[patch net-next] net/sched: let chain_get to figure out the return value

[Jiri Pirko]

From: Jiri Pirko <j...@mellanox.com>

Alhough I believe that this create/nocreate dance is completelly
pointless, at least make it a bit nicer and easier to read.
Push the decision on what error value is returned to chain_get function
and use ERR macros.

Signed-off-by: Jiri Pirko <j...@mellanox.com>
---
 net/sched/act_api.c |  4 ++--
 net/sched/cls_api.c | 15 ++++++---------
 2 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index aed6cf2..42bb75a 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -35,8 +35,8 @@ static int tcf_action_goto_chain_init(struct tc_action *a, 
struct tcf_proto *tp)
        if (!tp)
                return -EINVAL;
        a->goto_chain = tcf_chain_get(tp->chain->block, chain_index, true);
-       if (!a->goto_chain)
-               return -ENOMEM;
+       if (IS_ERR(a->goto_chain))
+               return PTR_ERR(a->goto_chain);
        return 0;
 }
 
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 39da0c5..deec814 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -193,7 +193,7 @@ static struct tcf_chain *tcf_chain_create(struct tcf_block 
*block,
 
        chain = kzalloc(sizeof(*chain), GFP_KERNEL);
        if (!chain)
-               return NULL;
+               return ERR_PTR(-ENOMEM);
        list_add_tail(&chain->list, &block->chain_list);
        chain->block = block;
        chain->index = chain_index;
@@ -231,10 +231,7 @@ struct tcf_chain *tcf_chain_get(struct tcf_block *block, 
u32 chain_index,
                        return chain;
                }
        }
-       if (create)
-               return tcf_chain_create(block, chain_index);
-       else
-               return NULL;
+       return create ? tcf_chain_create(block, chain_index) : ERR_PTR(-EINVAL);
 }
 EXPORT_SYMBOL(tcf_chain_get);
 
@@ -267,8 +264,8 @@ int tcf_block_get(struct tcf_block **p_block,
        INIT_LIST_HEAD(&block->chain_list);
        /* Create chain 0 by default, it has to be always present. */
        chain = tcf_chain_create(block, 0);
-       if (!chain) {
-               err = -ENOMEM;
+       if (IS_ERR(chain)) {
+               err = PTR_ERR(chain);
                goto err_chain_create;
        }
        tcf_chain_filter_chain_ptr_set(chain, p_filter_chain);
@@ -517,8 +514,8 @@ static int tc_ctl_tfilter(struct sk_buff *skb, struct 
nlmsghdr *n,
        }
        chain = tcf_chain_get(block, chain_index,
                              n->nlmsg_type == RTM_NEWTFILTER);
-       if (!chain) {
-               err = n->nlmsg_type == RTM_NEWTFILTER ? -ENOMEM : -EINVAL;
+       if (IS_ERR(chain)) {
+               err = PTR_ERR(chain);
                goto errout;
        }
 
-- 
2.9.3