nfsd41: stateid handling

When sessions are used, stateful operation sequenceid and stateid handling
are not used. When sessions are used,  on the first open set the seqid to 1,
mark state confirmed and skip seqid processing.

When sessionas are used the stateid generation number is ignored when it is zero
whereas without sessions bad_stateid or stale stateid is returned.

Add flags to propagate session use to all stateful ops and down to
check_stateid_generation.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfsd4_has_session should return a boolean, not u32]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: pass nfsd4_compoundres * to nfsd4_process_open1]
[nfsd41: calculate HAS_SESSION in nfs4_preprocess_stateid_op]
[nfsd41: calculate HAS_SESSION in nfs4_preprocess_seqid_op]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/include/linux/nfsd/xdr4.h b/include/linux/nfsd/xdr4.h
index a0a2e83..b8b3dcb 100644
--- a/include/linux/nfsd/xdr4.h
+++ b/include/linux/nfsd/xdr4.h
@@ -56,6 +56,11 @@
 	u32			status;
 };
 
+static inline bool nfsd4_has_session(struct nfsd4_compound_state *cs)
+{
+	return cs->slot != NULL;
+}
+
 struct nfsd4_change_info {
 	u32		atomic;
 	u32		before_ctime_sec;
@@ -536,7 +541,8 @@
 extern __be32 nfsd4_destroy_session(struct svc_rqst *,
 		struct nfsd4_compound_state *,
 		struct nfsd4_destroy_session *);
-extern __be32 nfsd4_process_open1(struct nfsd4_open *open);
+extern __be32 nfsd4_process_open1(struct nfsd4_compound_state *,
+		struct nfsd4_open *open);
 extern __be32 nfsd4_process_open2(struct svc_rqst *rqstp,
 		struct svc_fh *current_fh, struct nfsd4_open *open);
 extern __be32 nfsd4_open_confirm(struct svc_rqst *rqstp,