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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * This file contains the routines setting up the linux page tables.
4 * -- paulus
5 *
6 * Derived from arch/ppc/mm/init.c:
7 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
8 *
9 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
10 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
11 * Copyright (C) 1996 Paul Mackerras
12 *
13 * Derived from "arch/i386/mm/init.c"
14 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
15 */
16
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/types.h>
20#include <linux/mm.h>
21#include <linux/vmalloc.h>
22#include <linux/init.h>
23#include <linux/highmem.h>
24#include <linux/memblock.h>
25#include <linux/slab.h>
26#include <linux/set_memory.h>
27
28#include <asm/pgalloc.h>
29#include <asm/fixmap.h>
30#include <asm/setup.h>
31#include <asm/sections.h>
32#include <asm/early_ioremap.h>
33
34#include <mm/mmu_decl.h>
35
36static u8 early_fixmap_pagetable[FIXMAP_PTE_SIZE] __page_aligned_data;
37
38notrace void __init early_ioremap_init(void)
39{
40 unsigned long addr = ALIGN_DOWN(FIXADDR_START, PGDIR_SIZE);
41 pte_t *ptep = (pte_t *)early_fixmap_pagetable;
42 pmd_t *pmdp = pmd_off_k(addr);
43
44 for (; (s32)(FIXADDR_TOP - addr) > 0;
45 addr += PGDIR_SIZE, ptep += PTRS_PER_PTE, pmdp++)
46 pmd_populate_kernel(&init_mm, pmdp, ptep);
47
48 early_ioremap_setup();
49}
50
51static void __init *early_alloc_pgtable(unsigned long size)
52{
53 void *ptr = memblock_alloc(size, size);
54
55 if (!ptr)
56 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
57 __func__, size, size);
58
59 return ptr;
60}
61
62pte_t __init *early_pte_alloc_kernel(pmd_t *pmdp, unsigned long va)
63{
64 if (pmd_none(*pmdp)) {
65 pte_t *ptep = early_alloc_pgtable(PTE_FRAG_SIZE);
66
67 pmd_populate_kernel(&init_mm, pmdp, ptep);
68 }
69 return pte_offset_kernel(pmdp, va);
70}
71
72
73int __ref map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot)
74{
75 pmd_t *pd;
76 pte_t *pg;
77 int err = -ENOMEM;
78
79 /* Use upper 10 bits of VA to index the first level map */
80 pd = pmd_off_k(va);
81 /* Use middle 10 bits of VA to index the second-level map */
82 if (likely(slab_is_available()))
83 pg = pte_alloc_kernel(pd, va);
84 else
85 pg = early_pte_alloc_kernel(pd, va);
86 if (pg) {
87 err = 0;
88 /* The PTE should never be already set nor present in the
89 * hash table
90 */
91 BUG_ON((pte_present(*pg) | pte_hashpte(*pg)) && pgprot_val(prot));
92 set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, prot));
93 }
94 smp_wmb();
95 return err;
96}
97
98/*
99 * Map in a chunk of physical memory starting at start.
100 */
101static void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
102{
103 unsigned long v, s;
104 phys_addr_t p;
105 bool ktext;
106
107 s = offset;
108 v = PAGE_OFFSET + s;
109 p = memstart_addr + s;
110 for (; s < top; s += PAGE_SIZE) {
111 ktext = core_kernel_text(v);
112 map_kernel_page(v, p, ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL);
113 v += PAGE_SIZE;
114 p += PAGE_SIZE;
115 }
116}
117
118void __init mapin_ram(void)
119{
120 phys_addr_t base, end;
121 u64 i;
122
123 for_each_mem_range(i, &base, &end) {
124 phys_addr_t top = min(end, total_lowmem);
125
126 if (base >= top)
127 continue;
128 base = mmu_mapin_ram(base, top);
129 __mapin_ram_chunk(base, top);
130 }
131}
132
133void mark_initmem_nx(void)
134{
135 unsigned long numpages = PFN_UP((unsigned long)_einittext) -
136 PFN_DOWN((unsigned long)_sinittext);
137
138 mmu_mark_initmem_nx();
139
140 if (!v_block_mapped((unsigned long)_sinittext)) {
141 set_memory_nx((unsigned long)_sinittext, numpages);
142 set_memory_rw((unsigned long)_sinittext, numpages);
143 }
144}
145
146#ifdef CONFIG_STRICT_KERNEL_RWX
147void mark_rodata_ro(void)
148{
149 unsigned long numpages;
150
151 if (IS_ENABLED(CONFIG_STRICT_MODULE_RWX) && mmu_has_feature(MMU_FTR_HPTE_TABLE))
152 pr_warn("This platform has HASH MMU, STRICT_MODULE_RWX won't work\n");
153
154 if (v_block_mapped((unsigned long)_stext + 1)) {
155 mmu_mark_rodata_ro();
156 ptdump_check_wx();
157 return;
158 }
159
160 /*
161 * mark text and rodata as read only. __end_rodata is set by
162 * powerpc's linker script and includes tables and data
163 * requiring relocation which are not put in RO_DATA.
164 */
165 numpages = PFN_UP((unsigned long)__end_rodata) -
166 PFN_DOWN((unsigned long)_stext);
167
168 set_memory_ro((unsigned long)_stext, numpages);
169
170 // mark_initmem_nx() should have already run by now
171 ptdump_check_wx();
172}
173#endif
174
175#if defined(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) && defined(CONFIG_DEBUG_PAGEALLOC)
176void __kernel_map_pages(struct page *page, int numpages, int enable)
177{
178 unsigned long addr = (unsigned long)page_address(page);
179
180 if (PageHighMem(page))
181 return;
182
183 if (enable)
184 set_memory_p(addr, numpages);
185 else
186 set_memory_np(addr, numpages);
187}
188#endif /* CONFIG_DEBUG_PAGEALLOC */
1/*
2 * This file contains the routines setting up the linux page tables.
3 * -- paulus
4 *
5 * Derived from arch/ppc/mm/init.c:
6 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
7 *
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
11 *
12 * Derived from "arch/i386/mm/init.c"
13 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
14 *
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.
19 *
20 */
21
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/types.h>
25#include <linux/mm.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>
31
32#include <asm/pgtable.h>
33#include <asm/pgalloc.h>
34#include <asm/fixmap.h>
35#include <asm/io.h>
36
37#include "mmu_decl.h"
38
39unsigned long ioremap_base;
40unsigned long ioremap_bot;
41EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */
42
43#if defined(CONFIG_6xx) || defined(CONFIG_POWER3)
44#define HAVE_BATS 1
45#endif
46
47#if defined(CONFIG_FSL_BOOKE)
48#define HAVE_TLBCAM 1
49#endif
50
51extern char etext[], _stext[];
52
53#ifdef HAVE_BATS
54extern phys_addr_t v_mapped_by_bats(unsigned long va);
55extern unsigned long p_mapped_by_bats(phys_addr_t pa);
56void setbat(int index, unsigned long virt, phys_addr_t phys,
57 unsigned int size, int flags);
58
59#else /* !HAVE_BATS */
60#define v_mapped_by_bats(x) (0UL)
61#define p_mapped_by_bats(x) (0UL)
62#endif /* HAVE_BATS */
63
64#ifdef HAVE_TLBCAM
65extern unsigned int tlbcam_index;
66extern phys_addr_t v_mapped_by_tlbcam(unsigned long va);
67extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa);
68#else /* !HAVE_TLBCAM */
69#define v_mapped_by_tlbcam(x) (0UL)
70#define p_mapped_by_tlbcam(x) (0UL)
71#endif /* HAVE_TLBCAM */
72
73#define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT)
74
75pgd_t *pgd_alloc(struct mm_struct *mm)
76{
77 pgd_t *ret;
78
79 /* pgdir take page or two with 4K pages and a page fraction otherwise */
80#ifndef CONFIG_PPC_4K_PAGES
81 ret = kzalloc(1 << PGDIR_ORDER, GFP_KERNEL);
82#else
83 ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
84 PGDIR_ORDER - PAGE_SHIFT);
85#endif
86 return ret;
87}
88
89void pgd_free(struct mm_struct *mm, pgd_t *pgd)
90{
91#ifndef CONFIG_PPC_4K_PAGES
92 kfree((void *)pgd);
93#else
94 free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT);
95#endif
96}
97
98__init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
99{
100 pte_t *pte;
101 extern int mem_init_done;
102 extern void *early_get_page(void);
103
104 if (mem_init_done) {
105 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
106 } else {
107 pte = (pte_t *)early_get_page();
108 if (pte)
109 clear_page(pte);
110 }
111 return pte;
112}
113
114pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
115{
116 struct page *ptepage;
117
118 gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO;
119
120 ptepage = alloc_pages(flags, 0);
121 if (!ptepage)
122 return NULL;
123 pgtable_page_ctor(ptepage);
124 return ptepage;
125}
126
127void __iomem *
128ioremap(phys_addr_t addr, unsigned long size)
129{
130 return __ioremap_caller(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED,
131 __builtin_return_address(0));
132}
133EXPORT_SYMBOL(ioremap);
134
135void __iomem *
136ioremap_wc(phys_addr_t addr, unsigned long size)
137{
138 return __ioremap_caller(addr, size, _PAGE_NO_CACHE,
139 __builtin_return_address(0));
140}
141EXPORT_SYMBOL(ioremap_wc);
142
143void __iomem *
144ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags)
145{
146 /* writeable implies dirty for kernel addresses */
147 if (flags & _PAGE_RW)
148 flags |= _PAGE_DIRTY | _PAGE_HWWRITE;
149
150 /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
151 flags &= ~(_PAGE_USER | _PAGE_EXEC);
152
153#ifdef _PAGE_BAP_SR
154 /* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
155 * which means that we just cleared supervisor access... oops ;-) This
156 * restores it
157 */
158 flags |= _PAGE_BAP_SR;
159#endif
160
161 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
162}
163EXPORT_SYMBOL(ioremap_prot);
164
165void __iomem *
166__ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
167{
168 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
169}
170
171void __iomem *
172__ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
173 void *caller)
174{
175 unsigned long v, i;
176 phys_addr_t p;
177 int err;
178
179 /* Make sure we have the base flags */
180 if ((flags & _PAGE_PRESENT) == 0)
181 flags |= PAGE_KERNEL;
182
183 /* Non-cacheable page cannot be coherent */
184 if (flags & _PAGE_NO_CACHE)
185 flags &= ~_PAGE_COHERENT;
186
187 /*
188 * Choose an address to map it to.
189 * Once the vmalloc system is running, we use it.
190 * Before then, we use space going down from ioremap_base
191 * (ioremap_bot records where we're up to).
192 */
193 p = addr & PAGE_MASK;
194 size = PAGE_ALIGN(addr + size) - p;
195
196 /*
197 * If the address lies within the first 16 MB, assume it's in ISA
198 * memory space
199 */
200 if (p < 16*1024*1024)
201 p += _ISA_MEM_BASE;
202
203#ifndef CONFIG_CRASH_DUMP
204 /*
205 * Don't allow anybody to remap normal RAM that we're using.
206 * mem_init() sets high_memory so only do the check after that.
207 */
208 if (mem_init_done && (p < virt_to_phys(high_memory)) &&
209 !(__allow_ioremap_reserved && memblock_is_region_reserved(p, size))) {
210 printk("__ioremap(): phys addr 0x%llx is RAM lr %p\n",
211 (unsigned long long)p, __builtin_return_address(0));
212 return NULL;
213 }
214#endif
215
216 if (size == 0)
217 return NULL;
218
219 /*
220 * Is it already mapped? Perhaps overlapped by a previous
221 * BAT mapping. If the whole area is mapped then we're done,
222 * otherwise remap it since we want to keep the virt addrs for
223 * each request contiguous.
224 *
225 * We make the assumption here that if the bottom and top
226 * of the range we want are mapped then it's mapped to the
227 * same virt address (and this is contiguous).
228 * -- Cort
229 */
230 if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ )
231 goto out;
232
233 if ((v = p_mapped_by_tlbcam(p)))
234 goto out;
235
236 if (mem_init_done) {
237 struct vm_struct *area;
238 area = get_vm_area_caller(size, VM_IOREMAP, caller);
239 if (area == 0)
240 return NULL;
241 area->phys_addr = p;
242 v = (unsigned long) area->addr;
243 } else {
244 v = (ioremap_bot -= size);
245 }
246
247 /*
248 * Should check if it is a candidate for a BAT mapping
249 */
250
251 err = 0;
252 for (i = 0; i < size && err == 0; i += PAGE_SIZE)
253 err = map_page(v+i, p+i, flags);
254 if (err) {
255 if (mem_init_done)
256 vunmap((void *)v);
257 return NULL;
258 }
259
260out:
261 return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
262}
263EXPORT_SYMBOL(__ioremap);
264
265void iounmap(volatile void __iomem *addr)
266{
267 /*
268 * If mapped by BATs then there is nothing to do.
269 * Calling vfree() generates a benign warning.
270 */
271 if (v_mapped_by_bats((unsigned long)addr)) return;
272
273 if (addr > high_memory && (unsigned long) addr < ioremap_bot)
274 vunmap((void *) (PAGE_MASK & (unsigned long)addr));
275}
276EXPORT_SYMBOL(iounmap);
277
278int map_page(unsigned long va, phys_addr_t pa, int flags)
279{
280 pmd_t *pd;
281 pte_t *pg;
282 int err = -ENOMEM;
283
284 /* Use upper 10 bits of VA to index the first level map */
285 pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va);
286 /* Use middle 10 bits of VA to index the second-level map */
287 pg = pte_alloc_kernel(pd, va);
288 if (pg != 0) {
289 err = 0;
290 /* The PTE should never be already set nor present in the
291 * hash table
292 */
293 BUG_ON((pte_val(*pg) & (_PAGE_PRESENT | _PAGE_HASHPTE)) &&
294 flags);
295 set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
296 __pgprot(flags)));
297 }
298 return err;
299}
300
301/*
302 * Map in a chunk of physical memory starting at start.
303 */
304void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
305{
306 unsigned long v, s, f;
307 phys_addr_t p;
308 int ktext;
309
310 s = offset;
311 v = PAGE_OFFSET + s;
312 p = memstart_addr + s;
313 for (; s < top; s += PAGE_SIZE) {
314 ktext = ((char *) v >= _stext && (char *) v < etext);
315 f = ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL;
316 map_page(v, p, f);
317#ifdef CONFIG_PPC_STD_MMU_32
318 if (ktext)
319 hash_preload(&init_mm, v, 0, 0x300);
320#endif
321 v += PAGE_SIZE;
322 p += PAGE_SIZE;
323 }
324}
325
326void __init mapin_ram(void)
327{
328 unsigned long s, top;
329
330#ifndef CONFIG_WII
331 top = total_lowmem;
332 s = mmu_mapin_ram(top);
333 __mapin_ram_chunk(s, top);
334#else
335 if (!wii_hole_size) {
336 s = mmu_mapin_ram(total_lowmem);
337 __mapin_ram_chunk(s, total_lowmem);
338 } else {
339 top = wii_hole_start;
340 s = mmu_mapin_ram(top);
341 __mapin_ram_chunk(s, top);
342
343 top = memblock_end_of_DRAM();
344 s = wii_mmu_mapin_mem2(top);
345 __mapin_ram_chunk(s, top);
346 }
347#endif
348}
349
350/* Scan the real Linux page tables and return a PTE pointer for
351 * a virtual address in a context.
352 * Returns true (1) if PTE was found, zero otherwise. The pointer to
353 * the PTE pointer is unmodified if PTE is not found.
354 */
355int
356get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp)
357{
358 pgd_t *pgd;
359 pud_t *pud;
360 pmd_t *pmd;
361 pte_t *pte;
362 int retval = 0;
363
364 pgd = pgd_offset(mm, addr & PAGE_MASK);
365 if (pgd) {
366 pud = pud_offset(pgd, addr & PAGE_MASK);
367 if (pud && pud_present(*pud)) {
368 pmd = pmd_offset(pud, addr & PAGE_MASK);
369 if (pmd_present(*pmd)) {
370 pte = pte_offset_map(pmd, addr & PAGE_MASK);
371 if (pte) {
372 retval = 1;
373 *ptep = pte;
374 if (pmdp)
375 *pmdp = pmd;
376 /* XXX caller needs to do pte_unmap, yuck */
377 }
378 }
379 }
380 }
381 return(retval);
382}
383
384#ifdef CONFIG_DEBUG_PAGEALLOC
385
386static int __change_page_attr(struct page *page, pgprot_t prot)
387{
388 pte_t *kpte;
389 pmd_t *kpmd;
390 unsigned long address;
391
392 BUG_ON(PageHighMem(page));
393 address = (unsigned long)page_address(page);
394
395 if (v_mapped_by_bats(address) || v_mapped_by_tlbcam(address))
396 return 0;
397 if (!get_pteptr(&init_mm, address, &kpte, &kpmd))
398 return -EINVAL;
399 __set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0);
400 wmb();
401 flush_tlb_page(NULL, address);
402 pte_unmap(kpte);
403
404 return 0;
405}
406
407/*
408 * Change the page attributes of an page in the linear mapping.
409 *
410 * THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY
411 */
412static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
413{
414 int i, err = 0;
415 unsigned long flags;
416
417 local_irq_save(flags);
418 for (i = 0; i < numpages; i++, page++) {
419 err = __change_page_attr(page, prot);
420 if (err)
421 break;
422 }
423 local_irq_restore(flags);
424 return err;
425}
426
427
428void kernel_map_pages(struct page *page, int numpages, int enable)
429{
430 if (PageHighMem(page))
431 return;
432
433 change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
434}
435#endif /* CONFIG_DEBUG_PAGEALLOC */
436
437static int fixmaps;
438
439void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
440{
441 unsigned long address = __fix_to_virt(idx);
442
443 if (idx >= __end_of_fixed_addresses) {
444 BUG();
445 return;
446 }
447
448 map_page(address, phys, pgprot_val(flags));
449 fixmaps++;
450}
451
452void __this_fixmap_does_not_exist(void)
453{
454 WARN_ON(1);
455}