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