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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/um/kernel/mem.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/um/kernel/mem.c')
-rw-r--r--arch/um/kernel/mem.c359
1 files changed, 359 insertions, 0 deletions
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
new file mode 100644
index 000000000000..f156661781cb
--- /dev/null
+++ b/arch/um/kernel/mem.c
@@ -0,0 +1,359 @@
1/*
2 * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
3 * Licensed under the GPL
4 */
5
6#include "linux/stddef.h"
7#include "linux/kernel.h"
8#include "linux/mm.h"
9#include "linux/bootmem.h"
10#include "linux/swap.h"
11#include "linux/highmem.h"
12#include "linux/gfp.h"
13#include "asm/page.h"
14#include "asm/fixmap.h"
15#include "asm/pgalloc.h"
16#include "user_util.h"
17#include "kern_util.h"
18#include "kern.h"
19#include "mem_user.h"
20#include "uml_uaccess.h"
21#include "os.h"
22
23extern char __binary_start;
24
25/* Changed during early boot */
26unsigned long *empty_zero_page = NULL;
27unsigned long *empty_bad_page = NULL;
28pgd_t swapper_pg_dir[PTRS_PER_PGD];
29unsigned long highmem;
30int kmalloc_ok = 0;
31
32static unsigned long brk_end;
33
34void unmap_physmem(void)
35{
36 os_unmap_memory((void *) brk_end, uml_reserved - brk_end);
37}
38
39static void map_cb(void *unused)
40{
41 map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
42}
43
44#ifdef CONFIG_HIGHMEM
45static void setup_highmem(unsigned long highmem_start,
46 unsigned long highmem_len)
47{
48 struct page *page;
49 unsigned long highmem_pfn;
50 int i;
51
52 highmem_pfn = __pa(highmem_start) >> PAGE_SHIFT;
53 for(i = 0; i < highmem_len >> PAGE_SHIFT; i++){
54 page = &mem_map[highmem_pfn + i];
55 ClearPageReserved(page);
56 set_bit(PG_highmem, &page->flags);
57 set_page_count(page, 1);
58 __free_page(page);
59 }
60}
61#endif
62
63void mem_init(void)
64{
65 unsigned long start;
66
67 max_low_pfn = (high_physmem - uml_physmem) >> PAGE_SHIFT;
68
69 /* clear the zero-page */
70 memset((void *) empty_zero_page, 0, PAGE_SIZE);
71
72 /* Map in the area just after the brk now that kmalloc is about
73 * to be turned on.
74 */
75 brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
76 map_cb(NULL);
77 initial_thread_cb(map_cb, NULL);
78 free_bootmem(__pa(brk_end), uml_reserved - brk_end);
79 uml_reserved = brk_end;
80
81 /* Fill in any hole at the start of the binary */
82 start = (unsigned long) &__binary_start & PAGE_MASK;
83 if(uml_physmem != start){
84 map_memory(uml_physmem, __pa(uml_physmem), start - uml_physmem,
85 1, 1, 0);
86 }
87
88 /* this will put all low memory onto the freelists */
89 totalram_pages = free_all_bootmem();
90 totalhigh_pages = highmem >> PAGE_SHIFT;
91 totalram_pages += totalhigh_pages;
92 num_physpages = totalram_pages;
93 max_pfn = totalram_pages;
94 printk(KERN_INFO "Memory: %luk available\n",
95 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10));
96 kmalloc_ok = 1;
97
98#ifdef CONFIG_HIGHMEM
99 setup_highmem(end_iomem, highmem);
100#endif
101}
102
103static void __init fixrange_init(unsigned long start, unsigned long end,
104 pgd_t *pgd_base)
105{
106 pgd_t *pgd;
107 pmd_t *pmd;
108 pte_t *pte;
109 int i, j;
110 unsigned long vaddr;
111
112 vaddr = start;
113 i = pgd_index(vaddr);
114 j = pmd_index(vaddr);
115 pgd = pgd_base + i;
116
117 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
118 pmd = (pmd_t *)pgd;
119 for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) {
120 if (pmd_none(*pmd)) {
121 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
122 set_pmd(pmd, __pmd(_KERNPG_TABLE +
123 (unsigned long) __pa(pte)));
124 if (pte != pte_offset_kernel(pmd, 0))
125 BUG();
126 }
127 vaddr += PMD_SIZE;
128 }
129 j = 0;
130 }
131}
132
133#ifdef CONFIG_HIGHMEM
134pte_t *kmap_pte;
135pgprot_t kmap_prot;
136
137#define kmap_get_fixmap_pte(vaddr) \
138 pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)),\
139 (vaddr)), (vaddr))
140
141static void __init kmap_init(void)
142{
143 unsigned long kmap_vstart;
144
145 /* cache the first kmap pte */
146 kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
147 kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
148
149 kmap_prot = PAGE_KERNEL;
150}
151
152static void init_highmem(void)
153{
154 pgd_t *pgd;
155 pud_t *pud;
156 pmd_t *pmd;
157 pte_t *pte;
158 unsigned long vaddr;
159
160 /*
161 * Permanent kmaps:
162 */
163 vaddr = PKMAP_BASE;
164 fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, swapper_pg_dir);
165
166 pgd = swapper_pg_dir + pgd_index(vaddr);
167 pud = pud_offset(pgd, vaddr);
168 pmd = pmd_offset(pud, vaddr);
169 pte = pte_offset_kernel(pmd, vaddr);
170 pkmap_page_table = pte;
171
172 kmap_init();
173}
174#endif /* CONFIG_HIGHMEM */
175
176static void __init fixaddr_user_init( void)
177{
178#if CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
179 long size = FIXADDR_USER_END - FIXADDR_USER_START;
180 pgd_t *pgd;
181 pud_t *pud;
182 pmd_t *pmd;
183 pte_t *pte;
184 unsigned long paddr, vaddr = FIXADDR_USER_START;
185
186 if ( ! size )
187 return;
188
189 fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir);
190 paddr = (unsigned long)alloc_bootmem_low_pages( size);
191 memcpy( (void *)paddr, (void *)FIXADDR_USER_START, size);
192 paddr = __pa(paddr);
193 for ( ; size > 0; size-=PAGE_SIZE, vaddr+=PAGE_SIZE, paddr+=PAGE_SIZE){
194 pgd = swapper_pg_dir + pgd_index(vaddr);
195 pud = pud_offset(pgd, vaddr);
196 pmd = pmd_offset(pud, vaddr);
197 pte = pte_offset_kernel(pmd, vaddr);
198 pte_set_val( (*pte), paddr, PAGE_READONLY);
199 }
200#endif
201}
202
203void paging_init(void)
204{
205 unsigned long zones_size[MAX_NR_ZONES], vaddr;
206 int i;
207
208 empty_zero_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
209 empty_bad_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
210 for(i=0;i<sizeof(zones_size)/sizeof(zones_size[0]);i++)
211 zones_size[i] = 0;
212 zones_size[0] = (end_iomem >> PAGE_SHIFT) - (uml_physmem >> PAGE_SHIFT);
213 zones_size[2] = highmem >> PAGE_SHIFT;
214 free_area_init(zones_size);
215
216 /*
217 * Fixed mappings, only the page table structure has to be
218 * created - mappings will be set by set_fixmap():
219 */
220 vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
221 fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
222
223 fixaddr_user_init();
224
225#ifdef CONFIG_HIGHMEM
226 init_highmem();
227#endif
228}
229
230struct page *arch_validate(struct page *page, int mask, int order)
231{
232 unsigned long addr, zero = 0;
233 int i;
234
235 again:
236 if(page == NULL) return(page);
237 if(PageHighMem(page)) return(page);
238
239 addr = (unsigned long) page_address(page);
240 for(i = 0; i < (1 << order); i++){
241 current->thread.fault_addr = (void *) addr;
242 if(__do_copy_to_user((void __user *) addr, &zero,
243 sizeof(zero),
244 &current->thread.fault_addr,
245 &current->thread.fault_catcher)){
246 if(!(mask & __GFP_WAIT)) return(NULL);
247 else break;
248 }
249 addr += PAGE_SIZE;
250 }
251
252 if(i == (1 << order)) return(page);
253 page = alloc_pages(mask, order);
254 goto again;
255}
256
257/* This can't do anything because nothing in the kernel image can be freed
258 * since it's not in kernel physical memory.
259 */
260
261void free_initmem(void)
262{
263}
264
265#ifdef CONFIG_BLK_DEV_INITRD
266
267void free_initrd_mem(unsigned long start, unsigned long end)
268{
269 if (start < end)
270 printk ("Freeing initrd memory: %ldk freed\n",
271 (end - start) >> 10);
272 for (; start < end; start += PAGE_SIZE) {
273 ClearPageReserved(virt_to_page(start));
274 set_page_count(virt_to_page(start), 1);
275 free_page(start);
276 totalram_pages++;
277 }
278}
279
280#endif
281
282void show_mem(void)
283{
284 int pfn, total = 0, reserved = 0;
285 int shared = 0, cached = 0;
286 int highmem = 0;
287 struct page *page;
288
289 printk("Mem-info:\n");
290 show_free_areas();
291 printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
292 pfn = max_mapnr;
293 while(pfn-- > 0) {
294 page = pfn_to_page(pfn);
295 total++;
296 if(PageHighMem(page))
297 highmem++;
298 if(PageReserved(page))
299 reserved++;
300 else if(PageSwapCache(page))
301 cached++;
302 else if(page_count(page))
303 shared += page_count(page) - 1;
304 }
305 printk("%d pages of RAM\n", total);
306 printk("%d pages of HIGHMEM\n", highmem);
307 printk("%d reserved pages\n", reserved);
308 printk("%d pages shared\n", shared);
309 printk("%d pages swap cached\n", cached);
310}
311
312/*
313 * Allocate and free page tables.
314 */
315
316pgd_t *pgd_alloc(struct mm_struct *mm)
317{
318 pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
319
320 if (pgd) {
321 memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
322 memcpy(pgd + USER_PTRS_PER_PGD,
323 swapper_pg_dir + USER_PTRS_PER_PGD,
324 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
325 }
326 return pgd;
327}
328
329void pgd_free(pgd_t *pgd)
330{
331 free_page((unsigned long) pgd);
332}
333
334pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
335{
336 pte_t *pte;
337
338 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
339 return pte;
340}
341
342struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
343{
344 struct page *pte;
345
346 pte = alloc_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
347 return pte;
348}
349
350/*
351 * Overrides for Emacs so that we follow Linus's tabbing style.
352 * Emacs will notice this stuff at the end of the file and automatically
353 * adjust the settings for this buffer only. This must remain at the end
354 * of the file.
355 * ---------------------------------------------------------------------------
356 * Local variables:
357 * c-file-style: "linux"
358 * End:
359 */