linux-stable/drivers/s390/net/qeth_l2_sys.c
Julian Wiedmann 2d2ebb3ed0 s390/qeth: unbreak OSM and OSN support
commit b4d72c08b3 ("qeth: bridgeport support - basic control")
broke the support for OSM and OSN devices as follows:

As OSM and OSN are L2 only, qeth_core_probe_device() does an early
setup by loading the l2 discipline and calling qeth_l2_probe_device().
In this context, adding the l2-specific bridgeport sysfs attributes
via qeth_l2_create_device_attributes() hits a BUG_ON in fs/sysfs/group.c,
since the basic sysfs infrastructure for the device hasn't been
established yet.

Note that OSN actually has its own unique sysfs attributes
(qeth_osn_devtype), so the additional attributes shouldn't be created
at all.
For OSM, add a new qeth_l2_devtype that contains all the common
and l2-specific sysfs attributes.
When qeth_core_probe_device() does early setup for OSM or OSN, assign
the corresponding devtype so that the ccwgroup probe code creates the
full set of sysfs attributes.
This allows us to skip qeth_l2_create_device_attributes() in case
of an early setup.

Any device that can't do early setup will initially have only the
generic sysfs attributes, and when it's probed later
qeth_l2_probe_device() adds the l2-specific attributes.

If an early-setup device is removed (by calling ccwgroup_ungroup()),
device_unregister() will - using the devtype - delete the
l2-specific attributes before qeth_l2_remove_device() is called.
So make sure to not remove them twice.

What complicates the issue is that qeth_l2_probe_device() and
qeth_l2_remove_device() is also called on a device when its
layer2 attribute changes (ie. its layer mode is switched).
For early-setup devices this wouldn't work properly - we wouldn't
remove the l2-specific attributes when switching to L3.
But switching the layer mode doesn't actually make any sense;
we already decided that the device can only operate in L2!
So just refuse to switch the layer mode on such devices. Note that
OSN doesn't have a layer2 attribute, so we only need to special-case
OSM.

Based on an initial patch by Ursula Braun.

Fixes: b4d72c08b3 ("qeth: bridgeport support - basic control")
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-11 12:37:48 -04:00

279 lines
6.5 KiB
C

/*
* 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 (!card)
return -EINVAL;
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);
}
return rc;
}
static ssize_t qeth_bridge_port_role_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
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 (!card)
return -EINVAL;
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);
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->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)
{
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 (!card)
return -EINVAL;
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);
int rc = 0;
int enable;
if (!card)
return -EINVAL;
if (sysfs_streq(buf, "0"))
enable = 0;
else if (sysfs_streq(buf, "1"))
enable = 1;
else
return -EINVAL;
mutex_lock(&card->conf_mutex);
if (qeth_card_hw_is_reachable(card)) {
rc = qeth_bridgeport_an_set(card, enable);
if (!rc)
card->options.sbp.hostnotification = enable;
} else
card->options.sbp.hostnotification = enable;
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 (!card)
return -EINVAL;
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 (!card)
return -EINVAL;
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);
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->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,
};
int qeth_l2_create_device_attributes(struct device *dev)
{
return sysfs_create_group(&dev->kobj, &qeth_l2_bridgeport_attr_group);
}
void qeth_l2_remove_device_attributes(struct device *dev)
{
sysfs_remove_group(&dev->kobj, &qeth_l2_bridgeport_attr_group);
}
/**
* qeth_l2_setup_bridgeport_attrs() - set/restore attrs when turning online.
* @card: qeth_card structure pointer
*
* Note: this function is called with conf_mutex held by the caller
*/
void qeth_l2_setup_bridgeport_attrs(struct qeth_card *card)
{
int rc;
if (!card)
return;
if (!card->options.sbp.supported_funcs)
return;
if (card->options.sbp.role != QETH_SBP_ROLE_NONE) {
/* Conditional to avoid spurious error messages */
qeth_bridgeport_setrole(card, card->options.sbp.role);
/* Let the callback function refresh the stored role value. */
qeth_bridgeport_query_ports(card,
&card->options.sbp.role, NULL);
}
if (card->options.sbp.hostnotification) {
rc = qeth_bridgeport_an_set(card, 1);
if (rc)
card->options.sbp.hostnotification = 0;
} else
qeth_bridgeport_an_set(card, 0);
}
const struct attribute_group *qeth_l2_attr_groups[] = {
&qeth_device_attr_group,
&qeth_device_blkt_group,
/* l2 specific, see l2_{create,remove}_device_attributes(): */
&qeth_l2_bridgeport_attr_group,
NULL,
};