[deliverable/linux.git] / arch / x86 / mm / init.c

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

DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

unsigned long __initdata e820_table_start;
unsigned long __meminitdata e820_table_end;
unsigned long __meminitdata e820_table_top;

int after_bootmem;

int direct_gbpages
#ifdef CONFIG_DIRECT_GBPAGES
				= 1
#endif
;

int nx_enabled;

#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
static int disable_nx __cpuinitdata;

/*
 * noexec = on|off
 *
 * Control non-executable mappings for processes.
 *
 * on      Enable
 * off     Disable
 */
static int __init noexec_setup(char *str)
{
	if (!str)
		return -EINVAL;
	if (!strncmp(str, "on", 2)) {
		__supported_pte_mask |= _PAGE_NX;
		disable_nx = 0;
	} else if (!strncmp(str, "off", 3)) {
		disable_nx = 1;
		__supported_pte_mask &= ~_PAGE_NX;
	}
	return 0;
}
early_param("noexec", noexec_setup);
#endif

#ifdef CONFIG_X86_PAE
static void __init set_nx(void)
{
	unsigned int v[4], l, h;

	if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) {
		cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]);

		if ((v[3] & (1 << 20)) && !disable_nx) {
			rdmsr(MSR_EFER, l, h);
			l |= EFER_NX;
			wrmsr(MSR_EFER, l, h);
			nx_enabled = 1;
			__supported_pte_mask |= _PAGE_NX;
		}
	}
}
#else
static inline void set_nx(void)
{
}
#endif

#ifdef CONFIG_X86_64
void __cpuinit check_efer(void)
{
	unsigned long efer;

	rdmsrl(MSR_EFER, efer);
	if (!(efer & EFER_NX) || disable_nx)
		__supported_pte_mask &= ~_PAGE_NX;
}
#endif

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

	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);
#endif

	/*
	 * RED-PEN putting page tables only on node 0 could
	 * cause a hotspot and fill up ZONE_DMA. The page tables
	 * need roughly 0.5KB per GB.
	 */
#ifdef CONFIG_X86_32
	start = 0x7000;
#else
	start = 0x8000;
#endif
	e820_table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT,
					tables, PAGE_SIZE);
	if (e820_table_start == -1UL)
		panic("Cannot find space for the kernel page tables");

	e820_table_start >>= PAGE_SHIFT;
	e820_table_end = e820_table_start;
	e820_table_top = e820_table_start + (tables >> PAGE_SHIFT);

	printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
		end, e820_table_start << PAGE_SHIFT, e820_table_top << PAGE_SHIFT);
}

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;
}

#ifdef CONFIG_X86_64
static void __init init_gbpages(void)
{
	if (direct_gbpages && cpu_has_gbpages)
		printk(KERN_INFO "Using GB pages for direct mapping\n");
	else
		direct_gbpages = 0;
}
#else
static inline void init_gbpages(void)
{
}
#endif

/*
 * 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 (!after_bootmem)
		init_gbpages();

#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

	set_nx();
	if (nx_enabled)
		printk(KERN_INFO "NX (Execute Disable) protection: active\n");

	/* 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);

#ifdef CONFIG_X86_32
	for (i = 0; i < nr_range; i++)
		kernel_physical_mapping_init(mr[i].start, mr[i].end,
					     mr[i].page_size_mask);
	ret = end;
#else /* CONFIG_X86_64 */
	for (i = 0; i < nr_range; i++)
		ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
						   mr[i].page_size_mask);
#endif

#ifdef CONFIG_X86_32
	early_ioremap_page_table_range_init();

	load_cr3(swapper_pg_dir);
#endif

#ifdef CONFIG_X86_64
	if (!after_bootmem && !start) {
		pud_t *pud;
		pmd_t *pmd;

		mmu_cr4_features = read_cr4();

		/*
		 * _brk_end cannot change anymore, but it and _end may be
		 * located on different 2M pages. cleanup_highmap(), however,
		 * can only consider _end when it runs, so destroy any
		 * mappings beyond _brk_end here.
		 */
		pud = pud_offset(pgd_offset_k(_brk_end), _brk_end);
		pmd = pmd_offset(pud, _brk_end - 1);
		while (++pmd <= pmd_offset(pud, (unsigned long)_end - 1))
			pmd_clear(pmd);
	}
#endif
	__flush_tlb_all();

	if (!after_bootmem && e820_table_end > e820_table_start)
		reserve_early(e820_table_start << PAGE_SHIFT,
				 e820_table_end << PAGE_SHIFT, "PGTABLE");

	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 = begin;

	if (addr >= end)
		return;

	/*
	 * 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, PAGE_ALIGN(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 first.
	 */
	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 & ~(PAGE_SIZE-1)),
			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)
{
	free_init_pages("initrd memory", start, end);
}
#endif
Commit	Line	Data
2c1b284e	1	#include <linux/initrd.h>
540aca06	2	#include <linux/ioport.h>
e5b2bb55	3	#include <linux/swap.h>
540aca06	4
e5b2bb55	5	#include <asm/cacheflush.h>
f765090a	6	#include <asm/e820.h>
4fcb2083	7	#include <asm/init.h>
e5b2bb55	8	#include <asm/page.h>
540aca06	9	#include <asm/page_types.h>
e5b2bb55	10	#include <asm/sections.h>
49834396	11	#include <asm/setup.h>
e5b2bb55	12	#include <asm/system.h>
f765090a	13	#include <asm/tlbflush.h>
9518e0e4 PE	14	#include <asm/tlb.h>
	15
	16	DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
f765090a	17
298af9d8 PE	18	unsigned long __initdata e820_table_start;
	19	unsigned long __meminitdata e820_table_end;
	20	unsigned long __meminitdata e820_table_top;
f765090a PE	21
	22	int after_bootmem;
	23
	24	int direct_gbpages
	25	#ifdef CONFIG_DIRECT_GBPAGES
	26	= 1
	27	#endif
	28	;
	29
89388913 PE	30	int nx_enabled;
	31
	32	#if defined(CONFIG_X86_64) \|\| defined(CONFIG_X86_PAE)
	33	static int disable_nx __cpuinitdata;
	34
	35	/*
	36	* noexec = on\|off
	37	*
	38	* Control non-executable mappings for processes.
	39	*
	40	* on Enable
	41	* off Disable
	42	*/
	43	static int __init noexec_setup(char *str)
	44	{
	45	if (!str)
	46	return -EINVAL;
	47	if (!strncmp(str, "on", 2)) {
	48	__supported_pte_mask \|= _PAGE_NX;
	49	disable_nx = 0;
	50	} else if (!strncmp(str, "off", 3)) {
	51	disable_nx = 1;
	52	__supported_pte_mask &= ~_PAGE_NX;
	53	}
	54	return 0;
	55	}
	56	early_param("noexec", noexec_setup);
	57	#endif
	58
	59	#ifdef CONFIG_X86_PAE
	60	static void __init set_nx(void)
	61	{
	62	unsigned int v[4], l, h;
	63
	64	if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) {
	65	cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]);
	66
	67	if ((v[3] & (1 << 20)) && !disable_nx) {
	68	rdmsr(MSR_EFER, l, h);
	69	l \|= EFER_NX;
	70	wrmsr(MSR_EFER, l, h);
	71	nx_enabled = 1;
	72	__supported_pte_mask \|= _PAGE_NX;
	73	}
	74	}
	75	}
	76	#else
	77	static inline void set_nx(void)
	78	{
	79	}
	80	#endif
	81
	82	#ifdef CONFIG_X86_64
	83	void __cpuinit check_efer(void)
	84	{
	85	unsigned long efer;
	86
	87	rdmsrl(MSR_EFER, efer);
	88	if (!(efer & EFER_NX) \|\| disable_nx)
	89	__supported_pte_mask &= ~_PAGE_NX;
	90	}
	91	#endif
	92
f765090a PE	93	static void __init find_early_table_space(unsigned long end, int use_pse,
	94	int use_gbpages)
	95	{
	96	unsigned long puds, pmds, ptes, tables, start;
	97
	98	puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
	99	tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
	100
	101	if (use_gbpages) {
	102	unsigned long extra;
	103
	104	extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT);
	105	pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT;
	106	} else
	107	pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
	108
	109	tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
	110
	111	if (use_pse) {
	112	unsigned long extra;
	113
	114	extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
	115	#ifdef CONFIG_X86_32
	116	extra += PMD_SIZE;
	117	#endif
	118	ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
	119	} else
	120	ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
	121
	122	tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
	123
	124	#ifdef CONFIG_X86_32
	125	/* for fixmap */
	126	tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
	127	#endif
	128
	129	/*
	130	* RED-PEN putting page tables only on node 0 could
	131	* cause a hotspot and fill up ZONE_DMA. The page tables
	132	* need roughly 0.5KB per GB.
	133	*/
	134	#ifdef CONFIG_X86_32
	135	start = 0x7000;
80989ce0	136	#else
f765090a	137	start = 0x8000;
f765090a	138	#endif
80989ce0 YL	139	e820_table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT,
80989ce0 YL	140	tables, PAGE_SIZE);
298af9d8	141	if (e820_table_start == -1UL)
f765090a PE	142	panic("Cannot find space for the kernel page tables");
f765090a PE	143
298af9d8 PE	144	e820_table_start >>= PAGE_SHIFT;
	145	e820_table_end = e820_table_start;
	146	e820_table_top = e820_table_start + (tables >> PAGE_SHIFT);
f765090a PE	147
f765090a PE	148	printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n",
298af9d8	149	end, e820_table_start << PAGE_SHIFT, e820_table_top << PAGE_SHIFT);
f765090a PE	150	}
	151
	152	struct map_range {
	153	unsigned long start;
	154	unsigned long end;
	155	unsigned page_size_mask;
	156	};
	157
	158	#ifdef CONFIG_X86_32
	159	#define NR_RANGE_MR 3
	160	#else /* CONFIG_X86_64 */
	161	#define NR_RANGE_MR 5
	162	#endif
	163
dc9dd5cc JB	164	static int __meminit save_mr(struct map_range *mr, int nr_range,
	165	unsigned long start_pfn, unsigned long end_pfn,
	166	unsigned long page_size_mask)
f765090a PE	167	{
	168	if (start_pfn < end_pfn) {
	169	if (nr_range >= NR_RANGE_MR)
	170	panic("run out of range for init_memory_mapping\n");
	171	mr[nr_range].start = start_pfn<<PAGE_SHIFT;
	172	mr[nr_range].end = end_pfn<<PAGE_SHIFT;
	173	mr[nr_range].page_size_mask = page_size_mask;
	174	nr_range++;
	175	}
	176
	177	return nr_range;
	178	}
	179
	180	#ifdef CONFIG_X86_64
	181	static void __init init_gbpages(void)
	182	{
	183	if (direct_gbpages && cpu_has_gbpages)
	184	printk(KERN_INFO "Using GB pages for direct mapping\n");
	185	else
	186	direct_gbpages = 0;
	187	}
	188	#else
	189	static inline void init_gbpages(void)
	190	{
	191	}
	192	#endif
	193
	194	/*
	195	* Setup the direct mapping of the physical memory at PAGE_OFFSET.
	196	* This runs before bootmem is initialized and gets pages directly from
	197	* the physical memory. To access them they are temporarily mapped.
	198	*/
	199	unsigned long __init_refok init_memory_mapping(unsigned long start,
	200	unsigned long end)
	201	{
	202	unsigned long page_size_mask = 0;
	203	unsigned long start_pfn, end_pfn;
c77a3b59	204	unsigned long ret = 0;
f765090a	205	unsigned long pos;
f765090a PE	206
	207	struct map_range mr[NR_RANGE_MR];
	208	int nr_range, i;
	209	int use_pse, use_gbpages;
	210
	211	printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end);
	212
	213	if (!after_bootmem)
	214	init_gbpages();
	215
f8561296	216	#if defined(CONFIG_DEBUG_PAGEALLOC) \|\| defined(CONFIG_KMEMCHECK)
f765090a PE	217	/*
	218	* For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
	219	* This will simplify cpa(), which otherwise needs to support splitting
	220	* large pages into small in interrupt context, etc.
	221	*/
	222	use_pse = use_gbpages = 0;
	223	#else
	224	use_pse = cpu_has_pse;
	225	use_gbpages = direct_gbpages;
	226	#endif
	227
f765090a PE	228	set_nx();
	229	if (nx_enabled)
	230	printk(KERN_INFO "NX (Execute Disable) protection: active\n");
f765090a PE	231
	232	/* Enable PSE if available */
	233	if (cpu_has_pse)
	234	set_in_cr4(X86_CR4_PSE);
	235
	236	/* Enable PGE if available */
	237	if (cpu_has_pge) {
	238	set_in_cr4(X86_CR4_PGE);
	239	__supported_pte_mask \|= _PAGE_GLOBAL;
	240	}
f765090a PE	241
	242	if (use_gbpages)
	243	page_size_mask \|= 1 << PG_LEVEL_1G;
	244	if (use_pse)
	245	page_size_mask \|= 1 << PG_LEVEL_2M;
	246
	247	memset(mr, 0, sizeof(mr));
	248	nr_range = 0;
	249
	250	/* head if not big page alignment ? */
	251	start_pfn = start >> PAGE_SHIFT;
	252	pos = start_pfn << PAGE_SHIFT;
	253	#ifdef CONFIG_X86_32
	254	/*
	255	* Don't use a large page for the first 2/4MB of memory
	256	* because there are often fixed size MTRRs in there
	257	* and overlapping MTRRs into large pages can cause
	258	* slowdowns.
	259	*/
	260	if (pos == 0)
	261	end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT);
	262	else
	263	end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
	264	<< (PMD_SHIFT - PAGE_SHIFT);
	265	#else /* CONFIG_X86_64 */
	266	end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT)
	267	<< (PMD_SHIFT - PAGE_SHIFT);
	268	#endif
	269	if (end_pfn > (end >> PAGE_SHIFT))
	270	end_pfn = end >> PAGE_SHIFT;
	271	if (start_pfn < end_pfn) {
	272	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
	273	pos = end_pfn << PAGE_SHIFT;
	274	}
	275
	276	/* big page (2M) range */
	277	start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
	278	<< (PMD_SHIFT - PAGE_SHIFT);
	279	#ifdef CONFIG_X86_32
	280	end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
	281	#else /* CONFIG_X86_64 */
	282	end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
	283	<< (PUD_SHIFT - PAGE_SHIFT);
	284	if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)))
	285	end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT));
	286	#endif
	287
	288	if (start_pfn < end_pfn) {
	289	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
	290	page_size_mask & (1<<PG_LEVEL_2M));
	291	pos = end_pfn << PAGE_SHIFT;
	292	}
	293
	294	#ifdef CONFIG_X86_64
	295	/* big page (1G) range */
	296	start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
	297	<< (PUD_SHIFT - PAGE_SHIFT);
	298	end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
	299	if (start_pfn < end_pfn) {
	300	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
	301	page_size_mask &
	302	((1<<PG_LEVEL_2M)\|(1<<PG_LEVEL_1G)));
	303	pos = end_pfn << PAGE_SHIFT;
	304	}
305
306	/* tail is not big page (1G) alignment */
307	start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
308	<< (PMD_SHIFT - PAGE_SHIFT);
309	end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
310	if (start_pfn < end_pfn) {
311	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
312	page_size_mask & (1<<PG_LEVEL_2M));
313	pos = end_pfn << PAGE_SHIFT;
314	}
315	#endif
316
317	/* tail is not big page (2M) alignment */
318	start_pfn = pos>>PAGE_SHIFT;
319	end_pfn = end>>PAGE_SHIFT;
320	nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
321
322	/* try to merge same page size and continuous */
323	for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
324	unsigned long old_start;
325	if (mr[i].end != mr[i+1].start \|\|
326	mr[i].page_size_mask != mr[i+1].page_size_mask)
327	continue;
328	/* move it */
329	old_start = mr[i].start;
330	memmove(&mr[i], &mr[i+1],
331	(nr_range - 1 - i) * sizeof(struct map_range));
332	mr[i--].start = old_start;
333	nr_range--;
334	}
335
336	for (i = 0; i < nr_range; i++)
337	printk(KERN_DEBUG " %010lx - %010lx page %s\n",
338	mr[i].start, mr[i].end,
339	(mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
340	(mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
341
342	/*
343	* Find space for the kernel direct mapping tables.
344	*
345	* Later we should allocate these tables in the local node of the
346	* memory mapped. Unfortunately this is done currently before the
347	* nodes are discovered.
348	*/
349	if (!after_bootmem)
350	find_early_table_space(end, use_pse, use_gbpages);
351
352	#ifdef CONFIG_X86_32
353	for (i = 0; i < nr_range; i++)
e53fb04f PE	354	kernel_physical_mapping_init(mr[i].start, mr[i].end,
e53fb04f PE	355	mr[i].page_size_mask);
f765090a PE	356	ret = end;
	357	#else /* CONFIG_X86_64 */
	358	for (i = 0; i < nr_range; i++)
	359	ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
	360	mr[i].page_size_mask);
	361	#endif
	362
	363	#ifdef CONFIG_X86_32
	364	early_ioremap_page_table_range_init();
	365
	366	load_cr3(swapper_pg_dir);
	367	#endif
	368
	369	#ifdef CONFIG_X86_64
49834396 JB	370	if (!after_bootmem && !start) {
	371	pud_t *pud;
	372	pmd_t *pmd;
	373
f765090a	374	mmu_cr4_features = read_cr4();
49834396 JB	375
	376	/*
	377	* _brk_end cannot change anymore, but it and _end may be
	378	* located on different 2M pages. cleanup_highmap(), however,
	379	* can only consider _end when it runs, so destroy any
	380	* mappings beyond _brk_end here.
	381	*/
	382	pud = pud_offset(pgd_offset_k(_brk_end), _brk_end);
	383	pmd = pmd_offset(pud, _brk_end - 1);
	384	while (++pmd <= pmd_offset(pud, (unsigned long)_end - 1))
	385	pmd_clear(pmd);
	386	}
f765090a PE	387	#endif
	388	__flush_tlb_all();
	389
298af9d8 PE	390	if (!after_bootmem && e820_table_end > e820_table_start)
	391	reserve_early(e820_table_start << PAGE_SHIFT,
	392	e820_table_end << PAGE_SHIFT, "PGTABLE");
f765090a PE	393
	394	if (!after_bootmem)
	395	early_memtest(start, end);
	396
	397	return ret >> PAGE_SHIFT;
	398	}
	399
e5b2bb55	400
540aca06 PE	401	/*
	402	* devmem_is_allowed() checks to see if /dev/mem access to a certain address
	403	* is valid. The argument is a physical page number.
	404	*
	405	*
	406	* On x86, access has to be given to the first megabyte of ram because that area
	407	* contains bios code and data regions used by X and dosemu and similar apps.
	408	* Access has to be given to non-kernel-ram areas as well, these contain the PCI
	409	* mmio resources as well as potential bios/acpi data regions.
	410	*/
	411	int devmem_is_allowed(unsigned long pagenr)
	412	{
	413	if (pagenr <= 256)
	414	return 1;
	415	if (iomem_is_exclusive(pagenr << PAGE_SHIFT))
	416	return 0;
	417	if (!page_is_ram(pagenr))
	418	return 1;
	419	return 0;
	420	}
	421
e5b2bb55 PE	422	void free_init_pages(char *what, unsigned long begin, unsigned long end)
	423	{
	424	unsigned long addr = begin;
	425
	426	if (addr >= end)
	427	return;
	428
	429	/*
	430	* If debugging page accesses then do not free this memory but
	431	* mark them not present - any buggy init-section access will
	432	* create a kernel page fault:
	433	*/
	434	#ifdef CONFIG_DEBUG_PAGEALLOC
	435	printk(KERN_INFO "debug: unmapping init memory %08lx..%08lx\n",
	436	begin, PAGE_ALIGN(end));
	437	set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
	438	#else
	439	/*
	440	* We just marked the kernel text read only above, now that
	441	* we are going to free part of that, we need to make that
	442	* writeable first.
	443	*/
	444	set_memory_rw(begin, (end - begin) >> PAGE_SHIFT);
	445
	446	printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
	447
	448	for (; addr < end; addr += PAGE_SIZE) {
	449	ClearPageReserved(virt_to_page(addr));
	450	init_page_count(virt_to_page(addr));
	451	memset((void *)(addr & ~(PAGE_SIZE-1)),
	452	POISON_FREE_INITMEM, PAGE_SIZE);
	453	free_page(addr);
	454	totalram_pages++;
	455	}
	456	#endif
	457	}
	458
	459	void free_initmem(void)
	460	{
	461	free_init_pages("unused kernel memory",
	462	(unsigned long)(&__init_begin),
	463	(unsigned long)(&__init_end));
	464	}
731ddea6 PE	465
	466	#ifdef CONFIG_BLK_DEV_INITRD
	467	void free_initrd_mem(unsigned long start, unsigned long end)
	468	{
	469	free_init_pages("initrd memory", start, end);
	470	}
	471	#endif