linux/net/ncsi/ncsi-aen.c
Samuel Mendoza-Jonas 75e8e15635 net/ncsi: Don't take any action on HNCDSC AEN
The current HNCDSC handler takes the status flag from the AEN packet and
will update or change the current channel based on this flag and the
current channel status.

However the flag from the HNCDSC packet merely represents the host link
state. While the state of the host interface is potentially interesting
information it should not affect the state of the NCSI link. Indeed the
NCSI specification makes no mention of any recommended action related to
the host network controller driver state.

Update the HNCDSC handler to record the host network driver status but
take no other action.

Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-18 14:50:11 -05:00

207 lines
5.2 KiB
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);
netdev_info(ndp->ndev.dev, "NCSI: LSC AEN - channel %u state %s\n",
nc->id, data & 0x1 ? "up" : "down");
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;
spin_lock_irqsave(&nc->lock, flags);
ncm = &nc->modes[NCSI_MODE_LINK];
hncdsc = (struct ncsi_aen_hncdsc_pkt *)h;
ncm->data[3] = ntohl(hncdsc->status);
spin_unlock_irqrestore(&nc->lock, flags);
netdev_printk(KERN_DEBUG, ndp->ndev.dev,
"NCSI: host driver %srunning on channel %u\n",
ncm->data[3] & 0x1 ? "" : "not ", nc->id);
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, 8, 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) {
netdev_warn(ndp->ndev.dev,
"NCSI: 'bad' packet ignored for AEN type 0x%x\n",
h->type);
goto out;
}
ret = nah->handler(ndp, h);
if (ret)
netdev_err(ndp->ndev.dev,
"NCSI: Handler for AEN type 0x%x returned %d\n",
h->type, ret);
out:
consume_skb(skb);
return ret;
}