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diff --git a/include/net/codel.h b/include/net/codel.h
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+#ifndef __NET_SCHED_CODEL_H
+#define __NET_SCHED_CODEL_H
+
+/*
+ * Codel - The Controlled-Delay Active Queue Management algorithm
+ *
+ * Copyright (C) 2011-2012 Kathleen Nichols <nichols@pollere.com>
+ * Copyright (C) 2011-2012 Van Jacobson <van@pollere.net>
+ * Copyright (C) 2012 Michael D. Taht <dave.taht@bufferbloat.net>
+ * Copyright (C) 2012,2015 Eric Dumazet <edumazet@google.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions, and the following disclaimer,
+ * without modification.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The names of the authors may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/ktime.h>
+#include <linux/skbuff.h>
+
+/* Controlling Queue Delay (CoDel) algorithm
+ * =========================================
+ * Source : Kathleen Nichols and Van Jacobson
+ * http://queue.acm.org/detail.cfm?id=2209336
+ *
+ * Implemented on linux by Dave Taht and Eric Dumazet
+ */
+
+
+/* CoDel uses a 1024 nsec clock, encoded in u32
+ * This gives a range of 2199 seconds, because of signed compares
+ */
+typedef u32 codel_time_t;
+typedef s32 codel_tdiff_t;
+#define CODEL_SHIFT 10
+#define MS2TIME(a) ((a * NSEC_PER_MSEC) >> CODEL_SHIFT)
+
+static inline codel_time_t codel_get_time(void)
+{
+ u64 ns = ktime_get_ns();
+
+ return ns >> CODEL_SHIFT;
+}
+
+/* Dealing with timer wrapping, according to RFC 1982, as desc in wikipedia:
+ * https://en.wikipedia.org/wiki/Serial_number_arithmetic#General_Solution
+ * codel_time_after(a,b) returns true if the time a is after time b.
+ */
+#define codel_time_after(a, b) \
+ (typecheck(codel_time_t, a) && \
+ typecheck(codel_time_t, b) && \
+ ((s32)((a) - (b)) > 0))
+#define codel_time_before(a, b) codel_time_after(b, a)
+
+#define codel_time_after_eq(a, b) \
+ (typecheck(codel_time_t, a) && \
+ typecheck(codel_time_t, b) && \
+ ((s32)((a) - (b)) >= 0))
+#define codel_time_before_eq(a, b) codel_time_after_eq(b, a)
+
+static inline u32 codel_time_to_us(codel_time_t val)
+{
+ u64 valns = ((u64)val << CODEL_SHIFT);
+
+ do_div(valns, NSEC_PER_USEC);
+ return (u32)valns;
+}
+
+/**
+ * struct codel_params - contains codel parameters
+ * @target: target queue size (in time units)
+ * @ce_threshold: threshold for marking packets with ECN CE
+ * @interval: width of moving time window
+ * @mtu: device mtu, or minimal queue backlog in bytes.
+ * @ecn: is Explicit Congestion Notification enabled
+ * @ce_threshold_selector: apply ce_threshold to packets matching this value
+ * in the diffserv/ECN byte of the IP header
+ * @ce_threshold_mask: mask to apply to ce_threshold_selector comparison
+ */
+struct codel_params {
+ codel_time_t target;
+ codel_time_t ce_threshold;
+ codel_time_t interval;
+ u32 mtu;
+ bool ecn;
+ u8 ce_threshold_selector;
+ u8 ce_threshold_mask;
+};
+
+/**
+ * struct codel_vars - contains codel variables
+ * @count: how many drops we've done since the last time we
+ * entered dropping state
+ * @lastcount: count at entry to dropping state
+ * @dropping: set to true if in dropping state
+ * @rec_inv_sqrt: reciprocal value of sqrt(count) >> 1
+ * @first_above_time: when we went (or will go) continuously above target
+ * for interval
+ * @drop_next: time to drop next packet, or when we dropped last
+ * @ldelay: sojourn time of last dequeued packet
+ */
+struct codel_vars {
+ u32 count;
+ u32 lastcount;
+ bool dropping;
+ u16 rec_inv_sqrt;
+ codel_time_t first_above_time;
+ codel_time_t drop_next;
+ codel_time_t ldelay;
+};
+
+#define REC_INV_SQRT_BITS (8 * sizeof(u16)) /* or sizeof_in_bits(rec_inv_sqrt) */
+/* needed shift to get a Q0.32 number from rec_inv_sqrt */
+#define REC_INV_SQRT_SHIFT (32 - REC_INV_SQRT_BITS)
+
+/**
+ * struct codel_stats - contains codel shared variables and stats
+ * @maxpacket: largest packet we've seen so far
+ * @drop_count: temp count of dropped packets in dequeue()
+ * @drop_len: bytes of dropped packets in dequeue()
+ * ecn_mark: number of packets we ECN marked instead of dropping
+ * ce_mark: number of packets CE marked because sojourn time was above ce_threshold
+ */
+struct codel_stats {
+ u32 maxpacket;
+ u32 drop_count;
+ u32 drop_len;
+ u32 ecn_mark;
+ u32 ce_mark;
+};
+
+#define CODEL_DISABLED_THRESHOLD INT_MAX
+
+typedef u32 (*codel_skb_len_t)(const struct sk_buff *skb);
+typedef codel_time_t (*codel_skb_time_t)(const struct sk_buff *skb);
+typedef void (*codel_skb_drop_t)(struct sk_buff *skb, void *ctx);
+typedef struct sk_buff * (*codel_skb_dequeue_t)(struct codel_vars *vars,
+ void *ctx);
+
+#endif