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

Igor Pylypiv
2024-06-28T23:08:18Z

On Fri, Jun 28, 2024 at 10:12:19PM +0200, Niklas Cassel wrote:
> 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.

Nice catch, Niklas! I'll fix it in v4. Thank you!

>
> 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
> >