Fix build failures on PaX/GRSecurity patched kernels

Gentoo Hardened kernels include the PaX/GRSecurity patches. They use a
dialect of C that relies on a GCC plugin. In particular, struct
file_operations has been marked do_const in the PaX/GRSecurity dialect,
which causes GCC to consider all instances of it as const. This caused
failures in the autotools checks and the ZFS source code.

To address this, we modify the autotools checks to take into account
differences between the PaX C dialect and the regular C dialect. We also
modify struct zfs_acl's z_ops member to be a pointer to a function
pointer table. Lastly, we modify zpl_put_link() to address a PaX change
to the function prototype of nd_get_link().  This avoids compiler errors
in the PaX/GRSecurity dialect.

Note that the change in zpl_put_link() causes a warning that becomes a
build failure when debugging is enabled. Fixing that warning requires
ryao/spl@5ca50ef459c59bc74b7a7cd3af7311da2b1cd2c3.

Signed-off-by: Richard Yao <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #484

7 files changed, 640 insertions, 40 deletions

diff --git a/config/kernel-evict-inode.m4 b/config/kernel-evict-inode.m4
index 0700792f9..683cedb6d 100644
--- a/config/kernel-evict-inode.m4
+++ b/config/kernel-evict-inode.m4
@@ -7,12 +7,12 @@ AC_DEFUN([ZFS_AC_KERNEL_EVICT_INODE], [
 	AC_MSG_CHECKING([whether sops->evict_inode() exists])
 	ZFS_LINUX_TRY_COMPILE([
 		#include <linux/fs.h>
-	],[
-		void (*evict_inode) (struct inode *) = NULL;
-		struct super_operations sops __attribute__ ((unused)) = {
+		void evict_inode (struct inode * t) { return; }
+		static struct super_operations sops __attribute__ ((unused)) = {
 			.evict_inode = evict_inode,
 		};
 	],[
+	],[
 		AC_MSG_RESULT(yes)
 		AC_DEFINE(HAVE_EVICT_INODE, 1, [sops->evict_inode() exists])
 	],[
diff --git a/config/kernel-fallocate.m4 b/config/kernel-fallocate.m4
index d551276c7..6ac5ae65c 100644
--- a/config/kernel-fallocate.m4
+++ b/config/kernel-fallocate.m4
@@ -39,10 +39,31 @@ AC_DEFUN([ZFS_AC_KERNEL_INODE_FALLOCATE], [
 ])
 
 dnl #
+dnl # PaX Linux 2.6.38 - 3.x API
+dnl #
+AC_DEFUN([ZFS_AC_PAX_KERNEL_FILE_FALLOCATE], [
+	AC_MSG_CHECKING([whether fops->fallocate() exists])
+	ZFS_LINUX_TRY_COMPILE([
+		#include <linux/fs.h>
+	],[
+		long (*fallocate) (struct file *, int, loff_t, loff_t) = NULL;
+		struct file_operations_no_const fops __attribute__ ((unused)) = {
+			.fallocate = fallocate,
+		};
+	],[
+		AC_MSG_RESULT(yes)
+		AC_DEFINE(HAVE_FILE_FALLOCATE, 1, [fops->fallocate() exists])
+	],[
+		AC_MSG_RESULT(no)
+	])
+])
+
+dnl #
 dnl # The fallocate callback was moved from the inode_operations
 dnl # structure to the file_operations structure.
 dnl #
 AC_DEFUN([ZFS_AC_KERNEL_FALLOCATE], [
 	ZFS_AC_KERNEL_FILE_FALLOCATE
 	ZFS_AC_KERNEL_INODE_FALLOCATE
+	ZFS_AC_PAX_KERNEL_FILE_FALLOCATE
 ])
diff --git a/config/kernel-fsync.m4 b/config/kernel-fsync.m4
index 862b89782..ca00d93be 100644
--- a/config/kernel-fsync.m4
+++ b/config/kernel-fsync.m4
@@ -37,7 +37,7 @@ AC_DEFUN([ZFS_AC_KERNEL_FSYNC_WITHOUT_DENTRY], [
 ])
 
 dnl #
-dnl # Linux 3.1 -x 3.x API
+dnl # Linux 3.1 - 3.x API
 dnl #
 AC_DEFUN([ZFS_AC_KERNEL_FSYNC_RANGE], [
 	ZFS_LINUX_TRY_COMPILE([
@@ -55,9 +55,69 @@ AC_DEFUN([ZFS_AC_KERNEL_FSYNC_RANGE], [
 	])
 ])
 
+dnl #
+dnl # PaX Linux 2.6.x - 2.6.34 API
+dnl #
+AC_DEFUN([ZFS_AC_PAX_KERNEL_FSYNC_WITH_DENTRY], [
+	ZFS_LINUX_TRY_COMPILE([
+		#include <linux/fs.h>
+	],[
+		int (*fsync) (struct file *, struct dentry *, int) = NULL;
+		file_operations_no_const fops __attribute__ ((unused));
+
+		fops.fsync = fsync;
+	],[
+		AC_MSG_RESULT([dentry])
+		AC_DEFINE(HAVE_FSYNC_WITH_DENTRY, 1,
+			[fops->fsync() with dentry])
+	],[
+	])
+])
+
+dnl #
+dnl # PaX Linux 2.6.35 - Linux 3.0 API
+dnl #
+AC_DEFUN([ZFS_AC_PAX_KERNEL_FSYNC_WITHOUT_DENTRY], [
+	ZFS_LINUX_TRY_COMPILE([
+		#include <linux/fs.h>
+	],[
+		int (*fsync) (struct file *, int) = NULL;
+		file_operations_no_const fops __attribute__ ((unused));
+
+		fops.fsync = fsync;
+	],[
+		AC_MSG_RESULT([no dentry])
+		AC_DEFINE(HAVE_FSYNC_WITHOUT_DENTRY, 1,
+			[fops->fsync() without dentry])
+	],[
+	])
+])
+
+dnl #
+dnl # PaX Linux 3.1 - 3.x API
+dnl #
+AC_DEFUN([ZFS_AC_PAX_KERNEL_FSYNC_RANGE], [
+	ZFS_LINUX_TRY_COMPILE([
+		#include <linux/fs.h>
+	],[
+		int (*fsync) (struct file *, loff_t, loff_t, int) = NULL;
+		file_operations_no_const fops __attribute__ ((unused));
+
+		fops.fsync = fsync;
+	],[
+		AC_MSG_RESULT([range])
+		AC_DEFINE(HAVE_FSYNC_RANGE, 1,
+			[fops->fsync() with range])
+	],[
+	])
+])
+
 AC_DEFUN([ZFS_AC_KERNEL_FSYNC], [
 	AC_MSG_CHECKING([whether fops->fsync() wants])
 	ZFS_AC_KERNEL_FSYNC_WITH_DENTRY
 	ZFS_AC_KERNEL_FSYNC_WITHOUT_DENTRY
 	ZFS_AC_KERNEL_FSYNC_RANGE
+	ZFS_AC_PAX_KERNEL_FSYNC_WITH_DENTRY
+	ZFS_AC_PAX_KERNEL_FSYNC_WITHOUT_DENTRY
+	ZFS_AC_PAX_KERNEL_FSYNC_RANGE
 ])
diff --git a/configure b/configure
index 60b844d83..245113ea4 100755
--- a/configure
+++ b/configure
@@ -15530,8 +15530,69 @@ fi
 
 
 
-	{ $as_echo "$as_me:$LINENO: checking whether sops->evict_inode() exists" >&5
-$as_echo_n "checking whether sops->evict_inode() exists... " >&6; }
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/fs.h>
+
+int
+main (void)
+{
+
+		int (*fsync) (struct file *, struct dentry *, int) = NULL;
+		file_operations_no_const fops __attribute__ ((unused));
+
+		fops.fsync = fsync;
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: dentry" >&5
+$as_echo "dentry" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_FSYNC_WITH_DENTRY 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+
+
+fi
+
+	rm -Rf build
+
+
+
+
 
 
 cat confdefs.h - <<_ACEOF >conftest.c
@@ -15548,11 +15609,142 @@ int
 main (void)
 {
 
-		void (*evict_inode) (struct inode *) = NULL;
-		struct super_operations sops __attribute__ ((unused)) = {
+		int (*fsync) (struct file *, int) = NULL;
+		file_operations_no_const fops __attribute__ ((unused));
+
+		fops.fsync = fsync;
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: no dentry" >&5
+$as_echo "no dentry" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_FSYNC_WITHOUT_DENTRY 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+
+
+fi
+
+	rm -Rf build
+
+
+
+
+
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/fs.h>
+
+int
+main (void)
+{
+
+		int (*fsync) (struct file *, loff_t, loff_t, int) = NULL;
+		file_operations_no_const fops __attribute__ ((unused));
+
+		fops.fsync = fsync;
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: range" >&5
+$as_echo "range" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_FSYNC_RANGE 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+
+
+fi
+
+	rm -Rf build
+
+
+
+
+
+	{ $as_echo "$as_me:$LINENO: checking whether sops->evict_inode() exists" >&5
+$as_echo_n "checking whether sops->evict_inode() exists... " >&6; }
+
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/fs.h>
+		void evict_inode (struct inode * t) { return; }
+		static struct super_operations sops __attribute__ ((unused)) = {
 			.evict_inode = evict_inode,
 		};
 
+int
+main (void)
+{
+
+
   ;
   return 0;
 }
@@ -15873,6 +16065,74 @@ fi
 
 
 
+	{ $as_echo "$as_me:$LINENO: checking whether fops->fallocate() exists" >&5
+$as_echo_n "checking whether fops->fallocate() exists... " >&6; }
+
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/fs.h>
+
+int
+main (void)
+{
+
+		long (*fallocate) (struct file *, int, loff_t, loff_t) = NULL;
+		struct file_operations_no_const fops __attribute__ ((unused)) = {
+			.fallocate = fallocate,
+		};
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: yes" >&5
+$as_echo "yes" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_FILE_FALLOCATE 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+		{ $as_echo "$as_me:$LINENO: result: no" >&5
+$as_echo "no" >&6; }
+
+
+
+fi
+
+	rm -Rf build
+
+
+
+
 
 	{ $as_echo "$as_me:$LINENO: checking whether iops->create()/mkdir()/mknod() take umode_t" >&5
 $as_echo_n "checking whether iops->create()/mkdir()/mknod() take umode_t... " >&6; }
@@ -21797,8 +22057,69 @@ fi
 
 
 
-	{ $as_echo "$as_me:$LINENO: checking whether sops->evict_inode() exists" >&5
-$as_echo_n "checking whether sops->evict_inode() exists... " >&6; }
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/fs.h>
+
+int
+main (void)
+{
+
+		int (*fsync) (struct file *, struct dentry *, int) = NULL;
+		file_operations_no_const fops __attribute__ ((unused));
+
+		fops.fsync = fsync;
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: dentry" >&5
+$as_echo "dentry" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_FSYNC_WITH_DENTRY 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+
+
+fi
+
+	rm -Rf build
+
+
+
+
 
 
 cat confdefs.h - <<_ACEOF >conftest.c
@@ -21815,11 +22136,142 @@ int
 main (void)
 {
 
-		void (*evict_inode) (struct inode *) = NULL;
-		struct super_operations sops __attribute__ ((unused)) = {
+		int (*fsync) (struct file *, int) = NULL;
+		file_operations_no_const fops __attribute__ ((unused));
+
+		fops.fsync = fsync;
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: no dentry" >&5
+$as_echo "no dentry" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_FSYNC_WITHOUT_DENTRY 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+
+
+fi
+
+	rm -Rf build
+
+
+
+
+
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/fs.h>
+
+int
+main (void)
+{
+
+		int (*fsync) (struct file *, loff_t, loff_t, int) = NULL;
+		file_operations_no_const fops __attribute__ ((unused));
+
+		fops.fsync = fsync;
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: range" >&5
+$as_echo "range" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_FSYNC_RANGE 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+
+
+
+fi
+
+	rm -Rf build
+
+
+
+
+
+	{ $as_echo "$as_me:$LINENO: checking whether sops->evict_inode() exists" >&5
+$as_echo_n "checking whether sops->evict_inode() exists... " >&6; }
+
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/fs.h>
+		void evict_inode (struct inode * t) { return; }
+		static struct super_operations sops __attribute__ ((unused)) = {
 			.evict_inode = evict_inode,
 		};
 
+int
+main (void)
+{
+
+
   ;
   return 0;
 }
@@ -22140,6 +22592,74 @@ fi
 
 
 
+	{ $as_echo "$as_me:$LINENO: checking whether fops->fallocate() exists" >&5
+$as_echo_n "checking whether fops->fallocate() exists... " >&6; }
+
+
+cat confdefs.h - <<_ACEOF >conftest.c
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+
+		#include <linux/fs.h>
+
+int
+main (void)
+{
+
+		long (*fallocate) (struct file *, int, loff_t, loff_t) = NULL;
+		struct file_operations_no_const fops __attribute__ ((unused)) = {
+			.fallocate = fallocate,
+		};
+
+  ;
+  return 0;
+}
+
+_ACEOF
+
+
+	rm -Rf build && mkdir -p build
+	echo "obj-m := conftest.o" >build/Makefile
+	if { ac_try='cp conftest.c build && make modules -C $LINUX_OBJ EXTRA_CFLAGS="-Werror-implicit-function-declaration $EXTRA_KCFLAGS" $ARCH_UM M=$PWD/build'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } >/dev/null && { ac_try='test -s build/conftest.o'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+		{ $as_echo "$as_me:$LINENO: result: yes" >&5
+$as_echo "yes" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_FILE_FALLOCATE 1
+_ACEOF
+
+
+else
+  $as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+		{ $as_echo "$as_me:$LINENO: result: no" >&5
+$as_echo "no" >&6; }
+
+
+
+fi
+
+	rm -Rf build
+
+
+
+
 
 	{ $as_echo "$as_me:$LINENO: checking whether iops->create()/mkdir()/mknod() take umode_t" >&5
 $as_echo_n "checking whether iops->create()/mkdir()/mknod() take umode_t... " >&6; }
diff --git a/include/sys/zfs_acl.h b/include/sys/zfs_acl.h
index b6ed4390f..11fc3351e 100644
--- a/include/sys/zfs_acl.h
+++ b/include/sys/zfs_acl.h
@@ -165,7 +165,7 @@ typedef struct zfs_acl {
 	uint64_t	z_hints;	/* ACL hints (ZFS_INHERIT_ACE ...) */
 	zfs_acl_node_t	*z_curr_node;	/* current node iterator is handling */
 	list_t		z_acl;		/* chunks of ACE data */
-	acl_ops_t	z_ops;		/* ACL operations */
+	acl_ops_t	*z_ops;		/* ACL operations */
 } zfs_acl_t;
 
 typedef struct acl_locator_cb {
diff --git a/module/zfs/zfs_acl.c b/module/zfs/zfs_acl.c
index 40f792b6c..df690b364 100644
--- a/module/zfs/zfs_acl.c
+++ b/module/zfs/zfs_acl.c
@@ -457,9 +457,9 @@ zfs_acl_alloc(int vers)
 	    offsetof(zfs_acl_node_t, z_next));
 	aclp->z_version = vers;
 	if (vers == ZFS_ACL_VERSION_FUID)
-		aclp->z_ops = zfs_acl_fuid_ops;
+		aclp->z_ops = &zfs_acl_fuid_ops;
 	else
-		aclp->z_ops = zfs_acl_v0_ops;
+		aclp->z_ops = &zfs_acl_v0_ops;
 	return (aclp);
 }
 
@@ -609,17 +609,17 @@ zfs_acl_next_ace(zfs_acl_t *aclp, void *start, uint64_t *who,
 		/*
 		 * Make sure we don't overstep our bounds
 		 */
-		ace_size = aclp->z_ops.ace_size(acep);
+		ace_size = aclp->z_ops->ace_size(acep);
 
 		if (((caddr_t)acep + ace_size) >
 		    ((caddr_t)aclnode->z_acldata + aclnode->z_size)) {
 			return (NULL);
 		}
 
-		*iflags = aclp->z_ops.ace_flags_get(acep);
-		*type = aclp->z_ops.ace_type_get(acep);
-		*access_mask = aclp->z_ops.ace_mask_get(acep);
-		*who = aclp->z_ops.ace_who_get(acep);
+		*iflags = aclp->z_ops->ace_flags_get(acep);
+		*type = aclp->z_ops->ace_type_get(acep);
+		*access_mask = aclp->z_ops->ace_mask_get(acep);
+		*who = aclp->z_ops->ace_who_get(acep);
 		aclp->z_next_ace = (caddr_t)aclp->z_next_ace + ace_size;
 		aclnode->z_ace_idx++;
 
@@ -698,7 +698,7 @@ zfs_copy_ace_2_fuid(zfs_sb_t *zsb, umode_t obj_mode, zfs_acl_t *aclp,
 		}
 
 		aceptr = (zfs_ace_t *)((caddr_t)aceptr +
-		    aclp->z_ops.ace_size(aceptr));
+		    aclp->z_ops->ace_size(aceptr));
 	}
 
 	*size = (caddr_t)aceptr - (caddr_t)z_acl;
@@ -824,7 +824,7 @@ zfs_acl_xform(znode_t *zp, zfs_acl_t *aclp, cred_t *cr)
 
 	newaclnode = zfs_acl_node_alloc(aclp->z_acl_count *
 	    sizeof (zfs_object_ace_t));
-	aclp->z_ops = zfs_acl_fuid_ops;
+	aclp->z_ops = &zfs_acl_fuid_ops;
 	VERIFY(zfs_copy_ace_2_fuid(ZTOZSB(zp), ZTOI(zp)->i_mode,
 	    aclp, oldaclp, newaclnode->z_acldata, aclp->z_acl_count,
 	    &newaclnode->z_size, NULL, cr) == 0);
@@ -868,12 +868,12 @@ zfs_set_ace(zfs_acl_t *aclp, void *acep, uint32_t access_mask,
 {
 	uint16_t type = entry_type & ACE_TYPE_FLAGS;
 
-	aclp->z_ops.ace_mask_set(acep, access_mask);
-	aclp->z_ops.ace_type_set(acep, access_type);
-	aclp->z_ops.ace_flags_set(acep, entry_type);
+	aclp->z_ops->ace_mask_set(acep, access_mask);
+	aclp->z_ops->ace_type_set(acep, access_type);
+	aclp->z_ops->ace_flags_set(acep, entry_type);
 	if ((type != ACE_OWNER && type != OWNING_GROUP &&
 	    type != ACE_EVERYONE))
-		aclp->z_ops.ace_who_set(acep, fuid);
+		aclp->z_ops->ace_who_set(acep, fuid);
 }
 
 /*
@@ -1454,7 +1454,7 @@ zfs_acl_chmod(zfs_sb_t *zsb, uint64_t mode, zfs_acl_t *aclp)
 	uint16_t	iflags, type;
 	uint32_t	access_mask;
 	zfs_acl_node_t	*newnode;
-	size_t		abstract_size = aclp->z_ops.ace_abstract_size();
+	size_t		abstract_size = aclp->z_ops->ace_abstract_size();
 	void		*zacep;
 	uint32_t	owner, group, everyone;
 	uint32_t	deny1, deny2, allow0;
@@ -1530,7 +1530,7 @@ zfs_acl_chmod(zfs_sb_t *zsb, uint64_t mode, zfs_acl_t *aclp)
 			}
 		}
 		zfs_set_ace(aclp, zacep, access_mask, type, who, iflags);
-		ace_size = aclp->z_ops.ace_size(acep);
+		ace_size = aclp->z_ops->ace_size(acep);
 		zacep = (void *)((uintptr_t)zacep + ace_size);
 		new_count++;
 		new_bytes += ace_size;
@@ -1570,12 +1570,12 @@ zfs_acl_chmod_setattr(znode_t *zp, zfs_acl_t **aclp, uint64_t mode)
 static void
 zfs_restricted_update(zfs_sb_t *zsb, zfs_acl_t *aclp, void *acep)
 {
-	uint32_t mask = aclp->z_ops.ace_mask_get(acep);
+	uint32_t mask = aclp->z_ops->ace_mask_get(acep);
 
 	if ((zsb->z_acl_inherit == ZFS_ACL_RESTRICTED) &&
-	    (aclp->z_ops.ace_type_get(acep) == ALLOW)) {
+	    (aclp->z_ops->ace_type_get(acep) == ALLOW)) {
 		mask &= ~RESTRICTED_CLEAR;
-		aclp->z_ops.ace_mask_set(acep, mask);
+		aclp->z_ops->ace_mask_set(acep, mask);
 	}
 }
 
@@ -1640,7 +1640,7 @@ zfs_acl_inherit(zfs_sb_t *zsb, umode_t obj_mode, zfs_acl_t *paclp,
 		if (noallow && type == ALLOW)
 			continue;
 
-		ace_size = aclp->z_ops.ace_size(pacep);
+		ace_size = aclp->z_ops->ace_size(pacep);
 
 		if (!zfs_ace_can_use(obj_mode, iflags))
 			continue;
@@ -1672,8 +1672,8 @@ zfs_acl_inherit(zfs_sb_t *zsb, umode_t obj_mode, zfs_acl_t *paclp,
 		/*
 		 * Copy special opaque data if any
 		 */
-		if ((data1sz = paclp->z_ops.ace_data(pacep, &data1)) != 0) {
-			VERIFY((data2sz = aclp->z_ops.ace_data(acep,
+		if ((data1sz = paclp->z_ops->ace_data(pacep, &data1)) != 0) {
+			VERIFY((data2sz = aclp->z_ops->ace_data(acep,
 			    &data2)) == data1sz);
 			bcopy(data1, data2, data2sz);
 		}
@@ -1681,14 +1681,14 @@ zfs_acl_inherit(zfs_sb_t *zsb, umode_t obj_mode, zfs_acl_t *paclp,
 		aclp->z_acl_count++;
 		aclnode->z_ace_count++;
 		aclp->z_acl_bytes += aclnode->z_size;
-		newflags = aclp->z_ops.ace_flags_get(acep);
+		newflags = aclp->z_ops->ace_flags_get(acep);
 
 		if (vdir)
 			aclp->z_hints |= ZFS_INHERIT_ACE;
 
 		if ((iflags & ACE_NO_PROPAGATE_INHERIT_ACE) || !vdir) {
 			newflags &= ~ALL_INHERIT;
-			aclp->z_ops.ace_flags_set(acep,
+			aclp->z_ops->ace_flags_set(acep,
 			    newflags|ACE_INHERITED_ACE);
 			zfs_restricted_update(zsb, aclp, acep);
 			continue;
@@ -1703,11 +1703,11 @@ zfs_acl_inherit(zfs_sb_t *zsb, umode_t obj_mode, zfs_acl_t *paclp,
 		if ((iflags & (ACE_FILE_INHERIT_ACE |
 		    ACE_DIRECTORY_INHERIT_ACE)) == ACE_FILE_INHERIT_ACE) {
 			newflags |= ACE_INHERIT_ONLY_ACE;
-			aclp->z_ops.ace_flags_set(acep,
+			aclp->z_ops->ace_flags_set(acep,
 			    newflags|ACE_INHERITED_ACE);
 		} else {
 			newflags &= ~ACE_INHERIT_ONLY_ACE;
-			aclp->z_ops.ace_flags_set(acep,
+			aclp->z_ops->ace_flags_set(acep,
 			    newflags|ACE_INHERITED_ACE);
 		}
 	}
diff --git a/module/zfs/zpl_inode.c b/module/zfs/zpl_inode.c
index 1f6169b75..ea8c309ac 100644
--- a/module/zfs/zpl_inode.c
+++ b/module/zfs/zpl_inode.c
@@ -294,9 +294,8 @@ zpl_follow_link(struct dentry *dentry, struct nameidata *nd)
 static void
 zpl_put_link(struct dentry *dentry, struct nameidata *nd, void *ptr)
 {
-	char *link;
+	const char *link = nd_get_link(nd);
 
-	link = nd_get_link(nd);
 	if (!IS_ERR(link))
 		kmem_free(link, MAXPATHLEN);
 }