Merge tag 'v3.12' into core/locking to pick up mutex upates

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 11 insertions, 9 deletions

diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c
index 95604f64cab..c7c295e556e 100644
--- a/fs/nfs/nfs4filelayoutdev.c
+++ b/fs/nfs/nfs4filelayoutdev.c
@@ -185,6 +185,7 @@ nfs4_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds)
 	if (status)
 		goto out_put;
 
+	smp_wmb();
 	ds->ds_clp = clp;
 	dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
 out:
@@ -801,34 +802,35 @@ nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
 	struct nfs4_file_layout_dsaddr *dsaddr = FILELAYOUT_LSEG(lseg)->dsaddr;
 	struct nfs4_pnfs_ds *ds = dsaddr->ds_list[ds_idx];
 	struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
-
-	if (filelayout_test_devid_unavailable(devid))
-		return NULL;
+	struct nfs4_pnfs_ds *ret = ds;
 
 	if (ds == NULL) {
 		printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
 			__func__, ds_idx);
 		filelayout_mark_devid_invalid(devid);
-		return NULL;
+		goto out;
 	}
+	smp_rmb();
 	if (ds->ds_clp)
-		return ds;
+		goto out_test_devid;
 
 	if (test_and_set_bit(NFS4DS_CONNECTING, &ds->ds_state) == 0) {
 		struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
 		int err;
 
 		err = nfs4_ds_connect(s, ds);
-		if (err) {
+		if (err)
 			nfs4_mark_deviceid_unavailable(devid);
-			ds = NULL;
-		}
 		nfs4_clear_ds_conn_bit(ds);
 	} else {
 		/* Either ds is connected, or ds is NULL */
 		nfs4_wait_ds_connect(ds);
 	}
-	return ds;
+out_test_devid:
+	if (filelayout_test_devid_unavailable(devid))
+		ret = NULL;
+out:
+	return ret;
 }
 
 module_param(dataserver_retrans, uint, 0644);