linux/drivers/s390/net/qeth_l2_sys.c
Alexandra Winter 817741a8ea s390/qeth: Reset address notification in case of buffer overflow
In case hardware sends more device-to-bridge-address-change notfications
than the qeth-l2 driver can handle, the hardware will send an overflow
event and then stop sending any events. It expects software to flush its
FDB and start over again. Re-enabling address-change-notification will
report all current addresses.

In order to re-enable address-change-notification this patch defines
the functions qeth_l2_dev2br_an_set() and qeth_l2_dev2br_an_set_cb
to enable or disable dev-to-bridge-address-notification.

A following patch will use the learning_sync bridgeport flag to trigger
enabling or disabling of address-change-notification, so we define
priv->brport_features to store the current setting. BRIDGE_INFO and
ADDR_INFO functionality are mutually exclusive, whereas ADDR_INFO and
qeth_l2_vnicc* can be used together.

Alternative implementations to handle buffer overflow:
Just re-enabling notification and adding all newly reported addresses
would cover any lost 'add' events, but not the lost 'delete' events.
Then these invalid addresses would stay in the bridge FDB as long as the
device exists.
Setting the net device down and up, would be an alternative, but is a bit
drastic. If the net device has many secondary addresses this will create
many delete/add events at its peers which could de-stabilize the
network segment.

Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-15 13:21:47 -07:00

403 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright IBM Corp. 2013
* Author(s): Eugene Crosser <eugene.crosser@ru.ibm.com>
*/
#include <linux/slab.h>
#include <asm/ebcdic.h>
#include "qeth_core.h"
#include "qeth_l2.h"
static ssize_t qeth_bridge_port_role_state_show(struct device *dev,
struct device_attribute *attr, char *buf,
int show_state)
{
struct qeth_card *card = dev_get_drvdata(dev);
enum qeth_sbp_states state = QETH_SBP_STATE_INACTIVE;
int rc = 0;
char *word;
if (!qeth_bridgeport_allowed(card))
return sprintf(buf, "n/a (VNIC characteristics)\n");
mutex_lock(&card->sbp_lock);
if (qeth_card_hw_is_reachable(card) &&
card->options.sbp.supported_funcs)
rc = qeth_bridgeport_query_ports(card,
&card->options.sbp.role, &state);
if (!rc) {
if (show_state)
switch (state) {
case QETH_SBP_STATE_INACTIVE:
word = "inactive"; break;
case QETH_SBP_STATE_STANDBY:
word = "standby"; break;
case QETH_SBP_STATE_ACTIVE:
word = "active"; break;
default:
rc = -EIO;
}
else
switch (card->options.sbp.role) {
case QETH_SBP_ROLE_NONE:
word = "none"; break;
case QETH_SBP_ROLE_PRIMARY:
word = "primary"; break;
case QETH_SBP_ROLE_SECONDARY:
word = "secondary"; break;
default:
rc = -EIO;
}
if (rc)
QETH_CARD_TEXT_(card, 2, "SBP%02x:%02x",
card->options.sbp.role, state);
else
rc = sprintf(buf, "%s\n", word);
}
mutex_unlock(&card->sbp_lock);
return rc;
}
static ssize_t qeth_bridge_port_role_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct qeth_card *card = dev_get_drvdata(dev);
if (!qeth_bridgeport_allowed(card))
return sprintf(buf, "n/a (VNIC characteristics)\n");
return qeth_bridge_port_role_state_show(dev, attr, buf, 0);
}
static ssize_t qeth_bridge_port_role_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct qeth_card *card = dev_get_drvdata(dev);
int rc = 0;
enum qeth_sbp_roles role;
if (sysfs_streq(buf, "primary"))
role = QETH_SBP_ROLE_PRIMARY;
else if (sysfs_streq(buf, "secondary"))
role = QETH_SBP_ROLE_SECONDARY;
else if (sysfs_streq(buf, "none"))
role = QETH_SBP_ROLE_NONE;
else
return -EINVAL;
mutex_lock(&card->conf_mutex);
mutex_lock(&card->sbp_lock);
if (!qeth_bridgeport_allowed(card))
rc = -EBUSY;
else if (card->options.sbp.reflect_promisc)
/* Forbid direct manipulation */
rc = -EPERM;
else if (qeth_card_hw_is_reachable(card)) {
rc = qeth_bridgeport_setrole(card, role);
if (!rc)
card->options.sbp.role = role;
} else
card->options.sbp.role = role;
mutex_unlock(&card->sbp_lock);
mutex_unlock(&card->conf_mutex);
return rc ? rc : count;
}
static DEVICE_ATTR(bridge_role, 0644, qeth_bridge_port_role_show,
qeth_bridge_port_role_store);
static ssize_t qeth_bridge_port_state_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct qeth_card *card = dev_get_drvdata(dev);
if (!qeth_bridgeport_allowed(card))
return sprintf(buf, "n/a (VNIC characteristics)\n");
return qeth_bridge_port_role_state_show(dev, attr, buf, 1);
}
static DEVICE_ATTR(bridge_state, 0444, qeth_bridge_port_state_show,
NULL);
static ssize_t qeth_bridgeport_hostnotification_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct qeth_card *card = dev_get_drvdata(dev);
int enabled;
if (!qeth_bridgeport_allowed(card))
return sprintf(buf, "n/a (VNIC characteristics)\n");
enabled = card->options.sbp.hostnotification;
return sprintf(buf, "%d\n", enabled);
}
static ssize_t qeth_bridgeport_hostnotification_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct qeth_card *card = dev_get_drvdata(dev);
bool enable;
int rc;
rc = kstrtobool(buf, &enable);
if (rc)
return rc;
mutex_lock(&card->conf_mutex);
mutex_lock(&card->sbp_lock);
if (!qeth_bridgeport_allowed(card))
rc = -EBUSY;
else if (qeth_card_hw_is_reachable(card)) {
rc = qeth_bridgeport_an_set(card, enable);
/* sbp_lock ensures ordering vs notifications-stopped events */
if (!rc)
card->options.sbp.hostnotification = enable;
} else
card->options.sbp.hostnotification = enable;
mutex_unlock(&card->sbp_lock);
mutex_unlock(&card->conf_mutex);
return rc ? rc : count;
}
static DEVICE_ATTR(bridge_hostnotify, 0644,
qeth_bridgeport_hostnotification_show,
qeth_bridgeport_hostnotification_store);
static ssize_t qeth_bridgeport_reflect_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct qeth_card *card = dev_get_drvdata(dev);
char *state;
if (!qeth_bridgeport_allowed(card))
return sprintf(buf, "n/a (VNIC characteristics)\n");
if (card->options.sbp.reflect_promisc) {
if (card->options.sbp.reflect_promisc_primary)
state = "primary";
else
state = "secondary";
} else
state = "none";
return sprintf(buf, "%s\n", state);
}
static ssize_t qeth_bridgeport_reflect_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct qeth_card *card = dev_get_drvdata(dev);
int enable, primary;
int rc = 0;
if (sysfs_streq(buf, "none")) {
enable = 0;
primary = 0;
} else if (sysfs_streq(buf, "primary")) {
enable = 1;
primary = 1;
} else if (sysfs_streq(buf, "secondary")) {
enable = 1;
primary = 0;
} else
return -EINVAL;
mutex_lock(&card->conf_mutex);
mutex_lock(&card->sbp_lock);
if (!qeth_bridgeport_allowed(card))
rc = -EBUSY;
else if (card->options.sbp.role != QETH_SBP_ROLE_NONE)
rc = -EPERM;
else {
card->options.sbp.reflect_promisc = enable;
card->options.sbp.reflect_promisc_primary = primary;
rc = 0;
}
mutex_unlock(&card->sbp_lock);
mutex_unlock(&card->conf_mutex);
return rc ? rc : count;
}
static DEVICE_ATTR(bridge_reflect_promisc, 0644,
qeth_bridgeport_reflect_show,
qeth_bridgeport_reflect_store);
static struct attribute *qeth_l2_bridgeport_attrs[] = {
&dev_attr_bridge_role.attr,
&dev_attr_bridge_state.attr,
&dev_attr_bridge_hostnotify.attr,
&dev_attr_bridge_reflect_promisc.attr,
NULL,
};
static struct attribute_group qeth_l2_bridgeport_attr_group = {
.attrs = qeth_l2_bridgeport_attrs,
};
/* VNIC CHARS support */
/* convert sysfs attr name to VNIC characteristic */
static u32 qeth_l2_vnicc_sysfs_attr_to_char(const char *attr_name)
{
if (sysfs_streq(attr_name, "flooding"))
return QETH_VNICC_FLOODING;
else if (sysfs_streq(attr_name, "mcast_flooding"))
return QETH_VNICC_MCAST_FLOODING;
else if (sysfs_streq(attr_name, "learning"))
return QETH_VNICC_LEARNING;
else if (sysfs_streq(attr_name, "takeover_setvmac"))
return QETH_VNICC_TAKEOVER_SETVMAC;
else if (sysfs_streq(attr_name, "takeover_learning"))
return QETH_VNICC_TAKEOVER_LEARNING;
else if (sysfs_streq(attr_name, "bridge_invisible"))
return QETH_VNICC_BRIDGE_INVISIBLE;
else if (sysfs_streq(attr_name, "rx_bcast"))
return QETH_VNICC_RX_BCAST;
return 0;
}
/* get current timeout setting */
static ssize_t qeth_vnicc_timeout_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct qeth_card *card = dev_get_drvdata(dev);
u32 timeout;
int rc;
rc = qeth_l2_vnicc_get_timeout(card, &timeout);
if (rc == -EBUSY)
return sprintf(buf, "n/a (BridgePort)\n");
if (rc == -EOPNOTSUPP)
return sprintf(buf, "n/a\n");
return rc ? rc : sprintf(buf, "%d\n", timeout);
}
/* change timeout setting */
static ssize_t qeth_vnicc_timeout_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct qeth_card *card = dev_get_drvdata(dev);
u32 timeout;
int rc;
rc = kstrtou32(buf, 10, &timeout);
if (rc)
return rc;
mutex_lock(&card->conf_mutex);
rc = qeth_l2_vnicc_set_timeout(card, timeout);
mutex_unlock(&card->conf_mutex);
return rc ? rc : count;
}
/* get current setting of characteristic */
static ssize_t qeth_vnicc_char_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct qeth_card *card = dev_get_drvdata(dev);
bool state;
u32 vnicc;
int rc;
vnicc = qeth_l2_vnicc_sysfs_attr_to_char(attr->attr.name);
rc = qeth_l2_vnicc_get_state(card, vnicc, &state);
if (rc == -EBUSY)
return sprintf(buf, "n/a (BridgePort)\n");
if (rc == -EOPNOTSUPP)
return sprintf(buf, "n/a\n");
return rc ? rc : sprintf(buf, "%d\n", state);
}
/* change setting of characteristic */
static ssize_t qeth_vnicc_char_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct qeth_card *card = dev_get_drvdata(dev);
bool state;
u32 vnicc;
int rc;
if (kstrtobool(buf, &state))
return -EINVAL;
vnicc = qeth_l2_vnicc_sysfs_attr_to_char(attr->attr.name);
mutex_lock(&card->conf_mutex);
rc = qeth_l2_vnicc_set_state(card, vnicc, state);
mutex_unlock(&card->conf_mutex);
return rc ? rc : count;
}
static DEVICE_ATTR(flooding, 0644, qeth_vnicc_char_show, qeth_vnicc_char_store);
static DEVICE_ATTR(mcast_flooding, 0644, qeth_vnicc_char_show,
qeth_vnicc_char_store);
static DEVICE_ATTR(learning, 0644, qeth_vnicc_char_show, qeth_vnicc_char_store);
static DEVICE_ATTR(learning_timeout, 0644, qeth_vnicc_timeout_show,
qeth_vnicc_timeout_store);
static DEVICE_ATTR(takeover_setvmac, 0644, qeth_vnicc_char_show,
qeth_vnicc_char_store);
static DEVICE_ATTR(takeover_learning, 0644, qeth_vnicc_char_show,
qeth_vnicc_char_store);
static DEVICE_ATTR(bridge_invisible, 0644, qeth_vnicc_char_show,
qeth_vnicc_char_store);
static DEVICE_ATTR(rx_bcast, 0644, qeth_vnicc_char_show, qeth_vnicc_char_store);
static struct attribute *qeth_l2_vnicc_attrs[] = {
&dev_attr_flooding.attr,
&dev_attr_mcast_flooding.attr,
&dev_attr_learning.attr,
&dev_attr_learning_timeout.attr,
&dev_attr_takeover_setvmac.attr,
&dev_attr_takeover_learning.attr,
&dev_attr_bridge_invisible.attr,
&dev_attr_rx_bcast.attr,
NULL,
};
static struct attribute_group qeth_l2_vnicc_attr_group = {
.attrs = qeth_l2_vnicc_attrs,
.name = "vnicc",
};
static const struct attribute_group *qeth_l2_only_attr_groups[] = {
&qeth_l2_bridgeport_attr_group,
&qeth_l2_vnicc_attr_group,
NULL,
};
int qeth_l2_create_device_attributes(struct device *dev)
{
return sysfs_create_groups(&dev->kobj, qeth_l2_only_attr_groups);
}
void qeth_l2_remove_device_attributes(struct device *dev)
{
sysfs_remove_groups(&dev->kobj, qeth_l2_only_attr_groups);
}
const struct attribute_group *qeth_l2_attr_groups[] = {
&qeth_device_attr_group,
&qeth_device_blkt_group,
/* l2 specific, see qeth_l2_only_attr_groups: */
&qeth_l2_bridgeport_attr_group,
&qeth_l2_vnicc_attr_group,
NULL,
};