[PATCH] qla2xxx: Close window on race between rport removal and fcport transition.

Fcport visibility is recognized during interrupt time, but,
rport removal can only occur during a process
(sleeping)-context.  Return a DID_IMM_RETRY status for
commands submitted within this window to insure I/Os do not
prematurely run-out of retries.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 495ccbc7f8cb..9b5a10ac3e25 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -366,6 +366,12 @@ qla2x00_queuecommand(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
                 goto qc_fail_command;
         }
 
+        /* Close window on fcport/rport state-transitioning. */
+        if (!*(fc_port_t **)rport->dd_data) {
+                cmd->result = DID_IMM_RETRY << 16;
+                goto qc_fail_command;
+        }
+
         if (atomic_read(&fcport->state) != FCS_ONLINE) {
                 if (atomic_read(&fcport->state) == FCS_DEVICE_DEAD ||
                     atomic_read(&ha->loop_state) == LOOP_DEAD) {
@@ -421,6 +427,12 @@ qla24xx_queuecommand(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
                 goto qc24_fail_command;
         }
 
+        /* Close window on fcport/rport state-transitioning. */
+        if (!*(fc_port_t **)rport->dd_data) {
+                cmd->result = DID_IMM_RETRY << 16;
+                goto qc24_fail_command;
+        }
+
         if (atomic_read(&fcport->state) != FCS_ONLINE) {
                 if (atomic_read(&fcport->state) == FCS_DEVICE_DEAD ||
                     atomic_read(&ha->loop_state) == LOOP_DEAD) {
@@ -1675,11 +1687,13 @@ qla2x00_schedule_rport_del(struct scsi_qla_host *ha, fc_port_t *fcport,
                 spin_lock_irqsave(&fcport->rport_lock, flags);
                 fcport->drport = rport;
                 fcport->rport = NULL;
+                *(fc_port_t **)rport->dd_data = NULL;
                 spin_unlock_irqrestore(&fcport->rport_lock, flags);
                 set_bit(FCPORT_UPDATE_NEEDED, &ha->dpc_flags);
         } else {
                 spin_lock_irqsave(&fcport->rport_lock, flags);
                 fcport->rport = NULL;
+                *(fc_port_t **)rport->dd_data = NULL;
                 spin_unlock_irqrestore(&fcport->rport_lock, flags);
                 fc_remote_port_delete(rport);
         }