diff options
| author | Nicholas Bellinger <nab@linux-iscsi.org> | 2014-06-06 03:27:53 +0400 |
|---|---|---|
| committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2014-06-07 01:20:23 +0400 |
| commit | b3e5fe1688b998ba5287a68667ef7cc568739e44 (patch) | |
| tree | 5d7a9999d5cfc92ff4cd4ccc50d1ebea95f41334 /drivers/target | |
| parent | 1d2b60a5545942b1376cb48c1d55843d71e3a08f (diff) | |
| download | linux-b3e5fe1688b998ba5287a68667ef7cc568739e44.tar.xz | |
tcm_fc: Generate TASK_SET_FULL status for DataIN failures
This patch changes ft_queue_data_in() to set SAM_STAT_TASK_SET_FULL
status upon a lport->tt.seq_send() failure, where it will now stop
sending subsequent DataIN, and immediately attempt to send the
response with exception status.
Sending a response with SAM_STAT_TASK_SET_FULL status is useful in
order to signal the initiator that it should try to reduce it's
current queue_depth, to lower the number of outstanding I/Os on
the wire.
Also, add a check to skip sending DataIN if TASK_SET_FULL status
has already been set due to a response lport->tt.seq_send()
failure, that has asked target-core to requeue a response.
Reported-by: Vasu Dev <vasu.dev@linux.intel.com>
Reviewed-by: Vasu Dev <vasu.dev@linux.intel.com>
Cc: Jun Wu <jwu@stormojo.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'drivers/target')
| -rw-r--r-- | drivers/target/tcm_fc/tfc_io.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/drivers/target/tcm_fc/tfc_io.c b/drivers/target/tcm_fc/tfc_io.c index e415af32115a..97b486c3dda1 100644 --- a/drivers/target/tcm_fc/tfc_io.c +++ b/drivers/target/tcm_fc/tfc_io.c @@ -82,6 +82,10 @@ int ft_queue_data_in(struct se_cmd *se_cmd) if (cmd->aborted) return 0; + + if (se_cmd->scsi_status == SAM_STAT_TASK_SET_FULL) + goto queue_status; + ep = fc_seq_exch(cmd->seq); lport = ep->lp; cmd->seq = lport->tt.seq_start_next(cmd->seq); @@ -178,14 +182,23 @@ int ft_queue_data_in(struct se_cmd *se_cmd) FC_TYPE_FCP, f_ctl, fh_off); error = lport->tt.seq_send(lport, seq, fp); if (error) { - /* XXX For now, initiator will retry */ - pr_err_ratelimited("%s: Failed to send frame %p, " + pr_info_ratelimited("%s: Failed to send frame %p, " "xid <0x%x>, remaining %zu, " "lso_max <0x%x>\n", __func__, fp, ep->xid, remaining, lport->lso_max); + /* + * Go ahead and set TASK_SET_FULL status ignoring the + * rest of the DataIN, and immediately attempt to + * send the response via ft_queue_status() in order + * to notify the initiator that it should reduce it's + * per LUN queue_depth. + */ + se_cmd->scsi_status = SAM_STAT_TASK_SET_FULL; + break; } } +queue_status: return ft_queue_status(se_cmd); } |