1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. 3 4 #include <linux/module.h> 5 #include <linux/highmem.h> 6 #include <linux/smp.h> 7 #include <linux/memblock.h> 8 #include <asm/fixmap.h> 9 #include <asm/tlbflush.h> 10 #include <asm/cacheflush.h> 11 12 static pte_t *kmap_pte; 13 14 unsigned long highstart_pfn, highend_pfn; 15 16 void kmap_flush_tlb(unsigned long addr) 17 { 18 flush_tlb_one(addr); 19 } 20 EXPORT_SYMBOL(kmap_flush_tlb); 21 22 void *kmap_atomic_high_prot(struct page *page, pgprot_t prot) 23 { 24 unsigned long vaddr; 25 int idx, type; 26 27 type = kmap_atomic_idx_push(); 28 idx = type + KM_TYPE_NR*smp_processor_id(); 29 vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); 30 #ifdef CONFIG_DEBUG_HIGHMEM 31 BUG_ON(!pte_none(*(kmap_pte - idx))); 32 #endif 33 set_pte(kmap_pte-idx, mk_pte(page, prot)); 34 flush_tlb_one((unsigned long)vaddr); 35 36 return (void *)vaddr; 37 } 38 EXPORT_SYMBOL(kmap_atomic_high_prot); 39 40 void kunmap_atomic_high(void *kvaddr) 41 { 42 unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; 43 int idx; 44 45 if (vaddr < FIXADDR_START) 46 return; 47 48 #ifdef CONFIG_DEBUG_HIGHMEM 49 idx = KM_TYPE_NR*smp_processor_id() + kmap_atomic_idx(); 50 51 BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx)); 52 53 pte_clear(&init_mm, vaddr, kmap_pte - idx); 54 flush_tlb_one(vaddr); 55 #else 56 (void) idx; /* to kill a warning */ 57 #endif 58 kmap_atomic_idx_pop(); 59 } 60 EXPORT_SYMBOL(kunmap_atomic_high); 61 62 /* 63 * This is the same as kmap_atomic() but can map memory that doesn't 64 * have a struct page associated with it. 65 */ 66 void *kmap_atomic_pfn(unsigned long pfn) 67 { 68 unsigned long vaddr; 69 int idx, type; 70 71 pagefault_disable(); 72 73 type = kmap_atomic_idx_push(); 74 idx = type + KM_TYPE_NR*smp_processor_id(); 75 vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); 76 set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL)); 77 flush_tlb_one(vaddr); 78 79 return (void *) vaddr; 80 } 81 82 static void __init kmap_pages_init(void) 83 { 84 unsigned long vaddr; 85 pgd_t *pgd; 86 pmd_t *pmd; 87 pud_t *pud; 88 pte_t *pte; 89 90 vaddr = PKMAP_BASE; 91 fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, swapper_pg_dir); 92 93 pgd = swapper_pg_dir + pgd_index(vaddr); 94 pud = (pud_t *)pgd; 95 pmd = pmd_offset(pud, vaddr); 96 pte = pte_offset_kernel(pmd, vaddr); 97 pkmap_page_table = pte; 98 } 99 100 void __init kmap_init(void) 101 { 102 unsigned long vaddr; 103 104 kmap_pages_init(); 105 106 vaddr = __fix_to_virt(FIX_KMAP_BEGIN); 107 108 kmap_pte = pte_offset_kernel((pmd_t *)pgd_offset_k(vaddr), vaddr); 109 } 110