From 52b26a3e1bb3e065c32b3febdac1e1f117d88e15 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 26 Sep 2013 14:08:36 -0400 Subject: NFSv4.1: nfs4_fl_prepare_ds - fix bugs when the connect attempt fails - Fix an Oops when nfs4_ds_connect() returns an error. - Always check the device status after waiting for a connect to complete. Reported-by: Andy Adamson Reported-by: Jeff Layton Signed-off-by: Trond Myklebust Cc: # v3.10+ --- fs/nfs/nfs4filelayoutdev.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) (limited to 'fs/nfs/nfs4filelayoutdev.c') diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c index 95604f64cab..cd3aef571c3 100644 --- a/fs/nfs/nfs4filelayoutdev.c +++ b/fs/nfs/nfs4filelayoutdev.c @@ -801,34 +801,34 @@ 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; } 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); -- cgit v1.2.3-70-g09d2 From acd65e5bc1986d0089efec3fe63e52ea0c406d6d Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 26 Sep 2013 14:32:56 -0400 Subject: NFSv4.1: Ensure memory ordering between nfs4_ds_connect and nfs4_fl_prepare_ds We need to ensure that the initialisation of the data server nfs_client structure in nfs4_ds_connect is correctly ordered w.r.t. the read of ds->ds_clp in nfs4_fl_prepare_ds. Signed-off-by: Trond Myklebust --- fs/nfs/nfs4filelayoutdev.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/nfs/nfs4filelayoutdev.c') diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c index cd3aef571c3..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: @@ -809,6 +810,7 @@ nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx) filelayout_mark_devid_invalid(devid); goto out; } + smp_rmb(); if (ds->ds_clp) goto out_test_devid; -- cgit v1.2.3-70-g09d2