[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/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 780bfcc..d07d309 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -146,7 +146,7 @@
 	spin_unlock_irqrestore(&session->lock, flags);
 	set_bit(SUSPEND_BIT, &conn->suspend_tx);
 	set_bit(SUSPEND_BIT, &conn->suspend_rx);
-	iscsi_conn_error(iscsi_handle(conn), err);
+	iscsi_conn_error(conn->cls_conn, err);
 }
 
 static inline int
@@ -689,7 +689,7 @@
 				break;
 
 			if (!conn->in.datalen) {
-				rc = iscsi_recv_pdu(iscsi_handle(conn), hdr,
+				rc = iscsi_recv_pdu(conn->cls_conn, hdr,
 						    NULL, 0);
 				if (conn->login_mtask != mtask) {
 					spin_lock(&session->lock);
@@ -737,7 +737,7 @@
 			if (!conn->in.datalen) {
 				struct iscsi_mgmt_task *mtask;
 
-				rc = iscsi_recv_pdu(iscsi_handle(conn), hdr,
+				rc = iscsi_recv_pdu(conn->cls_conn, hdr,
 						    NULL, 0);
 				mtask = (struct iscsi_mgmt_task *)
 					session->mgmt_cmds[conn->in.itt -
@@ -761,7 +761,7 @@
 				rc = iscsi_check_assign_cmdsn(session,
 						 (struct iscsi_nopin*)hdr);
 				if (!rc && hdr->ttt != ISCSI_RESERVED_TAG)
-					rc = iscsi_recv_pdu(iscsi_handle(conn),
+					rc = iscsi_recv_pdu(conn->cls_conn,
 							    hdr, NULL, 0);
 			} else
 				rc = ISCSI_ERR_PROTO;
@@ -1044,7 +1044,7 @@
 			goto exit;
 		}
 
-		rc = iscsi_recv_pdu(iscsi_handle(conn), conn->in.hdr,
+		rc = iscsi_recv_pdu(conn->cls_conn, conn->in.hdr,
 				    conn->data, conn->in.datalen);
 
 		if (!rc && conn->datadgst_en &&
@@ -2428,19 +2428,20 @@
 }
 
 static struct iscsi_cls_conn *
-iscsi_conn_create(struct Scsi_Host *shost, uint32_t conn_idx)
+iscsi_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
 {
+	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 	struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
 	struct iscsi_conn *conn;
 	struct iscsi_cls_conn *cls_conn;
 
-	cls_conn = iscsi_create_conn(hostdata_session(shost->hostdata),
-				     conn_idx);
+	cls_conn = iscsi_create_conn(cls_session, conn_idx);
 	if (!cls_conn)
 		return NULL;
 	conn = cls_conn->dd_data;
+	memset(conn, 0, sizeof(*conn));
 
-	memset(conn, 0, sizeof(struct iscsi_conn));
+	conn->cls_conn = cls_conn;
 	conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
 	conn->in_progress = IN_PROGRESS_WAIT_HEADER;
 	conn->id = conn_idx;
@@ -2625,11 +2626,13 @@
 }
 
 static int
-iscsi_conn_bind(iscsi_sessionh_t sessionh, iscsi_connh_t connh,
-		uint32_t transport_fd, int is_leading)
+iscsi_conn_bind(struct iscsi_cls_session *cls_session,
+		struct iscsi_cls_conn *cls_conn, uint32_t transport_fd,
+		int is_leading)
 {
-	struct iscsi_session *session = iscsi_ptr(sessionh);
-	struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = iscsi_ptr(connh);
+	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
+	struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
+	struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = cls_conn->dd_data;
 	struct sock *sk;
 	struct socket *sock;
 	int err;
@@ -2703,9 +2706,9 @@
 }
 
 static int
-iscsi_conn_start(iscsi_connh_t connh)
+iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
 {
-	struct iscsi_conn *conn = iscsi_ptr(connh);
+	struct iscsi_conn *conn = cls_conn->dd_data;
 	struct iscsi_session *session = conn->session;
 	struct sock *sk;
 
@@ -2754,9 +2757,9 @@
 }
 
 static void
-iscsi_conn_stop(iscsi_connh_t connh, int flag)
+iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
 {
-	struct iscsi_conn *conn = iscsi_ptr(connh);
+	struct iscsi_conn *conn = cls_conn->dd_data;
 	struct iscsi_session *session = conn->session;
 	struct sock *sk;
 	unsigned long flags;
@@ -3253,9 +3256,9 @@
 
 static struct iscsi_transport iscsi_tcp_transport;
 
-static struct Scsi_Host *
+static struct iscsi_cls_session *
 iscsi_session_create(struct scsi_transport_template *scsit,
-		     uint32_t initial_cmdsn)
+		     uint32_t initial_cmdsn, uint32_t *sid)
 {
 	struct Scsi_Host *shost;
 	struct iscsi_session *session;
@@ -3275,6 +3278,7 @@
 	session->exp_cmdsn = initial_cmdsn + 1;
 	session->max_cmdsn = initial_cmdsn + 1;
 	session->max_r2t = 1;
+	*sid = shost->host_no;
 
 	/* initialize SCSI PDU commands pool */
 	if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
@@ -3311,7 +3315,7 @@
 	if (iscsi_r2tpool_alloc(session))
 		goto r2tpool_alloc_fail;
 
-	return shost;
+	return hostdata_session(shost->hostdata);
 
 r2tpool_alloc_fail:
 	for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++)
@@ -3321,12 +3325,14 @@
 mgmtpool_alloc_fail:
 	iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
 cmdpool_alloc_fail:
+	iscsi_transport_destroy_session(shost);
 	return NULL;
 }
 
 static void
-iscsi_session_destroy(struct Scsi_Host *shost)
+iscsi_session_destroy(struct iscsi_cls_session *cls_session)
 {
+	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 	struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
 	int cmd_i;
 	struct iscsi_data_task *dtask, *n;
@@ -3350,10 +3356,10 @@
 }
 
 static int
-iscsi_conn_set_param(iscsi_connh_t connh, enum iscsi_param param,
+iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
 		     uint32_t value)
 {
-	struct iscsi_conn *conn = iscsi_ptr(connh);
+	struct iscsi_conn *conn = cls_conn->dd_data;
 	struct iscsi_session *session = conn->session;
 
 	spin_lock_bh(&session->lock);
@@ -3495,9 +3501,10 @@
 }
 
 static int
-iscsi_session_get_param(struct Scsi_Host *shost,
+iscsi_session_get_param(struct iscsi_cls_session *cls_session,
 			enum iscsi_param param, uint32_t *value)
 {
+	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 	struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
 
 	switch(param) {
@@ -3539,9 +3546,10 @@
 }
 
 static int
-iscsi_conn_get_param(void *data, enum iscsi_param param, uint32_t *value)
+iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
+		     enum iscsi_param param, uint32_t *value)
 {
-	struct iscsi_conn *conn = data;
+	struct iscsi_conn *conn = cls_conn->dd_data;
 
 	switch(param) {
 	case ISCSI_PARAM_MAX_RECV_DLENGTH:
@@ -3564,9 +3572,9 @@
 }
 
 static void
-iscsi_conn_get_stats(iscsi_connh_t connh, struct iscsi_stats *stats)
+iscsi_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
 {
-	struct iscsi_conn *conn = iscsi_ptr(connh);
+	struct iscsi_conn *conn = cls_conn->dd_data;
 
 	stats->txdata_octets = conn->txdata_octets;
 	stats->rxdata_octets = conn->rxdata_octets;
@@ -3587,10 +3595,10 @@
 }
 
 static int
-iscsi_conn_send_pdu(iscsi_connh_t connh, struct iscsi_hdr *hdr, char *data,
-		    uint32_t data_size)
+iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
+		    char *data, uint32_t data_size)
 {
-	struct iscsi_conn *conn = iscsi_ptr(connh);
+	struct iscsi_conn *conn = cls_conn->dd_data;
 	int rc;
 
 	mutex_lock(&conn->xmitmutex);