Changeset 81997 in vbox

Timestamp:

Nov 19, 2019 3:57:09 PM (5 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

134797

Message:

DevATA: Changed register state at the end of read/write operations for improved compatibility with old ATA devices (see bugref:5869).

File:

• trunk/src/VBox/Devices/Storage/DevATA.cpp (modified) (1 diff)

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

@@ -1847 +1847 @@
     if (RT_SUCCESS(rc))
     {
-        ataR3SetSector(s, iLBA + cSectors);
+        /* When READ SECTORS etc. finishes, the address in the task
+         * file register points at the last sector read, not at the next
+         * sector that would be read. This ensures the registers always
+         * contain a valid sector address.
+         */
         if (s->cbElementaryTransfer == s->cbTotalTransfer)
+        {
             s->iSourceSink = ATAFN_SS_NULL;
+            ataR3SetSector(s, iLBA + cSectors - 1);
+        }
+        else
+            ataR3SetSector(s, iLBA + cSectors);
+        s->uATARegNSector -= cSectors;
         ataR3CmdOK(pCtl, s, ATA_STAT_SEEK);
     }