+static void
+htb_parse_qdisc_details__(struct netdev *netdev,
+ const struct shash *details, struct htb_class *hc)
+{
+ const char *max_rate_s;
+
+ max_rate_s = shash_find_data(details, "max-rate");
+ hc->max_rate = max_rate_s ? strtoull(max_rate_s, NULL, 10) / 8 : 0;
+ if (!hc->max_rate) {
+ uint32_t current;
+
+ netdev_get_features(netdev, ¤t, NULL, NULL, NULL);
+ hc->max_rate = netdev_features_to_bps(current) / 8;
+ }
+ hc->min_rate = hc->max_rate;
+ hc->burst = 0;
+ hc->priority = 0;
+}
+
+static int
+htb_parse_class_details__(struct netdev *netdev,
+ const struct shash *details, struct htb_class *hc)
+{
+ const struct htb *htb = htb_get__(netdev);
+ const char *min_rate_s = shash_find_data(details, "min-rate");
+ const char *max_rate_s = shash_find_data(details, "max-rate");
+ const char *burst_s = shash_find_data(details, "burst");
+ const char *priority_s = shash_find_data(details, "priority");
+ int mtu;
+
+ /* min-rate */
+ if (!min_rate_s) {
+ /* min-rate is required. */
+ return EINVAL;
+ }
+ hc->min_rate = strtoull(min_rate_s, NULL, 10) / 8;
+ hc->min_rate = MAX(hc->min_rate, 0);
+ hc->min_rate = MIN(hc->min_rate, htb->max_rate);
+
+ /* max-rate */
+ hc->max_rate = (max_rate_s
+ ? strtoull(max_rate_s, NULL, 10) / 8
+ : htb->max_rate);
+ hc->max_rate = MAX(hc->max_rate, hc->min_rate);
+ hc->max_rate = MIN(hc->max_rate, htb->max_rate);
+
+ /* burst
+ *
+ * According to hints in the documentation that I've read, it is important
+ * that 'burst' be at least as big as the largest frame that might be
+ * transmitted. Also, making 'burst' a bit bigger than necessary is OK,
+ * but having it a bit too small is a problem. Since netdev_get_mtu()
+ * doesn't include the Ethernet header, we need to add at least 14 (18?) to
+ * the MTU. We actually add 64, instead of 14, as a guard against
+ * additional headers get tacked on somewhere that we're not aware of. */
+ netdev_get_mtu(netdev, &mtu);
+ hc->burst = burst_s ? strtoull(burst_s, NULL, 10) / 8 : 0;
+ hc->burst = MAX(hc->burst, mtu + 64);
+
+ /* priority */
+ hc->priority = priority_s ? strtoul(priority_s, NULL, 10) : 0;
+
+ return 0;
+}
+
+static int
+htb_query_class__(const struct netdev *netdev, unsigned int handle,
+ unsigned int parent, struct htb_class *options,
+ struct netdev_queue_stats *stats)
+{
+ struct ofpbuf *reply;
+ int error;
+
+ error = tc_query_class(netdev, handle, parent, &reply);
+ if (!error) {
+ error = htb_parse_tcmsg__(reply, NULL, options, stats);
+ ofpbuf_delete(reply);
+ }
+ return error;
+}
+
+static int
+htb_tc_install(struct netdev *netdev, const struct shash *details)
+{
+ int error;
+
+ error = htb_setup_qdisc__(netdev);
+ if (!error) {
+ struct htb_class hc;
+
+ htb_parse_qdisc_details__(netdev, details, &hc);
+ error = htb_setup_class__(netdev, tc_make_handle(1, 0xfffe),
+ tc_make_handle(1, 0), &hc);
+ if (!error) {
+ htb_install__(netdev, hc.max_rate);
+ }
+ }
+ return error;
+}
+
+static struct htb_class *
+htb_class_cast__(const struct tc_queue *queue)
+{
+ return CONTAINER_OF(queue, struct htb_class, tc_queue);
+}
+
+static void
+htb_update_queue__(struct netdev *netdev, unsigned int queue_id,
+ const struct htb_class *hc)
+{
+ struct htb *htb = htb_get__(netdev);
+ size_t hash = hash_int(queue_id, 0);
+ struct tc_queue *queue;
+ struct htb_class *hcp;
+
+ queue = tc_find_queue__(netdev, queue_id, hash);
+ if (queue) {
+ hcp = htb_class_cast__(queue);
+ } else {
+ hcp = xmalloc(sizeof *hcp);
+ queue = &hcp->tc_queue;
+ queue->queue_id = queue_id;
+ hmap_insert(&htb->tc.queues, &queue->hmap_node, hash);
+ }
+
+ hcp->min_rate = hc->min_rate;
+ hcp->max_rate = hc->max_rate;
+ hcp->burst = hc->burst;
+ hcp->priority = hc->priority;
+}
+
+static int
+htb_tc_load(struct netdev *netdev, struct ofpbuf *nlmsg OVS_UNUSED)
+{
+ struct shash details = SHASH_INITIALIZER(&details);
+ struct ofpbuf msg;
+ struct nl_dump dump;
+ struct htb_class hc;
+ struct htb *htb;
+
+ /* Get qdisc options. */
+ hc.max_rate = 0;
+ htb_query_class__(netdev, tc_make_handle(1, 0xfffe), 0, &hc, NULL);
+ htb = htb_install__(netdev, hc.max_rate);
+
+ /* Get queues. */
+ start_queue_dump(netdev, &dump);
+ shash_init(&details);
+ while (nl_dump_next(&dump, &msg)) {
+ unsigned int queue_id;
+
+ if (!htb_parse_tcmsg__(&msg, &queue_id, &hc, NULL)) {
+ htb_update_queue__(netdev, queue_id, &hc);
+ }
+ }
+ nl_dump_done(&dump);
+
+ return 0;
+}
+
+static void
+htb_tc_destroy(struct tc *tc)
+{
+ struct htb *htb = CONTAINER_OF(tc, struct htb, tc);
+ struct htb_class *hc, *next;
+
+ HMAP_FOR_EACH_SAFE (hc, next, tc_queue.hmap_node, &htb->tc.queues) {
+ hmap_remove(&htb->tc.queues, &hc->tc_queue.hmap_node);
+ free(hc);
+ }
+ tc_destroy(tc);
+ free(htb);
+}
+
+static int
+htb_qdisc_get(const struct netdev *netdev, struct shash *details)
+{
+ const struct htb *htb = htb_get__(netdev);
+ shash_add(details, "max-rate", xasprintf("%llu", 8ULL * htb->max_rate));
+ return 0;
+}
+
+static int
+htb_qdisc_set(struct netdev *netdev, const struct shash *details)
+{
+ struct htb_class hc;
+ int error;
+
+ htb_parse_qdisc_details__(netdev, details, &hc);
+ error = htb_setup_class__(netdev, tc_make_handle(1, 0xfffe),
+ tc_make_handle(1, 0), &hc);
+ if (!error) {
+ htb_get__(netdev)->max_rate = hc.max_rate;
+ }
+ return error;
+}
+
+static int
+htb_class_get(const struct netdev *netdev OVS_UNUSED,
+ const struct tc_queue *queue, struct shash *details)
+{
+ const struct htb_class *hc = htb_class_cast__(queue);
+
+ shash_add(details, "min-rate", xasprintf("%llu", 8ULL * hc->min_rate));
+ if (hc->min_rate != hc->max_rate) {
+ shash_add(details, "max-rate", xasprintf("%llu", 8ULL * hc->max_rate));
+ }
+ shash_add(details, "burst", xasprintf("%llu", 8ULL * hc->burst));
+ if (hc->priority) {
+ shash_add(details, "priority", xasprintf("%u", hc->priority));
+ }
+ return 0;
+}
+
+static int
+htb_class_set(struct netdev *netdev, unsigned int queue_id,
+ const struct shash *details)
+{
+ struct htb_class hc;
+ int error;
+
+ error = htb_parse_class_details__(netdev, details, &hc);
+ if (error) {
+ return error;
+ }
+
+ error = htb_setup_class__(netdev, tc_make_handle(1, queue_id + 1),
+ tc_make_handle(1, 0xfffe), &hc);
+ if (error) {
+ return error;
+ }
+
+ htb_update_queue__(netdev, queue_id, &hc);
+ return 0;
+}
+
+static int
+htb_class_delete(struct netdev *netdev, struct tc_queue *queue)
+{
+ struct htb_class *hc = htb_class_cast__(queue);
+ struct htb *htb = htb_get__(netdev);
+ int error;
+
+ error = tc_delete_class(netdev, tc_make_handle(1, queue->queue_id + 1));
+ if (!error) {
+ hmap_remove(&htb->tc.queues, &hc->tc_queue.hmap_node);
+ free(hc);
+ }
+ return error;
+}
+
+static int
+htb_class_get_stats(const struct netdev *netdev, const struct tc_queue *queue,
+ struct netdev_queue_stats *stats)
+{
+ return htb_query_class__(netdev, tc_make_handle(1, queue->queue_id + 1),
+ tc_make_handle(1, 0xfffe), NULL, stats);
+}
+
+static int
+htb_class_dump_stats(const struct netdev *netdev OVS_UNUSED,
+ const struct ofpbuf *nlmsg,
+ netdev_dump_queue_stats_cb *cb, void *aux)
+{
+ struct netdev_queue_stats stats;
+ unsigned int handle, major, minor;
+ int error;
+
+ error = tc_parse_class(nlmsg, &handle, NULL, &stats);
+ if (error) {
+ return error;
+ }
+
+ major = tc_get_major(handle);
+ minor = tc_get_minor(handle);
+ if (major == 1 && minor > 0 && minor <= HTB_N_QUEUES) {
+ (*cb)(minor - 1, &stats, aux);
+ }
+ return 0;
+}
+
+static const struct tc_ops tc_ops_htb = {
+ "htb", /* linux_name */
+ "linux-htb", /* ovs_name */
+ HTB_N_QUEUES, /* n_queues */
+ htb_tc_install,
+ htb_tc_load,
+ htb_tc_destroy,
+ htb_qdisc_get,
+ htb_qdisc_set,
+ htb_class_get,
+ htb_class_set,
+ htb_class_delete,
+ htb_class_get_stats,
+ htb_class_dump_stats
+};
+\f
+/* "linux-default" traffic control class.
+ *
+ * This class represents the default, unnamed Linux qdisc. It corresponds to
+ * the "" (empty string) QoS type in the OVS database. */
+
+static void
+default_install__(struct netdev *netdev)
+{
+ struct netdev_dev_linux *netdev_dev =
+ netdev_dev_linux_cast(netdev_get_dev(netdev));
+ static struct tc *tc;
+
+ if (!tc) {
+ tc = xmalloc(sizeof *tc);
+ tc_init(tc, &tc_ops_default);
+ }
+ netdev_dev->tc = tc;
+}
+
+static int
+default_tc_install(struct netdev *netdev,
+ const struct shash *details OVS_UNUSED)
+{
+ default_install__(netdev);
+ return 0;
+}
+
+static int
+default_tc_load(struct netdev *netdev, struct ofpbuf *nlmsg OVS_UNUSED)
+{
+ default_install__(netdev);
+ return 0;
+}
+
+static const struct tc_ops tc_ops_default = {
+ NULL, /* linux_name */
+ "", /* ovs_name */
+ 0, /* n_queues */
+ default_tc_install,
+ default_tc_load,
+ NULL, /* tc_destroy */
+ NULL, /* qdisc_get */
+ NULL, /* qdisc_set */
+ NULL, /* class_get */
+ NULL, /* class_set */
+ NULL, /* class_delete */
+ NULL, /* class_get_stats */
+ NULL /* class_dump_stats */
+};
+\f
+/* "linux-other" traffic control class.
+ *
+ * */
+
+static int
+other_tc_load(struct netdev *netdev, struct ofpbuf *nlmsg OVS_UNUSED)
+{
+ struct netdev_dev_linux *netdev_dev =
+ netdev_dev_linux_cast(netdev_get_dev(netdev));
+ static struct tc *tc;
+
+ if (!tc) {
+ tc = xmalloc(sizeof *tc);
+ tc_init(tc, &tc_ops_other);
+ }
+ netdev_dev->tc = tc;
+ return 0;
+}
+
+static const struct tc_ops tc_ops_other = {
+ NULL, /* linux_name */
+ "linux-other", /* ovs_name */
+ 0, /* n_queues */
+ NULL, /* tc_install */
+ other_tc_load,
+ NULL, /* tc_destroy */
+ NULL, /* qdisc_get */
+ NULL, /* qdisc_set */
+ NULL, /* class_get */
+ NULL, /* class_set */
+ NULL, /* class_delete */
+ NULL, /* class_get_stats */
+ NULL /* class_dump_stats */
+};
+\f
+/* Traffic control. */
+
+/* Number of kernel "tc" ticks per second. */
+static double ticks_per_s;
+
+/* Number of kernel "jiffies" per second. This is used for the purpose of
+ * computing buffer sizes. Generally kernel qdiscs need to be able to buffer
+ * one jiffy's worth of data.
+ *
+ * There are two possibilities here:
+ *
+ * - 'buffer_hz' is the kernel's real timer tick rate, a small number in the
+ * approximate range of 100 to 1024. That means that we really need to
+ * make sure that the qdisc can buffer that much data.
+ *
+ * - 'buffer_hz' is an absurdly large number. That means that the kernel
+ * has finely granular timers and there's no need to fudge additional room
+ * for buffers. (There's no extra effort needed to implement that: the
+ * large 'buffer_hz' is used as a divisor, so practically any number will
+ * come out as 0 in the division. Small integer results in the case of
+ * really high dividends won't have any real effect anyhow.)
+ */
+static unsigned int buffer_hz;
+
+/* Returns tc handle 'major':'minor'. */
+static unsigned int
+tc_make_handle(unsigned int major, unsigned int minor)
+{
+ return TC_H_MAKE(major << 16, minor);
+}
+
+/* Returns the major number from 'handle'. */
+static unsigned int
+tc_get_major(unsigned int handle)
+{
+ return TC_H_MAJ(handle) >> 16;
+}
+
+/* Returns the minor number from 'handle'. */
+static unsigned int
+tc_get_minor(unsigned int handle)
+{
+ return TC_H_MIN(handle);
+}
+
+static struct tcmsg *
+tc_make_request(const struct netdev *netdev, int type, unsigned int flags,
+ struct ofpbuf *request)
+{
+ struct tcmsg *tcmsg;
+ int ifindex;
+ int error;
+
+ error = get_ifindex(netdev, &ifindex);
+ if (error) {
+ return NULL;
+ }
+
+ ofpbuf_init(request, 512);
+ nl_msg_put_nlmsghdr(request, sizeof *tcmsg, type, NLM_F_REQUEST | flags);
+ tcmsg = ofpbuf_put_zeros(request, sizeof *tcmsg);
+ tcmsg->tcm_family = AF_UNSPEC;
+ tcmsg->tcm_ifindex = ifindex;
+ /* Caller should fill in tcmsg->tcm_handle. */
+ /* Caller should fill in tcmsg->tcm_parent. */
+
+ return tcmsg;
+}
+
+static int
+tc_transact(struct ofpbuf *request, struct ofpbuf **replyp)
+{
+ int error = nl_sock_transact(rtnl_sock, request, replyp);
+ ofpbuf_uninit(request);
+ return error;
+}
+
+static void
+read_psched(void)
+{
+ /* The values in psched are not individually very meaningful, but they are
+ * important. The tables below show some values seen in the wild.
+ *
+ * Some notes:
+ *
+ * - "c" has always been a constant 1000000 since at least Linux 2.4.14.
+ * (Before that, there are hints that it was 1000000000.)
+ *
+ * - "d" can be unrealistically large, see the comment on 'buffer_hz'
+ * above.
+ *
+ * /proc/net/psched
+ * -----------------------------------
+ * [1] 000c8000 000f4240 000f4240 00000064
+ * [2] 000003e8 00000400 000f4240 3b9aca00
+ * [3] 000003e8 00000400 000f4240 3b9aca00
+ * [4] 000003e8 00000400 000f4240 00000064
+ * [5] 000003e8 00000040 000f4240 3b9aca00
+ * [6] 000003e8 00000040 000f4240 000000f9
+ *
+ * a b c d ticks_per_s buffer_hz
+ * ------- --------- ---------- ------------- ----------- -------------
+ * [1] 819,200 1,000,000 1,000,000 100 819,200 100
+ * [2] 1,000 1,024 1,000,000 1,000,000,000 976,562 1,000,000,000
+ * [3] 1,000 1,024 1,000,000 1,000,000,000 976,562 1,000,000,000
+ * [4] 1,000 1,024 1,000,000 100 976,562 100
+ * [5] 1,000 64 1,000,000 1,000,000,000 15,625,000 1,000,000,000
+ * [6] 1,000 64 1,000,000 249 15,625,000 249
+ *
+ * [1] 2.6.18-128.1.6.el5.xs5.5.0.505.1024xen from XenServer 5.5.0-24648p
+ * [2] 2.6.26-1-686-bigmem from Debian lenny
+ * [3] 2.6.26-2-sparc64 from Debian lenny
+ * [4] 2.6.27.42-0.1.1.xs5.6.810.44.111163xen from XenServer 5.6.810-31078p
+ * [5] 2.6.32.21.22 (approx.) from Ubuntu 10.04 on VMware Fusion
+ * [6] 2.6.34 from kernel.org on KVM
+ */
+ static const char fn[] = "/proc/net/psched";
+ unsigned int a, b, c, d;
+ FILE *stream;
+
+ ticks_per_s = 1.0;
+ buffer_hz = 100;
+
+ stream = fopen(fn, "r");
+ if (!stream) {
+ VLOG_WARN("%s: open failed: %s", fn, strerror(errno));
+ return;
+ }
+
+ if (fscanf(stream, "%x %x %x %x", &a, &b, &c, &d) != 4) {
+ VLOG_WARN("%s: read failed", fn);
+ fclose(stream);
+ return;
+ }
+ VLOG_DBG("%s: psched parameters are: %u %u %u %u", fn, a, b, c, d);
+ fclose(stream);
+
+ if (!a || !c) {
+ VLOG_WARN("%s: invalid scheduler parameters", fn);
+ return;
+ }
+
+ ticks_per_s = (double) a * c / b;
+ if (c == 1000000) {
+ buffer_hz = d;
+ } else {
+ VLOG_WARN("%s: unexpected psched parameters: %u %u %u %u",
+ fn, a, b, c, d);
+ }
+ VLOG_DBG("%s: ticks_per_s=%f buffer_hz=%u", fn, ticks_per_s, buffer_hz);
+}
+
+/* Returns the number of bytes that can be transmitted in 'ticks' ticks at a
+ * rate of 'rate' bytes per second. */
+static unsigned int
+tc_ticks_to_bytes(unsigned int rate, unsigned int ticks)
+{
+ if (!buffer_hz) {
+ read_psched();
+ }
+ return (rate * ticks) / ticks_per_s;
+}
+
+/* Returns the number of ticks that it would take to transmit 'size' bytes at a
+ * rate of 'rate' bytes per second. */
+static unsigned int
+tc_bytes_to_ticks(unsigned int rate, unsigned int size)
+{
+ if (!buffer_hz) {
+ read_psched();
+ }
+ return ((unsigned long long int) ticks_per_s * size) / rate;
+}
+
+/* Returns the number of bytes that need to be reserved for qdisc buffering at
+ * a transmission rate of 'rate' bytes per second. */
+static unsigned int
+tc_buffer_per_jiffy(unsigned int rate)
+{
+ if (!buffer_hz) {
+ read_psched();
+ }
+ return rate / buffer_hz;
+}
+
+/* Given Netlink 'msg' that describes a qdisc, extracts the name of the qdisc,
+ * e.g. "htb", into '*kind' (if it is nonnull). If 'options' is nonnull,
+ * extracts 'msg''s TCA_OPTIONS attributes into '*options' if it is present or
+ * stores NULL into it if it is absent.
+ *
+ * '*kind' and '*options' point into 'msg', so they are owned by whoever owns
+ * 'msg'.
+ *
+ * Returns 0 if successful, otherwise a positive errno value. */
+static int
+tc_parse_qdisc(const struct ofpbuf *msg, const char **kind,
+ struct nlattr **options)
+{
+ static const struct nl_policy tca_policy[] = {
+ [TCA_KIND] = { .type = NL_A_STRING, .optional = false },
+ [TCA_OPTIONS] = { .type = NL_A_NESTED, .optional = true },
+ };
+ struct nlattr *ta[ARRAY_SIZE(tca_policy)];
+
+ if (!nl_policy_parse(msg, NLMSG_HDRLEN + sizeof(struct tcmsg),
+ tca_policy, ta, ARRAY_SIZE(ta))) {
+ VLOG_WARN_RL(&rl, "failed to parse qdisc message");
+ goto error;
+ }
+
+ if (kind) {
+ *kind = nl_attr_get_string(ta[TCA_KIND]);
+ }
+
+ if (options) {
+ *options = ta[TCA_OPTIONS];
+ }
+
+ return 0;
+
+error:
+ if (kind) {
+ *kind = NULL;
+ }
+ if (options) {
+ *options = NULL;
+ }
+ return EPROTO;
+}
+
+/* Given Netlink 'msg' that describes a class, extracts the queue ID (e.g. the
+ * minor number of its class ID) into '*queue_id', its TCA_OPTIONS attribute
+ * into '*options', and its queue statistics into '*stats'. Any of the output
+ * arguments may be null.
+ *
+ * Returns 0 if successful, otherwise a positive errno value. */
+static int
+tc_parse_class(const struct ofpbuf *msg, unsigned int *handlep,
+ struct nlattr **options, struct netdev_queue_stats *stats)
+{
+ static const struct nl_policy tca_policy[] = {
+ [TCA_OPTIONS] = { .type = NL_A_NESTED, .optional = false },
+ [TCA_STATS2] = { .type = NL_A_NESTED, .optional = false },
+ };
+ struct nlattr *ta[ARRAY_SIZE(tca_policy)];
+
+ if (!nl_policy_parse(msg, NLMSG_HDRLEN + sizeof(struct tcmsg),
+ tca_policy, ta, ARRAY_SIZE(ta))) {
+ VLOG_WARN_RL(&rl, "failed to parse class message");
+ goto error;
+ }
+
+ if (handlep) {
+ struct tcmsg *tc = ofpbuf_at_assert(msg, NLMSG_HDRLEN, sizeof *tc);
+ *handlep = tc->tcm_handle;
+ }
+
+ if (options) {
+ *options = ta[TCA_OPTIONS];
+ }
+
+ if (stats) {
+ const struct gnet_stats_queue *gsq;
+ struct gnet_stats_basic gsb;
+
+ static const struct nl_policy stats_policy[] = {
+ [TCA_STATS_BASIC] = { .type = NL_A_UNSPEC, .optional = false,
+ .min_len = sizeof gsb },
+ [TCA_STATS_QUEUE] = { .type = NL_A_UNSPEC, .optional = false,
+ .min_len = sizeof *gsq },
+ };
+ struct nlattr *sa[ARRAY_SIZE(stats_policy)];
+
+ if (!nl_parse_nested(ta[TCA_STATS2], stats_policy,
+ sa, ARRAY_SIZE(sa))) {
+ VLOG_WARN_RL(&rl, "failed to parse class stats");
+ goto error;
+ }
+
+ /* Alignment issues screw up the length of struct gnet_stats_basic on
+ * some arch/bitsize combinations. Newer versions of Linux have a
+ * struct gnet_stats_basic_packed, but we can't depend on that. The
+ * easiest thing to do is just to make a copy. */
+ memset(&gsb, 0, sizeof gsb);
+ memcpy(&gsb, nl_attr_get(sa[TCA_STATS_BASIC]),
+ MIN(nl_attr_get_size(sa[TCA_STATS_BASIC]), sizeof gsb));
+ stats->tx_bytes = gsb.bytes;
+ stats->tx_packets = gsb.packets;
+
+ gsq = nl_attr_get(sa[TCA_STATS_QUEUE]);
+ stats->tx_errors = gsq->drops;
+ }
+
+ return 0;
+
+error:
+ if (options) {
+ *options = NULL;
+ }
+ if (stats) {
+ memset(stats, 0, sizeof *stats);
+ }
+ return EPROTO;
+}
+
+/* Queries the kernel for class with identifier 'handle' and parent 'parent'
+ * on 'netdev'. */
+static int
+tc_query_class(const struct netdev *netdev,
+ unsigned int handle, unsigned int parent,
+ struct ofpbuf **replyp)
+{
+ struct ofpbuf request;
+ struct tcmsg *tcmsg;
+ int error;
+
+ tcmsg = tc_make_request(netdev, RTM_GETTCLASS, NLM_F_ECHO, &request);
+ tcmsg->tcm_handle = handle;
+ tcmsg->tcm_parent = parent;
+
+ error = tc_transact(&request, replyp);
+ if (error) {
+ VLOG_WARN_RL(&rl, "query %s class %u:%u (parent %u:%u) failed (%s)",
+ netdev_get_name(netdev),
+ tc_get_major(handle), tc_get_minor(handle),
+ tc_get_major(parent), tc_get_minor(parent),
+ strerror(error));
+ }
+ return error;
+}
+
+/* Equivalent to "tc class del dev <name> handle <handle>". */
+static int
+tc_delete_class(const struct netdev *netdev, unsigned int handle)
+{
+ struct ofpbuf request;
+ struct tcmsg *tcmsg;
+ int error;
+
+ tcmsg = tc_make_request(netdev, RTM_DELTCLASS, 0, &request);
+ tcmsg->tcm_handle = handle;
+ tcmsg->tcm_parent = 0;
+
+ error = tc_transact(&request, NULL);
+ if (error) {
+ VLOG_WARN_RL(&rl, "delete %s class %u:%u failed (%s)",
+ netdev_get_name(netdev),
+ tc_get_major(handle), tc_get_minor(handle),
+ strerror(error));
+ }
+ return error;
+}
+
+/* Equivalent to "tc qdisc del dev <name> root". */
+static int
+tc_del_qdisc(struct netdev *netdev)
+{
+ struct netdev_dev_linux *netdev_dev =
+ netdev_dev_linux_cast(netdev_get_dev(netdev));
+ struct ofpbuf request;
+ struct tcmsg *tcmsg;
+ int error;
+
+ tcmsg = tc_make_request(netdev, RTM_DELQDISC, 0, &request);
+ tcmsg->tcm_handle = tc_make_handle(1, 0);
+ tcmsg->tcm_parent = TC_H_ROOT;
+
+ error = tc_transact(&request, NULL);
+ if (error == EINVAL) {
+ /* EINVAL probably means that the default qdisc was in use, in which
+ * case we've accomplished our purpose. */
+ error = 0;
+ }
+ if (!error && netdev_dev->tc) {
+ if (netdev_dev->tc->ops->tc_destroy) {
+ netdev_dev->tc->ops->tc_destroy(netdev_dev->tc);
+ }
+ netdev_dev->tc = NULL;
+ }
+ return error;
+}
+
+/* If 'netdev''s qdisc type and parameters are not yet known, queries the
+ * kernel to determine what they are. Returns 0 if successful, otherwise a
+ * positive errno value. */
+static int
+tc_query_qdisc(const struct netdev *netdev)
+{
+ struct netdev_dev_linux *netdev_dev =
+ netdev_dev_linux_cast(netdev_get_dev(netdev));
+ struct ofpbuf request, *qdisc;
+ const struct tc_ops *ops;
+ struct tcmsg *tcmsg;
+ int load_error;
+ int error;
+
+ if (netdev_dev->tc) {
+ return 0;
+ }
+
+ /* This RTM_GETQDISC is crafted to avoid OOPSing kernels that do not have
+ * commit 53b0f08 "net_sched: Fix qdisc_notify()", which is anything before
+ * 2.6.35 without that fix backported to it.
+ *
+ * To avoid the OOPS, we must not make a request that would attempt to dump
+ * a "built-in" qdisc, that is, the default pfifo_fast qdisc or one of a
+ * few others. There are a few ways that I can see to do this, but most of
+ * them seem to be racy (and if you lose the race the kernel OOPSes). The
+ * technique chosen here is to assume that any non-default qdisc that we
+ * create will have a class with handle 1:0. The built-in qdiscs only have
+ * a class with handle 0:0.
+ *
+ * We could check for Linux 2.6.35+ and use a more straightforward method
+ * there. */
+ tcmsg = tc_make_request(netdev, RTM_GETQDISC, NLM_F_ECHO, &request);
+ tcmsg->tcm_handle = tc_make_handle(1, 0);
+ tcmsg->tcm_parent = 0;
+
+ /* Figure out what tc class to instantiate. */
+ error = tc_transact(&request, &qdisc);
+ if (!error) {
+ const char *kind;
+
+ error = tc_parse_qdisc(qdisc, &kind, NULL);
+ if (error) {
+ ops = &tc_ops_other;
+ } else {
+ ops = tc_lookup_linux_name(kind);
+ if (!ops) {
+ static struct vlog_rate_limit rl2 = VLOG_RATE_LIMIT_INIT(1, 1);
+ VLOG_INFO_RL(&rl2, "unknown qdisc \"%s\"", kind);
+
+ ops = &tc_ops_other;
+ }
+ }
+ } else if (error == ENOENT) {
+ /* Either it's a built-in qdisc, or it's a qdisc set up by some
+ * other entity that doesn't have a handle 1:0. We will assume
+ * that it's the system default qdisc. */
+ ops = &tc_ops_default;
+ error = 0;
+ } else {
+ /* Who knows? Maybe the device got deleted. */
+ VLOG_WARN_RL(&rl, "query %s qdisc failed (%s)",
+ netdev_get_name(netdev), strerror(error));
+ ops = &tc_ops_other;
+ }
+
+ /* Instantiate it. */
+ load_error = ops->tc_load((struct netdev *) netdev, qdisc);
+ assert((load_error == 0) == (netdev_dev->tc != NULL));
+ ofpbuf_delete(qdisc);
+
+ return error ? error : load_error;
+}
+
+/* Linux traffic control uses tables with 256 entries ("rtab" tables) to
+ approximate the time to transmit packets of various lengths. For an MTU of
+ 256 or less, each entry is exact; for an MTU of 257 through 512, each entry
+ represents two possible packet lengths; for a MTU of 513 through 1024, four
+ possible lengths; and so on.
+
+ Returns, for the specified 'mtu', the number of bits that packet lengths
+ need to be shifted right to fit within such a 256-entry table. */
+static int
+tc_calc_cell_log(unsigned int mtu)
+{
+ int cell_log;
+
+ if (!mtu) {
+ mtu = ETH_PAYLOAD_MAX;
+ }
+ mtu += ETH_HEADER_LEN + VLAN_HEADER_LEN;
+
+ for (cell_log = 0; mtu >= 256; cell_log++) {
+ mtu >>= 1;
+ }
+
+ return cell_log;
+}
+
+/* Initializes 'rate' properly for a rate of 'Bps' bytes per second with an MTU
+ * of 'mtu'. */
+static void
+tc_fill_rate(struct tc_ratespec *rate, uint64_t Bps, int mtu)
+{
+ memset(rate, 0, sizeof *rate);
+ rate->cell_log = tc_calc_cell_log(mtu);
+ /* rate->overhead = 0; */ /* New in 2.6.24, not yet in some */
+ /* rate->cell_align = 0; */ /* distro headers. */
+ rate->mpu = ETH_TOTAL_MIN;
+ rate->rate = Bps;
+}
+
+/* Appends to 'msg' an "rtab" table for the specified 'rate' as a Netlink
+ * attribute of the specified "type".
+ *
+ * See tc_calc_cell_log() above for a description of "rtab"s. */
+static void
+tc_put_rtab(struct ofpbuf *msg, uint16_t type, const struct tc_ratespec *rate)
+{
+ uint32_t *rtab;
+ unsigned int i;
+
+ rtab = nl_msg_put_unspec_uninit(msg, type, TC_RTAB_SIZE);
+ for (i = 0; i < TC_RTAB_SIZE / sizeof *rtab; i++) {
+ unsigned packet_size = (i + 1) << rate->cell_log;
+ if (packet_size < rate->mpu) {
+ packet_size = rate->mpu;
+ }
+ rtab[i] = tc_bytes_to_ticks(rate->rate, packet_size);
+ }
+}
+
+/* Calculates the proper value of 'buffer' or 'cbuffer' in HTB options given a
+ * rate of 'Bps' bytes per second, the specified 'mtu', and a user-requested
+ * burst size of 'burst_bytes'. (If no value was requested, a 'burst_bytes' of
+ * 0 is fine.)
+ *
+ * This */
+static int
+tc_calc_buffer(unsigned int Bps, int mtu, uint64_t burst_bytes)
+{
+ unsigned int min_burst = tc_buffer_per_jiffy(Bps) + mtu;
+ return tc_bytes_to_ticks(Bps, MAX(burst_bytes, min_burst));
+}
+
+\f
+/* Utility functions. */
+
+static int
+get_stats_via_netlink(int ifindex, struct netdev_stats *stats)
+{
+ /* Policy for RTNLGRP_LINK messages.
+ *
+ * There are *many* more fields in these messages, but currently we only
+ * care about these fields. */
+ static const struct nl_policy rtnlgrp_link_policy[] = {
+ [IFLA_IFNAME] = { .type = NL_A_STRING, .optional = false },
+ [IFLA_STATS] = { .type = NL_A_UNSPEC, .optional = true,
+ .min_len = sizeof(struct rtnl_link_stats) },
+ };
+
+ struct ofpbuf request;
+ struct ofpbuf *reply;
+ struct ifinfomsg *ifi;
+ const struct rtnl_link_stats *rtnl_stats;
+ struct nlattr *attrs[ARRAY_SIZE(rtnlgrp_link_policy)];
+ int error;
+
+ ofpbuf_init(&request, 0);
+ nl_msg_put_nlmsghdr(&request, sizeof *ifi, RTM_GETLINK, NLM_F_REQUEST);
+ ifi = ofpbuf_put_zeros(&request, sizeof *ifi);
+ ifi->ifi_family = PF_UNSPEC;
+ ifi->ifi_index = ifindex;
+ error = nl_sock_transact(rtnl_sock, &request, &reply);
+ ofpbuf_uninit(&request);
+ if (error) {
+ return error;
+ }
+
+ if (!nl_policy_parse(reply, NLMSG_HDRLEN + sizeof(struct ifinfomsg),
+ rtnlgrp_link_policy,
+ attrs, ARRAY_SIZE(rtnlgrp_link_policy))) {
+ ofpbuf_delete(reply);
+ return EPROTO;
+ }
+
+ if (!attrs[IFLA_STATS]) {
+ VLOG_WARN_RL(&rl, "RTM_GETLINK reply lacks stats");
+ ofpbuf_delete(reply);
+ return EPROTO;
+ }
+
+ rtnl_stats = nl_attr_get(attrs[IFLA_STATS]);
+ stats->rx_packets = rtnl_stats->rx_packets;
+ stats->tx_packets = rtnl_stats->tx_packets;
+ stats->rx_bytes = rtnl_stats->rx_bytes;
+ stats->tx_bytes = rtnl_stats->tx_bytes;
+ stats->rx_errors = rtnl_stats->rx_errors;
+ stats->tx_errors = rtnl_stats->tx_errors;
+ stats->rx_dropped = rtnl_stats->rx_dropped;