[SCSI] sym53c8xx: Keep transfer negotiations valid

(The patch updated based on testing and comments from Tony Battersby.)

Change the sym53c8xx_2 driver negotiation logic so that the driver will
tolerate better device removals. Negotiation message(s) will be sent
with every INQUIRY and REQUEST SENSE command, and whenever there is a
change in goals or when the device reports check condition.

The patch was made specifically to address the case where you hotswap
the disk using remove-single-device/add-single-device commands through
/proc/scsi/scsi. Without the patch the driver keeps using old transfer
parameters even though the target is reset and reports check condition,
so the data transfer of the very first INQUIRY will fail.

Signed-off-by: Aaro Koskinen <Aaro.Koskinen@nokia.com>
Tested-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/scsi/sym53c8xx_2/sym_hipd.h b/drivers/scsi/sym53c8xx_2/sym_hipd.h
index ad078805e62..233a3d0b2ce 100644
--- a/drivers/scsi/sym53c8xx_2/sym_hipd.h
+++ b/drivers/scsi/sym53c8xx_2/sym_hipd.h
@@ -354,6 +354,7 @@ struct sym_trans {
         unsigned int dt:1;
         unsigned int qas:1;
         unsigned int check_nego:1;
+        unsigned int renego:2;
 };
 
 /*