arch/loongarch/mm/init.c

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