1 files changed, 33 insertions, 35 deletions

diff --git a/hw/scsi/scsi-bus.c b/hw/scsi/scsi-bus.c
index eda8cb7e70..b901e701f0 100644
--- a/hw/scsi/scsi-bus.c
+++ b/hw/scsi/scsi-bus.c
@@ -438,19 +438,23 @@ struct SCSITargetReq {
 static void store_lun(uint8_t *outbuf, int lun)
 {
     if (lun < 256) {
+        /* Simple logical unit addressing method*/
+        outbuf[0] = 0;
         outbuf[1] = lun;
-        return;
+    } else {
+        /* Flat space addressing method */
+        outbuf[0] = 0x40 | (lun >> 8);
+        outbuf[1] = (lun & 255);
     }
-    outbuf[1] = (lun & 255);
-    outbuf[0] = (lun >> 8) | 0x40;
 }
 
 static bool scsi_target_emulate_report_luns(SCSITargetReq *r)
 {
     BusChild *kid;
-    int i, len, n;
     int channel, id;
-    bool found_lun0;
+    uint8_t tmp[8] = {0};
+    int len = 0;
+    GByteArray *buf;
 
     if (r->req.cmd.xfer < 16) {
         return false;
@@ -458,46 +462,40 @@ static bool scsi_target_emulate_report_luns(SCSITargetReq *r)
     if (r->req.cmd.buf[2] > 2) {
         return false;
     }
+
+    /* reserve space for 63 LUNs*/
+    buf = g_byte_array_sized_new(512);
+
     channel = r->req.dev->channel;
     id = r->req.dev->id;
-    found_lun0 = false;
-    n = 0;
 
-    RCU_READ_LOCK_GUARD();
+    /* add size (will be updated later to correct value */
+    g_byte_array_append(buf, tmp, 8);
+    len += 8;
 
-    QTAILQ_FOREACH_RCU(kid, &r->req.bus->qbus.children, sibling) {
-        DeviceState *qdev = kid->child;
-        SCSIDevice *dev = SCSI_DEVICE(qdev);
+    /* add LUN0 */
+    g_byte_array_append(buf, tmp, 8);
+    len += 8;
 
-        if (dev->channel == channel && dev->id == id) {
-            if (dev->lun == 0) {
-                found_lun0 = true;
+    WITH_RCU_READ_LOCK_GUARD() {
+        QTAILQ_FOREACH_RCU(kid, &r->req.bus->qbus.children, sibling) {
+            DeviceState *qdev = kid->child;
+            SCSIDevice *dev = SCSI_DEVICE(qdev);
+
+            if (dev->channel == channel && dev->id == id && dev->lun != 0) {
+                store_lun(tmp, dev->lun);
+                g_byte_array_append(buf, tmp, 8);
+                len += 8;
             }
-            n += 8;
         }
     }
-    if (!found_lun0) {
-        n += 8;
-    }
-
-    scsi_target_alloc_buf(&r->req, n + 8);
-
-    len = MIN(n + 8, r->req.cmd.xfer & ~7);
-    memset(r->buf, 0, len);
-    stl_be_p(&r->buf[0], n);
-    i = found_lun0 ? 8 : 16;
-    QTAILQ_FOREACH_RCU(kid, &r->req.bus->qbus.children, sibling) {
-        DeviceState *qdev = kid->child;
-        SCSIDevice *dev = SCSI_DEVICE(qdev);
 
-        if (dev->channel == channel && dev->id == id) {
-            store_lun(&r->buf[i], dev->lun);
-            i += 8;
-        }
-    }
+    r->buf_len = len;
+    r->buf = g_byte_array_free(buf, FALSE);
+    r->len = MIN(len, r->req.cmd.xfer & ~7);
 
-    assert(i == n + 8);
-    r->len = len;
+    /* store the LUN list length */
+    stl_be_p(&r->buf[0], len - 8);
     return true;
 }