Re: [PATCH v3 5/6] ata: libata: Set ATA_QCFLAG_RTF_FILLED in fill_result_tf()

Niklas Cassel
2024-06-28T20:12:23Z

On Wed, Jun 26, 2024 at 11:04:10PM +0000, Igor Pylypiv wrote:
> 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>
> Signed-off-by: Igor Pylypiv <ipylypiv@google.com>
> ---
> drivers/ata/libahci.c | 10 ----------
> drivers/ata/libata-core.c | 8 ++++++++
> 2 files changed, 8 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
> index 83431aae74d8..0728d445e531 100644
> --- a/drivers/ata/libahci.c
> +++ b/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)
> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
> index e1bf8a19b3c8..a9fc3ec9300f 100644
> --- a/drivers/ata/libata-core.c
> +++ b/drivers/ata/libata-core.c
> @@ -4801,8 +4801,16 @@ 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;

One functional change that I can see from this is that after this commit,
we will no longer do: qc->result_tf.flags = qc->tf.flags;
if ATA_QCFLAG_RTF_FILLED was set.

e.g. ata_scsi_set_passthru_sense_fields() and ata_gen_ata_sense()
makes use of result_tf->flags, so we probably still want to do this.

Perhaps keep this function as you have it and simply do:

diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index 0728d445e531..fdfa7b266218 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -2148,6 +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);
@@ -2172,6 +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);

> ap->ops->qc_fill_rtf(qc);
> + qc->flags |= ATA_QCFLAG_RTF_FILLED;
> }
>
> static void ata_verify_xfer(struct ata_queued_cmd *qc)
> --
> 2.45.2.803.g4e1b14247a-goog
>