[SCSI] iscsi update: cleanup iscsi class interface
From:
michaelc@cs.wisc.edu
fujita.tomonori@lab.ntt.co.jp
da-x@monatomic.org
and err path fixup from:
ogerlitz@voltaire.com
This patch cleans up that interface by having the lld and class
pass a iscsi_cls_session or iscsi_cls_conn between each other when
the function is used by HW and SW iscsi llds. This way the lld
does not have to remember if it has to send a handle or pointer
and a handle or pointer to connection, session or host.
This also has the class verify the session handle that gets passed from
userspace instead of using the pointer passed into the kernel directly.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Alex Aizman <itn780@yahoo.com>
Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 59a1c9d..b618685 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -164,9 +164,43 @@
#define Z_MAX_ERROR 16
#define Z_HIWAT_ERROR 12
+static LIST_HEAD(sesslist);
+static DEFINE_SPINLOCK(sesslock);
static LIST_HEAD(connlist);
static DEFINE_SPINLOCK(connlock);
+static struct iscsi_cls_session *iscsi_session_lookup(uint64_t handle)
+{
+ unsigned long flags;
+ struct iscsi_cls_session *sess;
+
+ spin_lock_irqsave(&sesslock, flags);
+ list_for_each_entry(sess, &sesslist, sess_list) {
+ if (sess == iscsi_ptr(handle)) {
+ spin_unlock_irqrestore(&sesslock, flags);
+ return sess;
+ }
+ }
+ spin_unlock_irqrestore(&sesslock, flags);
+ return NULL;
+}
+
+static struct iscsi_cls_conn *iscsi_conn_lookup(uint64_t handle)
+{
+ unsigned long flags;
+ struct iscsi_cls_conn *conn;
+
+ spin_lock_irqsave(&connlock, flags);
+ list_for_each_entry(conn, &connlist, conn_list) {
+ if (conn == iscsi_ptr(handle)) {
+ 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
@@ -365,6 +399,7 @@
{
struct iscsi_cls_session *session;
struct Scsi_Host *shost;
+ unsigned long flags;
shost = scsi_host_alloc(transport->host_template,
hostdata_privsize(transport));
@@ -389,6 +424,9 @@
goto remove_host;
*(unsigned long*)shost->hostdata = (unsigned long)session;
+ spin_lock_irqsave(&sesslock, flags);
+ list_add(&session->sess_list, &sesslist);
+ spin_unlock_irqrestore(&sesslock, flags);
return shost;
remove_host:
@@ -410,9 +448,13 @@
int iscsi_transport_destroy_session(struct Scsi_Host *shost)
{
struct iscsi_cls_session *session;
+ unsigned long flags;
scsi_remove_host(shost);
session = hostdata_session(shost->hostdata);
+ spin_lock_irqsave(&sesslock, flags);
+ list_del(&session->sess_list);
+ spin_unlock_irqrestore(&sesslock, flags);
iscsi_destroy_session(session);
/* ref from host alloc */
scsi_host_put(shost);
@@ -424,22 +466,6 @@
/*
* 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)
{
@@ -559,25 +585,21 @@
return 0;
}
-int iscsi_recv_pdu(iscsi_connh_t connh, struct iscsi_hdr *hdr,
+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;
- 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);
+ iscsi_conn_error(conn, ISCSI_ERR_CONN_FAILED);
dev_printk(KERN_ERR, &conn->dev, "iscsi: can not deliver "
"control PDU: OOM\n");
return -ENOMEM;
@@ -590,7 +612,7 @@
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;
+ ev->r.recv_req.conn_handle = iscsi_handle(conn);
pdu = (char*)ev + sizeof(*ev);
memcpy(pdu, hdr, sizeof(struct iscsi_hdr));
memcpy(pdu + sizeof(struct iscsi_hdr), data, data_size);
@@ -599,17 +621,13 @@
}
EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
-void iscsi_conn_error(iscsi_connh_t connh, enum iscsi_err error)
+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_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);
@@ -626,7 +644,7 @@
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;
+ ev->r.connerror.conn_handle = iscsi_handle(conn);
iscsi_unicast_skb(conn->z_error, skb);
@@ -677,7 +695,7 @@
ISCSI_STATS_CUSTOM_MAX);
int err = 0;
- conn = iscsi_if_find_conn(ev->u.get_stats.conn_handle);
+ conn = iscsi_conn_lookup(ev->u.get_stats.conn_handle);
if (!conn)
return -EEXIST;
@@ -707,7 +725,7 @@
((char*)evstat + sizeof(*evstat));
memset(stats, 0, sizeof(*stats));
- transport->get_stats(ev->u.get_stats.conn_handle, stats);
+ transport->get_stats(conn, stats);
actual_size = NLMSG_SPACE(sizeof(struct iscsi_uevent) +
sizeof(struct iscsi_stats) +
sizeof(struct iscsi_stats_custom) *
@@ -727,58 +745,34 @@
iscsi_if_create_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
{
struct iscsi_transport *transport = priv->iscsi_transport;
- struct Scsi_Host *shost;
+ struct iscsi_cls_session *session;
+ uint32_t sid;
- if (!transport->create_session)
- return -EINVAL;
-
- shost = transport->create_session(&priv->t,
- ev->u.c_session.initial_cmdsn);
- if (!shost)
+ session = transport->create_session(&priv->t,
+ ev->u.c_session.initial_cmdsn,
+ &sid);
+ if (!session)
return -ENOMEM;
- ev->r.c_session_ret.session_handle = iscsi_handle(iscsi_hostdata(shost->hostdata));
- ev->r.c_session_ret.sid = shost->host_no;
+ ev->r.c_session_ret.session_handle = iscsi_handle(session);
+ ev->r.c_session_ret.sid = sid;
return 0;
}
static int
-iscsi_if_destroy_session(struct iscsi_internal *priv, struct iscsi_uevent *ev)
+iscsi_if_create_conn(struct iscsi_transport *transport, 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;
+ struct iscsi_cls_session *session;
unsigned long flags;
- if (!transport->create_conn)
+ session = iscsi_session_lookup(ev->u.c_conn.session_handle);
+ if (!session)
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);
+ conn = transport->create_conn(session, ev->u.c_conn.cid);
if (!conn)
- goto release_ref;
+ return -ENOMEM;
conn->z_pdu = mempool_zone_init(Z_MAX_PDU,
NLMSG_SPACE(sizeof(struct iscsi_uevent) +
@@ -800,14 +794,13 @@
goto free_pdu_pool;
}
- ev->r.handle = conn->connh = iscsi_handle(conn->dd_data);
+ ev->r.handle = iscsi_handle(conn);
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:
@@ -815,8 +808,6 @@
destroy_conn:
if (transport->destroy_conn)
transport->destroy_conn(conn->dd_data);
-release_ref:
- scsi_host_put(shost);
return -ENOMEM;
}
@@ -827,13 +818,9 @@
struct iscsi_cls_conn *conn;
struct mempool_zone *z_error, *z_pdu;
- conn = iscsi_if_find_conn(ev->u.d_conn.conn_handle);
+ conn = iscsi_conn_lookup(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);
@@ -858,6 +845,8 @@
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;
if (NETLINK_CREDS(skb)->uid)
return -EPERM;
@@ -867,6 +856,9 @@
return -EINVAL;
transport = priv->iscsi_transport;
+ if (!try_module_get(transport->owner))
+ return -EINVAL;
+
daemon_pid = NETLINK_CREDS(skb)->pid;
switch (nlh->nlmsg_type) {
@@ -874,7 +866,11 @@
err = iscsi_if_create_session(priv, ev);
break;
case ISCSI_UEVENT_DESTROY_SESSION:
- err = iscsi_if_destroy_session(priv, ev);
+ session = iscsi_session_lookup(ev->u.d_session.session_handle);
+ if (session)
+ transport->destroy_session(session);
+ else
+ err = -EINVAL;
break;
case ISCSI_UEVENT_CREATE_CONN:
err = iscsi_if_create_conn(transport, ev);
@@ -883,41 +879,48 @@
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);
+ session = iscsi_session_lookup(ev->u.b_conn.session_handle);
+ conn = iscsi_conn_lookup(ev->u.b_conn.conn_handle);
+
+ if (session && conn)
+ ev->r.retcode = transport->bind_conn(session, conn,
+ ev->u.b_conn.transport_fd,
+ ev->u.b_conn.is_leading);
+ else
+ err = -EINVAL;
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);
+ conn = iscsi_conn_lookup(ev->u.set_param.conn_handle);
+ if (conn)
+ ev->r.retcode = transport->set_param(conn,
+ ev->u.set_param.param, ev->u.set_param.value);
+ else
+ err = -EINVAL;
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);
+ conn = iscsi_conn_lookup(ev->u.start_conn.conn_handle);
+ if (conn)
+ ev->r.retcode = transport->start_conn(conn);
+ else
+ err = -EINVAL;
+
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);
+ conn = iscsi_conn_lookup(ev->u.stop_conn.conn_handle);
+ if (conn)
+ transport->stop_conn(conn, ev->u.stop_conn.flag);
+ else
+ err = -EINVAL;
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);
+ conn = iscsi_conn_lookup(ev->u.send_pdu.conn_handle);
+ 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, skb, nlh);
@@ -927,6 +930,7 @@
break;
}
+ module_put(transport->owner);
return err;
}
@@ -997,7 +1001,7 @@
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); \
+ t->get_conn_param(conn, param, &value); \
return snprintf(buf, 20, format"\n", value); \
}
@@ -1024,10 +1028,9 @@
{ \
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); \
+ t->get_session_param(session, param, &value); \
return snprintf(buf, 20, format"\n", value); \
}