page, pgprot)); 230 } 231 out: 232 /* no need for flush_tlb */ 233 return page; 234 } 235 236 static void __init 237 setup_gate (void) 238 { 239 struct page *page; 240 241 /* 242 * Map the gate page twice: once read-only to export the ELF 243 * headers etc. and once execute-only page to enable 244 * privilege-promotion via "epc": 245 */ 246 page = virt_to_page(ia64_imva(__start_gate_section)); 247 put_kernel_page(page, GATE_ADDR, PAGE_READONLY); 248 #ifdef HAVE_BUGGY_SEGREL 249 page = virt_to_page(ia64_imva(__start_gate_section + PAGE_SIZE)); 250 put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE); 251 #else 252 put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE); 253 /* Fill in the holes (if any) with read-only zero pages: */ 254 { 255 unsigned long addr; 256 257 for (addr = GATE_ADDR + PAGE_SIZE; 258 addr < GATE_ADDR + PERCPU_PAGE_SIZE; 259 addr += PAGE_SIZE) 260 { 261 put_kernel_page(ZERO_PAGE(0), addr, 262 PAGE_READONLY); 263 put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE, 264 PAGE_READONLY); 265 } 266 } 267 #endif 268 ia64_patch_gate(); 269 } 270 271 static struct vm_area_struct gate_vma; 272 273 static int __init gate_vma_init(void) 274 { 275 vma_init(&gate_vma, NULL); 276 gate_vma.vm_start = FIXADDR_USER_START; 277 gate_vma.vm_end = FIXADDR_USER_END; 278 gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC; 279 gate_vma.vm_page_prot = __P101; 280 281 return 0; 282 } 283 __initcall(gate_vma_init); 284 285 struct vm_area_struct *get_gate_vma(struct mm_struct *mm) 286 { 287 return &gate_vma; 288 } 289 290 int in_gate_area_no_mm(unsigned long addr) 291 { 292 if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END)) 293 return 1; 294 return 0; 295 } 296 297 int in_gate_area(struct mm_struct *mm, unsigned long addr) 298 { 299 return in_gate_area_no_mm(addr); 300 } 301 302 void ia64_mmu_init(void *my_cpu_data) 303 { 304 unsigned long pta, impl_va_bits; 305 extern void tlb_init(void); 306 307 #ifdef CONFIG_DISABLE_VHPT 308 # define VHPT_ENABLE_BIT 0 309 #else 310 # define VHPT_ENABLE_BIT 1 311 #endif 312 313 /* 314 * Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped 315 * address space. The IA-64 architecture guarantees that at least 50 bits of 316 * virtual address space are implemented but if we pick a large enough page size 317 * (e.g., 64KB), the mapped address space is big enough that it will overlap with 318 * VMLPT. I assume that once we run on machines big enough to warrant 64KB pages, 319 * IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a 320 * problem in practice. Alternatively, we could truncate the top of the mapped 321 * address space to not permit mappings that would overlap with the VMLPT. 322 * --davidm 00/12/06 323 */ 324 # define pte_bits 3 325 # define mapped_space_bits (3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT) 326 /* 327 * The virtual page table has to cover the entire implemented address space within 328 * a region even though not all of this space may be mappable. The reason for 329 * this is that the Access bit and Dirty bit fault handlers perform 330 * non-speculative accesses to the virtual page table, so the address range of the 331 * virtual page table itself needs to be covered by virtual page table. 332 */ 333 # define vmlpt_bits (impl_va_bits - PAGE_SHIFT + pte_bits) 334 # define POW2(n) (1ULL << (n)) 335 336 impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61))); 337 338 if (impl_va_bits < 51 || impl_va_bits > 61) 339 panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1); 340 /* 341 * mapped_space_bits - PAGE_SHIFT is the total number of ptes we need, 342 * which must fit into "vmlpt_bits - pte_bits" slots. Second half of 343 * the test makes sure that our mapped space doesn't overlap the 344 * unimplemented hole in the middle of the region. 345 */ 346 if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) || 347 (mapped_space_bits > impl_va_bits - 1)) 348 panic("Cannot build a big enough virtual-linear page table" 349 " to cover mapped address space.\n" 350 " Try using a smaller page size.\n"); 351 352 353 /* place the VMLPT at the end of each page-table mapped region: */ 354 pta = POW2(61) - POW2(vmlpt_bits); 355 356 /* 357 * Set the (virtually mapped linear) page table address. Bit 358 * 8 selects between the short and long format, bits 2-7 the 359 * size of the table, and bit 0 whether the VHPT walker is 360 * enabled. 361 */ 362 ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT); 363 364 ia64_tlb_init(); 365 366 #ifdef CONFIG_HUGETLB_PAGE 367 ia64_set_rr(HPAGE_REGION_BASE, HPAGE_SHIFT << 2); 368 ia64_srlz_d(); 369 #endif 370 } 371 372 #ifdef CONFIG_VIRTUAL_MEM_MAP 373 int vmemmap_find_next_valid_pfn(int node, int i) 374 { 375 unsigned long end_address, hole_next_pfn; 376 unsigned long stop_address; 377 pg_data_t *pgdat = NODE_DATA(node); 378 379 end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i]; 380 end_address = PAGE_ALIGN(end_address); 381 stop_address = (unsigned long) &vmem_map[pgdat_end_pfn(pgdat)]; 382 383 do { 384 pgd_t *pgd; 385 pud_t *pud; 386 pmd_t *pmd; 387 pte_t *pte; 388 389 pgd = pgd_offset_k(end_address); 390 if (pgd_none(*pgd)) { 391 end_address += PGDIR_SIZE; 392 continue; 393 } 394 395 pud = pud_offset(pgd, end_address); 396 if (pud_none(*pud)) { 397 end_address += PUD_SIZE; 398 continue; 399 } 400 401 pmd = pmd_offset(pud, end_address); 402 if (pmd_none(*pmd)) { 403 end_address += PMD_SIZE; 404 continue; 405 } 406 407 pte = pte_offset_kernel(pmd, end_address); 408 retry_pte: 409 if (pte_none(*pte)) { 410 end_address += PAGE_SIZE; 411 pte++; 412 if ((end_address < stop_address) && 413 (end_address != ALIGN(end_address, 1UL << PMD_SHIFT))) 414 goto retry_pte; 415 continue; 416 } 417 /* Found next valid vmem_map page */ 418 break; 419 } while (end_address < stop_address); 420 421 end_address = min(end_address, stop_address); 422 end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1; 423 hole_next_pfn = end_address / sizeof(struct page); 424 return hole_next_pfn - pgdat->node_start_pfn; 425 } 426 427 int __init create_mem_map_page_table(u64 start, u64 end, void *arg) 428 { 429 unsigned long address, start_page, end_page; 430 struct page *map_start, *map_end; 431 int node; 432 pgd_t *pgd; 433 pud_t *pud; 434 pmd_t *pmd; 435 pte_t *pte; 436 437 map_start = vmem_map + (__pa(start) >> PAGE_SHIFT); 438 map_end = vmem_map + (__pa(end) >> PAGE_SHIFT); 439 440 start_page = (unsigned long) map_start & PAGE_MASK; 441 end_page = PAGE_ALIGN((unsigned long) map_end); 442 node = paddr_to_nid(__pa(start)); 443 444 for (address = start_page; address < end_page; address += PAGE_SIZE) { 445 pgd = pgd_offset_k(address); 446 if (pgd_none(*pgd)) { 447 pud = memblock_alloc_node(PAGE_SIZE, PAGE_SIZE, node); 448 if (!pud) 449 goto err_alloc; 450 pgd_populate(&init_mm, pgd, pud); 451 } 452 pud = pud_offset(pgd, address); 453 454 if (pud_none(*pud)) { 455 pmd = memblock_alloc_node(PAGE_SIZE, PAGE_SIZE, node); 456 if (!pmd) 457 goto err_alloc; 458 pud_populate(&init_mm, pud, pmd); 459 } 460 pmd = pmd_offset(pud, address); 461 462 if (pmd_none(*pmd)) { 463 pte = memblock_alloc_node(PAGE_SIZE, PAGE_SIZE, node); 464 if (!pte) 465 goto err_alloc; 466 pmd_populate_kernel(&init_mm, pmd, pte); 467 } 468 pte = pte_offset_kernel(pmd, address); 469 470 if (pte_none(*pte)) { 471 void *page = memblock_alloc_node(PAGE_SIZE, PAGE_SIZE, 472 node); 473 if (!page) 474 goto err_alloc; 475 set_pte(pte, pfn_pte(__pa(page) >> PAGE_SHIFT, 476 PAGE_KERNEL)); 477 } 478 } 479 return 0; 480 481 err_alloc: 482 panic("%s: Failed to allocate %lu bytes align=0x%lx nid=%d\n", 483 __func__, PAGE_SIZE, PAGE_SIZE, node); 484 return -ENOMEM; 485 } 486 487 struct memmap_init_callback_data { 488 struct page *start; 489 struct page *end; 490 int nid; 491 unsigned long zone; 492 }; 493 494 static int __meminit 495 virtual_memmap_init(u64 start, u64 end, void *arg) 496 { 497 struct memmap_init_callback_data *args; 498 struct page *map_start, *map_end; 499 500 args = (struct memmap_init_callback_data *) arg; 501 map_start = vmem_map + (__pa(start) >> PAGE_SHIFT); 502 map_end = vmem_map + (__pa(end) >> PAGE_SHIFT); 503 504 if (map_start < args->start) 505 map_start = args->start; 506 if (map_end > args->end) 507 map_end = args->end; 508 509 /* 510 * We have to initialize "out of bounds" struct page elements that fit completely 511 * on the same pages that were allocated for the "in bounds" elements because they 512 * may be referenced later (and found to be "reserved"). 513 */ 514 map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1)) / sizeof(struct page); 515 map_end += ((PAGE_ALIGN((unsigned long) map_end) - (unsigned long) map_end) 516 / sizeof(struct page)); 517 518 if (map_start < map_end) 519 memmap_init_zone((unsigned long)(map_end - map_start), 520 args->nid, args->zone, page_to_pfn(map_start), 521 MEMMAP_EARLY, NULL); 522 return 0; 523 } 524 525 void __meminit 526 memmap_init (unsigned long size, int nid, unsigned long zone, 527 unsigned long start_pfn) 528 { 529 if (!vmem_map) { 530 memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY, 531 NULL); 532 } else { 533 struct page *start; 534 struct memmap_init_callback_data args; 535 536 start = pfn_to_page(start_pfn); 537 args.start = start; 538 args.end = start + size; 539 args.nid = nid; 540 args.zone = zone; 541 542 efi_memmap_walk(virtual_memmap_init, &args); 543 } 544 } 545 546 int 547 ia64_pfn_valid (unsigned long pfn) 548 { 549 char byte; 550 struct page *pg = pfn_to_page(pfn); 551 552 return (__get_user(byte, (char __user *) pg) == 0) 553 && ((((u64)pg & PAGE_MASK) == (((u64)(pg + 1) - 1) & PAGE_MASK)) 554 || (__get_user(byte, (char __user *) (pg + 1) - 1) == 0)); 555 } 556 EXPORT_SYMBOL(ia64_pfn_valid); 557 558 int __init find_largest_hole(u64 start, u64 end, void *arg) 559 { 560 u64 *max_gap = arg; 561 562 static u64 last_end = PAGE_OFFSET; 563 564 /* NOTE: this algorithm assumes efi memmap table is ordered */ 565 566 if (*max_gap < (start - last_end)) 567 *max_gap = start - last_end; 568 last_end = end; 569 return 0; 570 } 571 572 #endif /* CONFIG_VIRTUAL_MEM_MAP */ 573 574 int __init register_active_ranges(u64 start, u64 len, int nid) 575 { 576 u64 end = start + len; 577 578 #ifdef CONFIG_KEXEC 579 if (start > crashk_res.start && start < crashk_res.end) 580 start = crashk_res.end; 581 if (end > crashk_res.start && end < crashk_res.end) 582 end = crashk_res.start; 583 #endif 584 585 if (start < end) 586 memblock_add_node(__pa(start), end - start, nid); 587 return 0; 588 } 589 590 int 591 find_max_min_low_pfn (u64 start, u64 end, void *arg) 592 { 593 unsigned long pfn_start, pfn_end; 594 #ifdef CONFIG_FLATMEM 595 pfn_start = (PAGE_ALIGN(__pa(start))) >> PAGE_SHIFT; 596 pfn_end = (PAGE_ALIGN(__pa(end - 1))) >> PAGE_SHIFT; 597 #else 598 pfn_start = GRANULEROUNDDOWN(__pa(start)) >> PAGE_SHIFT; 599 pfn_end = GRANULEROUNDUP(__pa(end - 1)) >> PAGE_SHIFT; 600 #endif 601 min_low_pfn = min(min_low_pfn, pfn_start); 602 max_low_pfn = max(max_low_pfn, pfn_end); 603 return 0; 604 } 605 606 /* 607 * Boot command-line option "nolwsys" can be used to disable the use of any light-weight 608 * system call handler. When this option is in effect, all fsyscalls will end up bubbling 609 * down into the kernel and calling the normal (heavy-weight) syscall handler. This is 610 * useful for performance testing, but conceivably could also come in handy for debugging 611 * purposes. 612 */ 613 614 static int nolwsys __initdata; 615 616 static int __init 617 nolwsys_setup (char *s) 618 { 619 nolwsys = 1; 620 return 1; 621 } 622 623 __setup("nolwsys", nolwsys_setup); 624 625 void __init 626 mem_init (void) 627 { 628 int i; 629 630 BUG_ON(PTRS_PER_PGD * sizeof(pgd_t) != PAGE_SIZE); 631 BUG_ON(PTRS_PER_PMD * sizeof(pmd_t) != PAGE_SIZE); 632 BUG_ON(PTRS_PER_PTE * sizeof(pte_t) != PAGE_SIZE); 633 634 /* 635 * This needs to be called _after_ the command line has been parsed but 636 * _before_ any drivers that may need the PCI DMA interface are 637 * initialized or bootmem has been freed. 638 */ 639 #ifdef CONFIG_INTEL_IOMMU 640 detect_intel_iommu(); 641 if (!iommu_detected) 642 #endif 643 #ifdef CONFIG_SWIOTLB 644 swiotlb_init(1); 645 #endif 646 647 #ifdef CONFIG_FLATMEM 648 BUG_ON(!mem_map); 649 #endif 650 651 set_max_mapnr(max_low_pfn); 652 high_memory = __va(max_low_pfn * PAGE_SIZE); 653 memblock_free_all(); 654 mem_init_print_info(NULL); 655 656 /* 657 * For fsyscall entrpoints with no light-weight handler, use the ordinary 658 * (heavy-weight) handler, but mark it by setting bit 0, so the fsyscall entry 659 * code can tell them apart. 660 */ 661 for (i = 0; i < NR_syscalls; ++i) { 662 extern unsigned long fsyscall_table[NR_syscalls]; 663 extern unsigned long sys_call_table[NR_syscalls]; 664 665 if (!fsyscall_table[i] || nolwsys) 666 fsyscall_table[i] = sys_call_table[i] | 1; 667 } 668 setup_gate(); 669 } 670 671 #ifdef CONFIG_MEMORY_HOTPLUG 672 int arch_add_memory(int nid, u64 start, u64 size, 673 struct mhp_restrictions *restrictions) 674 { 675 unsigned long start_pfn = start >> PAGE_SHIFT; 676 unsigned long nr_pages = size >> PAGE_SHIFT; 677 int ret; 678 679 ret = __add_pages(nid, start_pfn, nr_pages, restrictions); 680 if (ret) 681 printk("%s: Problem encountered in __add_pages() as ret=%d\n", 682 __func__, ret); 683 684 return ret; 685 } 686 687 void arch_remove_memory(int nid, u64 start, u64 size, 688 struct vmem_altmap *altmap) 689 { 690 unsigned long start_pfn = start >> PAGE_SHIFT; 691 unsigned long nr_pages = size >> PAGE_SHIFT; 692 struct zone *zone; 693 694 zone = page_zone(pfn_to_page(start_pfn)); 695 __remove_pages(zone, start_pfn, nr_pages, altmap); 696 } 697 #endif 698