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 <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>
40 #include <asm/ctl_reg.h>
43 pgd_t swapper_pg_dir
[PTRS_PER_PGD
] __section(.bss
..swapper_pg_dir
);
45 unsigned long empty_zero_page
, zero_page_mask
;
46 EXPORT_SYMBOL(empty_zero_page
);
47 EXPORT_SYMBOL(zero_page_mask
);
49 static void __init
setup_zero_pages(void)
55 /* Latest machines require a mapping granularity of 512KB */
58 /* Limit number of empty zero pages for small memory sizes */
59 while (order
> 2 && (totalram_pages
>> 10) < (1UL << order
))
62 empty_zero_page
= __get_free_pages(GFP_KERNEL
| __GFP_ZERO
, order
);
64 panic("Out of memory in setup_zero_pages");
66 page
= virt_to_page((void *) empty_zero_page
);
67 split_page(page
, order
);
68 for (i
= 1 << order
; i
> 0; i
--) {
69 mark_page_reserved(page
);
73 zero_page_mask
= ((PAGE_SIZE
<< order
) - 1) & PAGE_MASK
;
77 * paging_init() sets up the page tables
79 void __init
paging_init(void)
81 unsigned long max_zone_pfns
[MAX_NR_ZONES
];
82 unsigned long pgd_type
, asce_bits
;
84 init_mm
.pgd
= swapper_pg_dir
;
85 if (VMALLOC_END
> (1UL << 42)) {
86 asce_bits
= _ASCE_TYPE_REGION2
| _ASCE_TABLE_LENGTH
;
87 pgd_type
= _REGION2_ENTRY_EMPTY
;
89 asce_bits
= _ASCE_TYPE_REGION3
| _ASCE_TABLE_LENGTH
;
90 pgd_type
= _REGION3_ENTRY_EMPTY
;
92 init_mm
.context
.asce
= (__pa(init_mm
.pgd
) & PAGE_MASK
) | asce_bits
;
93 S390_lowcore
.kernel_asce
= init_mm
.context
.asce
;
94 clear_table((unsigned long *) init_mm
.pgd
, pgd_type
,
95 sizeof(unsigned long)*2048);
98 /* enable virtual mapping in kernel mode */
99 __ctl_load(S390_lowcore
.kernel_asce
, 1, 1);
100 __ctl_load(S390_lowcore
.kernel_asce
, 7, 7);
101 __ctl_load(S390_lowcore
.kernel_asce
, 13, 13);
102 __arch_local_irq_stosm(0x04);
104 sparse_memory_present_with_active_regions(MAX_NUMNODES
);
106 memset(max_zone_pfns
, 0, sizeof(max_zone_pfns
));
107 max_zone_pfns
[ZONE_DMA
] = PFN_DOWN(MAX_DMA_ADDRESS
);
108 max_zone_pfns
[ZONE_NORMAL
] = max_low_pfn
;
109 free_area_init_nodes(max_zone_pfns
);
112 void mark_rodata_ro(void)
114 unsigned long size
= __end_ro_after_init
- __start_ro_after_init
;
116 set_memory_ro((unsigned long)__start_ro_after_init
, size
>> PAGE_SHIFT
);
117 pr_info("Write protected read-only-after-init data: %luk\n", size
>> 10);
120 void __init
mem_init(void)
122 cpumask_set_cpu(0, &init_mm
.context
.cpu_attach_mask
);
123 cpumask_set_cpu(0, mm_cpumask(&init_mm
));
125 set_max_mapnr(max_low_pfn
);
126 high_memory
= (void *) __va(max_low_pfn
* PAGE_SIZE
);
128 /* Setup guest page hinting */
131 /* this will put all low memory onto the freelists */
133 setup_zero_pages(); /* Setup zeroed pages. */
135 mem_init_print_info(NULL
);
138 void free_initmem(void)
140 free_initmem_default(POISON_FREE_INITMEM
);
143 #ifdef CONFIG_BLK_DEV_INITRD
144 void __init
free_initrd_mem(unsigned long start
, unsigned long end
)
146 free_reserved_area((void *)start
, (void *)end
, POISON_FREE_INITMEM
,
151 #ifdef CONFIG_MEMORY_HOTPLUG
152 int arch_add_memory(int nid
, u64 start
, u64 size
, bool for_device
)
154 unsigned long normal_end_pfn
= PFN_DOWN(memblock_end_of_DRAM());
155 unsigned long dma_end_pfn
= PFN_DOWN(MAX_DMA_ADDRESS
);
156 unsigned long start_pfn
= PFN_DOWN(start
);
157 unsigned long size_pages
= PFN_DOWN(size
);
158 unsigned long nr_pages
;
161 rc
= vmem_add_mapping(start
, size
);
165 while (size_pages
> 0) {
166 if (start_pfn
< dma_end_pfn
) {
167 nr_pages
= (start_pfn
+ size_pages
> dma_end_pfn
) ?
168 dma_end_pfn
- start_pfn
: size_pages
;
169 zone_enum
= ZONE_DMA
;
170 } else if (start_pfn
< normal_end_pfn
) {
171 nr_pages
= (start_pfn
+ size_pages
> normal_end_pfn
) ?
172 normal_end_pfn
- start_pfn
: size_pages
;
173 zone_enum
= ZONE_NORMAL
;
175 nr_pages
= size_pages
;
176 zone_enum
= ZONE_MOVABLE
;
178 rc
= __add_pages(nid
, NODE_DATA(nid
)->node_zones
+ zone_enum
,
179 start_pfn
, size_pages
);
182 start_pfn
+= nr_pages
;
183 size_pages
-= nr_pages
;
186 vmem_remove_mapping(start
, size
);
190 unsigned long memory_block_size_bytes(void)
193 * Make sure the memory block size is always greater
194 * or equal than the memory increment size.
196 return max_t(unsigned long, MIN_MEMORY_BLOCK_SIZE
, sclp
.rzm
);
199 #ifdef CONFIG_MEMORY_HOTREMOVE
200 int arch_remove_memory(u64 start
, u64 size
)
203 * There is no hardware or firmware interface which could trigger a
204 * hot memory remove on s390. So there is nothing that needs to be
210 #endif /* CONFIG_MEMORY_HOTPLUG */