Line data    Source code

       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       37953 : bool __virt_addr_valid(unsigned long x)
      48             : {
      49       37953 :         unsigned long y = x - __START_KERNEL_map;
      50             : 
      51             :         /* use the carry flag to determine if x was < __START_KERNEL_map */
      52       37953 :         if (unlikely(x > y)) {
      53           4 :                 x = y + phys_base;
      54             : 
      55           4 :                 if (y >= KERNEL_IMAGE_SIZE)
      56             :                         return false;
      57             :         } else {
      58       37949 :                 x = y + (__START_KERNEL_map - PAGE_OFFSET);
      59             : 
      60             :                 /* carry flag will be set if starting x was >= PAGE_OFFSET */
      61       37949 :                 if ((x > y) || !phys_addr_valid(x))
      62             :                         return false;
      63             :         }
      64             : 
      65       37953 :         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 */