]>
git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - arch/powerpc/mm/pgtable_32.c
db0d35e0169bb559f8fed9b27378733d1e3f8d4a
2 * This file contains the routines setting up the linux page tables.
5 * Derived from arch/ppc/mm/init.c:
6 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
8 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
9 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
10 * Copyright (C) 1996 Paul Mackerras
12 * Derived from "arch/i386/mm/init.c"
13 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version.
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/types.h>
26 #include <linux/vmalloc.h>
27 #include <linux/init.h>
28 #include <linux/highmem.h>
29 #include <linux/memblock.h>
30 #include <linux/slab.h>
32 #include <asm/pgtable.h>
33 #include <asm/pgalloc.h>
34 #include <asm/fixmap.h>
36 #include <asm/setup.h>
40 unsigned long ioremap_base
;
41 unsigned long ioremap_bot
;
42 EXPORT_SYMBOL(ioremap_bot
); /* aka VMALLOC_END */
44 extern char etext
[], _stext
[];
46 #define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT)
48 #ifndef CONFIG_PPC_4K_PAGES
49 static struct kmem_cache
*pgtable_cache
;
51 void pgtable_cache_init(void)
53 pgtable_cache
= kmem_cache_create("PGDIR cache", 1 << PGDIR_ORDER
,
54 1 << PGDIR_ORDER
, 0, NULL
);
55 if (pgtable_cache
== NULL
)
56 panic("Couldn't allocate pgtable caches");
60 pgd_t
*pgd_alloc(struct mm_struct
*mm
)
64 /* pgdir take page or two with 4K pages and a page fraction otherwise */
65 #ifndef CONFIG_PPC_4K_PAGES
66 ret
= kmem_cache_alloc(pgtable_cache
, GFP_KERNEL
| __GFP_ZERO
);
68 ret
= (pgd_t
*)__get_free_pages(GFP_KERNEL
|__GFP_ZERO
,
69 PGDIR_ORDER
- PAGE_SHIFT
);
74 void pgd_free(struct mm_struct
*mm
, pgd_t
*pgd
)
76 #ifndef CONFIG_PPC_4K_PAGES
77 kmem_cache_free(pgtable_cache
, (void *)pgd
);
79 free_pages((unsigned long)pgd
, PGDIR_ORDER
- PAGE_SHIFT
);
83 __init_refok pte_t
*pte_alloc_one_kernel(struct mm_struct
*mm
, unsigned long address
)
87 if (slab_is_available()) {
88 pte
= (pte_t
*)__get_free_page(GFP_KERNEL
|__GFP_REPEAT
|__GFP_ZERO
);
90 pte
= __va(memblock_alloc(PAGE_SIZE
, PAGE_SIZE
));
97 pgtable_t
pte_alloc_one(struct mm_struct
*mm
, unsigned long address
)
101 gfp_t flags
= GFP_KERNEL
| __GFP_REPEAT
| __GFP_ZERO
;
103 ptepage
= alloc_pages(flags
, 0);
106 if (!pgtable_page_ctor(ptepage
)) {
107 __free_page(ptepage
);
114 ioremap(phys_addr_t addr
, unsigned long size
)
116 return __ioremap_caller(addr
, size
, _PAGE_NO_CACHE
| _PAGE_GUARDED
,
117 __builtin_return_address(0));
119 EXPORT_SYMBOL(ioremap
);
122 ioremap_wc(phys_addr_t addr
, unsigned long size
)
124 return __ioremap_caller(addr
, size
, _PAGE_NO_CACHE
,
125 __builtin_return_address(0));
127 EXPORT_SYMBOL(ioremap_wc
);
130 ioremap_prot(phys_addr_t addr
, unsigned long size
, unsigned long flags
)
132 /* writeable implies dirty for kernel addresses */
133 if ((flags
& (_PAGE_RW
| _PAGE_RO
)) != _PAGE_RO
)
134 flags
|= _PAGE_DIRTY
| _PAGE_HWWRITE
;
136 /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
137 flags
&= ~(_PAGE_USER
| _PAGE_EXEC
);
140 /* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
141 * which means that we just cleared supervisor access... oops ;-) This
144 flags
|= _PAGE_BAP_SR
;
147 return __ioremap_caller(addr
, size
, flags
, __builtin_return_address(0));
149 EXPORT_SYMBOL(ioremap_prot
);
152 __ioremap(phys_addr_t addr
, unsigned long size
, unsigned long flags
)
154 return __ioremap_caller(addr
, size
, flags
, __builtin_return_address(0));
158 __ioremap_caller(phys_addr_t addr
, unsigned long size
, unsigned long flags
,
165 /* Make sure we have the base flags */
166 if ((flags
& _PAGE_PRESENT
) == 0)
167 flags
|= pgprot_val(PAGE_KERNEL
);
169 /* Non-cacheable page cannot be coherent */
170 if (flags
& _PAGE_NO_CACHE
)
171 flags
&= ~_PAGE_COHERENT
;
174 * Choose an address to map it to.
175 * Once the vmalloc system is running, we use it.
176 * Before then, we use space going down from ioremap_base
177 * (ioremap_bot records where we're up to).
179 p
= addr
& PAGE_MASK
;
180 size
= PAGE_ALIGN(addr
+ size
) - p
;
183 * If the address lies within the first 16 MB, assume it's in ISA
186 if (p
< 16*1024*1024)
189 #ifndef CONFIG_CRASH_DUMP
191 * Don't allow anybody to remap normal RAM that we're using.
192 * mem_init() sets high_memory so only do the check after that.
194 if (slab_is_available() && (p
< virt_to_phys(high_memory
)) &&
195 !(__allow_ioremap_reserved
&& memblock_is_region_reserved(p
, size
))) {
196 printk("__ioremap(): phys addr 0x%llx is RAM lr %ps\n",
197 (unsigned long long)p
, __builtin_return_address(0));
206 * Is it already mapped? Perhaps overlapped by a previous
209 v
= p_block_mapped(p
);
213 if (slab_is_available()) {
214 struct vm_struct
*area
;
215 area
= get_vm_area_caller(size
, VM_IOREMAP
, caller
);
219 v
= (unsigned long) area
->addr
;
221 v
= (ioremap_bot
-= size
);
225 * Should check if it is a candidate for a BAT mapping
229 for (i
= 0; i
< size
&& err
== 0; i
+= PAGE_SIZE
)
230 err
= map_page(v
+i
, p
+i
, flags
);
232 if (slab_is_available())
238 return (void __iomem
*) (v
+ ((unsigned long)addr
& ~PAGE_MASK
));
240 EXPORT_SYMBOL(__ioremap
);
242 void iounmap(volatile void __iomem
*addr
)
245 * If mapped by BATs then there is nothing to do.
246 * Calling vfree() generates a benign warning.
248 if (v_block_mapped((unsigned long)addr
))
251 if (addr
> high_memory
&& (unsigned long) addr
< ioremap_bot
)
252 vunmap((void *) (PAGE_MASK
& (unsigned long)addr
));
254 EXPORT_SYMBOL(iounmap
);
256 int map_page(unsigned long va
, phys_addr_t pa
, int flags
)
262 /* Use upper 10 bits of VA to index the first level map */
263 pd
= pmd_offset(pud_offset(pgd_offset_k(va
), va
), va
);
264 /* Use middle 10 bits of VA to index the second-level map */
265 pg
= pte_alloc_kernel(pd
, va
);
268 /* The PTE should never be already set nor present in the
271 BUG_ON((pte_val(*pg
) & (_PAGE_PRESENT
| _PAGE_HASHPTE
)) &&
273 set_pte_at(&init_mm
, va
, pg
, pfn_pte(pa
>> PAGE_SHIFT
,
281 * Map in a chunk of physical memory starting at start.
283 void __init
__mapin_ram_chunk(unsigned long offset
, unsigned long top
)
285 unsigned long v
, s
, f
;
291 p
= memstart_addr
+ s
;
292 for (; s
< top
; s
+= PAGE_SIZE
) {
293 ktext
= ((char *) v
>= _stext
&& (char *) v
< etext
);
294 f
= ktext
? pgprot_val(PAGE_KERNEL_TEXT
) : pgprot_val(PAGE_KERNEL
);
296 #ifdef CONFIG_PPC_STD_MMU_32
298 hash_preload(&init_mm
, v
, 0, 0x300);
305 void __init
mapin_ram(void)
307 unsigned long s
, top
;
311 s
= mmu_mapin_ram(top
);
312 __mapin_ram_chunk(s
, top
);
314 if (!wii_hole_size
) {
315 s
= mmu_mapin_ram(total_lowmem
);
316 __mapin_ram_chunk(s
, total_lowmem
);
318 top
= wii_hole_start
;
319 s
= mmu_mapin_ram(top
);
320 __mapin_ram_chunk(s
, top
);
322 top
= memblock_end_of_DRAM();
323 s
= wii_mmu_mapin_mem2(top
);
324 __mapin_ram_chunk(s
, top
);
329 /* Scan the real Linux page tables and return a PTE pointer for
330 * a virtual address in a context.
331 * Returns true (1) if PTE was found, zero otherwise. The pointer to
332 * the PTE pointer is unmodified if PTE is not found.
335 get_pteptr(struct mm_struct
*mm
, unsigned long addr
, pte_t
**ptep
, pmd_t
**pmdp
)
343 pgd
= pgd_offset(mm
, addr
& PAGE_MASK
);
345 pud
= pud_offset(pgd
, addr
& PAGE_MASK
);
346 if (pud
&& pud_present(*pud
)) {
347 pmd
= pmd_offset(pud
, addr
& PAGE_MASK
);
348 if (pmd_present(*pmd
)) {
349 pte
= pte_offset_map(pmd
, addr
& PAGE_MASK
);
355 /* XXX caller needs to do pte_unmap, yuck */
363 #ifdef CONFIG_DEBUG_PAGEALLOC
365 static int __change_page_attr(struct page
*page
, pgprot_t prot
)
369 unsigned long address
;
371 BUG_ON(PageHighMem(page
));
372 address
= (unsigned long)page_address(page
);
374 if (v_block_mapped(address
))
376 if (!get_pteptr(&init_mm
, address
, &kpte
, &kpmd
))
378 __set_pte_at(&init_mm
, address
, kpte
, mk_pte(page
, prot
), 0);
380 flush_tlb_page(NULL
, address
);
387 * Change the page attributes of an page in the linear mapping.
389 * THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY
391 static int change_page_attr(struct page
*page
, int numpages
, pgprot_t prot
)
396 local_irq_save(flags
);
397 for (i
= 0; i
< numpages
; i
++, page
++) {
398 err
= __change_page_attr(page
, prot
);
402 local_irq_restore(flags
);
407 void __kernel_map_pages(struct page
*page
, int numpages
, int enable
)
409 if (PageHighMem(page
))
412 change_page_attr(page
, numpages
, enable
? PAGE_KERNEL
: __pgprot(0));
414 #endif /* CONFIG_DEBUG_PAGEALLOC */
418 void __set_fixmap (enum fixed_addresses idx
, phys_addr_t phys
, pgprot_t flags
)
420 unsigned long address
= __fix_to_virt(idx
);
422 if (idx
>= __end_of_fixed_addresses
) {
427 map_page(address
, phys
, pgprot_val(flags
));
431 void __this_fixmap_does_not_exist(void)