scsi_queue_rq() memsets sense_buffer before a command is dispatched.
Libata is not memsetting sense_buffer before setting sense data that
was obtained from a disk so there should be no reason to do a memset
for ATA PASS-THROUGH / ATAPI.
Memsetting the sense_buffer in ata_gen_passthru_sense() is erasing valid
sense data that was previously obtained from a disk. A follow-up patch
will modify ata_gen_passthru_sense() to stop generating sense data based
on ATA status register bits if a valid sense data is already present.
Signed-off-by: Igor Pylypiv <ipylypiv@xxxxxxxxxx>
---
drivers/ata/libata-eh.c | 2 --
drivers/ata/libata-scsi.c | 4 ----
2 files changed, 6 deletions(-)
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 214b935c2ced..b5e05efe73f6 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -1479,8 +1479,6 @@ unsigned int atapi_eh_request_sense(struct ata_device *dev,
struct ata_port *ap = dev->link->ap;
struct ata_taskfile tf;
- memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
-
/* initialize sense_buf with the error register,
* for the case where they are -not- overwritten
*/
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index cdf29b178ddc..032cf11d0bcc 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -858,8 +858,6 @@ static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
unsigned char *desc = sb + 8;
u8 sense_key, asc, ascq;
- memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
-
/*
* Use ata_to_sense_error() to map status register bits
* onto sense key, asc & ascq.
@@ -953,8 +951,6 @@ static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
u64 block;
u8 sense_key, asc, ascq;
- memset(sb, 0, SCSI_SENSE_BUFFERSIZE);
-
if (ata_dev_disabled(dev)) {
/* Device disabled after error recovery */
/* LOGICAL UNIT NOT READY, HARD RESET REQUIRED */
--
2.45.2.627.g7a2c4fd464-goog
