[linux-2.6-block.git] / net / ncsi / ncsi-aen.c

/*
 * Copyright Gavin Shan, IBM Corporation 2016.
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>

#include <net/ncsi.h>
#include <net/net_namespace.h>
#include <net/sock.h>

#include "internal.h"
#include "ncsi-pkt.h"

static int ncsi_validate_aen_pkt(struct ncsi_aen_pkt_hdr *h,
				 const unsigned short payload)
{
	u32 checksum;
	__be32 *pchecksum;

	if (h->common.revision != NCSI_PKT_REVISION)
		return -EINVAL;
	if (ntohs(h->common.length) != payload)
		return -EINVAL;

	/* Validate checksum, which might be zeroes if the
	 * sender doesn't support checksum according to NCSI
	 * specification.
	 */
	pchecksum = (__be32 *)((void *)(h + 1) + payload - 4);
	if (ntohl(*pchecksum) == 0)
		return 0;

	checksum = ncsi_calculate_checksum((unsigned char *)h,
					   sizeof(*h) + payload - 4);
	if (*pchecksum != htonl(checksum))
		return -EINVAL;

	return 0;
}

static int ncsi_aen_handler_lsc(struct ncsi_dev_priv *ndp,
				struct ncsi_aen_pkt_hdr *h)
{
	struct ncsi_aen_lsc_pkt *lsc;
	struct ncsi_channel *nc;
	struct ncsi_channel_mode *ncm;
	bool chained;
	int state;
	unsigned long old_data, data;
	unsigned long flags;

	/* Find the NCSI channel */
	ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc);
	if (!nc)
		return -ENODEV;

	/* Update the link status */
	lsc = (struct ncsi_aen_lsc_pkt *)h;

	spin_lock_irqsave(&nc->lock, flags);
	ncm = &nc->modes[NCSI_MODE_LINK];
	old_data = ncm->data[2];
	data = ntohl(lsc->status);
	ncm->data[2] = data;
	ncm->data[4] = ntohl(lsc->oem_status);

	chained = !list_empty(&nc->link);
	state = nc->state;
	spin_unlock_irqrestore(&nc->lock, flags);

	if (!((old_data ^ data) & 0x1) || chained)
		return 0;
	if (!(state == NCSI_CHANNEL_INACTIVE && (data & 0x1)) &&
	    !(state == NCSI_CHANNEL_ACTIVE && !(data & 0x1)))
		return 0;

	if (!(ndp->flags & NCSI_DEV_HWA) &&
	    state == NCSI_CHANNEL_ACTIVE)
		ndp->flags |= NCSI_DEV_RESHUFFLE;

	ncsi_stop_channel_monitor(nc);
	spin_lock_irqsave(&ndp->lock, flags);
	list_add_tail_rcu(&nc->link, &ndp->channel_queue);
	spin_unlock_irqrestore(&ndp->lock, flags);

	return ncsi_process_next_channel(ndp);
}

static int ncsi_aen_handler_cr(struct ncsi_dev_priv *ndp,
			       struct ncsi_aen_pkt_hdr *h)
{
	struct ncsi_channel *nc;
	unsigned long flags;

	/* Find the NCSI channel */
	ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc);
	if (!nc)
		return -ENODEV;

	spin_lock_irqsave(&nc->lock, flags);
	if (!list_empty(&nc->link) ||
	    nc->state != NCSI_CHANNEL_ACTIVE) {
		spin_unlock_irqrestore(&nc->lock, flags);
		return 0;
	}
	spin_unlock_irqrestore(&nc->lock, flags);

	ncsi_stop_channel_monitor(nc);
	spin_lock_irqsave(&nc->lock, flags);
	nc->state = NCSI_CHANNEL_INVISIBLE;
	spin_unlock_irqrestore(&nc->lock, flags);

	spin_lock_irqsave(&ndp->lock, flags);
	nc->state = NCSI_CHANNEL_INACTIVE;
	list_add_tail_rcu(&nc->link, &ndp->channel_queue);
	spin_unlock_irqrestore(&ndp->lock, flags);

	return ncsi_process_next_channel(ndp);
}

static int ncsi_aen_handler_hncdsc(struct ncsi_dev_priv *ndp,
				   struct ncsi_aen_pkt_hdr *h)
{
	struct ncsi_channel *nc;
	struct ncsi_channel_mode *ncm;
	struct ncsi_aen_hncdsc_pkt *hncdsc;
	unsigned long flags;

	/* Find the NCSI channel */
	ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc);
	if (!nc)
		return -ENODEV;

	/* If the channel is active one, we need reconfigure it */
	ncm = &nc->modes[NCSI_MODE_LINK];
	hncdsc = (struct ncsi_aen_hncdsc_pkt *)h;
	ncm->data[3] = ntohl(hncdsc->status);
	if (!list_empty(&nc->link) ||
	    nc->state != NCSI_CHANNEL_ACTIVE ||
	    (ncm->data[3] & 0x1))
		return 0;

	if (ndp->flags & NCSI_DEV_HWA)
		ndp->flags |= NCSI_DEV_RESHUFFLE;

	/* If this channel is the active one and the link doesn't
	 * work, we have to choose another channel to be active one.
	 * The logic here is exactly similar to what we do when link
	 * is down on the active channel.
	 */
	ncsi_stop_channel_monitor(nc);
	spin_lock_irqsave(&ndp->lock, flags);
	list_add_tail_rcu(&nc->link, &ndp->channel_queue);
	spin_unlock_irqrestore(&ndp->lock, flags);

	ncsi_process_next_channel(ndp);

	return 0;
}

static struct ncsi_aen_handler {
	unsigned char type;
	int           payload;
	int           (*handler)(struct ncsi_dev_priv *ndp,
				 struct ncsi_aen_pkt_hdr *h);
} ncsi_aen_handlers[] = {
	{ NCSI_PKT_AEN_LSC,    12, ncsi_aen_handler_lsc    },
	{ NCSI_PKT_AEN_CR,      4, ncsi_aen_handler_cr     },
	{ NCSI_PKT_AEN_HNCDSC,  4, ncsi_aen_handler_hncdsc }
};

int ncsi_aen_handler(struct ncsi_dev_priv *ndp, struct sk_buff *skb)
{
	struct ncsi_aen_pkt_hdr *h;
	struct ncsi_aen_handler *nah = NULL;
	int i, ret;

	/* Find the handler */
	h = (struct ncsi_aen_pkt_hdr *)skb_network_header(skb);
	for (i = 0; i < ARRAY_SIZE(ncsi_aen_handlers); i++) {
		if (ncsi_aen_handlers[i].type == h->type) {
			nah = &ncsi_aen_handlers[i];
			break;
		}
	}

	if (!nah) {
		netdev_warn(ndp->ndev.dev, "Invalid AEN (0x%x) received\n",
			    h->type);
		return -ENOENT;
	}

	ret = ncsi_validate_aen_pkt(h, nah->payload);
	if (ret)
		goto out;

	ret = nah->handler(ndp, h);
out:
	consume_skb(skb);
	return ret;
}
Commit	Line	Data
7a82ecf4 GS	1	/*
	2	* Copyright Gavin Shan, IBM Corporation 2016.
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation; either version 2 of the License, or
	7	* (at your option) any later version.
	8	*/
	9
	10	#include <linux/module.h>
	11	#include <linux/kernel.h>
	12	#include <linux/init.h>
	13	#include <linux/netdevice.h>
	14	#include <linux/skbuff.h>
	15
	16	#include <net/ncsi.h>
	17	#include <net/net_namespace.h>
	18	#include <net/sock.h>
	19
	20	#include "internal.h"
	21	#include "ncsi-pkt.h"
	22
	23	static int ncsi_validate_aen_pkt(struct ncsi_aen_pkt_hdr *h,
	24	const unsigned short payload)
	25	{
	26	u32 checksum;
	27	__be32 *pchecksum;
	28
	29	if (h->common.revision != NCSI_PKT_REVISION)
	30	return -EINVAL;
	31	if (ntohs(h->common.length) != payload)
	32	return -EINVAL;
	33
	34	/* Validate checksum, which might be zeroes if the
	35	* sender doesn't support checksum according to NCSI
	36	* specification.
	37	*/
	38	pchecksum = (__be32 )((void )(h + 1) + payload - 4);
	39	if (ntohl(*pchecksum) == 0)
	40	return 0;
	41
	42	checksum = ncsi_calculate_checksum((unsigned char *)h,
	43	sizeof(*h) + payload - 4);
	44	if (*pchecksum != htonl(checksum))
	45	return -EINVAL;
	46
	47	return 0;
	48	}
	49
	50	static int ncsi_aen_handler_lsc(struct ncsi_dev_priv *ndp,
	51	struct ncsi_aen_pkt_hdr *h)
	52	{
	53	struct ncsi_aen_lsc_pkt *lsc;
	54	struct ncsi_channel *nc;
	55	struct ncsi_channel_mode *ncm;
d8cedaab GS	56	bool chained;
	57	int state;
	58	unsigned long old_data, data;
7a82ecf4 GS	59	unsigned long flags;
	60
	61	/* Find the NCSI channel */
	62	ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc);
	63	if (!nc)
	64	return -ENODEV;
	65
	66	/* Update the link status */
7a82ecf4	67	lsc = (struct ncsi_aen_lsc_pkt *)h;
d8cedaab GS	68
	69	spin_lock_irqsave(&nc->lock, flags);
	70	ncm = &nc->modes[NCSI_MODE_LINK];
7a82ecf4	71	old_data = ncm->data[2];
d8cedaab GS	72	data = ntohl(lsc->status);
d8cedaab GS	73	ncm->data[2] = data;
7a82ecf4	74	ncm->data[4] = ntohl(lsc->oem_status);
d8cedaab GS	75
	76	chained = !list_empty(&nc->link);
	77	state = nc->state;
	78	spin_unlock_irqrestore(&nc->lock, flags);
	79
	80	if (!((old_data ^ data) & 0x1) \|\| chained)
7a82ecf4	81	return 0;
d8cedaab GS	82	if (!(state == NCSI_CHANNEL_INACTIVE && (data & 0x1)) &&
d8cedaab GS	83	!(state == NCSI_CHANNEL_ACTIVE && !(data & 0x1)))
7a82ecf4 GS	84	return 0;
	85
	86	if (!(ndp->flags & NCSI_DEV_HWA) &&
d8cedaab	87	state == NCSI_CHANNEL_ACTIVE)
7a82ecf4 GS	88	ndp->flags \|= NCSI_DEV_RESHUFFLE;
	89
	90	ncsi_stop_channel_monitor(nc);
	91	spin_lock_irqsave(&ndp->lock, flags);
	92	list_add_tail_rcu(&nc->link, &ndp->channel_queue);
	93	spin_unlock_irqrestore(&ndp->lock, flags);
	94
	95	return ncsi_process_next_channel(ndp);
	96	}
	97
	98	static int ncsi_aen_handler_cr(struct ncsi_dev_priv *ndp,
	99	struct ncsi_aen_pkt_hdr *h)
	100	{
	101	struct ncsi_channel *nc;
	102	unsigned long flags;
	103
	104	/* Find the NCSI channel */
	105	ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc);
	106	if (!nc)
	107	return -ENODEV;
	108
d8cedaab	109	spin_lock_irqsave(&nc->lock, flags);
7a82ecf4	110	if (!list_empty(&nc->link) \|\|
d8cedaab GS	111	nc->state != NCSI_CHANNEL_ACTIVE) {
d8cedaab GS	112	spin_unlock_irqrestore(&nc->lock, flags);
7a82ecf4	113	return 0;
d8cedaab GS	114	}
d8cedaab GS	115	spin_unlock_irqrestore(&nc->lock, flags);
7a82ecf4 GS	116
7a82ecf4 GS	117	ncsi_stop_channel_monitor(nc);
d8cedaab GS	118	spin_lock_irqsave(&nc->lock, flags);
	119	nc->state = NCSI_CHANNEL_INVISIBLE;
	120	spin_unlock_irqrestore(&nc->lock, flags);
	121
7a82ecf4	122	spin_lock_irqsave(&ndp->lock, flags);
d8cedaab	123	nc->state = NCSI_CHANNEL_INACTIVE;
7a82ecf4 GS	124	list_add_tail_rcu(&nc->link, &ndp->channel_queue);
	125	spin_unlock_irqrestore(&ndp->lock, flags);
	126
	127	return ncsi_process_next_channel(ndp);
	128	}
	129
	130	static int ncsi_aen_handler_hncdsc(struct ncsi_dev_priv *ndp,
	131	struct ncsi_aen_pkt_hdr *h)
	132	{
	133	struct ncsi_channel *nc;
	134	struct ncsi_channel_mode *ncm;
	135	struct ncsi_aen_hncdsc_pkt *hncdsc;
	136	unsigned long flags;
	137
	138	/* Find the NCSI channel */
	139	ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc);
	140	if (!nc)
	141	return -ENODEV;
	142
	143	/* If the channel is active one, we need reconfigure it */
	144	ncm = &nc->modes[NCSI_MODE_LINK];
	145	hncdsc = (struct ncsi_aen_hncdsc_pkt *)h;
	146	ncm->data[3] = ntohl(hncdsc->status);
	147	if (!list_empty(&nc->link) \|\|
	148	nc->state != NCSI_CHANNEL_ACTIVE \|\|
	149	(ncm->data[3] & 0x1))
	150	return 0;
	151
	152	if (ndp->flags & NCSI_DEV_HWA)
	153	ndp->flags \|= NCSI_DEV_RESHUFFLE;
	154
	155	/* If this channel is the active one and the link doesn't
	156	* work, we have to choose another channel to be active one.
	157	* The logic here is exactly similar to what we do when link
	158	* is down on the active channel.
	159	*/
	160	ncsi_stop_channel_monitor(nc);
	161	spin_lock_irqsave(&ndp->lock, flags);
	162	list_add_tail_rcu(&nc->link, &ndp->channel_queue);
	163	spin_unlock_irqrestore(&ndp->lock, flags);
	164
	165	ncsi_process_next_channel(ndp);
	166
	167	return 0;
	168	}
	169
	170	static struct ncsi_aen_handler {
	171	unsigned char type;
	172	int payload;
	173	int (handler)(struct ncsi_dev_priv ndp,
	174	struct ncsi_aen_pkt_hdr *h);
	175	} ncsi_aen_handlers[] = {
	176	{ NCSI_PKT_AEN_LSC, 12, ncsi_aen_handler_lsc },
	177	{ NCSI_PKT_AEN_CR, 4, ncsi_aen_handler_cr },
	178	{ NCSI_PKT_AEN_HNCDSC, 4, ncsi_aen_handler_hncdsc }
	179	};
	180
	181	int ncsi_aen_handler(struct ncsi_dev_priv ndp, struct sk_buff skb)
	182	{
	183	struct ncsi_aen_pkt_hdr *h;
	184	struct ncsi_aen_handler *nah = NULL;
	185	int i, ret;
	186
	187	/* Find the handler */
188	h = (struct ncsi_aen_pkt_hdr *)skb_network_header(skb);
189	for (i = 0; i < ARRAY_SIZE(ncsi_aen_handlers); i++) {
190	if (ncsi_aen_handlers[i].type == h->type) {
191	nah = &ncsi_aen_handlers[i];
192	break;
193	}
194	}
195
196	if (!nah) {
197	netdev_warn(ndp->ndev.dev, "Invalid AEN (0x%x) received\n",
198	h->type);
199	return -ENOENT;
200	}
201
202	ret = ncsi_validate_aen_pkt(h, nah->payload);
203	if (ret)
204	goto out;
205
206	ret = nah->handler(ndp, h);
207	out:
208	consume_skb(skb);
209	return ret;
210	}