diff options
authorJ. Bruce Fields <bfields@redhat.com>2011-07-15 19:09:08 -0400
committerTrond Myklebust <Trond.Myklebust@netapp.com>2011-07-15 19:14:00 -0400
commit674e405b8b3310702fd43d314f5f432ec2cb9980 (patch)
parent94b134ac8e9965309e70684b504c53bca36338b4 (diff)
nfs: document nfsv4 sillyrename issues
Somebody working on this code asked what the deal was with NFSv4, since this comment notes that it's v2/v3's statelessness that requires sillyrename. Shouldn't hurt to document the answer. Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/nfs/unlink.c b/fs/nfs/unlink.c
index 8d6864c2a5fa..981298ce5124 100644
--- a/fs/nfs/unlink.c
+++ b/fs/nfs/unlink.c
@@ -501,6 +501,14 @@ nfs_async_rename(struct inode *old_dir, struct inode *new_dir,
* and only performs the unlink once the last reference to it is put.
* The final cleanup is done during dentry_iput.
+ *
+ * (Note: NFSv4 is stateful, and has opens, so in theory an NFSv4 server
+ * could take responsibility for keeping open files referenced. The server
+ * would also need to ensure that opened-but-deleted files were kept over
+ * reboots. However, we may not assume a server does so. (RFC 5661
+ * does provide an OPEN4_RESULT_PRESERVE_UNLINKED flag that a server can
+ * use to advertise that it does this; some day we may take advantage of
+ * it.))
nfs_sillyrename(struct inode *dir, struct dentry *dentry)