On 9/20/21 2:42 AM, John Garry wrote:

On 18/09/2021 01:04, Bart Van Assche wrote:

quoted

@@ -1692,7 +1693,7 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,

      scsi_set_resid(cmd, 0);
      memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
-    cmd->scsi_done = scsi_mq_done;
+    cmd->scsi_done = scsi_done;

I have gone to the end of the series, and we still set scsi_cmnd.scsi_done. So some drivers still rely on it. I thought that the idea was that we don't need this callback pointer any longer.

It seems like the email service I used to send out the patches (gmail)
dropped patches 79/84..84/84. The entire patch series is available here:
https://github.com/bvanassche/linux/tree/scsi-remove-done-callback

Patch 84/84 includes the following change:

  @@ -1693,7 +1693,6 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx,

  	scsi_set_resid(cmd, 0);
  	memset(cmd->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
-	cmd->scsi_done = scsi_done;

  	blk_mq_start_request(req);
  	reason = scsi_dispatch_cmd(cmd);

As an aside, this is the current declaration of scsi_cmnd.scsi_done:

/* Low-level done function - can be used by low-level driver to point
*        to completion function.  Not used by mid/upper level code. */
     void (*scsi_done) (struct scsi_cmnd *);

That does not sound right, as scsi_done is set by the mid-layer.

"Not used" probably should have been "not called". Anyway, patch 84/84
removes that function pointer and also the comment above that function
pointer.

Thanks,

Bart.