NFS/pnfs: Fix dereference of layout cred in pnfs_layoutcommit_inode()

Ensure that the dereference of the layout cred is atomic with the
stateid.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 6fcf26b168163304367f1478c3b30b661e029646..84029c9b2b1bbe8788cb0ca91b36d05b789bf6b7 100644 (file)
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -3137,10 +3137,10 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
        end_pos = nfsi->layout->plh_lwb;
 
        nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
+       data->cred = get_cred(nfsi->layout->plh_lc_cred);
        spin_unlock(&inode->i_lock);
 
        data->args.inode = inode;
-       data->cred = get_cred(nfsi->layout->plh_lc_cred);
        nfs_fattr_init(&data->fattr);
        data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
        data->res.fattr = &data->fattr;