1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4 */
5 #include <linux/init.h>
6 #include <linux/export.h>
7 #include <linux/signal.h>
8 #include <linux/sched.h>
9 #include <linux/smp.h>
10 #include <linux/kernel.h>
11 #include <linux/errno.h>
12 #include <linux/string.h>
13 #include <linux/types.h>
14 #include <linux/pagemap.h>
15 #include <linux/memblock.h>
16 #include <linux/memremap.h>
17 #include <linux/mm.h>
18 #include <linux/mman.h>
19 #include <linux/highmem.h>
20 #include <linux/swap.h>
21 #include <linux/proc_fs.h>
22 #include <linux/pfn.h>
23 #include <linux/hardirq.h>
24 #include <linux/gfp.h>
25 #include <linux/hugetlb.h>
26 #include <linux/mmzone.h>
27 #include <linux/execmem.h>
28
29 #include <asm/asm-offsets.h>
30 #include <asm/bootinfo.h>
31 #include <asm/cpu.h>
32 #include <asm/dma.h>
33 #include <asm/mmu_context.h>
34 #include <asm/sections.h>
35 #include <asm/pgtable.h>
36 #include <asm/pgalloc.h>
37 #include <asm/tlb.h>
38
39 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
40 EXPORT_SYMBOL(empty_zero_page);
41
42 void copy_user_highpage(struct page *to, struct page *from,
43 unsigned long vaddr, struct vm_area_struct *vma)
44 {
45 void *vfrom, *vto;
46
47 vfrom = kmap_local_page(from);
48 vto = kmap_local_page(to);
49 copy_page(vto, vfrom);
50 kunmap_local(vfrom);
51 kunmap_local(vto);
52 /* Make sure this page is cleared on other CPU's too before using it */
53 smp_wmb();
54 }
55
56 int __ref page_is_ram(unsigned long pfn)
57 {
58 unsigned long addr = PFN_PHYS(pfn);
59
60 return memblock_is_memory(addr) && !memblock_is_reserved(addr);
61 }
62
63 #ifndef CONFIG_NUMA
64 void __init paging_init(void)
65 {
66 unsigned long max_zone_pfns[MAX_NR_ZONES];
67
68 #ifdef CONFIG_ZONE_DMA
69 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
70 #endif
71 #ifdef CONFIG_ZONE_DMA32
72 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
73 #endif
74 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
75
76 free_area_init(max_zone_pfns);
77 }
78
79 void __init mem_init(void)
80 {
81 max_mapnr = max_low_pfn;
82 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
83
84 memblock_free_all();
85 }
86 #endif /* !CONFIG_NUMA */
87
88 void __ref free_initmem(void)
89 {
90 free_initmem_default(POISON_FREE_INITMEM);
91 }
92
93 #ifdef CONFIG_MEMORY_HOTPLUG
94 int arch_add_memory(int nid, u64 start, u64 size, struct mhp_params *params)
95 {
96 unsigned long start_pfn = start >> PAGE_SHIFT;
97 unsigned long nr_pages = size >> PAGE_SHIFT;
98 int ret;
99
100 ret = __add_pages(nid, start_pfn, nr_pages, params);
101
102 if (ret)
103 pr_warn("%s: Problem encountered in __add_pages() as ret=%d\n",
104 __func__, ret);
105
106 return ret;
107 }
108
109 void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
110 {
111 unsigned long start_pfn = start >> PAGE_SHIFT;
112 unsigned long nr_pages = size >> PAGE_SHIFT;
113 struct page *page = pfn_to_page(start_pfn);
114
115 /* With altmap the first mapped page is offset from @start */
116 if (altmap)
117 page += vmem_altmap_offset(altmap);
118 __remove_pages(start_pfn, nr_pages, altmap);
119 }
120
121 #ifdef CONFIG_NUMA
122 int memory_add_physaddr_to_nid(u64 start)
123 {
124 return pa_to_nid(start);
125 }
126 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
127 #endif
128 #endif
129
130 #ifdef CONFIG_SPARSEMEM_VMEMMAP
131 void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
132 unsigned long addr, unsigned long next)
133 {
134 pmd_t entry;
135
136 entry = pfn_pmd(virt_to_pfn(p), PAGE_KERNEL);
137 pmd_val(entry) |= _PAGE_HUGE | _PAGE_HGLOBAL;
138 set_pmd_at(&init_mm, addr, pmd, entry);
139 }
140
141 int __meminit vmemmap_check_pmd(pmd_t *pmd, int node,
142 unsigned long addr, unsigned long next)
143 {
144 int huge = pmd_val(pmdp_get(pmd)) & _PAGE_HUGE;
145
146 if (huge)
147 vmemmap_verify((pte_t *)pmd, node, addr, next);
148
149 return huge;
150 }
151
152 int __meminit vmemmap_populate(unsigned long start, unsigned long end,
153 int node, struct vmem_altmap *altmap)
154 {
155 #if CONFIG_PGTABLE_LEVELS == 2
156 return vmemmap_populate_basepages(start, end, node, NULL);
157 #else
158 return vmemmap_populate_hugepages(start, end, node, NULL);
159 #endif
160 }
161
162 #ifdef CONFIG_MEMORY_HOTPLUG
163 void vmemmap_free(unsigned long start, unsigned long end, struct vmem_altmap *altmap)
164 {
165 }
166 #endif
167 #endif
168
169 pte_t * __init populate_kernel_pte(unsigned long addr)
170 {
171 pgd_t *pgd = pgd_offset_k(addr);
172 p4d_t *p4d = p4d_offset(pgd, addr);
173 pud_t *pud;
174 pmd_t *pmd;
175
176 if (p4d_none(p4dp_get(p4d))) {
177 pud = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
178 if (!pud)
179 panic("%s: Failed to allocate memory\n", __func__);
180 p4d_populate(&init_mm, p4d, pud);
181 #ifndef __PAGETABLE_PUD_FOLDED
182 pud_init(pud);
183 #endif
184 }
185
186 pud = pud_offset(p4d, addr);
187 if (pud_none(pudp_get(pud))) {
188 pmd = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
189 if (!pmd)
190 panic("%s: Failed to allocate memory\n", __func__);
191 pud_populate(&init_mm, pud, pmd);
192 #ifndef __PAGETABLE_PMD_FOLDED
193 pmd_init(pmd);
194 #endif
195 }
196
197 pmd = pmd_offset(pud, addr);
198 if (!pmd_present(pmdp_get(pmd))) {
199 pte_t *pte;
200
201 pte = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
202 if (!pte)
203 panic("%s: Failed to allocate memory\n", __func__);
204 pmd_populate_kernel(&init_mm, pmd, pte);
205 }
206
207 return pte_offset_kernel(pmd, addr);
208 }
209
210 void __init __set_fixmap(enum fixed_addresses idx,
211 phys_addr_t phys, pgprot_t flags)
212 {
213 unsigned long addr = __fix_to_virt(idx);
214 pte_t *ptep;
215
216 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
217
218 ptep = populate_kernel_pte(addr);
219 if (!pte_none(ptep_get(ptep))) {
220 pte_ERROR(*ptep);
221 return;
222 }
223
224 if (pgprot_val(flags))
225 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags));
226 else {
227 pte_clear(&init_mm, addr, ptep);
228 flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
229 }
230 }
231
232 /*
233 * Align swapper_pg_dir in to 64K, allows its address to be loaded
234 * with a single LUI instruction in the TLB handlers. If we used
235 * __aligned(64K), its size would get rounded up to the alignment
236 * size, and waste space. So we place it in its own section and align
237 * it in the linker script.
238 */
239 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __section(".bss..swapper_pg_dir");
240
241 pgd_t invalid_pg_dir[_PTRS_PER_PGD] __page_aligned_bss;
242 #ifndef __PAGETABLE_PUD_FOLDED
243 pud_t invalid_pud_table[PTRS_PER_PUD] __page_aligned_bss;
244 EXPORT_SYMBOL(invalid_pud_table);
245 #endif
246 #ifndef __PAGETABLE_PMD_FOLDED
247 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss;
248 EXPORT_SYMBOL(invalid_pmd_table);
249 #endif
250 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
251 EXPORT_SYMBOL(invalid_pte_table);
252
253 #ifdef CONFIG_EXECMEM
254 static struct execmem_info execmem_info __ro_after_init;
255
256 struct execmem_info __init *execmem_arch_setup(void)
257 {
258 execmem_info = (struct execmem_info){
259 .ranges = {
260 [EXECMEM_DEFAULT] = {
261 .start = MODULES_VADDR,
262 .end = MODULES_END,
263 .pgprot = PAGE_KERNEL,
264 .alignment = 1,
265 },
266 },
267 };
268
269 return &execmem_info;
270 }
271 #endif /* CONFIG_EXECMEM */
272
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