[PATCH] FC transport: Allow LLDD to disable LUN scanning

[PATCH] FC transport: Allow LLDD to disable LUN scanning

[Christof Schmitt]

From: Christof Schmitt <christof.schmitt@de.ibm.com>

Introduce a flag that allows the SCSI low level device driver to
disable the automatic scanning for LUNs from the FC transport class.

This is for the zfcp device driver that manages the attached units on
its own and does not want to have the automatic discovery of other
LUNs.

Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
---
 drivers/scsi/scsi_transport_fc.c |    4 +++-
 include/scsi/scsi_transport_fc.h |    3 +++
 2 files changed, 6 insertions(+), 1 deletion(-)

--- linux-2.6.orig/drivers/scsi/scsi_transport_fc.c
+++ linux-2.6/drivers/scsi/scsi_transport_fc.c
@@ -2988,10 +2988,12 @@ fc_scsi_scan_rport(struct work_struct *w
 	struct fc_rport *rport =
 		container_of(work, struct fc_rport, scan_work);
 	struct Scsi_Host *shost = rport_to_shost(rport);
+	struct fc_internal *i = to_fc_internal(shost->transportt);
 	unsigned long flags;
 
 	if ((rport->port_state == FC_PORTSTATE_ONLINE) &&
-	    (rport->roles & FC_PORT_ROLE_FCP_TARGET)) {
+	    (rport->roles & FC_PORT_ROLE_FCP_TARGET) &&
+	    !(i->f->disable_target_scan)) {
 		scsi_scan_target(&rport->dev, rport->channel,
 			rport->scsi_target_id, SCAN_WILD_CARD, 1);
 	}
--- linux-2.6.orig/include/scsi/scsi_transport_fc.h
+++ linux-2.6/include/scsi/scsi_transport_fc.h
@@ -632,6 +632,9 @@ struct fc_function_template {
 	unsigned long	show_host_fabric_name:1;
 	unsigned long	show_host_symbolic_name:1;
 	unsigned long	show_host_system_hostname:1;
+
+	/* The driver can disable the LUN scanning from the FC transport class */
+	unsigned long	disable_target_scan:1;
 };
 
 

Re: [PATCH] FC transport: Allow LLDD to disable LUN scanning

[Matthew Wilcox]

On Tue, Aug 21, 2007 at 05:37:17PM +0200, Christof Schmitt wrote:
>  	unsigned long	show_host_system_hostname:1;
> +
> +	/* The driver can disable the LUN scanning from the FC transport class */
> +	unsigned long	disable_target_scan:1;
>  };

The comment exceeds 80 columns.  Why have a comment at all, none of the
other fields here do, and it doesn't seem to add anything to me.

-- 
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours.  We can't possibly take such
a retrograde step."

Re: [PATCH] FC transport: Allow LLDD to disable LUN scanning

[Christof Schmitt]

On Tue, Aug 21, 2007 at 09:46:34AM -0600, Matthew Wilcox wrote:
> The comment exceeds 80 columns.  Why have a comment at all, none of the
> other fields here do, and it doesn't seem to add anything to me.

Agree. I will remove the comment.

Update: [PATCH] FC transport: Allow LLDD to disable LUN scanning

[Christof Schmitt]

From: Christof Schmitt <christof.schmitt@de.ibm.com>

Introduce a flag that allows the SCSI low level device driver to
disable the automatic scanning for LUNs from the FC transport class.

This is for the zfcp device driver that manages the attached units on
its own and does not want to have the automatic discovery of other
LUNs.

Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
---
 drivers/scsi/scsi_transport_fc.c |    4 +++-
 include/scsi/scsi_transport_fc.h |    2 ++
 2 files changed, 5 insertions(+), 1 deletion(-)

--- linux-2.6.orig/drivers/scsi/scsi_transport_fc.c
+++ linux-2.6/drivers/scsi/scsi_transport_fc.c
@@ -2988,10 +2988,12 @@ fc_scsi_scan_rport(struct work_struct *w
 	struct fc_rport *rport =
 		container_of(work, struct fc_rport, scan_work);
 	struct Scsi_Host *shost = rport_to_shost(rport);
+	struct fc_internal *i = to_fc_internal(shost->transportt);
 	unsigned long flags;
 
 	if ((rport->port_state == FC_PORTSTATE_ONLINE) &&
-	    (rport->roles & FC_PORT_ROLE_FCP_TARGET)) {
+	    (rport->roles & FC_PORT_ROLE_FCP_TARGET) &&
+	    !(i->f->disable_target_scan)) {
 		scsi_scan_target(&rport->dev, rport->channel,
 			rport->scsi_target_id, SCAN_WILD_CARD, 1);
 	}
--- linux-2.6.orig/include/scsi/scsi_transport_fc.h
+++ linux-2.6/include/scsi/scsi_transport_fc.h
@@ -632,6 +632,8 @@ struct fc_function_template {
 	unsigned long	show_host_fabric_name:1;
 	unsigned long	show_host_symbolic_name:1;
 	unsigned long	show_host_system_hostname:1;
+
+	unsigned long	disable_target_scan:1;
 };