xfs: abstract block export operations from nfsd layouts

Instead of creeping pnfs layout configuration into filesystems, move the
definition of block-based export operations under a more abstract
configuration.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/Kconfig b/fs/Kconfig
index b8fcb41..4d2f921 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -67,6 +67,12 @@
 config EXPORTFS
 	tristate
 
+config EXPORTFS_BLOCK_OPS
+	bool "Enable filesystem export operations for block IO"
+	help
+	  This option enables the export operations for a filesystem to support
+	  external block IO.
+
 config FILE_LOCKING
 	bool "Enable POSIX file locking API" if EXPERT
 	default y
diff --git a/fs/nfsd/Kconfig b/fs/nfsd/Kconfig
index e64d1a3..47febcf 100644
--- a/fs/nfsd/Kconfig
+++ b/fs/nfsd/Kconfig
@@ -90,6 +90,7 @@
 	bool "NFSv4.1 server support for pNFS block layouts"
 	depends on NFSD_V4 && BLOCK
 	select NFSD_PNFS
+	select EXPORTFS_BLOCK_OPS
 	help
 	  This option enables support for the exporting pNFS block layouts
 	  in the kernel's NFS server. The pNFS block layout enables NFS
@@ -102,6 +103,7 @@
 	bool "NFSv4.1 server support for pNFS SCSI layouts"
 	depends on NFSD_V4 && BLOCK
 	select NFSD_PNFS
+	select EXPORTFS_BLOCK_OPS
 	help
 	  This option enables support for the exporting pNFS SCSI layouts
 	  in the kernel's NFS server. The pNFS SCSI layout enables NFS
diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
index 3542d94..52c2885 100644
--- a/fs/xfs/Makefile
+++ b/fs/xfs/Makefile
@@ -121,5 +121,4 @@
 xfs-$(CONFIG_XFS_POSIX_ACL)	+= xfs_acl.o
 xfs-$(CONFIG_SYSCTL)		+= xfs_sysctl.o
 xfs-$(CONFIG_COMPAT)		+= xfs_ioctl32.o
-xfs-$(CONFIG_NFSD_BLOCKLAYOUT)	+= xfs_pnfs.o
-xfs-$(CONFIG_NFSD_SCSILAYOUT)	+= xfs_pnfs.o
+xfs-$(CONFIG_EXPORTFS_BLOCK_OPS)	+= xfs_pnfs.o
diff --git a/fs/xfs/xfs_export.c b/fs/xfs/xfs_export.c
index a1b2dd8..fe1bfee 100644
--- a/fs/xfs/xfs_export.c
+++ b/fs/xfs/xfs_export.c
@@ -246,7 +246,7 @@
 	.fh_to_parent		= xfs_fs_fh_to_parent,
 	.get_parent		= xfs_fs_get_parent,
 	.commit_metadata	= xfs_fs_nfs_commit_metadata,
-#ifdef CONFIG_NFSD_BLOCKLAYOUT
+#ifdef CONFIG_EXPORTFS_BLOCK_OPS
 	.get_uuid		= xfs_fs_get_uuid,
 	.map_blocks		= xfs_fs_map_blocks,
 	.commit_blocks		= xfs_fs_commit_blocks,
diff --git a/fs/xfs/xfs_pnfs.h b/fs/xfs/xfs_pnfs.h
index 93f7485..e8339f7 100644
--- a/fs/xfs/xfs_pnfs.h
+++ b/fs/xfs/xfs_pnfs.h
@@ -1,7 +1,7 @@
 #ifndef _XFS_PNFS_H
 #define _XFS_PNFS_H 1
 
-#if defined(CONFIG_NFSD_BLOCKLAYOUT) || defined(CONFIG_NFSD_SCSILAYOUT)
+#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);
@@ -15,5 +15,5 @@
 {
 	return 0;
 }
-#endif /* CONFIG_NFSD_PNFS */
+#endif /* CONFIG_EXPORTFS_BLOCK_OPS */
 #endif /* _XFS_PNFS_H */