diff mbox series

[v3,01/31] scsi: libsas: Fix sas_ata_qc_issue() handling of NCQ NON DATA commands

Message ID 20220214021747.4976-2-damien.lemoal@opensource.wdc.com
State Superseded
Headers show
Series libsas and pm8001 fixes | expand

Commit Message

Damien Le Moal Feb. 14, 2022, 2:17 a.m. UTC
To detect for the DMA_NONE (no data transfer) DMA direction,
sas_ata_qc_issue() tests if the command protocol is ATA_PROT_NODATA.
This test does not include the ATA_CMD_NCQ_NON_DATA command as this
command protocol is defined as ATA_PROT_NCQ_NODATA (equal to
ATA_PROT_FLAG_NCQ) and not as ATA_PROT_NODATA.

To include both NCQ and non-NCQ commands when testing for the DMA_NONE
DMA direction, use "!ata_is_data()".

Fixes: 176ddd89171d ("scsi: libsas: Reset num_scatter if libata marks qc as NODATA")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
---
 drivers/scsi/libsas/sas_ata.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Damien Le Moal Feb. 14, 2022, 10:23 p.m. UTC | #1
On 2/15/22 02:56, John Garry wrote:
> On 14/02/2022 02:17, Damien Le Moal wrote:
>> To detect for the DMA_NONE (no data transfer) DMA direction,
>> sas_ata_qc_issue() tests if the command protocol is ATA_PROT_NODATA.
>> This test does not include the ATA_CMD_NCQ_NON_DATA command as this
>> command protocol is defined as ATA_PROT_NCQ_NODATA (equal to
>> ATA_PROT_FLAG_NCQ) and not as ATA_PROT_NODATA.
>>
>> To include both NCQ and non-NCQ commands when testing for the DMA_NONE
>> DMA direction, use "!ata_is_data()".
>>
>> Fixes: 176ddd89171d ("scsi: libsas: Reset num_scatter if libata marks qc as NODATA")
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
> 
> Regardless of comment below:
> Reviewed-by: John Garry <john.garry@huawei.com>
> 
>> ---
>>   drivers/scsi/libsas/sas_ata.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
>> index e0030a093994..50f779088b6e 100644
>> --- a/drivers/scsi/libsas/sas_ata.c
>> +++ b/drivers/scsi/libsas/sas_ata.c
>> @@ -197,7 +197,7 @@ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
>>   		task->total_xfer_len = qc->nbytes;
>>   		task->num_scatter = qc->n_elem;
>>   		task->data_dir = qc->dma_dir;
>> -	} else if (qc->tf.protocol == ATA_PROT_NODATA) {
>> +	} else if (!ata_is_data(qc->tf.protocol)) {
> 
> I was thinking ata_is_dma() would be more appropiate, but I suppose we 
> don't have to use DMA.

That was my first thought, but using ata_is_dma() would not include PIO
case, so that would not work.

> 
>>   		task->data_dir = DMA_NONE; >   	} else {
>>   		for_each_sg(qc->sg, sg, qc->n_elem, si)
>
diff mbox series

Patch

diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
index e0030a093994..50f779088b6e 100644
--- a/drivers/scsi/libsas/sas_ata.c
+++ b/drivers/scsi/libsas/sas_ata.c
@@ -197,7 +197,7 @@  static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
 		task->total_xfer_len = qc->nbytes;
 		task->num_scatter = qc->n_elem;
 		task->data_dir = qc->dma_dir;
-	} else if (qc->tf.protocol == ATA_PROT_NODATA) {
+	} else if (!ata_is_data(qc->tf.protocol)) {
 		task->data_dir = DMA_NONE;
 	} else {
 		for_each_sg(qc->sg, sg, qc->n_elem, si)