From 30e8df149e331f8ca1d9d104c079ad678cd63f77 Mon Sep 17 00:00:00 2001
From: Casey Bodley <cbodley@citi.umich.edu>
Date: Thu, 10 May 2012 12:26:32 -0400
Subject: [PATCH] session: handle NFS4ERR_BADSLOT errors

NFS4ERR_BADSLOT indicates that the supplied slotid is outside the server's expected range.  update table.max_slots to this value to prevent it from being used again, then acquire a new slot and retry the rpc

Signed-off-by: Casey Bodley <cbodley@citi.umich.edu>
---
 daemon/nfs41.h          |  4 ++++
 daemon/nfs41_compound.c |  6 ++++++
 daemon/nfs41_session.c  | 27 +++++++++++++++++++++++++++
 3 files changed, 37 insertions(+)

diff --git a/daemon/nfs41.h b/daemon/nfs41.h
index b09fdb0..2881e66 100644
--- a/daemon/nfs41.h
+++ b/daemon/nfs41.h
@@ -370,6 +370,10 @@ void nfs41_session_sequence(
     nfs41_session *session,
     bool_t cachethis);
 
+int nfs41_session_bad_slot(
+    IN nfs41_session *session,
+    IN OUT struct __nfs41_sequence_args *args);
+
 
 /* nfs41_server.c */
 void nfs41_server_list_init();
diff --git a/daemon/nfs41_compound.c b/daemon/nfs41_compound.c
index 5d7fcfd..f7e3d65 100644
--- a/daemon/nfs41_compound.c
+++ b/daemon/nfs41_compound.c
@@ -254,6 +254,12 @@ retry:
             goto do_retry;
         goto out;
 
+    case NFS4ERR_BADSLOT:
+        /* free the slot and retry with a new one */
+        if (op1 != OP_SEQUENCE || nfs41_session_bad_slot(session, args))
+            goto out;
+        goto retry;
+
     case NFS4ERR_GRACE:
     case NFS4ERR_DELAY:
 #define RETRY_INDEFINITELY
diff --git a/daemon/nfs41_session.c b/daemon/nfs41_session.c
index ba93d3d..e67dacc 100644
--- a/daemon/nfs41_session.c
+++ b/daemon/nfs41_session.c
@@ -172,6 +172,33 @@ int nfs41_session_recall_slot(
     return NFS4_OK;
 }
 
+int nfs41_session_bad_slot(
+    IN nfs41_session *session,
+    IN OUT nfs41_sequence_args *args)
+{
+    nfs41_slot_table *table = &session->table;
+    int status = NFS4ERR_BADSLOT;
+
+    if (args->sa_slotid == 0) {
+        eprintf("server bug detected: NFS4ERR_BADSLOT for slotid=0\n");
+        goto out;
+    }
+
+    /* avoid using any slots >= bad_slotid */
+    EnterCriticalSection(&table->lock);
+    if (table->max_slots > args->sa_slotid)
+        resize_slot_table(table, args->sa_slotid);
+    LeaveCriticalSection(&table->lock);
+
+    /* get a new slot */
+    nfs41_session_free_slot(session, args->sa_slotid);
+    nfs41_session_get_slot(session, &args->sa_slotid,
+        &args->sa_sequenceid, &args->sa_highest_slotid);
+    status = NFS4_OK;
+out:
+    return status;
+}
+
 void nfs41_session_sequence(
     nfs41_sequence_args *args,
     nfs41_session *session,