config/kernel-blk-rq-bytes.m4

   1 dnl #
   2 dnl # 2.6.29 API change
   3 dnl # In the 2.6.29 kernel blk_rq_bytes() was available as a GPL-only symbol.
   4 dnl # So we need to check the symbol license as well.  As of 2.6.31 the
   5 dnl blk_rq_bytes() helper was changed to a static inline which we can use.
   6 dnl #
   7 AC_DEFUN([ZFS_AC_KERNEL_BLK_RQ_BYTES], [
   8         AC_MSG_CHECKING([whether blk_rq_bytes() is available])
   9         tmp_flags="$EXTRA_KCFLAGS"
  10         EXTRA_KCFLAGS="-Wno-unused-but-set-variable"
  11         ZFS_LINUX_TRY_COMPILE([
  12                 #include <linux/blkdev.h>
  13         ],[
  14                 struct request *req = NULL;
  15                 (void) blk_rq_bytes(req);
  16         ],[
  17                 AC_MSG_RESULT(yes)
  18                 AC_DEFINE(HAVE_BLK_RQ_BYTES, 1,
  19                           [blk_rq_bytes() is available])
  20         ],[
  21                 AC_MSG_RESULT(no)
  22         ])
  23
  24         AC_MSG_CHECKING([whether blk_rq_bytes() is GPL-only])
  25         ZFS_LINUX_TRY_COMPILE([
  26                 #include <linux/module.h>
  27                 #include <linux/blkdev.h>
  28
  29                 MODULE_LICENSE("CDDL");
  30         ],[
  31                 struct request *req = NULL;
  32                 (void) blk_rq_bytes(req);
  33         ],[
  34                 AC_MSG_RESULT(no)
  35         ],[
  36                 AC_MSG_RESULT(yes)
  37                 AC_DEFINE(HAVE_BLK_RQ_BYTES_GPL_ONLY, 1,
  38                           [blk_rq_bytes() is GPL-only])
  39         ])
  40         EXTRA_KCFLAGS="$tmp_flags"
  41 ])