Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6
[linux-2.6] / arch / s390 / mm / init.c
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/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>
20 #include <linux/mm.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>
27 #include <linux/poison.h>
28
29 #include <asm/processor.h>
30 #include <asm/system.h>
31 #include <asm/uaccess.h>
32 #include <asm/pgtable.h>
33 #include <asm/pgalloc.h>
34 #include <asm/dma.h>
35 #include <asm/lowcore.h>
36 #include <asm/tlb.h>
37 #include <asm/tlbflush.h>
38 #include <asm/sections.h>
39
40 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
41
42 pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));
43 char  empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
44
45 void diag10(unsigned long addr)
46 {
47         if (addr >= 0x7ff00000)
48                 return;
49         asm volatile(
50 #ifdef CONFIG_64BIT
51                 "       sam31\n"
52                 "       diag    %0,%0,0x10\n"
53                 "0:     sam64\n"
54 #else
55                 "       diag    %0,%0,0x10\n"
56                 "0:\n"
57 #endif
58                 EX_TABLE(0b,0b)
59                 : : "a" (addr));
60 }
61
62 void show_mem(void)
63 {
64         int i, total = 0, reserved = 0;
65         int shared = 0, cached = 0;
66         struct page *page;
67
68         printk("Mem-info:\n");
69         show_free_areas();
70         printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
71         i = max_mapnr;
72         while (i-- > 0) {
73                 if (!pfn_valid(i))
74                         continue;
75                 page = pfn_to_page(i);
76                 total++;
77                 if (PageReserved(page))
78                         reserved++;
79                 else if (PageSwapCache(page))
80                         cached++;
81                 else if (page_count(page))
82                         shared += page_count(page) - 1;
83         }
84         printk("%d pages of RAM\n",total);
85         printk("%d reserved pages\n",reserved);
86         printk("%d pages shared\n",shared);
87         printk("%d pages swap cached\n",cached);
88 }
89
90 static void __init setup_ro_region(void)
91 {
92         pgd_t *pgd;
93         pmd_t *pmd;
94         pte_t *pte;
95         pte_t new_pte;
96         unsigned long address, end;
97
98         address = ((unsigned long)&__start_rodata) & PAGE_MASK;
99         end = PFN_ALIGN((unsigned long)&__end_rodata);
100
101         for (; address < end; address += PAGE_SIZE) {
102                 pgd = pgd_offset_k(address);
103                 pmd = pmd_offset(pgd, address);
104                 pte = pte_offset_kernel(pmd, address);
105                 new_pte = mk_pte_phys(address, __pgprot(_PAGE_RO));
106                 set_pte(pte, new_pte);
107         }
108 }
109
110 extern void vmem_map_init(void);
111
112 /*
113  * paging_init() sets up the page tables
114  */
115 void __init paging_init(void)
116 {
117         pgd_t *pg_dir;
118         int i;
119         unsigned long pgdir_k;
120         static const int ssm_mask = 0x04000000L;
121         unsigned long max_zone_pfns[MAX_NR_ZONES];
122
123         pg_dir = swapper_pg_dir;
124         
125 #ifdef CONFIG_64BIT
126         pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERN_REGION_TABLE;
127         for (i = 0; i < PTRS_PER_PGD; i++)
128                 pgd_clear(pg_dir + i);
129 #else
130         pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE;
131         for (i = 0; i < PTRS_PER_PGD; i++)
132                 pmd_clear((pmd_t *)(pg_dir + i));
133 #endif
134         vmem_map_init();
135         setup_ro_region();
136
137         S390_lowcore.kernel_asce = pgdir_k;
138
139         /* enable virtual mapping in kernel mode */
140         __ctl_load(pgdir_k, 1, 1);
141         __ctl_load(pgdir_k, 7, 7);
142         __ctl_load(pgdir_k, 13, 13);
143         __raw_local_irq_ssm(ssm_mask);
144
145         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
146         max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS);
147         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
148         free_area_init_nodes(max_zone_pfns);
149 }
150
151 void __init mem_init(void)
152 {
153         unsigned long codesize, reservedpages, datasize, initsize;
154
155         max_mapnr = num_physpages = max_low_pfn;
156         high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
157
158         /* clear the zero-page */
159         memset(empty_zero_page, 0, PAGE_SIZE);
160
161         /* this will put all low memory onto the freelists */
162         totalram_pages += free_all_bootmem();
163
164         reservedpages = 0;
165
166         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
167         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
168         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
169         printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n",
170                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
171                 max_mapnr << (PAGE_SHIFT-10),
172                 codesize >> 10,
173                 reservedpages << (PAGE_SHIFT-10),
174                 datasize >>10,
175                 initsize >> 10);
176         printk("Write protected kernel read-only data: %#lx - %#lx\n",
177                (unsigned long)&__start_rodata,
178                PFN_ALIGN((unsigned long)&__end_rodata) - 1);
179         printk("Virtual memmap size: %ldk\n",
180                (max_pfn * sizeof(struct page)) >> 10);
181 }
182
183 void free_initmem(void)
184 {
185         unsigned long addr;
186
187         addr = (unsigned long)(&__init_begin);
188         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
189                 ClearPageReserved(virt_to_page(addr));
190                 init_page_count(virt_to_page(addr));
191                 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
192                 free_page(addr);
193                 totalram_pages++;
194         }
195         printk ("Freeing unused kernel memory: %ldk freed\n",
196                 ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10);
197 }
198
199 #ifdef CONFIG_BLK_DEV_INITRD
200 void free_initrd_mem(unsigned long start, unsigned long end)
201 {
202         if (start < end)
203                 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
204         for (; start < end; start += PAGE_SIZE) {
205                 ClearPageReserved(virt_to_page(start));
206                 init_page_count(virt_to_page(start));
207                 free_page(start);
208                 totalram_pages++;
209         }
210 }
211 #endif