diff options
Diffstat (limited to 'net/sched/act_api.c')
-rw-r--r-- | net/sched/act_api.c | 92 |
1 files changed, 72 insertions, 20 deletions
diff --git a/net/sched/act_api.c b/net/sched/act_api.c index eefe8c2fe667..9511502e1cbb 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -303,7 +303,9 @@ static bool __tcf_idr_check(struct tc_action_net *tn, u32 index, spin_lock(&idrinfo->lock); p = idr_find(&idrinfo->action_idr, index); - if (p) { + if (IS_ERR(p)) { + p = NULL; + } else if (p) { refcount_inc(&p->tcfa_refcnt); if (bind) atomic_inc(&p->tcfa_bindcnt); @@ -371,7 +373,6 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est, { struct tc_action *p = kzalloc(ops->size, GFP_KERNEL); struct tcf_idrinfo *idrinfo = tn->idrinfo; - struct idr *idr = &idrinfo->action_idr; int err = -ENOMEM; if (unlikely(!p)) @@ -389,20 +390,6 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est, goto err2; } spin_lock_init(&p->tcfa_lock); - idr_preload(GFP_KERNEL); - spin_lock(&idrinfo->lock); - /* user doesn't specify an index */ - if (!index) { - index = 1; - err = idr_alloc_u32(idr, NULL, &index, UINT_MAX, GFP_ATOMIC); - } else { - err = idr_alloc_u32(idr, NULL, &index, index, GFP_ATOMIC); - } - spin_unlock(&idrinfo->lock); - idr_preload_end(); - if (err) - goto err3; - p->tcfa_index = index; p->tcfa_tm.install = jiffies; p->tcfa_tm.lastuse = jiffies; @@ -412,7 +399,7 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est, &p->tcfa_rate_est, &p->tcfa_lock, NULL, est); if (err) - goto err4; + goto err3; } p->idrinfo = idrinfo; @@ -420,8 +407,6 @@ 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: @@ -437,11 +422,78 @@ void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a) struct tcf_idrinfo *idrinfo = tn->idrinfo; spin_lock(&idrinfo->lock); - idr_replace(&idrinfo->action_idr, a, a->tcfa_index); + /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */ + WARN_ON(!IS_ERR(idr_replace(&idrinfo->action_idr, a, a->tcfa_index))); spin_unlock(&idrinfo->lock); } EXPORT_SYMBOL(tcf_idr_insert); +/* Cleanup idr index that was allocated but not initialized. */ + +void tcf_idr_cleanup(struct tc_action_net *tn, u32 index) +{ + struct tcf_idrinfo *idrinfo = tn->idrinfo; + + spin_lock(&idrinfo->lock); + /* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */ + WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index))); + spin_unlock(&idrinfo->lock); +} +EXPORT_SYMBOL(tcf_idr_cleanup); + +/* Check if action with specified index exists. If actions is found, increments + * its reference and bind counters, and return 1. Otherwise insert temporary + * error pointer (to prevent concurrent users from inserting actions with same + * index) and return 0. + */ + +int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index, + struct tc_action **a, int bind) +{ + struct tcf_idrinfo *idrinfo = tn->idrinfo; + struct tc_action *p; + int ret; + +again: + spin_lock(&idrinfo->lock); + if (*index) { + p = idr_find(&idrinfo->action_idr, *index); + if (IS_ERR(p)) { + /* This means that another process allocated + * index but did not assign the pointer yet. + */ + spin_unlock(&idrinfo->lock); + goto again; + } + + if (p) { + refcount_inc(&p->tcfa_refcnt); + if (bind) + atomic_inc(&p->tcfa_bindcnt); + *a = p; + ret = 1; + } else { + *a = NULL; + ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index, + *index, GFP_ATOMIC); + if (!ret) + idr_replace(&idrinfo->action_idr, + ERR_PTR(-EBUSY), *index); + } + } else { + *index = 1; + *a = NULL; + ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index, + UINT_MAX, GFP_ATOMIC); + if (!ret) + idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY), + *index); + } + spin_unlock(&idrinfo->lock); + return ret; +} +EXPORT_SYMBOL(tcf_idr_check_alloc); + void tcf_idrinfo_destroy(const struct tc_action_ops *ops, struct tcf_idrinfo *idrinfo) { |