config/kernel-blk-queue-discard.m4

   1 dnl #
   2 dnl # 2.6.32 API change
   3 dnl # Discard requests were moved to the normal I/O path.
   4 dnl #
   5 AC_DEFUN([ZFS_AC_KERNEL_BLK_QUEUE_DISCARD], [
   6         AC_MSG_CHECKING([whether blk_queue_discard() is available])
   7         tmp_flags="$EXTRA_KCFLAGS"
   8         EXTRA_KCFLAGS="-Wno-unused-but-set-variable"
   9         ZFS_LINUX_TRY_COMPILE([
  10                 #include <linux/blkdev.h>
  11         ],[
  12                 struct request_queue *q = NULL;
  13                 (void) blk_queue_discard(q);
  14         ],[
  15                 AC_MSG_RESULT(yes)
  16                 AC_DEFINE(HAVE_BLK_QUEUE_DISCARD, 1,
  17                           [blk_queue_discard() is available])
  18         ],[
  19                 AC_MSG_RESULT(no)
  20         ])
  21         EXTRA_KCFLAGS="$tmp_flags"
  22 ])