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>
28 #include <asm/processor.h>
29 #include <asm/system.h>
30 #include <asm/uaccess.h>
31 #include <asm/pgtable.h>
32 #include <asm/pgalloc.h>
34 #include <asm/lowcore.h>
36 #include <asm/tlbflush.h>
37 #include <asm/sections.h>
39 DEFINE_PER_CPU(struct mmu_gather
, mmu_gathers
);
41 pgd_t swapper_pg_dir
[PTRS_PER_PGD
] __attribute__((__aligned__(PAGE_SIZE
)));
42 char empty_zero_page
[PAGE_SIZE
] __attribute__((__aligned__(PAGE_SIZE
)));
44 void diag10(unsigned long addr
)
46 if (addr
>= 0x7ff00000)
53 ".section __ex_table,\"a\"\n"
62 ".section __ex_table,\"a\"\n"
72 int i
, total
= 0, reserved
= 0;
73 int shared
= 0, cached
= 0;
75 printk("Mem-info:\n");
77 printk("Free swap: %6ldkB\n", nr_swap_pages
<<(PAGE_SHIFT
-10));
81 if (PageReserved(mem_map
+i
))
83 else if (PageSwapCache(mem_map
+i
))
85 else if (page_count(mem_map
+i
))
86 shared
+= page_count(mem_map
+i
) - 1;
88 printk("%d pages of RAM\n",total
);
89 printk("%d reserved pages\n",reserved
);
90 printk("%d pages shared\n",shared
);
91 printk("%d pages swap cached\n",cached
);
94 extern unsigned long __initdata zholes_size
[];
96 * paging_init() sets up the page tables
100 void __init
paging_init(void)
107 unsigned long pfn
= 0;
108 unsigned long pgdir_k
= (__pa(swapper_pg_dir
) & PAGE_MASK
) | _KERNSEG_TABLE
;
109 static const int ssm_mask
= 0x04000000L
;
110 unsigned long ro_start_pfn
, ro_end_pfn
;
112 ro_start_pfn
= PFN_DOWN((unsigned long)&__start_rodata
);
113 ro_end_pfn
= PFN_UP((unsigned long)&__end_rodata
);
115 /* unmap whole virtual address space */
117 pg_dir
= swapper_pg_dir
;
119 for (i
=0;i
<KERNEL_PGD_PTRS
;i
++)
120 pmd_clear((pmd_t
*)pg_dir
++);
123 * map whole physical memory to virtual memory (identity mapping)
126 pg_dir
= swapper_pg_dir
;
128 while (pfn
< max_low_pfn
) {
130 * pg_table is physical at this point
132 pg_table
= (pte_t
*) alloc_bootmem_pages(PAGE_SIZE
);
134 pg_dir
->pgd0
= (_PAGE_TABLE
| __pa(pg_table
));
135 pg_dir
->pgd1
= (_PAGE_TABLE
| (__pa(pg_table
)+1024));
136 pg_dir
->pgd2
= (_PAGE_TABLE
| (__pa(pg_table
)+2048));
137 pg_dir
->pgd3
= (_PAGE_TABLE
| (__pa(pg_table
)+3072));
140 for (tmp
= 0 ; tmp
< PTRS_PER_PTE
; tmp
++,pg_table
++) {
141 if (pfn
>= ro_start_pfn
&& pfn
< ro_end_pfn
)
142 pte
= pfn_pte(pfn
, __pgprot(_PAGE_RO
));
144 pte
= pfn_pte(pfn
, PAGE_KERNEL
);
145 if (pfn
>= max_low_pfn
)
146 pte_clear(&init_mm
, 0, &pte
);
147 set_pte(pg_table
, pte
);
152 S390_lowcore
.kernel_asce
= pgdir_k
;
154 /* enable virtual mapping in kernel mode */
155 __asm__
__volatile__(" LCTL 1,1,%0\n"
159 : : "m" (pgdir_k
), "m" (ssm_mask
));
164 unsigned long zones_size
[MAX_NR_ZONES
];
166 memset(zones_size
, 0, sizeof(zones_size
));
167 zones_size
[ZONE_DMA
] = max_low_pfn
;
168 free_area_init_node(0, &contig_page_data
, zones_size
,
169 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
,
175 #else /* CONFIG_64BIT */
177 void __init
paging_init(void)
184 unsigned long pfn
= 0;
185 unsigned long pgdir_k
= (__pa(swapper_pg_dir
) & PAGE_MASK
) |
187 static const int ssm_mask
= 0x04000000L
;
188 unsigned long zones_size
[MAX_NR_ZONES
];
189 unsigned long dma_pfn
, high_pfn
;
190 unsigned long ro_start_pfn
, ro_end_pfn
;
192 memset(zones_size
, 0, sizeof(zones_size
));
193 dma_pfn
= MAX_DMA_ADDRESS
>> PAGE_SHIFT
;
194 high_pfn
= max_low_pfn
;
195 ro_start_pfn
= PFN_DOWN((unsigned long)&__start_rodata
);
196 ro_end_pfn
= PFN_UP((unsigned long)&__end_rodata
);
198 if (dma_pfn
> high_pfn
)
199 zones_size
[ZONE_DMA
] = high_pfn
;
201 zones_size
[ZONE_DMA
] = dma_pfn
;
202 zones_size
[ZONE_NORMAL
] = high_pfn
- dma_pfn
;
205 /* Initialize mem_map[]. */
206 free_area_init_node(0, &contig_page_data
, zones_size
,
207 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
, zholes_size
);
210 * map whole physical memory to virtual memory (identity mapping)
213 pg_dir
= swapper_pg_dir
;
215 for (i
= 0 ; i
< PTRS_PER_PGD
; i
++,pg_dir
++) {
217 if (pfn
>= max_low_pfn
) {
222 pm_dir
= (pmd_t
*) alloc_bootmem_pages(PAGE_SIZE
* 4);
223 pgd_populate(&init_mm
, pg_dir
, pm_dir
);
225 for (j
= 0 ; j
< PTRS_PER_PMD
; j
++,pm_dir
++) {
226 if (pfn
>= max_low_pfn
) {
231 pt_dir
= (pte_t
*) alloc_bootmem_pages(PAGE_SIZE
);
232 pmd_populate_kernel(&init_mm
, pm_dir
, pt_dir
);
234 for (k
= 0 ; k
< PTRS_PER_PTE
; k
++,pt_dir
++) {
235 if (pfn
>= ro_start_pfn
&& pfn
< ro_end_pfn
)
236 pte
= pfn_pte(pfn
, __pgprot(_PAGE_RO
));
238 pte
= pfn_pte(pfn
, PAGE_KERNEL
);
239 if (pfn
>= max_low_pfn
) {
240 pte_clear(&init_mm
, 0, &pte
);
243 set_pte(pt_dir
, pte
);
249 S390_lowcore
.kernel_asce
= pgdir_k
;
251 /* enable virtual mapping in kernel mode */
252 __asm__
__volatile__("lctlg 1,1,%0\n\t"
256 : :"m" (pgdir_k
), "m" (ssm_mask
));
262 #endif /* CONFIG_64BIT */
264 void __init
mem_init(void)
266 unsigned long codesize
, reservedpages
, datasize
, initsize
;
268 max_mapnr
= num_physpages
= max_low_pfn
;
269 high_memory
= (void *) __va(max_low_pfn
* PAGE_SIZE
);
271 /* clear the zero-page */
272 memset(empty_zero_page
, 0, PAGE_SIZE
);
274 /* this will put all low memory onto the freelists */
275 totalram_pages
+= free_all_bootmem();
279 codesize
= (unsigned long) &_etext
- (unsigned long) &_text
;
280 datasize
= (unsigned long) &_edata
- (unsigned long) &_etext
;
281 initsize
= (unsigned long) &__init_end
- (unsigned long) &__init_begin
;
282 printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n",
283 (unsigned long) nr_free_pages() << (PAGE_SHIFT
-10),
284 max_mapnr
<< (PAGE_SHIFT
-10),
286 reservedpages
<< (PAGE_SHIFT
-10),
289 printk("Write protected kernel read-only data: %#lx - %#lx\n",
290 (unsigned long)&__start_rodata
,
291 PFN_ALIGN((unsigned long)&__end_rodata
) - 1);
294 void free_initmem(void)
298 addr
= (unsigned long)(&__init_begin
);
299 for (; addr
< (unsigned long)(&__init_end
); addr
+= PAGE_SIZE
) {
300 ClearPageReserved(virt_to_page(addr
));
301 init_page_count(virt_to_page(addr
));
305 printk ("Freeing unused kernel memory: %ldk freed\n",
306 ((unsigned long)&__init_end
- (unsigned long)&__init_begin
) >> 10);
309 #ifdef CONFIG_BLK_DEV_INITRD
310 void free_initrd_mem(unsigned long start
, unsigned long end
)
313 printk ("Freeing initrd memory: %ldk freed\n", (end
- start
) >> 10);
314 for (; start
< end
; start
+= PAGE_SIZE
) {
315 ClearPageReserved(virt_to_page(start
));
316 init_page_count(virt_to_page(start
));