On Thu, 2015-01-22 at 11:14 +0100, Bart Van Assche wrote: > On 01/22/15 11:02, Nicholas A. Bellinger wrote: > > On Wed, 2015-01-21 at 17:18 +0100, Bart Van Assche wrote: > >> Although several SCSI LLDs compare sc_data_direction with the value > >> DMA_BIDIRECTIONAL apparently scsi_setup_cmnd() never sets > >> sc_data_direction to the value DMA_BIDIRECTIONAL. Is this behavior on > >> purpose ? > > > > Yes. Bi-directional CDBs are signaled using scsi_bidi_cmnd(), and IIRC > > ->sc_data_direction = DMA_TO_DEVICE is set for those cases. > > But why is sc_data_direction set to DMA_BIDIRECTIONAL in > scsi_ioctl_reset() in drivers/scsi/scsi_error.c ? I think > scsi_bidi_cmnd() will return false for the SCSI command submitted by > scsi_ioctl_reset() since in this case scmd->request->next_rq == NULL. >
Well, according to DMA-API.txt it's classified as: DMA_BIDIRECTIONAL direction isn't known and is unrelated to any actual SCSI bidi commands containing both WRITE and READ payload buffers. scsi_ioctl_reset() is only generating TMFs btw, and can't inject any SCSI bidi commands. --nab -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
