Imported Upstream version 0.6.5.9

[mirror_zfs-debian.git] / config / kernel-blk-queue-unplug.m4

diff --git a/config/kernel-blk-queue-unplug.m4 b/config/kernel-blk-queue-unplug.m4
new file mode 100644 (file)
index 0000000..075fbcc
--- /dev/null
+++ b/config/kernel-blk-queue-unplug.m4
@@ -0,0 +1,44 @@
+dnl #
+dnl # 2.6.32-2.6.35 API - The BIO_RW_UNPLUG enum can be used as a hint
+dnl # to unplug the queue.
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_BLK_QUEUE_HAVE_BIO_RW_UNPLUG], [
+       AC_MSG_CHECKING([whether the BIO_RW_UNPLUG enum is available])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="${NO_UNUSED_BUT_SET_VARIABLE}"
+       ZFS_LINUX_TRY_COMPILE([
+               #include <linux/blkdev.h>
+       ],[
+               extern enum bio_rw_flags rw;
+
+               rw = BIO_RW_UNPLUG;
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_BLK_QUEUE_HAVE_BIO_RW_UNPLUG, 1,
+                         [BIO_RW_UNPLUG is available])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_BLK_QUEUE_HAVE_BLK_PLUG], [
+       AC_MSG_CHECKING([whether struct blk_plug is available])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="${NO_UNUSED_BUT_SET_VARIABLE}"
+       ZFS_LINUX_TRY_COMPILE([
+               #include <linux/blkdev.h>
+       ],[
+               struct blk_plug plug;
+
+               blk_start_plug(&plug);
+               blk_finish_plug(&plug);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_BLK_QUEUE_HAVE_BLK_PLUG, 1,
+                         [struct blk_plug is available])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])