ide: Add wwn support to IDE-ATAPI drive

Although it is possible to specify the wwn
property for cdrom devices on the command line,
the underlying driver fails to relay this information
to the guest operating system via IDENTIFY.

This is a simple patch to correct that.

See ATA8-ACS, Table 22 parts 5, 6, and 9.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

hw/ide/core.c

@@ -230,9 +230,23 @@ static void ide_atapi_identify(IDEState *s)
     }
 
     put_le16(p + 80, 0x1e); /* support up to ATA/ATAPI-4 */
+    if (s->wwn) {
+        put_le16(p + 84, (1 << 8)); /* supports WWN for words 108-111 */
+        put_le16(p + 87, (1 << 8)); /* WWN enabled */
+    }
+
 #ifdef USE_DMA_CDROM
     put_le16(p + 88, 0x3f | (1 << 13)); /* udma5 set and supported */
 #endif
+
+    if (s->wwn) {
+        /* LE 16-bit words 111-108 contain 64-bit World Wide Name */
+        put_le16(p + 108, s->wwn >> 48);
+        put_le16(p + 109, s->wwn >> 32);
+        put_le16(p + 110, s->wwn >> 16);
+        put_le16(p + 111, s->wwn);
+    }
+
     memcpy(s->identify_data, p, sizeof(s->identify_data));
     s->identify_set = 1;
 }