init.c 17.9 KB
Newer Older
1
// SPDX-License-Identifier: GPL-2.0
L
Linus Torvalds 已提交
2 3 4 5 6 7 8 9 10 11 12 13
/*
 * Initialize MMU support.
 *
 * Copyright (C) 1998-2003 Hewlett-Packard Co
 *	David Mosberger-Tang <davidm@hpl.hp.com>
 */
#include <linux/kernel.h>
#include <linux/init.h>

#include <linux/bootmem.h>
#include <linux/efi.h>
#include <linux/elf.h>
T
Tejun Heo 已提交
14
#include <linux/memblock.h>
L
Linus Torvalds 已提交
15
#include <linux/mm.h>
16
#include <linux/sched/signal.h>
L
Linus Torvalds 已提交
17 18 19 20 21 22 23 24
#include <linux/mmzone.h>
#include <linux/module.h>
#include <linux/personality.h>
#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/proc_fs.h>
#include <linux/bitops.h>
25
#include <linux/kexec.h>
L
Linus Torvalds 已提交
26 27 28 29 30 31 32 33 34 35

#include <asm/dma.h>
#include <asm/io.h>
#include <asm/machvec.h>
#include <asm/numa.h>
#include <asm/patch.h>
#include <asm/pgalloc.h>
#include <asm/sal.h>
#include <asm/sections.h>
#include <asm/tlb.h>
36
#include <linux/uaccess.h>
L
Linus Torvalds 已提交
37 38 39 40 41 42 43 44
#include <asm/unistd.h>
#include <asm/mca.h>

extern void ia64_tlb_init (void);

unsigned long MAX_DMA_ADDRESS = PAGE_OFFSET + 0x100000000UL;

#ifdef CONFIG_VIRTUAL_MEM_MAP
45 46
unsigned long VMALLOC_END = VMALLOC_END_INIT;
EXPORT_SYMBOL(VMALLOC_END);
L
Linus Torvalds 已提交
47 48 49 50
struct page *vmem_map;
EXPORT_SYMBOL(vmem_map);
#endif

51
struct page *zero_page_memmap_ptr;	/* map entry for zero page */
L
Linus Torvalds 已提交
52 53 54
EXPORT_SYMBOL(zero_page_memmap_ptr);

void
55
__ia64_sync_icache_dcache (pte_t pte)
L
Linus Torvalds 已提交
56 57 58 59 60 61 62 63 64 65
{
	unsigned long addr;
	struct page *page;

	page = pte_page(pte);
	addr = (unsigned long) page_address(page);

	if (test_bit(PG_arch_1, &page->flags))
		return;				/* i-cache is already coherent with d-cache */

66
	flush_icache_range(addr, addr + (PAGE_SIZE << compound_order(page)));
L
Linus Torvalds 已提交
67 68 69
	set_bit(PG_arch_1, &page->flags);	/* mark page as clean */
}

J
Jan Beulich 已提交
70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88
/*
 * Since DMA is i-cache coherent, any (complete) pages that were written via
 * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to
 * flush them when they get mapped into an executable vm-area.
 */
void
dma_mark_clean(void *addr, size_t size)
{
	unsigned long pg_addr, end;

	pg_addr = PAGE_ALIGN((unsigned long) addr);
	end = (unsigned long) addr + size;
	while (pg_addr + PAGE_SIZE <= end) {
		struct page *page = virt_to_page(pg_addr);
		set_bit(PG_arch_1, &page->flags);
		pg_addr += PAGE_SIZE;
	}
}

L
Linus Torvalds 已提交
89 90 91
inline void
ia64_set_rbs_bot (void)
{
J
Jiri Slaby 已提交
92
	unsigned long stack_size = rlimit_max(RLIMIT_STACK) & -16;
L
Linus Torvalds 已提交
93 94 95

	if (stack_size > MAX_USER_STACK_SIZE)
		stack_size = MAX_USER_STACK_SIZE;
96
	current->thread.rbs_bot = PAGE_ALIGN(current->mm->start_stack - stack_size);
L
Linus Torvalds 已提交
97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116
}

/*
 * This performs some platform-dependent address space initialization.
 * On IA-64, we want to setup the VM area for the register backing
 * store (which grows upwards) and install the gateway page which is
 * used for signal trampolines, etc.
 */
void
ia64_init_addr_space (void)
{
	struct vm_area_struct *vma;

	ia64_set_rbs_bot();

	/*
	 * If we're out of memory and kmem_cache_alloc() returns NULL, we simply ignore
	 * the problem.  When the process attempts to write to the register backing store
	 * for the first time, it will get a SEGFAULT in this case.
	 */
117
	vma = vm_area_alloc(current->mm);
L
Linus Torvalds 已提交
118
	if (vma) {
119
		vma_set_anonymous(vma);
L
Linus Torvalds 已提交
120 121
		vma->vm_start = current->thread.rbs_bot & PAGE_MASK;
		vma->vm_end = vma->vm_start + PAGE_SIZE;
H
Hugh Dickins 已提交
122
		vma->vm_flags = VM_DATA_DEFAULT_FLAGS|VM_GROWSUP|VM_ACCOUNT;
123
		vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
L
Linus Torvalds 已提交
124 125 126
		down_write(&current->mm->mmap_sem);
		if (insert_vm_struct(current->mm, vma)) {
			up_write(&current->mm->mmap_sem);
127
			vm_area_free(vma);
L
Linus Torvalds 已提交
128 129 130 131 132 133 134
			return;
		}
		up_write(&current->mm->mmap_sem);
	}

	/* map NaT-page at address zero to speed up speculative dereferencing of NULL: */
	if (!(current->personality & MMAP_PAGE_ZERO)) {
135
		vma = vm_area_alloc(current->mm);
L
Linus Torvalds 已提交
136
		if (vma) {
137
			vma_set_anonymous(vma);
L
Linus Torvalds 已提交
138 139
			vma->vm_end = PAGE_SIZE;
			vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT);
140 141
			vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO |
					VM_DONTEXPAND | VM_DONTDUMP;
L
Linus Torvalds 已提交
142 143 144
			down_write(&current->mm->mmap_sem);
			if (insert_vm_struct(current->mm, vma)) {
				up_write(&current->mm->mmap_sem);
145
				vm_area_free(vma);
L
Linus Torvalds 已提交
146 147 148 149 150 151 152 153 154 155
				return;
			}
			up_write(&current->mm->mmap_sem);
		}
	}
}

void
free_initmem (void)
{
156
	free_reserved_area(ia64_imva(__init_begin), ia64_imva(__init_end),
157
			   -1, "unused kernel");
L
Linus Torvalds 已提交
158 159
}

160
void __init
L
Linus Torvalds 已提交
161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202
free_initrd_mem (unsigned long start, unsigned long end)
{
	/*
	 * EFI uses 4KB pages while the kernel can use 4KB or bigger.
	 * Thus EFI and the kernel may have different page sizes. It is
	 * therefore possible to have the initrd share the same page as
	 * the end of the kernel (given current setup).
	 *
	 * To avoid freeing/using the wrong page (kernel sized) we:
	 *	- align up the beginning of initrd
	 *	- align down the end of initrd
	 *
	 *  |             |
	 *  |=============| a000
	 *  |             |
	 *  |             |
	 *  |             | 9000
	 *  |/////////////|
	 *  |/////////////|
	 *  |=============| 8000
	 *  |///INITRD////|
	 *  |/////////////|
	 *  |/////////////| 7000
	 *  |             |
	 *  |KKKKKKKKKKKKK|
	 *  |=============| 6000
	 *  |KKKKKKKKKKKKK|
	 *  |KKKKKKKKKKKKK|
	 *  K=kernel using 8KB pages
	 *
	 * In this example, we must free page 8000 ONLY. So we must align up
	 * initrd_start and keep initrd_end as is.
	 */
	start = PAGE_ALIGN(start);
	end = end & PAGE_MASK;

	if (start < end)
		printk(KERN_INFO "Freeing initrd memory: %ldkB freed\n", (end - start) >> 10);

	for (; start < end; start += PAGE_SIZE) {
		if (!virt_addr_valid(start))
			continue;
203
		free_reserved_page(virt_to_page(start));
L
Linus Torvalds 已提交
204 205 206 207 208 209
	}
}

/*
 * This installs a clean page in the kernel's page table.
 */
210
static struct page * __init
L
Linus Torvalds 已提交
211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226
put_kernel_page (struct page *page, unsigned long address, pgprot_t pgprot)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;

	pgd = pgd_offset_k(address);		/* note: this is NOT pgd_offset()! */

	{
		pud = pud_alloc(&init_mm, pgd, address);
		if (!pud)
			goto out;
		pmd = pmd_alloc(&init_mm, pud, address);
		if (!pmd)
			goto out;
H
Hugh Dickins 已提交
227
		pte = pte_alloc_kernel(pmd, address);
L
Linus Torvalds 已提交
228 229
		if (!pte)
			goto out;
H
Hugh Dickins 已提交
230
		if (!pte_none(*pte))
L
Linus Torvalds 已提交
231 232 233
			goto out;
		set_pte(pte, mk_pte(page, pgprot));
	}
H
Hugh Dickins 已提交
234
  out:
L
Linus Torvalds 已提交
235 236 237 238
	/* no need for flush_tlb */
	return page;
}

239
static void __init
L
Linus Torvalds 已提交
240 241 242 243 244
setup_gate (void)
{
	struct page *page;

	/*
245 246 247
	 * Map the gate page twice: once read-only to export the ELF
	 * headers etc. and once execute-only page to enable
	 * privilege-promotion via "epc":
L
Linus Torvalds 已提交
248
	 */
L
Luis R. Rodriguez 已提交
249
	page = virt_to_page(ia64_imva(__start_gate_section));
L
Linus Torvalds 已提交
250 251
	put_kernel_page(page, GATE_ADDR, PAGE_READONLY);
#ifdef HAVE_BUGGY_SEGREL
L
Luis R. Rodriguez 已提交
252
	page = virt_to_page(ia64_imva(__start_gate_section + PAGE_SIZE));
L
Linus Torvalds 已提交
253 254 255
	put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE);
#else
	put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE);
256 257 258 259 260 261 262 263 264 265 266 267 268 269
	/* Fill in the holes (if any) with read-only zero pages: */
	{
		unsigned long addr;

		for (addr = GATE_ADDR + PAGE_SIZE;
		     addr < GATE_ADDR + PERCPU_PAGE_SIZE;
		     addr += PAGE_SIZE)
		{
			put_kernel_page(ZERO_PAGE(0), addr,
					PAGE_READONLY);
			put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE,
					PAGE_READONLY);
		}
	}
L
Linus Torvalds 已提交
270 271 272 273
#endif
	ia64_patch_gate();
}

274 275 276 277
static struct vm_area_struct gate_vma;

static int __init gate_vma_init(void)
{
278
	vma_init(&gate_vma, NULL);
279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304
	gate_vma.vm_start = FIXADDR_USER_START;
	gate_vma.vm_end = FIXADDR_USER_END;
	gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
	gate_vma.vm_page_prot = __P101;

	return 0;
}
__initcall(gate_vma_init);

struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
{
	return &gate_vma;
}

int in_gate_area_no_mm(unsigned long addr)
{
	if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END))
		return 1;
	return 0;
}

int in_gate_area(struct mm_struct *mm, unsigned long addr)
{
	return in_gate_area_no_mm(addr);
}

305
void ia64_mmu_init(void *my_cpu_data)
L
Linus Torvalds 已提交
306
{
307
	unsigned long pta, impl_va_bits;
308
	extern void tlb_init(void);
L
Linus Torvalds 已提交
309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342

#ifdef CONFIG_DISABLE_VHPT
#	define VHPT_ENABLE_BIT	0
#else
#	define VHPT_ENABLE_BIT	1
#endif

	/*
	 * Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped
	 * address space.  The IA-64 architecture guarantees that at least 50 bits of
	 * virtual address space are implemented but if we pick a large enough page size
	 * (e.g., 64KB), the mapped address space is big enough that it will overlap with
	 * VMLPT.  I assume that once we run on machines big enough to warrant 64KB pages,
	 * IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a
	 * problem in practice.  Alternatively, we could truncate the top of the mapped
	 * address space to not permit mappings that would overlap with the VMLPT.
	 * --davidm 00/12/06
	 */
#	define pte_bits			3
#	define mapped_space_bits	(3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT)
	/*
	 * The virtual page table has to cover the entire implemented address space within
	 * a region even though not all of this space may be mappable.  The reason for
	 * this is that the Access bit and Dirty bit fault handlers perform
	 * non-speculative accesses to the virtual page table, so the address range of the
	 * virtual page table itself needs to be covered by virtual page table.
	 */
#	define vmlpt_bits		(impl_va_bits - PAGE_SHIFT + pte_bits)
#	define POW2(n)			(1ULL << (n))

	impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61)));

	if (impl_va_bits < 51 || impl_va_bits > 61)
		panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1);
P
Peter Chubb 已提交
343 344 345 346 347 348 349 350 351 352 353 354
	/*
	 * mapped_space_bits - PAGE_SHIFT is the total number of ptes we need,
	 * which must fit into "vmlpt_bits - pte_bits" slots. Second half of
	 * the test makes sure that our mapped space doesn't overlap the
	 * unimplemented hole in the middle of the region.
	 */
	if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) ||
	    (mapped_space_bits > impl_va_bits - 1))
		panic("Cannot build a big enough virtual-linear page table"
		      " to cover mapped address space.\n"
		      " Try using a smaller page size.\n");

L
Linus Torvalds 已提交
355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375

	/* place the VMLPT at the end of each page-table mapped region: */
	pta = POW2(61) - POW2(vmlpt_bits);

	/*
	 * Set the (virtually mapped linear) page table address.  Bit
	 * 8 selects between the short and long format, bits 2-7 the
	 * size of the table, and bit 0 whether the VHPT walker is
	 * enabled.
	 */
	ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT);

	ia64_tlb_init();

#ifdef	CONFIG_HUGETLB_PAGE
	ia64_set_rr(HPAGE_REGION_BASE, HPAGE_SHIFT << 2);
	ia64_srlz_d();
#endif
}

#ifdef CONFIG_VIRTUAL_MEM_MAP
376 377 378 379 380 381 382 383
int vmemmap_find_next_valid_pfn(int node, int i)
{
	unsigned long end_address, hole_next_pfn;
	unsigned long stop_address;
	pg_data_t *pgdat = NODE_DATA(node);

	end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i];
	end_address = PAGE_ALIGN(end_address);
384
	stop_address = (unsigned long) &vmem_map[pgdat_end_pfn(pgdat)];
385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428

	do {
		pgd_t *pgd;
		pud_t *pud;
		pmd_t *pmd;
		pte_t *pte;

		pgd = pgd_offset_k(end_address);
		if (pgd_none(*pgd)) {
			end_address += PGDIR_SIZE;
			continue;
		}

		pud = pud_offset(pgd, end_address);
		if (pud_none(*pud)) {
			end_address += PUD_SIZE;
			continue;
		}

		pmd = pmd_offset(pud, end_address);
		if (pmd_none(*pmd)) {
			end_address += PMD_SIZE;
			continue;
		}

		pte = pte_offset_kernel(pmd, end_address);
retry_pte:
		if (pte_none(*pte)) {
			end_address += PAGE_SIZE;
			pte++;
			if ((end_address < stop_address) &&
			    (end_address != ALIGN(end_address, 1UL << PMD_SHIFT)))
				goto retry_pte;
			continue;
		}
		/* Found next valid vmem_map page */
		break;
	} while (end_address < stop_address);

	end_address = min(end_address, stop_address);
	end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1;
	hole_next_pfn = end_address / sizeof(struct page);
	return hole_next_pfn - pgdat->node_start_pfn;
}
L
Linus Torvalds 已提交
429

430
int __init create_mem_map_page_table(u64 start, u64 end, void *arg)
L
Linus Torvalds 已提交
431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474
{
	unsigned long address, start_page, end_page;
	struct page *map_start, *map_end;
	int node;
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;

	map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
	map_end   = vmem_map + (__pa(end) >> PAGE_SHIFT);

	start_page = (unsigned long) map_start & PAGE_MASK;
	end_page = PAGE_ALIGN((unsigned long) map_end);
	node = paddr_to_nid(__pa(start));

	for (address = start_page; address < end_page; address += PAGE_SIZE) {
		pgd = pgd_offset_k(address);
		if (pgd_none(*pgd))
			pgd_populate(&init_mm, pgd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
		pud = pud_offset(pgd, address);

		if (pud_none(*pud))
			pud_populate(&init_mm, pud, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
		pmd = pmd_offset(pud, address);

		if (pmd_none(*pmd))
			pmd_populate_kernel(&init_mm, pmd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
		pte = pte_offset_kernel(pmd, address);

		if (pte_none(*pte))
			set_pte(pte, pfn_pte(__pa(alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)) >> PAGE_SHIFT,
					     PAGE_KERNEL));
	}
	return 0;
}

struct memmap_init_callback_data {
	struct page *start;
	struct page *end;
	int nid;
	unsigned long zone;
};

475
static int __meminit
476
virtual_memmap_init(u64 start, u64 end, void *arg)
L
Linus Torvalds 已提交
477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500
{
	struct memmap_init_callback_data *args;
	struct page *map_start, *map_end;

	args = (struct memmap_init_callback_data *) arg;
	map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
	map_end   = vmem_map + (__pa(end) >> PAGE_SHIFT);

	if (map_start < args->start)
		map_start = args->start;
	if (map_end > args->end)
		map_end = args->end;

	/*
	 * We have to initialize "out of bounds" struct page elements that fit completely
	 * on the same pages that were allocated for the "in bounds" elements because they
	 * may be referenced later (and found to be "reserved").
	 */
	map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1)) / sizeof(struct page);
	map_end += ((PAGE_ALIGN((unsigned long) map_end) - (unsigned long) map_end)
		    / sizeof(struct page));

	if (map_start < map_end)
		memmap_init_zone((unsigned long)(map_end - map_start),
D
Dave Hansen 已提交
501
				 args->nid, args->zone, page_to_pfn(map_start),
502
				 MEMMAP_EARLY, NULL);
L
Linus Torvalds 已提交
503 504 505
	return 0;
}

506
void __meminit
L
Linus Torvalds 已提交
507 508 509
memmap_init (unsigned long size, int nid, unsigned long zone,
	     unsigned long start_pfn)
{
510 511 512 513
	if (!vmem_map) {
		memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY,
				NULL);
	} else {
L
Linus Torvalds 已提交
514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538
		struct page *start;
		struct memmap_init_callback_data args;

		start = pfn_to_page(start_pfn);
		args.start = start;
		args.end = start + size;
		args.nid = nid;
		args.zone = zone;

		efi_memmap_walk(virtual_memmap_init, &args);
	}
}

int
ia64_pfn_valid (unsigned long pfn)
{
	char byte;
	struct page *pg = pfn_to_page(pfn);

	return     (__get_user(byte, (char __user *) pg) == 0)
		&& ((((u64)pg & PAGE_MASK) == (((u64)(pg + 1) - 1) & PAGE_MASK))
			|| (__get_user(byte, (char __user *) (pg + 1) - 1) == 0));
}
EXPORT_SYMBOL(ia64_pfn_valid);

539
int __init find_largest_hole(u64 start, u64 end, void *arg)
L
Linus Torvalds 已提交
540 541 542 543 544 545 546 547 548 549 550 551
{
	u64 *max_gap = arg;

	static u64 last_end = PAGE_OFFSET;

	/* NOTE: this algorithm assumes efi memmap table is ordered */

	if (*max_gap < (start - last_end))
		*max_gap = start - last_end;
	last_end = end;
	return 0;
}
552

553 554
#endif /* CONFIG_VIRTUAL_MEM_MAP */

555
int __init register_active_ranges(u64 start, u64 len, int nid)
556
{
557
	u64 end = start + len;
558 559 560 561 562 563 564 565 566

#ifdef CONFIG_KEXEC
	if (start > crashk_res.start && start < crashk_res.end)
		start = crashk_res.end;
	if (end > crashk_res.start && end < crashk_res.end)
		end = crashk_res.start;
#endif

	if (start < end)
T
Tejun Heo 已提交
567
		memblock_add_node(__pa(start), end - start, nid);
568 569
	return 0;
}
L
Linus Torvalds 已提交
570

571
int
572
find_max_min_low_pfn (u64 start, u64 end, void *arg)
573 574 575 576 577 578 579 580 581 582 583 584 585 586
{
	unsigned long pfn_start, pfn_end;
#ifdef CONFIG_FLATMEM
	pfn_start = (PAGE_ALIGN(__pa(start))) >> PAGE_SHIFT;
	pfn_end = (PAGE_ALIGN(__pa(end - 1))) >> PAGE_SHIFT;
#else
	pfn_start = GRANULEROUNDDOWN(__pa(start)) >> PAGE_SHIFT;
	pfn_end = GRANULEROUNDUP(__pa(end - 1)) >> PAGE_SHIFT;
#endif
	min_low_pfn = min(min_low_pfn, pfn_start);
	max_low_pfn = max(max_low_pfn, pfn_end);
	return 0;
}

L
Linus Torvalds 已提交
587 588 589 590 591 592 593 594
/*
 * Boot command-line option "nolwsys" can be used to disable the use of any light-weight
 * system call handler.  When this option is in effect, all fsyscalls will end up bubbling
 * down into the kernel and calling the normal (heavy-weight) syscall handler.  This is
 * useful for performance testing, but conceivably could also come in handy for debugging
 * purposes.
 */

595
static int nolwsys __initdata;
L
Linus Torvalds 已提交
596 597 598 599 600 601 602 603 604 605

static int __init
nolwsys_setup (char *s)
{
	nolwsys = 1;
	return 1;
}

__setup("nolwsys", nolwsys_setup);

606
void __init
L
Linus Torvalds 已提交
607 608 609 610
mem_init (void)
{
	int i;

611 612 613 614
	BUG_ON(PTRS_PER_PGD * sizeof(pgd_t) != PAGE_SIZE);
	BUG_ON(PTRS_PER_PMD * sizeof(pmd_t) != PAGE_SIZE);
	BUG_ON(PTRS_PER_PTE * sizeof(pte_t) != PAGE_SIZE);

L
Linus Torvalds 已提交
615 616 617 618 619 620 621 622 623
#ifdef CONFIG_PCI
	/*
	 * This needs to be called _after_ the command line has been parsed but _before_
	 * any drivers that may need the PCI DMA interface are initialized or bootmem has
	 * been freed.
	 */
	platform_dma_init();
#endif

624
#ifdef CONFIG_FLATMEM
S
Stoyan Gaydarov 已提交
625
	BUG_ON(!mem_map);
L
Linus Torvalds 已提交
626 627
#endif

628
	set_max_mapnr(max_low_pfn);
L
Linus Torvalds 已提交
629
	high_memory = __va(max_low_pfn * PAGE_SIZE);
630
	free_all_bootmem();
631
	mem_init_print_info(NULL);
L
Linus Torvalds 已提交
632 633 634 635 636 637 638

	/*
	 * For fsyscall entrpoints with no light-weight handler, use the ordinary
	 * (heavy-weight) handler, but mark it by setting bit 0, so the fsyscall entry
	 * code can tell them apart.
	 */
	for (i = 0; i < NR_syscalls; ++i) {
L
Luis R. Rodriguez 已提交
639
		extern unsigned long fsyscall_table[NR_syscalls];
L
Linus Torvalds 已提交
640 641 642 643 644 645 646
		extern unsigned long sys_call_table[NR_syscalls];

		if (!fsyscall_table[i] || nolwsys)
			fsyscall_table[i] = sys_call_table[i] | 1;
	}
	setup_gate();
}
647 648

#ifdef CONFIG_MEMORY_HOTPLUG
649 650
int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
		bool want_memblock)
651 652 653 654 655
{
	unsigned long start_pfn = start >> PAGE_SHIFT;
	unsigned long nr_pages = size >> PAGE_SHIFT;
	int ret;

656
	ret = __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
657 658
	if (ret)
		printk("%s: Problem encountered in __add_pages() as ret=%d\n",
659
		       __func__,  ret);
660 661 662

	return ret;
}
663 664

#ifdef CONFIG_MEMORY_HOTREMOVE
665
int arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
666 667 668 669 670 671 672
{
	unsigned long start_pfn = start >> PAGE_SHIFT;
	unsigned long nr_pages = size >> PAGE_SHIFT;
	struct zone *zone;
	int ret;

	zone = page_zone(pfn_to_page(start_pfn));
673
	ret = __remove_pages(zone, start_pfn, nr_pages, altmap);
674 675 676 677 678 679 680
	if (ret)
		pr_warn("%s: Problem encountered in __remove_pages() as"
			" ret=%d\n", __func__,  ret);

	return ret;
}
#endif
681
#endif