5 * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
6 * Author(s): Hartmut Penner (hp@de.ibm.com)
8 * Derived from "arch/i386/mm/init.c"
9 * Copyright (C) 1995 Linus Torvalds
12 #include <linux/signal.h>
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/string.h>
17 #include <linux/types.h>
18 #include <linux/ptrace.h>
19 #include <linux/mman.h>
21 #include <linux/swap.h>
22 #include <linux/smp.h>
23 #include <linux/init.h>
24 #include <linux/pagemap.h>
25 #include <linux/bootmem.h>
26 #include <linux/pfn.h>
27 #include <linux/poison.h>
28 #include <linux/initrd.h>
29 #include <linux/gfp.h>
30 #include <asm/processor.h>
31 #include <asm/system.h>
32 #include <asm/uaccess.h>
33 #include <asm/pgtable.h>
34 #include <asm/pgalloc.h>
36 #include <asm/lowcore.h>
38 #include <asm/tlbflush.h>
39 #include <asm/sections.h>
41 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
43 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));
45 char empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
46 EXPORT_SYMBOL(empty_zero_page);
49 * paging_init() sets up the page tables
51 void __init paging_init(void)
53 unsigned long max_zone_pfns[MAX_NR_ZONES];
54 unsigned long pgd_type;
56 init_mm.pgd = swapper_pg_dir;
57 S390_lowcore.kernel_asce = __pa(init_mm.pgd) & PAGE_MASK;
59 /* A three level page table (4TB) is enough for the kernel space. */
60 S390_lowcore.kernel_asce |= _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH;
61 pgd_type = _REGION3_ENTRY_EMPTY;
63 S390_lowcore.kernel_asce |= _ASCE_TABLE_LENGTH;
64 pgd_type = _SEGMENT_ENTRY_EMPTY;
66 clear_table((unsigned long *) init_mm.pgd, pgd_type,
67 sizeof(unsigned long)*2048);
70 /* enable virtual mapping in kernel mode */
71 __ctl_load(S390_lowcore.kernel_asce, 1, 1);
72 __ctl_load(S390_lowcore.kernel_asce, 7, 7);
73 __ctl_load(S390_lowcore.kernel_asce, 13, 13);
74 arch_local_irq_restore(4UL << (BITS_PER_LONG - 8));
76 atomic_set(&init_mm.context.attach_count, 1);
78 sparse_memory_present_with_active_regions(MAX_NUMNODES);
80 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
81 #ifdef CONFIG_ZONE_DMA
82 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS);
84 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
85 free_area_init_nodes(max_zone_pfns);
88 void __init mem_init(void)
90 unsigned long codesize, reservedpages, datasize, initsize;
92 max_mapnr = num_physpages = max_low_pfn;
93 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
95 /* clear the zero-page */
96 memset(empty_zero_page, 0, PAGE_SIZE);
98 /* Setup guest page hinting */
101 /* this will put all low memory onto the freelists */
102 totalram_pages += free_all_bootmem();
106 codesize = (unsigned long) &_etext - (unsigned long) &_text;
107 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
108 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
109 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n",
110 nr_free_pages() << (PAGE_SHIFT-10),
111 max_mapnr << (PAGE_SHIFT-10),
113 reservedpages << (PAGE_SHIFT-10),
116 printk("Write protected kernel read-only data: %#lx - %#lx\n",
117 (unsigned long)&_stext,
118 PFN_ALIGN((unsigned long)&_eshared) - 1);
121 #ifdef CONFIG_DEBUG_PAGEALLOC
122 void kernel_map_pages(struct page *page, int numpages, int enable)
128 unsigned long address;
131 for (i = 0; i < numpages; i++) {
132 address = page_to_phys(page + i);
133 pgd = pgd_offset_k(address);
134 pud = pud_offset(pgd, address);
135 pmd = pmd_offset(pud, address);
136 pte = pte_offset_kernel(pmd, address);
138 ptep_invalidate(&init_mm, address, pte);
141 *pte = mk_pte_phys(address, __pgprot(_PAGE_TYPE_RW));
142 /* Flush cpu write queue. */
148 void free_init_pages(char *what, unsigned long begin, unsigned long end)
150 unsigned long addr = begin;
154 for (; addr < end; addr += PAGE_SIZE) {
155 ClearPageReserved(virt_to_page(addr));
156 init_page_count(virt_to_page(addr));
157 memset((void *)(addr & PAGE_MASK), POISON_FREE_INITMEM,
162 printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
165 void free_initmem(void)
167 free_init_pages("unused kernel memory",
168 (unsigned long)&__init_begin,
169 (unsigned long)&__init_end);
172 #ifdef CONFIG_BLK_DEV_INITRD
173 void free_initrd_mem(unsigned long start, unsigned long end)
175 free_init_pages("initrd memory", start, end);
179 #ifdef CONFIG_MEMORY_HOTPLUG
180 int arch_add_memory(int nid, u64 start, u64 size)
182 struct pglist_data *pgdat;
186 pgdat = NODE_DATA(nid);
187 zone = pgdat->node_zones + ZONE_MOVABLE;
188 rc = vmem_add_mapping(start, size);
191 rc = __add_pages(nid, zone, PFN_DOWN(start), PFN_DOWN(size));
193 vmem_remove_mapping(start, size);
196 #endif /* CONFIG_MEMORY_HOTPLUG */