ata: libata-core: Set ATA_QCFLAG_RTF_FILLED in fill_result_tf()

ATA_QCFLAG_RTF_FILLED is not specific to ahci and can be used generally
to check if qc->result_tf contains valid data.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Igor Pylypiv <ipylypiv@google.com>
Link: https://lore.kernel.org/r/20240702024735.1152293-7-ipylypiv@google.com
Signed-off-by: Niklas Cassel <cassel@kernel.org>

Author: ipylypiv

drivers/ata/libahci.c

@@ -2075,13 +2075,6 @@ static void ahci_qc_fill_rtf(struct ata_queued_cmd *qc)
 	struct ahci_port_priv *pp = qc->ap->private_data;
 	u8 *rx_fis = pp->rx_fis;
 
-	/*
-	 * rtf may already be filled (e.g. for successful NCQ commands).
-	 * If that is the case, we have nothing to do.
-	 */
-	if (qc->flags & ATA_QCFLAG_RTF_FILLED)
-		return;
-
 	if (pp->fbs_enabled)
 		rx_fis += qc->dev->link->pmp * AHCI_RX_FIS_SZ;
 
@@ -2095,7 +2088,6 @@ static void ahci_qc_fill_rtf(struct ata_queued_cmd *qc)
 	    !(qc->flags & ATA_QCFLAG_EH)) {
 		ata_tf_from_fis(rx_fis + RX_FIS_PIO_SETUP, &qc->result_tf);
 		qc->result_tf.status = (rx_fis + RX_FIS_PIO_SETUP)[15];
-		qc->flags |= ATA_QCFLAG_RTF_FILLED;
 		return;
 	}
 
@@ -2118,12 +2110,10 @@ static void ahci_qc_fill_rtf(struct ata_queued_cmd *qc)
 		 */
 		qc->result_tf.status = fis[2];
 		qc->result_tf.error = fis[3];
-		qc->flags |= ATA_QCFLAG_RTF_FILLED;
 		return;
 	}
 
 	ata_tf_from_fis(rx_fis + RX_FIS_D2H_REG, &qc->result_tf);
-	qc->flags |= ATA_QCFLAG_RTF_FILLED;
 }
 
 static void ahci_qc_ncq_fill_rtf(struct ata_port *ap, u64 done_mask)
@@ -2158,6 +2148,7 @@ static void ahci_qc_ncq_fill_rtf(struct ata_port *ap, u64 done_mask)
 			if (qc && ata_is_ncq(qc->tf.protocol)) {
 				qc->result_tf.status = status;
 				qc->result_tf.error = error;
+				qc->result_tf.flags = qc->tf.flags;
 				qc->flags |= ATA_QCFLAG_RTF_FILLED;
 			}
 			done_mask &= ~(1ULL << tag);
@@ -2182,6 +2173,7 @@ static void ahci_qc_ncq_fill_rtf(struct ata_port *ap, u64 done_mask)
 			fis += RX_FIS_SDB;
 			qc->result_tf.status = fis[2];
 			qc->result_tf.error = fis[3];
+			qc->result_tf.flags = qc->tf.flags;
 			qc->flags |= ATA_QCFLAG_RTF_FILLED;
 		}
 		done_mask &= ~(1ULL << tag);

drivers/ata/libata-core.c

@@ -4794,8 +4794,16 @@ static void fill_result_tf(struct ata_queued_cmd *qc)
 {
 	struct ata_port *ap = qc->ap;
 
+	/*
+	 * rtf may already be filled (e.g. for successful NCQ commands).
+	 * If that is the case, we have nothing to do.
+	 */
+	if (qc->flags & ATA_QCFLAG_RTF_FILLED)
+		return;
+
 	qc->result_tf.flags = qc->tf.flags;
 	ap->ops->qc_fill_rtf(qc);
+	qc->flags |= ATA_QCFLAG_RTF_FILLED;
 }
 
 static void ata_verify_xfer(struct ata_queued_cmd *qc)