xref: /openbmc/linux/arch/ia64/mm/init.c (revision 545e4006)
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/mm.h>
14 #include <linux/mmzone.h>
15 #include <linux/module.h>
16 #include <linux/personality.h>
17 #include <linux/reboot.h>
18 #include <linux/slab.h>
19 #include <linux/swap.h>
20 #include <linux/proc_fs.h>
21 #include <linux/bitops.h>
22 #include <linux/kexec.h>
23 
24 #include <asm/a.out.h>
25 #include <asm/dma.h>
26 #include <asm/ia32.h>
27 #include <asm/io.h>
28 #include <asm/machvec.h>
29 #include <asm/numa.h>
30 #include <asm/patch.h>
31 #include <asm/pgalloc.h>
32 #include <asm/sal.h>
33 #include <asm/sections.h>
34 #include <asm/system.h>
35 #include <asm/tlb.h>
36 #include <asm/uaccess.h>
37 #include <asm/unistd.h>
38 #include <asm/mca.h>
39 
40 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
41 
42 extern void ia64_tlb_init (void);
43 
44 unsigned long MAX_DMA_ADDRESS = PAGE_OFFSET + 0x100000000UL;
45 
46 #ifdef CONFIG_VIRTUAL_MEM_MAP
47 unsigned long vmalloc_end = VMALLOC_END_INIT;
48 EXPORT_SYMBOL(vmalloc_end);
49 struct page *vmem_map;
50 EXPORT_SYMBOL(vmem_map);
51 #endif
52 
53 struct page *zero_page_memmap_ptr;	/* map entry for zero page */
54 EXPORT_SYMBOL(zero_page_memmap_ptr);
55 
56 void
57 __ia64_sync_icache_dcache (pte_t pte)
58 {
59 	unsigned long addr;
60 	struct page *page;
61 
62 	page = pte_page(pte);
63 	addr = (unsigned long) page_address(page);
64 
65 	if (test_bit(PG_arch_1, &page->flags))
66 		return;				/* i-cache is already coherent with d-cache */
67 
68 	flush_icache_range(addr, addr + (PAGE_SIZE << compound_order(page)));
69 	set_bit(PG_arch_1, &page->flags);	/* mark page as clean */
70 }
71 
72 /*
73  * Since DMA is i-cache coherent, any (complete) pages that were written via
74  * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to
75  * flush them when they get mapped into an executable vm-area.
76  */
77 void
78 dma_mark_clean(void *addr, size_t size)
79 {
80 	unsigned long pg_addr, end;
81 
82 	pg_addr = PAGE_ALIGN((unsigned long) addr);
83 	end = (unsigned long) addr + size;
84 	while (pg_addr + PAGE_SIZE <= end) {
85 		struct page *page = virt_to_page(pg_addr);
86 		set_bit(PG_arch_1, &page->flags);
87 		pg_addr += PAGE_SIZE;
88 	}
89 }
90 
91 inline void
92 ia64_set_rbs_bot (void)
93 {
94 	unsigned long stack_size = current->signal->rlim[RLIMIT_STACK].rlim_max & -16;
95 
96 	if (stack_size > MAX_USER_STACK_SIZE)
97 		stack_size = MAX_USER_STACK_SIZE;
98 	current->thread.rbs_bot = PAGE_ALIGN(current->mm->start_stack - stack_size);
99 }
100 
101 /*
102  * This performs some platform-dependent address space initialization.
103  * On IA-64, we want to setup the VM area for the register backing
104  * store (which grows upwards) and install the gateway page which is
105  * used for signal trampolines, etc.
106  */
107 void
108 ia64_init_addr_space (void)
109 {
110 	struct vm_area_struct *vma;
111 
112 	ia64_set_rbs_bot();
113 
114 	/*
115 	 * If we're out of memory and kmem_cache_alloc() returns NULL, we simply ignore
116 	 * the problem.  When the process attempts to write to the register backing store
117 	 * for the first time, it will get a SEGFAULT in this case.
118 	 */
119 	vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
120 	if (vma) {
121 		vma->vm_mm = current->mm;
122 		vma->vm_start = current->thread.rbs_bot & PAGE_MASK;
123 		vma->vm_end = vma->vm_start + PAGE_SIZE;
124 		vma->vm_flags = VM_DATA_DEFAULT_FLAGS|VM_GROWSUP|VM_ACCOUNT;
125 		vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
126 		down_write(&current->mm->mmap_sem);
127 		if (insert_vm_struct(current->mm, vma)) {
128 			up_write(&current->mm->mmap_sem);
129 			kmem_cache_free(vm_area_cachep, vma);
130 			return;
131 		}
132 		up_write(&current->mm->mmap_sem);
133 	}
134 
135 	/* map NaT-page at address zero to speed up speculative dereferencing of NULL: */
136 	if (!(current->personality & MMAP_PAGE_ZERO)) {
137 		vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
138 		if (vma) {
139 			vma->vm_mm = current->mm;
140 			vma->vm_end = PAGE_SIZE;
141 			vma->vm_page_prot = __pgprot(pgprot_val(PAGE_READONLY) | _PAGE_MA_NAT);
142 			vma->vm_flags = VM_READ | VM_MAYREAD | VM_IO | VM_RESERVED;
143 			down_write(&current->mm->mmap_sem);
144 			if (insert_vm_struct(current->mm, vma)) {
145 				up_write(&current->mm->mmap_sem);
146 				kmem_cache_free(vm_area_cachep, vma);
147 				return;
148 			}
149 			up_write(&current->mm->mmap_sem);
150 		}
151 	}
152 }
153 
154 void
155 free_initmem (void)
156 {
157 	unsigned long addr, eaddr;
158 
159 	addr = (unsigned long) ia64_imva(__init_begin);
160 	eaddr = (unsigned long) ia64_imva(__init_end);
161 	while (addr < eaddr) {
162 		ClearPageReserved(virt_to_page(addr));
163 		init_page_count(virt_to_page(addr));
164 		free_page(addr);
165 		++totalram_pages;
166 		addr += PAGE_SIZE;
167 	}
168 	printk(KERN_INFO "Freeing unused kernel memory: %ldkB freed\n",
169 	       (__init_end - __init_begin) >> 10);
170 }
171 
172 void __init
173 free_initrd_mem (unsigned long start, unsigned long end)
174 {
175 	struct page *page;
176 	/*
177 	 * EFI uses 4KB pages while the kernel can use 4KB or bigger.
178 	 * Thus EFI and the kernel may have different page sizes. It is
179 	 * therefore possible to have the initrd share the same page as
180 	 * the end of the kernel (given current setup).
181 	 *
182 	 * To avoid freeing/using the wrong page (kernel sized) we:
183 	 *	- align up the beginning of initrd
184 	 *	- align down the end of initrd
185 	 *
186 	 *  |             |
187 	 *  |=============| a000
188 	 *  |             |
189 	 *  |             |
190 	 *  |             | 9000
191 	 *  |/////////////|
192 	 *  |/////////////|
193 	 *  |=============| 8000
194 	 *  |///INITRD////|
195 	 *  |/////////////|
196 	 *  |/////////////| 7000
197 	 *  |             |
198 	 *  |KKKKKKKKKKKKK|
199 	 *  |=============| 6000
200 	 *  |KKKKKKKKKKKKK|
201 	 *  |KKKKKKKKKKKKK|
202 	 *  K=kernel using 8KB pages
203 	 *
204 	 * In this example, we must free page 8000 ONLY. So we must align up
205 	 * initrd_start and keep initrd_end as is.
206 	 */
207 	start = PAGE_ALIGN(start);
208 	end = end & PAGE_MASK;
209 
210 	if (start < end)
211 		printk(KERN_INFO "Freeing initrd memory: %ldkB freed\n", (end - start) >> 10);
212 
213 	for (; start < end; start += PAGE_SIZE) {
214 		if (!virt_addr_valid(start))
215 			continue;
216 		page = virt_to_page(start);
217 		ClearPageReserved(page);
218 		init_page_count(page);
219 		free_page(start);
220 		++totalram_pages;
221 	}
222 }
223 
224 /*
225  * This installs a clean page in the kernel's page table.
226  */
227 static struct page * __init
228 put_kernel_page (struct page *page, unsigned long address, pgprot_t pgprot)
229 {
230 	pgd_t *pgd;
231 	pud_t *pud;
232 	pmd_t *pmd;
233 	pte_t *pte;
234 
235 	if (!PageReserved(page))
236 		printk(KERN_ERR "put_kernel_page: page at 0x%p not in reserved memory\n",
237 		       page_address(page));
238 
239 	pgd = pgd_offset_k(address);		/* note: this is NOT pgd_offset()! */
240 
241 	{
242 		pud = pud_alloc(&init_mm, pgd, address);
243 		if (!pud)
244 			goto out;
245 		pmd = pmd_alloc(&init_mm, pud, address);
246 		if (!pmd)
247 			goto out;
248 		pte = pte_alloc_kernel(pmd, address);
249 		if (!pte)
250 			goto out;
251 		if (!pte_none(*pte))
252 			goto out;
253 		set_pte(pte, mk_pte(page, pgprot));
254 	}
255   out:
256 	/* no need for flush_tlb */
257 	return page;
258 }
259 
260 static void __init
261 setup_gate (void)
262 {
263 	struct page *page;
264 
265 	/*
266 	 * Map the gate page twice: once read-only to export the ELF
267 	 * headers etc. and once execute-only page to enable
268 	 * privilege-promotion via "epc":
269 	 */
270 	page = virt_to_page(ia64_imva(__start_gate_section));
271 	put_kernel_page(page, GATE_ADDR, PAGE_READONLY);
272 #ifdef HAVE_BUGGY_SEGREL
273 	page = virt_to_page(ia64_imva(__start_gate_section + PAGE_SIZE));
274 	put_kernel_page(page, GATE_ADDR + PAGE_SIZE, PAGE_GATE);
275 #else
276 	put_kernel_page(page, GATE_ADDR + PERCPU_PAGE_SIZE, PAGE_GATE);
277 	/* Fill in the holes (if any) with read-only zero pages: */
278 	{
279 		unsigned long addr;
280 
281 		for (addr = GATE_ADDR + PAGE_SIZE;
282 		     addr < GATE_ADDR + PERCPU_PAGE_SIZE;
283 		     addr += PAGE_SIZE)
284 		{
285 			put_kernel_page(ZERO_PAGE(0), addr,
286 					PAGE_READONLY);
287 			put_kernel_page(ZERO_PAGE(0), addr + PERCPU_PAGE_SIZE,
288 					PAGE_READONLY);
289 		}
290 	}
291 #endif
292 	ia64_patch_gate();
293 }
294 
295 void __devinit
296 ia64_mmu_init (void *my_cpu_data)
297 {
298 	unsigned long pta, impl_va_bits;
299 	extern void __devinit tlb_init (void);
300 
301 #ifdef CONFIG_DISABLE_VHPT
302 #	define VHPT_ENABLE_BIT	0
303 #else
304 #	define VHPT_ENABLE_BIT	1
305 #endif
306 
307 	/*
308 	 * Check if the virtually mapped linear page table (VMLPT) overlaps with a mapped
309 	 * address space.  The IA-64 architecture guarantees that at least 50 bits of
310 	 * virtual address space are implemented but if we pick a large enough page size
311 	 * (e.g., 64KB), the mapped address space is big enough that it will overlap with
312 	 * VMLPT.  I assume that once we run on machines big enough to warrant 64KB pages,
313 	 * IMPL_VA_MSB will be significantly bigger, so this is unlikely to become a
314 	 * problem in practice.  Alternatively, we could truncate the top of the mapped
315 	 * address space to not permit mappings that would overlap with the VMLPT.
316 	 * --davidm 00/12/06
317 	 */
318 #	define pte_bits			3
319 #	define mapped_space_bits	(3*(PAGE_SHIFT - pte_bits) + PAGE_SHIFT)
320 	/*
321 	 * The virtual page table has to cover the entire implemented address space within
322 	 * a region even though not all of this space may be mappable.  The reason for
323 	 * this is that the Access bit and Dirty bit fault handlers perform
324 	 * non-speculative accesses to the virtual page table, so the address range of the
325 	 * virtual page table itself needs to be covered by virtual page table.
326 	 */
327 #	define vmlpt_bits		(impl_va_bits - PAGE_SHIFT + pte_bits)
328 #	define POW2(n)			(1ULL << (n))
329 
330 	impl_va_bits = ffz(~(local_cpu_data->unimpl_va_mask | (7UL << 61)));
331 
332 	if (impl_va_bits < 51 || impl_va_bits > 61)
333 		panic("CPU has bogus IMPL_VA_MSB value of %lu!\n", impl_va_bits - 1);
334 	/*
335 	 * mapped_space_bits - PAGE_SHIFT is the total number of ptes we need,
336 	 * which must fit into "vmlpt_bits - pte_bits" slots. Second half of
337 	 * the test makes sure that our mapped space doesn't overlap the
338 	 * unimplemented hole in the middle of the region.
339 	 */
340 	if ((mapped_space_bits - PAGE_SHIFT > vmlpt_bits - pte_bits) ||
341 	    (mapped_space_bits > impl_va_bits - 1))
342 		panic("Cannot build a big enough virtual-linear page table"
343 		      " to cover mapped address space.\n"
344 		      " Try using a smaller page size.\n");
345 
346 
347 	/* place the VMLPT at the end of each page-table mapped region: */
348 	pta = POW2(61) - POW2(vmlpt_bits);
349 
350 	/*
351 	 * Set the (virtually mapped linear) page table address.  Bit
352 	 * 8 selects between the short and long format, bits 2-7 the
353 	 * size of the table, and bit 0 whether the VHPT walker is
354 	 * enabled.
355 	 */
356 	ia64_set_pta(pta | (0 << 8) | (vmlpt_bits << 2) | VHPT_ENABLE_BIT);
357 
358 	ia64_tlb_init();
359 
360 #ifdef	CONFIG_HUGETLB_PAGE
361 	ia64_set_rr(HPAGE_REGION_BASE, HPAGE_SHIFT << 2);
362 	ia64_srlz_d();
363 #endif
364 }
365 
366 #ifdef CONFIG_VIRTUAL_MEM_MAP
367 int vmemmap_find_next_valid_pfn(int node, int i)
368 {
369 	unsigned long end_address, hole_next_pfn;
370 	unsigned long stop_address;
371 	pg_data_t *pgdat = NODE_DATA(node);
372 
373 	end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i];
374 	end_address = PAGE_ALIGN(end_address);
375 
376 	stop_address = (unsigned long) &vmem_map[
377 		pgdat->node_start_pfn + pgdat->node_spanned_pages];
378 
379 	do {
380 		pgd_t *pgd;
381 		pud_t *pud;
382 		pmd_t *pmd;
383 		pte_t *pte;
384 
385 		pgd = pgd_offset_k(end_address);
386 		if (pgd_none(*pgd)) {
387 			end_address += PGDIR_SIZE;
388 			continue;
389 		}
390 
391 		pud = pud_offset(pgd, end_address);
392 		if (pud_none(*pud)) {
393 			end_address += PUD_SIZE;
394 			continue;
395 		}
396 
397 		pmd = pmd_offset(pud, end_address);
398 		if (pmd_none(*pmd)) {
399 			end_address += PMD_SIZE;
400 			continue;
401 		}
402 
403 		pte = pte_offset_kernel(pmd, end_address);
404 retry_pte:
405 		if (pte_none(*pte)) {
406 			end_address += PAGE_SIZE;
407 			pte++;
408 			if ((end_address < stop_address) &&
409 			    (end_address != ALIGN(end_address, 1UL << PMD_SHIFT)))
410 				goto retry_pte;
411 			continue;
412 		}
413 		/* Found next valid vmem_map page */
414 		break;
415 	} while (end_address < stop_address);
416 
417 	end_address = min(end_address, stop_address);
418 	end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1;
419 	hole_next_pfn = end_address / sizeof(struct page);
420 	return hole_next_pfn - pgdat->node_start_pfn;
421 }
422 
423 int __init
424 create_mem_map_page_table (u64 start, u64 end, void *arg)
425 {
426 	unsigned long address, start_page, end_page;
427 	struct page *map_start, *map_end;
428 	int node;
429 	pgd_t *pgd;
430 	pud_t *pud;
431 	pmd_t *pmd;
432 	pte_t *pte;
433 
434 	map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
435 	map_end   = vmem_map + (__pa(end) >> PAGE_SHIFT);
436 
437 	start_page = (unsigned long) map_start & PAGE_MASK;
438 	end_page = PAGE_ALIGN((unsigned long) map_end);
439 	node = paddr_to_nid(__pa(start));
440 
441 	for (address = start_page; address < end_page; address += PAGE_SIZE) {
442 		pgd = pgd_offset_k(address);
443 		if (pgd_none(*pgd))
444 			pgd_populate(&init_mm, pgd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
445 		pud = pud_offset(pgd, address);
446 
447 		if (pud_none(*pud))
448 			pud_populate(&init_mm, pud, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
449 		pmd = pmd_offset(pud, address);
450 
451 		if (pmd_none(*pmd))
452 			pmd_populate_kernel(&init_mm, pmd, alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE));
453 		pte = pte_offset_kernel(pmd, address);
454 
455 		if (pte_none(*pte))
456 			set_pte(pte, pfn_pte(__pa(alloc_bootmem_pages_node(NODE_DATA(node), PAGE_SIZE)) >> PAGE_SHIFT,
457 					     PAGE_KERNEL));
458 	}
459 	return 0;
460 }
461 
462 struct memmap_init_callback_data {
463 	struct page *start;
464 	struct page *end;
465 	int nid;
466 	unsigned long zone;
467 };
468 
469 static int __meminit
470 virtual_memmap_init (u64 start, u64 end, void *arg)
471 {
472 	struct memmap_init_callback_data *args;
473 	struct page *map_start, *map_end;
474 
475 	args = (struct memmap_init_callback_data *) arg;
476 	map_start = vmem_map + (__pa(start) >> PAGE_SHIFT);
477 	map_end   = vmem_map + (__pa(end) >> PAGE_SHIFT);
478 
479 	if (map_start < args->start)
480 		map_start = args->start;
481 	if (map_end > args->end)
482 		map_end = args->end;
483 
484 	/*
485 	 * We have to initialize "out of bounds" struct page elements that fit completely
486 	 * on the same pages that were allocated for the "in bounds" elements because they
487 	 * may be referenced later (and found to be "reserved").
488 	 */
489 	map_start -= ((unsigned long) map_start & (PAGE_SIZE - 1)) / sizeof(struct page);
490 	map_end += ((PAGE_ALIGN((unsigned long) map_end) - (unsigned long) map_end)
491 		    / sizeof(struct page));
492 
493 	if (map_start < map_end)
494 		memmap_init_zone((unsigned long)(map_end - map_start),
495 				 args->nid, args->zone, page_to_pfn(map_start),
496 				 MEMMAP_EARLY);
497 	return 0;
498 }
499 
500 void __meminit
501 memmap_init (unsigned long size, int nid, unsigned long zone,
502 	     unsigned long start_pfn)
503 {
504 	if (!vmem_map)
505 		memmap_init_zone(size, nid, zone, start_pfn, MEMMAP_EARLY);
506 	else {
507 		struct page *start;
508 		struct memmap_init_callback_data args;
509 
510 		start = pfn_to_page(start_pfn);
511 		args.start = start;
512 		args.end = start + size;
513 		args.nid = nid;
514 		args.zone = zone;
515 
516 		efi_memmap_walk(virtual_memmap_init, &args);
517 	}
518 }
519 
520 int
521 ia64_pfn_valid (unsigned long pfn)
522 {
523 	char byte;
524 	struct page *pg = pfn_to_page(pfn);
525 
526 	return     (__get_user(byte, (char __user *) pg) == 0)
527 		&& ((((u64)pg & PAGE_MASK) == (((u64)(pg + 1) - 1) & PAGE_MASK))
528 			|| (__get_user(byte, (char __user *) (pg + 1) - 1) == 0));
529 }
530 EXPORT_SYMBOL(ia64_pfn_valid);
531 
532 int __init
533 find_largest_hole (u64 start, u64 end, void *arg)
534 {
535 	u64 *max_gap = arg;
536 
537 	static u64 last_end = PAGE_OFFSET;
538 
539 	/* NOTE: this algorithm assumes efi memmap table is ordered */
540 
541 	if (*max_gap < (start - last_end))
542 		*max_gap = start - last_end;
543 	last_end = end;
544 	return 0;
545 }
546 
547 #endif /* CONFIG_VIRTUAL_MEM_MAP */
548 
549 int __init
550 register_active_ranges(u64 start, u64 len, int nid)
551 {
552 	u64 end = start + len;
553 
554 #ifdef CONFIG_KEXEC
555 	if (start > crashk_res.start && start < crashk_res.end)
556 		start = crashk_res.end;
557 	if (end > crashk_res.start && end < crashk_res.end)
558 		end = crashk_res.start;
559 #endif
560 
561 	if (start < end)
562 		add_active_range(nid, __pa(start) >> PAGE_SHIFT,
563 			__pa(end) >> PAGE_SHIFT);
564 	return 0;
565 }
566 
567 static int __init
568 count_reserved_pages (u64 start, u64 end, void *arg)
569 {
570 	unsigned long num_reserved = 0;
571 	unsigned long *count = arg;
572 
573 	for (; start < end; start += PAGE_SIZE)
574 		if (PageReserved(virt_to_page(start)))
575 			++num_reserved;
576 	*count += num_reserved;
577 	return 0;
578 }
579 
580 int
581 find_max_min_low_pfn (unsigned long start, unsigned long end, void *arg)
582 {
583 	unsigned long pfn_start, pfn_end;
584 #ifdef CONFIG_FLATMEM
585 	pfn_start = (PAGE_ALIGN(__pa(start))) >> PAGE_SHIFT;
586 	pfn_end = (PAGE_ALIGN(__pa(end - 1))) >> PAGE_SHIFT;
587 #else
588 	pfn_start = GRANULEROUNDDOWN(__pa(start)) >> PAGE_SHIFT;
589 	pfn_end = GRANULEROUNDUP(__pa(end - 1)) >> PAGE_SHIFT;
590 #endif
591 	min_low_pfn = min(min_low_pfn, pfn_start);
592 	max_low_pfn = max(max_low_pfn, pfn_end);
593 	return 0;
594 }
595 
596 /*
597  * Boot command-line option "nolwsys" can be used to disable the use of any light-weight
598  * system call handler.  When this option is in effect, all fsyscalls will end up bubbling
599  * down into the kernel and calling the normal (heavy-weight) syscall handler.  This is
600  * useful for performance testing, but conceivably could also come in handy for debugging
601  * purposes.
602  */
603 
604 static int nolwsys __initdata;
605 
606 static int __init
607 nolwsys_setup (char *s)
608 {
609 	nolwsys = 1;
610 	return 1;
611 }
612 
613 __setup("nolwsys", nolwsys_setup);
614 
615 void __init
616 mem_init (void)
617 {
618 	long reserved_pages, codesize, datasize, initsize;
619 	pg_data_t *pgdat;
620 	int i;
621 	static struct kcore_list kcore_mem, kcore_vmem, kcore_kernel;
622 
623 	BUG_ON(PTRS_PER_PGD * sizeof(pgd_t) != PAGE_SIZE);
624 	BUG_ON(PTRS_PER_PMD * sizeof(pmd_t) != PAGE_SIZE);
625 	BUG_ON(PTRS_PER_PTE * sizeof(pte_t) != PAGE_SIZE);
626 
627 #ifdef CONFIG_PCI
628 	/*
629 	 * This needs to be called _after_ the command line has been parsed but _before_
630 	 * any drivers that may need the PCI DMA interface are initialized or bootmem has
631 	 * been freed.
632 	 */
633 	platform_dma_init();
634 #endif
635 
636 #ifdef CONFIG_FLATMEM
637 	if (!mem_map)
638 		BUG();
639 	max_mapnr = max_low_pfn;
640 #endif
641 
642 	high_memory = __va(max_low_pfn * PAGE_SIZE);
643 
644 	kclist_add(&kcore_mem, __va(0), max_low_pfn * PAGE_SIZE);
645 	kclist_add(&kcore_vmem, (void *)VMALLOC_START, VMALLOC_END-VMALLOC_START);
646 	kclist_add(&kcore_kernel, _stext, _end - _stext);
647 
648 	for_each_online_pgdat(pgdat)
649 		if (pgdat->bdata->node_bootmem_map)
650 			totalram_pages += free_all_bootmem_node(pgdat);
651 
652 	reserved_pages = 0;
653 	efi_memmap_walk(count_reserved_pages, &reserved_pages);
654 
655 	codesize =  (unsigned long) _etext - (unsigned long) _stext;
656 	datasize =  (unsigned long) _edata - (unsigned long) _etext;
657 	initsize =  (unsigned long) __init_end - (unsigned long) __init_begin;
658 
659 	printk(KERN_INFO "Memory: %luk/%luk available (%luk code, %luk reserved, "
660 	       "%luk data, %luk init)\n", (unsigned long) nr_free_pages() << (PAGE_SHIFT - 10),
661 	       num_physpages << (PAGE_SHIFT - 10), codesize >> 10,
662 	       reserved_pages << (PAGE_SHIFT - 10), datasize >> 10, initsize >> 10);
663 
664 
665 	/*
666 	 * For fsyscall entrpoints with no light-weight handler, use the ordinary
667 	 * (heavy-weight) handler, but mark it by setting bit 0, so the fsyscall entry
668 	 * code can tell them apart.
669 	 */
670 	for (i = 0; i < NR_syscalls; ++i) {
671 		extern unsigned long fsyscall_table[NR_syscalls];
672 		extern unsigned long sys_call_table[NR_syscalls];
673 
674 		if (!fsyscall_table[i] || nolwsys)
675 			fsyscall_table[i] = sys_call_table[i] | 1;
676 	}
677 	setup_gate();
678 
679 #ifdef CONFIG_IA32_SUPPORT
680 	ia32_mem_init();
681 #endif
682 }
683 
684 #ifdef CONFIG_MEMORY_HOTPLUG
685 int arch_add_memory(int nid, u64 start, u64 size)
686 {
687 	pg_data_t *pgdat;
688 	struct zone *zone;
689 	unsigned long start_pfn = start >> PAGE_SHIFT;
690 	unsigned long nr_pages = size >> PAGE_SHIFT;
691 	int ret;
692 
693 	pgdat = NODE_DATA(nid);
694 
695 	zone = pgdat->node_zones + ZONE_NORMAL;
696 	ret = __add_pages(zone, start_pfn, nr_pages);
697 
698 	if (ret)
699 		printk("%s: Problem encountered in __add_pages() as ret=%d\n",
700 		       __func__,  ret);
701 
702 	return ret;
703 }
704 #ifdef CONFIG_MEMORY_HOTREMOVE
705 int remove_memory(u64 start, u64 size)
706 {
707 	unsigned long start_pfn, end_pfn;
708 	unsigned long timeout = 120 * HZ;
709 	int ret;
710 	start_pfn = start >> PAGE_SHIFT;
711 	end_pfn = start_pfn + (size >> PAGE_SHIFT);
712 	ret = offline_pages(start_pfn, end_pfn, timeout);
713 	if (ret)
714 		goto out;
715 	/* we can free mem_map at this point */
716 out:
717 	return ret;
718 }
719 EXPORT_SYMBOL_GPL(remove_memory);
720 #endif /* CONFIG_MEMORY_HOTREMOVE */
721 #endif
722 
723 /*
724  * Even when CONFIG_IA32_SUPPORT is not enabled it is
725  * useful to have the Linux/x86 domain registered to
726  * avoid an attempted module load when emulators call
727  * personality(PER_LINUX32). This saves several milliseconds
728  * on each such call.
729  */
730 static struct exec_domain ia32_exec_domain;
731 
732 static int __init
733 per_linux32_init(void)
734 {
735 	ia32_exec_domain.name = "Linux/x86";
736 	ia32_exec_domain.handler = NULL;
737 	ia32_exec_domain.pers_low = PER_LINUX32;
738 	ia32_exec_domain.pers_high = PER_LINUX32;
739 	ia32_exec_domain.signal_map = default_exec_domain.signal_map;
740 	ia32_exec_domain.signal_invmap = default_exec_domain.signal_invmap;
741 	register_exec_domain(&ia32_exec_domain);
742 
743 	return 0;
744 }
745 
746 __initcall(per_linux32_init);
747