[PATCH v2 09/17] net sched actions: Convert to use idr_alloc_u32

[Matthew Wilcox]

From: Matthew Wilcox <mawil...@microsoft.com>

Use the new helper.  Also untangle the error path, and in so doing
noticed that estimator generator failure would lead to us leaking an
ID.  Fix that bug.

Signed-off-by: Matthew Wilcox <mawil...@microsoft.com>
---
 net/sched/act_api.c | 60 ++++++++++++++++++++++-------------------------------
 1 file changed, 25 insertions(+), 35 deletions(-)

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index efb90b8a3bf0..156302c110af 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -274,7 +274,6 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, 
struct nlattr *est,
        struct tcf_idrinfo *idrinfo = tn->idrinfo;
        struct idr *idr = &idrinfo->action_idr;
        int err = -ENOMEM;
-       unsigned long idr_index;
 
        if (unlikely(!p))
                return -ENOMEM;
@@ -284,45 +283,28 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, 
struct nlattr *est,
 
        if (cpustats) {
                p->cpu_bstats = netdev_alloc_pcpu_stats(struct 
gnet_stats_basic_cpu);
-               if (!p->cpu_bstats) {
-err1:
-                       kfree(p);
-                       return err;
-               }
-               p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
-               if (!p->cpu_qstats) {
-err2:
-                       free_percpu(p->cpu_bstats);
+               if (!p->cpu_bstats)
                        goto err1;
-               }
+               p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
+               if (!p->cpu_qstats)
+                       goto err2;
        }
        spin_lock_init(&p->tcfa_lock);
+       idr_preload(GFP_KERNEL);
+       spin_lock_bh(&idrinfo->lock);
        /* user doesn't specify an index */
        if (!index) {
-               idr_preload(GFP_KERNEL);
-               spin_lock_bh(&idrinfo->lock);
-               err = idr_alloc_ext(idr, NULL, &idr_index, 1, 0,
-                                   GFP_ATOMIC);
-               spin_unlock_bh(&idrinfo->lock);
-               idr_preload_end();
-               if (err) {
-err3:
-                       free_percpu(p->cpu_qstats);
-                       goto err2;
-               }
-               p->tcfa_index = idr_index;
+               index = 1;
+               err = idr_alloc_u32(idr, NULL, &index, UINT_MAX, GFP_ATOMIC);
        } else {
-               idr_preload(GFP_KERNEL);
-               spin_lock_bh(&idrinfo->lock);
-               err = idr_alloc_ext(idr, NULL, NULL, index, index + 1,
-                                   GFP_ATOMIC);
-               spin_unlock_bh(&idrinfo->lock);
-               idr_preload_end();
-               if (err)
-                       goto err3;
-               p->tcfa_index = index;
+               err = idr_alloc_u32(idr, NULL, &index, index, GFP_ATOMIC);
        }
+       spin_unlock_bh(&idrinfo->lock);
+       idr_preload_end();
+       if (err)
+               goto err3;
 
+       p->tcfa_index = index;
        p->tcfa_tm.install = jiffies;
        p->tcfa_tm.lastuse = jiffies;
        p->tcfa_tm.firstuse = 0;
@@ -330,9 +312,8 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, 
struct nlattr *est,
                err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
                                        &p->tcfa_rate_est,
                                        &p->tcfa_lock, NULL, est);
-               if (err) {
-                       goto err3;
-               }
+               if (err)
+                       goto err4;
        }
 
        p->idrinfo = idrinfo;
@@ -340,6 +321,15 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, 
struct nlattr *est,
        INIT_LIST_HEAD(&p->list);
        *a = p;
        return 0;
+err4:
+       idr_remove(idr, index);
+err3:
+       free_percpu(p->cpu_qstats);
+err2:
+       free_percpu(p->cpu_bstats);
+err1:
+       kfree(p);
+       return err;
 }
 EXPORT_SYMBOL(tcf_idr_create);
 
-- 
2.15.0