[SCSI] libsas: Don't give scsi_cmnds to the EH if they never made it to the SAS LLDD or have already returned

On a system with many SAS targets, it appears possible that a scsi_cmnd
can time out without ever making it to the SAS LLDD or at the same time
that a completion is occurring.  In both of these cases, telling the
LLDD to abort the sas_task makes no sense because the LLDD won't know
about the sas_task; what we really want to do is to increase the timer.
Note that this involves creating another sas_task bit to indicate
whether or not the task has been sent to the LLDD; I could have
implemented this by slightly redefining SAS_TASK_STATE_PENDING, but
this way seems cleaner.

This second version amends the aic94xx portion to set the
TASK_AT_INITIATOR flag for all sas_tasks that were passed to
lldd_execute_task.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This commit is contained in:
Darrick J. Wong 2007-01-11 14:14:55 -08:00 committed by James Bottomley
parent bf45120751
commit b218a0d8e2
3 changed files with 17 additions and 0 deletions

View File

@ -349,6 +349,7 @@ Again:
spin_lock_irqsave(&task->task_state_lock, flags);
task->task_state_flags &= ~SAS_TASK_STATE_PENDING;
task->task_state_flags &= ~SAS_TASK_AT_INITIATOR;
task->task_state_flags |= SAS_TASK_STATE_DONE;
if (unlikely((task->task_state_flags & SAS_TASK_STATE_ABORTED))) {
spin_unlock_irqrestore(&task->task_state_lock, flags);
@ -557,6 +558,7 @@ int asd_execute_task(struct sas_task *task, const int num,
struct sas_task *t = task;
struct asd_ascb *ascb = NULL, *a;
struct asd_ha_struct *asd_ha = task->dev->port->ha->lldd_ha;
unsigned long flags;
res = asd_can_queue(asd_ha, num);
if (res)
@ -599,6 +601,10 @@ int asd_execute_task(struct sas_task *task, const int num,
}
if (res)
goto out_err_unmap;
spin_lock_irqsave(&t->task_state_lock, flags);
t->task_state_flags |= SAS_TASK_AT_INITIATOR;
spin_unlock_irqrestore(&t->task_state_lock, flags);
}
list_del_init(&alist);
@ -617,6 +623,9 @@ out_err_unmap:
if (a == b)
break;
t = a->uldd_task;
spin_lock_irqsave(&t->task_state_lock, flags);
t->task_state_flags &= ~SAS_TASK_AT_INITIATOR;
spin_unlock_irqrestore(&t->task_state_lock, flags);
switch (t->task_proto) {
case SATA_PROTO:
case SAS_PROTO_STP:

View File

@ -542,6 +542,13 @@ enum scsi_eh_timer_return sas_scsi_timed_out(struct scsi_cmnd *cmd)
cmd, task);
return EH_HANDLED;
}
if (!(task->task_state_flags & SAS_TASK_AT_INITIATOR)) {
spin_unlock_irqrestore(&task->task_state_lock, flags);
SAS_DPRINTK("command 0x%p, task 0x%p, not at initiator: "
"EH_RESET_TIMER\n",
cmd, task);
return EH_RESET_TIMER;
}
task->task_state_flags |= SAS_TASK_STATE_ABORTED;
spin_unlock_irqrestore(&task->task_state_lock, flags);

View File

@ -554,6 +554,7 @@ struct sas_task {
#define SAS_TASK_STATE_DONE 2
#define SAS_TASK_STATE_ABORTED 4
#define SAS_TASK_INITIATOR_ABORTED 8
#define SAS_TASK_AT_INITIATOR 16
static inline struct sas_task *sas_alloc_task(gfp_t flags)
{