[mirror_ubuntu-jammy-kernel.git] / arch / x86 / mm / init.c

#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/system.h>
#include <asm/tlbflush.h>

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
;

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;
	e820_table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT,
					tables, PAGE_SIZE);
#else /* CONFIG_X86_64 */
	start = 0x8000;
	e820_table_start = find_e820_area(start, end, tables, PAGE_SIZE);
#endif
	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 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();

#ifdef CONFIG_DEBUG_PAGEALLOC
	/*
	 * 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

#ifdef CONFIG_X86_32
#ifdef CONFIG_X86_PAE
	set_nx();
	if (nx_enabled)
		printk(KERN_INFO "NX (Execute Disable) protection: active\n");
#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;
	}
#endif

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