diff options
| -rw-r--r-- | net/sched/cls_tcindex.c | 44 |
1 files changed, 38 insertions, 6 deletions
diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c index 9904299424a1..065345832a69 100644 --- a/net/sched/cls_tcindex.c +++ b/net/sched/cls_tcindex.c @@ -11,6 +11,7 @@ #include <linux/skbuff.h> #include <linux/errno.h> #include <linux/slab.h> +#include <linux/refcount.h> #include <net/act_api.h> #include <net/netlink.h> #include <net/pkt_cls.h> @@ -26,9 +27,12 @@ #define DEFAULT_HASH_SIZE 64 /* optimized for diffserv */ +struct tcindex_data; + struct tcindex_filter_result { struct tcf_exts exts; struct tcf_result res; + struct tcindex_data *p; struct rcu_work rwork; }; @@ -49,6 +53,7 @@ struct tcindex_data { u32 hash; /* hash table size; 0 if undefined */ u32 alloc_hash; /* allocated size */ u32 fall_through; /* 0: only classify if explicit match */ + refcount_t refcnt; /* a temporary refcnt for perfect hash */ struct rcu_work rwork; }; @@ -57,6 +62,20 @@ static inline int tcindex_filter_is_set(struct tcindex_filter_result *r) return tcf_exts_has_actions(&r->exts) || r->res.classid; } +static void tcindex_data_get(struct tcindex_data *p) +{ + refcount_inc(&p->refcnt); +} + +static void tcindex_data_put(struct tcindex_data *p) +{ + if (refcount_dec_and_test(&p->refcnt)) { + kfree(p->perfect); + kfree(p->h); + kfree(p); + } +} + static struct tcindex_filter_result *tcindex_lookup(struct tcindex_data *p, u16 key) { @@ -141,6 +160,7 @@ static void __tcindex_destroy_rexts(struct tcindex_filter_result *r) { tcf_exts_destroy(&r->exts); tcf_exts_put_net(&r->exts); + tcindex_data_put(r->p); } static void tcindex_destroy_rexts_work(struct work_struct *work) @@ -212,6 +232,8 @@ found: else __tcindex_destroy_fexts(f); } else { + tcindex_data_get(p); + if (tcf_exts_get_net(&r->exts)) tcf_queue_work(&r->rwork, tcindex_destroy_rexts_work); else @@ -228,9 +250,7 @@ static void tcindex_destroy_work(struct work_struct *work) struct tcindex_data, rwork); - kfree(p->perfect); - kfree(p->h); - kfree(p); + tcindex_data_put(p); } static inline int @@ -248,9 +268,11 @@ static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = { }; static int tcindex_filter_result_init(struct tcindex_filter_result *r, + struct tcindex_data *p, struct net *net) { memset(r, 0, sizeof(*r)); + r->p = p; return tcf_exts_init(&r->exts, net, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE); } @@ -290,6 +312,7 @@ static int tcindex_alloc_perfect_hash(struct net *net, struct tcindex_data *cp) TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE); if (err < 0) goto errout; + cp->perfect[i].p = cp; } return 0; @@ -334,6 +357,7 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base, cp->alloc_hash = p->alloc_hash; cp->fall_through = p->fall_through; cp->tp = tp; + refcount_set(&cp->refcnt, 1); /* Paired with tcindex_destroy_work() */ if (tb[TCA_TCINDEX_HASH]) cp->hash = nla_get_u32(tb[TCA_TCINDEX_HASH]); @@ -366,7 +390,7 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base, } cp->h = p->h; - err = tcindex_filter_result_init(&new_filter_result, net); + err = tcindex_filter_result_init(&new_filter_result, cp, net); if (err < 0) goto errout_alloc; if (old_r) @@ -434,7 +458,7 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base, goto errout_alloc; f->key = handle; f->next = NULL; - err = tcindex_filter_result_init(&f->result, net); + err = tcindex_filter_result_init(&f->result, cp, net); if (err < 0) { kfree(f); goto errout_alloc; @@ -447,7 +471,7 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base, } if (old_r && old_r != r) { - err = tcindex_filter_result_init(old_r, net); + err = tcindex_filter_result_init(old_r, cp, net); if (err < 0) { kfree(f); goto errout_alloc; @@ -571,6 +595,14 @@ static void tcindex_destroy(struct tcf_proto *tp, bool rtnl_held, for (i = 0; i < p->hash; i++) { struct tcindex_filter_result *r = p->perfect + i; + /* tcf_queue_work() does not guarantee the ordering we + * want, so we have to take this refcnt temporarily to + * ensure 'p' is freed after all tcindex_filter_result + * here. Imperfect hash does not need this, because it + * uses linked lists rather than an array. + */ + tcindex_data_get(p); + tcf_unbind_filter(tp, &r->res); if (tcf_exts_get_net(&r->exts)) tcf_queue_work(&r->rwork, |