Changeset 32225 in vbox for trunk/src/VBox

Timestamp:

Sep 2, 2010 8:07:53 PM (14 years ago)

Author:

vboxsync

Message:

iSCSI: Don't send more PDUs then allowed by the target. The MaxCmdSN parameter gives the maximum command sequence number it allows

File:

• trunk/src/VBox/Devices/Storage/ISCSIHDDCore.cpp (modified) (6 diffs)

trunk/src/VBox/Devices/Storage/ISCSIHDDCore.cpp

@@ -475 +475 @@
     /** The BHS. */
     uint32_t    aBHS[12];
+    /** Assigned CmdSN for this PDU. */
+    uint32_t    CmdSN;
     /** The S/G buffer used for sending. */
     RTSGBUF     SgBuf;
@@ -690 +692 @@
 /* Serial number arithmetic comparison. */
 static bool serial_number_less(uint32_t sn1, uint32_t sn2);
+static bool serial_number_greater(uint32_t sn1, uint32_t sn2);
 
 /* CHAP-MD5 functions. */
@@ -2295 +2298 @@
     do
     {
-        /* If there is no PDU active, get the first one from the list. */
+        /*
+         * If there is no PDU active, get the first one from the list.
+         * Check that we are allowed to transfer the PDU by comparing the
+         * command sequence number and the maximum sequence number allowed by the target.
+         */
         if (!pImage->pIScsiPDUTxCur)
         {
-            if (!pImage->pIScsiPDUTxHead)
+            if (   !pImage->pIScsiPDUTxHead
+                || serial_number_greater(pImage->pIScsiPDUTxHead->CmdSN, pImage->MaxCmdSN))
                 break;
 
@@ -2417 +2425 @@
                  */
                 rc = iscsiRecvPDUUpdateRequest(pImage, paRes, cnRes);
+                /* Try to send more PDUs now that we updated the MaxCmdSN field */
+                if (   RT_SUCCESS(rc)
+                    && !pImage->pIScsiPDUTxCur)
+                    rc = iscsiSendPDUAsync(pImage);
             }
             else
@@ -2619 +2631 @@
     paReqBHS[7] = RT_H2N_U32(pImage->ExpStatSN);
     memcpy(paReqBHS + 8, pScsiReq->pvCmd, pScsiReq->cbCmd);
+
+    pIScsiPDU->CmdSN = pImage->CmdSN;
     pImage->CmdSN++;
 
@@ -3035 +3049 @@
 {
     return (s1 < s2 && s2 - s1 < 0x80000000) || (s1 > s2 && s1 - s2 > 0x80000000);
+}
+
+static bool serial_number_greater(uint32_t s1, uint32_t s2)
+{
+    return (s1 < s2 && s2 - s1 > 0x80000000) || (s1 > s2 && s1 - s2 < 0x80000000);
 }