1 files changed, 64 insertions, 0 deletions
diff --git a/config/kernel-shrink.m4 b/config/kernel-shrink.m4
new file mode 100644
index 000000000..ea748c974
--- /dev/null
+++ b/config/kernel-shrink.m4
@@ -0,0 +1,64 @@
+dnl #
+dnl # 3.1 API change
+dnl # The super_block structure now stores a per-filesystem shrinker.
+dnl # This interface is preferable because it can be used to specifically
+dnl # target only the zfs filesystem for pruning.
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_SHRINK], [
+	AC_MSG_CHECKING([whether super_block has s_shrink])
+	ZFS_LINUX_TRY_COMPILE([
+		#include <linux/fs.h>
+	],[
+		int (*shrink)(struct shrinker *, struct shrink_control *sc)
+			__attribute__ ((unused)) = NULL;
+		struct super_block sb __attribute__ ((unused)) = {
+			.s_shrink.shrink = shrink,
+			.s_shrink.seeks = DEFAULT_SEEKS,
+			.s_shrink.batch = 0,
+		};
+	],[
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_SHRINK, 1, [struct super_block has s_shrink])
+
+	],[
+		AC_MSG_RESULT(no)
+	])
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_NR_CACHED_OBJECTS], [
+	AC_MSG_CHECKING([whether sops->nr_cached_objects() exists])
+	ZFS_LINUX_TRY_COMPILE([
+		#include <linux/fs.h>
+	],[
+		int (*nr_cached_objects)(struct super_block *)
+			__attribute__ ((unused)) = NULL;
+		struct super_operations sops __attribute__ ((unused)) = {
+			.nr_cached_objects = nr_cached_objects,
+		};
+	],[
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_NR_CACHED_OBJECTS, 1,
+			[sops->nr_cached_objects() exists])
+	],[
+		AC_MSG_RESULT(no)
+	])
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_FREE_CACHED_OBJECTS], [
+	AC_MSG_CHECKING([whether sops->free_cached_objects() exists])
+	ZFS_LINUX_TRY_COMPILE([
+		#include <linux/fs.h>
+	],[
+		void (*free_cached_objects)(struct super_block *, int)
+			__attribute__ ((unused)) = NULL;
+		struct super_operations sops __attribute__ ((unused)) = {
+			.free_cached_objects = free_cached_objects,
+		};
+	],[
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_FREE_CACHED_OBJECTS, 1,
+			[sops->free_cached_objects() exists])
+	],[
+		AC_MSG_RESULT(no)
+	])
+])