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