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_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 77 void __ref free_initmem(void) 78 { 79 free_initmem_default(POISON_FREE_INITMEM); 80 } 81 82 #ifdef CONFIG_MEMORY_HOTPLUG 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 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 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 } 121 122 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 } 132 133 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 144 void vmemmap_free(unsigned long start, unsigned long end, struct vmem_altmap *altmap) 145 { 146 } 147 #endif 148 #endif 149 150 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 } 185 186 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; 231 232 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