1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/memblock.h> 3 #include <linux/mmdebug.h> 4 #include <linux/export.h> 5 #include <linux/mm.h> 6 7 #include <asm/page.h> 8 #include <linux/vmalloc.h> 9 10 #include "physaddr.h" 11 12 #ifdef CONFIG_X86_64 13 14 #ifdef CONFIG_DEBUG_VIRTUAL 15 unsigned long __phys_addr(unsigned long x) 16 { 17 unsigned long y = x - __START_KERNEL_map; 18 19 /* use the carry flag to determine if x was < __START_KERNEL_map */ 20 if (unlikely(x > y)) { 21 x = y + phys_base; 22 23 VIRTUAL_BUG_ON(y >= KERNEL_IMAGE_SIZE); 24 } else { 25 x = y + (__START_KERNEL_map - PAGE_OFFSET); 26 27 /* carry flag will be set if starting x was >= PAGE_OFFSET */ 28 VIRTUAL_BUG_ON((x > y) || !phys_addr_valid(x)); 29 } 30 31 return x; 32 } 33 EXPORT_SYMBOL(__phys_addr); 34 35 unsigned long __phys_addr_symbol(unsigned long x) 36 { 37 unsigned long y = x - __START_KERNEL_map; 38 39 /* only check upper bounds since lower bounds will trigger carry */ 40 VIRTUAL_BUG_ON(y >= KERNEL_IMAGE_SIZE); 41 42 return y + phys_base; 43 } 44 EXPORT_SYMBOL(__phys_addr_symbol); 45 #endif 46 47 bool __virt_addr_valid(unsigned long x) 48 { 49 unsigned long y = x - __START_KERNEL_map; 50 51 /* use the carry flag to determine if x was < __START_KERNEL_map */ 52 if (unlikely(x > y)) { 53 x = y + phys_base; 54 55 if (y >= KERNEL_IMAGE_SIZE) 56 return false; 57 } else { 58 x = y + (__START_KERNEL_map - PAGE_OFFSET); 59 60 /* carry flag will be set if starting x was >= PAGE_OFFSET */ 61 if ((x > y) || !phys_addr_valid(x)) 62 return false; 63 } 64 65 return pfn_valid(x >> PAGE_SHIFT); 66 } 67 EXPORT_SYMBOL(__virt_addr_valid); 68 69 #else 70 71 #ifdef CONFIG_DEBUG_VIRTUAL 72 unsigned long __phys_addr(unsigned long x) 73 { 74 unsigned long phys_addr = x - PAGE_OFFSET; 75 /* VMALLOC_* aren't constants */ 76 VIRTUAL_BUG_ON(x < PAGE_OFFSET); 77 VIRTUAL_BUG_ON(__vmalloc_start_set && is_vmalloc_addr((void *) x)); 78 /* max_low_pfn is set early, but not _that_ early */ 79 if (max_low_pfn) { 80 VIRTUAL_BUG_ON((phys_addr >> PAGE_SHIFT) > max_low_pfn); 81 BUG_ON(slow_virt_to_phys((void *)x) != phys_addr); 82 } 83 return phys_addr; 84 } 85 EXPORT_SYMBOL(__phys_addr); 86 #endif 87 88 bool __virt_addr_valid(unsigned long x) 89 { 90 if (x < PAGE_OFFSET) 91 return false; 92 if (__vmalloc_start_set && is_vmalloc_addr((void *) x)) 93 return false; 94 if (x >= FIXADDR_START) 95 return false; 96 return pfn_valid((x - PAGE_OFFSET) >> PAGE_SHIFT); 97 } 98 EXPORT_SYMBOL(__virt_addr_valid); 99 100 #endif /* CONFIG_X86_64 */ 101