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(phys_addr_t paddr, size_t size, 77 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 mmap_write_lock(current->mm); 122 if (insert_vm_struct(current->mm, vma)) { 123 mmap_write_unlock(current->mm); 124 vm_area_free(vma); 125 return; 126 } 127 mmap_write_unlock(current->mm); 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 mmap_write_lock(current->mm); 140 if (insert_vm_struct(current->mm, vma)) { 141 mmap_write_unlock(current->mm); 142 vm_area_free(vma); 143 return; 144 } 145 mmap_write_unlock(current->mm); 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 p4d_t *p4d; 212 pud_t *pud; 213 pmd_t *pmd; 214 pte_t *pte; 215 216 pgd = pgd_offset_k(address); /* note: this is NOT pgd_offset()! */ 217 218 { 219 p4d = p4d_alloc(&init_mm, pgd, address); 220 if (!p4d) 221 goto out; 222 pud = pud_alloc(&init_mm, p4d, address); 223 if (!pud) 224 goto out; 225 pmd = pmd_alloc(&init_mm, pud, address); 226 if (!pmd) 227 goto out; 228 pte = pte_alloc_kernel(pmd, address); 229 if (!pte) 230 goto out; 231 if (!pte_none(*pte)) 232 goto out; 233 set_pte(pte, mk_pte(page, pgprot)); 234 } 235 out: 236 /* no need for flush_tlb */ 237 return page; 238 } 239 240 static void __init 241 setup_gate (void) 242 { 243 struct page *page; 244 245 /* 246 * Map the gate page twice: once read-only to export the ELF 247 * headers etc. and once execute-only page to enable 248 * privilege-promotion via "epc": 249 */ 250 page = virt_to_page(ia64_imva(__start_gate_section)); 251 put_kernel_page(page, GATE_ADDR, PAGE_READONLY); 252 #ifdef HAVE_BUGGY_SEGREL 253 page = virt_to_page(ia64_imva(__start_gate_section + PAGE_SIZE)); 254 put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE); 255 #else 256 put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE); 257 /* Fill in the holes (if any) with read-only zero pages: */ 258 { 259 unsigned long addr; 260 261 for (addr = GATE_ADDR + PAGE_SIZE; 262 addr < GATE_ADDR + PERCPU_PAGE_SIZE; 263 addr += PAGE_SIZE) 264 { 265 put_kernel_page(ZERO_PAGE(0), addr, 266 PAGE_READONLY); 267 put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE, 268 PAGE_READONLY); 269 } 270 } 271 #endif 272 ia64_patch_gate(); 273 } 274 275 static struct vm_area_struct gate_vma; 276 277 static int __init gate_vma_init(void) 278 { 279 vma_init(&gate_vma, NULL); 280 gate_vma.vm_start = FIXADDR_USER_START; 281 gate_vma.vm_end = FIXADDR_USER_END; 282 gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC; 283 gate_vma.vm_page_prot = __P101; 284 285 return 0; 286 } 287 __initcall(gate_vma_init); 288 289 struct vm_area_struct *get_gate_vma(struct mm_struct *mm) 290 { 291 return &gate_vma; 292 } 293 294 int in_gate_area_no_mm(unsigned long addr) 295 { 296 if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END)) 297 return 1; 298 return 0; 299 } 300 301 int in_gate_area(struct mm_struct *mm, unsigned long addr) 302 { 303 return in_gate_area_no_mm(addr); 304 } 305 306 void ia64_mmu_init(void *my_cpu_data) 307 { 308 unsigned long pta, impl_va_bits; 309 extern void tlb_init(void); 310 311 #ifdef CONFIG_DISABLE_VHPT 312 # define VHPT_ENABLE_BIT 0 313 #else 314 # define VHPT_ENABLE_BIT 1 315 #endif 316 317 /* 318 * Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped 319 * address space. The IA-64 architecture guarantees that at least 50 bits of 320 * virtual address space are implemented but if we pick a large enough page size 321 * (e.g., 64KB), the mapped address space is big enough that it will overlap with 322 * VMLPT. I assume that once we run on machines big enough to warrant 64KB pages, 323 * IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a 324 * problem in practice. Alternatively, we could truncate the top of the mapped 325 * address space to not permit mappings that would overlap with the VMLPT. 326 * --davidm 00/12/06 327 */ 328 # define pte_bits 3 329 # define mapped_space_bits (3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT) 330 /* 331 * The virtual page table has to cover the entire implemented address space within 332 * a region even though not all of this space may be mappable. The reason for 333 * this is that the Access bit and Dirty bit fault handlers perform 334 * non-speculative accesses to the virtual page table, so the address range of the 335 * virtual page table itself needs to be covered by virtual page table. 336 */ 337 # define vmlpt_bits (impl_va_bits - PAGE_SHIFT + pte_bits) 338 # define POW2(n) (1ULL << (n)) 339 340 impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61))); 341 342 if (impl_va_bits < 51 || impl_va_bits > 61) 343 panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1); 344 /* 345 * mapped_space_bits - PAGE_SHIFT is the total number of ptes we need, 346 * which must fit into "vmlpt_bits - pte_bits" slots. Second half of 347 * the test makes sure that our mapped space doesn't overlap the 348 * unimplemented hole in the middle of the region. 349 */ 350 if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) || 351 (mapped_space_bits > impl_va_bits - 1)) 352 panic("Cannot build a big enough virtual-linear page table" 353 " to cover mapped address space.\n" 354 " Try using a smaller page size.\n"); 355 356 357 /* place the VMLPT at the end of each page-table mapped region: */ 358 pta = POW2(61) - POW2(vmlpt_bits); 359 360 /* 361 * Set the (virtually mapped linear) page table address. Bit 362 * 8 selects between the short and long format, bits 2-7 the 363 * size of the table, and bit 0 whether the VHPT walker is 364 * enabled. 365 */ 366 ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT); 367 368 ia64_tlb_init(); 369 370 #ifdef CONFIG_HUGETLB_PAGE 371 ia64_set_rr(HPAGE_REGION_BASE, HPAGE_SHIFT << 2); 372 ia64_srlz_d(); 373 #endif 374 } 375 376 #ifdef CONFIG_VIRTUAL_MEM_MAP 377 int vmemmap_find_next_valid_pfn(int node, int i) 378 { 379 unsigned long end_address, hole_next_pfn; 380 unsigned long stop_address; 381 pg_data_t *pgdat = NODE_DATA(node); 382 383 end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i]; 384 end_address = PAGE_ALIGN(end_address); 385 stop_address = (unsigned long) &vmem_map[pgdat_end_pfn(pgdat)]; 386 387 do { 388 pgd_t *pgd; 389 p4d_t *p4d; 390 pud_t *pud; 391 pmd_t *pmd; 392 pte_t *pte; 393 394 pgd = pgd_offset_k(end_address); 395 if (pgd_none(*pgd)) { 396 end_address += PGDIR_SIZE; 397 continue; 398 } 399 400 p4d = p4d_offset(pgd, end_address); 401 if (p4d_none(*p4d)) { 402 end_address += P4D_SIZE; 403 continue; 404 } 405 406 pud = pud_offset(p4d, end_address); 407 if (pud_none(*pud)) { 408 end_address += PUD_SIZE; 409 continue; 410 } 411 412 pmd = pmd_offset(pud, end_address); 413 if (pmd_none(*pmd)) { 414 end_address += PMD_SIZE; 415 continue; 416 } 417 418 pte = pte_offset_kernel(pmd, end_address); 419 retry_pte: 420 if (pte_none(*pte)) { 421 end_address += PAGE_SIZE; 422 pte++; 423 if ((end_address < stop_address) && 424 (end_address != ALIGN(end_address, 1UL << PMD_SHIFT))) 425 goto retry_pte; 426 continue; 427 } 428 /* Found next valid vmem_map page */ 429 break; 430 } while (end_address < stop_address); 431 432 end_address = min(end_address, stop_address); 433 end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1; 434 hole_next_pfn = end_address / sizeof(struct page); 435 return hole_next_pfn - pgdat->node_start_pfn; 436 } 437 438 int __init create_mem_map_page_table(u64 start, u64 end, void *arg) 439 { 440 unsigned long address, start_page, end_page; 441 struct page *map_start, *map_end; 442 int node; 443 pgd_t *pgd; 444 p4d_t *p4d; 445 pud_t *pud; 446 pmd_t *pmd; 447 pte_t *pte; 448 449 map_start = vmem_map + (__pa(start) >> PAGE_SHIFT); 450 map_end = vmem_map + (__pa(end) >> PAGE_SHIFT); 451 452 start_page = (unsigned long) map_start & PAGE_MASK; 453 end_page = PAGE_ALIGN((unsigned long) map_end); 454 node = paddr_to_nid(__pa(start)); 455 456 for (address = start_page; address < end_page; address += PAGE_SIZE) { 457 pgd = pgd_offset_k(address); 458 if (pgd_none(*pgd)) { 459 p4d = memblock_alloc_node(PAGE_SIZE, PAGE_SIZE, node); 460 if (!p4d) 461 goto err_alloc; 462 pgd_populate(&init_mm, pgd, p4d); 463 } 464 p4d = p4d_offset(pgd, address); 465 466 if (p4d_none(*p4d)) { 467 pud = memblock_alloc_node(PAGE_SIZE, PAGE_SIZE, node); 468 if (!pud) 469 goto err_alloc; 470 p4d_populate(&init_mm, p4d, pud); 471 } 472 pud = pud_offset(p4d, address); 473 474 if (pud_none(*pud)) { 475 pmd = memblock_alloc_node(PAGE_SIZE, PAGE_SIZE, node); 476 if (!pmd) 477 goto err_alloc; 478 pud_populate(&init_mm, pud, pmd); 479 } 480 pmd = pmd_offset(pud, address); 481 482 if (pmd_none(*pmd)) { 483 pte = memblock_alloc_node(PAGE_SIZE, PAGE_SIZE, node); 484 if (!pte) 485 goto err_alloc; 486 pmd_populate_kernel(&init_mm, pmd, pte); 487 } 488 pte = pte_offset_kernel(pmd, address); 489 490 if (pte_none(*pte)) { 491 void *page = memblock_alloc_node(PAGE_SIZE, PAGE_SIZE, 492 node); 493 if (!page) 494 goto err_alloc; 495 set_pte(pte, pfn_pte(__pa(page) >> PAGE_SHIFT, 496 PAGE_KERNEL)); 497 } 498 } 499 return 0; 500 501 err_alloc: 502 panic("%s: Failed to allocate %lu bytes align=0x%lx nid=%d\n", 503 __func__, PAGE_SIZE, PAGE_SIZE, node); 504 return -ENOMEM; 505 } 506 507 struct memmap_init_callback_data { 508 struct page *start; 509 struct page *end; 510 int nid; 511 unsigned long zone; 512 }; 513 514 static int __meminit 515 virtual_memmap_init(u64 start, u64 end, void *arg) 516 { 517 struct memmap_init_callback_data *args; 518 struct page *map_start, *map_end; 519 520 args = (struct memmap_init_callback_data *) arg; 521 map_start = vmem_map + (__pa(start) >> PAGE_SHIFT); 522 map_end = vmem_map + (__pa(end) >> PAGE_SHIFT); 523 524 if (map_start < args->start) 525 map_start = args->start; 526 if (map_end > args->end) 527 map_end = args->end; 528 529 /* 530 * We have to initialize "out of bounds" struct page elements that fit completely 531 * on the same pages that were allocated for the "in bounds" elements because they 532 * may be referenced later (and found to be "reserved"). 533 */ 534 map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1)) / sizeof(struct page); 535 map_end += ((PAGE_ALIGN((unsigned long) map_end) - (unsigned long) map_end) 536 / sizeof(struct page)); 537 538 if (map_start < map_end) 539 memmap_init_zone((unsigned long)(map_end - map_start), 540 args->nid, args->zone, page_to_pfn(map_start), 541 MEMINIT_EARLY, NULL); 542 return 0; 543 } 544 545 void __meminit 546 memmap_init (unsigned long size, int nid, unsigned long zone, 547 unsigned long start_pfn) 548 { 549 if (!vmem_map) { 550 memmap_init_zone(size, nid, zone, start_pfn, 551 MEMINIT_EARLY, NULL); 552 } else { 553 struct page *start; 554 struct memmap_init_callback_data args; 555 556 start = pfn_to_page(start_pfn); 557 args.start = start; 558 args.end = start + size; 559 args.nid = nid; 560 args.zone = zone; 561 562 efi_memmap_walk(virtual_memmap_init, &args); 563 } 564 } 565 566 int 567 ia64_pfn_valid (unsigned long pfn) 568 { 569 char byte; 570 struct page *pg = pfn_to_page(pfn); 571 572 return (__get_user(byte, (char __user *) pg) == 0) 573 && ((((u64)pg & PAGE_MASK) == (((u64)(pg + 1) - 1) & PAGE_MASK)) 574 || (__get_user(byte, (char __user *) (pg + 1) - 1) == 0)); 575 } 576 EXPORT_SYMBOL(ia64_pfn_valid); 577 578 int __init find_largest_hole(u64 start, u64 end, void *arg) 579 { 580 u64 *max_gap = arg; 581 582 static u64 last_end = PAGE_OFFSET; 583 584 /* NOTE: this algorithm assumes efi memmap table is ordered */ 585 586 if (*max_gap < (start - last_end)) 587 *max_gap = start - last_end; 588 last_end = end; 589 return 0; 590 } 591 592 #endif /* CONFIG_VIRTUAL_MEM_MAP */ 593 594 int __init register_active_ranges(u64 start, u64 len, int nid) 595 { 596 u64 end = start + len; 597 598 #ifdef CONFIG_KEXEC 599 if (start > crashk_res.start && start < crashk_res.end) 600 start = crashk_res.end; 601 if (end > crashk_res.start && end < crashk_res.end) 602 end = crashk_res.start; 603 #endif 604 605 if (start < end) 606 memblock_add_node(__pa(start), end - start, nid); 607 return 0; 608 } 609 610 int 611 find_max_min_low_pfn (u64 start, u64 end, void *arg) 612 { 613 unsigned long pfn_start, pfn_end; 614 #ifdef CONFIG_FLATMEM 615 pfn_start = (PAGE_ALIGN(__pa(start))) >> PAGE_SHIFT; 616 pfn_end = (PAGE_ALIGN(__pa(end - 1))) >> PAGE_SHIFT; 617 #else 618 pfn_start = GRANULEROUNDDOWN(__pa(start)) >> PAGE_SHIFT; 619 pfn_end = GRANULEROUNDUP(__pa(end - 1)) >> PAGE_SHIFT; 620 #endif 621 min_low_pfn = min(min_low_pfn, pfn_start); 622 max_low_pfn = max(max_low_pfn, pfn_end); 623 return 0; 624 } 625 626 /* 627 * Boot command-line option "nolwsys" can be used to disable the use of any light-weight 628 * system call handler. When this option is in effect, all fsyscalls will end up bubbling 629 * down into the kernel and calling the normal (heavy-weight) syscall handler. This is 630 * useful for performance testing, but conceivably could also come in handy for debugging 631 * purposes. 632 */ 633 634 static int nolwsys __initdata; 635 636 static int __init 637 nolwsys_setup (char *s) 638 { 639 nolwsys = 1; 640 return 1; 641 } 642 643 __setup("nolwsys", nolwsys_setup); 644 645 void __init 646 mem_init (void) 647 { 648 int i; 649 650 BUG_ON(PTRS_PER_PGD * sizeof(pgd_t) != PAGE_SIZE); 651 BUG_ON(PTRS_PER_PMD * sizeof(pmd_t) != PAGE_SIZE); 652 BUG_ON(PTRS_PER_PTE * sizeof(pte_t) != PAGE_SIZE); 653 654 /* 655 * This needs to be called _after_ the command line has been parsed but 656 * _before_ any drivers that may need the PCI DMA interface are 657 * initialized or bootmem has been freed. 658 */ 659 #ifdef CONFIG_INTEL_IOMMU 660 detect_intel_iommu(); 661 if (!iommu_detected) 662 #endif 663 #ifdef CONFIG_SWIOTLB 664 swiotlb_init(1); 665 #endif 666 667 #ifdef CONFIG_FLATMEM 668 BUG_ON(!mem_map); 669 #endif 670 671 set_max_mapnr(max_low_pfn); 672 high_memory = __va(max_low_pfn * PAGE_SIZE); 673 memblock_free_all(); 674 mem_init_print_info(NULL); 675 676 /* 677 * For fsyscall entrpoints with no light-weight handler, use the ordinary 678 * (heavy-weight) handler, but mark it by setting bit 0, so the fsyscall entry 679 * code can tell them apart. 680 */ 681 for (i = 0; i < NR_syscalls; ++i) { 682 extern unsigned long fsyscall_table[NR_syscalls]; 683 extern unsigned long sys_call_table[NR_syscalls]; 684 685 if (!fsyscall_table[i] || nolwsys) 686 fsyscall_table[i] = sys_call_table[i] | 1; 687 } 688 setup_gate(); 689 } 690 691 #ifdef CONFIG_MEMORY_HOTPLUG 692 int arch_add_memory(int nid, u64 start, u64 size, 693 struct mhp_params *params) 694 { 695 unsigned long start_pfn = start >> PAGE_SHIFT; 696 unsigned long nr_pages = size >> PAGE_SHIFT; 697 int ret; 698 699 if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot)) 700 return -EINVAL; 701 702 ret = __add_pages(nid, start_pfn, nr_pages, params); 703 if (ret) 704 printk("%s: Problem encountered in __add_pages() as ret=%d\n", 705 __func__, ret); 706 707 return ret; 708 } 709 710 void arch_remove_memory(int nid, u64 start, u64 size, 711 struct vmem_altmap *altmap) 712 { 713 unsigned long start_pfn = start >> PAGE_SHIFT; 714 unsigned long nr_pages = size >> PAGE_SHIFT; 715 716 __remove_pages(start_pfn, nr_pages, altmap); 717 } 718 #endif 719