[PATCH 4.19 039/338] scsi: libsas: Fix sas_ata_qc_issue() handling of NCQ NON DATA commands

From: Greg Kroah-Hartman
Date: Thu Apr 14 2022 - 09:18:11 EST


From: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>

commit 8454563e4c2aafbfb81a383ab423ea8b9b430a25 upstream.

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()".

Link: https://lore.kernel.org/r/20220220031810.738362-2-damien.lemoal@xxxxxxxxxxxxxxxxxx
Fixes: 176ddd89171d ("scsi: libsas: Reset num_scatter if libata marks qc as NODATA")
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: John Garry <john.garry@xxxxxxxxxx>
Reviewed-by: Jack Wang <jinpu.wang@xxxxxxxxx>
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/scsi/libsas/sas_ata.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/scsi/libsas/sas_ata.c
+++ b/drivers/scsi/libsas/sas_ata.c
@@ -216,7 +216,7 @@ static unsigned int sas_ata_qc_issue(str
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)