From 8dcbec6d20eb881ba368d0aebc3a8a678aebb1da Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 8 Jun 2017 11:52:44 -0400 Subject: NFSv4.1: Handle EXCHGID4_FLAG_CONFIRMED_R during NFSv4.1 migration Transparent State Migration copies a client's lease state from the server where a filesystem used to reside to the server where it now resides. When an NFSv4.1 client first contacts that destination server, it uses EXCHANGE_ID to detect trunking relationships. The lease that was copied there is returned to that client, but the destination server sets EXCHGID4_FLAG_CONFIRMED_R when replying to the client. This is because the lease was confirmed on the source server (before it was copied). Normally, when CONFIRMED_R is set, a client purges the lease and creates a new one. However, that throws away the entire benefit of Transparent State Migration. Therefore, the client must not purge that lease when it is possible that Transparent State Migration has occurred. Reported-by: Xuan Qi Signed-off-by: Chuck Lever Tested-by: Xuan Qi Signed-off-by: Anna Schumaker --- fs/nfs/nfs4state.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) (limited to 'fs/nfs/nfs4state.c') diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index b34de036501b..83f8e60bb1e3 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -352,11 +352,17 @@ int nfs41_discover_server_trunking(struct nfs_client *clp, if (clp != *result) return 0; - /* Purge state if the client id was established in a prior instance */ - if (clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R) - set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state); - else - set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); + /* + * Purge state if the client id was established in a prior + * instance and the client id could not have arrived on the + * server via Transparent State Migration. + */ + if (clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R) { + if (!test_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags)) + set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state); + else + set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state); + } nfs4_schedule_state_manager(clp); status = nfs_wait_client_init_complete(clp); if (status < 0) -- cgit v1.2.3