1 /*
2 * arch/s390/mm/init.c
3 *
4 * S390 version
5 * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
6 * Author(s): Hartmut Penner (hp@de.ibm.com)
7 *
8 * Derived from "arch/i386/mm/init.c"
9 * Copyright (C) 1995 Linus Torvalds
10 */
11
12 #include <linux/config.h>
13 #include <linux/signal.h>
14 #include <linux/sched.h>
15 #include <linux/kernel.h>
16 #include <linux/errno.h>
17 #include <linux/string.h>
18 #include <linux/types.h>
19 #include <linux/ptrace.h>
20 #include <linux/mman.h>
21 #include <linux/mm.h>
22 #include <linux/swap.h>
23 #include <linux/smp.h>
24 #include <linux/init.h>
25 #ifdef CONFIG_BLK_DEV_INITRD
26 #include <linux/blk.h>
27 #endif
28 #include <linux/pagemap.h>
29 #include <linux/bootmem.h>
30
31 #include <asm/processor.h>
32 #include <asm/system.h>
33 #include <asm/uaccess.h>
34 #include <asm/pgtable.h>
35 #include <asm/pgalloc.h>
36 #include <asm/dma.h>
37 #include <asm/lowcore.h>
38 #include <asm/tlb.h>
39
40 mmu_gather_t mmu_gathers[NR_CPUS];
41
42 static unsigned long totalram_pages;
43 extern unsigned long memory_size;
44
45 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));
46 char empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
47
do_check_pgt_cache(int low,int high)48 int do_check_pgt_cache(int low, int high)
49 {
50 int freed = 0;
51 if(pgtable_cache_size > high) {
52 do {
53 if(pgd_quicklist) {
54 free_pgd_slow(get_pgd_fast());
55 freed += 2;
56 }
57 if(pmd_quicklist) {
58 pmd_free_slow(pmd_alloc_one_fast(NULL, 0));
59 freed++;
60 }
61 if(pte_quicklist) {
62 pte_free_slow(pte_alloc_one_fast(NULL, 0));
63 freed++;
64 }
65 } while(pgtable_cache_size > low);
66 }
67 return freed;
68 }
69
diag10(unsigned long addr)70 void diag10(unsigned long addr)
71 {
72 asm volatile ("diag %0,%0,0x10" : : "a" (addr));
73 }
74
show_mem(void)75 void show_mem(void)
76 {
77 int i, total = 0, reserved = 0;
78 int shared = 0, cached = 0;
79
80 printk("Mem-info:\n");
81 show_free_areas();
82 printk("Free swap: %6dkB\n",nr_swap_pages<<(PAGE_SHIFT-10));
83 i = max_mapnr;
84 while (i-- > 0) {
85 total++;
86 if (PageReserved(mem_map+i))
87 reserved++;
88 else if (PageSwapCache(mem_map+i))
89 cached++;
90 else if (page_count(mem_map+i))
91 shared += atomic_read(&mem_map[i].count) - 1;
92 }
93 printk("%d pages of RAM\n",total);
94 printk("%d reserved pages\n",reserved);
95 printk("%d pages shared\n",shared);
96 printk("%d pages swap cached\n",cached);
97 printk("%ld pages in page table cache\n",pgtable_cache_size);
98 show_buffers();
99 }
100
101 /* References to section boundaries */
102
103 extern unsigned long _text;
104 extern unsigned long _etext;
105 extern unsigned long _edata;
106 extern unsigned long __bss_start;
107 extern unsigned long _end;
108
109 extern unsigned long __init_begin;
110 extern unsigned long __init_end;
111
112 /*
113 * paging_init() sets up the page tables - note that the first 4MB are
114 * already mapped by head.S.
115 * paging_init will erase this initial mapping
116 */
117
118 unsigned long last_valid_pfn;
119
paging_init(void)120 void __init paging_init(void)
121 {
122 pgd_t * pg_dir;
123 pte_t * pg_table;
124 pte_t pte;
125 int i;
126 unsigned long tmp;
127 unsigned long address=0;
128 unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE;
129 unsigned long end_mem = (unsigned long) __va(max_low_pfn*PAGE_SIZE);
130 static const int ssm_mask = 0x04000000L;
131
132 /* unmap whole virtual address space */
133
134 pg_dir = swapper_pg_dir;
135
136 for (i=0;i<KERNEL_PGD_PTRS;i++)
137 pmd_clear((pmd_t*)pg_dir++);
138
139 /*
140 * map whole physical memory to virtual memory (identity mapping)
141 */
142
143 pg_dir = swapper_pg_dir;
144
145 while (address < end_mem) {
146 /*
147 * pg_table is physical at this point
148 */
149 pg_table = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
150
151 pg_dir->pgd0 = (_PAGE_TABLE | __pa(pg_table));
152 pg_dir->pgd1 = (_PAGE_TABLE | (__pa(pg_table)+1024));
153 pg_dir->pgd2 = (_PAGE_TABLE | (__pa(pg_table)+2048));
154 pg_dir->pgd3 = (_PAGE_TABLE | (__pa(pg_table)+3072));
155 pg_dir++;
156
157 for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) {
158 pte = mk_pte_phys(address, PAGE_KERNEL);
159 if (address >= end_mem)
160 pte_clear(&pte);
161 set_pte(pg_table, pte);
162 address += PAGE_SIZE;
163 }
164 }
165
166 /* enable virtual mapping in kernel mode */
167 __asm__ __volatile__(" LCTL 1,1,%0\n"
168 " LCTL 7,7,%0\n"
169 " LCTL 13,13,%0\n"
170 " SSM %1"
171 : : "m" (pgdir_k), "m" (ssm_mask));
172
173 local_flush_tlb();
174
175 {
176 unsigned long zones_size[MAX_NR_ZONES] = { 0, 0, 0};
177
178 zones_size[ZONE_DMA] = max_low_pfn;
179 free_area_init(zones_size);
180 }
181
182 return;
183 }
184
mem_init(void)185 void __init mem_init(void)
186 {
187 int codesize, reservedpages, datasize, initsize;
188
189 max_mapnr = num_physpages = max_low_pfn;
190 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
191
192 /* clear the zero-page */
193 memset(empty_zero_page, 0, PAGE_SIZE);
194
195 /* this will put all low memory onto the freelists */
196 totalram_pages += free_all_bootmem();
197
198 reservedpages = 0;
199
200 codesize = (unsigned long) &_etext - (unsigned long) &_text;
201 datasize = (unsigned long) &_edata - (unsigned long) &_etext;
202 initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
203 printk("Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init)\n",
204 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
205 max_mapnr << (PAGE_SHIFT-10),
206 codesize >> 10,
207 reservedpages << (PAGE_SHIFT-10),
208 datasize >>10,
209 initsize >> 10);
210 }
211
free_initmem(void)212 void free_initmem(void)
213 {
214 unsigned long addr;
215
216 addr = (unsigned long)(&__init_begin);
217 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
218 ClearPageReserved(virt_to_page(addr));
219 set_page_count(virt_to_page(addr), 1);
220 free_page(addr);
221 totalram_pages++;
222 }
223 printk (KERN_INFO "Freeing unused kernel memory: %dk freed\n",
224 (&__init_end - &__init_begin) >> 10);
225 }
226
227 #ifdef CONFIG_BLK_DEV_INITRD
free_initrd_mem(unsigned long start,unsigned long end)228 void free_initrd_mem(unsigned long start, unsigned long end)
229 {
230 if (start < end)
231 printk (KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
232 for (; start < end; start += PAGE_SIZE) {
233 ClearPageReserved(virt_to_page(start));
234 set_page_count(virt_to_page(start), 1);
235 free_page(start);
236 totalram_pages++;
237 }
238 }
239 #endif
240
si_meminfo(struct sysinfo * val)241 void si_meminfo(struct sysinfo *val)
242 {
243 val->totalram = totalram_pages;
244 val->sharedram = 0;
245 val->freeram = nr_free_pages();
246 val->bufferram = atomic_read(&buffermem_pages);
247 val->totalhigh = 0;
248 val->freehigh = 0;
249 val->mem_unit = PAGE_SIZE;
250 }
251