[PATCH 08/21] nfs: enable swap on NFS

Now that NFS can handle swap cache pages, add a swapfile method to allow
swapping over NFS.

NOTE: this dummy method is obviously not enough to make it safe.
A more complete version of the nfs_swapfile() function will be present
in the next VM deadlock avoidance patches.

Signed-off-by: Peter Zijlstra <redacted>
CC: Trond Myklebust <redacted>
---
 fs/nfs/file.c |    6 ++++++
 1 file changed, 6 insertions(+)

Index: linux-2.6/fs/nfs/file.c
===================================================================

--- linux-2.6.orig/fs/nfs/file.c
+++ linux-2.6/fs/nfs/file.c

@@ -321,6 +321,11 @@ static int nfs_release_page(struct page 
 		return 0;
 }
 
+static int nfs_swapfile(struct address_space *mapping, int enable)
+{
+	return 0;
+}
+
 const struct address_space_operations nfs_file_aops = {
 	.readpage = nfs_readpage,
 	.readpages = nfs_readpages,

@@ -334,6 +339,7 @@ const struct address_space_operations nf
 #ifdef CONFIG_NFS_DIRECTIO
 	.direct_IO = nfs_direct_IO,
 #endif
+	.swapfile = nfs_swapfile,
 };
 
 /* 

--