NFSv4.1: Remove a bogus BUG_ON() in nfs4_layoutreturn_done

Ever since commit 0a57cdac3f (NFSv4.1 send layoutreturn to fence
disconnected data server) we've been sending layoutreturn calls
while there is potentially still outstanding I/O to the data
servers. The reason we do this is to avoid races between replayed
writes to the MDS and the original writes to the DS.

When this happens, the BUG_ON() in nfs4_layoutreturn_done can
be triggered because it assumes that we would never call
layoutreturn without knowing that all I/O to the DS is
finished. The fix is to remove the BUG_ON() now that the
assumptions behind the test are obsolete.

Reported-by: Boaz Harrosh <bharrosh@panasas.com>
Reported-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [>=3.5]
This commit is contained in:
Trond Myklebust 2012-08-08 16:03:13 -04:00
parent 7de6e28417
commit 47fbf7976e

View file

@ -6359,12 +6359,8 @@ static void nfs4_layoutreturn_done(struct rpc_task *task, void *calldata)
return;
}
spin_lock(&lo->plh_inode->i_lock);
if (task->tk_status == 0) {
if (lrp->res.lrs_present) {
pnfs_set_layout_stateid(lo, &lrp->res.stateid, true);
} else
BUG_ON(!list_empty(&lo->plh_segs));
}
if (task->tk_status == 0 && lrp->res.lrs_present)
pnfs_set_layout_stateid(lo, &lrp->res.stateid, true);
lo->plh_block_lgets--;
spin_unlock(&lo->plh_inode->i_lock);
dprintk("<-- %s\n", __func__);