arch/arm/mm/physaddr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/bug.h>
   3 #include <linux/export.h>
   4 #include <linux/types.h>
   5 #include <linux/mmdebug.h>
   6 #include <linux/mm.h>
   7
   8 #include <asm/sections.h>
   9 #include <asm/memory.h>
  10 #include <asm/fixmap.h>
  11 #include <asm/dma.h>
  12
  13 #include "mm.h"
  14
  15 static inline bool __virt_addr_valid(unsigned long x)
  16 {
  17         /*
  18          * high_memory does not get immediately defined, and there
  19          * are early callers of __pa() against PAGE_OFFSET
  20          */
  21         if (!high_memory && x >= PAGE_OFFSET)
  22                 return true;
  23
  24         if (high_memory && x >= PAGE_OFFSET && x < (unsigned long)high_memory)
  25                 return true;
  26
  27         /*
  28          * MAX_DMA_ADDRESS is a virtual address that may not correspond to an
  29          * actual physical address. Enough code relies on __pa(MAX_DMA_ADDRESS)
  30          * that we just need to work around it and always return true.
  31          */
  32         if (x == MAX_DMA_ADDRESS)
  33                 return true;
  34
  35         return false;
  36 }
  37
  38 phys_addr_t __virt_to_phys(unsigned long x)
  39 {
  40         WARN(!__virt_addr_valid(x),
  41              "virt_to_phys used for non-linear address: %pK (%pS)\n",
  42              (void *)x, (void *)x);
  43
  44         return __virt_to_phys_nodebug(x);
  45 }
  46 EXPORT_SYMBOL(__virt_to_phys);
  47
  48 phys_addr_t __phys_addr_symbol(unsigned long x)
  49 {
  50         /* This is bounds checking against the kernel image only.
  51          * __pa_symbol should only be used on kernel symbol addresses.
  52          */
  53         VIRTUAL_BUG_ON(x < (unsigned long)KERNEL_START ||
  54                        x > (unsigned long)KERNEL_END);
  55
  56         return __pa_symbol_nodebug(x);
  57 }
  58 EXPORT_SYMBOL(__phys_addr_symbol);