NFS: Add migration recovery callouts in nfs4proc.c

When a server returns NFS4ERR_MOVED, trigger the new migration
recovery logic in the state manager.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 20 insertions, 2 deletions

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index fa87f81527b3..a1f620950f11 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -384,6 +384,11 @@ static int nfs4_handle_exception(struct nfs_server *server, int errorcode, struc
                 case -NFS4ERR_STALE_CLIENTID:
                         nfs4_schedule_lease_recovery(clp);
                         goto wait_on_recovery;
+                case -NFS4ERR_MOVED:
+                        ret = nfs4_schedule_migration_recovery(server);
+                        if (ret < 0)
+                                break;
+                        goto wait_on_recovery;
 #if defined(CONFIG_NFS_V4_1)
                 case -NFS4ERR_BADSESSION:
                 case -NFS4ERR_BADSLOT:
@@ -431,6 +436,8 @@ static int nfs4_handle_exception(struct nfs_server *server, int errorcode, struc
         return nfs4_map_errors(ret);
 wait_on_recovery:
         ret = nfs4_wait_clnt_recover(clp);
+        if (test_bit(NFS_MIG_FAILED, &server->mig_status))
+                return -EIO;
         if (ret == 0)
                 exception->retry = 1;
         return ret;
@@ -2974,11 +2981,16 @@ static int nfs4_get_referral(struct rpc_clnt *client, struct inode *dir,
         status = nfs4_proc_fs_locations(client, dir, name, locations, page);
         if (status != 0)
                 goto out;
-        /* Make sure server returned a different fsid for the referral */
+
+        /*
+         * If the fsid didn't change, this is a migration event, not a
+         * referral.  Cause us to drop into the exception handler, which
+         * will kick off migration recovery.
+         */
         if (nfs_fsid_equal(&NFS_SERVER(dir)->fsid, &locations->fattr.fsid)) {
                 dprintk("%s: server did not return a different fsid for"
                         " a referral at %s\n", __func__, name->name);
-                status = -EIO;
+                status = -NFS4ERR_MOVED;
                 goto out;
         }
         /* Fixup attributes for the nfs_lookup() call to nfs_fhget() */
@@ -4739,6 +4751,10 @@ nfs4_async_handle_error(struct rpc_task *task, const struct nfs_server *server,
                 case -NFS4ERR_STALE_CLIENTID:
                         nfs4_schedule_lease_recovery(clp);
                         goto wait_on_recovery;
+                case -NFS4ERR_MOVED:
+                        if (nfs4_schedule_migration_recovery(server) < 0)
+                                goto recovery_failed;
+                        goto wait_on_recovery;
 #if defined(CONFIG_NFS_V4_1)
                 case -NFS4ERR_BADSESSION:
                 case -NFS4ERR_BADSLOT:
@@ -4769,6 +4785,8 @@ wait_on_recovery:
         rpc_sleep_on(&clp->cl_rpcwaitq, task, NULL);
         if (test_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) == 0)
                 rpc_wake_up_queued_task(&clp->cl_rpcwaitq, task);
+        if (test_bit(NFS_MIG_FAILED, &server->mig_status))
+                goto recovery_failed;
 restart_call:
         task->tk_status = 0;
         return -EAGAIN;