NFSv4.x: Don't return NFS4ERR_NOMATCHING_LAYOUT if we're unmounting

[ Upstream commit 8926cc8302819be9e67f70409ed001ecb2c924a9 ]

If the NFS super block is being unmounted, then we currently may end up
telling the server that we've forgotten the layout while it is actually
still in use by the client.
In that case, just assume that the client will soon return the layout
anyway, and so return NFS4ERR_DELAY in response to the layout recall.

Fixes: 58ac3e59235f ("NFSv4/pnfs: Clean up nfs_layout_find_inode()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index f7786e00a6a7f16037c96c35fd47a3a19d84d8b0..ed9d580826f5a6390e504fab194f8bd67843306f 100644 (file)
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -137,12 +137,12 @@ static struct inode *nfs_layout_find_inode_by_stateid(struct nfs_client *clp,
                list_for_each_entry_rcu(lo, &server->layouts, plh_layouts) {
                        if (!pnfs_layout_is_valid(lo))
                                continue;
-                       if (stateid != NULL &&
-                           !nfs4_stateid_match_other(stateid, &lo->plh_stateid))
+                       if (!nfs4_stateid_match_other(stateid, &lo->plh_stateid))
                                continue;
-                       if (!nfs_sb_active(server->super))
-                               continue;
-                       inode = igrab(lo->plh_inode);
+                       if (nfs_sb_active(server->super))
+                               inode = igrab(lo->plh_inode);
+                       else
+                               inode = ERR_PTR(-EAGAIN);
                        rcu_read_unlock();
                        if (inode)
                                return inode;
@@ -176,9 +176,10 @@ static struct inode *nfs_layout_find_inode_by_fh(struct nfs_client *clp,
                                continue;
                        if (nfsi->layout != lo)
                                continue;
-                       if (!nfs_sb_active(server->super))
-                               continue;
-                       inode = igrab(lo->plh_inode);
+                       if (nfs_sb_active(server->super))
+                               inode = igrab(lo->plh_inode);
+                       else
+                               inode = ERR_PTR(-EAGAIN);
                        rcu_read_unlock();
                        if (inode)
                                return inode;