NFSv4.1: nfs4_fl_prepare_ds must be careful about reporting success.
authorNeilBrown <neilb@suse.com>
Mon, 19 Dec 2016 00:19:31 +0000 (11:19 +1100)
committerTrond Myklebust <trond.myklebust@primarydata.com>
Mon, 19 Dec 2016 22:29:48 +0000 (17:29 -0500)
commitcfd278c280f997cf2fe4662e0acab0fe465f637b
tree963bf8eb8afb2d1085ef8aaf09be6524fe70e5c5
parent1c48cee83bc2631ab8533311d594aaafe81d8aa9
NFSv4.1: nfs4_fl_prepare_ds must be careful about reporting success.

Various places assume that if nfs4_fl_prepare_ds() turns a non-NULL 'ds',
then ds->ds_clp will also be non-NULL.

This is not necessasrily true in the case when the process received a fatal signal
while nfs4_pnfs_ds_connect is waiting in nfs4_wait_ds_connect().
In that case ->ds_clp may not be set, and the devid may not recently have been marked
unavailable.

So add a test for ds_clp == NULL and return NULL in that case.

Fixes: c23266d532b4 ("NFS4.1 Fix data server connection race")
Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: Olga Kornievskaia <aglo@umich.edu>
Acked-by: Adamson, Andy <William.Adamson@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
fs/nfs/filelayout/filelayoutdev.c