zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/net/sched/sch_tbf.c b/ap/os/linux/linux-3.4.x/net/sched/sch_tbf.c
new file mode 100644
index 0000000..b8e1563
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/net/sched/sch_tbf.c
@@ -0,0 +1,465 @@
+/*
+ * net/sched/sch_tbf.c Token Bucket Filter queue.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ * Dmitry Torokhov <dtor@mail.ru> - allow attaching inner qdiscs -
+ * original idea by Martin Devera
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/skbuff.h>
+#include <net/netlink.h>
+#include <net/pkt_sched.h>
+
+
+/* Simple Token Bucket Filter.
+ =======================================
+
+ SOURCE.
+ -------
+
+ None.
+
+ Description.
+ ------------
+
+ A data flow obeys TBF with rate R and depth B, if for any
+ time interval t_i...t_f the number of transmitted bits
+ does not exceed B + R*(t_f-t_i).
+
+ Packetized version of this definition:
+ The sequence of packets of sizes s_i served at moments t_i
+ obeys TBF, if for any i<=k:
+
+ s_i+....+s_k <= B + R*(t_k - t_i)
+
+ Algorithm.
+ ----------
+
+ Let N(t_i) be B/R initially and N(t) grow continuously with time as:
+
+ N(t+delta) = min{B/R, N(t) + delta}
+
+ If the first packet in queue has length S, it may be
+ transmitted only at the time t_* when S/R <= N(t_*),
+ and in this case N(t) jumps:
+
+ N(t_* + 0) = N(t_* - 0) - S/R.
+
+
+
+ Actually, QoS requires two TBF to be applied to a data stream.
+ One of them controls steady state burst size, another
+ one with rate P (peak rate) and depth M (equal to link MTU)
+ limits bursts at a smaller time scale.
+
+ It is easy to see that P>R, and B>M. If P is infinity, this double
+ TBF is equivalent to a single one.
+
+ When TBF works in reshaping mode, latency is estimated as:
+
+ lat = max ((L-B)/R, (L-M)/P)
+
+
+ NOTES.
+ ------
+
+ If TBF throttles, it starts a watchdog timer, which will wake it up
+ when it is ready to transmit.
+ Note that the minimal timer resolution is 1/HZ.
+ If no new packets arrive during this period,
+ or if the device is not awaken by EOI for some previous packet,
+ TBF can stop its activity for 1/HZ.
+
+
+ This means, that with depth B, the maximal rate is
+
+ R_crit = B*HZ
+
+ F.e. for 10Mbit ethernet and HZ=100 the minimal allowed B is ~10Kbytes.
+
+ Note that the peak rate TBF is much more tough: with MTU 1500
+ P_crit = 150Kbytes/sec. So, if you need greater peak
+ rates, use alpha with HZ=1000 :-)
+
+ With classful TBF, limit is just kept for backwards compatibility.
+ It is passed to the default bfifo qdisc - if the inner qdisc is
+ changed the limit is not effective anymore.
+*/
+
+struct tbf_sched_data {
+/* Parameters */
+ u32 limit; /* Maximal length of backlog: bytes */
+ u32 buffer; /* Token bucket depth/rate: MUST BE >= MTU/B */
+ u32 mtu;
+ u32 max_size;
+ struct qdisc_rate_table *R_tab;
+ struct qdisc_rate_table *P_tab;
+
+/* Variables */
+ long tokens; /* Current number of B tokens */
+ long ptokens; /* Current number of P tokens */
+ psched_time_t t_c; /* Time check-point */
+ struct Qdisc *qdisc; /* Inner qdisc, default - bfifo queue */
+ struct qdisc_watchdog watchdog; /* Watchdog timer */
+};
+
+#define L2T(q, L) qdisc_l2t((q)->R_tab, L)
+#define L2T_P(q, L) qdisc_l2t((q)->P_tab, L)
+
+static int tbf_enqueue(struct sk_buff *skb, struct Qdisc *sch)
+{
+ struct tbf_sched_data *q = qdisc_priv(sch);
+ int ret;
+
+ if (qdisc_pkt_len(skb) > q->max_size)
+ return qdisc_reshape_fail(skb, sch);
+
+ ret = qdisc_enqueue(skb, q->qdisc);
+ if (ret != NET_XMIT_SUCCESS) {
+ if (net_xmit_drop_count(ret))
+ sch->qstats.drops++;
+ return ret;
+ }
+
+ sch->q.qlen++;
+ return NET_XMIT_SUCCESS;
+}
+
+static unsigned int tbf_drop(struct Qdisc *sch)
+{
+ struct tbf_sched_data *q = qdisc_priv(sch);
+ unsigned int len = 0;
+
+ if (q->qdisc->ops->drop && (len = q->qdisc->ops->drop(q->qdisc)) != 0) {
+ sch->q.qlen--;
+ sch->qstats.drops++;
+ }
+ return len;
+}
+
+static struct sk_buff *tbf_dequeue(struct Qdisc *sch)
+{
+ struct tbf_sched_data *q = qdisc_priv(sch);
+ struct sk_buff *skb;
+
+ skb = q->qdisc->ops->peek(q->qdisc);
+
+ if (skb) {
+ psched_time_t now;
+ long toks;
+ long ptoks = 0;
+ unsigned int len = qdisc_pkt_len(skb);
+
+ now = psched_get_time();
+ toks = psched_tdiff_bounded(now, q->t_c, q->buffer);
+
+ if (q->P_tab) {
+ ptoks = toks + q->ptokens;
+ if (ptoks > (long)q->mtu)
+ ptoks = q->mtu;
+ ptoks -= L2T_P(q, len);
+ }
+ toks += q->tokens;
+ if (toks > (long)q->buffer)
+ toks = q->buffer;
+ toks -= L2T(q, len);
+
+ if ((toks|ptoks) >= 0) {
+ skb = qdisc_dequeue_peeked(q->qdisc);
+ if (unlikely(!skb))
+ return NULL;
+
+ q->t_c = now;
+ q->tokens = toks;
+ q->ptokens = ptoks;
+ sch->q.qlen--;
+ qdisc_unthrottled(sch);
+ qdisc_bstats_update(sch, skb);
+ return skb;
+ }
+
+ qdisc_watchdog_schedule(&q->watchdog,
+ now + max_t(long, -toks, -ptoks));
+
+ /* Maybe we have a shorter packet in the queue,
+ which can be sent now. It sounds cool,
+ but, however, this is wrong in principle.
+ We MUST NOT reorder packets under these circumstances.
+
+ Really, if we split the flow into independent
+ subflows, it would be a very good solution.
+ This is the main idea of all FQ algorithms
+ (cf. CSZ, HPFQ, HFSC)
+ */
+
+ sch->qstats.overlimits++;
+ }
+ return NULL;
+}
+
+static void tbf_reset(struct Qdisc *sch)
+{
+ struct tbf_sched_data *q = qdisc_priv(sch);
+
+ qdisc_reset(q->qdisc);
+ sch->q.qlen = 0;
+ q->t_c = psched_get_time();
+ q->tokens = q->buffer;
+ q->ptokens = q->mtu;
+ qdisc_watchdog_cancel(&q->watchdog);
+}
+
+static const struct nla_policy tbf_policy[TCA_TBF_MAX + 1] = {
+ [TCA_TBF_PARMS] = { .len = sizeof(struct tc_tbf_qopt) },
+ [TCA_TBF_RTAB] = { .type = NLA_BINARY, .len = TC_RTAB_SIZE },
+ [TCA_TBF_PTAB] = { .type = NLA_BINARY, .len = TC_RTAB_SIZE },
+};
+
+static int tbf_change(struct Qdisc *sch, struct nlattr *opt)
+{
+ int err;
+ struct tbf_sched_data *q = qdisc_priv(sch);
+ struct nlattr *tb[TCA_TBF_PTAB + 1];
+ struct tc_tbf_qopt *qopt;
+ struct qdisc_rate_table *rtab = NULL;
+ struct qdisc_rate_table *ptab = NULL;
+ struct Qdisc *child = NULL;
+ int max_size, n;
+
+ err = nla_parse_nested(tb, TCA_TBF_PTAB, opt, tbf_policy);
+ if (err < 0)
+ return err;
+
+ err = -EINVAL;
+ if (tb[TCA_TBF_PARMS] == NULL)
+ goto done;
+
+ qopt = nla_data(tb[TCA_TBF_PARMS]);
+ rtab = qdisc_get_rtab(&qopt->rate, tb[TCA_TBF_RTAB]);
+ if (rtab == NULL)
+ goto done;
+
+ if (qopt->peakrate.rate) {
+ if (qopt->peakrate.rate > qopt->rate.rate)
+ ptab = qdisc_get_rtab(&qopt->peakrate, tb[TCA_TBF_PTAB]);
+ if (ptab == NULL)
+ goto done;
+ }
+
+ for (n = 0; n < 256; n++)
+ if (rtab->data[n] > qopt->buffer)
+ break;
+ max_size = (n << qopt->rate.cell_log) - 1;
+ if (ptab) {
+ int size;
+
+ for (n = 0; n < 256; n++)
+ if (ptab->data[n] > qopt->mtu)
+ break;
+ size = (n << qopt->peakrate.cell_log) - 1;
+ if (size < max_size)
+ max_size = size;
+ }
+ if (max_size < 0)
+ goto done;
+
+ if (q->qdisc != &noop_qdisc) {
+ err = fifo_set_limit(q->qdisc, qopt->limit);
+ if (err)
+ goto done;
+ } else if (qopt->limit > 0) {
+ child = fifo_create_dflt(sch, &bfifo_qdisc_ops, qopt->limit);
+ if (IS_ERR(child)) {
+ err = PTR_ERR(child);
+ goto done;
+ }
+ }
+
+ sch_tree_lock(sch);
+ if (child) {
+ qdisc_tree_decrease_qlen(q->qdisc, q->qdisc->q.qlen);
+ qdisc_destroy(q->qdisc);
+ q->qdisc = child;
+ }
+ q->limit = qopt->limit;
+ q->mtu = qopt->mtu;
+ q->max_size = max_size;
+ q->buffer = qopt->buffer;
+ q->tokens = q->buffer;
+ q->ptokens = q->mtu;
+
+ swap(q->R_tab, rtab);
+ swap(q->P_tab, ptab);
+
+ sch_tree_unlock(sch);
+ err = 0;
+done:
+ if (rtab)
+ qdisc_put_rtab(rtab);
+ if (ptab)
+ qdisc_put_rtab(ptab);
+ return err;
+}
+
+static int tbf_init(struct Qdisc *sch, struct nlattr *opt)
+{
+ struct tbf_sched_data *q = qdisc_priv(sch);
+
+ if (opt == NULL)
+ return -EINVAL;
+
+ q->t_c = psched_get_time();
+ qdisc_watchdog_init(&q->watchdog, sch);
+ q->qdisc = &noop_qdisc;
+
+ return tbf_change(sch, opt);
+}
+
+static void tbf_destroy(struct Qdisc *sch)
+{
+ struct tbf_sched_data *q = qdisc_priv(sch);
+
+ qdisc_watchdog_cancel(&q->watchdog);
+
+ if (q->P_tab)
+ qdisc_put_rtab(q->P_tab);
+ if (q->R_tab)
+ qdisc_put_rtab(q->R_tab);
+
+ qdisc_destroy(q->qdisc);
+}
+
+static int tbf_dump(struct Qdisc *sch, struct sk_buff *skb)
+{
+ struct tbf_sched_data *q = qdisc_priv(sch);
+ struct nlattr *nest;
+ struct tc_tbf_qopt opt;
+
+ sch->qstats.backlog = q->qdisc->qstats.backlog;
+ nest = nla_nest_start(skb, TCA_OPTIONS);
+ if (nest == NULL)
+ goto nla_put_failure;
+
+ opt.limit = q->limit;
+ opt.rate = q->R_tab->rate;
+ if (q->P_tab)
+ opt.peakrate = q->P_tab->rate;
+ else
+ memset(&opt.peakrate, 0, sizeof(opt.peakrate));
+ opt.mtu = q->mtu;
+ opt.buffer = q->buffer;
+ NLA_PUT(skb, TCA_TBF_PARMS, sizeof(opt), &opt);
+
+ nla_nest_end(skb, nest);
+ return skb->len;
+
+nla_put_failure:
+ nla_nest_cancel(skb, nest);
+ return -1;
+}
+
+static int tbf_dump_class(struct Qdisc *sch, unsigned long cl,
+ struct sk_buff *skb, struct tcmsg *tcm)
+{
+ struct tbf_sched_data *q = qdisc_priv(sch);
+
+ tcm->tcm_handle |= TC_H_MIN(1);
+ tcm->tcm_info = q->qdisc->handle;
+
+ return 0;
+}
+
+static int tbf_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
+ struct Qdisc **old)
+{
+ struct tbf_sched_data *q = qdisc_priv(sch);
+
+ if (new == NULL)
+ new = &noop_qdisc;
+
+ sch_tree_lock(sch);
+ *old = q->qdisc;
+ q->qdisc = new;
+ qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
+ qdisc_reset(*old);
+ sch_tree_unlock(sch);
+
+ return 0;
+}
+
+static struct Qdisc *tbf_leaf(struct Qdisc *sch, unsigned long arg)
+{
+ struct tbf_sched_data *q = qdisc_priv(sch);
+ return q->qdisc;
+}
+
+static unsigned long tbf_get(struct Qdisc *sch, u32 classid)
+{
+ return 1;
+}
+
+static void tbf_put(struct Qdisc *sch, unsigned long arg)
+{
+}
+
+static void tbf_walk(struct Qdisc *sch, struct qdisc_walker *walker)
+{
+ if (!walker->stop) {
+ if (walker->count >= walker->skip)
+ if (walker->fn(sch, 1, walker) < 0) {
+ walker->stop = 1;
+ return;
+ }
+ walker->count++;
+ }
+}
+
+static const struct Qdisc_class_ops tbf_class_ops = {
+ .graft = tbf_graft,
+ .leaf = tbf_leaf,
+ .get = tbf_get,
+ .put = tbf_put,
+ .walk = tbf_walk,
+ .dump = tbf_dump_class,
+};
+
+static struct Qdisc_ops tbf_qdisc_ops __read_mostly = {
+ .next = NULL,
+ .cl_ops = &tbf_class_ops,
+ .id = "tbf",
+ .priv_size = sizeof(struct tbf_sched_data),
+ .enqueue = tbf_enqueue,
+ .dequeue = tbf_dequeue,
+ .peek = qdisc_peek_dequeued,
+ .drop = tbf_drop,
+ .init = tbf_init,
+ .reset = tbf_reset,
+ .destroy = tbf_destroy,
+ .change = tbf_change,
+ .dump = tbf_dump,
+ .owner = THIS_MODULE,
+};
+
+static int __init tbf_module_init(void)
+{
+ return register_qdisc(&tbf_qdisc_ops);
+}
+
+static void __exit tbf_module_exit(void)
+{
+ unregister_qdisc(&tbf_qdisc_ops);
+}
+module_init(tbf_module_init)
+module_exit(tbf_module_exit)
+MODULE_LICENSE("GPL");