SUNRPC: remove non-exclusive pipe creation from RPC pipefs

This patch-set was created in context of clone of git branch:
git://git.linux-nfs.org/projects/trondmy/nfs-2.6.git.

v2:
1) Rebased of current repo state (i.e. all commits were pulled before apply)

I feel it is ready for inclusion if no objections will appear.

SUNRPC pipefs non-exclusive pipe creation code looks obsolete. IOW, as I see
it, all pipes are creating with unique full path and only once.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 6 insertions, 38 deletions

diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 63a7a7add21e..8e3397fc0a7d 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -554,7 +554,6 @@ static int __rpc_mkpipe(struct inode *dir, struct dentry *dentry,
         if (err)
                 return err;
         rpci = RPC_I(dentry->d_inode);
-        rpci->nkern_readwriters = 1;
         rpci->private = private;
         rpci->flags = flags;
         rpci->ops = ops;
@@ -587,16 +586,12 @@ static int __rpc_unlink(struct inode *dir, struct dentry *dentry)
 static int __rpc_rmpipe(struct inode *dir, struct dentry *dentry)
 {
         struct inode *inode = dentry->d_inode;
-        struct rpc_inode *rpci = RPC_I(inode);
 
-        rpci->nkern_readwriters--;
-        if (rpci->nkern_readwriters != 0)
-                return 0;
         rpc_close_pipes(inode);
         return __rpc_unlink(dir, dentry);
 }
 
-static struct dentry *__rpc_lookup_create(struct dentry *parent,
+static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent,
                                           struct qstr *name)
 {
         struct dentry *dentry;
@@ -604,27 +599,13 @@ static struct dentry *__rpc_lookup_create(struct dentry *parent,
         dentry = d_lookup(parent, name);
         if (!dentry) {
                 dentry = d_alloc(parent, name);
-                if (!dentry) {
-                        dentry = ERR_PTR(-ENOMEM);
-                        goto out_err;
-                }
+                if (!dentry)
+                        return ERR_PTR(-ENOMEM);
         }
-        if (!dentry->d_inode)
+        if (dentry->d_inode == NULL) {
                 d_set_d_op(dentry, &rpc_dentry_operations);
-out_err:
-        return dentry;
-}
-
-static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent,
-                                          struct qstr *name)
-{
-        struct dentry *dentry;
-
-        dentry = __rpc_lookup_create(parent, name);
-        if (IS_ERR(dentry))
-                return dentry;
-        if (dentry->d_inode == NULL)
                 return dentry;
+        }
         dput(dentry);
         return ERR_PTR(-EEXIST);
 }
@@ -812,22 +793,9 @@ struct dentry *rpc_mkpipe(struct dentry *parent, const char *name,
         q.hash = full_name_hash(q.name, q.len),
 
         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
-        dentry = __rpc_lookup_create(parent, &q);
+        dentry = __rpc_lookup_create_exclusive(parent, &q);
         if (IS_ERR(dentry))
                 goto out;
-        if (dentry->d_inode) {
-                struct rpc_inode *rpci = RPC_I(dentry->d_inode);
-                if (rpci->private != private ||
-                                rpci->ops != ops ||
-                                rpci->flags != flags) {
-                        dput (dentry);
-                        err = -EBUSY;
-                        goto out_err;
-                }
-                rpci->nkern_readwriters++;
-                goto out;
-        }
-
         err = __rpc_mkpipe(dir, dentry, umode, &rpc_pipe_fops,
                            private, ops, flags);
         if (err)