diff options
-rw-r--r-- | include/net/red.h | 33 | ||||
-rw-r--r-- | include/uapi/linux/pkt_sched.h | 16 | ||||
-rw-r--r-- | net/sched/sch_red.c | 43 |
3 files changed, 89 insertions, 3 deletions
diff --git a/include/net/red.h b/include/net/red.h index 9665582c4687..6a2aaa6c7c41 100644 --- a/include/net/red.h +++ b/include/net/red.h @@ -179,6 +179,39 @@ static inline bool red_check_params(u32 qth_min, u32 qth_max, u8 Wlog) return true; } +static inline int red_get_flags(unsigned char qopt_flags, + unsigned char historic_mask, + struct nlattr *flags_attr, + unsigned char supported_mask, + struct nla_bitfield32 *p_flags, + unsigned char *p_userbits, + struct netlink_ext_ack *extack) +{ + struct nla_bitfield32 flags; + + if (qopt_flags && flags_attr) { + NL_SET_ERR_MSG_MOD(extack, "flags should be passed either through qopt, or through a dedicated attribute"); + return -EINVAL; + } + + if (flags_attr) { + flags = nla_get_bitfield32(flags_attr); + } else { + flags.selector = historic_mask; + flags.value = qopt_flags & historic_mask; + } + + *p_flags = flags; + *p_userbits = qopt_flags & ~historic_mask; + return 0; +} + +static inline int red_validate_flags(unsigned char flags, + struct netlink_ext_ack *extack) +{ + return 0; +} + static inline void red_set_parms(struct red_parms *p, u32 qth_min, u32 qth_max, u8 Wlog, u8 Plog, u8 Scell_log, u8 *stab, u32 max_P) diff --git a/include/uapi/linux/pkt_sched.h b/include/uapi/linux/pkt_sched.h index bbe791b24168..6325507935ea 100644 --- a/include/uapi/linux/pkt_sched.h +++ b/include/uapi/linux/pkt_sched.h @@ -256,6 +256,7 @@ enum { TCA_RED_PARMS, TCA_RED_STAB, TCA_RED_MAX_P, + TCA_RED_FLAGS, /* bitfield32 */ __TCA_RED_MAX, }; @@ -268,12 +269,27 @@ struct tc_red_qopt { unsigned char Wlog; /* log(W) */ unsigned char Plog; /* log(P_max/(qth_max-qth_min)) */ unsigned char Scell_log; /* cell size for idle damping */ + + /* This field can be used for flags that a RED-like qdisc has + * historically supported. E.g. when configuring RED, it can be used for + * ECN, HARDDROP and ADAPTATIVE. For SFQ it can be used for ECN, + * HARDDROP. Etc. Because this field has not been validated, and is + * copied back on dump, any bits besides those to which a given qdisc + * has assigned a historical meaning need to be considered for free use + * by userspace tools. + * + * Any further flags need to be passed differently, e.g. through an + * attribute (such as TCA_RED_FLAGS above). Such attribute should allow + * passing both recent and historic flags in one value. + */ unsigned char flags; #define TC_RED_ECN 1 #define TC_RED_HARDDROP 2 #define TC_RED_ADAPTATIVE 4 }; +#define TC_RED_HISTORIC_FLAGS (TC_RED_ECN | TC_RED_HARDDROP | TC_RED_ADAPTATIVE) + struct tc_red_xstats { __u32 early; /* Early drops */ __u32 pdrop; /* Drops due to queue limits */ diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c index 1695421333e3..d4ce111704dc 100644 --- a/net/sched/sch_red.c +++ b/net/sched/sch_red.c @@ -35,7 +35,11 @@ struct red_sched_data { u32 limit; /* HARD maximal queue length */ + unsigned char flags; + /* Non-flags in tc_red_qopt.flags. */ + unsigned char userbits; + struct timer_list adapt_timer; struct Qdisc *sch; struct red_parms parms; @@ -44,6 +48,8 @@ struct red_sched_data { struct Qdisc *qdisc; }; +static const u32 red_supported_flags = TC_RED_HISTORIC_FLAGS; + static inline int red_use_ecn(struct red_sched_data *q) { return q->flags & TC_RED_ECN; @@ -183,9 +189,12 @@ static void red_destroy(struct Qdisc *sch) } static const struct nla_policy red_policy[TCA_RED_MAX + 1] = { + [TCA_RED_UNSPEC] = { .strict_start_type = TCA_RED_FLAGS }, [TCA_RED_PARMS] = { .len = sizeof(struct tc_red_qopt) }, [TCA_RED_STAB] = { .len = RED_STAB_SIZE }, [TCA_RED_MAX_P] = { .type = NLA_U32 }, + [TCA_RED_FLAGS] = { .type = NLA_BITFIELD32, + .validation_data = &red_supported_flags }, }; static int red_change(struct Qdisc *sch, struct nlattr *opt, @@ -194,7 +203,10 @@ static int red_change(struct Qdisc *sch, struct nlattr *opt, struct Qdisc *old_child = NULL, *child = NULL; struct red_sched_data *q = qdisc_priv(sch); struct nlattr *tb[TCA_RED_MAX + 1]; + struct nla_bitfield32 flags_bf; struct tc_red_qopt *ctl; + unsigned char userbits; + unsigned char flags; int err; u32 max_P; @@ -216,6 +228,12 @@ static int red_change(struct Qdisc *sch, struct nlattr *opt, if (!red_check_params(ctl->qth_min, ctl->qth_max, ctl->Wlog)) return -EINVAL; + err = red_get_flags(ctl->flags, TC_RED_HISTORIC_FLAGS, + tb[TCA_RED_FLAGS], red_supported_flags, + &flags_bf, &userbits, extack); + if (err) + return err; + if (ctl->limit > 0) { child = fifo_create_dflt(sch, &bfifo_qdisc_ops, ctl->limit, extack); @@ -227,7 +245,14 @@ static int red_change(struct Qdisc *sch, struct nlattr *opt, } sch_tree_lock(sch); - q->flags = ctl->flags; + + flags = (q->flags & ~flags_bf.selector) | flags_bf.value; + err = red_validate_flags(flags, extack); + if (err) + goto unlock_out; + + q->flags = flags; + q->userbits = userbits; q->limit = ctl->limit; if (child) { qdisc_tree_flush_backlog(q->qdisc); @@ -256,6 +281,12 @@ static int red_change(struct Qdisc *sch, struct nlattr *opt, if (old_child) qdisc_put(old_child); return 0; + +unlock_out: + sch_tree_unlock(sch); + if (child) + qdisc_put(child); + return err; } static inline void red_adaptative_timer(struct timer_list *t) @@ -299,10 +330,15 @@ static int red_dump_offload_stats(struct Qdisc *sch) static int red_dump(struct Qdisc *sch, struct sk_buff *skb) { struct red_sched_data *q = qdisc_priv(sch); + struct nla_bitfield32 flags_bf = { + .selector = red_supported_flags, + .value = q->flags, + }; struct nlattr *opts = NULL; struct tc_red_qopt opt = { .limit = q->limit, - .flags = q->flags, + .flags = (q->flags & TC_RED_HISTORIC_FLAGS) | + q->userbits, .qth_min = q->parms.qth_min >> q->parms.Wlog, .qth_max = q->parms.qth_max >> q->parms.Wlog, .Wlog = q->parms.Wlog, @@ -319,7 +355,8 @@ static int red_dump(struct Qdisc *sch, struct sk_buff *skb) if (opts == NULL) goto nla_put_failure; if (nla_put(skb, TCA_RED_PARMS, sizeof(opt), &opt) || - nla_put_u32(skb, TCA_RED_MAX_P, q->parms.max_P)) + nla_put_u32(skb, TCA_RED_MAX_P, q->parms.max_P) || + nla_put(skb, TCA_RED_FLAGS, sizeof(flags_bf), &flags_bf)) goto nla_put_failure; return nla_nest_end(skb, opts); |