libata: Support for an ATA PASS-THROUGH(32) command.

SAT-4(SCSI/ATA Translation) supports for an ata pass-thru(32).
This patch will allow to translate an ata pass-thru(32) SCSI cmd
to an ATA cmd.

Signed-off-by: Minwoo Im <dn3108@gmail.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

2 files changed, 68 insertions, 6 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index a846c29f3248..d1b2c6b5f680 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2661,7 +2661,7 @@ int ata_dev_configure(struct ata_device *dev)
                 ata_dev_config_sense_reporting(dev);
                 ata_dev_config_zac(dev);
                 ata_dev_config_trusted(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 4c300749aca5..815c6e240aea 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3126,7 +3126,7 @@ ata_scsi_map_proto(u8 byte1)
  *      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.
@@ -3138,13 +3138,19 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
         struct ata_device *dev = qc->dev;
         const u8 *cdb = scmd->cmnd;
         u16 fp;
+        u16 cdb_offset = 0;
 
-        if ((tf->protocol = ata_scsi_map_proto(cdb[1])) == ATA_PROT_UNKNOWN) {
+        /* 7Fh variable length cmd means a ata pass-thru(32) */
+        if (cdb[0] == VARIABLE_LENGTH_CMD)
+                cdb_offset = 9;
+
+        tf->protocol = ata_scsi_map_proto(cdb[1 + cdb_offset]);
+        if (tf->protocol == ATA_PROT_UNKNOWN) {
                 fp = 1;
                 goto invalid_fld;
         }
 
-        if (ata_is_ncq(tf->protocol) && (cdb[2] & 0x3) == 0)
+        if (ata_is_ncq(tf->protocol) && (cdb[2 + cdb_offset] & 0x3) == 0)
                 tf->protocol = ATA_PROT_NCQ_NODATA;
 
         /* enable LBA */
@@ -3180,7 +3186,7 @@ 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.
                  */
@@ -3193,6 +3199,30 @@ 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 = get_unaligned_be32(&cdb[28]);
         }
 
         /* For NCQ commands copy the tag value */
@@ -4138,6 +4168,35 @@ static unsigned int ata_scsi_security_inout_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 = get_unaligned_be16(&cdb[8]);
+
+        /*
+         * 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
@@ -4177,6 +4236,9 @@ 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;
@@ -4461,7 +4523,7 @@ 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;
+                shost->max_cmd_len = 32;
 
                 /* Schedule policy is determined by ->qc_defer()
                  * callback and it needs to see every deferred qc.