include/asm-x86_64/unaligned.h

   1 #ifndef __X8664_UNALIGNED_H
   2 #define __X8664_UNALIGNED_H
   3
   4 /*
   5  * The x86-64 can do unaligned accesses itself.
   6  *
   7  * The strange macros are there to make sure these can't
   8  * be misused in a way that makes them not work on other
   9  * architectures where unaligned accesses aren't as simple.
  10  */
  11
  12 /**
  13  * get_unaligned - get value from possibly mis-aligned location
  14  * @ptr: pointer to value
  15  *
  16  * This macro should be used for accessing values larger in size than
  17  * single bytes at locations that are expected to be improperly aligned,
  18  * e.g. retrieving a u16 value from a location not u16-aligned.
  19  *
  20  * Note that unaligned accesses can be very expensive on some architectures.
  21  */
  22 #define get_unaligned(ptr) (*(ptr))
  23
  24 /**
  25  * put_unaligned - put value to a possibly mis-aligned location
  26  * @val: value to place
  27  * @ptr: pointer to location
  28  *
  29  * This macro should be used for placing values larger in size than
  30  * single bytes at locations that are expected to be improperly aligned,
  31  * e.g. writing a u16 value to a location not u16-aligned.
  32  *
  33  * Note that unaligned accesses can be very expensive on some architectures.
  34  */
  35 #define put_unaligned(val, ptr) ((void)( *(ptr) = (val) ))
  36
  37 #endif