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scsi_transport_iscsi.c
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scsi_transport_iscsi.c
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/*
* iSCSI transport class definitions
*
* Copyright (C) IBM Corporation, 2004
* Copyright (C) Mike Christie, 2004 - 2005
* Copyright (C) Dmitry Yusupov, 2004 - 2005
* Copyright (C) Alex Aizman, 2004 - 2005
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <linux/module.h>
#include <linux/mutex.h>
#include <net/tcp.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_iscsi.h>
#include <scsi/iscsi_if.h>
#define ISCSI_SESSION_ATTRS 19
#define ISCSI_CONN_ATTRS 13
#define ISCSI_HOST_ATTRS 4
#define ISCSI_TRANSPORT_VERSION "2.0-869"
struct iscsi_internal {
int daemon_pid;
struct scsi_transport_template t;
struct iscsi_transport *iscsi_transport;
struct list_head list;
struct class_device cdev;
struct class_device_attribute *host_attrs[ISCSI_HOST_ATTRS + 1];
struct transport_container conn_cont;
struct class_device_attribute *conn_attrs[ISCSI_CONN_ATTRS + 1];
struct transport_container session_cont;
struct class_device_attribute *session_attrs[ISCSI_SESSION_ATTRS + 1];
};
static atomic_t iscsi_session_nr; /* sysfs session id for next new session */
static struct workqueue_struct *iscsi_eh_timer_workq;
/*
* list of registered transports and lock that must
* be held while accessing list. The iscsi_transport_lock must
* be acquired after the rx_queue_mutex.
*/
static LIST_HEAD(iscsi_transports);
static DEFINE_SPINLOCK(iscsi_transport_lock);
#define to_iscsi_internal(tmpl) \
container_of(tmpl, struct iscsi_internal, t)
#define cdev_to_iscsi_internal(_cdev) \
container_of(_cdev, struct iscsi_internal, cdev)
static void iscsi_transport_release(struct class_device *cdev)
{
struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev);
kfree(priv);
}
/*
* iscsi_transport_class represents the iscsi_transports that are
* registered.
*/
static struct class iscsi_transport_class = {
.name = "iscsi_transport",
.release = iscsi_transport_release,
};
static ssize_t
show_transport_handle(struct class_device *cdev, char *buf)
{
struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev);
return sprintf(buf, "%llu\n", (unsigned long long)iscsi_handle(priv->iscsi_transport));
}
static CLASS_DEVICE_ATTR(handle, S_IRUGO, show_transport_handle, NULL);
#define show_transport_attr(name, format) \
static ssize_t \
show_transport_##name(struct class_device *cdev, char *buf) \
{ \
struct iscsi_internal *priv = cdev_to_iscsi_internal(cdev); \
return sprintf(buf, format"\n", priv->iscsi_transport->name); \
} \
static CLASS_DEVICE_ATTR(name, S_IRUGO, show_transport_##name, NULL);
show_transport_attr(caps, "0x%x");
show_transport_attr(max_lun, "%d");
show_transport_attr(max_conn, "%d");
show_transport_attr(max_cmd_len, "%d");
static struct attribute *iscsi_transport_attrs[] = {
&class_device_attr_handle.attr,
&class_device_attr_caps.attr,
&class_device_attr_max_lun.attr,
&class_device_attr_max_conn.attr,
&class_device_attr_max_cmd_len.attr,
NULL,
};
static struct attribute_group iscsi_transport_group = {
.attrs = iscsi_transport_attrs,
};
static int iscsi_setup_host(struct transport_container *tc, struct device *dev,
struct class_device *cdev)
{
struct Scsi_Host *shost = dev_to_shost(dev);
struct iscsi_host *ihost = shost->shost_data;
memset(ihost, 0, sizeof(*ihost));
INIT_LIST_HEAD(&ihost->sessions);
mutex_init(&ihost->mutex);
atomic_set(&ihost->nr_scans, 0);
snprintf(ihost->scan_workq_name, KOBJ_NAME_LEN, "iscsi_scan_%d",
shost->host_no);
ihost->scan_workq = create_singlethread_workqueue(
ihost->scan_workq_name);
if (!ihost->scan_workq)
return -ENOMEM;
return 0;
}
static int iscsi_remove_host(struct transport_container *tc, struct device *dev,
struct class_device *cdev)
{
struct Scsi_Host *shost = dev_to_shost(dev);
struct iscsi_host *ihost = shost->shost_data;
destroy_workqueue(ihost->scan_workq);
return 0;
}
static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
"iscsi_host",
iscsi_setup_host,
iscsi_remove_host,
NULL);
static DECLARE_TRANSPORT_CLASS(iscsi_session_class,
"iscsi_session",
NULL,
NULL,
NULL);
static DECLARE_TRANSPORT_CLASS(iscsi_connection_class,
"iscsi_connection",
NULL,
NULL,
NULL);
static struct sock *nls;
static DEFINE_MUTEX(rx_queue_mutex);
static LIST_HEAD(sesslist);
static DEFINE_SPINLOCK(sesslock);
static LIST_HEAD(connlist);
static DEFINE_SPINLOCK(connlock);
static uint32_t iscsi_conn_get_sid(struct iscsi_cls_conn *conn)
{
struct iscsi_cls_session *sess = iscsi_dev_to_session(conn->dev.parent);
return sess->sid;
}
/*
* Returns the matching session to a given sid
*/
static struct iscsi_cls_session *iscsi_session_lookup(uint32_t sid)
{
unsigned long flags;
struct iscsi_cls_session *sess;
spin_lock_irqsave(&sesslock, flags);
list_for_each_entry(sess, &sesslist, sess_list) {
if (sess->sid == sid) {
spin_unlock_irqrestore(&sesslock, flags);
return sess;
}
}
spin_unlock_irqrestore(&sesslock, flags);
return NULL;
}
/*
* Returns the matching connection to a given sid / cid tuple
*/
static struct iscsi_cls_conn *iscsi_conn_lookup(uint32_t sid, uint32_t cid)
{
unsigned long flags;
struct iscsi_cls_conn *conn;
spin_lock_irqsave(&connlock, flags);
list_for_each_entry(conn, &connlist, conn_list) {
if ((conn->cid == cid) && (iscsi_conn_get_sid(conn) == sid)) {
spin_unlock_irqrestore(&connlock, flags);
return conn;
}
}
spin_unlock_irqrestore(&connlock, flags);
return NULL;
}
/*
* The following functions can be used by LLDs that allocate
* their own scsi_hosts or by software iscsi LLDs
*/
static struct {
int value;
char *name;
} iscsi_session_state_names[] = {
{ ISCSI_SESSION_LOGGED_IN, "LOGGED_IN" },
{ ISCSI_SESSION_FAILED, "FAILED" },
{ ISCSI_SESSION_FREE, "FREE" },
};
static const char *iscsi_session_state_name(int state)
{
int i;
char *name = NULL;
for (i = 0; i < ARRAY_SIZE(iscsi_session_state_names); i++) {
if (iscsi_session_state_names[i].value == state) {
name = iscsi_session_state_names[i].name;
break;
}
}
return name;
}
int iscsi_session_chkready(struct iscsi_cls_session *session)
{
unsigned long flags;
int err;
spin_lock_irqsave(&session->lock, flags);
switch (session->state) {
case ISCSI_SESSION_LOGGED_IN:
err = 0;
break;
case ISCSI_SESSION_FAILED:
err = DID_IMM_RETRY << 16;
break;
case ISCSI_SESSION_FREE:
err = DID_NO_CONNECT << 16;
break;
default:
err = DID_NO_CONNECT << 16;
break;
}
spin_unlock_irqrestore(&session->lock, flags);
return err;
}
EXPORT_SYMBOL_GPL(iscsi_session_chkready);
static void iscsi_session_release(struct device *dev)
{
struct iscsi_cls_session *session = iscsi_dev_to_session(dev);
struct Scsi_Host *shost;
shost = iscsi_session_to_shost(session);
scsi_host_put(shost);
kfree(session);
}
static int iscsi_is_session_dev(const struct device *dev)
{
return dev->release == iscsi_session_release;
}
/**
* iscsi_scan_finished - helper to report when running scans are done
* @shost: scsi host
* @time: scan run time
*
* This function can be used by drives like qla4xxx to report to the scsi
* layer when the scans it kicked off at module load time are done.
*/
int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time)
{
struct iscsi_host *ihost = shost->shost_data;
/*
* qla4xxx will have kicked off some session unblocks before calling
* scsi_scan_host, so just wait for them to complete.
*/
return !atomic_read(&ihost->nr_scans);
}
EXPORT_SYMBOL_GPL(iscsi_scan_finished);
static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
uint id, uint lun)
{
struct iscsi_host *ihost = shost->shost_data;
struct iscsi_cls_session *session;
mutex_lock(&ihost->mutex);
list_for_each_entry(session, &ihost->sessions, host_list) {
if ((channel == SCAN_WILD_CARD || channel == 0) &&
(id == SCAN_WILD_CARD || id == session->target_id))
scsi_scan_target(&session->dev, 0,
session->target_id, lun, 1);
}
mutex_unlock(&ihost->mutex);
return 0;
}
static void iscsi_scan_session(struct work_struct *work)
{
struct iscsi_cls_session *session =
container_of(work, struct iscsi_cls_session, scan_work);
struct Scsi_Host *shost = iscsi_session_to_shost(session);
struct iscsi_host *ihost = shost->shost_data;
unsigned long flags;
spin_lock_irqsave(&session->lock, flags);
if (session->state != ISCSI_SESSION_LOGGED_IN) {
spin_unlock_irqrestore(&session->lock, flags);
goto done;
}
spin_unlock_irqrestore(&session->lock, flags);
scsi_scan_target(&session->dev, 0, session->target_id,
SCAN_WILD_CARD, 1);
done:
atomic_dec(&ihost->nr_scans);
}
static void session_recovery_timedout(struct work_struct *work)
{
struct iscsi_cls_session *session =
container_of(work, struct iscsi_cls_session,
recovery_work.work);
unsigned long flags;
iscsi_cls_session_printk(KERN_INFO, session,
"session recovery timed out after %d secs\n",
session->recovery_tmo);
spin_lock_irqsave(&session->lock, flags);
switch (session->state) {
case ISCSI_SESSION_FAILED:
session->state = ISCSI_SESSION_FREE;
break;
case ISCSI_SESSION_LOGGED_IN:
case ISCSI_SESSION_FREE:
/* we raced with the unblock's flush */
spin_unlock_irqrestore(&session->lock, flags);
return;
}
spin_unlock_irqrestore(&session->lock, flags);
if (session->transport->session_recovery_timedout)
session->transport->session_recovery_timedout(session);
scsi_target_unblock(&session->dev);
}
static void __iscsi_unblock_session(struct work_struct *work)
{
struct iscsi_cls_session *session =
container_of(work, struct iscsi_cls_session,
unblock_work);
struct Scsi_Host *shost = iscsi_session_to_shost(session);
struct iscsi_host *ihost = shost->shost_data;
unsigned long flags;
/*
* The recovery and unblock work get run from the same workqueue,
* so try to cancel it if it was going to run after this unblock.
*/
cancel_delayed_work(&session->recovery_work);
spin_lock_irqsave(&session->lock, flags);
session->state = ISCSI_SESSION_LOGGED_IN;
spin_unlock_irqrestore(&session->lock, flags);
/* start IO */
scsi_target_unblock(&session->dev);
/*
* Only do kernel scanning if the driver is properly hooked into
* the async scanning code (drivers like iscsi_tcp do login and
* scanning from userspace).
*/
if (shost->hostt->scan_finished) {
if (queue_work(ihost->scan_workq, &session->scan_work))
atomic_inc(&ihost->nr_scans);
}
}
/**
* iscsi_unblock_session - set a session as logged in and start IO.
* @session: iscsi session
*
* Mark a session as ready to accept IO.
*/
void iscsi_unblock_session(struct iscsi_cls_session *session)
{
queue_work(iscsi_eh_timer_workq, &session->unblock_work);
/*
* make sure all the events have completed before tell the driver
* it is safe
*/
flush_workqueue(iscsi_eh_timer_workq);
}
EXPORT_SYMBOL_GPL(iscsi_unblock_session);
static void __iscsi_block_session(struct work_struct *work)
{
struct iscsi_cls_session *session =
container_of(work, struct iscsi_cls_session,
block_work);
unsigned long flags;
spin_lock_irqsave(&session->lock, flags);
session->state = ISCSI_SESSION_FAILED;
spin_unlock_irqrestore(&session->lock, flags);
scsi_target_block(&session->dev);
queue_delayed_work(iscsi_eh_timer_workq, &session->recovery_work,
session->recovery_tmo * HZ);
}
void iscsi_block_session(struct iscsi_cls_session *session)
{
queue_work(iscsi_eh_timer_workq, &session->block_work);
}
EXPORT_SYMBOL_GPL(iscsi_block_session);
static void __iscsi_unbind_session(struct work_struct *work)
{
struct iscsi_cls_session *session =
container_of(work, struct iscsi_cls_session,
unbind_work);
struct Scsi_Host *shost = iscsi_session_to_shost(session);
struct iscsi_host *ihost = shost->shost_data;
/* Prevent new scans and make sure scanning is not in progress */
mutex_lock(&ihost->mutex);
if (list_empty(&session->host_list)) {
mutex_unlock(&ihost->mutex);
return;
}
list_del_init(&session->host_list);
mutex_unlock(&ihost->mutex);
scsi_remove_target(&session->dev);
iscsi_session_event(session, ISCSI_KEVENT_UNBIND_SESSION);
}
static int iscsi_unbind_session(struct iscsi_cls_session *session)
{
struct Scsi_Host *shost = iscsi_session_to_shost(session);
struct iscsi_host *ihost = shost->shost_data;
return queue_work(ihost->scan_workq, &session->unbind_work);
}
struct iscsi_cls_session *
iscsi_alloc_session(struct Scsi_Host *shost,
struct iscsi_transport *transport)
{
struct iscsi_cls_session *session;
session = kzalloc(sizeof(*session) + transport->sessiondata_size,
GFP_KERNEL);
if (!session)
return NULL;
session->transport = transport;
session->recovery_tmo = 120;
session->state = ISCSI_SESSION_FREE;
INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
INIT_LIST_HEAD(&session->host_list);
INIT_LIST_HEAD(&session->sess_list);
INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
INIT_WORK(&session->block_work, __iscsi_block_session);
INIT_WORK(&session->unbind_work, __iscsi_unbind_session);
INIT_WORK(&session->scan_work, iscsi_scan_session);
spin_lock_init(&session->lock);
/* this is released in the dev's release function */
scsi_host_get(shost);
session->dev.parent = &shost->shost_gendev;
session->dev.release = iscsi_session_release;
device_initialize(&session->dev);
if (transport->sessiondata_size)
session->dd_data = &session[1];
return session;
}
EXPORT_SYMBOL_GPL(iscsi_alloc_session);
int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
{
struct Scsi_Host *shost = iscsi_session_to_shost(session);
struct iscsi_host *ihost;
unsigned long flags;
int err;
ihost = shost->shost_data;
session->sid = atomic_add_return(1, &iscsi_session_nr);
session->target_id = target_id;
snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u",
session->sid);
err = device_add(&session->dev);
if (err) {
iscsi_cls_session_printk(KERN_ERR, session,
"could not register session's dev\n");
goto release_host;
}
transport_register_device(&session->dev);
spin_lock_irqsave(&sesslock, flags);
list_add(&session->sess_list, &sesslist);
spin_unlock_irqrestore(&sesslock, flags);
mutex_lock(&ihost->mutex);
list_add(&session->host_list, &ihost->sessions);
mutex_unlock(&ihost->mutex);
iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
return 0;
release_host:
scsi_host_put(shost);
return err;
}
EXPORT_SYMBOL_GPL(iscsi_add_session);
/**
* iscsi_create_session - create iscsi class session
* @shost: scsi host
* @transport: iscsi transport
* @target_id: which target
*
* This can be called from a LLD or iscsi_transport.
*/
struct iscsi_cls_session *
iscsi_create_session(struct Scsi_Host *shost,
struct iscsi_transport *transport,
unsigned int target_id)
{
struct iscsi_cls_session *session;
session = iscsi_alloc_session(shost, transport);
if (!session)
return NULL;
if (iscsi_add_session(session, target_id)) {
iscsi_free_session(session);
return NULL;
}
return session;
}
EXPORT_SYMBOL_GPL(iscsi_create_session);
static void iscsi_conn_release(struct device *dev)
{
struct iscsi_cls_conn *conn = iscsi_dev_to_conn(dev);
struct device *parent = conn->dev.parent;
kfree(conn);
put_device(parent);
}
static int iscsi_is_conn_dev(const struct device *dev)
{
return dev->release == iscsi_conn_release;
}
static int iscsi_iter_destroy_conn_fn(struct device *dev, void *data)
{
if (!iscsi_is_conn_dev(dev))
return 0;
return iscsi_destroy_conn(iscsi_dev_to_conn(dev));
}
void iscsi_remove_session(struct iscsi_cls_session *session)
{
struct Scsi_Host *shost = iscsi_session_to_shost(session);
struct iscsi_host *ihost = shost->shost_data;
unsigned long flags;
int err;
spin_lock_irqsave(&sesslock, flags);
list_del(&session->sess_list);
spin_unlock_irqrestore(&sesslock, flags);
/* make sure there are no blocks/unblocks queued */
flush_workqueue(iscsi_eh_timer_workq);
/* make sure the timedout callout is not running */
if (!cancel_delayed_work(&session->recovery_work))
flush_workqueue(iscsi_eh_timer_workq);
/*
* If we are blocked let commands flow again. The lld or iscsi
* layer should set up the queuecommand to fail commands.
* We assume that LLD will not be calling block/unblock while
* removing the session.
*/
spin_lock_irqsave(&session->lock, flags);
session->state = ISCSI_SESSION_FREE;
spin_unlock_irqrestore(&session->lock, flags);
scsi_target_unblock(&session->dev);
/* flush running scans then delete devices */
flush_workqueue(ihost->scan_workq);
__iscsi_unbind_session(&session->unbind_work);
/* hw iscsi may not have removed all connections from session */
err = device_for_each_child(&session->dev, NULL,
iscsi_iter_destroy_conn_fn);
if (err)
iscsi_cls_session_printk(KERN_ERR, session,
"Could not delete all connections "
"for session. Error %d.\n", err);
transport_unregister_device(&session->dev);
device_del(&session->dev);
}
EXPORT_SYMBOL_GPL(iscsi_remove_session);
void iscsi_free_session(struct iscsi_cls_session *session)
{
iscsi_session_event(session, ISCSI_KEVENT_DESTROY_SESSION);
put_device(&session->dev);
}
EXPORT_SYMBOL_GPL(iscsi_free_session);
/**
* iscsi_destroy_session - destroy iscsi session
* @session: iscsi_session
*
* Can be called by a LLD or iscsi_transport. There must not be
* any running connections.
*/
int iscsi_destroy_session(struct iscsi_cls_session *session)
{
iscsi_remove_session(session);
iscsi_free_session(session);
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_destroy_session);
/**
* iscsi_create_conn - create iscsi class connection
* @session: iscsi cls session
* @cid: connection id
*
* This can be called from a LLD or iscsi_transport. The connection
* is child of the session so cid must be unique for all connections
* on the session.
*
* Since we do not support MCS, cid will normally be zero. In some cases
* for software iscsi we could be trying to preallocate a connection struct
* in which case there could be two connection structs and cid would be
* non-zero.
*/
struct iscsi_cls_conn *
iscsi_create_conn(struct iscsi_cls_session *session, uint32_t cid)
{
struct iscsi_transport *transport = session->transport;
struct iscsi_cls_conn *conn;
unsigned long flags;
int err;
conn = kzalloc(sizeof(*conn) + transport->conndata_size, GFP_KERNEL);
if (!conn)
return NULL;
if (transport->conndata_size)
conn->dd_data = &conn[1];
INIT_LIST_HEAD(&conn->conn_list);
conn->transport = transport;
conn->cid = cid;
/* this is released in the dev's release function */
if (!get_device(&session->dev))
goto free_conn;
snprintf(conn->dev.bus_id, BUS_ID_SIZE, "connection%d:%u",
session->sid, cid);
conn->dev.parent = &session->dev;
conn->dev.release = iscsi_conn_release;
err = device_register(&conn->dev);
if (err) {
iscsi_cls_session_printk(KERN_ERR, session, "could not "
"register connection's dev\n");
goto release_parent_ref;
}
transport_register_device(&conn->dev);
spin_lock_irqsave(&connlock, flags);
list_add(&conn->conn_list, &connlist);
conn->active = 1;
spin_unlock_irqrestore(&connlock, flags);
return conn;
release_parent_ref:
put_device(&session->dev);
free_conn:
kfree(conn);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_create_conn);
/**
* iscsi_destroy_conn - destroy iscsi class connection
* @conn: iscsi cls session
*
* This can be called from a LLD or iscsi_transport.
*/
int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
{
unsigned long flags;
spin_lock_irqsave(&connlock, flags);
conn->active = 0;
list_del(&conn->conn_list);
spin_unlock_irqrestore(&connlock, flags);
transport_unregister_device(&conn->dev);
device_unregister(&conn->dev);
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_destroy_conn);
/*
* iscsi interface functions
*/
static struct iscsi_internal *
iscsi_if_transport_lookup(struct iscsi_transport *tt)
{
struct iscsi_internal *priv;
unsigned long flags;
spin_lock_irqsave(&iscsi_transport_lock, flags);
list_for_each_entry(priv, &iscsi_transports, list) {
if (tt == priv->iscsi_transport) {
spin_unlock_irqrestore(&iscsi_transport_lock, flags);
return priv;
}
}
spin_unlock_irqrestore(&iscsi_transport_lock, flags);
return NULL;
}
static int
iscsi_broadcast_skb(struct sk_buff *skb, gfp_t gfp)
{
int rc;
rc = netlink_broadcast(nls, skb, 0, 1, gfp);
if (rc < 0) {
printk(KERN_ERR "iscsi: can not broadcast skb (%d)\n", rc);
return rc;
}
return 0;
}
static int
iscsi_unicast_skb(struct sk_buff *skb, int pid)
{
int rc;
rc = netlink_unicast(nls, skb, pid, MSG_DONTWAIT);
if (rc < 0) {
printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
return rc;
}
return 0;
}
int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
char *data, uint32_t data_size)
{
struct nlmsghdr *nlh;
struct sk_buff *skb;
struct iscsi_uevent *ev;
char *pdu;
struct iscsi_internal *priv;
int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
data_size);
priv = iscsi_if_transport_lookup(conn->transport);
if (!priv)
return -EINVAL;
skb = alloc_skb(len, GFP_ATOMIC);
if (!skb) {
iscsi_conn_error(conn, ISCSI_ERR_CONN_FAILED);
iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
"control PDU: OOM\n");
return -ENOMEM;
}
nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
ev = NLMSG_DATA(nlh);
memset(ev, 0, sizeof(*ev));
ev->transport_handle = iscsi_handle(conn->transport);
ev->type = ISCSI_KEVENT_RECV_PDU;
ev->r.recv_req.cid = conn->cid;
ev->r.recv_req.sid = iscsi_conn_get_sid(conn);
pdu = (char*)ev + sizeof(*ev);
memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
return iscsi_unicast_skb(skb, priv->daemon_pid);
}
EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error)
{
struct nlmsghdr *nlh;
struct sk_buff *skb;
struct iscsi_uevent *ev;
struct iscsi_internal *priv;
int len = NLMSG_SPACE(sizeof(*ev));
priv = iscsi_if_transport_lookup(conn->transport);
if (!priv)
return;
skb = alloc_skb(len, GFP_ATOMIC);
if (!skb) {
iscsi_cls_conn_printk(KERN_ERR, conn, "gracefully ignored "
"conn error (%d)\n", error);
return;
}
nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
ev = NLMSG_DATA(nlh);
ev->transport_handle = iscsi_handle(conn->transport);
ev->type = ISCSI_KEVENT_CONN_ERROR;
ev->r.connerror.error = error;
ev->r.connerror.cid = conn->cid;
ev->r.connerror.sid = iscsi_conn_get_sid(conn);
iscsi_broadcast_skb(skb, GFP_ATOMIC);
iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
error);
}
EXPORT_SYMBOL_GPL(iscsi_conn_error);
static int
iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
void *payload, int size)
{
struct sk_buff *skb;
struct nlmsghdr *nlh;
int len = NLMSG_SPACE(size);
int flags = multi ? NLM_F_MULTI : 0;
int t = done ? NLMSG_DONE : type;
skb = alloc_skb(len, GFP_ATOMIC);
if (!skb) {
printk(KERN_ERR "Could not allocate skb to send reply.\n");
return -ENOMEM;
}
nlh = __nlmsg_put(skb, pid, seq, t, (len - sizeof(*nlh)), 0);
nlh->nlmsg_flags = flags;
memcpy(NLMSG_DATA(nlh), payload, size);
return iscsi_unicast_skb(skb, pid);
}
static int
iscsi_if_get_stats(struct iscsi_transport *transport, struct nlmsghdr *nlh)
{
struct iscsi_uevent *ev = NLMSG_DATA(nlh);
struct iscsi_stats *stats;
struct sk_buff *skbstat;
struct iscsi_cls_conn *conn;
struct nlmsghdr *nlhstat;
struct iscsi_uevent *evstat;
struct iscsi_internal *priv;
int len = NLMSG_SPACE(sizeof(*ev) +
sizeof(struct iscsi_stats) +
sizeof(struct iscsi_stats_custom) *
ISCSI_STATS_CUSTOM_MAX);
int err = 0;
priv = iscsi_if_transport_lookup(transport);
if (!priv)
return -EINVAL;
conn = iscsi_conn_lookup(ev->u.get_stats.sid, ev->u.get_stats.cid);
if (!conn)
return -EEXIST;
do {
int actual_size;
skbstat = alloc_skb(len, GFP_ATOMIC);
if (!skbstat) {
iscsi_cls_conn_printk(KERN_ERR, conn, "can not "
"deliver stats: OOM\n");
return -ENOMEM;
}
nlhstat = __nlmsg_put(skbstat, priv->daemon_pid, 0, 0,
(len - sizeof(*nlhstat)), 0);
evstat = NLMSG_DATA(nlhstat);
memset(evstat, 0, sizeof(*evstat));
evstat->transport_handle = iscsi_handle(conn->transport);
evstat->type = nlh->nlmsg_type;
evstat->u.get_stats.cid =
ev->u.get_stats.cid;
evstat->u.get_stats.sid =
ev->u.get_stats.sid;
stats = (struct iscsi_stats *)
((char*)evstat + sizeof(*evstat));
memset(stats, 0, sizeof(*stats));
transport->get_stats(conn, stats);
actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
sizeof(struct iscsi_stats) +
sizeof(struct iscsi_stats_custom) *
stats->custom_length);
actual_size -= sizeof(*nlhstat);
actual_size = NLMSG_LENGTH(actual_size);
skb_trim(skbstat, NLMSG_ALIGN(actual_size));
nlhstat->nlmsg_len = actual_size;
err = iscsi_unicast_skb(skbstat, priv->daemon_pid);
} while (err < 0 && err != -ECONNREFUSED);
return err;
}
/**
* iscsi_session_event - send session destr. completion event
* @session: iscsi class session
* @event: type of event
*/
int iscsi_session_event(struct iscsi_cls_session *session,
enum iscsi_uevent_e event)
{
struct iscsi_internal *priv;
struct Scsi_Host *shost;
struct iscsi_uevent *ev;
struct sk_buff *skb;
struct nlmsghdr *nlh;
int rc, len = NLMSG_SPACE(sizeof(*ev));
priv = iscsi_if_transport_lookup(session->transport);
if (!priv)
return -EINVAL;
shost = iscsi_session_to_shost(session);
skb = alloc_skb(len, GFP_KERNEL);
if (!skb) {
iscsi_cls_session_printk(KERN_ERR, session,
"Cannot notify userspace of session "
"event %u\n", event);
return -ENOMEM;
}
nlh = __nlmsg_put(skb, priv->daemon_pid, 0, 0, (len - sizeof(*nlh)), 0);
ev = NLMSG_DATA(nlh);
ev->transport_handle = iscsi_handle(session->transport);
ev->type = event;
switch (event) {
case ISCSI_KEVENT_DESTROY_SESSION:
ev->r.d_session.host_no = shost->host_no;
ev->r.d_session.sid = session->sid;
break;
case ISCSI_KEVENT_CREATE_SESSION:
ev->r.c_session_ret.host_no = shost->host_no;
ev->r.c_session_ret.sid = session->sid;
break;
case ISCSI_KEVENT_UNBIND_SESSION:
ev->r.unbind_session.host_no = shost->host_no;
ev->r.unbind_session.sid = session->sid;
break;
default:
iscsi_cls_session_printk(KERN_ERR, session, "Invalid event "
"%u.\n", event);
kfree_skb(skb);
return -EINVAL;