Proposal Background:
SAT-4 supports ATA PASS-THROUGH(32) SCSI command to translate
SCSI commands to further ATA command format(e.g. auxiliary field).
To support any command translation from SCSI command to ATA,
This patch would be great for it.
Patch Description:
ATA PASS-THROUGH(32) command defines 7Fh as a opcode which means
a variable length command. It could be in any size from 12 to 260.
However, first to support ATA PASS-THROUGH(32), ATA Device max CDB
length has been modified to 32(It used to be 16).
Additionally, SCSI command max length has been modified to 260 to support
variable-length cdbs in kernel.
ata_get_xlat_func() adds a condition for variable length command.
ata_scsi_var_len_cdb_xlat() checks the ATA PASS-THROUGH(32) service action.
After checking, it will call ata_scsi_pass_thru() just like
ATA PASS-THROUGH(12) and (16).
ata_scsi_pass_thru() adds some code lines to support (32) pass-thru.
pass-thru(32) has a different CDB contents from 12, or 16.
Please refer below patch and fill free to give any opinions.
Thanks,
Minwoo.
Signed-off-by: Minwoo Im <dn3108@xxxxxxxxx>
---
drivers/ata/libata-core.c | 2 +-
drivers/ata/libata-scsi.c | 95 ++++++++++++++++++++++++++++++++++++++++++---
include/scsi/scsi_proto.h | 1 +
3 files changed, 91 insertions(+), 7 deletions(-)
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index e157a0e..f1d3ba4 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2587,7 +2587,7 @@ int ata_dev_configure(struct ata_device *dev)
}
ata_dev_config_sense_reporting(dev);
ata_dev_config_zac(dev);
- dev->cdb_len = 16;
+ dev->cdb_len = 32;
}
/* ATAPI-specific feature tests */
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 49ba983..b6e32d9 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3127,7 +3127,7 @@ static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
* ata_scsi_pass_thru - convert ATA pass-thru CDB to taskfile
* @qc: command structure to be initialized
*
- * Handles either 12 or 16-byte versions of the CDB.
+ * Handles either 12, 16, or 32-byte versions of the CDB.
*
* RETURNS:
* Zero on success, non-zero on failure.
@@ -3140,13 +3140,36 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
const u8 *cdb = scmd->cmnd;
u16 fp;
- if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN) {
+ /*
+ * if SCSI operation code in cdb[0] is ATA_12 or ATA_16,
+ * then cdb[1] will contain protocol of ATA PASS-THROUGH.
+ * otherwise, Its operation code shall be ATA_32(7Fh).
+ * in this case, cdb[10] will contain protocol of it.
+ * we call this command as a variable-length cdb.
+ */
+ if (cdb[0] == ATA_12 || cdb[0] == ATA_16)
+ tf->protocol = ata_scsi_map_proto(cdb[1]);
+ else
+ tf->protocol = ata_scsi_map_proto(cdb[10]);
+
+ if (tf->protocol == ATA_PROT_UNKNOWN) {
fp = 1;
goto invalid_fld;
}
- if (ata_is_ncq(tf->protocol) && (cdb[2] & 0x3) == 0)
- tf->protocol = ATA_PROT_NCQ_NODATA;
+ /*
+ * if protocol has a NCQ property and transfer length is 0,
+ * then the protocol will be marked as a NCQ_NODATA.
+ * in case of ATA_12 and ATA_16, cdb[2] has a t_length field.
+ * otherwise, cdb[11] will have a t_length field.
+ */
+ if (cdb[0] == ATA_12 || cdb[0] == ATA_16) {
+ if (ata_is_ncq(tf->protocol) && (cdb[2] & 0x3) == 0)
+ tf->protocol = ATA_PROT_NCQ_NODATA;
+ } else {
+ if (ata_is_ncq(tf->protocol) && (cdb[11] & 0x3) == 0)
+ tf->protocol = ATA_PROT_NCQ_NODATA;
+ }
/* enable LBA */
tf->flags |= ATA_TFLAG_LBA;
@@ -3181,7 +3204,7 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
tf->lbah = cdb[12];
tf->device = cdb[13];
tf->command = cdb[14];
- } else {
+ } else if (cdb[0] == ATA_12) {
/*
* 12-byte CDB - incapable of extended commands.
*/
@@ -3194,6 +3217,31 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
tf->lbah = cdb[7];
tf->device = cdb[8];
tf->command = cdb[9];
+ } else {
+ /*
+ * 32-byte CDB - may contain extended command fields.
+ *
+ * If that is the case, copy the upper byte register values.
+ */
+ if (cdb[10] & 0x01) {
+ tf->hob_feature = cdb[20];
+ tf->hob_nsect = cdb[22];
+ tf->hob_lbal = cdb[16];
+ tf->hob_lbam = cdb[15];
+ tf->hob_lbah = cdb[14];
+ tf->flags |= ATA_TFLAG_LBA48;
+ } else
+ tf->flags &= ~ATA_TFLAG_LBA48;
+
+ tf->feature = cdb[21];
+ tf->nsect = cdb[23];
+ tf->lbal = cdb[19];
+ tf->lbam = cdb[18];
+ tf->lbah = cdb[17];
+ tf->device = cdb[24];
+ tf->command = cdb[25];
+ tf->auxiliary = (cdb[28] << 24) | (cdb[29] << 16)
+ | (cdb[30] << 8) | cdb[31];
}
/* For NCQ commands copy the tag value */
@@ -4068,6 +4116,33 @@ static unsigned int ata_scsi_mode_select_xlat(struct ata_queued_cmd *qc)
}
/**
+ * ata_scsi_var_len_cdb_xlat - SATL Variable Length CDB to Handler
+ * @qc: Command to be translated
+ *
+ * Translate a SCSI variable length CDB to specified commands.
+ * It checks a service action value in CDB to call corresponding handler.
+ *
+ * RETURNS:
+ * Zero on success, non-zero on failure
+ */
+
+static unsigned int ata_scsi_var_len_cdb_xlat(struct ata_queued_cmd *qc)
+{
+ struct scsi_cmnd *scmd = qc->scsicmd;
+ const u8 *cdb = scmd->cmnd;
+ const u16 sa = (cdb[8] >> 8) | cdb[9]; /* service action */
+
+ // if service action represents a ata pass-thru(32) command,
+ // then pass it to ata_scsi_pass_thru handler.
+ if (sa == ATA_32)
+ return ata_scsi_pass_thru(qc);
+
+unspprt_sa:
+ /* unsupported service action */
+ return 1;
+}
+
+/**
* ata_get_xlat_func - check if SCSI to ATA translation is possible
* @dev: ATA device
* @cmd: SCSI command opcode to consider
@@ -4107,6 +4182,9 @@ static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
case ATA_16:
return ata_scsi_pass_thru;
+ case VARIABLE_LENGTH_CMD:
+ return ata_scsi_var_len_cdb_xlat;
+
case MODE_SELECT:
case MODE_SELECT_10:
return ata_scsi_mode_select_xlat;
@@ -4385,7 +4463,12 @@ int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht)
shost->max_id = 16;
shost->max_lun = 1;
shost->max_channel = 1;
- shost->max_cmd_len = 16;
+ /*
+ * SPC-3, SPC-4: Definition of CDB
+ * A CDB may have a fixed length of up to 16 bytes or
+ * variable length of between 12 and 260 bytes.
+ */
+ shost->max_cmd_len = 260;
/* Schedule policy is determined by ->qc_defer()
* callback and it needs to see every deferred qc.
diff --git a/include/scsi/scsi_proto.h b/include/scsi/scsi_proto.h
index ce78ec8..8545e34 100644
--- a/include/scsi/scsi_proto.h
+++ b/include/scsi/scsi_proto.h
@@ -164,6 +164,7 @@
#define WRITE_SAME_32 0x0d
/* Values for T10/04-262r7 */
+#define ATA_32 0x1ff0 /* 32-byte pass-thru, service action */
#define ATA_16 0x85 /* 16-byte pass-thru */
#define ATA_12 0xa1 /* 12-byte pass-thru */
--
1.7.9.5
