Return the delegation when deleting sillyrenamed files

Add a callback to return the delegation in order to allow generic NFS
code to return the delegation when appropriate.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs/nfs/nfs3proc.c

@@ -984,6 +984,13 @@ static int nfs3_have_delegation(struct inode *inode, fmode_t type, int flags)
 	return 0;
 }
 
+static int nfs3_return_delegation(struct inode *inode)
+{
+	if (S_ISREG(inode->i_mode))
+		nfs_wb_all(inode);
+	return 0;
+}
+
 static const struct inode_operations nfs3_dir_inode_operations = {
 	.create		= nfs_create,
 	.atomic_open	= nfs_atomic_open_v23,
@@ -1062,6 +1069,7 @@ const struct nfs_rpc_ops nfs_v3_clientops = {
 	.clear_acl_cache = forget_all_cached_acls,
 	.close_context	= nfs_close_context,
 	.have_delegation = nfs3_have_delegation,
+	.return_delegation = nfs3_return_delegation,
 	.alloc_client	= nfs_alloc_client,
 	.init_client	= nfs_init_client,
 	.free_client	= nfs_free_client,

fs/nfs/nfs4proc.c

@@ -10871,6 +10871,7 @@ const struct nfs_rpc_ops nfs_v4_clientops = {
 	.close_context  = nfs4_close_context,
 	.open_context	= nfs4_atomic_open,
 	.have_delegation = nfs4_have_delegation,
+	.return_delegation = nfs4_inode_return_delegation,
 	.alloc_client	= nfs4_alloc_client,
 	.init_client	= nfs4_init_client,
 	.free_client	= nfs4_free_client,

fs/nfs/proc.c

@@ -692,6 +692,13 @@ static int nfs_have_delegation(struct inode *inode, fmode_t type, int flags)
 	return 0;
 }
 
+static int nfs_return_delegation(struct inode *inode)
+{
+	if (S_ISREG(inode->i_mode))
+		nfs_wb_all(inode);
+	return 0;
+}
+
 static const struct inode_operations nfs_dir_inode_operations = {
 	.create		= nfs_create,
 	.lookup		= nfs_lookup,
@@ -757,6 +764,7 @@ const struct nfs_rpc_ops nfs_v2_clientops = {
 	.lock_check_bounds = nfs_lock_check_bounds,
 	.close_context	= nfs_close_context,
 	.have_delegation = nfs_have_delegation,
+	.return_delegation = nfs_return_delegation,
 	.alloc_client	= nfs_alloc_client,
 	.init_client	= nfs_init_client,
 	.free_client	= nfs_free_client,

fs/nfs/unlink.c

@@ -232,6 +232,8 @@ nfs_complete_unlink(struct dentry *dentry, struct inode *inode)
 	dentry->d_fsdata = NULL;
 	spin_unlock(&dentry->d_lock);
 
+	NFS_PROTO(inode)->return_delegation(inode);
+
 	if (NFS_STALE(inode) || !nfs_call_unlink(dentry, inode, data))
 		nfs_free_unlinkdata(data);
 }

include/linux/nfs_xdr.h

@@ -1840,6 +1840,7 @@ struct nfs_rpc_ops {
 				struct iattr *iattr,
 				int *);
 	int (*have_delegation)(struct inode *, fmode_t, int);
+	int (*return_delegation)(struct inode *);
 	struct nfs_client *(*alloc_client) (const struct nfs_client_initdata *);
 	struct nfs_client *(*init_client) (struct nfs_client *,
 				const struct nfs_client_initdata *);