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