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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#include <asm/setup.h>
37
38#include "mmu_decl.h"
39
40unsigned long ioremap_base;
41unsigned long ioremap_bot;
42EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */
43
44#if defined(CONFIG_6xx) || defined(CONFIG_POWER3)
45#define HAVE_BATS 1
46#endif
47
48#if defined(CONFIG_FSL_BOOKE)
49#define HAVE_TLBCAM 1
50#endif
51
52extern char etext[], _stext[];
53
54#ifdef HAVE_BATS
55extern phys_addr_t v_mapped_by_bats(unsigned long va);
56extern unsigned long p_mapped_by_bats(phys_addr_t pa);
57void setbat(int index, unsigned long virt, phys_addr_t phys,
58 unsigned int size, int flags);
59
60#else /* !HAVE_BATS */
61#define v_mapped_by_bats(x) (0UL)
62#define p_mapped_by_bats(x) (0UL)
63#endif /* HAVE_BATS */
64
65#ifdef HAVE_TLBCAM
66extern unsigned int tlbcam_index;
67extern phys_addr_t v_mapped_by_tlbcam(unsigned long va);
68extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa);
69#else /* !HAVE_TLBCAM */
70#define v_mapped_by_tlbcam(x) (0UL)
71#define p_mapped_by_tlbcam(x) (0UL)
72#endif /* HAVE_TLBCAM */
73
74#define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT)
75
76pgd_t *pgd_alloc(struct mm_struct *mm)
77{
78 pgd_t *ret;
79
80 /* pgdir take page or two with 4K pages and a page fraction otherwise */
81#ifndef CONFIG_PPC_4K_PAGES
82 ret = kzalloc(1 << PGDIR_ORDER, GFP_KERNEL);
83#else
84 ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
85 PGDIR_ORDER - PAGE_SHIFT);
86#endif
87 return ret;
88}
89
90void pgd_free(struct mm_struct *mm, pgd_t *pgd)
91{
92#ifndef CONFIG_PPC_4K_PAGES
93 kfree((void *)pgd);
94#else
95 free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT);
96#endif
97}
98
99__init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
100{
101 pte_t *pte;
102 extern int mem_init_done;
103 extern void *early_get_page(void);
104
105 if (mem_init_done) {
106 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
107 } else {
108 pte = (pte_t *)early_get_page();
109 if (pte)
110 clear_page(pte);
111 }
112 return pte;
113}
114
115pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
116{
117 struct page *ptepage;
118
119 gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO;
120
121 ptepage = alloc_pages(flags, 0);
122 if (!ptepage)
123 return NULL;
124 if (!pgtable_page_ctor(ptepage)) {
125 __free_page(ptepage);
126 return NULL;
127 }
128 return ptepage;
129}
130
131void __iomem *
132ioremap(phys_addr_t addr, unsigned long size)
133{
134 return __ioremap_caller(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED,
135 __builtin_return_address(0));
136}
137EXPORT_SYMBOL(ioremap);
138
139void __iomem *
140ioremap_wc(phys_addr_t addr, unsigned long size)
141{
142 return __ioremap_caller(addr, size, _PAGE_NO_CACHE,
143 __builtin_return_address(0));
144}
145EXPORT_SYMBOL(ioremap_wc);
146
147void __iomem *
148ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags)
149{
150 /* writeable implies dirty for kernel addresses */
151 if (flags & _PAGE_RW)
152 flags |= _PAGE_DIRTY | _PAGE_HWWRITE;
153
154 /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
155 flags &= ~(_PAGE_USER | _PAGE_EXEC);
156
157#ifdef _PAGE_BAP_SR
158 /* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
159 * which means that we just cleared supervisor access... oops ;-) This
160 * restores it
161 */
162 flags |= _PAGE_BAP_SR;
163#endif
164
165 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
166}
167EXPORT_SYMBOL(ioremap_prot);
168
169void __iomem *
170__ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
171{
172 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
173}
174
175void __iomem *
176__ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
177 void *caller)
178{
179 unsigned long v, i;
180 phys_addr_t p;
181 int err;
182
183 /* Make sure we have the base flags */
184 if ((flags & _PAGE_PRESENT) == 0)
185 flags |= PAGE_KERNEL;
186
187 /* Non-cacheable page cannot be coherent */
188 if (flags & _PAGE_NO_CACHE)
189 flags &= ~_PAGE_COHERENT;
190
191 /*
192 * Choose an address to map it to.
193 * Once the vmalloc system is running, we use it.
194 * Before then, we use space going down from ioremap_base
195 * (ioremap_bot records where we're up to).
196 */
197 p = addr & PAGE_MASK;
198 size = PAGE_ALIGN(addr + size) - p;
199
200 /*
201 * If the address lies within the first 16 MB, assume it's in ISA
202 * memory space
203 */
204 if (p < 16*1024*1024)
205 p += _ISA_MEM_BASE;
206
207#ifndef CONFIG_CRASH_DUMP
208 /*
209 * Don't allow anybody to remap normal RAM that we're using.
210 * mem_init() sets high_memory so only do the check after that.
211 */
212 if (mem_init_done && (p < virt_to_phys(high_memory)) &&
213 !(__allow_ioremap_reserved && memblock_is_region_reserved(p, size))) {
214 printk("__ioremap(): phys addr 0x%llx is RAM lr %pf\n",
215 (unsigned long long)p, __builtin_return_address(0));
216 return NULL;
217 }
218#endif
219
220 if (size == 0)
221 return NULL;
222
223 /*
224 * Is it already mapped? Perhaps overlapped by a previous
225 * BAT mapping. If the whole area is mapped then we're done,
226 * otherwise remap it since we want to keep the virt addrs for
227 * each request contiguous.
228 *
229 * We make the assumption here that if the bottom and top
230 * of the range we want are mapped then it's mapped to the
231 * same virt address (and this is contiguous).
232 * -- Cort
233 */
234 if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ )
235 goto out;
236
237 if ((v = p_mapped_by_tlbcam(p)))
238 goto out;
239
240 if (mem_init_done) {
241 struct vm_struct *area;
242 area = get_vm_area_caller(size, VM_IOREMAP, caller);
243 if (area == 0)
244 return NULL;
245 area->phys_addr = p;
246 v = (unsigned long) area->addr;
247 } else {
248 v = (ioremap_bot -= size);
249 }
250
251 /*
252 * Should check if it is a candidate for a BAT mapping
253 */
254
255 err = 0;
256 for (i = 0; i < size && err == 0; i += PAGE_SIZE)
257 err = map_page(v+i, p+i, flags);
258 if (err) {
259 if (mem_init_done)
260 vunmap((void *)v);
261 return NULL;
262 }
263
264out:
265 return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
266}
267EXPORT_SYMBOL(__ioremap);
268
269void iounmap(volatile void __iomem *addr)
270{
271 /*
272 * If mapped by BATs then there is nothing to do.
273 * Calling vfree() generates a benign warning.
274 */
275 if (v_mapped_by_bats((unsigned long)addr)) return;
276
277 if (addr > high_memory && (unsigned long) addr < ioremap_bot)
278 vunmap((void *) (PAGE_MASK & (unsigned long)addr));
279}
280EXPORT_SYMBOL(iounmap);
281
282int map_page(unsigned long va, phys_addr_t pa, int flags)
283{
284 pmd_t *pd;
285 pte_t *pg;
286 int err = -ENOMEM;
287
288 /* Use upper 10 bits of VA to index the first level map */
289 pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va);
290 /* Use middle 10 bits of VA to index the second-level map */
291 pg = pte_alloc_kernel(pd, va);
292 if (pg != 0) {
293 err = 0;
294 /* The PTE should never be already set nor present in the
295 * hash table
296 */
297 BUG_ON((pte_val(*pg) & (_PAGE_PRESENT | _PAGE_HASHPTE)) &&
298 flags);
299 set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
300 __pgprot(flags)));
301 }
302 smp_wmb();
303 return err;
304}
305
306/*
307 * Map in a chunk of physical memory starting at start.
308 */
309void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
310{
311 unsigned long v, s, f;
312 phys_addr_t p;
313 int ktext;
314
315 s = offset;
316 v = PAGE_OFFSET + s;
317 p = memstart_addr + s;
318 for (; s < top; s += PAGE_SIZE) {
319 ktext = ((char *) v >= _stext && (char *) v < etext);
320 f = ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL;
321 map_page(v, p, f);
322#ifdef CONFIG_PPC_STD_MMU_32
323 if (ktext)
324 hash_preload(&init_mm, v, 0, 0x300);
325#endif
326 v += PAGE_SIZE;
327 p += PAGE_SIZE;
328 }
329}
330
331void __init mapin_ram(void)
332{
333 unsigned long s, top;
334
335#ifndef CONFIG_WII
336 top = total_lowmem;
337 s = mmu_mapin_ram(top);
338 __mapin_ram_chunk(s, top);
339#else
340 if (!wii_hole_size) {
341 s = mmu_mapin_ram(total_lowmem);
342 __mapin_ram_chunk(s, total_lowmem);
343 } else {
344 top = wii_hole_start;
345 s = mmu_mapin_ram(top);
346 __mapin_ram_chunk(s, top);
347
348 top = memblock_end_of_DRAM();
349 s = wii_mmu_mapin_mem2(top);
350 __mapin_ram_chunk(s, top);
351 }
352#endif
353}
354
355/* Scan the real Linux page tables and return a PTE pointer for
356 * a virtual address in a context.
357 * Returns true (1) if PTE was found, zero otherwise. The pointer to
358 * the PTE pointer is unmodified if PTE is not found.
359 */
360int
361get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp)
362{
363 pgd_t *pgd;
364 pud_t *pud;
365 pmd_t *pmd;
366 pte_t *pte;
367 int retval = 0;
368
369 pgd = pgd_offset(mm, addr & PAGE_MASK);
370 if (pgd) {
371 pud = pud_offset(pgd, addr & PAGE_MASK);
372 if (pud && pud_present(*pud)) {
373 pmd = pmd_offset(pud, addr & PAGE_MASK);
374 if (pmd_present(*pmd)) {
375 pte = pte_offset_map(pmd, addr & PAGE_MASK);
376 if (pte) {
377 retval = 1;
378 *ptep = pte;
379 if (pmdp)
380 *pmdp = pmd;
381 /* XXX caller needs to do pte_unmap, yuck */
382 }
383 }
384 }
385 }
386 return(retval);
387}
388
389#ifdef CONFIG_DEBUG_PAGEALLOC
390
391static int __change_page_attr(struct page *page, pgprot_t prot)
392{
393 pte_t *kpte;
394 pmd_t *kpmd;
395 unsigned long address;
396
397 BUG_ON(PageHighMem(page));
398 address = (unsigned long)page_address(page);
399
400 if (v_mapped_by_bats(address) || v_mapped_by_tlbcam(address))
401 return 0;
402 if (!get_pteptr(&init_mm, address, &kpte, &kpmd))
403 return -EINVAL;
404 __set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0);
405 wmb();
406 flush_tlb_page(NULL, address);
407 pte_unmap(kpte);
408
409 return 0;
410}
411
412/*
413 * Change the page attributes of an page in the linear mapping.
414 *
415 * THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY
416 */
417static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
418{
419 int i, err = 0;
420 unsigned long flags;
421
422 local_irq_save(flags);
423 for (i = 0; i < numpages; i++, page++) {
424 err = __change_page_attr(page, prot);
425 if (err)
426 break;
427 }
428 local_irq_restore(flags);
429 return err;
430}
431
432
433void kernel_map_pages(struct page *page, int numpages, int enable)
434{
435 if (PageHighMem(page))
436 return;
437
438 change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
439}
440#endif /* CONFIG_DEBUG_PAGEALLOC */
441
442static int fixmaps;
443
444void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
445{
446 unsigned long address = __fix_to_virt(idx);
447
448 if (idx >= __end_of_fixed_addresses) {
449 BUG();
450 return;
451 }
452
453 map_page(address, phys, pgprot_val(flags));
454 fixmaps++;
455}
456
457void __this_fixmap_does_not_exist(void)
458{
459 WARN_ON(1);
460}