Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc
[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 #include <linux/initrd.h>
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 show_mem(void)
46 {
47         int i, total = 0, reserved = 0;
48         int shared = 0, cached = 0;
49         struct page *page;
50
51         printk("Mem-info:\n");
52         show_free_areas();
53         printk("Free swap:       %6ldkB\n", nr_swap_pages << (PAGE_SHIFT - 10));
54         i = max_mapnr;
55         while (i-- > 0) {
56                 if (!pfn_valid(i))
57                         continue;
58                 page = pfn_to_page(i);
59                 total++;
60                 if (PageReserved(page))
61                         reserved++;
62                 else if (PageSwapCache(page))
63                         cached++;
64                 else if (page_count(page))
65                         shared += page_count(page) - 1;
66         }
67         printk("%d pages of RAM\n", total);
68         printk("%d reserved pages\n", reserved);
69         printk("%d pages shared\n", shared);
70         printk("%d pages swap cached\n", cached);
71
72         printk("%lu pages dirty\n", global_page_state(NR_FILE_DIRTY));
73         printk("%lu pages writeback\n", global_page_state(NR_WRITEBACK));
74         printk("%lu pages mapped\n", global_page_state(NR_FILE_MAPPED));
75         printk("%lu pages slab\n",
76                global_page_state(NR_SLAB_RECLAIMABLE) +
77                global_page_state(NR_SLAB_UNRECLAIMABLE));
78         printk("%lu pages pagetables\n", global_page_state(NR_PAGETABLE));
79 }
80
81 static void __init setup_ro_region(void)
82 {
83         pgd_t *pgd;
84         pmd_t *pmd;
85         pte_t *pte;
86         pte_t new_pte;
87         unsigned long address, end;
88
89         address = ((unsigned long)&_stext) & PAGE_MASK;
90         end = PFN_ALIGN((unsigned long)&_eshared);
91
92         for (; address < end; address += PAGE_SIZE) {
93                 pgd = pgd_offset_k(address);
94                 pmd = pmd_offset(pgd, address);
95                 pte = pte_offset_kernel(pmd, address);
96                 new_pte = mk_pte_phys(address, __pgprot(_PAGE_RO));
97                 *pte = new_pte;
98         }
99 }
100
101 /*
102  * paging_init() sets up the page tables
103  */
104 void __init paging_init(void)
105 {
106         pgd_t *pg_dir;
107         int i;
108         unsigned long pgdir_k;
109         static const int ssm_mask = 0x04000000L;
110         unsigned long max_zone_pfns[MAX_NR_ZONES];
111
112         pg_dir = swapper_pg_dir;
113         
114 #ifdef CONFIG_64BIT
115         pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERN_REGION_TABLE;
116         for (i = 0; i < PTRS_PER_PGD; i++)
117                 pgd_clear_kernel(pg_dir + i);
118 #else
119         pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE;
120         for (i = 0; i < PTRS_PER_PGD; i++)
121                 pmd_clear_kernel((pmd_t *)(pg_dir + i));
122 #endif
123         vmem_map_init();
124         setup_ro_region();
125
126         S390_lowcore.kernel_asce = pgdir_k;
127
128         /* enable virtual mapping in kernel mode */
129         __ctl_load(pgdir_k, 1, 1);
130         __ctl_load(pgdir_k, 7, 7);
131         __ctl_load(pgdir_k, 13, 13);
132         __raw_local_irq_ssm(ssm_mask);
133
134         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
135 #ifdef CONFIG_ZONE_DMA
136         max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS);
137 #endif
138         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
139         free_area_init_nodes(max_zone_pfns);
140 }
141
142 void __init mem_init(void)
143 {
144         unsigned long codesize, reservedpages, datasize, initsize;
145
146         max_mapnr = num_physpages = max_low_pfn;
147         high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
148
149         /* clear the zero-page */
150         memset(empty_zero_page, 0, PAGE_SIZE);
151
152         /* this will put all low memory onto the freelists */
153         totalram_pages += free_all_bootmem();
154
155         reservedpages = 0;
156
157         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
158         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
159         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
160         printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n",
161                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
162                 max_mapnr << (PAGE_SHIFT-10),
163                 codesize >> 10,
164                 reservedpages << (PAGE_SHIFT-10),
165                 datasize >>10,
166                 initsize >> 10);
167         printk("Write protected kernel read-only data: %#lx - %#lx\n",
168                (unsigned long)&_stext,
169                PFN_ALIGN((unsigned long)&_eshared) - 1);
170 }
171
172 void free_initmem(void)
173 {
174         unsigned long addr;
175
176         addr = (unsigned long)(&__init_begin);
177         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
178                 ClearPageReserved(virt_to_page(addr));
179                 init_page_count(virt_to_page(addr));
180                 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
181                 free_page(addr);
182                 totalram_pages++;
183         }
184         printk ("Freeing unused kernel memory: %ldk freed\n",
185                 ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10);
186 }
187
188 #ifdef CONFIG_BLK_DEV_INITRD
189 void free_initrd_mem(unsigned long start, unsigned long end)
190 {
191         if (start < end)
192                 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
193         for (; start < end; start += PAGE_SIZE) {
194                 ClearPageReserved(virt_to_page(start));
195                 init_page_count(virt_to_page(start));
196                 free_page(start);
197                 totalram_pages++;
198         }
199 }
200 #endif