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