/* -*- linux-c -*- ------------------------------------------------------- *
 *
 *   Copyright 2002 H. Peter Anvin - All Rights Reserved
 *
 *   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, Inc., 53 Temple Place Ste 330,
 *   Boston MA 02111-1307, USA; either version 2 of the License, or
 *   (at your option) any later version; incorporated herein by reference.
 *
 * ----------------------------------------------------------------------- */

/*
 * raid6/recov.c
 *
 * RAID-6 data recovery in dual failure mode.  In single failure mode,
 * use the RAID-5 algorithm (or, in the case of Q failure, just reconstruct
 * the syndrome.)
 */

#include <linux/export.h>
#include <linux/raid/pq.h>

/* Recover two failed data blocks. */
static void raid6_2data_recov_intx1(int disks, size_t bytes, int faila,
		int failb, void **ptrs)
{
	u8 *p, *q, *dp, *dq;
	u8 px, qx, db;
	const u8 *pbmul;	/* P multiplier table for B data */
	const u8 *qmul;		/* Q multiplier table (for both) */

	p = (u8 *)ptrs[disks-2];
	q = (u8 *)ptrs[disks-1];

	/* Compute syndrome with zero for the missing data pages
	   Use the dead data pages as temporary storage for
	   delta p and delta q */
	dp = (u8 *)ptrs[faila];
	ptrs[faila] = (void *)raid6_empty_zero_page;
	ptrs[disks-2] = dp;
	dq = (u8 *)ptrs[failb];
	ptrs[failb] = (void *)raid6_empty_zero_page;
	ptrs[disks-1] = dq;

	raid6_call.gen_syndrome(disks, bytes, ptrs);

	/* Restore pointer table */
	ptrs[faila]   = dp;
	ptrs[failb]   = dq;
	ptrs[disks-2] = p;
	ptrs[disks-1] = q;

	/* Now, pick the proper data tables */
	pbmul = raid6_gfmul[raid6_gfexi[failb-faila]];
	qmul  = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]];

	/* Now do it... */
	while ( bytes-- ) {
		px    = *p ^ *dp;
		qx    = qmul[*q ^ *dq];
		*dq++ = db = pbmul[px] ^ qx; /* Reconstructed B */
		*dp++ = db ^ px; /* Reconstructed A */
		p++; q++;
	}
}

/* Recover failure of one data block plus the P block */
static void raid6_datap_recov_intx1(int disks, size_t bytes, int faila,
		void **ptrs)
{
	u8 *p, *q, *dq;
	const u8 *qmul;		/* Q multiplier table */

	p = (u8 *)ptrs[disks-2];
	q = (u8 *)ptrs[disks-1];

	/* Compute syndrome with zero for the missing data page
	   Use the dead data page as temporary storage for delta q */
	dq = (u8 *)ptrs[faila];
	ptrs[faila] = (void *)raid6_empty_zero_page;
	ptrs[disks-1] = dq;

	raid6_call.gen_syndrome(disks, bytes, ptrs);

	/* Restore pointer table */
	ptrs[faila]   = dq;
	ptrs[disks-1] = q;

	/* Now, pick the proper data tables */
	qmul  = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]]];

	/* Now do it... */
	while ( bytes-- ) {
		*p++ ^= *dq = qmul[*q ^ *dq];
		q++; dq++;
	}
}


const struct raid6_recov_calls raid6_recov_intx1 = {
	.data2 = raid6_2data_recov_intx1,
	.datap = raid6_datap_recov_intx1,
	.valid = NULL,
	.name = "intx1",
	.priority = 0,
};

#ifndef __KERNEL__
/* Testing only */

/* Recover two failed blocks. */
void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, void **ptrs)
{
	if ( faila > failb ) {
		int tmp = faila;
		faila = failb;
		failb = tmp;
	}

	if ( failb == disks-1 ) {
		if ( faila == disks-2 ) {
			/* P+Q failure.  Just rebuild the syndrome. */
			raid6_call.gen_syndrome(disks, bytes, ptrs);
		} else {
			/* data+Q failure.  Reconstruct data from P,
			   then rebuild syndrome. */
			/* NOT IMPLEMENTED - equivalent to RAID-5 */
		}
	} else {
		if ( failb == disks-2 ) {
			/* data+P failure. */
			raid6_datap_recov(disks, bytes, faila, ptrs);
		} else {
			/* data+data failure. */
			raid6_2data_recov(disks, bytes, faila, failb, ptrs);
		}
	}
}

#endif
20266469979c9297debc05f60c'>net/act_pedit: Introduce 'add' operation</a></td><td>Amir Vadai</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+1</span></td></tr>
<tr class='nohover-highlight'><td/><td colspan='5' class='logmsg'>
This command could be useful to inc/dec fields.

For example, to forward any TCP packet and decrease its TTL:
$ tc filter add dev enp0s9 protocol ip parent ffff: \
    flower ip_proto tcp \
    action pedit munge ip ttl add 0xff pipe \
    action mirred egress redirect dev veth0

In the example above, adding 0xff to this u8 field is actually
decreasing it by one, since the operation is masked.

Signed-off-by: Amir Vadai &lt;amir@vadai.me&gt;
Reviewed-by: Or Gerlitz &lt;ogerlitz@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;


</td></tr>
<tr class='logheader'><td><span title='2017-02-10 13:18:33 -0500'>2017-02-10</span></td><td class='logsubject'><a href='/cgit.cgi/linux/net-next.git/commit/include/net/tc_act?id=71d0ed7079dffbc5cd0941d77d9b84e04109c9bb'>net/act_pedit: Support using offset relative to the conventional network headers</a></td><td>Amir Vadai</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+5</span></td></tr>
<tr class='nohover-highlight'><td/><td colspan='5' class='logmsg'>
Extend pedit to enable the user setting offset relative to network
headers. This change would enable to work with more complex header
schemes (vs the simple IPv4 case) where setting a fixed offset relative
to the network header is not enough.

After this patch, the action has information about the exact header type
and field inside this header. This information could be used later on
for hardware offloading of pedit.

Backward compatibility was being kept:
1. Old kernel &lt;-&gt; new userspace
2. New kernel &lt;-&gt; old userspace
3. add rule using new userspace &lt;-&gt; dump using old userspace
4. add rule using old userspace &lt;-&gt; dump using new userspace

When using the extended api, new netlink attributes are being used. This
way, operation will fail in (1) and (3) - and no malformed rule be added
or dumped. Of course, new user space that doesn't need the new
functionality can use the old netlink attributes and operation will
succeed.
Since action can support both api's, (2) should work, and it is easy to
write the new user space to have (4) work.

The action is having a strict check that only header types and commands
it can handle are accepted. This way future additions will be much
easier.

Usage example:
$ tc filter add dev enp0s9 protocol ip parent ffff: \
  flower \
    ip_proto tcp \
    dst_port 80 \
  action pedit munge tcp dport set 8080 pipe \
  action mirred egress redirect dev veth0

Will forward tcp port whose original dest port is 80, while modifying
the destination port to 8080.

Signed-off-by: Amir Vadai &lt;amir@vadai.me&gt;
Reviewed-by: Or Gerlitz &lt;ogerlitz@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;


</td></tr>
<tr class='logheader'><td><span title='2017-02-03 15:16:46 -0500'>2017-02-03</span></td><td class='logsubject'><a href='/cgit.cgi/linux/net-next.git/commit/include/net/tc_act?id=295a6e06d21e1f469c9f38b00125a13b60ad4e7c'>net/sched: act_ife: Change to use ife module</a></td><td>Yotam Gigi</td><td>1</td><td><span class='deletions'>-1</span>/<span class='insertions'>+0</span></td></tr>
<tr class='nohover-highlight'><td/><td colspan='5' class='logmsg'>
Use the encode/decode functionality from the ife module instead of using
implementation inside the act_ife.

Reviewed-by: Jiri Pirko &lt;jiri@mellanox.com&gt;
Signed-off-by: Yotam Gigi &lt;yotamg@mellanox.com&gt;
Signed-off-by: Jamal Hadi Salim &lt;jhs@mojatatu.com&gt;
Signed-off-by: Roman Mashak &lt;mrv@mojatatu.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;


</td></tr>
<tr class='logheader'><td><span title='2017-02-03 15:16:45 -0500'>2017-02-03</span></td><td class='logsubject'><a href='/cgit.cgi/linux/net-next.git/commit/include/net/tc_act?id=1d5e7c859e81a66674d194c346119d154d31e9dc'>net/sched: act_ife: Unexport ife_tlv_meta_encode</a></td><td>Yotam Gigi</td><td>1</td><td><span class='deletions'>-2</span>/<span class='insertions'>+0</span></td></tr>
<tr class='nohover-highlight'><td/><td colspan='5' class='logmsg'>
As the function ife_tlv_meta_encode is not used by any other module,
unexport it and make it static for the act_ife module.

Signed-off-by: Yotam Gigi &lt;yotamg@mellanox.com&gt;
Signed-off-by: Jamal Hadi Salim &lt;jhs@mojatatu.com&gt;
Signed-off-by: Roman Mashak &lt;mrv@mojatatu.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;


</td></tr>