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Date: Fri, 14 Jun 2024 19:18:35 +0000
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Subject: [PATCH v1 4/4] ata: libata-scsi: Fix offsets for the fixed format
 sense data
From: Igor Pylypiv <ipylypiv@google.com>
To: Damien Le Moal <dlemoal@kernel.org>, Niklas Cassel <cassel@kernel.org>
Cc: Tejun Heo <tj@kernel.org>, Hannes Reinecke <hare@suse.de>, linux-ide@vger.kernel.org, 
	linux-kernel@vger.kernel.org, Igor Pylypiv <ipylypiv@google.com>, 
	Akshat Jain <akshatzen@google.com>
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Correct the ATA PASS-THROUGH fixed format sense data offsets to conform
to SPC-6 and SAT-5 specifications. Additionally, set the VALID bit to
indicate that the INFORMATION field contains valid information.

INFORMATION
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D

SAT-5 Table 212 =E2=80=94 "Fixed format sense data INFORMATION field for th=
e ATA
PASS-THROUGH commands" defines the following format:

+------+------------+
| Byte |   Field    |
+------+------------+
|    0 | ERROR      |
|    1 | STATUS     |
|    2 | DEVICE     |
|    3 | COUNT(7:0) |
+------+------------+

SPC-6 Table 48 - "Fixed format sense data" specifies that the INFORMATION
field starts at byte 3 in sense buffer resulting in the following offsets
for the ATA PASS-THROUGH commands:

+------------+-------------------------+
|   Field    |  Offset in sense buffer |
+------------+-------------------------+
| ERROR      |  3                      |
| STATUS     |  4                      |
| DEVICE     |  5                      |
| COUNT(7:0) |  6                      |
+------------+-------------------------+

COMMAND-SPECIFIC INFORMATION
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D

SAT-5 Table 213 - "Fixed format sense data COMMAND-SPECIFIC INFORMATION
field for ATA PASS-THROUGH" defines the following format:

+------+-------------------+
| Byte |        Field      |
+------+-------------------+
|    0 | FLAGS | LOG INDEX |
|    1 | LBA (7:0)         |
|    2 | LBA (15:8)        |
|    3 | LBA (23:16)       |
+------+-------------------+

SPC-6 Table 48 - "Fixed format sense data" specifies that
the COMMAND-SPECIFIC-INFORMATION field starts at byte 8
in sense buffer resulting in the following offsets for
the ATA PASS-THROUGH commands:

Offsets of these fields in the fixed sense format are as follows:

+-------------------+-------------------------+
|       Field       |  Offset in sense buffer |
+-------------------+-------------------------+
| FLAGS | LOG INDEX |  8                      |
| LBA (7:0)         |  9                      |
| LBA (15:8)        |  10                     |
| LBA (23:16)       |  11                     |
+-------------------+-------------------------+

Reported-by: Akshat Jain <akshatzen@google.com>
Fixes: 11093cb1ef56 ("libata-scsi: generate correct ATA pass-through sense"=
)
Signed-off-by: Igor Pylypiv <ipylypiv@google.com>
---
 drivers/ata/libata-scsi.c | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 4bfe47e7d266..8588512f5975 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -855,7 +855,6 @@ static void ata_gen_passthru_sense(struct ata_queued_cm=
d *qc)
 	struct scsi_cmnd *cmd =3D qc->scsicmd;
 	struct ata_taskfile *tf =3D &qc->result_tf;
 	unsigned char *sb =3D cmd->sense_buffer;
-	unsigned char *desc =3D sb + 8;
 	u8 sense_key, asc, ascq;
=20
 	if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
@@ -880,8 +879,9 @@ static void ata_gen_passthru_sense(struct ata_queued_cm=
d *qc)
 		scsi_build_sense(cmd, 1, RECOVERED_ERROR, 0, 0x1D);
 	}
=20
-	if ((cmd->sense_buffer[0] & 0x7f) >=3D 0x72) {
+	if ((sb[0] & 0x7f) >=3D 0x72) {
 		u8 len;
+		unsigned char *desc;
=20
 		/* descriptor format */
 		len =3D sb[7];
@@ -919,21 +919,21 @@ static void ata_gen_passthru_sense(struct ata_queued_=
cmd *qc)
 		}
 	} else {
 		/* Fixed sense format */
-		desc[0] =3D tf->error;
-		desc[1] =3D tf->status;
-		desc[2] =3D tf->device;
-		desc[3] =3D tf->nsect;
-		desc[7] =3D 0;
+		sb[0] |=3D 0x80;
+		sb[3] =3D tf->error;
+		sb[4] =3D tf->status;
+		sb[5] =3D tf->device;
+		sb[6] =3D tf->nsect;
 		if (tf->flags & ATA_TFLAG_LBA48)  {
-			desc[8] |=3D 0x80;
+			sb[8] |=3D 0x80;
 			if (tf->hob_nsect)
-				desc[8] |=3D 0x40;
+				sb[8] |=3D 0x40;
 			if (tf->hob_lbal || tf->hob_lbam || tf->hob_lbah)
-				desc[8] |=3D 0x20;
+				sb[8] |=3D 0x20;
 		}
-		desc[9] =3D tf->lbal;
-		desc[10] =3D tf->lbam;
-		desc[11] =3D tf->lbah;
+		sb[9] =3D tf->lbal;
+		sb[10] =3D tf->lbam;
+		sb[11] =3D tf->lbah;
 	}
 }
=20
--=20
2.45.2.627.g7a2c4fd464-goog