[deliverable/linux.git] / arch / s390 / mm / init.c

/*
 *  S390 version
 *    Copyright IBM Corp. 1999
 *    Author(s): Hartmut Penner (hp@de.ibm.com)
 *
 *  Derived from "arch/i386/mm/init.c"
 *    Copyright (C) 1995  Linus Torvalds
 */

#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <linux/pagemap.h>
#include <linux/bootmem.h>
#include <linux/pfn.h>
#include <linux/poison.h>
#include <linux/initrd.h>
#include <linux/export.h>
#include <linux/gfp.h>
#include <asm/processor.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/dma.h>
#include <asm/lowcore.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
#include <asm/sections.h>
#include <asm/ctl_reg.h>

pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));

unsigned long empty_zero_page, zero_page_mask;
EXPORT_SYMBOL(empty_zero_page);

static unsigned long __init setup_zero_pages(void)
{
	struct cpuid cpu_id;
	unsigned int order;
	unsigned long size;
	struct page *page;
	int i;

	get_cpu_id(&cpu_id);
	switch (cpu_id.machine) {
	case 0x9672:	/* g5 */
	case 0x2064:	/* z900 */
	case 0x2066:	/* z900 */
	case 0x2084:	/* z990 */
	case 0x2086:	/* z990 */
	case 0x2094:	/* z9-109 */
	case 0x2096:	/* z9-109 */
		order = 0;
		break;
	case 0x2097:	/* z10 */
	case 0x2098:	/* z10 */
	case 0x2817:	/* z196 */
	case 0x2818:	/* z196 */
		order = 2;
		break;
	case 0x2827:	/* zEC12 */
	default:
		order = 5;
		break;
	}
	/* Limit number of empty zero pages for small memory sizes */
	if (order > 2 && totalram_pages <= 16384)
		order = 2;

	empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
	if (!empty_zero_page)
		panic("Out of memory in setup_zero_pages");

	page = virt_to_page((void *) empty_zero_page);
	split_page(page, order);
	for (i = 1 << order; i > 0; i--) {
		SetPageReserved(page);
		page++;
	}

	size = PAGE_SIZE << order;
	zero_page_mask = (size - 1) & PAGE_MASK;

	return 1UL << order;
}

/*
 * paging_init() sets up the page tables
 */
void __init paging_init(void)
{
	unsigned long max_zone_pfns[MAX_NR_ZONES];
	unsigned long pgd_type, asce_bits;

	init_mm.pgd = swapper_pg_dir;
#ifdef CONFIG_64BIT
	if (VMALLOC_END > (1UL << 42)) {
		asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH;
		pgd_type = _REGION2_ENTRY_EMPTY;
	} else {
		asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH;
		pgd_type = _REGION3_ENTRY_EMPTY;
	}
#else
	asce_bits = _ASCE_TABLE_LENGTH;
	pgd_type = _SEGMENT_ENTRY_EMPTY;
#endif
	S390_lowcore.kernel_asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits;
	clear_table((unsigned long *) init_mm.pgd, pgd_type,
		    sizeof(unsigned long)*2048);
	vmem_map_init();

        /* enable virtual mapping in kernel mode */
	__ctl_load(S390_lowcore.kernel_asce, 1, 1);
	__ctl_load(S390_lowcore.kernel_asce, 7, 7);
	__ctl_load(S390_lowcore.kernel_asce, 13, 13);
	arch_local_irq_restore(4UL << (BITS_PER_LONG - 8));

	atomic_set(&init_mm.context.attach_count, 1);

	sparse_memory_present_with_active_regions(MAX_NUMNODES);
	sparse_init();
	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
	max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS);
	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
	free_area_init_nodes(max_zone_pfns);
}

void __init mem_init(void)
{
	unsigned long codesize, reservedpages, datasize, initsize;

        max_mapnr = num_physpages = max_low_pfn;
        high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);

	/* Setup guest page hinting */
	cmma_init();

	/* this will put all low memory onto the freelists */
	totalram_pages += free_all_bootmem();
	totalram_pages -= setup_zero_pages();	/* Setup zeroed pages. */

	reservedpages = 0;

	codesize =  (unsigned long) &_etext - (unsigned long) &_text;
	datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
        printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n",
		nr_free_pages() << (PAGE_SHIFT-10),
                max_mapnr << (PAGE_SHIFT-10),
                codesize >> 10,
                reservedpages << (PAGE_SHIFT-10),
                datasize >>10,
                initsize >> 10);
	printk("Write protected kernel read-only data: %#lx - %#lx\n",
	       (unsigned long)&_stext,
	       PFN_ALIGN((unsigned long)&_eshared) - 1);
}

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

	if (begin >= end)
		return;
	for (; addr < end; addr += PAGE_SIZE) {
		ClearPageReserved(virt_to_page(addr));
		init_page_count(virt_to_page(addr));
		memset((void *)(addr & PAGE_MASK), POISON_FREE_INITMEM,
		       PAGE_SIZE);
		free_page(addr);
		totalram_pages++;
	}
	printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
}

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

#ifdef CONFIG_BLK_DEV_INITRD
void __init free_initrd_mem(unsigned long start, unsigned long end)
{
	free_init_pages("initrd memory", start, end);
}
#endif

#ifdef CONFIG_MEMORY_HOTPLUG
int arch_add_memory(int nid, u64 start, u64 size)
{
	unsigned long zone_start_pfn, zone_end_pfn, nr_pages;
	unsigned long start_pfn = PFN_DOWN(start);
	unsigned long size_pages = PFN_DOWN(size);
	struct zone *zone;
	int rc;

	rc = vmem_add_mapping(start, size);
	if (rc)
		return rc;
	for_each_zone(zone) {
		if (zone_idx(zone) != ZONE_MOVABLE) {
			/* Add range within existing zone limits */
			zone_start_pfn = zone->zone_start_pfn;
			zone_end_pfn = zone->zone_start_pfn +
				       zone->spanned_pages;
		} else {
			/* Add remaining range to ZONE_MOVABLE */
			zone_start_pfn = start_pfn;
			zone_end_pfn = start_pfn + size_pages;
		}
		if (start_pfn < zone_start_pfn || start_pfn >= zone_end_pfn)
			continue;
		nr_pages = (start_pfn + size_pages > zone_end_pfn) ?
			   zone_end_pfn - start_pfn : size_pages;
		rc = __add_pages(nid, zone, start_pfn, nr_pages);
		if (rc)
			break;
		start_pfn += nr_pages;
		size_pages -= nr_pages;
		if (!size_pages)
			break;
	}
	if (rc)
		vmem_remove_mapping(start, size);
	return rc;
}

#ifdef CONFIG_MEMORY_HOTREMOVE
int arch_remove_memory(u64 start, u64 size)
{
	/*
	 * There is no hardware or firmware interface which could trigger a
	 * hot memory remove on s390. So there is nothing that needs to be
	 * implemented.
	 */
	return -EBUSY;
}
#endif
#endif /* CONFIG_MEMORY_HOTPLUG */
Commit	Line	Data
1da177e4	1	/*
1da177e4	2	* S390 version
a53c8fab	3	* Copyright IBM Corp. 1999
1da177e4 LT	4	* Author(s): Hartmut Penner (hp@de.ibm.com)
	5	*
	6	* Derived from "arch/i386/mm/init.c"
	7	* Copyright (C) 1995 Linus Torvalds
	8	*/
	9
1da177e4 LT	10	#include <linux/signal.h>
	11	#include <linux/sched.h>
	12	#include <linux/kernel.h>
	13	#include <linux/errno.h>
	14	#include <linux/string.h>
	15	#include <linux/types.h>
	16	#include <linux/ptrace.h>
	17	#include <linux/mman.h>
	18	#include <linux/mm.h>
	19	#include <linux/swap.h>
	20	#include <linux/smp.h>
	21	#include <linux/init.h>
	22	#include <linux/pagemap.h>
	23	#include <linux/bootmem.h>
d882b172	24	#include <linux/pfn.h>
028d9b3c	25	#include <linux/poison.h>
2b67fc46	26	#include <linux/initrd.h>
3a4c5d59	27	#include <linux/export.h>
5a0e3ad6	28	#include <linux/gfp.h>
1da177e4	29	#include <asm/processor.h>
1da177e4 LT	30	#include <asm/uaccess.h>
	31	#include <asm/pgtable.h>
	32	#include <asm/pgalloc.h>
	33	#include <asm/dma.h>
	34	#include <asm/lowcore.h>
	35	#include <asm/tlb.h>
	36	#include <asm/tlbflush.h>
d882b172	37	#include <asm/sections.h>
a0616cde	38	#include <asm/ctl_reg.h>
1da177e4	39
1da177e4	40	pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));
1485c5c8	41
238ec4ef	42	unsigned long empty_zero_page, zero_page_mask;
1485c5c8	43	EXPORT_SYMBOL(empty_zero_page);
1da177e4	44
5e249d6e	45	static unsigned long __init setup_zero_pages(void)
238ec4ef MS	46	{
	47	struct cpuid cpu_id;
	48	unsigned int order;
	49	unsigned long size;
	50	struct page *page;
	51	int i;
	52
	53	get_cpu_id(&cpu_id);
	54	switch (cpu_id.machine) {
	55	case 0x9672: /* g5 */
	56	case 0x2064: /* z900 */
	57	case 0x2066: /* z900 */
	58	case 0x2084: /* z990 */
	59	case 0x2086: /* z990 */
	60	case 0x2094: /* z9-109 */
	61	case 0x2096: /* z9-109 */
	62	order = 0;
	63	break;
	64	case 0x2097: /* z10 */
	65	case 0x2098: /* z10 */
7919e91b MS	66	case 0x2817: /* z196 */
7919e91b MS	67	case 0x2818: /* z196 */
238ec4ef MS	68	order = 2;
238ec4ef MS	69	break;
7919e91b MS	70	case 0x2827: /* zEC12 */
	71	default:
	72	order = 5;
	73	break;
238ec4ef	74	}
7919e91b MS	75	/* Limit number of empty zero pages for small memory sizes */
	76	if (order > 2 && totalram_pages <= 16384)
	77	order = 2;
238ec4ef MS	78
	79	empty_zero_page = __get_free_pages(GFP_KERNEL \| __GFP_ZERO, order);
	80	if (!empty_zero_page)
	81	panic("Out of memory in setup_zero_pages");
	82
	83	page = virt_to_page((void *) empty_zero_page);
	84	split_page(page, order);
	85	for (i = 1 << order; i > 0; i--) {
	86	SetPageReserved(page);
	87	page++;
	88	}
	89
	90	size = PAGE_SIZE << order;
	91	zero_page_mask = (size - 1) & PAGE_MASK;
	92
	93	return 1UL << order;
	94	}
	95
1da177e4 LT	96	/*
	97	* paging_init() sets up the page tables
	98	*/
1da177e4 LT	99	void __init paging_init(void)
1da177e4 LT	100	{
39b742f9	101	unsigned long max_zone_pfns[MAX_NR_ZONES];
14045ebf	102	unsigned long pgd_type, asce_bits;
d882b172	103
3610cce8	104	init_mm.pgd = swapper_pg_dir;
f4eb07c1	105	#ifdef CONFIG_64BIT
14045ebf MS	106	if (VMALLOC_END > (1UL << 42)) {
	107	asce_bits = _ASCE_TYPE_REGION2 \| _ASCE_TABLE_LENGTH;
	108	pgd_type = _REGION2_ENTRY_EMPTY;
	109	} else {
	110	asce_bits = _ASCE_TYPE_REGION3 \| _ASCE_TABLE_LENGTH;
	111	pgd_type = _REGION3_ENTRY_EMPTY;
	112	}
f4eb07c1	113	#else
14045ebf	114	asce_bits = _ASCE_TABLE_LENGTH;
3610cce8	115	pgd_type = _SEGMENT_ENTRY_EMPTY;
f4eb07c1	116	#endif
14045ebf	117	S390_lowcore.kernel_asce = (__pa(init_mm.pgd) & PAGE_MASK) \| asce_bits;
3610cce8 MS	118	clear_table((unsigned long *) init_mm.pgd, pgd_type,
3610cce8 MS	119	sizeof(unsigned long)*2048);
f4eb07c1	120	vmem_map_init();
1da177e4	121
1da177e4	122	/* enable virtual mapping in kernel mode */
3610cce8 MS	123	__ctl_load(S390_lowcore.kernel_asce, 1, 1);
	124	__ctl_load(S390_lowcore.kernel_asce, 7, 7);
	125	__ctl_load(S390_lowcore.kernel_asce, 13, 13);
df9ee292	126	arch_local_irq_restore(4UL << (BITS_PER_LONG - 8));
1da177e4	127
050eef36 MS	128	atomic_set(&init_mm.context.attach_count, 1);
050eef36 MS	129
17f34580 HC	130	sparse_memory_present_with_active_regions(MAX_NUMNODES);
17f34580 HC	131	sparse_init();
39b742f9 HC	132	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
	133	max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS);
	134	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
	135	free_area_init_nodes(max_zone_pfns);
1da177e4	136	}
1da177e4 LT	137
	138	void __init mem_init(void)
	139	{
	140	unsigned long codesize, reservedpages, datasize, initsize;
	141
	142	max_mapnr = num_physpages = max_low_pfn;
	143	high_memory = (void ) __va(max_low_pfn PAGE_SIZE);
	144
45e576b1 MS	145	/* Setup guest page hinting */
	146	cmma_init();
	147
1da177e4 LT	148	/* this will put all low memory onto the freelists */
1da177e4 LT	149	totalram_pages += free_all_bootmem();
238ec4ef	150	totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */
1da177e4 LT	151
	152	reservedpages = 0;
	153
	154	codesize = (unsigned long) &_etext - (unsigned long) &_text;
	155	datasize = (unsigned long) &_edata - (unsigned long) &_etext;
	156	initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
	157	printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n",
cc013a88	158	nr_free_pages() << (PAGE_SHIFT-10),
1da177e4 LT	159	max_mapnr << (PAGE_SHIFT-10),
	160	codesize >> 10,
	161	reservedpages << (PAGE_SHIFT-10),
	162	datasize >>10,
	163	initsize >> 10);
d882b172	164	printk("Write protected kernel read-only data: %#lx - %#lx\n",
162e006e HC	165	(unsigned long)&_stext,
162e006e HC	166	PFN_ALIGN((unsigned long)&_eshared) - 1);
1da177e4 LT	167	}
1da177e4 LT	168
d96221ab	169	void free_init_pages(char *what, unsigned long begin, unsigned long end)
1da177e4	170	{
d96221ab	171	unsigned long addr = begin;
1da177e4	172
d96221ab HC	173	if (begin >= end)
	174	return;
	175	for (; addr < end; addr += PAGE_SIZE) {
1da177e4	176	ClearPageReserved(virt_to_page(addr));
7835e98b	177	init_page_count(virt_to_page(addr));
d96221ab HC	178	memset((void *)(addr & PAGE_MASK), POISON_FREE_INITMEM,
d96221ab HC	179	PAGE_SIZE);
1da177e4 LT	180	free_page(addr);
1da177e4 LT	181	totalram_pages++;
d96221ab HC	182	}
	183	printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
	184	}
	185
	186	void free_initmem(void)
	187	{
	188	free_init_pages("unused kernel memory",
	189	(unsigned long)&__init_begin,
	190	(unsigned long)&__init_end);
1da177e4 LT	191	}
	192
	193	#ifdef CONFIG_BLK_DEV_INITRD
5e249d6e	194	void __init free_initrd_mem(unsigned long start, unsigned long end)
1da177e4	195	{
d96221ab	196	free_init_pages("initrd memory", start, end);
1da177e4 LT	197	}
1da177e4 LT	198	#endif
421c175c HC	199
	200	#ifdef CONFIG_MEMORY_HOTPLUG
	201	int arch_add_memory(int nid, u64 start, u64 size)
	202	{
892365ab GS	203	unsigned long zone_start_pfn, zone_end_pfn, nr_pages;
	204	unsigned long start_pfn = PFN_DOWN(start);
	205	unsigned long size_pages = PFN_DOWN(size);
421c175c HC	206	struct zone *zone;
	207	int rc;
	208
421c175c HC	209	rc = vmem_add_mapping(start, size);
	210	if (rc)
	211	return rc;
892365ab GS	212	for_each_zone(zone) {
	213	if (zone_idx(zone) != ZONE_MOVABLE) {
	214	/* Add range within existing zone limits */
	215	zone_start_pfn = zone->zone_start_pfn;
	216	zone_end_pfn = zone->zone_start_pfn +
	217	zone->spanned_pages;
	218	} else {
	219	/* Add remaining range to ZONE_MOVABLE */
	220	zone_start_pfn = start_pfn;
	221	zone_end_pfn = start_pfn + size_pages;
	222	}
	223	if (start_pfn < zone_start_pfn \|\| start_pfn >= zone_end_pfn)
	224	continue;
	225	nr_pages = (start_pfn + size_pages > zone_end_pfn) ?
	226	zone_end_pfn - start_pfn : size_pages;
	227	rc = __add_pages(nid, zone, start_pfn, nr_pages);
	228	if (rc)
	229	break;
	230	start_pfn += nr_pages;
	231	size_pages -= nr_pages;
	232	if (!size_pages)
	233	break;
	234	}
421c175c HC	235	if (rc)
	236	vmem_remove_mapping(start, size);
	237	return rc;
	238	}
24d335ca WC	239
	240	#ifdef CONFIG_MEMORY_HOTREMOVE
	241	int arch_remove_memory(u64 start, u64 size)
	242	{
	243	/*
	244	* There is no hardware or firmware interface which could trigger a
	245	* hot memory remove on s390. So there is nothing that needs to be
	246	* implemented.
	247	*/
	248	return -EBUSY;
	249	}
	250	#endif
421c175c	251	#endif /* CONFIG_MEMORY_HOTPLUG */