Merge tag 'nfs-for-3.11-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull second set of NFS client updates from Trond Myklebust:
 "This mainly contains some small readdir optimisations that had
  dependencies on Al Viro's readdir rewrite.  There is also a fix for a
  nasty deadlock which surfaced earlier in this merge window.

  Highlights include:
   - Fix an_rpc pipefs regression that causes a deadlock on mount
   - Readdir optimisations by Scott Mayhew and Jeff Layton
   - clean up the rpc_pipefs dentry operation setup"

* tag 'nfs-for-3.11-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: Fix a deadlock in rpc_client_register()
  rpc_pipe: rpc_dir_inode_operations can be static
  NFS: Allow nfs_updatepage to extend a write under additional circumstances
  NFS: Make nfs_readdir revalidate less often
  NFS: Make nfs_attribute_cache_expired() non-static
  rpc_pipe: set dentry operations at d_alloc time
  nfs: set verifier on existing dentries in nfs_prime_dcache

2 files changed, 29 insertions, 12 deletions

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index f0339ae9bf37..aa401560777b 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -290,7 +290,7 @@ static int rpc_client_register(const struct rpc_create_args *args,
         struct rpc_auth *auth;
         struct net *net = rpc_net_ns(clnt);
         struct super_block *pipefs_sb;
-        int err = 0;
+        int err;
 
         pipefs_sb = rpc_get_sb_net(net);
         if (pipefs_sb) {
@@ -299,6 +299,10 @@ static int rpc_client_register(const struct rpc_create_args *args,
                         goto out;
         }
 
+        rpc_register_client(clnt);
+        if (pipefs_sb)
+                rpc_put_sb_net(net);
+
         auth = rpcauth_create(args->authflavor, clnt);
         if (IS_ERR(auth)) {
                 dprintk("RPC:       Couldn't create auth handle (flavor %u)\n",
@@ -306,16 +310,14 @@ static int rpc_client_register(const struct rpc_create_args *args,
                 err = PTR_ERR(auth);
                 goto err_auth;
         }
-
-        rpc_register_client(clnt);
+        return 0;
+err_auth:
+        pipefs_sb = rpc_get_sb_net(net);
+        __rpc_clnt_remove_pipedir(clnt);
 out:
         if (pipefs_sb)
                 rpc_put_sb_net(net);
         return err;
-
-err_auth:
-        __rpc_clnt_remove_pipedir(clnt);
-        goto out;
 }
 
 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt)
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 4679df5a6d50..61239a2cb786 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -480,6 +480,23 @@ static const struct dentry_operations rpc_dentry_operations = {
         .d_delete = rpc_delete_dentry,
 };
 
+/*
+ * Lookup the data. This is trivial - if the dentry didn't already
+ * exist, we know it is negative.
+ */
+static struct dentry *
+rpc_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
+{
+        if (dentry->d_name.len > NAME_MAX)
+                return ERR_PTR(-ENAMETOOLONG);
+        d_add(dentry, NULL);
+        return NULL;
+}
+
+static const struct inode_operations rpc_dir_inode_operations = {
+        .lookup         = rpc_lookup,
+};
+
 static struct inode *
 rpc_get_inode(struct super_block *sb, umode_t mode)
 {
@@ -492,7 +509,7 @@ rpc_get_inode(struct super_block *sb, umode_t mode)
         switch (mode & S_IFMT) {
         case S_IFDIR:
                 inode->i_fop = &simple_dir_operations;
-                inode->i_op = &simple_dir_inode_operations;
+                inode->i_op = &rpc_dir_inode_operations;
                 inc_nlink(inode);
         default:
                 break;
@@ -666,11 +683,8 @@ static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent,
                 if (!dentry)
                         return ERR_PTR(-ENOMEM);
         }
-        if (dentry->d_inode == NULL) {
-                if (!dentry->d_op)
-                        d_set_d_op(dentry, &rpc_dentry_operations);
+        if (dentry->d_inode == NULL)
                 return dentry;
-        }
         dput(dentry);
         return ERR_PTR(-EEXIST);
 }
@@ -1117,6 +1131,7 @@ rpc_fill_super(struct super_block *sb, void *data, int silent)
         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
         sb->s_magic = RPCAUTH_GSSMAGIC;
         sb->s_op = &s_ops;
+        sb->s_d_op = &rpc_dentry_operations;
         sb->s_time_gran = 1;
 
         inode = rpc_get_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);