This source file includes following definitions.
- early_alloc_pgtable
- early_pte_alloc_kernel
- map_kernel_page
- __mapin_ram_chunk
- mapin_ram
- get_pteptr
- __change_page_attr_noflush
- change_page_attr
- mark_initmem_nx
- mark_rodata_ro
- __kernel_map_pages
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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
27 #include <asm/pgtable.h>
28 #include <asm/pgalloc.h>
29 #include <asm/fixmap.h>
30 #include <asm/setup.h>
31 #include <asm/sections.h>
32
33 #include <mm/mmu_decl.h>
34
35 extern char etext[], _stext[], _sinittext[], _einittext[];
36
37 static void __init *early_alloc_pgtable(unsigned long size)
38 {
39 void *ptr = memblock_alloc(size, size);
40
41 if (!ptr)
42 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
43 __func__, size, size);
44
45 return ptr;
46 }
47
48 static pte_t __init *early_pte_alloc_kernel(pmd_t *pmdp, unsigned long va)
49 {
50 if (pmd_none(*pmdp)) {
51 pte_t *ptep = early_alloc_pgtable(PTE_FRAG_SIZE);
52
53 pmd_populate_kernel(&init_mm, pmdp, ptep);
54 }
55 return pte_offset_kernel(pmdp, va);
56 }
57
58
59 int __ref map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot)
60 {
61 pmd_t *pd;
62 pte_t *pg;
63 int err = -ENOMEM;
64
65
66 pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va);
67
68 if (likely(slab_is_available()))
69 pg = pte_alloc_kernel(pd, va);
70 else
71 pg = early_pte_alloc_kernel(pd, va);
72 if (pg != 0) {
73 err = 0;
74
75
76
77 BUG_ON((pte_present(*pg) | pte_hashpte(*pg)) && pgprot_val(prot));
78 set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, prot));
79 }
80 smp_wmb();
81 return err;
82 }
83
84
85
86
87 static void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
88 {
89 unsigned long v, s;
90 phys_addr_t p;
91 int ktext;
92
93 s = offset;
94 v = PAGE_OFFSET + s;
95 p = memstart_addr + s;
96 for (; s < top; s += PAGE_SIZE) {
97 ktext = ((char *)v >= _stext && (char *)v < etext) ||
98 ((char *)v >= _sinittext && (char *)v < _einittext);
99 map_kernel_page(v, p, ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL);
100 #ifdef CONFIG_PPC_BOOK3S_32
101 if (ktext)
102 hash_preload(&init_mm, v);
103 #endif
104 v += PAGE_SIZE;
105 p += PAGE_SIZE;
106 }
107 }
108
109 void __init mapin_ram(void)
110 {
111 struct memblock_region *reg;
112
113 for_each_memblock(memory, reg) {
114 phys_addr_t base = reg->base;
115 phys_addr_t top = min(base + reg->size, total_lowmem);
116
117 if (base >= top)
118 continue;
119 base = mmu_mapin_ram(base, top);
120 if (IS_ENABLED(CONFIG_BDI_SWITCH))
121 __mapin_ram_chunk(reg->base, top);
122 else
123 __mapin_ram_chunk(base, top);
124 }
125 }
126
127
128
129
130
131
132 static int
133 get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp)
134 {
135 pgd_t *pgd;
136 pud_t *pud;
137 pmd_t *pmd;
138 pte_t *pte;
139 int retval = 0;
140
141 pgd = pgd_offset(mm, addr & PAGE_MASK);
142 if (pgd) {
143 pud = pud_offset(pgd, addr & PAGE_MASK);
144 if (pud && pud_present(*pud)) {
145 pmd = pmd_offset(pud, addr & PAGE_MASK);
146 if (pmd_present(*pmd)) {
147 pte = pte_offset_map(pmd, addr & PAGE_MASK);
148 if (pte) {
149 retval = 1;
150 *ptep = pte;
151 if (pmdp)
152 *pmdp = pmd;
153
154 }
155 }
156 }
157 }
158 return(retval);
159 }
160
161 static int __change_page_attr_noflush(struct page *page, pgprot_t prot)
162 {
163 pte_t *kpte;
164 pmd_t *kpmd;
165 unsigned long address;
166
167 BUG_ON(PageHighMem(page));
168 address = (unsigned long)page_address(page);
169
170 if (v_block_mapped(address))
171 return 0;
172 if (!get_pteptr(&init_mm, address, &kpte, &kpmd))
173 return -EINVAL;
174 __set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0);
175 pte_unmap(kpte);
176
177 return 0;
178 }
179
180
181
182
183
184
185 static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
186 {
187 int i, err = 0;
188 unsigned long flags;
189 struct page *start = page;
190
191 local_irq_save(flags);
192 for (i = 0; i < numpages; i++, page++) {
193 err = __change_page_attr_noflush(page, prot);
194 if (err)
195 break;
196 }
197 wmb();
198 local_irq_restore(flags);
199 flush_tlb_kernel_range((unsigned long)page_address(start),
200 (unsigned long)page_address(page));
201 return err;
202 }
203
204 void mark_initmem_nx(void)
205 {
206 struct page *page = virt_to_page(_sinittext);
207 unsigned long numpages = PFN_UP((unsigned long)_einittext) -
208 PFN_DOWN((unsigned long)_sinittext);
209
210 if (v_block_mapped((unsigned long)_stext + 1))
211 mmu_mark_initmem_nx();
212 else
213 change_page_attr(page, numpages, PAGE_KERNEL);
214 }
215
216 #ifdef CONFIG_STRICT_KERNEL_RWX
217 void mark_rodata_ro(void)
218 {
219 struct page *page;
220 unsigned long numpages;
221
222 if (v_block_mapped((unsigned long)_sinittext)) {
223 mmu_mark_rodata_ro();
224 ptdump_check_wx();
225 return;
226 }
227
228 page = virt_to_page(_stext);
229 numpages = PFN_UP((unsigned long)_etext) -
230 PFN_DOWN((unsigned long)_stext);
231
232 change_page_attr(page, numpages, PAGE_KERNEL_ROX);
233
234
235
236
237 page = virt_to_page(__start_rodata);
238 numpages = PFN_UP((unsigned long)__init_begin) -
239 PFN_DOWN((unsigned long)__start_rodata);
240
241 change_page_attr(page, numpages, PAGE_KERNEL_RO);
242
243
244 ptdump_check_wx();
245 }
246 #endif
247
248 #ifdef CONFIG_DEBUG_PAGEALLOC
249 void __kernel_map_pages(struct page *page, int numpages, int enable)
250 {
251 if (PageHighMem(page))
252 return;
253
254 change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
255 }
256 #endif