libata: Implement NCQ autosense

Some newer devices support NCQ autosense (cf ACS-4), so we should
be using it to retrieve the sense code and speed up recovery.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

3 files changed, 26 insertions, 2 deletions

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 50ffd4e98978..c9b19949708c 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -1580,6 +1580,8 @@ static int ata_eh_read_log_10h(struct ata_device *dev,
         tf->hob_lbah = buf[10];
         tf->nsect = buf[12];
         tf->hob_nsect = buf[13];
+        if (ata_id_has_ncq_autosense(dev->id))
+                tf->auxiliary = buf[14] << 16 | buf[15] << 8 | buf[16];
 
         return 0;
 }
@@ -1777,6 +1779,18 @@ void ata_eh_analyze_ncq_error(struct ata_link *link)
         memcpy(&qc->result_tf, &tf, sizeof(tf));
         qc->result_tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
         qc->err_mask |= AC_ERR_DEV | AC_ERR_NCQ;
+        if (qc->result_tf.auxiliary) {
+                char sense_key, asc, ascq;
+
+                sense_key = (qc->result_tf.auxiliary >> 16) & 0xff;
+                asc = (qc->result_tf.auxiliary >> 8) & 0xff;
+                ascq = qc->result_tf.auxiliary & 0xff;
+                ata_dev_dbg(dev, "NCQ Autosense %02x/%02x/%02x\n",
+                            sense_key, asc, ascq);
+                ata_scsi_set_sense(qc->scsicmd, sense_key, asc, ascq);
+                qc->flags |= ATA_QCFLAG_SENSE_VALID;
+        }
+
         ehc->i.err_mask &= ~AC_ERR_DEV;
 }
 
@@ -1806,6 +1820,10 @@ static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc,
                 return ATA_EH_RESET;
         }
 
+        /* Set by NCQ autosense */
+        if (qc->flags & ATA_QCFLAG_SENSE_VALID)
+                return 0;
+
         if (stat & (ATA_ERR | ATA_DF))
                 qc->err_mask |= AC_ERR_DEV;
         else
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index bb57d81083ca..3ac5be3acdbe 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -270,8 +270,11 @@ DEVICE_ATTR(unload_heads, S_IRUGO | S_IWUSR,
             ata_scsi_park_show, ata_scsi_park_store);
 EXPORT_SYMBOL_GPL(dev_attr_unload_heads);
 
-static void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
+void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq)
 {
+        if (!cmd)
+                return;
+
         cmd->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION;
 
         scsi_build_sense_buffer(0, cmd->sense_buffer, sk, asc, ascq);
@@ -1777,7 +1780,9 @@ static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
             ((cdb[2] & 0x20) || need_sense)) {
                 ata_gen_passthru_sense(qc);
         } else {
-                if (!need_sense) {
+                if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
+                        cmd->result = SAM_STAT_CHECK_CONDITION;
+                } else if (!need_sense) {
                         cmd->result = SAM_STAT_GOOD;
                 } else {
                         /* TODO: decide which descriptor format to use
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index f840ca18a7c0..8cfdd9616d16 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -137,6 +137,7 @@ extern int ata_scsi_add_hosts(struct ata_host *host,
                               struct scsi_host_template *sht);
 extern void ata_scsi_scan_host(struct ata_port *ap, int sync);
 extern int ata_scsi_offline_dev(struct ata_device *dev);
+extern void ata_scsi_set_sense(struct scsi_cmnd *cmd, u8 sk, u8 asc, u8 ascq);
 extern void ata_scsi_media_change_notify(struct ata_device *dev);
 extern void ata_scsi_hotplug(struct work_struct *work);
 extern void ata_schedule_scsi_eh(struct Scsi_Host *shost);