scsi: Add basic support for SCSI media changer commands.

This adds basic support for SCSI media changer commands.
Not all commands are supported as of now, but enough to cover
basic functionality.

Signed-off-by: Christian Hoff <christian.hoff@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

2 files changed, 43 insertions, 6 deletions

diff --git a/hw/scsi-bus.c b/hw/scsi-bus.c
index 4ec9b52c7d..9c64e30279 100644
--- a/hw/scsi-bus.c
+++ b/hw/scsi-bus.c
@@ -770,7 +770,6 @@ static int scsi_req_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
     case SET_CD_SPEED:
     case SET_LIMITS:
     case WRITE_LONG_10:
-    case MOVE_MEDIUM:
     case UPDATE_BLOCK:
     case RESERVE_TRACK:
     case SET_READ_AHEAD:
@@ -914,6 +913,29 @@ static int scsi_req_stream_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *bu
     return 0;
 }
 
+static int scsi_req_medium_changer_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
+{
+    switch (buf[0]) {
+    /* medium changer commands */
+    case EXCHANGE_MEDIUM:
+    case INITIALIZE_ELEMENT_STATUS:
+    case INITIALIZE_ELEMENT_STATUS_WITH_RANGE:
+    case MOVE_MEDIUM:
+    case POSITION_TO_ELEMENT:
+        cmd->xfer = 0;
+        break;
+    case READ_ELEMENT_STATUS:
+        cmd->xfer = buf[9] | (buf[8] << 8) | (buf[7] << 16);
+        break;
+
+    /* generic commands */
+    default:
+        return scsi_req_length(cmd, dev, buf);
+    }
+    return 0;
+}
+
+
 static void scsi_cmd_xfer_mode(SCSICommand *cmd)
 {
     if (!cmd->xfer) {
@@ -1011,11 +1033,18 @@ int scsi_req_parse(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
         return -1;
     }
 
-    if (dev->type == TYPE_TAPE) {
+    switch (dev->type) {
+    case TYPE_TAPE:
         rc = scsi_req_stream_length(cmd, dev, buf);
-    } else {
+        break;
+    case TYPE_MEDIUM_CHANGER:
+        rc = scsi_req_medium_changer_length(cmd, dev, buf);
+        break;
+    default:
         rc = scsi_req_length(cmd, dev, buf);
+        break;
     }
+
     if (rc != 0)
         return rc;
 
@@ -1193,7 +1222,8 @@ static const char *scsi_command_name(uint8_t cmd)
         [ REQUEST_SENSE            ] = "REQUEST_SENSE",
         [ FORMAT_UNIT              ] = "FORMAT_UNIT",
         [ READ_BLOCK_LIMITS        ] = "READ_BLOCK_LIMITS",
-        [ REASSIGN_BLOCKS          ] = "REASSIGN_BLOCKS",
+        [ REASSIGN_BLOCKS          ] = "REASSIGN_BLOCKS/INITIALIZE ELEMENT STATUS",
+        /* LOAD_UNLOAD and INITIALIZE_ELEMENT_STATUS use the same operation code */
         [ READ_6                   ] = "READ_6",
         [ WRITE_6                  ] = "WRITE_6",
         [ SET_CAPACITY             ] = "SET_CAPACITY",
@@ -1218,7 +1248,8 @@ static const char *scsi_command_name(uint8_t cmd)
         [ READ_CAPACITY_10         ] = "READ_CAPACITY_10",
         [ READ_10                  ] = "READ_10",
         [ WRITE_10                 ] = "WRITE_10",
-        [ SEEK_10                  ] = "SEEK_10",
+        [ SEEK_10                  ] = "SEEK_10/POSITION_TO_ELEMENT",
+        /* SEEK_10 and POSITION_TO_ELEMENT use the same operation code */
         [ WRITE_VERIFY_10          ] = "WRITE_VERIFY_10",
         [ VERIFY_10                ] = "VERIFY_10",
         [ SEARCH_HIGH              ] = "SEARCH_HIGH",
@@ -1229,7 +1260,8 @@ static const char *scsi_command_name(uint8_t cmd)
         /* READ_POSITION and PRE_FETCH use the same operation code */
         [ SYNCHRONIZE_CACHE        ] = "SYNCHRONIZE_CACHE",
         [ LOCK_UNLOCK_CACHE        ] = "LOCK_UNLOCK_CACHE",
-        [ READ_DEFECT_DATA         ] = "READ_DEFECT_DATA",
+        [ READ_DEFECT_DATA         ] = "READ_DEFECT_DATA/INITIALIZE_ELEMENT_STATUS_WITH_RANGE",
+        /* READ_DEFECT_DATA and INITIALIZE_ELEMENT_STATUS_WITH_RANGE use the same operation code */
         [ MEDIUM_SCAN              ] = "MEDIUM_SCAN",
         [ COMPARE                  ] = "COMPARE",
         [ COPY_VERIFY              ] = "COPY_VERIFY",
@@ -1274,6 +1306,7 @@ static const char *scsi_command_name(uint8_t cmd)
         [ REPORT_LUNS              ] = "REPORT_LUNS",
         [ BLANK                    ] = "BLANK",
         [ MOVE_MEDIUM              ] = "MOVE_MEDIUM",
+        [ EXCHANGE_MEDIUM          ] = "EXCHANGE MEDIUM",
         [ LOAD_UNLOAD              ] = "LOAD_UNLOAD",
         [ READ_12                  ] = "READ_12",
         [ WRITE_12                 ] = "WRITE_12",
diff --git a/hw/scsi-defs.h b/hw/scsi-defs.h
index 6578bb9950..ade82a488f 100644
--- a/hw/scsi-defs.h
+++ b/hw/scsi-defs.h
@@ -29,6 +29,7 @@
 #define REQUEST_SENSE         0x03
 #define FORMAT_UNIT           0x04
 #define READ_BLOCK_LIMITS     0x05
+#define INITIALIZE_ELEMENT_STATUS 0x07
 #define REASSIGN_BLOCKS       0x07
 #define READ_6                0x08
 #define WRITE_6               0x0a
@@ -54,6 +55,7 @@
 #define WRITE_10              0x2a
 #define SEEK_10               0x2b
 #define LOCATE_10             0x2b
+#define POSITION_TO_ELEMENT   0x2b
 #define WRITE_VERIFY_10       0x2e
 #define VERIFY_10             0x2f
 #define SEARCH_HIGH           0x30
@@ -64,6 +66,7 @@
 #define READ_POSITION         0x34
 #define SYNCHRONIZE_CACHE     0x35
 #define LOCK_UNLOCK_CACHE     0x36
+#define INITIALIZE_ELEMENT_STATUS_WITH_RANGE 0x37
 #define READ_DEFECT_DATA      0x37
 #define MEDIUM_SCAN           0x38
 #define COMPARE               0x39
@@ -118,6 +121,7 @@
 #define MAINTENANCE_IN        0xa3
 #define MAINTENANCE_OUT       0xa4
 #define MOVE_MEDIUM           0xa5
+#define EXCHANGE_MEDIUM       0xa6
 #define SET_READ_AHEAD        0xa7
 #define READ_12               0xa8
 #define WRITE_12              0xaa