Merge branch 'parisc-4.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...

[cascardo/linux.git] / fs / nfs / callback_proc.c

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index f0939d0..618ced3 100644 (file)
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -354,47 +354,38 @@ out:
  * a single outstanding callback request at a time.
  */
 static __be32
-validate_seqid(struct nfs4_slot_table *tbl, struct cb_sequenceargs * args)
+validate_seqid(const struct nfs4_slot_table *tbl, const struct nfs4_slot *slot,
+               const struct cb_sequenceargs * args)
 {
-       struct nfs4_slot *slot;
-
-       dprintk("%s enter. slotid %u seqid %u\n",
-               __func__, args->csa_slotid, args->csa_sequenceid);
+       dprintk("%s enter. slotid %u seqid %u, slot table seqid: %u\n",
+               __func__, args->csa_slotid, args->csa_sequenceid, slot->seq_nr);
 
-       if (args->csa_slotid >= NFS41_BC_MAX_CALLBACKS)
+       if (args->csa_slotid > tbl->server_highest_slotid)
                return htonl(NFS4ERR_BADSLOT);
 
-       slot = tbl->slots + args->csa_slotid;
-       dprintk("%s slot table seqid: %u\n", __func__, slot->seq_nr);
-
-       /* Normal */
-       if (likely(args->csa_sequenceid == slot->seq_nr + 1))
-               goto out_ok;
-
        /* Replay */
        if (args->csa_sequenceid == slot->seq_nr) {
                dprintk("%s seqid %u is a replay\n",
                        __func__, args->csa_sequenceid);
+               if (nfs4_test_locked_slot(tbl, slot->slot_nr))
+                       return htonl(NFS4ERR_DELAY);
                /* Signal process_op to set this error on next op */
                if (args->csa_cachethis == 0)
                        return htonl(NFS4ERR_RETRY_UNCACHED_REP);
 
-               /* The ca_maxresponsesize_cached is 0 with no DRC */
-               else if (args->csa_cachethis == 1)
-                       return htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
+               /* Liar! We never allowed you to set csa_cachethis != 0 */
+               return htonl(NFS4ERR_SEQ_FALSE_RETRY);
        }
 
        /* Wraparound */
-       if (args->csa_sequenceid == 1 && (slot->seq_nr + 1) == 0) {
-               slot->seq_nr = 1;
-               goto out_ok;
-       }
+       if (unlikely(slot->seq_nr == 0xFFFFFFFFU)) {
+               if (args->csa_sequenceid == 1)
+                       return htonl(NFS4_OK);
+       } else if (likely(args->csa_sequenceid == slot->seq_nr + 1))
+               return htonl(NFS4_OK);
 
        /* Misordered request */
        return htonl(NFS4ERR_SEQ_MISORDERED);
-out_ok:
-       tbl->highest_used_slotid = args->csa_slotid;
-       return htonl(NFS4_OK);
 }
 
 /*
@@ -473,6 +464,12 @@ __be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
        tbl = &clp->cl_session->bc_slot_table;
        slot = tbl->slots + args->csa_slotid;
 
+       /* Set up res before grabbing the spinlock */
+       memcpy(&res->csr_sessionid, &args->csa_sessionid,
+              sizeof(res->csr_sessionid));
+       res->csr_sequenceid = args->csa_sequenceid;
+       res->csr_slotid = args->csa_slotid;
+
        spin_lock(&tbl->slot_tbl_lock);
        /* state manager is resetting the session */
        if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
@@ -485,18 +482,26 @@ __be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
                goto out_unlock;
        }
 
-       memcpy(&res->csr_sessionid, &args->csa_sessionid,
-              sizeof(res->csr_sessionid));
-       res->csr_sequenceid = args->csa_sequenceid;
-       res->csr_slotid = args->csa_slotid;
-       res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
-       res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
+       status = htonl(NFS4ERR_BADSLOT);
+       slot = nfs4_lookup_slot(tbl, args->csa_slotid);
+       if (IS_ERR(slot))
+               goto out_unlock;
+
+       res->csr_highestslotid = tbl->server_highest_slotid;
+       res->csr_target_highestslotid = tbl->target_highest_slotid;
 
-       status = validate_seqid(tbl, args);
+       status = validate_seqid(tbl, slot, args);
        if (status)
                goto out_unlock;
+       if (!nfs4_try_to_lock_slot(tbl, slot)) {
+               status = htonl(NFS4ERR_DELAY);
+               goto out_unlock;
+       }
+       cps->slot = slot;
 
-       cps->slotid = args->csa_slotid;
+       /* The ca_maxresponsesize_cached is 0 with no DRC */
+       if (args->csa_cachethis != 0)
+               return htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
 
        /*
         * Check for pending referring calls.  If a match is found, a
@@ -513,7 +518,7 @@ __be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
         * If CB_SEQUENCE returns an error, then the state of the slot
         * (sequence ID, cached reply) MUST NOT change.
         */
-       slot->seq_nr++;
+       slot->seq_nr = args->csa_sequenceid;
 out_unlock:
        spin_unlock(&tbl->slot_tbl_lock);