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
copy_user_highpage(struct page * to,struct page * from,unsigned long vaddr,struct vm_area_struct * vma)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
page_is_ram(unsigned long pfn)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
paging_init(void)64 void __init paging_init(void)
65 {
66 unsigned long max_zone_pfns[MAX_NR_ZONES];
67
68 #ifdef CONFIG_ZONE_DMA32
69 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
70 #endif
71 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
72
73 free_area_init(max_zone_pfns);
74 }
75 #endif /* !CONFIG_NUMA */
76
free_initmem(void)77 void __ref free_initmem(void)
78 {
79 free_initmem_default(POISON_FREE_INITMEM);
80 }
81
82 #ifdef CONFIG_MEMORY_HOTPLUG
arch_add_memory(int nid,u64 start,u64 size,struct mhp_params * params)83 int arch_add_memory(int nid, u64 start, u64 size, struct mhp_params *params)
84 {
85 unsigned long start_pfn = start >> PAGE_SHIFT;
86 unsigned long nr_pages = size >> PAGE_SHIFT;
87 int ret;
88
89 ret = __add_pages(nid, start_pfn, nr_pages, params);
90
91 if (ret)
92 pr_warn("%s: Problem encountered in __add_pages() as ret=%d\n",
93 __func__, ret);
94
95 return ret;
96 }
97
arch_remove_memory(u64 start,u64 size,struct vmem_altmap * altmap)98 void arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
99 {
100 unsigned long start_pfn = start >> PAGE_SHIFT;
101 unsigned long nr_pages = size >> PAGE_SHIFT;
102 struct page *page = pfn_to_page(start_pfn);
103
104 /* With altmap the first mapped page is offset from @start */
105 if (altmap)
106 page += vmem_altmap_offset(altmap);
107 __remove_pages(start_pfn, nr_pages, altmap);
108 }
109 #endif
110
111 #ifdef CONFIG_SPARSEMEM_VMEMMAP
vmemmap_set_pmd(pmd_t * pmd,void * p,int node,unsigned long addr,unsigned long next)112 void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
113 unsigned long addr, unsigned long next)
114 {
115 pmd_t entry;
116
117 entry = pfn_pmd(virt_to_pfn(p), PAGE_KERNEL);
118 pmd_val(entry) |= _PAGE_HUGE | _PAGE_HGLOBAL;
119 set_pmd_at(&init_mm, addr, pmd, entry);
120 }
121
vmemmap_check_pmd(pmd_t * pmd,int node,unsigned long addr,unsigned long next)122 int __meminit vmemmap_check_pmd(pmd_t *pmd, int node,
123 unsigned long addr, unsigned long next)
124 {
125 int huge = pmd_val(pmdp_get(pmd)) & _PAGE_HUGE;
126
127 if (huge)
128 vmemmap_verify((pte_t *)pmd, node, addr, next);
129
130 return huge;
131 }
132
vmemmap_populate(unsigned long start,unsigned long end,int node,struct vmem_altmap * altmap)133 int __meminit vmemmap_populate(unsigned long start, unsigned long end,
134 int node, struct vmem_altmap *altmap)
135 {
136 #if CONFIG_PGTABLE_LEVELS == 2
137 return vmemmap_populate_basepages(start, end, node, NULL);
138 #else
139 return vmemmap_populate_hugepages(start, end, node, NULL);
140 #endif
141 }
142
143 #ifdef CONFIG_MEMORY_HOTPLUG
vmemmap_free(unsigned long start,unsigned long end,struct vmem_altmap * altmap)144 void vmemmap_free(unsigned long start, unsigned long end, struct vmem_altmap *altmap)
145 {
146 }
147 #endif
148 #endif
149
populate_kernel_pte(unsigned long addr)150 pte_t * __init populate_kernel_pte(unsigned long addr)
151 {
152 pgd_t *pgd = pgd_offset_k(addr);
153 p4d_t *p4d = p4d_offset(pgd, addr);
154 pud_t *pud;
155 pmd_t *pmd;
156
157 if (p4d_none(p4dp_get(p4d))) {
158 pud = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
159 p4d_populate(&init_mm, p4d, pud);
160 #ifndef __PAGETABLE_PUD_FOLDED
161 pud_init(pud);
162 #endif
163 }
164
165 pud = pud_offset(p4d, addr);
166 if (pud_none(pudp_get(pud))) {
167 pmd = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
168 pud_populate(&init_mm, pud, pmd);
169 #ifndef __PAGETABLE_PMD_FOLDED
170 pmd_init(pmd);
171 #endif
172 }
173
174 pmd = pmd_offset(pud, addr);
175 if (!pmd_present(pmdp_get(pmd))) {
176 pte_t *pte;
177
178 pte = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
179 pmd_populate_kernel(&init_mm, pmd, pte);
180 kernel_pte_init(pte);
181 }
182
183 return pte_offset_kernel(pmd, addr);
184 }
185
__set_fixmap(enum fixed_addresses idx,phys_addr_t phys,pgprot_t flags)186 void __init __set_fixmap(enum fixed_addresses idx,
187 phys_addr_t phys, pgprot_t flags)
188 {
189 unsigned long addr = __fix_to_virt(idx);
190 pte_t *ptep;
191
192 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
193
194 ptep = populate_kernel_pte(addr);
195 if (!pte_none(ptep_get(ptep))) {
196 pte_ERROR(*ptep);
197 return;
198 }
199
200 if (pgprot_val(flags))
201 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags));
202 else {
203 pte_clear(&init_mm, addr, ptep);
204 flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
205 }
206 }
207
208 /*
209 * Align swapper_pg_dir in to 64K, allows its address to be loaded
210 * with a single LUI instruction in the TLB handlers. If we used
211 * __aligned(64K), its size would get rounded up to the alignment
212 * size, and waste space. So we place it in its own section and align
213 * it in the linker script.
214 */
215 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __section(".bss..swapper_pg_dir");
216
217 pgd_t invalid_pg_dir[_PTRS_PER_PGD] __page_aligned_bss;
218 #ifndef __PAGETABLE_PUD_FOLDED
219 pud_t invalid_pud_table[PTRS_PER_PUD] __page_aligned_bss;
220 EXPORT_SYMBOL(invalid_pud_table);
221 #endif
222 #ifndef __PAGETABLE_PMD_FOLDED
223 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss;
224 EXPORT_SYMBOL(invalid_pmd_table);
225 #endif
226 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
227 EXPORT_SYMBOL(invalid_pte_table);
228
229 #ifdef CONFIG_EXECMEM
230 static struct execmem_info execmem_info __ro_after_init;
231
execmem_arch_setup(void)232 struct execmem_info __init *execmem_arch_setup(void)
233 {
234 execmem_info = (struct execmem_info){
235 .ranges = {
236 [EXECMEM_DEFAULT] = {
237 .start = MODULES_VADDR,
238 .end = MODULES_END,
239 .pgprot = PAGE_KERNEL,
240 .alignment = 1,
241 },
242 },
243 };
244
245 return &execmem_info;
246 }
247 #endif /* CONFIG_EXECMEM */
248