/usr/src/zfs-0.6.5.6/config/kernel-blk-queue-flush.m4 is in zfs-dkms 0.6.5.6-0ubuntu8.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 | dnl #
dnl # 2.6.36 API change
dnl # In 2.6.36 kernels the blk_queue_ordered() interface has been
dnl # replaced by the simpler blk_queue_flush(). However, while the
dnl # old interface was available to all the new one is GPL-only.
dnl # Thus in addition to detecting if this function is available
dnl # we determine if it is GPL-only. If the GPL-only interface is
dnl # there we implement our own compatibility function, otherwise
dnl # we use the function. The hope is that long term this function
dnl # will be opened up.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_BLK_QUEUE_FLUSH], [
AC_MSG_CHECKING([whether blk_queue_flush() is available])
tmp_flags="$EXTRA_KCFLAGS"
EXTRA_KCFLAGS="${NO_UNUSED_BUT_SET_VARIABLE}"
ZFS_LINUX_TRY_COMPILE([
#include <linux/blkdev.h>
],[
struct request_queue *q = NULL;
(void) blk_queue_flush(q, REQ_FLUSH);
],[
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_BLK_QUEUE_FLUSH, 1,
[blk_queue_flush() is available])
],[
AC_MSG_RESULT(no)
])
AC_MSG_CHECKING([whether blk_queue_flush() is GPL-only])
ZFS_LINUX_TRY_COMPILE([
#include <linux/module.h>
#include <linux/blkdev.h>
MODULE_LICENSE("$ZFS_META_LICENSE");
],[
struct request_queue *q = NULL;
(void) blk_queue_flush(q, REQ_FLUSH);
],[
AC_MSG_RESULT(no)
],[
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_BLK_QUEUE_FLUSH_GPL_ONLY, 1,
[blk_queue_flush() is GPL-only])
])
EXTRA_KCFLAGS="$tmp_flags"
])
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