1 /*
2 * This file contains ioremap and related functions for 64-bit machines.
3 *
4 * Derived from arch/ppc64/mm/init.c
5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 *
7 * Modifications by Paul Mackerras (PowerMac) (paulus@samba.org)
8 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
9 * Copyright (C) 1996 Paul Mackerras
10 *
11 * Derived from "arch/i386/mm/init.c"
12 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
13 *
14 * Dave Engebretsen <engebret@us.ibm.com>
15 * Rework for PPC64 port.
16 *
17 * This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License
19 * as published by the Free Software Foundation; either version
20 * 2 of the License, or (at your option) any later version.
21 *
22 */
23
24 #include <linux/signal.h>
25 #include <linux/sched.h>
26 #include <linux/kernel.h>
27 #include <linux/errno.h>
28 #include <linux/string.h>
29 #include <linux/export.h>
30 #include <linux/types.h>
31 #include <linux/mman.h>
32 #include <linux/mm.h>
33 #include <linux/swap.h>
34 #include <linux/stddef.h>
35 #include <linux/vmalloc.h>
36 #include <linux/slab.h>
37 #include <linux/hugetlb.h>
38
39 #include <asm/pgalloc.h>
40 #include <asm/page.h>
41 #include <asm/prom.h>
42 #include <asm/io.h>
43 #include <asm/mmu_context.h>
44 #include <asm/pgtable.h>
45 #include <asm/mmu.h>
46 #include <asm/smp.h>
47 #include <asm/machdep.h>
48 #include <asm/tlb.h>
49 #include <asm/processor.h>
50 #include <asm/cputable.h>
51 #include <asm/sections.h>
52 #include <asm/firmware.h>
53 #include <asm/dma.h>
54
55 #include "mmu_decl.h"
56
57
58 #ifdef CONFIG_PPC_BOOK3S_64
59 /*
60 * partition table and process table for ISA 3.0
61 */
62 struct prtb_entry *process_tb;
63 struct patb_entry *partition_tb;
64 /*
65 * page table size
66 */
67 unsigned long __pte_index_size;
68 EXPORT_SYMBOL(__pte_index_size);
69 unsigned long __pmd_index_size;
70 EXPORT_SYMBOL(__pmd_index_size);
71 unsigned long __pud_index_size;
72 EXPORT_SYMBOL(__pud_index_size);
73 unsigned long __pgd_index_size;
74 EXPORT_SYMBOL(__pgd_index_size);
75 unsigned long __pud_cache_index;
76 EXPORT_SYMBOL(__pud_cache_index);
77 unsigned long __pte_table_size;
78 EXPORT_SYMBOL(__pte_table_size);
79 unsigned long __pmd_table_size;
80 EXPORT_SYMBOL(__pmd_table_size);
81 unsigned long __pud_table_size;
82 EXPORT_SYMBOL(__pud_table_size);
83 unsigned long __pgd_table_size;
84 EXPORT_SYMBOL(__pgd_table_size);
85 unsigned long __pmd_val_bits;
86 EXPORT_SYMBOL(__pmd_val_bits);
87 unsigned long __pud_val_bits;
88 EXPORT_SYMBOL(__pud_val_bits);
89 unsigned long __pgd_val_bits;
90 EXPORT_SYMBOL(__pgd_val_bits);
91 unsigned long __kernel_virt_start;
92 EXPORT_SYMBOL(__kernel_virt_start);
93 unsigned long __kernel_virt_size;
94 EXPORT_SYMBOL(__kernel_virt_size);
95 unsigned long __vmalloc_start;
96 EXPORT_SYMBOL(__vmalloc_start);
97 unsigned long __vmalloc_end;
98 EXPORT_SYMBOL(__vmalloc_end);
99 unsigned long __kernel_io_start;
100 EXPORT_SYMBOL(__kernel_io_start);
101 struct page *vmemmap;
102 EXPORT_SYMBOL(vmemmap);
103 unsigned long __pte_frag_nr;
104 EXPORT_SYMBOL(__pte_frag_nr);
105 unsigned long __pte_frag_size_shift;
106 EXPORT_SYMBOL(__pte_frag_size_shift);
107 unsigned long ioremap_bot;
108 #else /* !CONFIG_PPC_BOOK3S_64 */
109 unsigned long ioremap_bot = IOREMAP_BASE;
110 #endif
111
112 /**
113 * __ioremap_at - Low level function to establish the page tables
114 * for an IO mapping
115 */
__ioremap_at(phys_addr_t pa,void * ea,unsigned long size,unsigned long flags)116 void __iomem * __ioremap_at(phys_addr_t pa, void *ea, unsigned long size,
117 unsigned long flags)
118 {
119 unsigned long i;
120
121 /* Make sure we have the base flags */
122 if ((flags & _PAGE_PRESENT) == 0)
123 flags |= pgprot_val(PAGE_KERNEL);
124
125 /* We don't support the 4K PFN hack with ioremap */
126 if (flags & H_PAGE_4K_PFN)
127 return NULL;
128
129 WARN_ON(pa & ~PAGE_MASK);
130 WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
131 WARN_ON(size & ~PAGE_MASK);
132
133 for (i = 0; i < size; i += PAGE_SIZE)
134 if (map_kernel_page((unsigned long)ea+i, pa+i, flags))
135 return NULL;
136
137 return (void __iomem *)ea;
138 }
139
140 /**
141 * __iounmap_from - Low level function to tear down the page tables
142 * for an IO mapping. This is used for mappings that
143 * are manipulated manually, like partial unmapping of
144 * PCI IOs or ISA space.
145 */
__iounmap_at(void * ea,unsigned long size)146 void __iounmap_at(void *ea, unsigned long size)
147 {
148 WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
149 WARN_ON(size & ~PAGE_MASK);
150
151 unmap_kernel_range((unsigned long)ea, size);
152 }
153
__ioremap_caller(phys_addr_t addr,unsigned long size,unsigned long flags,void * caller)154 void __iomem * __ioremap_caller(phys_addr_t addr, unsigned long size,
155 unsigned long flags, void *caller)
156 {
157 phys_addr_t paligned;
158 void __iomem *ret;
159
160 /*
161 * Choose an address to map it to.
162 * Once the imalloc system is running, we use it.
163 * Before that, we map using addresses going
164 * up from ioremap_bot. imalloc will use
165 * the addresses from ioremap_bot through
166 * IMALLOC_END
167 *
168 */
169 paligned = addr & PAGE_MASK;
170 size = PAGE_ALIGN(addr + size) - paligned;
171
172 if ((size == 0) || (paligned == 0))
173 return NULL;
174
175 if (slab_is_available()) {
176 struct vm_struct *area;
177
178 area = __get_vm_area_caller(size, VM_IOREMAP,
179 ioremap_bot, IOREMAP_END,
180 caller);
181 if (area == NULL)
182 return NULL;
183
184 area->phys_addr = paligned;
185 ret = __ioremap_at(paligned, area->addr, size, flags);
186 if (!ret)
187 vunmap(area->addr);
188 } else {
189 ret = __ioremap_at(paligned, (void *)ioremap_bot, size, flags);
190 if (ret)
191 ioremap_bot += size;
192 }
193
194 if (ret)
195 ret += addr & ~PAGE_MASK;
196 return ret;
197 }
198
__ioremap(phys_addr_t addr,unsigned long size,unsigned long flags)199 void __iomem * __ioremap(phys_addr_t addr, unsigned long size,
200 unsigned long flags)
201 {
202 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
203 }
204
ioremap(phys_addr_t addr,unsigned long size)205 void __iomem * ioremap(phys_addr_t addr, unsigned long size)
206 {
207 unsigned long flags = pgprot_val(pgprot_noncached(__pgprot(0)));
208 void *caller = __builtin_return_address(0);
209
210 if (ppc_md.ioremap)
211 return ppc_md.ioremap(addr, size, flags, caller);
212 return __ioremap_caller(addr, size, flags, caller);
213 }
214
ioremap_wc(phys_addr_t addr,unsigned long size)215 void __iomem * ioremap_wc(phys_addr_t addr, unsigned long size)
216 {
217 unsigned long flags = pgprot_val(pgprot_noncached_wc(__pgprot(0)));
218 void *caller = __builtin_return_address(0);
219
220 if (ppc_md.ioremap)
221 return ppc_md.ioremap(addr, size, flags, caller);
222 return __ioremap_caller(addr, size, flags, caller);
223 }
224
ioremap_prot(phys_addr_t addr,unsigned long size,unsigned long flags)225 void __iomem * ioremap_prot(phys_addr_t addr, unsigned long size,
226 unsigned long flags)
227 {
228 void *caller = __builtin_return_address(0);
229
230 /* writeable implies dirty for kernel addresses */
231 if (flags & _PAGE_WRITE)
232 flags |= _PAGE_DIRTY;
233
234 /* we don't want to let _PAGE_EXEC leak out */
235 flags &= ~_PAGE_EXEC;
236 /*
237 * Force kernel mapping.
238 */
239 flags &= ~_PAGE_USER;
240 flags |= _PAGE_PRIVILEGED;
241
242 if (ppc_md.ioremap)
243 return ppc_md.ioremap(addr, size, flags, caller);
244 return __ioremap_caller(addr, size, flags, caller);
245 }
246
247
248 /*
249 * Unmap an IO region and remove it from imalloc'd list.
250 * Access to IO memory should be serialized by driver.
251 */
__iounmap(volatile void __iomem * token)252 void __iounmap(volatile void __iomem *token)
253 {
254 void *addr;
255
256 if (!slab_is_available())
257 return;
258
259 addr = (void *) ((unsigned long __force)
260 PCI_FIX_ADDR(token) & PAGE_MASK);
261 if ((unsigned long)addr < ioremap_bot) {
262 printk(KERN_WARNING "Attempt to iounmap early bolted mapping"
263 " at 0x%p\n", addr);
264 return;
265 }
266 vunmap(addr);
267 }
268
iounmap(volatile void __iomem * token)269 void iounmap(volatile void __iomem *token)
270 {
271 if (ppc_md.iounmap)
272 ppc_md.iounmap(token);
273 else
274 __iounmap(token);
275 }
276
277 EXPORT_SYMBOL(ioremap);
278 EXPORT_SYMBOL(ioremap_wc);
279 EXPORT_SYMBOL(ioremap_prot);
280 EXPORT_SYMBOL(__ioremap);
281 EXPORT_SYMBOL(__ioremap_at);
282 EXPORT_SYMBOL(iounmap);
283 EXPORT_SYMBOL(__iounmap);
284 EXPORT_SYMBOL(__iounmap_at);
285
286 #ifndef __PAGETABLE_PUD_FOLDED
287 /* 4 level page table */
pgd_page(pgd_t pgd)288 struct page *pgd_page(pgd_t pgd)
289 {
290 if (pgd_huge(pgd))
291 return pte_page(pgd_pte(pgd));
292 return virt_to_page(pgd_page_vaddr(pgd));
293 }
294 #endif
295
pud_page(pud_t pud)296 struct page *pud_page(pud_t pud)
297 {
298 if (pud_huge(pud))
299 return pte_page(pud_pte(pud));
300 return virt_to_page(pud_page_vaddr(pud));
301 }
302
303 /*
304 * For hugepage we have pfn in the pmd, we use PTE_RPN_SHIFT bits for flags
305 * For PTE page, we have a PTE_FRAG_SIZE (4K) aligned virtual address.
306 */
pmd_page(pmd_t pmd)307 struct page *pmd_page(pmd_t pmd)
308 {
309 if (pmd_trans_huge(pmd) || pmd_huge(pmd) || pmd_devmap(pmd))
310 return pte_page(pmd_pte(pmd));
311 return virt_to_page(pmd_page_vaddr(pmd));
312 }
313
314 #ifdef CONFIG_STRICT_KERNEL_RWX
mark_rodata_ro(void)315 void mark_rodata_ro(void)
316 {
317 if (!mmu_has_feature(MMU_FTR_KERNEL_RO)) {
318 pr_warn("Warning: Unable to mark rodata read only on this CPU.\n");
319 return;
320 }
321
322 if (radix_enabled())
323 radix__mark_rodata_ro();
324 else
325 hash__mark_rodata_ro();
326 }
327
mark_initmem_nx(void)328 void mark_initmem_nx(void)
329 {
330 if (radix_enabled())
331 radix__mark_initmem_nx();
332 else
333 hash__mark_initmem_nx();
334 }
335 #endif
336
