iscsi update for scsi-post

iscsi update for scsi-post

[michaelc]

The following patches are fixes and enhancements for 2.6.28 scsi-post,
becuase:

Subject: [PATCH 6/7] libiscsi: check reason why we are stopping iscsi session to determine error value

collides with other patches in that tree.

[PATCH 1/7] libiscsi: fix data corruption when target has to resend data-in packets

[michaelc]

From: Mike Christie <michaelc@cs.wisc.edu>

iscsi_tcp was updating the exp_statsn (exp_statsn acknowledges
status and tells the target it is ok to let the resources for
a iscsi pdu to be reused) before it got all the data for pdu read
into OS buffers. Data corruption was occuring if something happens
to a packet and the network layer requests a retransmit, and the
initiator has told the target about the udpated exp_statsn ack,
then the target may be sending data from a buffer it has reused
for a new iscsi pdu. This fixes the problem by having the LLD
(iscsi_tcp in this case) just handle the transferring of data, and
has libiscsi handle the processing of status (libiscsi completion
processing is done after LLD data transfers are complete).

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
---
 drivers/scsi/iscsi_tcp.c |   29 +++++------------------------
 drivers/scsi/libiscsi.c  |   41 +++++++++++++++++++++++++++++++++++------
 2 files changed, 40 insertions(+), 30 deletions(-)

diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 2a2f009..e960f00 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -523,22 +523,20 @@ iscsi_tcp_cleanup_task(struct iscsi_conn *conn, struct iscsi_task *task)
 }
 
 /**
- * iscsi_data_rsp - SCSI Data-In Response processing
+ * iscsi_data_in - SCSI Data-In Response processing
  * @conn: iscsi connection
  * @task: scsi command task
  **/
 static int
-iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_task *task)
+iscsi_data_in(struct iscsi_conn *conn, struct iscsi_task *task)
 {
 	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
 	struct iscsi_tcp_task *tcp_task = task->dd_data;
 	struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)tcp_conn->in.hdr;
-	struct iscsi_session *session = conn->session;
-	struct scsi_cmnd *sc = task->sc;
 	int datasn = be32_to_cpu(rhdr->datasn);
-	unsigned total_in_length = scsi_in(sc)->length;
+	unsigned total_in_length = scsi_in(task->sc)->length;
 
-	iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
+	iscsi_update_cmdsn(conn->session, (struct iscsi_nopin*)rhdr);
 	if (tcp_conn->in.datalen == 0)
 		return 0;
 
@@ -558,23 +556,6 @@ iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_task *task)
 		return ISCSI_ERR_DATA_OFFSET;
 	}
 
-	if (rhdr->flags & ISCSI_FLAG_DATA_STATUS) {
-		sc->result = (DID_OK << 16) | rhdr->cmd_status;
-		conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
-		if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
-		                   ISCSI_FLAG_DATA_OVERFLOW)) {
-			int res_count = be32_to_cpu(rhdr->residual_count);
-
-			if (res_count > 0 &&
-			    (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
-			     res_count <= total_in_length))
-				scsi_in(sc)->resid = res_count;
-			else
-				sc->result = (DID_BAD_TARGET << 16) |
-					rhdr->cmd_status;
-		}
-	}
-
 	conn->datain_pdus_cnt++;
 	return 0;
 }
@@ -774,7 +755,7 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 		if (!task)
 			rc = ISCSI_ERR_BAD_ITT;
 		else
-			rc = iscsi_data_rsp(conn, task);
+			rc = iscsi_data_in(conn, task);
 		if (rc) {
 			spin_unlock(&conn->session->lock);
 			break;
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 0e8f26b..f9539af 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -633,6 +633,40 @@ out:
 	__iscsi_put_task(task);
 }
 
+/**
+ * iscsi_data_in_rsp - SCSI Data-In Response processing
+ * @conn: iscsi connection
+ * @hdr:  iscsi pdu
+ * @task: scsi command task
+ **/
+static void
+iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
+		  struct iscsi_task *task)
+{
+	struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
+	struct scsi_cmnd *sc = task->sc;
+
+	if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
+		return;
+
+	sc->result = (DID_OK << 16) | rhdr->cmd_status;
+	conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
+	if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
+	                   ISCSI_FLAG_DATA_OVERFLOW)) {
+		int res_count = be32_to_cpu(rhdr->residual_count);
+
+		if (res_count > 0 &&
+		    (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
+		     res_count <= scsi_in(sc)->length))
+			scsi_in(sc)->resid = res_count;
+		else
+			sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
+	}
+
+	conn->scsirsp_pdus_cnt++;
+	__iscsi_put_task(task);
+}
+
 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 {
 	struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
@@ -818,12 +852,7 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 		iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
 		break;
 	case ISCSI_OP_SCSI_DATA_IN:
-		if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
-			conn->scsirsp_pdus_cnt++;
-			iscsi_update_cmdsn(session,
-					   (struct iscsi_nopin*) hdr);
-			__iscsi_put_task(task);
-		}
+		iscsi_data_in_rsp(conn, hdr, task);
 		break;
 	case ISCSI_OP_LOGOUT_RSP:
 		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
-- 
1.5.4.1

[PATCH 2/7] libiscsi: Support drivers initiating session removal

[michaelc]

From: Mike Christie <michaelc@cs.wisc.edu>

If the driver knows when hardware is removed like with cxgb3i,
bnx2i, qla4xxx and iser then we will want to remove the sessions/devices
that are bound to that device before removing the host.

cxgb3i and in the future bnx2i will remove the host and that will
remove all the sessions on the hba. iser can call iscsi_kill_session
when it gets an event that indicates that a hca is removed.
And when qla4xxx is hooked in to the lib (it is only hooked into
the class right now) it can call iscsi remove host like the
partial offload card drivers.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
---
 drivers/infiniband/ulp/iser/iscsi_iser.c |    1 +
 drivers/scsi/iscsi_tcp.c                 |    1 +
 drivers/scsi/libiscsi.c                  |  107 +++++++++++++++++++++++++++--
 drivers/scsi/qla4xxx/ql4_os.c            |    2 +-
 drivers/scsi/scsi_transport_iscsi.c      |    6 +-
 include/scsi/iscsi_if.h                  |    1 +
 include/scsi/libiscsi.h                  |   13 ++++
 include/scsi/scsi_transport_iscsi.h      |    3 +-
 8 files changed, 121 insertions(+), 13 deletions(-)

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c
index 5a1cf25..0474da1 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.c
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.c
@@ -378,6 +378,7 @@ static void iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session)
 {
 	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 
+	iscsi_session_teardown(cls_session);
 	iscsi_host_remove(shost);
 	iscsi_host_free(shost);
 }
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index e960f00..752f428 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -1885,6 +1885,7 @@ static void iscsi_tcp_session_destroy(struct iscsi_cls_session *cls_session)
 	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 
 	iscsi_r2tpool_free(cls_session->dd_data);
+	iscsi_session_teardown(cls_session);
 
 	iscsi_host_remove(shost);
 	iscsi_host_free(shost);
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index f9539af..3907818 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -983,6 +983,38 @@ struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
 }
 EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
 
+void iscsi_session_failure(struct iscsi_cls_session *cls_session,
+			   enum iscsi_err err)
+{
+	struct iscsi_session *session = cls_session->dd_data;
+	struct iscsi_conn *conn;
+	struct device *dev;
+	unsigned long flags;
+
+	spin_lock_irqsave(&session->lock, flags);
+	conn = session->leadconn;
+	if (session->state == ISCSI_STATE_TERMINATE || !conn) {
+		spin_unlock_irqrestore(&session->lock, flags);
+		return;
+	}
+
+	dev = get_device(&conn->cls_conn->dev);
+	spin_unlock_irqrestore(&session->lock, flags);
+	if (!dev)
+	        return;
+	/*
+	 * if the host is being removed bypass the connection
+	 * recovery initialization because we are going to kill
+	 * the session.
+	 */
+	if (err == ISCSI_ERR_INVALID_HOST)
+		iscsi_conn_error_event(conn->cls_conn, err);
+	else
+		iscsi_conn_failure(conn, err);
+	put_device(dev);
+}
+EXPORT_SYMBOL_GPL(iscsi_session_failure);
+
 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 {
 	struct iscsi_session *session = conn->session;
@@ -997,9 +1029,10 @@ void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
 	if (conn->stop_stage == 0)
 		session->state = ISCSI_STATE_FAILED;
 	spin_unlock_irqrestore(&session->lock, flags);
+
 	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
-	iscsi_conn_error(conn->cls_conn, err);
+	iscsi_conn_error_event(conn->cls_conn, err);
 }
 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
 
@@ -1905,6 +1938,7 @@ struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
 				   int dd_data_size, uint16_t qdepth)
 {
 	struct Scsi_Host *shost;
+	struct iscsi_host *ihost;
 
 	shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
 	if (!shost)
@@ -1919,22 +1953,43 @@ struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
 		qdepth = ISCSI_DEF_CMD_PER_LUN;
 	}
 	shost->cmd_per_lun = qdepth;
+
+	ihost = shost_priv(shost);
+	spin_lock_init(&ihost->lock);
+	ihost->state = ISCSI_HOST_SETUP;
+	ihost->num_sessions = 0;
+	init_waitqueue_head(&ihost->session_removal_wq);
 	return shost;
 }
 EXPORT_SYMBOL_GPL(iscsi_host_alloc);
 
+static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
+{
+	iscsi_session_failure(cls_session, ISCSI_ERR_INVALID_HOST);
+}
+
 /**
  * iscsi_host_remove - remove host and sessions
  * @shost: scsi host
  *
- * This will also remove any sessions attached to the host, but if userspace
- * is managing the session at the same time this will break. TODO: add
- * refcounting to the netlink iscsi interface so a rmmod or host hot unplug
- * does not remove the memory from under us.
+ * If there are any sessions left, this will initiate the removal and wait
+ * for the completion.
  */
 void iscsi_host_remove(struct Scsi_Host *shost)
 {
-	iscsi_host_for_each_session(shost, iscsi_session_teardown);
+	struct iscsi_host *ihost = shost_priv(shost);
+	unsigned long flags;
+
+	spin_lock_irqsave(&ihost->lock, flags);
+	ihost->state = ISCSI_HOST_REMOVED;
+	spin_unlock_irqrestore(&ihost->lock, flags);
+
+	iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
+	wait_event_interruptible(ihost->session_removal_wq,
+				 ihost->num_sessions == 0);
+	if (signal_pending(current))
+		flush_signals(current);
+
 	scsi_remove_host(shost);
 }
 EXPORT_SYMBOL_GPL(iscsi_host_remove);
@@ -1950,6 +2005,27 @@ void iscsi_host_free(struct Scsi_Host *shost)
 }
 EXPORT_SYMBOL_GPL(iscsi_host_free);
 
+static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
+{
+	struct iscsi_host *ihost = shost_priv(shost);
+	unsigned long flags;
+
+	shost = scsi_host_get(shost);
+	if (!shost) {
+		printk(KERN_ERR "Invalid state. Cannot notify host removal "
+		      "of session teardown event because host already "
+		      "removed.\n");
+		return;
+	}
+
+	spin_lock_irqsave(&ihost->lock, flags);
+	ihost->num_sessions--;
+	if (ihost->num_sessions == 0)
+		wake_up(&ihost->session_removal_wq);
+	spin_unlock_irqrestore(&ihost->lock, flags);
+	scsi_host_put(shost);
+}
+
 /**
  * iscsi_session_setup - create iscsi cls session and host and session
  * @iscsit: iscsi transport template
@@ -1970,9 +2046,19 @@ iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
 		    uint16_t cmds_max, int cmd_task_size,
 		    uint32_t initial_cmdsn, unsigned int id)
 {
+	struct iscsi_host *ihost = shost_priv(shost);
 	struct iscsi_session *session;
 	struct iscsi_cls_session *cls_session;
 	int cmd_i, scsi_cmds, total_cmds = cmds_max;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ihost->lock, flags);
+	if (ihost->state == ISCSI_HOST_REMOVED) {
+		spin_unlock_irqrestore(&ihost->lock, flags);
+		return NULL;
+	}
+	ihost->num_sessions++;
+	spin_unlock_irqrestore(&ihost->lock, flags);
 
 	if (!total_cmds)
 		total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
@@ -1985,7 +2071,7 @@ iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
 		printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
 		       "must be a power of two that is at least %d.\n",
 		       total_cmds, ISCSI_TOTAL_CMDS_MIN);
-		return NULL;
+		goto dec_session_count;
 	}
 
 	if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
@@ -2009,7 +2095,7 @@ iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
 	cls_session = iscsi_alloc_session(shost, iscsit,
 					  sizeof(struct iscsi_session));
 	if (!cls_session)
-		return NULL;
+		goto dec_session_count;
 	session = cls_session->dd_data;
 	session->cls_session = cls_session;
 	session->host = shost;
@@ -2048,6 +2134,7 @@ iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
 
 	if (iscsi_add_session(cls_session, id))
 		goto cls_session_fail;
+
 	return cls_session;
 
 cls_session_fail:
@@ -2056,6 +2143,8 @@ module_get_fail:
 	iscsi_pool_free(&session->cmdpool);
 cmdpool_alloc_fail:
 	iscsi_free_session(cls_session);
+dec_session_count:
+	iscsi_host_dec_session_cnt(shost);
 	return NULL;
 }
 EXPORT_SYMBOL_GPL(iscsi_session_setup);
@@ -2071,6 +2160,7 @@ void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
 {
 	struct iscsi_session *session = cls_session->dd_data;
 	struct module *owner = cls_session->transport->owner;
+	struct Scsi_Host *shost = session->host;
 
 	iscsi_pool_free(&session->cmdpool);
 
@@ -2083,6 +2173,7 @@ void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
 	kfree(session->ifacename);
 
 	iscsi_destroy_session(cls_session);
+	iscsi_host_dec_session_cnt(shost);
 	module_put(owner);
 }
 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index 4255b36..db7ea3b 100644
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -353,7 +353,7 @@ void qla4xxx_mark_device_missing(struct scsi_qla_host *ha,
 		      ha->host_no, ddb_entry->bus, ddb_entry->target,
 		      ddb_entry->fw_ddb_index));
 	iscsi_block_session(ddb_entry->sess);
-	iscsi_conn_error(ddb_entry->conn, ISCSI_ERR_CONN_FAILED);
+	iscsi_conn_error_event(ddb_entry->conn, ISCSI_ERR_CONN_FAILED);
 }
 
 static struct srb* qla4xxx_get_new_srb(struct scsi_qla_host *ha,
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index cbaae48..f9e45f8 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -1010,7 +1010,7 @@ int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 
 	skb = alloc_skb(len, GFP_ATOMIC);
 	if (!skb) {
-		iscsi_conn_error(conn, ISCSI_ERR_CONN_FAILED);
+		iscsi_conn_error_event(conn, ISCSI_ERR_CONN_FAILED);
 		iscsi_cls_conn_printk(KERN_ERR, conn, "can not deliver "
 				      "control PDU: OOM\n");
 		return -ENOMEM;
@@ -1031,7 +1031,7 @@ int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 }
 EXPORT_SYMBOL_GPL(iscsi_recv_pdu);
 
-void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error)
+void iscsi_conn_error_event(struct iscsi_cls_conn *conn, enum iscsi_err error)
 {
 	struct nlmsghdr	*nlh;
 	struct sk_buff	*skb;
@@ -1063,7 +1063,7 @@ void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error)
 	iscsi_cls_conn_printk(KERN_INFO, conn, "detected conn error (%d)\n",
 			      error);
 }
-EXPORT_SYMBOL_GPL(iscsi_conn_error);
+EXPORT_SYMBOL_GPL(iscsi_conn_error_event);
 
 static int
 iscsi_if_send_reply(int pid, int seq, int type, int done, int multi,
diff --git a/include/scsi/iscsi_if.h b/include/scsi/iscsi_if.h
index 16be12f..f274d24 100644
--- a/include/scsi/iscsi_if.h
+++ b/include/scsi/iscsi_if.h
@@ -213,6 +213,7 @@ enum iscsi_err {
 	ISCSI_ERR_DATA_DGST		= ISCSI_ERR_BASE + 15,
 	ISCSI_ERR_PARAM_NOT_FOUND	= ISCSI_ERR_BASE + 16,
 	ISCSI_ERR_NO_SCSI_CMD		= ISCSI_ERR_BASE + 17,
+	ISCSI_ERR_INVALID_HOST		= ISCSI_ERR_BASE + 18,
 };
 
 /*
diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
index 5e75bb7..7d8cd15 100644
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -287,6 +287,11 @@ struct iscsi_session {
 	struct iscsi_pool	cmdpool;	/* PDU's pool */
 };
 
+enum {
+	ISCSI_HOST_SETUP,
+	ISCSI_HOST_REMOVED,
+};
+
 struct iscsi_host {
 	char			*initiatorname;
 	/* hw address or netdev iscsi connection is bound to */
@@ -295,6 +300,12 @@ struct iscsi_host {
 	/* local address */
 	int			local_port;
 	char			local_address[ISCSI_ADDRESS_BUF_LEN];
+
+	wait_queue_head_t	session_removal_wq;
+	/* protects sessions and state */
+	spinlock_t		lock;
+	int			num_sessions;
+	int			state;
 };
 
 /*
@@ -351,6 +362,8 @@ extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
 			   int);
 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
+extern void iscsi_session_failure(struct iscsi_cls_session *cls_session,
+				  enum iscsi_err err);
 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
 				enum iscsi_param param, char *buf);
 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index 8b6c91d..8749d4d 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -135,7 +135,8 @@ extern int iscsi_unregister_transport(struct iscsi_transport *tt);
 /*
  * control plane upcalls
  */
-extern void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error);
+extern void iscsi_conn_error_event(struct iscsi_cls_conn *conn,
+				   enum iscsi_err error);
 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
 			  char *data, uint32_t data_size);
 
-- 
1.5.4.1

[PATCH 3/7] iscsi class: fix endpoint id handling

[michaelc]

From: Mike Christie <michaelc@cs.wisc.edu>

Some endpoint code was using unsigned int and some
was using uint64_t. This converts it all to uint64_t.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
---
 drivers/scsi/scsi_transport_iscsi.c |    9 +++++----
 include/scsi/scsi_transport_iscsi.h |    2 +-
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index f9e45f8..4a803eb 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -138,7 +138,7 @@ static ssize_t
 show_ep_handle(struct device *dev, struct device_attribute *attr, char *buf)
 {
 	struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
-	return sprintf(buf, "%u\n", ep->id);
+	return sprintf(buf, "%llu\n", (unsigned long long) ep->id);
 }
 static ISCSI_ATTR(ep, handle, S_IRUGO, show_ep_handle, NULL);
 
@@ -156,7 +156,7 @@ static struct attribute_group iscsi_endpoint_group = {
 static int iscsi_match_epid(struct device *dev, void *data)
 {
 	struct iscsi_endpoint *ep = iscsi_dev_to_endpoint(dev);
-	unsigned int *epid = (unsigned int *) data;
+	uint64_t *epid = (uint64_t *) data;
 
 	return *epid == ep->id;
 }
@@ -166,7 +166,7 @@ iscsi_create_endpoint(int dd_size)
 {
 	struct device *dev;
 	struct iscsi_endpoint *ep;
-	unsigned int id;
+	uint64_t id;
 	int err;
 
 	for (id = 1; id < ISCSI_MAX_EPID; id++) {
@@ -187,7 +187,8 @@ iscsi_create_endpoint(int dd_size)
 
 	ep->id = id;
 	ep->dev.class = &iscsi_endpoint_class;
-	snprintf(ep->dev.bus_id, BUS_ID_SIZE, "ep-%u", id);
+	snprintf(ep->dev.bus_id, BUS_ID_SIZE, "ep-%llu",
+		 (unsigned long long) id);
 	err = device_register(&ep->dev);
         if (err)
                 goto free_ep;
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index 8749d4d..c667cc3 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -208,7 +208,7 @@ extern void iscsi_host_for_each_session(struct Scsi_Host *shost,
 struct iscsi_endpoint {
 	void *dd_data;			/* LLD private data */
 	struct device dev;
-	unsigned int id;
+	uint64_t id;
 };
 
 /*
-- 
1.5.4.1

[PATCH 4/7] libiscsi: rename host reset to target reset

[michaelc]

From: Mike Christie <michaelc@cs.wisc.edu>

I had this in my patchset to add target reset support, but
it got dropped due to patching conflicts. This initial patch
just renames the function and users. We are actually just
dropping the session, and so this does not have anything to do
with the host exactly. It does for software iscsi because
we allocate a host per session, but for cxgb3i this makes no
sense.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
---
 drivers/infiniband/ulp/iser/iscsi_iser.c |    2 +-
 drivers/scsi/iscsi_tcp.c                 |    2 +-
 drivers/scsi/libiscsi.c                  |   10 +++++-----
 include/scsi/libiscsi.h                  |    2 +-
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c
index 0474da1..1e5b644 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.c
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.c
@@ -598,7 +598,7 @@ static struct scsi_host_template iscsi_iser_sht = {
 	.cmd_per_lun            = ISCSI_MAX_CMD_PER_LUN,
 	.eh_abort_handler       = iscsi_eh_abort,
 	.eh_device_reset_handler= iscsi_eh_device_reset,
-	.eh_host_reset_handler	= iscsi_eh_host_reset,
+	.eh_target_reset_handler= iscsi_eh_target_reset,
 	.use_clustering         = DISABLE_CLUSTERING,
 	.proc_name              = "iscsi_iser",
 	.this_id                = -1,
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 752f428..4f096de 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -1909,7 +1909,7 @@ static struct scsi_host_template iscsi_sht = {
 	.cmd_per_lun		= ISCSI_DEF_CMD_PER_LUN,
 	.eh_abort_handler       = iscsi_eh_abort,
 	.eh_device_reset_handler= iscsi_eh_device_reset,
-	.eh_host_reset_handler	= iscsi_eh_host_reset,
+	.eh_target_reset_handler= iscsi_eh_target_reset,
 	.use_clustering         = DISABLE_CLUSTERING,
 	.slave_configure        = iscsi_tcp_slave_configure,
 	.proc_name		= "iscsi_tcp",
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 3907818..e3e57cc 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -1367,7 +1367,7 @@ void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
 }
 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
 
-int iscsi_eh_host_reset(struct scsi_cmnd *sc)
+int iscsi_eh_target_reset(struct scsi_cmnd *sc)
 {
 	struct iscsi_cls_session *cls_session;
 	struct iscsi_session *session;
@@ -1381,7 +1381,7 @@ int iscsi_eh_host_reset(struct scsi_cmnd *sc)
 	spin_lock_bh(&session->lock);
 	if (session->state == ISCSI_STATE_TERMINATE) {
 failed:
-		debug_scsi("failing host reset: session terminated "
+		debug_scsi("failing target reset: session terminated "
 			   "[CID %d age %d]\n", conn->id, session->age);
 		spin_unlock_bh(&session->lock);
 		mutex_unlock(&session->eh_mutex);
@@ -1396,7 +1396,7 @@ failed:
 	 */
 	iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 
-	debug_scsi("iscsi_eh_host_reset wait for relogin\n");
+	debug_scsi("iscsi_eh_target_reset wait for relogin\n");
 	wait_event_interruptible(conn->ehwait,
 				 session->state == ISCSI_STATE_TERMINATE ||
 				 session->state == ISCSI_STATE_LOGGED_IN ||
@@ -1408,14 +1408,14 @@ failed:
 	spin_lock_bh(&session->lock);
 	if (session->state == ISCSI_STATE_LOGGED_IN)
 		iscsi_session_printk(KERN_INFO, session,
-				     "host reset succeeded\n");
+				     "target reset succeeded\n");
 	else
 		goto failed;
 	spin_unlock_bh(&session->lock);
 	mutex_unlock(&session->eh_mutex);
 	return SUCCESS;
 }
-EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
+EXPORT_SYMBOL_GPL(iscsi_eh_target_reset);
 
 static void iscsi_tmf_timedout(unsigned long data)
 {
diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
index 7d8cd15..61e53f1 100644
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -313,7 +313,7 @@ struct iscsi_host {
  */
 extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
-extern int iscsi_eh_host_reset(struct scsi_cmnd *sc);
+extern int iscsi_eh_target_reset(struct scsi_cmnd *sc);
 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
 extern int iscsi_queuecommand(struct scsi_cmnd *sc,
 			      void (*done)(struct scsi_cmnd *));
-- 
1.5.4.1

[PATCH 5/7] iscsi_tcp: return a descriptive error value during connection errors

[michaelc]

From: Mike Christie <michaelc@cs.wisc.edu>

The segment->done functions return a iscsi error value which gives
a lot more info than conn failed, so this patch has us return
that value. I also add a new one for xmit failures.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
---
 drivers/scsi/iscsi_tcp.c |   12 +++++++-----
 include/scsi/iscsi_if.h  |    1 +
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 4f096de..ed6c54c 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -979,7 +979,7 @@ iscsi_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
 
 error:
 	debug_tcp("Error receiving PDU, errno=%d\n", rc);
-	iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
+	iscsi_conn_failure(conn, rc);
 	return 0;
 }
 
@@ -1098,8 +1098,10 @@ iscsi_xmit(struct iscsi_conn *conn)
 
 	while (1) {
 		rc = iscsi_tcp_xmit_segment(tcp_conn, segment);
-		if (rc < 0)
+		if (rc < 0) {
+			rc = ISCSI_ERR_XMIT_FAILED;
 			goto error;
+		}
 		if (rc == 0)
 			break;
 
@@ -1108,7 +1110,7 @@ iscsi_xmit(struct iscsi_conn *conn)
 		if (segment->total_copied >= segment->total_size) {
 			if (segment->done != NULL) {
 				rc = segment->done(tcp_conn, segment);
-				if (rc < 0)
+				if (rc != 0)
 					goto error;
 			}
 		}
@@ -1123,8 +1125,8 @@ error:
 	/* Transmit error. We could initiate error recovery
 	 * here. */
 	debug_tcp("Error sending PDU, errno=%d\n", rc);
-	iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
-	return rc;
+	iscsi_conn_failure(conn, rc);
+	return -EIO;
 }
 
 /**
diff --git a/include/scsi/iscsi_if.h b/include/scsi/iscsi_if.h
index f274d24..0c9514d 100644
--- a/include/scsi/iscsi_if.h
+++ b/include/scsi/iscsi_if.h
@@ -214,6 +214,7 @@ enum iscsi_err {
 	ISCSI_ERR_PARAM_NOT_FOUND	= ISCSI_ERR_BASE + 16,
 	ISCSI_ERR_NO_SCSI_CMD		= ISCSI_ERR_BASE + 17,
 	ISCSI_ERR_INVALID_HOST		= ISCSI_ERR_BASE + 18,
+	ISCSI_ERR_XMIT_FAILED		= ISCSI_ERR_BASE + 19,
 };
 
 /*
-- 
1.5.4.1

[PATCH 6/7] libiscsi: check reason why we are stopping iscsi session to determine error value

[michaelc]

From: Mike Christie <michaelc@cs.wisc.edu>

Some wires got crossed on some patches and I messed up in the code
below when rebuilding a patch. We want to be checking if flag
equaled the value indicating if we killing the session due to
final logout or if we just trying to relogin.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
---
 drivers/scsi/libiscsi.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index e3e57cc..5aa0db1 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -2453,7 +2453,7 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
 	 * flush queues.
 	 */
 	spin_lock_bh(&session->lock);
-	if (STOP_CONN_RECOVER)
+	if (flag == STOP_CONN_RECOVER)
 		fail_all_commands(conn, -1, DID_TRANSPORT_DISRUPTED);
 	else
 		fail_all_commands(conn, -1, DID_ERROR);
-- 
1.5.4.1

[PATCH 7/7] libiscsi: fix locking in iscsi_eh_device_reset

[michaelc]

From: Mike Christie <michaelc@cs.wisc.edu>

We must be using the bh spin locking functions in
iscsi_eh_device_reset becuase the session lock interacts with
a thread and softirq.

This patch also fixes up a bogus comment and check in fail_command,
because no one drops the lock (bnx2i did but it is not going
upstream yet and there were other refcount changes for that).

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
---
 drivers/scsi/libiscsi.c |    9 ++-------
 1 files changed, 2 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 5aa0db1..801c7cf 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -404,11 +404,6 @@ static void fail_command(struct iscsi_conn *conn, struct iscsi_task *task,
 		conn->session->queued_cmdsn--;
 	else
 		conn->session->tt->cleanup_task(conn, task);
-	/*
-	 * Check if cleanup_task dropped the lock and the command completed,
-	 */
-	if (!task->sc)
-		return;
 
 	sc->result = err;
 	if (!scsi_bidi_cmnd(sc))
@@ -1829,10 +1824,10 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc)
 
 	iscsi_suspend_tx(conn);
 
-	spin_lock(&session->lock);
+	spin_lock_bh(&session->lock);
 	fail_all_commands(conn, sc->device->lun, DID_ERROR);
 	conn->tmf_state = TMF_INITIAL;
-	spin_unlock(&session->lock);
+	spin_unlock_bh(&session->lock);
 
 	iscsi_start_tx(conn);
 	goto done;
-- 
1.5.4.1

Re: iscsi update for scsi-post

[Mike Christie]

michaelc@cs.wisc.edu wrote:
> The following patches are fixes and enhancements for 2.6.28 scsi-post,

I meant the 2.6.28 feature window. The patches are made over scsi-post 
instead of scsi-misc because of the new DID_TRANSPORT error patches,

Sorry about the bad wording.

> becuase:
> 
> Subject: [PATCH 6/7] libiscsi: check reason why we are stopping iscsi session to determine error value
> 
> collides with other patches in that tree.
> 
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html