+184
−12
Loading
[SCSI] pm8001: deficient responses to IO_XFER_ERROR_BREAK and IO_XFER_OPEN_RETRY_TIMEOUT
IO_XFER_ERROR_BREAK and IO_XFER_OPEN_RETRY_TIMEOUT are deficient of the required actions as outlined in the programming manual for the pm8001. Due to the overlapping code requirements of these recovery responses, we found it necessary to bundle them together into one patch. When a break is received during the command phase (ssp_completion), this is a result of a timeout or interruption on the bus. Logic suggests that we should retry the command. When a break is received during the data-phase (ssp_event), the task must be aborted on the target or it will retain a data-phase lock turning the target reticent to all future media commands yet will successfully respond to TUR, INQUIRY and ABORT leading eventually to target failure through several abort-cycle loops. The open retry interval is exceedingly short resulting in occasional target drop-off during expander resets or when targets push-back during bad-block remapping. Increased effective timeout from 130ms to 1.5 seconds for each try so as to trigger after the administrative inquiry/tur timeout in the scsi subsystem to keep error-recovery harmonics to a minimum. When an open retry timeout event is received, the action required by the targets is to issue an abort for the outstanding command then logic suggests we retry the command as this state is usually an indication of a credit block or busy condition on the target. We hijacked the pm8001_handle_event work queue handler so that it will handle task as an argument instead of device for the workers in support of the deferred handling outlined above. Moderate to Heavy bad-path testing on a 2.6.32 vintage kernel, compile-testing on scsi-misc-2.6 kernel ... Signed-off-by:Mark Salyzyn <mark_salyzyn@xyratex.com> Acked-by: