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linux_old1/drivers/scsi/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/mempool.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 8
#define ISCSI_CONN_ATTRS 6
struct iscsi_internal {
struct scsi_transport_template t;
struct iscsi_transport *iscsi_transport;
struct list_head list;
/*
* List of sessions for this transport
*/
struct list_head sessions;
/*
* based on transport capabilities, at register time we set these
* bits to tell the transport class it wants attributes displayed
* in sysfs or that it can support different iSCSI Data-Path
* capabilities
*/
uint32_t param_mask;
struct class_device cdev;
/*
* We do not have any private or other attrs.
*/
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];
};
/*
* 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 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 int daemon_pid;
static DEFINE_MUTEX(rx_queue_mutex);
struct mempool_zone {
mempool_t *pool;
atomic_t allocated;
int size;
int hiwat;
struct list_head freequeue;
spinlock_t freelock;
};
static struct mempool_zone *z_reply;
/*
* Z_MAX_* - actual mempool size allocated at the mempool_zone_init() time
* Z_HIWAT_* - zone's high watermark when if_error bit will be set to -ENOMEM
* so daemon will notice OOM on NETLINK tranposrt level and will
* be able to predict or change operational behavior
*/
#define Z_MAX_REPLY 8
#define Z_HIWAT_REPLY 6
#define Z_MAX_PDU 8
#define Z_HIWAT_PDU 6
#define Z_MAX_ERROR 16
#define Z_HIWAT_ERROR 12
static LIST_HEAD(connlist);
static DEFINE_SPINLOCK(connlock);
/*
* 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 iscsi_transport *transport = session->transport;
struct Scsi_Host *shost;
shost = iscsi_session_to_shost(session);
scsi_host_put(shost);
kfree(session);
module_put(transport->owner);
}
static int iscsi_is_session_dev(const struct device *dev)
{
return dev->release == iscsi_session_release;
}
/**
* 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)
{
struct iscsi_cls_session *session;
int err;
if (!try_module_get(transport->owner))
return NULL;
session = kzalloc(sizeof(*session), GFP_KERNEL);
if (!session)
goto module_put;
session->transport = transport;
/* this is released in the dev's release function */
scsi_host_get(shost);
snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u", shost->host_no);
session->dev.parent = &shost->shost_gendev;
session->dev.release = iscsi_session_release;
err = device_register(&session->dev);
if (err) {
dev_printk(KERN_ERR, &session->dev, "iscsi: could not "
"register session's dev\n");
goto free_session;
}
transport_register_device(&session->dev);
return session;
free_session:
kfree(session);
module_put:
module_put(transport->owner);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_create_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)
{
transport_unregister_device(&session->dev);
device_unregister(&session->dev);
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.
**/
struct iscsi_cls_conn *
iscsi_create_conn(struct iscsi_cls_session *session, uint32_t cid)
{
struct iscsi_transport *transport = session->transport;
struct Scsi_Host *shost = iscsi_session_to_shost(session);
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;
/* 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",
shost->host_no, 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);
/*
* These functions are used only by software iscsi_transports
* which do not allocate and more their scsi_hosts since this
* is initiated from userspace.
*/
/*
* iSCSI Session's hostdata organization:
*
* *------------------* <== hostdata_session(host->hostdata)
* | ptr to class sess|
* |------------------| <== iscsi_hostdata(host->hostdata)
* | transport's data |
* *------------------*
*/
#define hostdata_privsize(_t) (sizeof(unsigned long) + _t->hostdata_size + \
_t->hostdata_size % sizeof(unsigned long))
#define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
/**
* iscsi_transport_create_session - create iscsi cls session and host
* scsit: scsi transport template
* transport: iscsi transport template
*
* This can be used by software iscsi_transports that allocate
* a session per scsi host.
**/
struct Scsi_Host *
iscsi_transport_create_session(struct scsi_transport_template *scsit,
struct iscsi_transport *transport)
{
struct iscsi_cls_session *session;
struct Scsi_Host *shost;
shost = scsi_host_alloc(transport->host_template,
hostdata_privsize(transport));
if (!shost) {
printk(KERN_ERR "iscsi: can not allocate SCSI host for "
"session\n");
return NULL;
}
shost->max_id = 1;
shost->max_channel = 0;
shost->max_lun = transport->max_lun;
shost->max_cmd_len = transport->max_cmd_len;
shost->transportt = scsit;
shost->transportt->create_work_queue = 1;
if (scsi_add_host(shost, NULL))
goto free_host;
session = iscsi_create_session(shost, transport);
if (!session)
goto remove_host;
*(unsigned long*)shost->hostdata = (unsigned long)session;
return shost;
remove_host:
scsi_remove_host(shost);
free_host:
scsi_host_put(shost);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_transport_create_session);
/**
* iscsi_transport_destroy_session - destroy session and scsi host
* shost: scsi host
*
* This can be used by software iscsi_transports that allocate
* a session per scsi host.
**/
int iscsi_transport_destroy_session(struct Scsi_Host *shost)
{
struct iscsi_cls_session *session;
scsi_remove_host(shost);
session = hostdata_session(shost->hostdata);
iscsi_destroy_session(session);
/* ref from host alloc */
scsi_host_put(shost);
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_transport_destroy_session);
/*
* iscsi interface functions
*/
static struct iscsi_cls_conn*
iscsi_if_find_conn(uint64_t key)
{
unsigned long flags;
struct iscsi_cls_conn *conn;
spin_lock_irqsave(&connlock, flags);
list_for_each_entry(conn, &connlist, conn_list)
if (conn->connh == key) {
spin_unlock_irqrestore(&connlock, flags);
return conn;
}
spin_unlock_irqrestore(&connlock, flags);
return NULL;
}
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 inline struct list_head *skb_to_lh(struct sk_buff *skb)
{
return (struct list_head *)&skb->cb;
}
static void*
mempool_zone_alloc_skb(unsigned int gfp_mask, void *pool_data)
{
struct mempool_zone *zone = pool_data;
return alloc_skb(zone->size, gfp_mask);
}
static void
mempool_zone_free_skb(void *element, void *pool_data)
{
kfree_skb(element);
}
static void
mempool_zone_complete(struct mempool_zone *zone)
{
unsigned long flags;
struct list_head *lh, *n;
spin_lock_irqsave(&zone->freelock, flags);
list_for_each_safe(lh, n, &zone->freequeue) {
struct sk_buff *skb = (struct sk_buff *)((char *)lh -
offsetof(struct sk_buff, cb));
if (!skb_shared(skb)) {
list_del(skb_to_lh(skb));
mempool_free(skb, zone->pool);
atomic_dec(&zone->allocated);
}
}
spin_unlock_irqrestore(&zone->freelock, flags);
}
static struct mempool_zone *
mempool_zone_init(unsigned max, unsigned size, unsigned hiwat)
{
struct mempool_zone *zp;
zp = kzalloc(sizeof(*zp), GFP_KERNEL);
if (!zp)
return NULL;
zp->pool = mempool_create(max, mempool_zone_alloc_skb,
mempool_zone_free_skb, zp);
if (!zp->pool) {
kfree(zp);
return NULL;
}
zp->size = size;
zp->hiwat = hiwat;
INIT_LIST_HEAD(&zp->freequeue);
spin_lock_init(&zp->freelock);
atomic_set(&zp->allocated, 0);
return zp;
}
static void mempool_zone_destroy(struct mempool_zone *zp)
{
mempool_destroy(zp->pool);
kfree(zp);
}
static struct sk_buff*
mempool_zone_get_skb(struct mempool_zone *zone)
{
struct sk_buff *skb;
skb = mempool_alloc(zone->pool, GFP_ATOMIC);
if (skb)
atomic_inc(&zone->allocated);
return skb;
}
static int
iscsi_unicast_skb(struct mempool_zone *zone, struct sk_buff *skb)
{
unsigned long flags;
int rc;
skb_get(skb);
rc = netlink_unicast(nls, skb, daemon_pid, MSG_DONTWAIT);
if (rc < 0) {
mempool_free(skb, zone->pool);
printk(KERN_ERR "iscsi: can not unicast skb (%d)\n", rc);
return rc;
}
spin_lock_irqsave(&zone->freelock, flags);
list_add(skb_to_lh(skb), &zone->freequeue);
spin_unlock_irqrestore(&zone->freelock, flags);
return 0;
}
int iscsi_recv_pdu(iscsi_connh_t connh, struct iscsi_hdr *hdr,
char *data, uint32_t data_size)
{
struct nlmsghdr *nlh;
struct sk_buff *skb;
struct iscsi_uevent *ev;
struct iscsi_cls_conn *conn;
char *pdu;
int len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct iscsi_hdr) +
data_size);
conn = iscsi_if_find_conn(connh);
BUG_ON(!conn);
mempool_zone_complete(conn->z_pdu);
skb = mempool_zone_get_skb(conn->z_pdu);
if (!skb) {
iscsi_conn_error(connh, ISCSI_ERR_CONN_FAILED);
dev_printk(KERN_ERR, &conn->dev, "iscsi: can not deliver "
"control PDU: OOM\n");
return -ENOMEM;
}
nlh = __nlmsg_put(skb, 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;
if (atomic_read(&conn->z_pdu->allocated) >= conn->z_pdu->hiwat)
ev->iferror = -ENOMEM;
ev->r.recv_req.conn_handle = connh;
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(conn->z_pdu, skb);
}
EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
void iscsi_conn_error(iscsi_connh_t connh, enum iscsi_err error)
{
struct nlmsghdr *nlh;
struct sk_buff *skb;
struct iscsi_uevent *ev;
struct iscsi_cls_conn *conn;
int len = NLMSG_SPACE(sizeof(*ev));
conn = iscsi_if_find_conn(connh);
BUG_ON(!conn);
mempool_zone_complete(conn->z_error);
skb = mempool_zone_get_skb(conn->z_error);
if (!skb) {
dev_printk(KERN_ERR, &conn->dev, "iscsi: gracefully ignored "
"conn error (%d)\n", error);
return;
}
nlh = __nlmsg_put(skb, 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;
if (atomic_read(&conn->z_error->allocated) >= conn->z_error->hiwat)
ev->iferror = -ENOMEM;
ev->r.connerror.error = error;
ev->r.connerror.conn_handle = connh;
iscsi_unicast_skb(conn->z_error, skb);
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;
mempool_zone_complete(z_reply);
skb = mempool_zone_get_skb(z_reply);
/*
* 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(z_reply, skb);
}
static int
iscsi_if_get_stats(struct iscsi_transport *transport, struct sk_buff *skb,
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;
int len = NLMSG_SPACE(sizeof(*ev) +
sizeof(struct iscsi_stats) +
sizeof(struct iscsi_stats_custom) *
ISCSI_STATS_CUSTOM_MAX);
int err = 0;
conn = iscsi_if_find_conn(ev->u.get_stats.conn_handle);
if (!conn)
return -EEXIST;
do {
int actual_size;
mempool_zone_complete(conn->z_pdu);
skbstat = mempool_zone_get_skb(conn->z_pdu);
if (!skbstat) {
dev_printk(KERN_ERR, &conn->dev, "iscsi: can not "
"deliver stats: OOM\n");
return -ENOMEM;
}
nlhstat = __nlmsg_put(skbstat, 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;
if (atomic_read(&conn->z_pdu->allocated) >= conn->z_pdu->hiwat)
evstat->iferror = -ENOMEM;
evstat->u.get_stats.conn_handle =
ev->u.get_stats.conn_handle;
stats = (struct iscsi_stats *)
((char*)evstat + sizeof(*evstat));
memset(stats, 0, sizeof(*stats));
transport->get_stats(ev->u.get_stats.conn_handle, 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(skb, NLMSG_ALIGN(actual_size));
nlhstat->nlmsg_len = actual_size;
err = iscsi_unicast_skb(conn->z_pdu, skbstat);
} while (err < 0 && err != -ECONNREFUSED);
return err;
}
static int
iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
{
struct iscsi_transport *transport = priv->iscsi_transport;
struct Scsi_Host *shost;
if (!transport->create_session)
return -EINVAL;
shost = transport->create_session(&priv->t,
ev->u.c_session.initial_cmdsn);
if (!shost)
return -ENOMEM;
ev->r.c_session_ret.session_handle = iscsi_handle(iscsi_hostdata(shost->hostdata));
ev->r.c_session_ret.sid = shost->host_no;
return 0;
}
static int
iscsi_if_destroy_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
{
struct iscsi_transport *transport = priv->iscsi_transport;
struct Scsi_Host *shost;
if (!transport->destroy_session)
return -EINVAL;
shost = scsi_host_lookup(ev->u.d_session.sid);
if (shost == ERR_PTR(-ENXIO))
return -EEXIST;
if (transport->destroy_session)
transport->destroy_session(shost);
/* ref from host lookup */
scsi_host_put(shost);
return 0;
}
static int
iscsi_if_create_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev){
struct Scsi_Host *shost;
struct iscsi_cls_conn *conn;
unsigned long flags;
if (!transport->create_conn)
return -EINVAL;
shost = scsi_host_lookup(ev->u.c_conn.sid);
if (shost == ERR_PTR(-ENXIO))
return -EEXIST;
conn = transport->create_conn(shost, ev->u.c_conn.cid);
if (!conn)
goto release_ref;
conn->z_pdu = mempool_zone_init(Z_MAX_PDU,
NLMSG_SPACE(sizeof(struct iscsi_uevent) +
sizeof(struct iscsi_hdr) +
DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH),
Z_HIWAT_PDU);
if (!conn->z_pdu) {
dev_printk(KERN_ERR, &conn->dev, "iscsi: can not allocate "
"pdu zone for new conn\n");
goto destroy_conn;
}
conn->z_error = mempool_zone_init(Z_MAX_ERROR,
NLMSG_SPACE(sizeof(struct iscsi_uevent)),
Z_HIWAT_ERROR);
if (!conn->z_error) {
dev_printk(KERN_ERR, &conn->dev, "iscsi: can not allocate "
"error zone for new conn\n");
goto free_pdu_pool;
}
ev->r.handle = conn->connh = iscsi_handle(conn->dd_data);
spin_lock_irqsave(&connlock, flags);
list_add(&conn->conn_list, &connlist);
conn->active = 1;
spin_unlock_irqrestore(&connlock, flags);
scsi_host_put(shost);
return 0;
free_pdu_pool:
mempool_zone_destroy(conn->z_pdu);
destroy_conn:
if (transport->destroy_conn)
transport->destroy_conn(conn->dd_data);
release_ref:
scsi_host_put(shost);
return -ENOMEM;
}
static int
iscsi_if_destroy_conn(struct iscsi_transport *transport, struct iscsi_uevent *ev)
{
unsigned long flags;
struct iscsi_cls_conn *conn;
struct mempool_zone *z_error, *z_pdu;
conn = iscsi_if_find_conn(ev->u.d_conn.conn_handle);
if (!conn)
return -EEXIST;
if (!transport->destroy_conn)
return -EINVAL;
spin_lock_irqsave(&connlock, flags);
conn->active = 0;
list_del(&conn->conn_list);
spin_unlock_irqrestore(&connlock, flags);
z_pdu = conn->z_pdu;
z_error = conn->z_error;
if (transport->destroy_conn)
transport->destroy_conn(conn);
mempool_zone_destroy(z_pdu);
mempool_zone_destroy(z_error);
return 0;
}
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;
if (NETLINK_CREDS(skb)->uid)
return -EPERM;
priv = iscsi_if_transport_lookup(iscsi_ptr(ev->transport_handle));
if (!priv)
return -EINVAL;
transport = priv->iscsi_transport;
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:
err = iscsi_if_destroy_session(priv, ev);
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:
if (!iscsi_if_find_conn(ev->u.b_conn.conn_handle))
return -EEXIST;
ev->r.retcode = transport->bind_conn(
ev->u.b_conn.session_handle,
ev->u.b_conn.conn_handle,
ev->u.b_conn.transport_fd,
ev->u.b_conn.is_leading);
break;
case ISCSI_UEVENT_SET_PARAM:
if (!iscsi_if_find_conn(ev->u.set_param.conn_handle))
return -EEXIST;
ev->r.retcode = transport->set_param(
ev->u.set_param.conn_handle,
ev->u.set_param.param, ev->u.set_param.value);
break;
case ISCSI_UEVENT_START_CONN:
if (!iscsi_if_find_conn(ev->u.start_conn.conn_handle))
return -EEXIST;
ev->r.retcode = transport->start_conn(
ev->u.start_conn.conn_handle);
break;
case ISCSI_UEVENT_STOP_CONN:
if (!iscsi_if_find_conn(ev->u.stop_conn.conn_handle))
return -EEXIST;
transport->stop_conn(ev->u.stop_conn.conn_handle,
ev->u.stop_conn.flag);
break;
case ISCSI_UEVENT_SEND_PDU:
if (!iscsi_if_find_conn(ev->u.send_pdu.conn_handle))
return -EEXIST;
ev->r.retcode = transport->send_pdu(
ev->u.send_pdu.conn_handle,
(struct iscsi_hdr*)((char*)ev + sizeof(*ev)),
(char*)ev + sizeof(*ev) + ev->u.send_pdu.hdr_size,
ev->u.send_pdu.data_size);
break;
case ISCSI_UEVENT_GET_STATS:
err = iscsi_if_get_stats(transport, skb, nlh);
break;
default:
err = -EINVAL;
break;
}
return err;
}
/* Get message from skb (based on rtnetlink_rcv_skb). Each message is
* processed by iscsi_if_recv_msg. Malformed skbs with wrong length 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) {
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));
if (atomic_read(&z_reply->allocated) >=
z_reply->hiwat)
ev->iferror = -ENOMEM;
} while (err < 0 && err != -ECONNREFUSED);
skb_pull(skb, rlen);
}
kfree_skb(skb);
}
mutex_unlock(&rx_queue_mutex);
}
#define iscsi_cdev_to_conn(_cdev) \
iscsi_dev_to_conn(_cdev->dev)
/*
* iSCSI connection attrs
*/
#define iscsi_conn_int_attr_show(param, format) \
static ssize_t \
show_conn_int_param_##param(struct class_device *cdev, char *buf) \
{ \
uint32_t value = 0; \
struct iscsi_cls_conn *conn = iscsi_cdev_to_conn(cdev); \
struct iscsi_transport *t = conn->transport; \
\
t->get_conn_param(conn->dd_data, param, &value); \
return snprintf(buf, 20, format"\n", value); \
}
#define iscsi_conn_int_attr(field, param, format) \
iscsi_conn_int_attr_show(param, format) \
static CLASS_DEVICE_ATTR(field, S_IRUGO, show_conn_int_param_##param, NULL);
iscsi_conn_int_attr(max_recv_dlength, ISCSI_PARAM_MAX_RECV_DLENGTH, "%u");
iscsi_conn_int_attr(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH, "%u");
iscsi_conn_int_attr(header_digest, ISCSI_PARAM_HDRDGST_EN, "%d");
iscsi_conn_int_attr(data_digest, ISCSI_PARAM_DATADGST_EN, "%d");
iscsi_conn_int_attr(ifmarker, ISCSI_PARAM_IFMARKER_EN, "%d");
iscsi_conn_int_attr(ofmarker, ISCSI_PARAM_OFMARKER_EN, "%d");
#define iscsi_cdev_to_session(_cdev) \
iscsi_dev_to_session(_cdev->dev)
/*
* iSCSI session attrs
*/
#define iscsi_session_int_attr_show(param, format) \
static ssize_t \
show_session_int_param_##param(struct class_device *cdev, char *buf) \
{ \
uint32_t value = 0; \
struct iscsi_cls_session *session = iscsi_cdev_to_session(cdev); \
struct Scsi_Host *shost = iscsi_session_to_shost(session); \
struct iscsi_transport *t = session->transport; \
\
t->get_session_param(shost, param, &value); \
return snprintf(buf, 20, format"\n", value); \
}
#define iscsi_session_int_attr(field, param, format) \
iscsi_session_int_attr_show(param, format) \
static CLASS_DEVICE_ATTR(field, S_IRUGO, show_session_int_param_##param, NULL);
iscsi_session_int_attr(initial_r2t, ISCSI_PARAM_INITIAL_R2T_EN, "%d");
iscsi_session_int_attr(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T, "%hu");
iscsi_session_int_attr(immediate_data, ISCSI_PARAM_IMM_DATA_EN, "%d");
iscsi_session_int_attr(first_burst_len, ISCSI_PARAM_FIRST_BURST, "%u");
iscsi_session_int_attr(max_burst_len, ISCSI_PARAM_MAX_BURST, "%u");
iscsi_session_int_attr(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN, "%d");
iscsi_session_int_attr(data_seq_in_order, ISCSI_PARAM_DATASEQ_INORDER_EN, "%d");
iscsi_session_int_attr(erl, ISCSI_PARAM_ERL, "%d");
#define SETUP_SESSION_RD_ATTR(field, param) \
if (priv->param_mask & (1 << param)) { \
priv->session_attrs[count] = &class_device_attr_##field;\
count++; \
}
#define SETUP_CONN_RD_ATTR(field, param) \
if (priv->param_mask & (1 << param)) { \
priv->conn_attrs[count] = &class_device_attr_##field; \
count++; \
}
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;
}
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 = kmalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return NULL;
memset(priv, 0, sizeof(*priv));
INIT_LIST_HEAD(&priv->list);
INIT_LIST_HEAD(&priv->sessions);
priv->iscsi_transport = tt;
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;
/* setup parameters mask */
priv->param_mask = 0xFFFFFFFF;
if (!(tt->caps & CAP_MULTI_R2T))
priv->param_mask &= ~(1 << ISCSI_PARAM_MAX_R2T);
if (!(tt->caps & CAP_HDRDGST))
priv->param_mask &= ~(1 << ISCSI_PARAM_HDRDGST_EN);
if (!(tt->caps & CAP_DATADGST))
priv->param_mask &= ~(1 << ISCSI_PARAM_DATADGST_EN);
if (!(tt->caps & CAP_MARKERS)) {
priv->param_mask &= ~(1 << ISCSI_PARAM_IFMARKER_EN);
priv->param_mask &= ~(1 << ISCSI_PARAM_OFMARKER_EN);
}
/* 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_PARAM_MAX_RECV_DLENGTH);
SETUP_CONN_RD_ATTR(max_xmit_dlength, ISCSI_PARAM_MAX_XMIT_DLENGTH);
SETUP_CONN_RD_ATTR(header_digest, ISCSI_PARAM_HDRDGST_EN);
SETUP_CONN_RD_ATTR(data_digest, ISCSI_PARAM_DATADGST_EN);
SETUP_CONN_RD_ATTR(ifmarker, ISCSI_PARAM_IFMARKER_EN);
SETUP_CONN_RD_ATTR(ofmarker, ISCSI_PARAM_OFMARKER_EN);
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_PARAM_INITIAL_R2T_EN);
SETUP_SESSION_RD_ATTR(max_outstanding_r2t, ISCSI_PARAM_MAX_R2T);
SETUP_SESSION_RD_ATTR(immediate_data, ISCSI_PARAM_IMM_DATA_EN);
SETUP_SESSION_RD_ATTR(first_burst_len, ISCSI_PARAM_FIRST_BURST);
SETUP_SESSION_RD_ATTR(max_burst_len, ISCSI_PARAM_MAX_BURST);
SETUP_SESSION_RD_ATTR(data_pdu_in_order, ISCSI_PARAM_PDU_INORDER_EN);
SETUP_SESSION_RD_ATTR(data_seq_in_order,ISCSI_PARAM_DATASEQ_INORDER_EN)
SETUP_SESSION_RD_ATTR(erl, ISCSI_PARAM_ERL);
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);
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 int
iscsi_rcv_nl_event(struct notifier_block *this, unsigned long event, void *ptr)
{
struct netlink_notify *n = ptr;
if (event == NETLINK_URELEASE &&
n->protocol == NETLINK_ISCSI && n->pid) {
struct iscsi_cls_conn *conn;
unsigned long flags;
mempool_zone_complete(z_reply);
spin_lock_irqsave(&connlock, flags);
list_for_each_entry(conn, &connlist, conn_list) {
mempool_zone_complete(conn->z_error);
mempool_zone_complete(conn->z_pdu);
}
spin_unlock_irqrestore(&connlock, flags);
}
return NOTIFY_DONE;
}
static struct notifier_block iscsi_nl_notifier = {
.notifier_call = iscsi_rcv_nl_event,
};
static __init int iscsi_transport_init(void)
{
int err;
err = class_register(&iscsi_transport_class);
if (err)
return err;
err = transport_class_register(&iscsi_connection_class);
if (err)
goto unregister_transport_class;
err = transport_class_register(&iscsi_session_class);
if (err)
goto unregister_conn_class;
err = netlink_register_notifier(&iscsi_nl_notifier);
if (err)
goto unregister_session_class;
nls = netlink_kernel_create(NETLINK_ISCSI, 1, iscsi_if_rx,
THIS_MODULE);
if (!nls) {
err = -ENOBUFS;
goto unregister_notifier;
}
z_reply = mempool_zone_init(Z_MAX_REPLY,
NLMSG_SPACE(sizeof(struct iscsi_uevent)), Z_HIWAT_REPLY);
if (z_reply)
return 0;
sock_release(nls->sk_socket);
unregister_notifier:
netlink_unregister_notifier(&iscsi_nl_notifier);
unregister_session_class:
transport_class_unregister(&iscsi_session_class);
unregister_conn_class:
transport_class_unregister(&iscsi_connection_class);
unregister_transport_class:
class_unregister(&iscsi_transport_class);
return err;
}
static void __exit iscsi_transport_exit(void)
{
mempool_zone_destroy(z_reply);
sock_release(nls->sk_socket);
netlink_unregister_notifier(&iscsi_nl_notifier);
transport_class_unregister(&iscsi_connection_class);
transport_class_unregister(&iscsi_session_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");
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