libata: make ata_eh_qc_retry() bump scmd->allowed on bogus failures

libata EH decrements scmd->retries when the command failed for reasons
unrelated to the command itself so that, for example, commands aborted
due to suspend / resume cycle don't get penalized; however,
decrementing scmd->retries isn't enough for ATA passthrough commands.

Without this fix, ATA passthrough commands are not resend to the
drive, and no error is signalled to the caller because:

- allowed retry count is 1
- ata_eh_qc_complete fill the sense data, so result is valid
- sense data is filled with untouched ATA registers.

Signed-off-by: Gwendal Grignou <gwendal@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index c69fcce505c0..370462fa8e01 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -1322,14 +1322,14 @@ void ata_eh_qc_complete(struct ata_queued_cmd *qc)
  *      should be retried.  To be used from EH.
  *
  *      SCSI midlayer limits the number of retries to scmd->allowed.
- *      scmd->retries is decremented for commands which get retried
+ *      scmd->allowed is incremented for commands which get retried
  *      due to unrelated failures (qc->err_mask is zero).
  */
 void ata_eh_qc_retry(struct ata_queued_cmd *qc)
 {
         struct scsi_cmnd *scmd = qc->scsicmd;
-        if (!qc->err_mask && scmd->retries)
-                scmd->retries--;
+        if (!qc->err_mask)
+                scmd->allowed++;
         __ata_eh_qc_complete(qc);
 }