#include <linux/smp_lock.h>
 #include <linux/namei.h>
 #include <linux/mount.h>
+#include <linux/module.h>
 
 #include "nfs4_fs.h"
 #include "delegation.h"
        spin_unlock(&tbl->slot_tbl_lock);
 
        slot = tbl->slots + slotid;
+       args->sa_session = session;
        args->sa_slotid = slotid;
        args->sa_cache_this = cache_reply;
 
        dprintk("<-- %s slotid=%d seqid=%d\n", __func__, slotid, slot->seq_nr);
 
+       res->sr_session = session;
        res->sr_slotid = slotid;
        res->sr_renewal_time = jiffies;
        /*
 }
 
 #ifdef CONFIG_NFS_V4_1
+/*
+ * nfs4_proc_exchange_id()
+ *
+ * Since the clientid has expired, all compounds using sessions
+ * associated with the stale clientid will be returning
+ * NFS4ERR_BADSESSION in the sequence operation, and will therefore
+ * be in some phase of session reset.
+ */
+static int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred)
+{
+       nfs4_verifier verifier;
+       struct nfs41_exchange_id_args args = {
+               .client = clp,
+               .flags = clp->cl_exchange_flags,
+       };
+       struct nfs41_exchange_id_res res = {
+               .client = clp,
+       };
+       int status;
+       struct rpc_message msg = {
+               .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_EXCHANGE_ID],
+               .rpc_argp = &args,
+               .rpc_resp = &res,
+               .rpc_cred = cred,
+       };
+       __be32 *p;
+
+       dprintk("--> %s\n", __func__);
+       BUG_ON(clp == NULL);
+       p = (u32 *)verifier.data;
+       *p++ = htonl((u32)clp->cl_boot_time.tv_sec);
+       *p = htonl((u32)clp->cl_boot_time.tv_nsec);
+       args.verifier = &verifier;
+
+       while (1) {
+               args.id_len = scnprintf(args.id, sizeof(args.id),
+                                       "%s/%s %u",
+                                       clp->cl_ipaddr,
+                                       rpc_peeraddr2str(clp->cl_rpcclient,
+                                                        RPC_DISPLAY_ADDR),
+                                       clp->cl_id_uniquifier);
+
+               status = rpc_call_sync(clp->cl_rpcclient, &msg, 0);
+
+               if (status != NFS4ERR_CLID_INUSE)
+                       break;
+
+               if (signalled())
+                       break;
+
+               if (++clp->cl_id_uniquifier == 0)
+                       break;
+       }
+
+       dprintk("<-- %s status= %d\n", __func__, status);
+       return status;
+}
+
 /* Destroy the slot table */
 static void nfs4_destroy_slot_table(struct nfs4_session *session)
 {
 
                                (0)
 
 #if defined(CONFIG_NFS_V4_1)
+#define encode_exchange_id_maxsz (op_encode_hdr_maxsz + \
+                               encode_verifier_maxsz + \
+                               1 /* co_ownerid.len */ + \
+                               XDR_QUADLEN(NFS4_EXCHANGE_ID_LEN) + \
+                               1 /* flags */ + \
+                               1 /* spa_how */ + \
+                               0 /* SP4_NONE (for now) */ + \
+                               1 /* zero implemetation id array */)
+#define decode_exchange_id_maxsz (op_decode_hdr_maxsz + \
+                               2 /* eir_clientid */ + \
+                               1 /* eir_sequenceid */ + \
+                               1 /* eir_flags */ + \
+                               1 /* spr_how */ + \
+                               0 /* SP4_NONE (for now) */ + \
+                               2 /* eir_server_owner.so_minor_id */ + \
+                               /* eir_server_owner.so_major_id<> */ \
+                               XDR_QUADLEN(NFS4_OPAQUE_LIMIT) + 1 + \
+                               /* eir_server_scope<> */ \
+                               XDR_QUADLEN(NFS4_OPAQUE_LIMIT) + 1 + \
+                               1 /* eir_server_impl_id array length */ + \
+                               0 /* ignored eir_server_impl_id contents */)
 #define encode_sequence_maxsz  0 /* stub */
 #define decode_sequence_maxsz  0 /* stub */
 #else /* CONFIG_NFS_V4_1 */
                                 decode_putfh_maxsz + \
                                 decode_lookup_maxsz + \
                                 decode_fs_locations_maxsz)
+#if defined(CONFIG_NFS_V4_1)
+#define NFS4_enc_exchange_id_sz \
+                               (compound_encode_hdr_maxsz + \
+                                encode_exchange_id_maxsz)
+#define NFS4_dec_exchange_id_sz \
+                               (compound_decode_hdr_maxsz + \
+                                decode_exchange_id_maxsz)
+#endif /* CONFIG_NFS_V4_1 */
 
 static const umode_t nfs_type2fmt[] = {
        [NF4BAD] = 0,
        hdr->replen += decode_delegreturn_maxsz;
 }
 
+#if defined(CONFIG_NFS_V4_1)
 /* NFSv4.1 operations */
+static void encode_exchange_id(struct xdr_stream *xdr,
+                              struct nfs41_exchange_id_args *args,
+                              struct compound_hdr *hdr)
+{
+       __be32 *p;
+
+       RESERVE_SPACE(4 + sizeof(args->verifier->data));
+       WRITE32(OP_EXCHANGE_ID);
+       WRITEMEM(args->verifier->data, sizeof(args->verifier->data));
+
+       encode_string(xdr, args->id_len, args->id);
+
+       RESERVE_SPACE(12);
+       WRITE32(args->flags);
+       WRITE32(0);     /* zero length state_protect4_a */
+       WRITE32(0);     /* zero length implementation id array */
+       hdr->nops++;
+       hdr->replen += decode_exchange_id_maxsz;
+}
+#endif /* CONFIG_NFS_V4_1 */
+
 static void encode_sequence(struct xdr_stream *xdr,
                            const struct nfs4_sequence_args *args,
                            struct compound_hdr *hdr)
        return 0;
 }
 
+#if defined(CONFIG_NFS_V4_1)
+/*
+ * EXCHANGE_ID request
+ */
+static int nfs4_xdr_enc_exchange_id(struct rpc_rqst *req, uint32_t *p,
+                                   struct nfs41_exchange_id_args *args)
+{
+       struct xdr_stream xdr;
+       struct compound_hdr hdr = {
+               .minorversion = args->client->cl_minorversion,
+       };
+
+       xdr_init_encode(&xdr, &req->rq_snd_buf, p);
+       encode_compound_hdr(&xdr, req, &hdr);
+       encode_exchange_id(&xdr, args, &hdr);
+       encode_nops(&hdr);
+       return 0;
+}
+#endif /* CONFIG_NFS_V4_1 */
+
 /*
  * START OF "GENERIC" DECODE ROUTINES.
  *   These may look a little ugly since they are imported from a "generic"
        return decode_op_hdr(xdr, OP_DELEGRETURN);
 }
 
+#if defined(CONFIG_NFS_V4_1)
+static int decode_exchange_id(struct xdr_stream *xdr,
+                             struct nfs41_exchange_id_res *res)
+{
+       __be32 *p;
+       uint32_t dummy;
+       int status;
+       struct nfs_client *clp = res->client;
+
+       status = decode_op_hdr(xdr, OP_EXCHANGE_ID);
+       if (status)
+               return status;
+
+       READ_BUF(8);
+       READ64(clp->cl_ex_clid);
+       READ_BUF(12);
+       READ32(clp->cl_seqid);
+       READ32(clp->cl_exchange_flags);
+
+       /* We ask for SP4_NONE */
+       READ32(dummy);
+       if (dummy != SP4_NONE)
+               return -EIO;
+
+       /* Throw away minor_id */
+       READ_BUF(8);
+
+       /* Throw away Major id */
+       READ_BUF(4);
+       READ32(dummy);
+       READ_BUF(dummy);
+
+       /* Throw away server_scope */
+       READ_BUF(4);
+       READ32(dummy);
+       READ_BUF(dummy);
+
+       /* Throw away Implementation id array */
+       READ_BUF(4);
+       READ32(dummy);
+       READ_BUF(dummy);
+
+       return 0;
+}
+#endif /* CONFIG_NFS_V4_1 */
+
 static int decode_sequence(struct xdr_stream *xdr,
                           struct nfs4_sequence_res *res,
                           struct rpc_rqst *rqstp)
        return status;
 }
 
+#if defined(CONFIG_NFS_V4_1)
+/*
+ * EXCHANGE_ID request
+ */
+static int nfs4_xdr_dec_exchange_id(struct rpc_rqst *rqstp, uint32_t *p,
+                                   void *res)
+{
+       struct xdr_stream xdr;
+       struct compound_hdr hdr;
+       int status;
+
+       xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
+       status = decode_compound_hdr(&xdr, &hdr);
+       if (!status)
+               status = decode_exchange_id(&xdr, res);
+       return status;
+}
+#endif /* CONFIG_NFS_V4_1 */
+
 __be32 *nfs4_decode_dirent(__be32 *p, struct nfs_entry *entry, int plus)
 {
        uint32_t bitmap[2] = {0};
   PROC(GETACL,         enc_getacl,     dec_getacl),
   PROC(SETACL,         enc_setacl,     dec_setacl),
   PROC(FS_LOCATIONS,   enc_fs_locations, dec_fs_locations),
+#if defined(CONFIG_NFS_V4_1)
+  PROC(EXCHANGE_ID,    enc_exchange_id,        dec_exchange_id),
+#endif /* CONFIG_NFS_V4_1 */
 };
 
 struct rpc_version             nfs_version4 = {