summaryrefslogtreecommitdiffstats
path: root/arch/s390/mm/init.c
blob: e1881c31b1cbc2384f28fb76e7e56990d8638151 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
/*
 *  arch/s390/mm/init.c
 *
 *  S390 version
 *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    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 <asm/processor.h>
#include <asm/system.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>

DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

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

void diag10(unsigned long addr)
{
        if (addr >= 0x7ff00000)
                return;
	asm volatile(
#ifdef CONFIG_64BIT
		"	sam31\n"
		"	diag	%0,%0,0x10\n"
		"0:	sam64\n"
#else
		"	diag	%0,%0,0x10\n"
		"0:\n"
#endif
		EX_TABLE(0b,0b)
		: : "a" (addr));
}

void show_mem(void)
{
        int i, total = 0, reserved = 0;
        int shared = 0, cached = 0;
	struct page *page;

        printk("Mem-info:\n");
        show_free_areas();
        printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
        i = max_mapnr;
        while (i-- > 0) {
		page = pfn_to_page(i);
                total++;
		if (PageReserved(page))
                        reserved++;
		else if (PageSwapCache(page))
                        cached++;
		else if (page_count(page))
			shared += page_count(page) - 1;
        }
        printk("%d pages of RAM\n",total);
        printk("%d reserved pages\n",reserved);
        printk("%d pages shared\n",shared);
        printk("%d pages swap cached\n",cached);
}

extern unsigned long __initdata zholes_size[];
/*
 * paging_init() sets up the page tables
 */

#ifndef CONFIG_64BIT
void __init paging_init(void)
{
        pgd_t * pg_dir;
        pte_t * pg_table;
        pte_t   pte;
	int     i;
        unsigned long tmp;
        unsigned long pfn = 0;
        unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE;
        static const int ssm_mask = 0x04000000L;
	unsigned long ro_start_pfn, ro_end_pfn;
	unsigned long zones_size[MAX_NR_ZONES];

	ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata);
	ro_end_pfn = PFN_UP((unsigned long)&__end_rodata);

	memset(zones_size, 0, sizeof(zones_size));
	zones_size[ZONE_DMA] = max_low_pfn;
	free_area_init_node(0, &contig_page_data, zones_size,
			    __pa(PAGE_OFFSET) >> PAGE_SHIFT,
			    zholes_size);

	/* unmap whole virtual address space */
	
        pg_dir = swapper_pg_dir;

	for (i = 0; i < PTRS_PER_PGD; i++)
		pmd_clear((pmd_t *) pg_dir++);
		
	/*
	 * map whole physical memory to virtual memory (identity mapping) 
	 */

        pg_dir = swapper_pg_dir;

        while (pfn < max_low_pfn) {
                /*
                 * pg_table is physical at this point
                 */
		pg_table = (pte_t *) alloc_bootmem_pages(PAGE_SIZE);

		pmd_populate_kernel(&init_mm, (pmd_t *) pg_dir, pg_table);
                pg_dir++;

                for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) {
			if (pfn >= ro_start_pfn && pfn < ro_end_pfn)
				pte = pfn_pte(pfn, __pgprot(_PAGE_RO));
			else
				pte = pfn_pte(pfn, PAGE_KERNEL);
                        if (pfn >= max_low_pfn)
				pte_val(pte) = _PAGE_TYPE_EMPTY;
			set_pte(pg_table, pte);
                        pfn++;
                }
        }

	S390_lowcore.kernel_asce = pgdir_k;

        /* enable virtual mapping in kernel mode */
	__ctl_load(pgdir_k, 1, 1);
	__ctl_load(pgdir_k, 7, 7);
	__ctl_load(pgdir_k, 13, 13);
	__raw_local_irq_ssm(ssm_mask);

        local_flush_tlb();
}

#else /* CONFIG_64BIT */

void __init paging_init(void)
{
        pgd_t * pg_dir;
	pmd_t * pm_dir;
        pte_t * pt_dir;
        pte_t   pte;
	int     i,j,k;
        unsigned long pfn = 0;
        unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) |
          _KERN_REGION_TABLE;
	static const int ssm_mask = 0x04000000L;
	unsigned long zones_size[MAX_NR_ZONES];
	unsigned long dma_pfn, high_pfn;
	unsigned long ro_start_pfn, ro_end_pfn;

	memset(zones_size, 0, sizeof(zones_size));
	dma_pfn = MAX_DMA_ADDRESS >> PAGE_SHIFT;
	high_pfn = max_low_pfn;
	ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata);
	ro_end_pfn = PFN_UP((unsigned long)&__end_rodata);

	if (dma_pfn > high_pfn)
		zones_size[ZONE_DMA] = high_pfn;
	else {
		zones_size[ZONE_DMA] = dma_pfn;
		zones_size[ZONE_NORMAL] = high_pfn - dma_pfn;
	}

	/* Initialize mem_map[].  */
	free_area_init_node(0, &contig_page_data, zones_size,
			    __pa(PAGE_OFFSET) >> PAGE_SHIFT, zholes_size);

	/*
	 * map whole physical memory to virtual memory (identity mapping) 
	 */

        pg_dir = swapper_pg_dir;
	
        for (i = 0 ; i < PTRS_PER_PGD ; i++,pg_dir++) {
	
                if (pfn >= max_low_pfn) {
                        pgd_clear(pg_dir);
                        continue;
                }          
        
		pm_dir = (pmd_t *) alloc_bootmem_pages(PAGE_SIZE * 4);
                pgd_populate(&init_mm, pg_dir, pm_dir);

                for (j = 0 ; j < PTRS_PER_PMD ; j++,pm_dir++) {
                        if (pfn >= max_low_pfn) {
                                pmd_clear(pm_dir);
                                continue; 
                        }          
                        
			pt_dir = (pte_t *) alloc_bootmem_pages(PAGE_SIZE);
                        pmd_populate_kernel(&init_mm, pm_dir, pt_dir);
	
                        for (k = 0 ; k < PTRS_PER_PTE ; k++,pt_dir++) {
				if (pfn >= ro_start_pfn && pfn < ro_end_pfn)
					pte = pfn_pte(pfn, __pgprot(_PAGE_RO));
				else
					pte = pfn_pte(pfn, PAGE_KERNEL);
				if (pfn >= max_low_pfn)
					pte_val(pte) = _PAGE_TYPE_EMPTY;
                                set_pte(pt_dir, pte);
                                pfn++;
                        }
                }
        }

	S390_lowcore.kernel_asce = pgdir_k;

        /* enable virtual mapping in kernel mode */
	__ctl_load(pgdir_k, 1, 1);
	__ctl_load(pgdir_k, 7, 7);
	__ctl_load(pgdir_k, 13, 13);
	__raw_local_irq_ssm(ssm_mask);

        local_flush_tlb();
}
#endif /* CONFIG_64BIT */

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);

        /* clear the zero-page */
        memset(empty_zero_page, 0, PAGE_SIZE);

	/* this will put all low memory onto the freelists */
	totalram_pages += free_all_bootmem();

	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",
                (unsigned long) 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)&__start_rodata,
	       PFN_ALIGN((unsigned long)&__end_rodata) - 1);
}

void free_initmem(void)
{
        unsigned long addr;

        addr = (unsigned long)(&__init_begin);
        for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
		ClearPageReserved(virt_to_page(addr));
		init_page_count(virt_to_page(addr));
		free_page(addr);
		totalram_pages++;
        }
        printk ("Freeing unused kernel memory: %ldk freed\n",
		((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10);
}

#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
        if (start < end)
                printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
        for (; start < end; start += PAGE_SIZE) {
                ClearPageReserved(virt_to_page(start));
                init_page_count(virt_to_page(start));
                free_page(start);
                totalram_pages++;
        }
}
#endif