Linux 3.10 compat: replace PDE()->data with PDE_DATA()

Linux kernel commit torvalds/linux@d9dda78b renamed PDE() to
PDE_DATA().  To handle this detect the prefered interface
and define a PDE_DATA() wrapper for consistency.

Signed-off-by: Yuxuan Shui <[email protected]>
Signed-off-by: Richard Yao <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Issue #257

config/spl-build.m4

@@ -34,6 +34,7 @@ AC_DEFUN([SPL_AC_CONFIG_KERNEL], [
 	SPL_AC_CTL_UNNUMBERED
 	SPL_AC_CTL_NAME
 	SPL_AC_VMALLOC_INFO
+	SPL_AC_PDE_DATA
 	SPL_AC_FLS64
 	SPL_AC_DEVICE_CREATE
 	SPL_AC_5ARGS_DEVICE_CREATE
@@ -1377,6 +1378,24 @@ AC_DEFUN([SPL_AC_VMALLOC_INFO], [
 	])
 ])
 
+dnl #
+dnl # 3.10 API change,
+dnl # PDE is replaced by PDE_DATA
+dnl #
+AC_DEFUN([SPL_AC_PDE_DATA], [
+	AC_MSG_CHECKING([whether PDE_DATA() is available])
+	SPL_LINUX_TRY_COMPILE_SYMBOL([
+		#include <linux/proc_fs.h>
+	], [
+		PDE_DATA(NULL);
+	], [PDE_DATA], [], [
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_PDE_DATA, 1, [yes])
+	],[
+		AC_MSG_RESULT(no)
+	])
+])
+
 dnl #
 dnl # 2.6.17 API change
 dnl # The helper functions first_online_pgdat(), next_online_pgdat(), and

module/spl/spl-kstat.c

@@ -33,6 +33,9 @@
 #endif
 
 #define SS_DEBUG_SUBSYS SS_KSTAT
+#ifndef HAVE_PDE_DATA
+#define PDE_DATA(x) (PDE(x)->data)
+#endif
 
 static spinlock_t kstat_lock;
 static struct list_head kstat_list;
@@ -359,7 +362,7 @@ proc_kstat_open(struct inode *inode, struct file *filp)
                 return rc;
 
         f = filp->private_data;
-        f->private = PDE(inode)->data;
+        f->private = PDE_DATA(inode);
 
         return rc;
 }