On Tue, Mar 24, 2009 at 10:46:09AM -0700, Mike Anderson wrote: > Brian King <brking@xxxxxxxxxxxxxxxxxx> wrote: > > Your assessment sounds correct to me. The other caveat to note is that > > if for some reason in your eh_abort_handler you don't think the command > > is still outstanding, you should return SUCCESS for this as well. > > > > -Brian > > > > Christof Schmitt wrote: > > > I am investigating what is required from a LLD when SCSI commands time > > > out and the SCSI EH calls the eh_abort_handler. The documentation in > > > scsi_eh.txt states: > > > > > > <<scsi_eh_abort_cmds>> > > > > > > This action is taken for each timed out command. > > > hostt->eh_abort_handler() is invoked for each scmd. The > > > handler returns SUCCESS if it has succeeded to make LLDD and > > > all related hardware forget about the scmd. > > > > > > From this and from looking at the code, i would conclude: > > > > > > 1) If the LLD returns FAILED from the eh_abort_handler, then the > > > command is still allowed to be active in the LLD and the LLD can > > > call scsi_done any time later (probably latest when the > > > eh_host_reset_handler flushes everything that is still pending). > > > > > > 2) While the abort is pending, but before returning SUCCESS from > > > eh_abort_handler, the LLD can still call scsi_done for the SCSI > > > command to be aborted (the SCSI command might be returned with a > > > status "aborted" if the abort succeeds, or "good" if it was > > > completed just before the abort reached the storage system). > > > > > In cases 1 and 2 above calling scsi_done can be done but will cause > the request to be stopped in blk_complete_request > (scsi_done->blk_complete_request) as the timed out handler has > already taken ownership of the command. I am not too familiar with the blk completion handling. Would calling scsi_done for the cases above cause any problems? If there are reasons not to call scsi_done here, then this could be mentioned in the scsi documentation file. -- Christof Schmitt -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
