path: root/include/scsi
diff options
authorChristof Schmitt <christof.schmitt@de.ibm.com>2010-03-24 16:50:30 +0100
committerJames Bottomley <James.Bottomley@suse.de>2010-04-11 09:49:33 -0500
commit2f2eb58762b4dcddfe25c90800323765c1257eca (patch)
treef69788ac1afc0b7924a033cb82f33dbc55b6af1c /include/scsi
parent[SCSI] qla2xxx: Fix documentation of ql2xfdmienable module parameter (diff)
[SCSI] Allow FC LLD to fast-fail scsi eh by introducing new eh return
If the scsi eh is running and then a FC LLD calls fc_remote_port_delete, the SCSI commands sent from the eh will fail. To prevent this, a FC LLD can call fc_block_scsi_eh from the eh callback, blocking the eh thread until the dev_loss_tmo fires or the remote port is available again. If (e.g. for a multipathing setup) the dev_loss_tmo is set to a very large value, thus preventing the scsi device removal , the scsi eh can block for a long time. For multipathing, the fast_io_fail_tmo is then set to a low value to detect path problems sooner. This patch introduces a new return code FAST_IO_FAIL. The function fc_block_scsi_eh now returns FAST_IO_FAIL when the fast_io_fail_tmo fires. This indicates that the LLD terminated all pending I/O requests and there are no more pending SCSI commands for the scsi eh to wait for. This return code can be passed back to the scsi eh to stop the escalation and finish the recovery process for this device. Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Diffstat (limited to 'include/scsi')
2 files changed, 2 insertions, 1 deletions
diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h
index 8b4deca996ad..832f41f37385 100644
--- a/include/scsi/scsi.h
+++ b/include/scsi/scsi.h
@@ -423,6 +423,7 @@ static inline int scsi_is_wlun(unsigned int lun)
#define ADD_TO_MLQUEUE 0x2006
#define TIMEOUT_ERROR 0x2007
+#define FAST_IO_FAIL 0x2009
* Midlevel queue return values.
diff --git a/include/scsi/scsi_transport_fc.h b/include/scsi/scsi_transport_fc.h
index 8e86a94faf06..87d81b3ce564 100644
--- a/include/scsi/scsi_transport_fc.h
+++ b/include/scsi/scsi_transport_fc.h
@@ -807,6 +807,6 @@ void fc_host_post_vendor_event(struct Scsi_Host *shost, u32 event_number,
struct fc_vport *fc_vport_create(struct Scsi_Host *shost, int channel,
struct fc_vport_identifiers *);
int fc_vport_terminate(struct fc_vport *vport);
-void fc_block_scsi_eh(struct scsi_cmnd *cmnd);
+int fc_block_scsi_eh(struct scsi_cmnd *cmnd);
#endif /* SCSI_TRANSPORT_FC_H */