[Freedos-cvs] kernel/kernel initdisk.c,1.35,1.36

[Bart O. <bar...@us...>]

Update of /cvsroot/freedos/kernel/kernel
In directory sc8-pr-cvs17:/tmp/cvs-serv11163

Modified Files:
	initdisk.c 
Log Message:
Read partition tables using CHS methods unless instructed to do otherwise.
Fixes problems with some older boot sector managers like PROT.


Index: initdisk.c
===================================================================
RCS file: /cvsroot/freedos/kernel/kernel/initdisk.c,v
retrieving revision 1.35
retrieving revision 1.36
diff -u -d -r1.35 -r1.36
--- initdisk.c	6 Mar 2005 16:12:34 -0000	1.35
+++ initdisk.c	21 May 2007 01:57:21 -0000	1.36
@@ -995,7 +995,15 @@
   for (num_retries = 0; num_retries < N_RETRY; num_retries++)
   {
     regs.d.b.l = drive | 0x80;
-    if (driveParam->descflags & DF_LBA)
+    LBA_to_CHS(&chs, LBA_address, driveParam);
+    /* Some old "security" software (PROT) traps int13 and assumes non
+       LBA accesses. This statement causes partition tables to be read
+       using CHS methods even if LBA is available unless CHS can't reach
+       them. This can be overridden using kernel config parameters and
+       the extended LBA partition type indicator.
+    */
+    if ((driveParam->descflags & DF_LBA) &&
+        (InitKernelConfig.ForceLBA || ExtLBAForce || chs.Cylinder > 1023))
     {
       dap.number_of_blocks = 1;
       dap.buffer_address = buffer;
@@ -1009,7 +1017,6 @@
     }
     else
     {                           /* transfer data, using old bios functions */
-      LBA_to_CHS(&chs, LBA_address, driveParam);
       /* avoid overflow at end of track */
 
       if (chs.Cylinder > 1023)