Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking changes from David Miller:

 1) Get rid of the error prone NLA_PUT*() macros that used an embedded
    goto.

 2) Kill off the token-ring and MCA networking drivers, from Paul
    Gortmaker.

 3) Reduce high-order allocations made by datagram AF_UNIX sockets, from
    Eric Dumazet.

 4) Add PTP hardware clock support to IGB and IXGBE, from Richard
    Cochran and Jacob Keller.

 5) Allow users to query timestamping capabilities of a card via
    ethtool, from Richard Cochran.

 6) Add loadbalance mode to the teaming driver, from Jiri Pirko.  Part
    of this is that we can now have BPF filters not attached to sockets,
    and the loadbalancing function is calculated using one.

 7) Francois Romieu went through the network drivers removing gratuitous
    uses of netdev->base_addr, perhaps some day we can remove it
    completely but it's used for ISA probing still.

 8) Add a BPF JIT for sparc.  I know, who cares, right? :-)

 9) Move networking sysctl registry away from using the compatability
    mode interfaces in the sysctl code.  From Eric W Biederman.

10) Pavel Emelyanov added a way to save and restore TCP socket state via
    TCP_REPAIR, TCP_REPAIR_QUEUE, and TCP_QUEUE_SEQ socket options as
    well as a way to forcefully bind a socket to a port via the
    sk->sk_reuse value SK_FORCE_REUSE.  There is also a
    TCP_REPAIR_OPTIONS which allows to reinstante the TCP options
    enabled on the connection.

11) Several enhancements from Eric Dumazet that, in particular, can
    enhance splice performance on TCP sockets significantly.

     a) Reset the offset of the per-socket sendmsg page when we know
        we're the only use of the page in linear_to_page().

     b) Add facilities such that skb->data can be backed a page rather
        than SLAB kmalloc'd memory.  In particular devices which were
        receiving into linear RX buffers can now end up providing paged
        data.

    The big result is that code like splice and GRO do not have to copy
    any more.

12) Allow a pure sender to more gracefully handle ACK backlogs in TCP.
    What can happen at high rates is that the sender hasn't grown his
    receive buffer limits at all (he's not receiving data so really
    doesn't need to), but the non-data ACKs consume receive buffer
    space.

    sk_add_backlog() is too aggressive in dropping frames in this case,
    so relax it's requirements by using the receive buffer plus the send
    buffer limit as the backlog limit instead of just the former.

    Also from Eric Dumazet.

13) Add ipv6 support to L2TP, from Benjamin LaHaise, James Chapman, and
    Chris Elston.

14) Implement TCP early retransmit (RFC 5827), from Yuchung Cheng.
    Basically, we can start fast retransmit before hiting the dupack
    threshold under certain conditions.

15) New CODEL active queue management packet scheduler, from Eric
    Dumazet based upon initial work by Dave Taht.

    Basically, the big feature is that packets are dropped (or ECN bits
    are set) based upon how long packets live in the queue, rather than
    the queue length (which is what RED uses).

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1341 commits)
  drivers/net/stmmac: seq_file fix memory leak
  ipv6/exthdrs: strict Pad1 and PadN check
  USB: qmi_wwan: Add ZTE (Vodafone) K3520-Z
  USB: qmi_wwan: Add ZTE (Vodafone) K3765-Z
  USB: qmi_wwan: Make forced int 4 whitelist generic
  net/ipv4: replace simple_strtoul with kstrtoul
  net/ipv4/ipconfig: neaten __setup placement
  net: qmi_wwan: Add Vodafone/Huawei K5005 support
  net: cdc_ether: Add ZTE WWAN matches before generic Ethernet
  ipv6: use skb coalescing in reassembly
  ipv4: use skb coalescing in defragmentation
  net: introduce skb_try_coalesce()
  net:ipv6:fixed space issues relating to operators.
  net:ipv6:fixed a trailing white space issue.
  ipv6: disable GSO on sockets hitting dst_allfrag
  tg3: use netdev_alloc_frag() API
  net: napi_frags_skb() is static
  ppp: avoid false drop_monitor false positives
  ipv6: bool/const conversions phase2
  ipx: Remove spurious NULL checking in ipx_ioctl().
  ...

1 files changed, 342 insertions, 0 deletions

diff --git a/include/net/codel.h b/include/net/codel.h
new file mode 100644
index 000000000000..550debfc2403
--- /dev/null
+++ b/include/net/codel.h
@@ -0,0 +1,342 @@
+#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 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>
+#include <net/pkt_sched.h>
+#include <net/inet_ecn.h>
+#include <linux/reciprocal_div.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_to_ns(ktime_get());
+
+	return ns >> CODEL_SHIFT;
+}
+
+#define codel_time_after(a, b)		((s32)(a) - (s32)(b) > 0)
+#define codel_time_after_eq(a, b)	((s32)(a) - (s32)(b) >= 0)
+#define codel_time_before(a, b)		((s32)(a) - (s32)(b) < 0)
+#define codel_time_before_eq(a, b)	((s32)(a) - (s32)(b) <= 0)
+
+/* Qdiscs using codel plugin must use codel_skb_cb in their own cb[] */
+struct codel_skb_cb {
+	codel_time_t enqueue_time;
+};
+
+static struct codel_skb_cb *get_codel_cb(const struct sk_buff *skb)
+{
+	qdisc_cb_private_validate(skb, sizeof(struct codel_skb_cb));
+	return (struct codel_skb_cb *)qdisc_skb_cb(skb)->data;
+}
+
+static codel_time_t codel_get_enqueue_time(const struct sk_buff *skb)
+{
+	return get_codel_cb(skb)->enqueue_time;
+}
+
+static void codel_set_enqueue_time(struct sk_buff *skb)
+{
+	get_codel_cb(skb)->enqueue_time = codel_get_time();
+}
+
+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)
+ * @interval:	width of moving time window
+ * @ecn:	is Explicit Congestion Notification enabled
+ */
+struct codel_params {
+	codel_time_t	target;
+	codel_time_t	interval;
+	bool		ecn;
+};
+
+/**
+ * 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()
+ * ecn_mark:	number of packets we ECN marked instead of dropping
+ */
+struct codel_stats {
+	u32		maxpacket;
+	u32		drop_count;
+	u32		ecn_mark;
+};
+
+static void codel_params_init(struct codel_params *params)
+{
+	params->interval = MS2TIME(100);
+	params->target = MS2TIME(5);
+	params->ecn = false;
+}
+
+static void codel_vars_init(struct codel_vars *vars)
+{
+	memset(vars, 0, sizeof(*vars));
+}
+
+static void codel_stats_init(struct codel_stats *stats)
+{
+	stats->maxpacket = 256;
+}
+
+/*
+ * http://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Iterative_methods_for_reciprocal_square_roots
+ * new_invsqrt = (invsqrt / 2) * (3 - count * invsqrt^2)
+ *
+ * Here, invsqrt is a fixed point number (< 1.0), 32bit mantissa, aka Q0.32
+ */
+static void codel_Newton_step(struct codel_vars *vars)
+{
+	u32 invsqrt = ((u32)vars->rec_inv_sqrt) << REC_INV_SQRT_SHIFT;
+	u32 invsqrt2 = ((u64)invsqrt * invsqrt) >> 32;
+	u64 val = (3LL << 32) - ((u64)vars->count * invsqrt2);
+
+	val >>= 2; /* avoid overflow in following multiply */
+	val = (val * invsqrt) >> (32 - 2 + 1);
+
+	vars->rec_inv_sqrt = val >> REC_INV_SQRT_SHIFT;
+}
+
+/*
+ * CoDel control_law is t + interval/sqrt(count)
+ * We maintain in rec_inv_sqrt the reciprocal value of sqrt(count) to avoid
+ * both sqrt() and divide operation.
+ */
+static codel_time_t codel_control_law(codel_time_t t,
+				      codel_time_t interval,
+				      u32 rec_inv_sqrt)
+{
+	return t + reciprocal_divide(interval, rec_inv_sqrt << REC_INV_SQRT_SHIFT);
+}
+
+
+static bool codel_should_drop(const struct sk_buff *skb,
+			      struct Qdisc *sch,
+			      struct codel_vars *vars,
+			      struct codel_params *params,
+			      struct codel_stats *stats,
+			      codel_time_t now)
+{
+	bool ok_to_drop;
+
+	if (!skb) {
+		vars->first_above_time = 0;
+		return false;
+	}
+
+	vars->ldelay = now - codel_get_enqueue_time(skb);
+	sch->qstats.backlog -= qdisc_pkt_len(skb);
+
+	if (unlikely(qdisc_pkt_len(skb) > stats->maxpacket))
+		stats->maxpacket = qdisc_pkt_len(skb);
+
+	if (codel_time_before(vars->ldelay, params->target) ||
+	    sch->qstats.backlog <= stats->maxpacket) {
+		/* went below - stay below for at least interval */
+		vars->first_above_time = 0;
+		return false;
+	}
+	ok_to_drop = false;
+	if (vars->first_above_time == 0) {
+		/* just went above from below. If we stay above
+		 * for at least interval we'll say it's ok to drop
+		 */
+		vars->first_above_time = now + params->interval;
+	} else if (codel_time_after(now, vars->first_above_time)) {
+		ok_to_drop = true;
+	}
+	return ok_to_drop;
+}
+
+typedef struct sk_buff * (*codel_skb_dequeue_t)(struct codel_vars *vars,
+						struct Qdisc *sch);
+
+static struct sk_buff *codel_dequeue(struct Qdisc *sch,
+				     struct codel_params *params,
+				     struct codel_vars *vars,
+				     struct codel_stats *stats,
+				     codel_skb_dequeue_t dequeue_func)
+{
+	struct sk_buff *skb = dequeue_func(vars, sch);
+	codel_time_t now;
+	bool drop;
+
+	if (!skb) {
+		vars->dropping = false;
+		return skb;
+	}
+	now = codel_get_time();
+	drop = codel_should_drop(skb, sch, vars, params, stats, now);
+	if (vars->dropping) {
+		if (!drop) {
+			/* sojourn time below target - leave dropping state */
+			vars->dropping = false;
+		} else if (codel_time_after_eq(now, vars->drop_next)) {
+			/* It's time for the next drop. Drop the current
+			 * packet and dequeue the next. The dequeue might
+			 * take us out of dropping state.
+			 * If not, schedule the next drop.
+			 * A large backlog might result in drop rates so high
+			 * that the next drop should happen now,
+			 * hence the while loop.
+			 */
+			while (vars->dropping &&
+			       codel_time_after_eq(now, vars->drop_next)) {
+				vars->count++; /* dont care of possible wrap
+						* since there is no more divide
+						*/
+				codel_Newton_step(vars);
+				if (params->ecn && INET_ECN_set_ce(skb)) {
+					stats->ecn_mark++;
+					vars->drop_next =
+						codel_control_law(vars->drop_next,
+								  params->interval,
+								  vars->rec_inv_sqrt);
+					goto end;
+				}
+				qdisc_drop(skb, sch);
+				stats->drop_count++;
+				skb = dequeue_func(vars, sch);
+				if (!codel_should_drop(skb, sch,
+						       vars, params, stats, now)) {
+					/* leave dropping state */
+					vars->dropping = false;
+				} else {
+					/* and schedule the next drop */
+					vars->drop_next =
+						codel_control_law(vars->drop_next,
+								  params->interval,
+								  vars->rec_inv_sqrt);
+				}
+			}
+		}
+	} else if (drop) {
+		if (params->ecn && INET_ECN_set_ce(skb)) {
+			stats->ecn_mark++;
+		} else {
+			qdisc_drop(skb, sch);
+			stats->drop_count++;
+
+			skb = dequeue_func(vars, sch);
+			drop = codel_should_drop(skb, sch, vars, params,
+						 stats, now);
+		}
+		vars->dropping = true;
+		/* if min went above target close to when we last went below it
+		 * assume that the drop rate that controlled the queue on the
+		 * last cycle is a good starting point to control it now.
+		 */
+		if (codel_time_before(now - vars->drop_next,
+				      16 * params->interval)) {
+			vars->count = (vars->count - vars->lastcount) | 1;
+			/* we dont care if rec_inv_sqrt approximation
+			 * is not very precise :
+			 * Next Newton steps will correct it quadratically.
+			 */
+			codel_Newton_step(vars);
+		} else {
+			vars->count = 1;
+			vars->rec_inv_sqrt = ~0U >> REC_INV_SQRT_SHIFT;
+		}
+		vars->lastcount = vars->count;
+		vars->drop_next = codel_control_law(now, params->interval,
+						    vars->rec_inv_sqrt);
+	}
+end:
+	return skb;
+}
+#endif