/*
 * net/ife/ife.c - Inter-FE protocol based on ForCES WG InterFE LFB
 * Copyright (c) 2015 Jamal Hadi Salim <jhs@mojatatu.com>
 * Copyright (c) 2017 Yotam Gigi <yotamg@mellanox.com>
 *
 * Refer to: draft-ietf-forces-interfelfb-03 and netdev01 paper:
 * "Distributing Linux Traffic Control Classifier-Action Subsystem"
 * Authors: Jamal Hadi Salim and Damascene M. Joachimpillai
 *
 * 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.
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
#include <net/net_namespace.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <linux/etherdevice.h>
#include <net/ife.h>

struct ifeheadr {
	__be16 metalen;
	u8 tlv_data[];
};

void *ife_encode(struct sk_buff *skb, u16 metalen)
{
	/* OUTERHDR:TOTMETALEN:{TLVHDR:Metadatum:TLVHDR..}:ORIGDATA
	 * where ORIGDATA = original ethernet header ...
	 */
	int hdrm = metalen + IFE_METAHDRLEN;
	int total_push = hdrm + skb->dev->hard_header_len;
	struct ifeheadr *ifehdr;
	struct ethhdr *iethh;	/* inner ether header */
	int skboff = 0;
	int err;

	err = skb_cow_head(skb, total_push);
	if (unlikely(err))
		return NULL;

	iethh = (struct ethhdr *) skb->data;

	__skb_push(skb, total_push);
	memcpy(skb->data, iethh, skb->dev->hard_header_len);
	skb_reset_mac_header(skb);
	skboff += skb->dev->hard_header_len;

	/* total metadata length */
	ifehdr = (struct ifeheadr *) (skb->data + skboff);
	metalen += IFE_METAHDRLEN;
	ifehdr->metalen = htons(metalen);

	return ifehdr->tlv_data;
}
EXPORT_SYMBOL_GPL(ife_encode);

void *ife_decode(struct sk_buff *skb, u16 *metalen)
{
	struct ifeheadr *ifehdr;
	int total_pull;
	u16 ifehdrln;

	ifehdr = (struct ifeheadr *) (skb->data + skb->dev->hard_header_len);
	ifehdrln = ntohs(ifehdr->metalen);
	total_pull = skb->dev->hard_header_len + ifehdrln;

	if (unlikely(ifehdrln < 2))
		return NULL;

	if (unlikely(!pskb_may_pull(skb, total_pull)))
		return NULL;

	skb_set_mac_header(skb, total_pull);
	__skb_pull(skb, total_pull);
	*metalen = ifehdrln - IFE_METAHDRLEN;

	return &ifehdr->tlv_data;
}
EXPORT_SYMBOL_GPL(ife_decode);

struct meta_tlvhdr {
	__be16 type;
	__be16 len;
};

/* Caller takes care of presenting data in network order
 */
void *ife_tlv_meta_decode(void *skbdata, u16 *attrtype, u16 *dlen, u16 *totlen)
{
	struct meta_tlvhdr *tlv = (struct meta_tlvhdr *) skbdata;

	*dlen = ntohs(tlv->len) - NLA_HDRLEN;
	*attrtype = ntohs(tlv->type);

	if (totlen)
		*totlen = nla_total_size(*dlen);

	return skbdata + sizeof(struct meta_tlvhdr);
}
EXPORT_SYMBOL_GPL(ife_tlv_meta_decode);

void *ife_tlv_meta_next(void *skbdata)
{
	struct meta_tlvhdr *tlv = (struct meta_tlvhdr *) skbdata;
	u16 tlvlen = ntohs(tlv->len);

	tlvlen = NLA_ALIGN(tlvlen);

	return skbdata + tlvlen;
}
EXPORT_SYMBOL_GPL(ife_tlv_meta_next);

/* Caller takes care of presenting data in network order
 */
int ife_tlv_meta_encode(void *skbdata, u16 attrtype, u16 dlen, const void *dval)
{
	__be32 *tlv = (__be32 *) (skbdata);
	u16 totlen = nla_total_size(dlen);	/*alignment + hdr */
	char *dptr = (char *) tlv + NLA_HDRLEN;
	u32 htlv = attrtype << 16 | (dlen + NLA_HDRLEN);

	*tlv = htonl(htlv);
	memset(dptr, 0, totlen - NLA_HDRLEN);
	memcpy(dptr, dval, dlen);

	return totlen;
}
EXPORT_SYMBOL_GPL(ife_tlv_meta_encode);

MODULE_AUTHOR("Jamal Hadi Salim <jhs@mojatatu.com>");
MODULE_AUTHOR("Yotam Gigi <yotamg@mellanox.com>");
MODULE_DESCRIPTION("Inter-FE LFB action");
MODULE_LICENSE("GPL");
option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;</td><td class='right'>2017-02-03 14:18:39 -0800</td></tr>
<tr><th>committer</th><td>Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;</td><td class='right'>2017-02-04 00:11:08 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/tipc/udp_media.h?id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>6e978b22efa1db9f6e71b24440b5f1d93e968ee3</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/tipc/udp_media.h?id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>c666f7a26b860674848949e39a610222b0723f89</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/tipc/udp_media.h?id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>net/tipc/udp_media.h</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/tipc/udp_media.h?id=3c223c19aea85d3dda1416c187915f4a30b04b1f'>3c223c19aea85d3dda1416c187915f4a30b04b1f</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/tipc/udp_media.h?id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3&amp;id2=3c223c19aea85d3dda1416c187915f4a30b04b1f'>diff</a>)</td></tr></table>
<div class='commit-subject'>cpufreq: intel_pstate: Disable energy efficiency optimization</div><div class='commit-msg'>Some Kabylake desktop processors may not reach max turbo when running in
HWP mode, even if running under sustained 100% utilization.

This occurs when the HWP.EPP (Energy Performance Preference) is set to
"balance_power" (0x80) -- the default on most systems.

It occurs because the platform BIOS may erroneously enable an
energy-efficiency setting -- MSR_IA32_POWER_CTL BIT-EE, which is not
recommended to be enabled on this SKU.

On the failing systems, this BIOS issue was not discovered when the
desktop motherboard was tested with Windows, because the BIOS also
neglects to provide the ACPI/CPPC table, that Windows requires to enable
HWP, and so Windows runs in legacy P-state mode, where this setting has
no effect.

Linux' intel_pstate driver does not require ACPI/CPPC to enable HWP, and
so it runs in HWP mode, exposing this incorrect BIOS configuration.

There are several ways to address this problem.

First, Linux can also run in legacy P-state mode on this system.
As intel_pstate is how Linux enables HWP, booting with
"intel_pstate=disable"
will run in acpi-cpufreq/ondemand legacy p-state mode.

Or second, the "performance" governor can be used with intel_pstate,
which will modify HWP.EPP to 0.

Or third, starting in 4.10, the
/sys/devices/system/cpu/cpufreq/policy*/energy_performance_preference
attribute in can be updated from "balance_power" to "performance".

Or fourth, apply this patch, which fixes the erroneous setting of
MSR_IA32_POWER_CTL BIT_EE on this model, allowing the default
configuration to function as designed.

Signed-off-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Reviewed-by: Len Brown &lt;len.brown@intel.com&gt;
Cc: 4.6+ &lt;stable@vger.kernel.org&gt; # 4.6+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>Diffstat</a> (limited to 'net/tipc/udp_media.h')</div><table summary='diffstat' class='diffstat'>