@@ -109,3 +109,7 @@ config XFS_ASSERT_FATAL
 	  result in warnings.
 
 	  This behavior can be modified at runtime via sysfs.
+
+config XFS_LAYOUT
+	def_bool y
+	depends on EXPORTFS_BLOCK_OPS

@@ -135,3 +135,4 @@ xfs-$(CONFIG_XFS_POSIX_ACL)	+= xfs_acl.o
 xfs-$(CONFIG_SYSCTL)		+= xfs_sysctl.o
 xfs-$(CONFIG_COMPAT)		+= xfs_ioctl32.o
 xfs-$(CONFIG_EXPORTFS_BLOCK_OPS)	+= xfs_pnfs.o
+xfs-$(CONFIG_XFS_LAYOUT)	+= xfs_layout.o

@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2014 Christoph Hellwig.
+ */
+#include "xfs.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_sb.h"
+#include "xfs_mount.h"
+#include "xfs_inode.h"
+
+#include <linux/fs.h>
+
+/*
+ * Ensure that we do not have any outstanding pNFS layouts that can be used by
+ * clients to directly read from or write to this inode.  This must be called
+ * before every operation that can remove blocks from the extent map.
+ * Additionally we call it during the write operation, where aren't concerned
+ * about exposing unallocated blocks but just want to provide basic
+ * synchronization between a local writer and pNFS clients.  mmap writes would
+ * also benefit from this sort of synchronization, but due to the tricky locking
+ * rules in the page fault path we don't bother.
+ */
+int
+xfs_break_layouts(
+	struct inode		*inode,
+	uint			*iolock)
+{
+	struct xfs_inode	*ip = XFS_I(inode);
+	int			error;
+
+	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL));
+
+	while ((error = break_layout(inode, false) == -EWOULDBLOCK)) {
+		xfs_iunlock(ip, *iolock);
+		error = break_layout(inode, true);
+		*iolock = XFS_IOLOCK_EXCL;
+		xfs_ilock(ip, *iolock);
+	}
+
+	return error;
+}

@@ -0,0 +1,13 @@
+#ifndef _XFS_LAYOUT_H
+#define _XFS_LAYOUT_H 1
+
+#ifdef CONFIG_XFS_LAYOUT
+int xfs_break_layouts(struct inode *inode, uint *iolock);
+#else
+static inline int
+xfs_break_layouts(struct inode *inode, uint *iolock)
+{
+	return 0;
+}
+#endif /* CONFIG_XFS_LAYOUT */
+#endif /* _XFS_LAYOUT_H */

@@ -20,36 +20,6 @@
 #include "xfs_pnfs.h"
 
 /*
- * Ensure that we do not have any outstanding pNFS layouts that can be used by
- * clients to directly read from or write to this inode.  This must be called
- * before every operation that can remove blocks from the extent map.
- * Additionally we call it during the write operation, where aren't concerned
- * about exposing unallocated blocks but just want to provide basic
- * synchronization between a local writer and pNFS clients.  mmap writes would
- * also benefit from this sort of synchronization, but due to the tricky locking
- * rules in the page fault path we don't bother.
- */
-int
-xfs_break_layouts(
-	struct inode		*inode,
-	uint			*iolock)
-{
-	struct xfs_inode	*ip = XFS_I(inode);
-	int			error;
-
-	ASSERT(xfs_isilocked(ip, XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL));
-
-	while ((error = break_layout(inode, false) == -EWOULDBLOCK)) {
-		xfs_iunlock(ip, *iolock);
-		error = break_layout(inode, true);
-		*iolock = XFS_IOLOCK_EXCL;
-		xfs_ilock(ip, *iolock);
-	}
-
-	return error;
-}
-
-/*
  * Get a unique ID including its location so that the client can identify
  * the exported device.
  */

@@ -1,19 +1,13 @@
 #ifndef _XFS_PNFS_H
 #define _XFS_PNFS_H 1
 
+#include "xfs_layout.h"
+
 #ifdef CONFIG_EXPORTFS_BLOCK_OPS
 int xfs_fs_get_uuid(struct super_block *sb, u8 *buf, u32 *len, u64 *offset);
 int xfs_fs_map_blocks(struct inode *inode, loff_t offset, u64 length,
 		struct iomap *iomap, bool write, u32 *device_generation);
 int xfs_fs_commit_blocks(struct inode *inode, struct iomap *maps, int nr_maps,
 		struct iattr *iattr);
-
-int xfs_break_layouts(struct inode *inode, uint *iolock);
-#else
-static inline int
-xfs_break_layouts(struct inode *inode, uint *iolock)
-{
-	return 0;
-}
 #endif /* CONFIG_EXPORTFS_BLOCK_OPS */
 #endif /* _XFS_PNFS_H */

--