hunk by hunk:
- CHECK_CONDITION is what happens to cmnd->status >> 1
or after status_byte() macro. But here it is used
directly on status which means 0x1 which is an undefined
bit in the standard. And is a status that will never
return from a target.
- in busfree_run at the DONE_SC phase we have 3 distinct
operation:
1-if(DONE_SC->SCp.phase & check_condition)
The REQUEST_SENSE command return.
- Restore original command
- Than continue to operation 3.
2-if(DONE_SC->SCp.Status==SAM_STAT_CHECK_CONDITION)
A regular command returned with a status.
- Internally re-Q a REQUEST_SENSE.
- Do not do operation 3.
3-
- Complete the command and return it to scsi-ml
So the 0x2 in both these operations (1,2) means the scsi
check-condition status, hence SAM_STAT_CHECK_CONDITION
- Here the code asks about !(DONE_SC->SCp.Status & not_issued)
but "not_issued" is an enum belonging to the "phase" member
and not to the Status returned from target. The reason this
works is because not_issued==1 and Also CHECK_CONDITION==1
(remember from hunk 1). So actually the code was asking
!(DONE_SC->SCp.Status & CHECK_CONDITION). Which means
"Has the status been read from target yet?"
Staus is read at status_run(). "not_issued" is
cleared in seldo_run() which is usually earlier than
status_run().
So this patch does nothing as far as assembly is concerned
but it does let the reader understand what is going on.
---
drivers/scsi/aha152x.c | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/scsi/aha152x.c b/drivers/scsi/aha152x.c
index 85f2394..29253f9 100644
--- a/drivers/scsi/aha152x.c
+++ b/drivers/scsi/aha152x.c
@@ -986,7 +986,7 @@ static int aha152x_internal_queue(Scsi_Cmnd *SCpnt, struct completion *complete,
SCpnt->scsi_done = done;
SCpnt->resid = SCpnt->request_bufflen;
SCpnt->SCp.phase = not_issued | phase;
- SCpnt->SCp.Status = CHECK_CONDITION;
+ SCpnt->SCp.Status = 0x1; /* Ilegal status by SCSI standard */
SCpnt->SCp.Message = 0;
SCpnt->SCp.have_data_in = 0;
SCpnt->SCp.sent_command = 0;
@@ -1574,12 +1574,12 @@ static void busfree_run(struct Scsi_Host *shpnt)
cmd->use_sg = sc->use_sg;
cmd->cmd_len = sc->cmd_len;
- cmd->SCp.Status = 0x02;
+ cmd->SCp.Status = SAM_STAT_CHECK_CONDITION;
HOSTDATA(shpnt)->commands--;
if (!HOSTDATA(shpnt)->commands)
SETPORT(PORTA, 0); /* turn led off */
- } else if(DONE_SC->SCp.Status==0x02) {
+ } else if(DONE_SC->SCp.Status==SAM_STAT_CHECK_CONDITION) {
#if defined(AHA152X_STAT)
HOSTDATA(shpnt)->busfree_with_check_condition++;
#endif
@@ -1587,7 +1587,7 @@ static void busfree_run(struct Scsi_Host *shpnt)
DPRINTK(debug_eh, ERR_LEAD "CHECK CONDITION found\n", CMDINFO(DONE_SC));
#endif
- if(!(DONE_SC->SCp.Status & not_issued)) {
+ if(!(DONE_SC->SCp.phase & not_issued)) {
Scsi_Cmnd *ptr = DONE_SC;
DONE_SC=NULL;
#if 0
--
1.5.2.2.249.g45fd
-
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