3 * Copyright IBM Corp. 1999
4 * Author(s): Hartmut Penner (hp@de.ibm.com)
6 * Derived from "arch/i386/mm/init.c"
7 * Copyright (C) 1995 Linus Torvalds
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>
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>
24 #include <linux/memory.h>
25 #include <linux/pfn.h>
26 #include <linux/poison.h>
27 #include <linux/initrd.h>
28 #include <linux/export.h>
29 #include <linux/gfp.h>
30 #include <linux/memblock.h>
31 #include <asm/processor.h>
32 #include <linux/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>
40 #include <asm/ctl_reg.h>
42 #include <asm/set_memory.h>
44 pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir);
46 unsigned long empty_zero_page, zero_page_mask;
47 EXPORT_SYMBOL(empty_zero_page);
48 EXPORT_SYMBOL(zero_page_mask);
50 static void __init setup_zero_pages(void)
56 /* Latest machines require a mapping granularity of 512KB */
59 /* Limit number of empty zero pages for small memory sizes */
60 while (order > 2 && (totalram_pages >> 10) < (1UL << order))
63 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
65 panic("Out of memory in setup_zero_pages");
67 page = virt_to_page((void *) empty_zero_page);
68 split_page(page, order);
69 for (i = 1 << order; i > 0; i--) {
70 mark_page_reserved(page);
74 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK;
78 * paging_init() sets up the page tables
80 void __init paging_init(void)
82 unsigned long max_zone_pfns[MAX_NR_ZONES];
83 unsigned long pgd_type, asce_bits;
85 init_mm.pgd = swapper_pg_dir;
86 if (VMALLOC_END > (1UL << 42)) {
87 asce_bits = _ASCE_TYPE_REGION2 | _ASCE_TABLE_LENGTH;
88 pgd_type = _REGION2_ENTRY_EMPTY;
90 asce_bits = _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH;
91 pgd_type = _REGION3_ENTRY_EMPTY;
93 init_mm.context.asce = (__pa(init_mm.pgd) & PAGE_MASK) | asce_bits;
94 S390_lowcore.kernel_asce = init_mm.context.asce;
95 clear_table((unsigned long *) init_mm.pgd, pgd_type,
96 sizeof(unsigned long)*2048);
99 /* enable virtual mapping in kernel mode */
100 __ctl_load(S390_lowcore.kernel_asce, 1, 1);
101 __ctl_load(S390_lowcore.kernel_asce, 7, 7);
102 __ctl_load(S390_lowcore.kernel_asce, 13, 13);
103 __arch_local_irq_stosm(0x04);
105 sparse_memory_present_with_active_regions(MAX_NUMNODES);
107 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
108 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS);
109 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
110 free_area_init_nodes(max_zone_pfns);
113 void mark_rodata_ro(void)
115 unsigned long size = __end_ro_after_init - __start_ro_after_init;
117 set_memory_ro((unsigned long)__start_ro_after_init, size >> PAGE_SHIFT);
118 pr_info("Write protected read-only-after-init data: %luk\n", size >> 10);
121 void __init mem_init(void)
123 cpumask_set_cpu(0, &init_mm.context.cpu_attach_mask);
124 cpumask_set_cpu(0, mm_cpumask(&init_mm));
126 set_max_mapnr(max_low_pfn);
127 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
129 /* Setup guest page hinting */
132 /* this will put all low memory onto the freelists */
134 setup_zero_pages(); /* Setup zeroed pages. */
136 mem_init_print_info(NULL);
139 void free_initmem(void)
141 __set_memory((unsigned long) _sinittext,
142 (_einittext - _sinittext) >> PAGE_SHIFT,
143 SET_MEMORY_RW | SET_MEMORY_NX);
144 free_initmem_default(POISON_FREE_INITMEM);
147 #ifdef CONFIG_BLK_DEV_INITRD
148 void __init free_initrd_mem(unsigned long start, unsigned long end)
150 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
155 unsigned long memory_block_size_bytes(void)
158 * Make sure the memory block size is always greater
159 * or equal than the memory increment size.
161 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE, sclp.rzm);
164 #ifdef CONFIG_MEMORY_HOTPLUG
165 int arch_add_memory(int nid, u64 start, u64 size, bool for_device)
167 unsigned long zone_start_pfn, zone_end_pfn, nr_pages;
168 unsigned long start_pfn = PFN_DOWN(start);
169 unsigned long size_pages = PFN_DOWN(size);
170 pg_data_t *pgdat = NODE_DATA(nid);
174 rc = vmem_add_mapping(start, size);
178 for (i = 0; i < MAX_NR_ZONES; i++) {
179 zone = pgdat->node_zones + i;
180 if (zone_idx(zone) != ZONE_MOVABLE) {
181 /* Add range within existing zone limits, if possible */
182 zone_start_pfn = zone->zone_start_pfn;
183 zone_end_pfn = zone->zone_start_pfn +
186 /* Add remaining range to ZONE_MOVABLE */
187 zone_start_pfn = start_pfn;
188 zone_end_pfn = start_pfn + size_pages;
190 if (start_pfn < zone_start_pfn || start_pfn >= zone_end_pfn)
192 nr_pages = (start_pfn + size_pages > zone_end_pfn) ?
193 zone_end_pfn - start_pfn : size_pages;
194 rc = __add_pages(nid, zone, start_pfn, nr_pages);
197 start_pfn += nr_pages;
198 size_pages -= nr_pages;
203 vmem_remove_mapping(start, size);
207 #ifdef CONFIG_MEMORY_HOTREMOVE
208 int arch_remove_memory(u64 start, u64 size)
211 * There is no hardware or firmware interface which could trigger a
212 * hot memory remove on s390. So there is nothing that needs to be
218 #endif /* CONFIG_MEMORY_HOTPLUG */