diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index ad0dadcfcdba..e2d4283bea6d 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -31,6 +31,7 @@ static DEFINE_SPINLOCK(taprio_list_lock); #define TXTIME_ASSIST_IS_ENABLED(flags) ((flags) & TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST) #define FULL_OFFLOAD_IS_ENABLED(flags) ((flags) & TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD) +#define TAPRIO_FLAGS_INVALID U32_MAX struct sched_entry { struct list_head list; @@ -1367,6 +1368,33 @@ static int taprio_mqprio_cmp(const struct net_device *dev, return 0; } +/* The semantics of the 'flags' argument in relation to 'change()' + * requests, are interpreted following two rules (which are applied in + * this order): (1) an omitted 'flags' argument is interpreted as + * zero; (2) the 'flags' of a "running" taprio instance cannot be + * changed. + */ +static int taprio_new_flags(const struct nlattr *attr, u32 old, + struct netlink_ext_ack *extack) +{ + u32 new = 0; + + if (attr) + new = nla_get_u32(attr); + + if (old != TAPRIO_FLAGS_INVALID && old != new) { + NL_SET_ERR_MSG_MOD(extack, "Changing 'flags' of a running schedule is not supported"); + return -EOPNOTSUPP; + } + + if (!taprio_flags_valid(new)) { + NL_SET_ERR_MSG_MOD(extack, "Specified 'flags' are not valid"); + return -EINVAL; + } + + return new; +} + static int taprio_change(struct Qdisc *sch, struct nlattr *opt, struct netlink_ext_ack *extack) { @@ -1375,7 +1403,6 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, struct taprio_sched *q = qdisc_priv(sch); struct net_device *dev = qdisc_dev(sch); struct tc_mqprio_qopt *mqprio = NULL; - u32 taprio_flags = 0; unsigned long flags; ktime_t start; int i, err; @@ -1388,21 +1415,14 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, if (tb[TCA_TAPRIO_ATTR_PRIOMAP]) mqprio = nla_data(tb[TCA_TAPRIO_ATTR_PRIOMAP]); - if (tb[TCA_TAPRIO_ATTR_FLAGS]) { - taprio_flags = nla_get_u32(tb[TCA_TAPRIO_ATTR_FLAGS]); + err = taprio_new_flags(tb[TCA_TAPRIO_ATTR_FLAGS], + q->flags, extack); + if (err < 0) + return err; - if (q->flags != 0 && q->flags != taprio_flags) { - NL_SET_ERR_MSG_MOD(extack, "Changing 'flags' of a running schedule is not supported"); - return -EOPNOTSUPP; - } else if (!taprio_flags_valid(taprio_flags)) { - NL_SET_ERR_MSG_MOD(extack, "Specified 'flags' are not valid"); - return -EINVAL; - } + q->flags = err; - q->flags = taprio_flags; - } - - err = taprio_parse_mqprio_opt(dev, mqprio, extack, taprio_flags); + err = taprio_parse_mqprio_opt(dev, mqprio, extack, q->flags); if (err < 0) return err; @@ -1457,7 +1477,7 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, mqprio->prio_tc_map[i]); } - if (FULL_OFFLOAD_IS_ENABLED(taprio_flags)) + if (FULL_OFFLOAD_IS_ENABLED(q->flags)) err = taprio_enable_offload(dev, mqprio, q, new_admin, extack); else err = taprio_disable_offload(dev, q, extack); @@ -1477,14 +1497,14 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, q->txtime_delay = nla_get_u32(tb[TCA_TAPRIO_ATTR_TXTIME_DELAY]); } - if (!TXTIME_ASSIST_IS_ENABLED(taprio_flags) && - !FULL_OFFLOAD_IS_ENABLED(taprio_flags) && + if (!TXTIME_ASSIST_IS_ENABLED(q->flags) && + !FULL_OFFLOAD_IS_ENABLED(q->flags) && !hrtimer_active(&q->advance_timer)) { hrtimer_init(&q->advance_timer, q->clockid, HRTIMER_MODE_ABS); q->advance_timer.function = advance_sched; } - if (FULL_OFFLOAD_IS_ENABLED(taprio_flags)) { + if (FULL_OFFLOAD_IS_ENABLED(q->flags)) { q->dequeue = taprio_dequeue_offload; q->peek = taprio_peek_offload; } else { @@ -1501,7 +1521,7 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, goto unlock; } - if (TXTIME_ASSIST_IS_ENABLED(taprio_flags)) { + if (TXTIME_ASSIST_IS_ENABLED(q->flags)) { setup_txtime(q, new_admin, start); if (!oper) { @@ -1528,7 +1548,7 @@ static int taprio_change(struct Qdisc *sch, struct nlattr *opt, spin_unlock_irqrestore(&q->current_entry_lock, flags); - if (FULL_OFFLOAD_IS_ENABLED(taprio_flags)) + if (FULL_OFFLOAD_IS_ENABLED(q->flags)) taprio_offload_config_changed(q); } @@ -1597,6 +1617,7 @@ static int taprio_init(struct Qdisc *sch, struct nlattr *opt, * and get the valid one on taprio_change(). */ q->clockid = -1; + q->flags = TAPRIO_FLAGS_INVALID; spin_lock(&taprio_list_lock); list_add(&q->taprio_list, &taprio_list);