[GIT PULL] SCSI fixes for 6.6-rc3

[James Bottomley]

Single fix for libata: older devices don't support command duration
limits (CDL) and some don't support report opcodes, meaning there's no
way to tell if they support the command or not. Reduce the problems of
incorrectly using CDL commands on older devices by checking SCSI spec
compliance at SPC-5 (the spec which introduced the command) before
turning on CDL.

The patch is available here:

git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi.git scsi-fixes

The short changelog is:

Damien Le Moal (1):
      scsi: core: ata: Do no try to probe for CDL on old drives

And the diffstat:

 drivers/ata/libata-scsi.c |  3 +++
 drivers/scsi/scsi.c       | 11 +++++++++++
 drivers/scsi/scsi_scan.c  |  2 +-
 include/scsi/scsi.h       |  3 +++
 4 files changed, 18 insertions(+), 1 deletion(-)

With full diff below.

James

---

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index d3f28b82c97b..0e96ed408c71 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -1835,6 +1835,9 @@ static unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf)
 		hdr[2] = 0x7; /* claim SPC-5 version compatibility */
 	}
 
+	if (args->dev->flags & ATA_DFLAG_CDL)
+		hdr[2] = 0xd; /* claim SPC-6 version compatibility */
+
 	memcpy(rbuf, hdr, sizeof(hdr));
 	memcpy(&rbuf[8], "ATA     ", 8);
 	ata_id_string(args->id, &rbuf[16], ATA_ID_PROD, 16);
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index d0911bc28663..89367c4bf0ef 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -613,6 +613,17 @@ void scsi_cdl_check(struct scsi_device *sdev)
 	bool cdl_supported;
 	unsigned char *buf;
 
+	/*
+	 * Support for CDL was defined in SPC-5. Ignore devices reporting an
+	 * lower SPC version. This also avoids problems with old drives choking
+	 * on MAINTENANCE_IN / MI_REPORT_SUPPORTED_OPERATION_CODES with a
+	 * service action specified, as done in scsi_cdl_check_cmd().
+	 */
+	if (sdev->scsi_level < SCSI_SPC_5) {
+		sdev->cdl_supported = 0;
+		return;
+	}
+
 	buf = kmalloc(SCSI_CDL_CHECK_BUF_LEN, GFP_KERNEL);
 	if (!buf) {
 		sdev->cdl_supported = 0;
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 52014b2d39e1..eaa972bee6c0 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -822,7 +822,7 @@ static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
 	 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
 	 * non-zero LUNs can be scanned.
 	 */
-	sdev->scsi_level = inq_result[2] & 0x07;
+	sdev->scsi_level = inq_result[2] & 0x0f;
 	if (sdev->scsi_level >= 2 ||
 	    (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
 		sdev->scsi_level++;
diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h
index ec093594ba53..4498f845b112 100644
--- a/include/scsi/scsi.h
+++ b/include/scsi/scsi.h
@@ -157,6 +157,9 @@ enum scsi_disposition {
 #define SCSI_3          4        /* SPC */
 #define SCSI_SPC_2      5
 #define SCSI_SPC_3      6
+#define SCSI_SPC_4	7
+#define SCSI_SPC_5	8
+#define SCSI_SPC_6	14
 
 /*
  * INQ PERIPHERAL QUALIFIERS