nfsd41: CREATE_EXCLUSIVE4_1

Implement the CREATE_EXCLUSIVE4_1 open mode conforming to
http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-26

This mode allows the client to atomically create a file
if it doesn't exist while setting some of its attributes.

It must be implemented if the server supports persistent
reply cache and/or pnfs.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

2 files changed, 11 insertions, 7 deletions

diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index ec3cd49b04f5..e3f0cbcbd0db 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -368,7 +368,13 @@ enum opentype4 {
 enum createmode4 {
         NFS4_CREATE_UNCHECKED = 0,
         NFS4_CREATE_GUARDED = 1,
-        NFS4_CREATE_EXCLUSIVE = 2
+        NFS4_CREATE_EXCLUSIVE = 2,
+        /*
+         * New to NFSv4.1. If session is persistent,
+         * GUARDED4 MUST be used. Otherwise, use
+         * EXCLUSIVE4_1 instead of EXCLUSIVE4.
+         */
+        NFS4_CREATE_EXCLUSIVE4_1 = 3
 };
 
 enum limit_by4 {
diff --git a/include/linux/nfsd/xdr4.h b/include/linux/nfsd/xdr4.h
index c07d8fe7bb07..f80d6013fdc3 100644
--- a/include/linux/nfsd/xdr4.h
+++ b/include/linux/nfsd/xdr4.h
@@ -219,10 +219,8 @@ struct nfsd4_open {
         u32             op_create;          /* request */
         u32             op_createmode;      /* request */
         u32             op_bmval[3];        /* request */
-        union {                             /* request */
-                struct iattr    iattr;                      /* UNCHECKED4,GUARDED4 */
-                nfs4_verifier   verf;                                /* EXCLUSIVE4 */
-        } u;
+        struct iattr    iattr;              /* UNCHECKED4, GUARDED4, EXCLUSIVE4_1 */
+        nfs4_verifier   verf;               /* EXCLUSIVE4 */
         clientid_t      op_clientid;        /* request */
         struct xdr_netobj op_owner;           /* request */
         u32             op_seqid;           /* request */
@@ -236,8 +234,8 @@ struct nfsd4_open {
         struct nfs4_stateowner *op_stateowner; /* used during processing */
         struct nfs4_acl *op_acl;
 };
-#define op_iattr        u.iattr
-#define op_verf         u.verf
+#define op_iattr        iattr
+#define op_verf         verf
 
 struct nfsd4_open_confirm {
         stateid_t       oc_req_stateid          /* request */;