blob: 2d3baa99ca25d2352332945044e83c88ad477b10 [file] [log] [blame]
/*
* 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 11
#define ISCSI_CONN_ATTRS 11
#define ISCSI_HOST_ATTRS 0
#define ISCSI_TRANSPORT_VERSION "2.0-685"
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 int iscsi_session_nr; /* sysfs session id for next new session */
/*
* 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);
return 0;
}
static DECLARE_TRANSPORT_CLASS(iscsi_host_class,
"iscsi_host",
iscsi_setup_host,
NULL,
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 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;
}
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 session_recovery_timedout(void *data)
{
struct iscsi_cls_session *session = data;
dev_printk(KERN_INFO, &session->dev, "iscsi: session recovery timed "
"out after %d secs\n", session->recovery_tmo);
if (session->transport->session_recovery_timedout)
session->transport->session_recovery_timedout(session);
scsi_target_unblock(&session->dev);
}
void iscsi_unblock_session(struct iscsi_cls_session *session)
{
if (!cancel_delayed_work(&session->recovery_work))
flush_scheduled_work();
scsi_target_unblock(&session->dev);
}
EXPORT_SYMBOL_GPL(iscsi_unblock_session);
void iscsi_block_session(struct iscsi_cls_session *session)
{
scsi_target_block(&session->dev);
schedule_delayed_work(&session->recovery_work,
session->recovery_tmo * HZ);
}
EXPORT_SYMBOL_GPL(iscsi_block_session);
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;
INIT_WORK(&session->recovery_work, session_recovery_timedout, session);
INIT_LIST_HEAD(&session->host_list);
INIT_LIST_HEAD(&session->sess_list);
/* 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;
int err;
ihost = shost->shost_data;
session->sid = 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) {
dev_printk(KERN_ERR, &session->dev, "iscsi: could not "
"register session's dev\n");
goto release_host;
}
transport_register_device(&session->dev);
mutex_lock(&ihost->mutex);
list_add(&session->host_list, &ihost->sessions);
mutex_unlock(&ihost->mutex);
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
*
* 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);
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;
if (!cancel_delayed_work(&session->recovery_work))
flush_scheduled_work();
mutex_lock(&ihost->mutex);
list_del(&session->host_list);
mutex_unlock(&ihost->mutex);
scsi_remove_target(&session->dev);
transport_unregister_device(&session->dev);
device_del(&session->dev);
}
EXPORT_SYMBOL_GPL(iscsi_remove_session);
void iscsi_free_session(struct iscsi_cls_session *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);
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;
}
/**
* 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;
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) {
dev_printk(KERN_ERR, &conn->dev, "iscsi: could not register "
"connection's dev\n");
goto release_parent_ref;
}
transport_register_device(&conn->dev);
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
* @session: iscsi cls session
*
* This can be called from a LLD or iscsi_transport.
**/
int iscsi_destroy_conn(struct iscsi_cls_conn *conn)
{
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);
dev_printk(KERN_ERR, &conn->dev, "iscsi: 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) {
dev_printk(KERN_ERR, &conn->dev, "iscsi: 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);
dev_printk(KERN_INFO, &conn->dev, "iscsi: 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);
/*
* FIXME:
* user is supposed to react on iferror == -ENOMEM;
* see iscsi_if_rx().
*/
BUG_ON(!skb);
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) {
dev_printk(KERN_ERR, &conn->dev, "iscsi: 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_if_destroy_session_done - send session destr. completion event
* @conn: last connection for session
*
* This is called by HW iscsi LLDs to notify userpsace that its HW has
* removed a session.
**/
int iscsi_if_destroy_session_done(struct iscsi_cls_conn *conn)
{
struct iscsi_internal *priv;
struct iscsi_cls_session *session;
struct Scsi_Host *shost;
struct iscsi_uevent *ev;
struct sk_buff *skb;
struct nlmsghdr *nlh;
unsigned long flags;
int rc, len = NLMSG_SPACE(sizeof(*ev));
priv = iscsi_if_transport_lookup(conn->transport);
if (!priv)
return -EINVAL;
session = iscsi_dev_to_session(conn->dev.parent);
shost = iscsi_session_to_shost(session);
skb = alloc_skb(len, GFP_KERNEL);
if (!skb) {
dev_printk(KERN_ERR, &conn->dev, "Cannot notify userspace of "
"session creation event\n");
return -ENOMEM;
}
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_DESTROY_SESSION;
ev->r.d_session.host_no = shost->host_no;
ev->r.d_session.sid = session->sid;
/*
* this will occur if the daemon is not up, so we just warn
* the user and when the daemon is restarted it will handle it
*/
rc = iscsi_broadcast_skb(skb, GFP_KERNEL);
if (rc < 0)
dev_printk(KERN_ERR, &conn->dev, "Cannot notify userspace of "
"session destruction event. Check iscsi daemon\n");
spin_lock_irqsave(&sesslock, flags);
list_del(&session->sess_list);
spin_unlock_irqrestore(&sesslock, flags);
spin_lock_irqsave(&connlock, flags);
conn->active = 0;
list_del(&conn->conn_list);
spin_unlock_irqrestore(&connlock, flags);
return rc;
}
EXPORT_SYMBOL_GPL(iscsi_if_destroy_session_done);
/**
* iscsi_if_create_session_done - send session creation completion event
* @conn: leading connection for session
*
* This is called by HW iscsi LLDs to notify userpsace that its HW has
* created a session or a existing session is back in the logged in state.
**/
int iscsi_if_create_session_done(struct iscsi_cls_conn *conn)
{
struct iscsi_internal *priv;
struct iscsi_cls_session *session;
struct Scsi_Host *shost;
struct iscsi_uevent *ev;
struct sk_buff *skb;
struct nlmsghdr *nlh;
unsigned long flags;
int rc, len = NLMSG_SPACE(sizeof(*ev));
priv = iscsi_if_transport_lookup(conn->transport);
if (!priv)
return -EINVAL;
session = iscsi_dev_to_session(conn->dev.parent);
shost = iscsi_session_to_shost(session);
skb = alloc_skb(len, GFP_KERNEL);
if (!skb) {
dev_printk(KERN_ERR, &conn->dev, "Cannot notify userspace of "
"session creation event\n");
return -ENOMEM;
}
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_UEVENT_CREATE_SESSION;
ev->r.c_session_ret.host_no = shost->host_no;
ev->r.c_session_ret.sid = session->sid;
/*
* this will occur if the daemon is not up, so we just warn
* the user and when the daemon is restarted it will handle it
*/
rc = iscsi_broadcast_skb(skb, GFP_KERNEL);
if (rc < 0)
dev_printk(KERN_ERR, &conn->dev, "Cannot notify userspace of "
"session creation event. Check iscsi daemon\n");
spin_lock_irqsave(&sesslock, flags);
list_add(&session->sess_list, &sesslist);
spin_unlock_irqrestore(&sesslock, flags);
spin_lock_irqsave(&connlock, flags);
list_add(&conn->conn_list, &connlist);
conn->active = 1;
spin_unlock_irqrestore(&connlock, flags);
return rc;
}
EXPORT_SYMBOL_GPL(iscsi_if_create_session_done);
static int
iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
{
struct iscsi_transport *transport = priv->iscsi_transport;
struct iscsi_cls_session *session;
unsigned long flags;
uint32_t hostno;
session = transport->create_session(transport, &priv->t,
ev->u.c_session.initial_cmdsn,
&hostno);
if (!session)
return -ENOMEM;
spin_lock_irqsave(&sesslock, flags);
list_add(&session->sess_list, &sesslist);
spin_unlock_irqrestore(&sesslock, flags);
ev->r.c_session_ret.host_no = hostno;
ev->r.c_session_ret.sid = session->sid;
return 0;
}
static int
iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
{
struct iscsi_cls_conn *conn;
struct iscsi_cls_session *session;
unsigned long flags;
session = iscsi_session_lookup(ev->u.c_conn.sid);
if (!session) {
printk(KERN_ERR "iscsi: invalid session %d\n",
ev->u.c_conn.sid);
return -EINVAL;
}
conn = transport->create_conn(session, ev->u.c_conn.cid);
if (!conn) {
printk(KERN_ERR "iscsi: couldn't create a new "
"connection for session %d\n",
session->sid);
return -ENOMEM;
}
ev->r.c_conn_ret.sid = session->sid;
ev->r.c_conn_ret.cid = conn->cid;
spin_lock_irqsave(&connlock, flags);
list_add(&conn->conn_list, &connlist);
conn->active = 1;
spin_unlock_irqrestore(&connlock, flags);
return 0;
}
static int
iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
{
unsigned long flags;
struct iscsi_cls_conn *conn;
conn = iscsi_conn_lookup(ev->u.d_conn.sid, ev->u.d_conn.cid);
if (!conn)
return -EINVAL;
spin_lock_irqsave(&connlock, flags);
conn->active = 0;
list_del(&conn->conn_list);
spin_unlock_irqrestore(&connlock, flags);
if (transport->destroy_conn)
transport->destroy_conn(conn);
return 0;
}
static int
iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev)
{
char *data = (char*)ev + sizeof(*ev);
struct iscsi_cls_conn *conn;
struct iscsi_cls_session *session;
int err = 0, value = 0;
session = iscsi_session_lookup(ev->u.set_param.sid);
conn = iscsi_conn_lookup(ev->u.set_param.sid, ev->u.set_param.cid);
if (!conn || !session)
return -EINVAL;
switch (ev->u.set_param.param) {
case ISCSI_PARAM_SESS_RECOVERY_TMO:
sscanf(data, "%d", &value);
if (value != 0)
session->recovery_tmo = value;
break;
default:
err = transport->set_param(conn, ev->u.set_param.param,
data, ev->u.set_param.len);
}
return err;
}
static int
iscsi_if_transport_ep(struct iscsi_transport *transport,
struct iscsi_uevent *ev, int msg_type)
{
struct sockaddr *dst_addr;
int rc = 0;
switch (msg_type) {
case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
if (!transport->ep_connect)
return -EINVAL;
dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
rc = transport->ep_connect(dst_addr,
ev->u.ep_connect.non_blocking,
&ev->r.ep_connect_ret.handle);
break;
case ISCSI_UEVENT_TRANSPORT_EP_POLL:
if (!transport->ep_poll)
return -EINVAL;
ev->r.retcode = transport->ep_poll(ev->u.ep_poll.ep_handle,
ev->u.ep_poll.timeout_ms);
break;
case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
if (!transport->ep_disconnect)
return -EINVAL;
transport->ep_disconnect(ev->u.ep_disconnect.ep_handle);
break;
}
return rc;
}
static int
iscsi_tgt_dscvr(struct iscsi_transport *transport,
struct iscsi_uevent *ev)
{
struct sockaddr *dst_addr;
if (!transport->tgt_dscvr)
return -EINVAL;
dst_addr = (struct sockaddr *)((char*)ev + sizeof(*ev));
return transport->tgt_dscvr(ev->u.tgt_dscvr.type,
ev->u.tgt_dscvr.host_no,
ev->u.tgt_dscvr.enable, dst_addr);
}
static int
iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
{
int err = 0;
struct iscsi_uevent *ev = NLMSG_DATA(nlh);
struct iscsi_transport *transport = NULL;
struct iscsi_internal *priv;
struct iscsi_cls_session *session;
struct iscsi_cls_conn *conn;
unsigned long flags;
priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
if (!priv)
return -EINVAL;
transport = priv->iscsi_transport;
if (!try_module_get(transport->owner))
return -EINVAL;
priv->daemon_pid = NETLINK_CREDS(skb)->pid;
switch (nlh->nlmsg_type) {
case ISCSI_UEVENT_CREATE_SESSION:
err = iscsi_if_create_session(priv, ev);
break;
case ISCSI_UEVENT_DESTROY_SESSION:
session = iscsi_session_lookup(ev->u.d_session.sid);
if (session) {
spin_lock_irqsave(&sesslock, flags);
list_del(&session->sess_list);
spin_unlock_irqrestore(&sesslock, flags);
transport->destroy_session(session);
} else
err = -EINVAL;
break;
case ISCSI_UEVENT_CREATE_CONN:
err = iscsi_if_create_conn(transport, ev);
break;
case ISCSI_UEVENT_DESTROY_CONN:
err = iscsi_if_destroy_conn(transport, ev);
break;
case ISCSI_UEVENT_BIND_CONN:
session = iscsi_session_lookup(ev->u.b_conn.sid);
conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid);
if (session && conn)
ev->r.retcode = transport->bind_conn(session, conn,
ev->u.b_conn.transport_eph,
ev->u.b_conn.is_leading);
else
err = -EINVAL;
break;
case ISCSI_UEVENT_SET_PARAM:
err = iscsi_set_param(transport, ev);
break;
case ISCSI_UEVENT_START_CONN:
conn = iscsi_conn_lookup(ev->u.start_conn.sid, ev->u.start_conn.cid);
if (conn)
ev->r.retcode = transport->start_conn(conn);
else
err = -EINVAL;
break;
case ISCSI_UEVENT_STOP_CONN:
conn = iscsi_conn_lookup(ev->u.stop_conn.sid, ev->u.stop_conn.cid);
if (conn)
transport->stop_conn(conn, ev->u.stop_conn.flag);
else
err = -EINVAL;
break;
case ISCSI_UEVENT_SEND_PDU:
conn = iscsi_conn_lookup(ev->u.send_pdu.sid, ev->u.send_pdu.cid);
if (conn)
ev->r.retcode = transport->send_pdu(conn,
(struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
(char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
ev->u.send_pdu.data_size);
else
err = -EINVAL;
break;
case ISCSI_UEVENT_GET_STATS:
err = iscsi_if_get_stats(transport, nlh);
break;
case ISCSI_UEVENT_TRANSPORT_EP_CONNECT:
case ISCSI_UEVENT_TRANSPORT_EP_POLL:
case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT:
err = iscsi_if_transport_ep(transport, ev, nlh->nlmsg_type);
break;
case ISCSI_UEVENT_TGT_DSCVR:
err = iscsi_tgt_dscvr(transport, ev);
break;
default:
err = -EINVAL;
break;
}
module_put(transport->owner);
return err;
}
/*
* Get message from skb (based on rtnetlink_rcv_skb). Each message is
* processed by iscsi_if_recv_msg. Malformed skbs with wrong lengths or
* invalid creds are discarded silently.
*/
static void
iscsi_if_rx(struct sock *sk, int len)
{
struct sk_buff *skb;
mutex_lock(&rx_queue_mutex);
while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
if (NETLINK_CREDS(skb)->uid) {
skb_pull(skb, skb->len);
goto free_skb;
}
while (skb->len >= NLMSG_SPACE(0)) {
int err;
uint32_t rlen;
struct nlmsghdr *nlh;
struct iscsi_uevent *ev;
nlh = (struct nlmsghdr *)skb->data;
if (nlh->nlmsg_len < sizeof(*nlh) ||
skb->len < nlh->nlmsg_len) {
break;
}
ev = NLMSG_DATA(nlh);
rlen = NLMSG_ALIGN(nlh->nlmsg_len);
if (rlen > skb->len)
rlen = skb->len;
err = iscsi_if_recv_msg(skb, nlh);
if (err) {
ev->type = ISCSI_KEVENT_IF_ERROR;
ev->iferror = err;
}
do {
/*
* special case for GET_STATS:
* on success - sending reply and stats from
* inside of if_recv_msg(),
* on error - fall through.
*/
if (ev->type == ISCSI_UEVENT_GET_STATS && !err)
break;
err = iscsi_if_send_reply(
NETLINK_CREDS(skb)->pid, nlh->nlmsg_seq,
nlh->nlmsg_type, 0, 0, ev, sizeof(*ev));
} while (err < 0 && err != -ECONNREFUSED);
skb_pull(skb, rlen);
}
free_skb:
kfree_skb(skb);
}
mutex_unlock(&rx_queue_mutex);
}
#define iscsi_cdev_to_conn(_cdev) \
iscsi_dev_to_conn(_cdev->dev)
#define ISCSI_CLASS_ATTR(_prefix,_name,_mode,_show,_store) \
struct class_device_attribute class_device_attr_##_prefix##_##_name = \
__ATTR(_name,_mode,_show,_store)
/*
* iSCSI connection attrs
*/
#define iscsi_conn_attr_show(param) \
static ssize_t \
show_conn_param_##param(struct class_device *cdev, char *buf) \
{ \
struct iscsi_cls_conn *conn = iscsi_cdev_to_conn(cdev); \
struct iscsi_transport *t = conn->transport; \
return t->get_conn_param(conn, param, buf); \
}
#define iscsi_conn_attr(field, param) \
iscsi_conn_attr_show(param) \
static ISCSI_CLASS_ATTR(conn, field, S_IRUGO, show_conn_param_##param, \
NULL);
iscsi_conn_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH);
iscsi_conn_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
iscsi_conn_attr(header_digest, ISCSI_PARAM_HDRDGST_EN);
iscsi_conn_attr(data_digest, ISCSI_PARAM_DATADGST_EN);
iscsi_conn_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN);
iscsi_conn_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN);
iscsi_conn_attr(persistent_port, ISCSI_PARAM_PERSISTENT_PORT);
iscsi_conn_attr(port, ISCSI_PARAM_CONN_PORT);
iscsi_conn_attr(exp_statsn, ISCSI_PARAM_EXP_STATSN);
iscsi_conn_attr(persistent_address, ISCSI_PARAM_PERSISTENT_ADDRESS);
iscsi_conn_attr(address, ISCSI_PARAM_CONN_ADDRESS);
#define iscsi_cdev_to_session(_cdev) \
iscsi_dev_to_session(_cdev->dev)
/*
* iSCSI session attrs
*/
#define iscsi_session_attr_show(param) \
static ssize_t \
show_session_param_##param(struct class_device *cdev, char *buf) \
{ \
struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev); \
struct iscsi_transport *t = session->transport; \
return t->get_session_param(session, param, buf); \
}
#define iscsi_session_attr(field, param) \
iscsi_session_attr_show(param) \
static ISCSI_CLASS_ATTR(sess, field, S_IRUGO, show_session_param_##param, \
NULL);
iscsi_session_attr(targetname, ISCSI_PARAM_TARGET_NAME);
iscsi_session_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN);
iscsi_session_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T);
iscsi_session_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN);
iscsi_session_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST);
iscsi_session_attr(max_burst_len, ISCSI_PARAM_MAX_BURST);
iscsi_session_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN);
iscsi_session_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN);
iscsi_session_attr(erl, ISCSI_PARAM_ERL);
iscsi_session_attr(tpgt, ISCSI_PARAM_TPGT);
#define iscsi_priv_session_attr_show(field, format) \
static ssize_t \
show_priv_session_##field(struct class_device *cdev, char *buf) \
{ \
struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev);\
return sprintf(buf, format"\n", session->field); \
}
#define iscsi_priv_session_attr(field, format) \
iscsi_priv_session_attr_show(field, format) \
static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO, show_priv_session_##field, \
NULL)
iscsi_priv_session_attr(recovery_tmo, "%d");
#define SETUP_PRIV_SESSION_RD_ATTR(field) \
do { \
priv->session_attrs[count] = &class_device_attr_priv_sess_##field; \
count++; \
} while (0)
#define SETUP_SESSION_RD_ATTR(field, param_flag) \
do { \
if (tt->param_mask & param_flag) { \
priv->session_attrs[count] = &class_device_attr_sess_##field; \
count++; \
} \
} while (0)
#define SETUP_CONN_RD_ATTR(field, param_flag) \
do { \
if (tt->param_mask & param_flag) { \
priv->conn_attrs[count] = &class_device_attr_conn_##field; \
count++; \
} \
} while (0)
static int iscsi_session_match(struct attribute_container *cont,
struct device *dev)
{
struct iscsi_cls_session *session;
struct Scsi_Host *shost;
struct iscsi_internal *priv;
if (!iscsi_is_session_dev(dev))
return 0;
session = iscsi_dev_to_session(dev);
shost = iscsi_session_to_shost(session);
if (!shost->transportt)
return 0;
priv = to_iscsi_internal(shost->transportt);
if (priv->session_cont.ac.class != &iscsi_session_class.class)
return 0;
return &priv->session_cont.ac == cont;
}
static int iscsi_conn_match(struct attribute_container *cont,
struct device *dev)
{
struct iscsi_cls_session *session;
struct iscsi_cls_conn *conn;
struct Scsi_Host *shost;
struct iscsi_internal *priv;
if (!iscsi_is_conn_dev(dev))
return 0;
conn = iscsi_dev_to_conn(dev);
session = iscsi_dev_to_session(conn->dev.parent);
shost = iscsi_session_to_shost(session);
if (!shost->transportt)
return 0;
priv = to_iscsi_internal(shost->transportt);
if (priv->conn_cont.ac.class != &iscsi_connection_class.class)
return 0;
return &priv->conn_cont.ac == cont;
}
static int iscsi_host_match(struct attribute_container *cont,
struct device *dev)
{
struct Scsi_Host *shost;
struct iscsi_internal *priv;
if (!scsi_is_host_device(dev))
return 0;
shost = dev_to_shost(dev);
if (!shost->transportt ||
shost->transportt->host_attrs.ac.class != &iscsi_host_class.class)
return 0;
priv = to_iscsi_internal(shost->transportt);
return &priv->t.host_attrs.ac == cont;
}
struct scsi_transport_template *
iscsi_register_transport(struct iscsi_transport *tt)
{
struct iscsi_internal *priv;
unsigned long flags;
int count = 0, err;
BUG_ON(!tt);
priv = iscsi_if_transport_lookup(tt);
if (priv)
return NULL;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return NULL;
INIT_LIST_HEAD(&priv->list);
priv->daemon_pid = -1;
priv->iscsi_transport = tt;
priv->t.user_scan = iscsi_user_scan;
priv->cdev.class = &iscsi_transport_class;
snprintf(priv->cdev.class_id, BUS_ID_SIZE, "%s", tt->name);
err = class_device_register(&priv->cdev);
if (err)
goto free_priv;
err = sysfs_create_group(&priv->cdev.kobj, &iscsi_transport_group);
if (err)
goto unregister_cdev;
/* host parameters */
priv->t.host_attrs.ac.attrs = &priv->host_attrs[0];
priv->t.host_attrs.ac.class = &iscsi_host_class.class;
priv->t.host_attrs.ac.match = iscsi_host_match;
priv->t.host_size = sizeof(struct iscsi_host);
priv->host_attrs[0] = NULL;
transport_container_register(&priv->t.host_attrs);
/* connection parameters */
priv->conn_cont.ac.attrs = &priv->conn_attrs[0];
priv->conn_cont.ac.class = &iscsi_connection_class.class;
priv->conn_cont.ac.match = iscsi_conn_match;
transport_container_register(&priv->conn_cont);
SETUP_CONN_RD_ATTR(max_recv_dlength, ISCSI_MAX_RECV_DLENGTH);
SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_MAX_XMIT_DLENGTH);
SETUP_CONN_RD_ATTR(header_digest, ISCSI_HDRDGST_EN);
SETUP_CONN_RD_ATTR(data_digest, ISCSI_DATADGST_EN);
SETUP_CONN_RD_ATTR(ifmarker, ISCSI_IFMARKER_EN);
SETUP_CONN_RD_ATTR(ofmarker, ISCSI_OFMARKER_EN);
SETUP_CONN_RD_ATTR(address, ISCSI_CONN_ADDRESS);
SETUP_CONN_RD_ATTR(port, ISCSI_CONN_PORT);
SETUP_CONN_RD_ATTR(exp_statsn, ISCSI_EXP_STATSN);
SETUP_CONN_RD_ATTR(persistent_address, ISCSI_PERSISTENT_ADDRESS);
SETUP_CONN_RD_ATTR(persistent_port, ISCSI_PERSISTENT_PORT);
BUG_ON(count > ISCSI_CONN_ATTRS);
priv->conn_attrs[count] = NULL;
count = 0;
/* session parameters */
priv->session_cont.ac.attrs = &priv->session_attrs[0];
priv->session_cont.ac.class = &iscsi_session_class.class;
priv->session_cont.ac.match = iscsi_session_match;
transport_container_register(&priv->session_cont);
SETUP_SESSION_RD_ATTR(initial_r2t, ISCSI_INITIAL_R2T_EN);
SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_MAX_R2T);
SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_IMM_DATA_EN);
SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_FIRST_BURST);
SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_MAX_BURST);
SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PDU_INORDER_EN);
SETUP_SESSION_RD_ATTR(data_seq_in_order, ISCSI_DATASEQ_INORDER_EN);
SETUP_SESSION_RD_ATTR(erl, ISCSI_ERL);
SETUP_SESSION_RD_ATTR(targetname, ISCSI_TARGET_NAME);
SETUP_SESSION_RD_ATTR(tpgt, ISCSI_TPGT);
SETUP_PRIV_SESSION_RD_ATTR(recovery_tmo);
BUG_ON(count > ISCSI_SESSION_ATTRS);
priv->session_attrs[count] = NULL;
spin_lock_irqsave(&iscsi_transport_lock, flags);
list_add(&priv->list, &iscsi_transports);
spin_unlock_irqrestore(&iscsi_transport_lock, flags);
printk(KERN_NOTICE "iscsi: registered transport (%s)\n", tt->name);
return &priv->t;
unregister_cdev:
class_device_unregister(&priv->cdev);
free_priv:
kfree(priv);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_register_transport);
int iscsi_unregister_transport(struct iscsi_transport *tt)
{
struct iscsi_internal *priv;
unsigned long flags;
BUG_ON(!tt);
mutex_lock(&rx_queue_mutex);
priv = iscsi_if_transport_lookup(tt);
BUG_ON (!priv);
spin_lock_irqsave(&iscsi_transport_lock, flags);
list_del(&priv->list);
spin_unlock_irqrestore(&iscsi_transport_lock, flags);
transport_container_unregister(&priv->conn_cont);
transport_container_unregister(&priv->session_cont);
transport_container_unregister(&priv->t.host_attrs);
sysfs_remove_group(&priv->cdev.kobj, &iscsi_transport_group);
class_device_unregister(&priv->cdev);
mutex_unlock(&rx_queue_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
static __init int iscsi_transport_init(void)
{
int err;
printk(KERN_INFO "Loading iSCSI transport class v%s.",
ISCSI_TRANSPORT_VERSION);
err = class_register(&iscsi_transport_class);
if (err)
return err;
err = transport_class_register(&iscsi_host_class);
if (err)
goto unregister_transport_class;
err = transport_class_register(&iscsi_connection_class);
if (err)
goto unregister_host_class;
err = transport_class_register(&iscsi_session_class);
if (err)
goto unregister_conn_class;
nls = netlink_kernel_create(NETLINK_ISCSI, 1, iscsi_if_rx,
THIS_MODULE);
if (!nls) {
err = -ENOBUFS;
goto unregister_session_class;
}
return 0;
unregister_session_class:
transport_class_unregister(&iscsi_session_class);
unregister_conn_class:
transport_class_unregister(&iscsi_connection_class);
unregister_host_class:
transport_class_unregister(&iscsi_host_class);
unregister_transport_class:
class_unregister(&iscsi_transport_class);
return err;
}
static void __exit iscsi_transport_exit(void)
{
sock_release(nls->sk_socket);
transport_class_unregister(&iscsi_connection_class);
transport_class_unregister(&iscsi_session_class);
transport_class_unregister(&iscsi_host_class);
class_unregister(&iscsi_transport_class);
}
module_init(iscsi_transport_init);
module_exit(iscsi_transport_exit);
MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
"Dmitry Yusupov <dmitry_yus@yahoo.com>, "
"Alex Aizman <itn780@yahoo.com>");
MODULE_DESCRIPTION("iSCSI Transport Interface");
MODULE_LICENSE("GPL");
MODULE_VERSION(ISCSI_TRANSPORT_VERSION);