[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / x86 / mm / init.c

#include <linux/gfp.h>
#include <linux/initrd.h>
#include <linux/ioport.h>
#include <linux/swap.h>
#include <linux/memblock.h>

#include <asm/cacheflush.h>
#include <asm/e820.h>
#include <asm/init.h>
#include <asm/page.h>
#include <asm/page_types.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/system.h>
#include <asm/tlbflush.h>
#include <asm/tlb.h>
#include <asm/proto.h>

DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

unsigned long __initdata pgt_buf_start;
unsigned long __meminitdata pgt_buf_end;
unsigned long __meminitdata pgt_buf_top;

int after_bootmem;

int direct_gbpages
#ifdef CONFIG_DIRECT_GBPAGES
				= 1
#endif
;

static void __init find_early_table_space(unsigned long end, int use_pse,
					  int use_gbpages)
{
	unsigned long puds, pmds, ptes, tables, start = 0, good_end = end;
	phys_addr_t base;

	puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
	tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);

	if (use_gbpages) {
		unsigned long extra;

		extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
		pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
	} else
		pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;

	tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);

	if (use_pse) {
		unsigned long extra;

		extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
#ifdef CONFIG_X86_32
		extra += PMD_SIZE;
#endif
		ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
	} else
		ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;

	tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);

#ifdef CONFIG_X86_32
	/* for fixmap */
	tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);

	good_end = max_pfn_mapped << PAGE_SHIFT;
#endif

	base = memblock_find_in_range(start, good_end, tables, PAGE_SIZE);
	if (base == MEMBLOCK_ERROR)
		panic("Cannot find space for the kernel page tables");

	pgt_buf_start = base >> PAGE_SHIFT;
	pgt_buf_end = pgt_buf_start;
	pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT);

	printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
		end, pgt_buf_start << PAGE_SHIFT, pgt_buf_top << PAGE_SHIFT);
}

void __init native_pagetable_reserve(u64 start, u64 end)
{
	memblock_x86_reserve_range(start, end, "PGTABLE");
}

struct map_range {
	unsigned long start;
	unsigned long end;
	unsigned page_size_mask;
};

#ifdef CONFIG_X86_32
#define NR_RANGE_MR 3
#else /* CONFIG_X86_64 */
#define NR_RANGE_MR 5
#endif

static int __meminit save_mr(struct map_range *mr, int nr_range,
			     unsigned long start_pfn, unsigned long end_pfn,
			     unsigned long page_size_mask)
{
	if (start_pfn < end_pfn) {
		if (nr_range >= NR_RANGE_MR)
			panic("run out of range for init_memory_mapping\n");
		mr[nr_range].start = start_pfn<<PAGE_SHIFT;
		mr[nr_range].end   = end_pfn<<PAGE_SHIFT;
		mr[nr_range].page_size_mask = page_size_mask;
		nr_range++;
	}

	return nr_range;
}

/*
 * Setup the direct mapping of the physical memory at PAGE_OFFSET.
 * This runs before bootmem is initialized and gets pages directly from
 * the physical memory. To access them they are temporarily mapped.
 */
unsigned long __init_refok init_memory_mapping(unsigned long start,
					       unsigned long end)
{
	unsigned long page_size_mask = 0;
	unsigned long start_pfn, end_pfn;
	unsigned long ret = 0;
	unsigned long pos;

	struct map_range mr[NR_RANGE_MR];
	int nr_range, i;
	int use_pse, use_gbpages;

	printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end);

#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KMEMCHECK)
	/*
	 * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
	 * This will simplify cpa(), which otherwise needs to support splitting
	 * large pages into small in interrupt context, etc.
	 */
	use_pse = use_gbpages = 0;
#else
	use_pse = cpu_has_pse;
	use_gbpages = direct_gbpages;
#endif

	/* Enable PSE if available */
	if (cpu_has_pse)
		set_in_cr4(X86_CR4_PSE);

	/* Enable PGE if available */
	if (cpu_has_pge) {
		set_in_cr4(X86_CR4_PGE);
		__supported_pte_mask |= _PAGE_GLOBAL;
	}

	if (use_gbpages)
		page_size_mask |= 1 << PG_LEVEL_1G;
	if (use_pse)
		page_size_mask |= 1 << PG_LEVEL_2M;

	memset(mr, 0, sizeof(mr));
	nr_range = 0;

	/* head if not big page alignment ? */
	start_pfn = start >> PAGE_SHIFT;
	pos = start_pfn << PAGE_SHIFT;
#ifdef CONFIG_X86_32
	/*
	 * Don't use a large page for the first 2/4MB of memory
	 * because there are often fixed size MTRRs in there
	 * and overlapping MTRRs into large pages can cause
	 * slowdowns.
	 */
	if (pos == 0)
		end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT);
	else
		end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
				 << (PMD_SHIFT - PAGE_SHIFT);
#else /* CONFIG_X86_64 */
	end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT)
			<< (PMD_SHIFT - PAGE_SHIFT);
#endif
	if (end_pfn > (end >> PAGE_SHIFT))
		end_pfn = end >> PAGE_SHIFT;
	if (start_pfn < end_pfn) {
		nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
		pos = end_pfn << PAGE_SHIFT;
	}

	/* big page (2M) range */
	start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
			 << (PMD_SHIFT - PAGE_SHIFT);
#ifdef CONFIG_X86_32
	end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
#else /* CONFIG_X86_64 */
	end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
			 << (PUD_SHIFT - PAGE_SHIFT);
	if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)))
		end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT));
#endif

	if (start_pfn < end_pfn) {
		nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
				page_size_mask & (1<<PG_LEVEL_2M));
		pos = end_pfn << PAGE_SHIFT;
	}

#ifdef CONFIG_X86_64
	/* big page (1G) range */
	start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
			 << (PUD_SHIFT - PAGE_SHIFT);
	end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
	if (start_pfn < end_pfn) {
		nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
				page_size_mask &
				 ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
		pos = end_pfn << PAGE_SHIFT;
	}

	/* tail is not big page (1G) alignment */
	start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
			 << (PMD_SHIFT - PAGE_SHIFT);
	end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
	if (start_pfn < end_pfn) {
		nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
				page_size_mask & (1<<PG_LEVEL_2M));
		pos = end_pfn << PAGE_SHIFT;
	}
#endif

	/* tail is not big page (2M) alignment */
	start_pfn = pos>>PAGE_SHIFT;
	end_pfn = end>>PAGE_SHIFT;
	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);

	/* try to merge same page size and continuous */
	for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
		unsigned long old_start;
		if (mr[i].end != mr[i+1].start ||
		    mr[i].page_size_mask != mr[i+1].page_size_mask)
			continue;
		/* move it */
		old_start = mr[i].start;
		memmove(&mr[i], &mr[i+1],
			(nr_range - 1 - i) * sizeof(struct map_range));
		mr[i--].start = old_start;
		nr_range--;
	}

	for (i = 0; i < nr_range; i++)
		printk(KERN_DEBUG " %010lx - %010lx page %s\n",
				mr[i].start, mr[i].end,
			(mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
			 (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));

	/*
	 * Find space for the kernel direct mapping tables.
	 *
	 * Later we should allocate these tables in the local node of the
	 * memory mapped. Unfortunately this is done currently before the
	 * nodes are discovered.
	 */
	if (!after_bootmem)
		find_early_table_space(end, use_pse, use_gbpages);

	for (i = 0; i < nr_range; i++)
		ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
						   mr[i].page_size_mask);

#ifdef CONFIG_X86_32
	early_ioremap_page_table_range_init();

	load_cr3(swapper_pg_dir);
#endif

	__flush_tlb_all();

	/*
	 * Reserve the kernel pagetable pages we used (pgt_buf_start -
	 * pgt_buf_end) and free the other ones (pgt_buf_end - pgt_buf_top)
	 * so that they can be reused for other purposes.
	 *
	 * On native it just means calling memblock_x86_reserve_range, on Xen it
	 * also means marking RW the pagetable pages that we allocated before
	 * but that haven't been used.
	 *
	 * In fact on xen we mark RO the whole range pgt_buf_start -
	 * pgt_buf_top, because we have to make sure that when
	 * init_memory_mapping reaches the pagetable pages area, it maps
	 * RO all the pagetable pages, including the ones that are beyond
	 * pgt_buf_end at that time.
	 */
	if (!after_bootmem && pgt_buf_end > pgt_buf_start)
		x86_init.mapping.pagetable_reserve(PFN_PHYS(pgt_buf_start),
				PFN_PHYS(pgt_buf_end));

	if (!after_bootmem)
		early_memtest(start, end);

	return ret >> PAGE_SHIFT;
}


/*
 * devmem_is_allowed() checks to see if /dev/mem access to a certain address
 * is valid. The argument is a physical page number.
 *
 *
 * On x86, access has to be given to the first megabyte of ram because that area
 * contains bios code and data regions used by X and dosemu and similar apps.
 * Access has to be given to non-kernel-ram areas as well, these contain the PCI
 * mmio resources as well as potential bios/acpi data regions.
 */
int devmem_is_allowed(unsigned long pagenr)
{
	if (pagenr <= 256)
		return 1;
	if (iomem_is_exclusive(pagenr << PAGE_SHIFT))
		return 0;
	if (!page_is_ram(pagenr))
		return 1;
	return 0;
}

void free_init_pages(char *what, unsigned long begin, unsigned long end)
{
	unsigned long addr;
	unsigned long begin_aligned, end_aligned;

	/* Make sure boundaries are page aligned */
	begin_aligned = PAGE_ALIGN(begin);
	end_aligned   = end & PAGE_MASK;

	if (WARN_ON(begin_aligned != begin || end_aligned != end)) {
		begin = begin_aligned;
		end   = end_aligned;
	}

	if (begin >= end)
		return;

	addr = begin;

	/*
	 * If debugging page accesses then do not free this memory but
	 * mark them not present - any buggy init-section access will
	 * create a kernel page fault:
	 */
#ifdef CONFIG_DEBUG_PAGEALLOC
	printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
		begin, end);
	set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
#else
	/*
	 * We just marked the kernel text read only above, now that
	 * we are going to free part of that, we need to make that
	 * writeable and non-executable first.
	 */
	set_memory_nx(begin, (end - begin) >> PAGE_SHIFT);
	set_memory_rw(begin, (end - begin) >> PAGE_SHIFT);

	printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);

	for (; addr < end; addr += PAGE_SIZE) {
		ClearPageReserved(virt_to_page(addr));
		init_page_count(virt_to_page(addr));
		memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
		free_page(addr);
		totalram_pages++;
	}
#endif
}

void free_initmem(void)
{
	free_init_pages("unused kernel memory",
			(unsigned long)(&__init_begin),
			(unsigned long)(&__init_end));
}

#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
	/*
	 * end could be not aligned, and We can not align that,
	 * decompresser could be confused by aligned initrd_end
	 * We already reserve the end partial page before in
	 *   - i386_start_kernel()
	 *   - x86_64_start_kernel()
	 *   - relocate_initrd()
	 * So here We can do PAGE_ALIGN() safely to get partial page to be freed
	 */
	free_init_pages("initrd memory", start, PAGE_ALIGN(end));
}
#endif
Commit	Line	Data
5a0e3ad6	1	#include <linux/gfp.h>
2c1b284e	2	#include <linux/initrd.h>
540aca06	3	#include <linux/ioport.h>
e5b2bb55	4	#include <linux/swap.h>
a9ce6bc1	5	#include <linux/memblock.h>
540aca06	6
e5b2bb55	7	#include <asm/cacheflush.h>
f765090a	8	#include <asm/e820.h>
4fcb2083	9	#include <asm/init.h>
e5b2bb55	10	#include <asm/page.h>
540aca06	11	#include <asm/page_types.h>
e5b2bb55	12	#include <asm/sections.h>
49834396	13	#include <asm/setup.h>
e5b2bb55	14	#include <asm/system.h>
f765090a	15	#include <asm/tlbflush.h>
9518e0e4	16	#include <asm/tlb.h>
76c06927	17	#include <asm/proto.h>
9518e0e4 PE	18
9518e0e4 PE	19	DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
f765090a	20
d1b19426 YL	21	unsigned long __initdata pgt_buf_start;
	22	unsigned long __meminitdata pgt_buf_end;
	23	unsigned long __meminitdata pgt_buf_top;
f765090a PE	24
	25	int after_bootmem;
	26
	27	int direct_gbpages
	28	#ifdef CONFIG_DIRECT_GBPAGES
	29	= 1
	30	#endif
	31	;
	32
	33	static void __init find_early_table_space(unsigned long end, int use_pse,
	34	int use_gbpages)
	35	{
4b239f45	36	unsigned long puds, pmds, ptes, tables, start = 0, good_end = end;
a9ce6bc1	37	phys_addr_t base;
f765090a PE	38
	39	puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
	40	tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
	41
	42	if (use_gbpages) {
	43	unsigned long extra;
	44
	45	extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
	46	pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
	47	} else
	48	pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
	49
	50	tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
	51
	52	if (use_pse) {
	53	unsigned long extra;
	54
	55	extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
	56	#ifdef CONFIG_X86_32
	57	extra += PMD_SIZE;
	58	#endif
	59	ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
	60	} else
	61	ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
	62
	63	tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
	64
	65	#ifdef CONFIG_X86_32
	66	/* for fixmap */
	67	tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
f765090a	68
4b239f45	69	good_end = max_pfn_mapped << PAGE_SHIFT;
f765090a	70	#endif
1411e0ec	71
4b239f45	72	base = memblock_find_in_range(start, good_end, tables, PAGE_SIZE);
a9ce6bc1	73	if (base == MEMBLOCK_ERROR)
f765090a PE	74	panic("Cannot find space for the kernel page tables");
f765090a PE	75
d1b19426 YL	76	pgt_buf_start = base >> PAGE_SHIFT;
	77	pgt_buf_end = pgt_buf_start;
	78	pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT);
f765090a PE	79
f765090a PE	80	printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
d1b19426	81	end, pgt_buf_start << PAGE_SHIFT, pgt_buf_top << PAGE_SHIFT);
f765090a PE	82	}
f765090a PE	83
53f8023f	84	void __init native_pagetable_reserve(u64 start, u64 end)
279b706b SS	85	{
	86	memblock_x86_reserve_range(start, end, "PGTABLE");
	87	}
	88
f765090a PE	89	struct map_range {
	90	unsigned long start;
	91	unsigned long end;
	92	unsigned page_size_mask;
	93	};
	94
	95	#ifdef CONFIG_X86_32
	96	#define NR_RANGE_MR 3
	97	#else /* CONFIG_X86_64 */
	98	#define NR_RANGE_MR 5
	99	#endif
	100
dc9dd5cc JB	101	static int __meminit save_mr(struct map_range *mr, int nr_range,
	102	unsigned long start_pfn, unsigned long end_pfn,
	103	unsigned long page_size_mask)
f765090a PE	104	{
	105	if (start_pfn < end_pfn) {
	106	if (nr_range >= NR_RANGE_MR)
	107	panic("run out of range for init_memory_mapping\n");
	108	mr[nr_range].start = start_pfn<<PAGE_SHIFT;
	109	mr[nr_range].end = end_pfn<<PAGE_SHIFT;
	110	mr[nr_range].page_size_mask = page_size_mask;
	111	nr_range++;
	112	}
	113
	114	return nr_range;
	115	}
	116
f765090a PE	117	/*
	118	* Setup the direct mapping of the physical memory at PAGE_OFFSET.
	119	* This runs before bootmem is initialized and gets pages directly from
	120	* the physical memory. To access them they are temporarily mapped.
	121	*/
	122	unsigned long __init_refok init_memory_mapping(unsigned long start,
	123	unsigned long end)
	124	{
	125	unsigned long page_size_mask = 0;
	126	unsigned long start_pfn, end_pfn;
c77a3b59	127	unsigned long ret = 0;
f765090a	128	unsigned long pos;
f765090a PE	129
	130	struct map_range mr[NR_RANGE_MR];
	131	int nr_range, i;
	132	int use_pse, use_gbpages;
	133
	134	printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end);
	135
f8561296	136	#if defined(CONFIG_DEBUG_PAGEALLOC) \|\| defined(CONFIG_KMEMCHECK)
f765090a PE	137	/*
	138	* For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
	139	* This will simplify cpa(), which otherwise needs to support splitting
	140	* large pages into small in interrupt context, etc.
	141	*/
	142	use_pse = use_gbpages = 0;
	143	#else
	144	use_pse = cpu_has_pse;
	145	use_gbpages = direct_gbpages;
	146	#endif
	147
f765090a PE	148	/* Enable PSE if available */
	149	if (cpu_has_pse)
	150	set_in_cr4(X86_CR4_PSE);
	151
	152	/* Enable PGE if available */
	153	if (cpu_has_pge) {
	154	set_in_cr4(X86_CR4_PGE);
	155	__supported_pte_mask \|= _PAGE_GLOBAL;
	156	}
f765090a PE	157
	158	if (use_gbpages)
	159	page_size_mask \|= 1 << PG_LEVEL_1G;
	160	if (use_pse)
	161	page_size_mask \|= 1 << PG_LEVEL_2M;
	162
	163	memset(mr, 0, sizeof(mr));
	164	nr_range = 0;
	165
	166	/* head if not big page alignment ? */
	167	start_pfn = start >> PAGE_SHIFT;
	168	pos = start_pfn << PAGE_SHIFT;
	169	#ifdef CONFIG_X86_32
	170	/*
	171	* Don't use a large page for the first 2/4MB of memory
	172	* because there are often fixed size MTRRs in there
	173	* and overlapping MTRRs into large pages can cause
	174	* slowdowns.
	175	*/
	176	if (pos == 0)
	177	end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT);
	178	else
	179	end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
	180	<< (PMD_SHIFT - PAGE_SHIFT);
	181	#else /* CONFIG_X86_64 */
	182	end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT)
	183	<< (PMD_SHIFT - PAGE_SHIFT);
	184	#endif
	185	if (end_pfn > (end >> PAGE_SHIFT))
	186	end_pfn = end >> PAGE_SHIFT;
	187	if (start_pfn < end_pfn) {
	188	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
	189	pos = end_pfn << PAGE_SHIFT;
	190	}
	191
	192	/* big page (2M) range */
	193	start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
	194	<< (PMD_SHIFT - PAGE_SHIFT);
	195	#ifdef CONFIG_X86_32
	196	end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
	197	#else /* CONFIG_X86_64 */
	198	end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
	199	<< (PUD_SHIFT - PAGE_SHIFT);
	200	if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)))
	201	end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT));
	202	#endif
	203
	204	if (start_pfn < end_pfn) {
	205	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
	206	page_size_mask & (1<<PG_LEVEL_2M));
	207	pos = end_pfn << PAGE_SHIFT;
	208	}
	209
	210	#ifdef CONFIG_X86_64
	211	/* big page (1G) range */
	212	start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
	213	<< (PUD_SHIFT - PAGE_SHIFT);
	214	end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
	215	if (start_pfn < end_pfn) {
	216	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
	217	page_size_mask &
	218	((1<<PG_LEVEL_2M)\|(1<<PG_LEVEL_1G)));
	219	pos = end_pfn << PAGE_SHIFT;
	220	}
221
222	/* tail is not big page (1G) alignment */
223	start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
224	<< (PMD_SHIFT - PAGE_SHIFT);
225	end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
226	if (start_pfn < end_pfn) {
227	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
228	page_size_mask & (1<<PG_LEVEL_2M));
229	pos = end_pfn << PAGE_SHIFT;
230	}
231	#endif
232
233	/* tail is not big page (2M) alignment */
234	start_pfn = pos>>PAGE_SHIFT;
235	end_pfn = end>>PAGE_SHIFT;
236	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
237
238	/* try to merge same page size and continuous */
239	for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
240	unsigned long old_start;
241	if (mr[i].end != mr[i+1].start \|\|
242	mr[i].page_size_mask != mr[i+1].page_size_mask)
243	continue;
244	/* move it */
245	old_start = mr[i].start;
246	memmove(&mr[i], &mr[i+1],
247	(nr_range - 1 - i) * sizeof(struct map_range));
248	mr[i--].start = old_start;
249	nr_range--;
250	}
251
252	for (i = 0; i < nr_range; i++)
253	printk(KERN_DEBUG " %010lx - %010lx page %s\n",
254	mr[i].start, mr[i].end,
255	(mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
256	(mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
257
258	/*
259	* Find space for the kernel direct mapping tables.
260	*
261	* Later we should allocate these tables in the local node of the
262	* memory mapped. Unfortunately this is done currently before the
263	* nodes are discovered.
264	*/
265	if (!after_bootmem)
266	find_early_table_space(end, use_pse, use_gbpages);
267
f765090a PE	268	for (i = 0; i < nr_range; i++)
	269	ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
	270	mr[i].page_size_mask);
f765090a PE	271
	272	#ifdef CONFIG_X86_32
	273	early_ioremap_page_table_range_init();
	274
	275	load_cr3(swapper_pg_dir);
	276	#endif
	277
f765090a PE	278	__flush_tlb_all();
f765090a PE	279
279b706b SS	280	/*
	281	* Reserve the kernel pagetable pages we used (pgt_buf_start -
	282	* pgt_buf_end) and free the other ones (pgt_buf_end - pgt_buf_top)
	283	* so that they can be reused for other purposes.
	284	*
	285	* On native it just means calling memblock_x86_reserve_range, on Xen it
	286	* also means marking RW the pagetable pages that we allocated before
	287	* but that haven't been used.
	288	*
	289	* In fact on xen we mark RO the whole range pgt_buf_start -
	290	* pgt_buf_top, because we have to make sure that when
	291	* init_memory_mapping reaches the pagetable pages area, it maps
	292	* RO all the pagetable pages, including the ones that are beyond
	293	* pgt_buf_end at that time.
	294	*/
d1b19426	295	if (!after_bootmem && pgt_buf_end > pgt_buf_start)
279b706b SS	296	x86_init.mapping.pagetable_reserve(PFN_PHYS(pgt_buf_start),
279b706b SS	297	PFN_PHYS(pgt_buf_end));
f765090a PE	298
	299	if (!after_bootmem)
	300	early_memtest(start, end);
	301
	302	return ret >> PAGE_SHIFT;
	303	}
	304
e5b2bb55	305
540aca06 PE	306	/*
	307	* devmem_is_allowed() checks to see if /dev/mem access to a certain address
	308	* is valid. The argument is a physical page number.
	309	*
	310	*
	311	* On x86, access has to be given to the first megabyte of ram because that area
	312	* contains bios code and data regions used by X and dosemu and similar apps.
	313	* Access has to be given to non-kernel-ram areas as well, these contain the PCI
	314	* mmio resources as well as potential bios/acpi data regions.
	315	*/
	316	int devmem_is_allowed(unsigned long pagenr)
	317	{
	318	if (pagenr <= 256)
	319	return 1;
	320	if (iomem_is_exclusive(pagenr << PAGE_SHIFT))
	321	return 0;
	322	if (!page_is_ram(pagenr))
	323	return 1;
	324	return 0;
	325	}
	326
e5b2bb55 PE	327	void free_init_pages(char *what, unsigned long begin, unsigned long end)
e5b2bb55 PE	328	{
c967da6a YL	329	unsigned long addr;
c967da6a YL	330	unsigned long begin_aligned, end_aligned;
e5b2bb55	331
c967da6a YL	332	/* Make sure boundaries are page aligned */
	333	begin_aligned = PAGE_ALIGN(begin);
	334	end_aligned = end & PAGE_MASK;
	335
	336	if (WARN_ON(begin_aligned != begin \|\| end_aligned != end)) {
	337	begin = begin_aligned;
	338	end = end_aligned;
	339	}
	340
	341	if (begin >= end)
e5b2bb55 PE	342	return;
e5b2bb55 PE	343
c967da6a YL	344	addr = begin;
c967da6a YL	345
e5b2bb55 PE	346	/*
	347	* If debugging page accesses then do not free this memory but
	348	* mark them not present - any buggy init-section access will
	349	* create a kernel page fault:
	350	*/
	351	#ifdef CONFIG_DEBUG_PAGEALLOC
	352	printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
c967da6a	353	begin, end);
e5b2bb55 PE	354	set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
	355	#else
	356	/*
	357	* We just marked the kernel text read only above, now that
	358	* we are going to free part of that, we need to make that
5bd5a452	359	* writeable and non-executable first.
e5b2bb55	360	*/
5bd5a452	361	set_memory_nx(begin, (end - begin) >> PAGE_SHIFT);
e5b2bb55 PE	362	set_memory_rw(begin, (end - begin) >> PAGE_SHIFT);
	363
	364	printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
	365
	366	for (; addr < end; addr += PAGE_SIZE) {
	367	ClearPageReserved(virt_to_page(addr));
	368	init_page_count(virt_to_page(addr));
c967da6a	369	memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
e5b2bb55 PE	370	free_page(addr);
	371	totalram_pages++;
	372	}
	373	#endif
	374	}
	375
	376	void free_initmem(void)
	377	{
	378	free_init_pages("unused kernel memory",
	379	(unsigned long)(&__init_begin),
	380	(unsigned long)(&__init_end));
	381	}
731ddea6 PE	382
	383	#ifdef CONFIG_BLK_DEV_INITRD
	384	void free_initrd_mem(unsigned long start, unsigned long end)
	385	{
c967da6a YL	386	/*
	387	* end could be not aligned, and We can not align that,
	388	* decompresser could be confused by aligned initrd_end
	389	* We already reserve the end partial page before in
	390	* - i386_start_kernel()
	391	* - x86_64_start_kernel()
	392	* - relocate_initrd()
	393	* So here We can do PAGE_ALIGN() safely to get partial page to be freed
	394	*/
	395	free_init_pages("initrd memory", start, PAGE_ALIGN(end));
731ddea6 PE	396	}
731ddea6 PE	397	#endif