tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
40DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
41
42pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));
43char empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
44
45void 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
62void 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
90static 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)&_stext) & PAGE_MASK;
99 end = PFN_ALIGN((unsigned long)&_eshared);
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 *pte = new_pte;
107 }
108}
109
110/*
111 * paging_init() sets up the page tables
112 */
113void __init paging_init(void)
114{
115 pgd_t *pg_dir;
116 int i;
117 unsigned long pgdir_k;
118 static const int ssm_mask = 0x04000000L;
119 unsigned long max_zone_pfns[MAX_NR_ZONES];
120
121 pg_dir = swapper_pg_dir;
122
123#ifdef CONFIG_64BIT
124 pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERN_REGION_TABLE;
125 for (i = 0; i < PTRS_PER_PGD; i++)
126 pgd_clear_kernel(pg_dir + i);
127#else
128 pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE;
129 for (i = 0; i < PTRS_PER_PGD; i++)
130 pmd_clear_kernel((pmd_t *)(pg_dir + i));
131#endif
132 vmem_map_init();
133 setup_ro_region();
134
135 S390_lowcore.kernel_asce = pgdir_k;
136
137 /* enable virtual mapping in kernel mode */
138 __ctl_load(pgdir_k, 1, 1);
139 __ctl_load(pgdir_k, 7, 7);
140 __ctl_load(pgdir_k, 13, 13);
141 __raw_local_irq_ssm(ssm_mask);
142
143 memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
144#ifdef CONFIG_ZONE_DMA
145 max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS);
146#endif
147 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
148 free_area_init_nodes(max_zone_pfns);
149}
150
151void __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)&_stext,
178 PFN_ALIGN((unsigned long)&_eshared) - 1);
179}
180
181void free_initmem(void)
182{
183 unsigned long addr;
184
185 addr = (unsigned long)(&__init_begin);
186 for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
187 ClearPageReserved(virt_to_page(addr));
188 init_page_count(virt_to_page(addr));
189 memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
190 free_page(addr);
191 totalram_pages++;
192 }
193 printk ("Freeing unused kernel memory: %ldk freed\n",
194 ((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10);
195}
196
197#ifdef CONFIG_BLK_DEV_INITRD
198void free_initrd_mem(unsigned long start, unsigned long end)
199{
200 if (start < end)
201 printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
202 for (; start < end; start += PAGE_SIZE) {
203 ClearPageReserved(virt_to_page(start));
204 init_page_count(virt_to_page(start));
205 free_page(start);
206 totalram_pages++;
207 }
208}
209#endif