[reactos] 01/01: [FREELDR] Change GEOMETRY "Sectors" to "SectorsPerTrack" and introduce a new "Sectors" field (#7379)

[Hermès Bélusca-Maïto]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=3a7fe56a5d5033bcb5e87…

commit 3a7fe56a5d5033bcb5e8733fe49e7f24b9a2def3
Author:     Hermès Bélusca-Maïto <hermes.belusca-maito(a)reactos.org>
AuthorDate: Sun Sep 22 18:41:44 2024 +0200
Commit:     Hermès Bélusca-Maïto <hermes.belusca-maito(a)reactos.org>
CommitDate: Mon Sep 30 12:11:15 2024 +0200

    [FREELDR] Change GEOMETRY "Sectors" to "SectorsPerTrack" and
introduce a new "Sectors" field (#7379)
    
    ----
    Thanks to the following testers!
    - Dmitry Borisov (@disean) for testing on NEC PC-98 emulator;
    - Justin Miller (@DarkFire01) for testing on UEFI platform;
    - Stanislav Motylkov (@binarymaster) for testing on Xbox emulator
      (xemu), both livecd and bootcd.
    ----
    
    "SectorsPerTrack" is for the legacy Cylinders/Heads/Sectors(PerTrack)
    scheme.
    
    - On BIOS-based PCs, INT 13h can return (for LBA-only drives) an invalid
      geometry, like: C/H/S = (-1)/(-1)/(-1). This is also what happens in
      our hwide.c driver (see IdentifyDevice() for ATAPI devices):
   
https://github.com/reactos/reactos/blob/db419efbf26c78e39fb57bcaf4f9e4d915d…
    
      as well as on VirtualBox for CD-ROMs:
    https://www.virtualbox.org/browser/vbox/trunk/src/VBox/Devices/PC/BIOS/disk…
    
    - Therefore, we cannot reliably calculate a valid total number of sectors
      by multiplying the Cylinders*Heads*SectorsPerTrack values. In addition,
      such a multiplication could overflow a 32-bit ULONG.
      Thus, a separate ULONGLONG Sectors member is required to hold such a
      value, that is retrieved differently. For example for ATAPI devices,
      our hwide.c driver does return a valid TotalSectors value, even though
      CHS values are invalid. Other platforms, like UEFI, just work using
      logical block addressing (LBA) values (see EFI_BLOCK_IO_MEDIA).
    
    - uefidisk.c : Per the spec, EFI_BLOCK_IO_MEDIA::LastBlock contains
      "The last LBA on the device. [...] For ATA devices, this is reported
      in IDENTIFY DEVICE data words 60-61 (i.e., Total number of user
      addressable logical sectors) _minus one_.
      For SCSI devices, this is reported in the READ CAPACITY parameter
      data 'Returned Logical Block Address field' _minus one_."
      In other words, LastBlock is a zero-based LBA index quantity. The
      corresponding total number of valid "sectors"/blocks of the device
      is therefore, (LastBlock + 1).
    
    - Cleanup some old disabled code.
---
 boot/freeldr/freeldr/arch/i386/hwdisk.c        |  2 +-
 boot/freeldr/freeldr/arch/i386/pc/machpc.c     | 22 ++------
 boot/freeldr/freeldr/arch/i386/pc/pcdisk.c     | 40 +++++++--------
 boot/freeldr/freeldr/arch/i386/pc/pchw.c       |  4 +-
 boot/freeldr/freeldr/arch/i386/pc98/pc98disk.c | 70 +++++++++++++++-----------
 boot/freeldr/freeldr/arch/i386/pc98/pc98hw.c   |  6 +--
 boot/freeldr/freeldr/arch/i386/xbox/machxbox.c | 13 ++---
 boot/freeldr/freeldr/arch/i386/xbox/xboxdisk.c |  3 +-
 boot/freeldr/freeldr/arch/uefi/uefidisk.c      | 13 ++---
 boot/freeldr/freeldr/include/arch/pc/machpc.h  |  1 -
 boot/freeldr/freeldr/include/disk.h            | 21 ++++----
 11 files changed, 92 insertions(+), 103 deletions(-)

diff --git a/boot/freeldr/freeldr/arch/i386/hwdisk.c
b/boot/freeldr/freeldr/arch/i386/hwdisk.c
index 421fd38d48c..c804137491e 100644
--- a/boot/freeldr/freeldr/arch/i386/hwdisk.c
+++ b/boot/freeldr/freeldr/arch/i386/hwdisk.c
@@ -137,7 +137,7 @@ DiskOpen(CHAR* Path, OPENMODE OpenMode, ULONG* FileId)
         }
 
         SectorOffset = 0;
-        SectorCount = (ULONGLONG)Geometry.Cylinders * Geometry.Heads *
Geometry.Sectors;
+        SectorCount = Geometry.Sectors;
     }
 
     Context = FrLdrTempAlloc(sizeof(DISKCONTEXT), TAG_HW_DISK_CONTEXT);
diff --git a/boot/freeldr/freeldr/arch/i386/pc/machpc.c
b/boot/freeldr/freeldr/arch/i386/pc/machpc.c
index 639895ec25b..fff1673feb4 100644
--- a/boot/freeldr/freeldr/arch/i386/pc/machpc.c
+++ b/boot/freeldr/freeldr/arch/i386/pc/machpc.c
@@ -121,13 +121,10 @@ PcGetHarddiskConfigurationData(UCHAR DriveNumber, ULONG* pSize)
 {
     PCM_PARTIAL_RESOURCE_LIST PartialResourceList;
     PCM_DISK_GEOMETRY_DEVICE_DATA DiskGeometry;
-    // EXTENDED_GEOMETRY ExtGeometry;
     GEOMETRY Geometry;
     ULONG Size;
 
-    //
-    // Initialize returned size
-    //
+    /* Initialize returned size */
     *pSize = 0;
 
     /* Set 'Configuration Data' value */
@@ -155,22 +152,11 @@ PcGetHarddiskConfigurationData(UCHAR DriveNumber, ULONG* pSize)
     DiskGeometry = (PVOID)(((ULONG_PTR)PartialResourceList) +
sizeof(CM_PARTIAL_RESOURCE_LIST));
 
     /* Get the disk geometry */
-#if 0 // This is somehow replaced by what PcDiskGetDriveGeometry() does internally.
-    ExtGeometry.Size = sizeof(EXTENDED_GEOMETRY);
-    if (DiskGetExtendedDriveParameters(DriveNumber, &ExtGeometry,
ExtGeometry.Size))
-    {
-        DiskGeometry->BytesPerSector = ExtGeometry.BytesPerSector;
-        DiskGeometry->NumberOfCylinders = ExtGeometry.Cylinders;
-        DiskGeometry->SectorsPerTrack = ExtGeometry.SectorsPerTrack;
-        DiskGeometry->NumberOfHeads = ExtGeometry.Heads;
-    }
-    else
-#endif
     if (PcDiskGetDriveGeometry(DriveNumber, &Geometry))
     {
         DiskGeometry->BytesPerSector = Geometry.BytesPerSector;
         DiskGeometry->NumberOfCylinders = Geometry.Cylinders;
-        DiskGeometry->SectorsPerTrack = Geometry.Sectors;
+        DiskGeometry->SectorsPerTrack = Geometry.SectorsPerTrack;
         DiskGeometry->NumberOfHeads = Geometry.Heads;
     }
     else
@@ -186,9 +172,7 @@ PcGetHarddiskConfigurationData(UCHAR DriveNumber, ULONG* pSize)
           DiskGeometry->SectorsPerTrack,
           DiskGeometry->BytesPerSector);
 
-    //
-    // Return configuration data
-    //
+    /* Return configuration data */
     *pSize = Size;
     return PartialResourceList;
 }
diff --git a/boot/freeldr/freeldr/arch/i386/pc/pcdisk.c
b/boot/freeldr/freeldr/arch/i386/pc/pcdisk.c
index 28e7fd66a76..1bd498e6730 100644
--- a/boot/freeldr/freeldr/arch/i386/pc/pcdisk.c
+++ b/boot/freeldr/freeldr/arch/i386/pc/pcdisk.c
@@ -443,8 +443,12 @@ InitDriveGeometry(
     Cylinders++;
     DiskDrive->Geometry.Cylinders = Cylinders;
     DiskDrive->Geometry.Heads = RegsOut.b.dh + 1;
-    DiskDrive->Geometry.Sectors = RegsOut.b.cl & 0x3F;
-    DiskDrive->Geometry.BytesPerSector = 512;     /* Just assume 512 bytes per sector
*/
+    DiskDrive->Geometry.SectorsPerTrack = RegsOut.b.cl & 0x3F;
+    DiskDrive->Geometry.BytesPerSector = 512;   /* Just assume 512 bytes per sector
*/
+
+    DiskDrive->Geometry.Sectors = (ULONGLONG)DiskDrive->Geometry.Cylinders *
+                                             DiskDrive->Geometry.Heads *
+                                             DiskDrive->Geometry.SectorsPerTrack;
 
     TRACE("Regular Int13h(0x%x) returned:\n"
           "Cylinders  : 0x%x\n"
@@ -454,7 +458,7 @@ InitDriveGeometry(
           DriveNumber,
           DiskDrive->Geometry.Cylinders,
           DiskDrive->Geometry.Heads,
-          DiskDrive->Geometry.Sectors, RegsOut.b.cl,
+          DiskDrive->Geometry.SectorsPerTrack, RegsOut.b.cl,
           DiskDrive->Geometry.BytesPerSector);
 
     return Success;
@@ -645,40 +649,35 @@ PcDiskReadLogicalSectorsCHS(
     ULONG RetryCount;
 
     DriveGeometry = DiskDrive->Geometry;
-    if (DriveGeometry.Sectors == 0 || DriveGeometry.Heads == 0)
+    if (DriveGeometry.SectorsPerTrack == 0 || DriveGeometry.Heads == 0)
         return FALSE;
 
     while (SectorCount > 0)
     {
         /*
          * Calculate the physical disk offsets.
-         * Note: DriveGeometry.Sectors < 64
+         * Note: DriveGeometry.SectorsPerTrack < 64
          */
-        PhysicalSector = 1 + (UCHAR)(SectorNumber % DriveGeometry.Sectors);
-        PhysicalHead = (UCHAR)((SectorNumber / DriveGeometry.Sectors) %
DriveGeometry.Heads);
-        PhysicalTrack = (ULONG)((SectorNumber / DriveGeometry.Sectors) /
DriveGeometry.Heads);
+        PhysicalSector = 1 + (UCHAR)(SectorNumber % DriveGeometry.SectorsPerTrack);
+        PhysicalHead = (UCHAR)((SectorNumber / DriveGeometry.SectorsPerTrack) %
DriveGeometry.Heads);
+        PhysicalTrack = (ULONG)((SectorNumber / DriveGeometry.SectorsPerTrack) /
DriveGeometry.Heads);
 
         /* Calculate how many sectors we need to read this round */
         if (PhysicalSector > 1)
         {
-            if (SectorCount >= (DriveGeometry.Sectors - (PhysicalSector - 1)))
-                NumberOfSectorsToRead = (DriveGeometry.Sectors - (PhysicalSector - 1));
-            else
-                NumberOfSectorsToRead = SectorCount;
+            NumberOfSectorsToRead = min(SectorCount,
+                                        (DriveGeometry.SectorsPerTrack - (PhysicalSector
- 1)));
         }
         else
         {
-            if (SectorCount >= DriveGeometry.Sectors)
-                NumberOfSectorsToRead = DriveGeometry.Sectors;
-            else
-                NumberOfSectorsToRead = SectorCount;
+            NumberOfSectorsToRead = min(SectorCount, DriveGeometry.SectorsPerTrack);
         }
 
         /* Make sure the read is within the geometry boundaries */
         if ((PhysicalHead >= DriveGeometry.Heads) ||
             (PhysicalTrack >= DriveGeometry.Cylinders) ||
-            ((NumberOfSectorsToRead + PhysicalSector) > (DriveGeometry.Sectors + 1))
||
-            (PhysicalSector > DriveGeometry.Sectors))
+            ((NumberOfSectorsToRead + PhysicalSector) > (DriveGeometry.SectorsPerTrack
+ 1)) ||
+            (PhysicalSector > DriveGeometry.SectorsPerTrack))
         {
             DiskError("Disk read exceeds drive geometry limits.", 0);
             return FALSE;
@@ -817,8 +816,9 @@ PcDiskGetDriveGeometry(UCHAR DriveNumber, PGEOMETRY Geometry)
         /* Extended geometry has been initialized, return it */
         Geometry->Cylinders = DiskDrive->ExtGeometry.Cylinders;
         Geometry->Heads = DiskDrive->ExtGeometry.Heads;
-        Geometry->Sectors = DiskDrive->ExtGeometry.SectorsPerTrack;
+        Geometry->SectorsPerTrack = DiskDrive->ExtGeometry.SectorsPerTrack;
         Geometry->BytesPerSector = DiskDrive->ExtGeometry.BytesPerSector;
+        Geometry->Sectors = DiskDrive->ExtGeometry.Sectors;
     }
     else
     /* Fall back to legacy BIOS geometry */
@@ -845,7 +845,7 @@ PcDiskGetCacheableBlockCount(UCHAR DriveNumber)
     if (DiskDrive->Int13ExtensionsSupported)
         return 64;
     else
-        return DiskDrive->Geometry.Sectors;
+        return DiskDrive->Geometry.SectorsPerTrack;
 }
 
 /* EOF */
diff --git a/boot/freeldr/freeldr/arch/i386/pc/pchw.c
b/boot/freeldr/freeldr/arch/i386/pc/pchw.c
index 4e8249dd99f..e0e24da5108 100644
--- a/boot/freeldr/freeldr/arch/i386/pc/pchw.c
+++ b/boot/freeldr/freeldr/arch/i386/pc/pchw.c
@@ -394,7 +394,7 @@ DetectBiosDisks(PCONFIGURATION_COMPONENT_DATA SystemKey,
         {
             Int13Drives[i].DriveSelect = DriveNumber;
             Int13Drives[i].MaxCylinders = Geometry.Cylinders - 1;
-            Int13Drives[i].SectorsPerTrack = (USHORT)Geometry.Sectors;
+            Int13Drives[i].SectorsPerTrack = (USHORT)Geometry.SectorsPerTrack;
             Int13Drives[i].MaxHeads = (USHORT)Geometry.Heads - 1;
             Int13Drives[i].NumberDrives = DiskCount;
 
@@ -402,7 +402,7 @@ DetectBiosDisks(PCONFIGURATION_COMPONENT_DATA SystemKey,
                   DriveNumber,
                   Geometry.Cylinders - 1,
                   Geometry.Heads - 1,
-                  Geometry.Sectors,
+                  Geometry.SectorsPerTrack,
                   Geometry.BytesPerSector);
         }
     }
diff --git a/boot/freeldr/freeldr/arch/i386/pc98/pc98disk.c
b/boot/freeldr/freeldr/arch/i386/pc98/pc98disk.c
index 71a21e36267..9eef9d45f71 100644
--- a/boot/freeldr/freeldr/arch/i386/pc98/pc98disk.c
+++ b/boot/freeldr/freeldr/arch/i386/pc98/pc98disk.c
@@ -268,11 +268,11 @@ Pc98DiskReadLogicalSectorsCHS(
     {
         /*
          * Calculate the physical disk offsets.
-         * Note: DriveGeometry.Sectors < 64
+         * Note: DriveGeometry.SectorsPerTrack < 64
          */
-        PhysicalSector = (UCHAR)(SectorNumber % DriveGeometry.Sectors);
-        PhysicalHead = (UCHAR)((SectorNumber / DriveGeometry.Sectors) %
DriveGeometry.Heads);
-        PhysicalTrack = (ULONG)((SectorNumber / DriveGeometry.Sectors) /
DriveGeometry.Heads);
+        PhysicalSector = (UCHAR)(SectorNumber % DriveGeometry.SectorsPerTrack);
+        PhysicalHead = (UCHAR)((SectorNumber / DriveGeometry.SectorsPerTrack) %
DriveGeometry.Heads);
+        PhysicalTrack = (ULONG)((SectorNumber / DriveGeometry.SectorsPerTrack) /
DriveGeometry.Heads);
 
         /* Floppy sectors value always start at 1 */
         if (DiskDrive->Type & DRIVE_FDD)
@@ -281,24 +281,19 @@ Pc98DiskReadLogicalSectorsCHS(
         /* Calculate how many sectors we need to read this round */
         if (PhysicalSector > 1)
         {
-            if (SectorCount >= (DriveGeometry.Sectors - (PhysicalSector - 1)))
-                NumberOfSectorsToRead = (DriveGeometry.Sectors - (PhysicalSector - 1));
-            else
-                NumberOfSectorsToRead = SectorCount;
+            NumberOfSectorsToRead = min(SectorCount,
+                                        (DriveGeometry.SectorsPerTrack - (PhysicalSector
- 1)));
         }
         else
         {
-            if (SectorCount >= DriveGeometry.Sectors)
-                NumberOfSectorsToRead = DriveGeometry.Sectors;
-            else
-                NumberOfSectorsToRead = SectorCount;
+            NumberOfSectorsToRead = min(SectorCount, DriveGeometry.SectorsPerTrack);
         }
 
         /* Make sure the read is within the geometry boundaries */
         if ((PhysicalHead >= DriveGeometry.Heads) ||
             (PhysicalTrack >= DriveGeometry.Cylinders) ||
-            ((NumberOfSectorsToRead + PhysicalSector) > (DriveGeometry.Sectors + 1))
||
-            (PhysicalSector > DriveGeometry.Sectors))
+            ((NumberOfSectorsToRead + PhysicalSector) > (DriveGeometry.SectorsPerTrack
+ 1)) ||
+            (PhysicalSector > DriveGeometry.SectorsPerTrack))
         {
             DiskError("Disk read exceeds drive geometry limits.", 0);
             return FALSE;
@@ -439,7 +434,7 @@ InitScsiDrive(
 
         DiskDrive->Geometry.Cylinders = RegsOut.w.cx;
         DiskDrive->Geometry.Heads = RegsOut.b.dh;
-        DiskDrive->Geometry.Sectors = RegsOut.b.dl;
+        DiskDrive->Geometry.SectorsPerTrack = RegsOut.b.dl;
         DiskDrive->Geometry.BytesPerSector = RegsOut.w.bx;
         DiskDrive->LBASupported = FALSE;
         DiskDrive->IsRemovable = FALSE;
@@ -454,7 +449,7 @@ InitScsiDrive(
                 /* CD-ROM */
                 DiskDrive->Geometry.Cylinders = 0xFFFF;
                 DiskDrive->Geometry.Heads = 0xFFFF;
-                DiskDrive->Geometry.Sectors = 0xFFFF;
+                DiskDrive->Geometry.SectorsPerTrack = 0xFFFF;
                 DiskDrive->Geometry.BytesPerSector = 2048;
                 DiskDrive->Type = DRIVE_CDROM;
                 DiskDrive->LBASupported = TRUE;
@@ -465,7 +460,7 @@ InitScsiDrive(
                 /* Magneto-optical drive */
                 DiskDrive->Geometry.Cylinders = 0xFFFF;
                 DiskDrive->Geometry.Heads = 8;
-                DiskDrive->Geometry.Sectors = 32;
+                DiskDrive->Geometry.SectorsPerTrack = 32;
                 DiskDrive->Geometry.BytesPerSector = 512;
                 DiskDrive->Type = DRIVE_MO;
                 DiskDrive->LBASupported = TRUE;
@@ -483,6 +478,10 @@ InitScsiDrive(
         return FALSE;
     }
 
+    DiskDrive->Geometry.Sectors = (ULONGLONG)DiskDrive->Geometry.Cylinders *
+                                             DiskDrive->Geometry.Heads *
+                                             DiskDrive->Geometry.SectorsPerTrack;
+
     DiskDrive->DaUa = DaUa;
     DiskDrive->Type |= DRIVE_SCSI;
     DiskDrive->Initialized = TRUE;
@@ -495,7 +494,7 @@ InitScsiDrive(
           DaUa,
           DiskDrive->Geometry.Cylinders,
           DiskDrive->Geometry.Heads,
-          DiskDrive->Geometry.Sectors,
+          DiskDrive->Geometry.SectorsPerTrack,
           DiskDrive->Geometry.BytesPerSector);
 
     return TRUE;
@@ -513,8 +512,10 @@ InitIdeDrive(
     {
         DiskDrive->Geometry.Cylinders = DeviceUnit->Cylinders;
         DiskDrive->Geometry.Heads = DeviceUnit->Heads;
-        DiskDrive->Geometry.Sectors = DeviceUnit->Sectors;
+        DiskDrive->Geometry.SectorsPerTrack = DeviceUnit->Sectors;
         DiskDrive->Geometry.BytesPerSector = DeviceUnit->SectorSize;
+        DiskDrive->Geometry.Sectors = DeviceUnit->TotalSectors;
+
         DiskDrive->DaUa = 0xFF;
         DiskDrive->IdeUnitNumber = UnitNumber;
         DiskDrive->Type = DRIVE_IDE | DRIVE_CDROM;
@@ -530,7 +531,7 @@ InitIdeDrive(
               UnitNumber,
               DiskDrive->Geometry.Cylinders,
               DiskDrive->Geometry.Heads,
-              DiskDrive->Geometry.Sectors,
+              DiskDrive->Geometry.SectorsPerTrack,
               DiskDrive->Geometry.BytesPerSector);
 
         return TRUE;
@@ -582,8 +583,13 @@ InitHardDrive(
 
     DiskDrive->Geometry.Cylinders = RegsOut.w.cx;
     DiskDrive->Geometry.Heads = RegsOut.b.dh;
-    DiskDrive->Geometry.Sectors = RegsOut.b.dl;
+    DiskDrive->Geometry.SectorsPerTrack = RegsOut.b.dl;
     DiskDrive->Geometry.BytesPerSector = RegsOut.w.bx;
+
+    DiskDrive->Geometry.Sectors = (ULONGLONG)DiskDrive->Geometry.Cylinders *
+                                             DiskDrive->Geometry.Heads *
+                                             DiskDrive->Geometry.SectorsPerTrack;
+
     DiskDrive->DaUa = DaUa;
     DiskDrive->Type = DRIVE_IDE;
     DiskDrive->LBASupported = FALSE;
@@ -598,7 +604,7 @@ InitHardDrive(
           DaUa,
           DiskDrive->Geometry.Cylinders,
           DiskDrive->Geometry.Heads,
-          DiskDrive->Geometry.Sectors,
+          DiskDrive->Geometry.SectorsPerTrack,
           DiskDrive->Geometry.BytesPerSector);
 
     return TRUE;
@@ -647,14 +653,14 @@ InitFloppyDrive(
                 /* 320 kB 2DD */
                 DiskDrive->Geometry.Cylinders = 80;
                 DiskDrive->Geometry.Heads = 2;
-                DiskDrive->Geometry.Sectors = 16;
+                DiskDrive->Geometry.SectorsPerTrack = 16;
             }
             else
             {
                 /* 1 MB 2HD */
                 DiskDrive->Geometry.Cylinders = 77;
                 DiskDrive->Geometry.Heads = 2;
-                DiskDrive->Geometry.Sectors = 26;
+                DiskDrive->Geometry.SectorsPerTrack = 26;
             }
             break;
 
@@ -664,21 +670,21 @@ InitFloppyDrive(
                 /* 1.44 MB 2HD */
                 DiskDrive->Geometry.Cylinders = 80;
                 DiskDrive->Geometry.Heads = 2;
-                DiskDrive->Geometry.Sectors = 18;
+                DiskDrive->Geometry.SectorsPerTrack = 18;
             }
             else if (DeviceAddress == 0x70 || DeviceAddress == 0xF0)
             {
                 /* 720/640 kB 2DD */
                 DiskDrive->Geometry.Cylinders = 80;
                 DiskDrive->Geometry.Heads = 2;
-                DiskDrive->Geometry.Sectors = 8;
+                DiskDrive->Geometry.SectorsPerTrack = 8;
             }
             else
             {
                 /* 1.2 MB 2HC */
                 DiskDrive->Geometry.Cylinders = 80;
                 DiskDrive->Geometry.Heads = 2;
-                DiskDrive->Geometry.Sectors = 15;
+                DiskDrive->Geometry.SectorsPerTrack = 15;
             }
             break;
 
@@ -686,7 +692,7 @@ InitFloppyDrive(
             /* 1.25 MB 2HD */
             DiskDrive->Geometry.Cylinders = 77;
             DiskDrive->Geometry.Heads = 2;
-            DiskDrive->Geometry.Sectors = 8;
+            DiskDrive->Geometry.SectorsPerTrack = 8;
             break;
 
         default:
@@ -695,6 +701,10 @@ InitFloppyDrive(
     }
 
     DiskDrive->Geometry.BytesPerSector = BytesPerSector;
+    DiskDrive->Geometry.Sectors = (ULONGLONG)DiskDrive->Geometry.Cylinders *
+                                             DiskDrive->Geometry.Heads *
+                                             DiskDrive->Geometry.SectorsPerTrack;
+
     DiskDrive->DaUa = DaUa;
     DiskDrive->Type = DRIVE_FDD;
     DiskDrive->LBASupported = FALSE;
@@ -709,7 +719,7 @@ InitFloppyDrive(
           DaUa,
           DiskDrive->Geometry.Cylinders,
           DiskDrive->Geometry.Heads,
-          DiskDrive->Geometry.Sectors,
+          DiskDrive->Geometry.SectorsPerTrack,
           DiskDrive->Geometry.BytesPerSector);
 
     return TRUE;
@@ -898,5 +908,5 @@ Pc98DiskGetCacheableBlockCount(UCHAR DriveNumber)
     if (DiskDrive->LBASupported)
         return 64;
     else
-        return DiskDrive->Geometry.Sectors;
+        return DiskDrive->Geometry.SectorsPerTrack;
 }
diff --git a/boot/freeldr/freeldr/arch/i386/pc98/pc98hw.c
b/boot/freeldr/freeldr/arch/i386/pc98/pc98hw.c
index 98264eec03c..6cff3e86400 100644
--- a/boot/freeldr/freeldr/arch/i386/pc98/pc98hw.c
+++ b/boot/freeldr/freeldr/arch/i386/pc98/pc98hw.c
@@ -349,7 +349,7 @@ Pc98GetHarddiskConfigurationData(UCHAR DriveNumber, ULONG* pSize)
     {
         DiskGeometry->BytesPerSector = Geometry.BytesPerSector;
         DiskGeometry->NumberOfCylinders = Geometry.Cylinders;
-        DiskGeometry->SectorsPerTrack = Geometry.Sectors;
+        DiskGeometry->SectorsPerTrack = Geometry.SectorsPerTrack;
         DiskGeometry->NumberOfHeads = Geometry.Heads;
     }
     else
@@ -423,7 +423,7 @@ DetectBiosDisks(
         {
             Int13Drives[i].DriveSelect = DriveNumber;
             Int13Drives[i].MaxCylinders = Geometry.Cylinders - 1;
-            Int13Drives[i].SectorsPerTrack = (USHORT)Geometry.Sectors;
+            Int13Drives[i].SectorsPerTrack = (USHORT)Geometry.SectorsPerTrack;
             Int13Drives[i].MaxHeads = (USHORT)Geometry.Heads - 1;
             Int13Drives[i].NumberDrives = DiskCount;
 
@@ -431,7 +431,7 @@ DetectBiosDisks(
                   DriveNumber,
                   Geometry.Cylinders - 1,
                   Geometry.Heads - 1,
-                  Geometry.Sectors,
+                  Geometry.SectorsPerTrack,
                   Geometry.BytesPerSector);
         }
     }
diff --git a/boot/freeldr/freeldr/arch/i386/xbox/machxbox.c
b/boot/freeldr/freeldr/arch/i386/xbox/machxbox.c
index 97b38062d84..6c0b094f49b 100644
--- a/boot/freeldr/freeldr/arch/i386/xbox/machxbox.c
+++ b/boot/freeldr/freeldr/arch/i386/xbox/machxbox.c
@@ -95,13 +95,10 @@ XboxGetHarddiskConfigurationData(UCHAR DriveNumber, ULONG* pSize)
 {
     PCM_PARTIAL_RESOURCE_LIST PartialResourceList;
     PCM_DISK_GEOMETRY_DEVICE_DATA DiskGeometry;
-    //EXTENDED_GEOMETRY ExtGeometry;
     GEOMETRY Geometry;
     ULONG Size;
 
-    //
-    // Initialize returned size
-    //
+    /* Initialize returned size */
     *pSize = 0;
 
     /* Set 'Configuration Data' value */
@@ -129,13 +126,11 @@ XboxGetHarddiskConfigurationData(UCHAR DriveNumber, ULONG* pSize)
     DiskGeometry = (PVOID)(((ULONG_PTR)PartialResourceList) +
sizeof(CM_PARTIAL_RESOURCE_LIST));
 
     /* Get the disk geometry */
-    //ExtGeometry.Size = sizeof(EXTENDED_GEOMETRY);
-
     if (XboxDiskGetDriveGeometry(DriveNumber, &Geometry))
     {
         DiskGeometry->BytesPerSector = Geometry.BytesPerSector;
         DiskGeometry->NumberOfCylinders = Geometry.Cylinders;
-        DiskGeometry->SectorsPerTrack = Geometry.Sectors;
+        DiskGeometry->SectorsPerTrack = Geometry.SectorsPerTrack;
         DiskGeometry->NumberOfHeads = Geometry.Heads;
     }
     else
@@ -151,9 +146,7 @@ XboxGetHarddiskConfigurationData(UCHAR DriveNumber, ULONG* pSize)
           DiskGeometry->SectorsPerTrack,
           DiskGeometry->BytesPerSector);
 
-    //
-    // Return configuration data
-    //
+    /* Return configuration data */
     *pSize = Size;
     return PartialResourceList;
 }
diff --git a/boot/freeldr/freeldr/arch/i386/xbox/xboxdisk.c
b/boot/freeldr/freeldr/arch/i386/xbox/xboxdisk.c
index 06e7e2d6691..4afdc99c398 100644
--- a/boot/freeldr/freeldr/arch/i386/xbox/xboxdisk.c
+++ b/boot/freeldr/freeldr/arch/i386/xbox/xboxdisk.c
@@ -112,8 +112,9 @@ XboxDiskGetDriveGeometry(UCHAR DriveNumber, PGEOMETRY Geometry)
 
     Geometry->Cylinders = DeviceUnit->Cylinders;
     Geometry->Heads = DeviceUnit->Heads;
-    Geometry->Sectors = DeviceUnit->Sectors;
+    Geometry->SectorsPerTrack = DeviceUnit->Sectors;
     Geometry->BytesPerSector = DeviceUnit->SectorSize;
+    Geometry->Sectors = DeviceUnit->TotalSectors;
 
     return TRUE;
 }
diff --git a/boot/freeldr/freeldr/arch/uefi/uefidisk.c
b/boot/freeldr/freeldr/arch/uefi/uefidisk.c
index 98d19b346f1..c7e89e92cea 100644
--- a/boot/freeldr/freeldr/arch/uefi/uefidisk.c
+++ b/boot/freeldr/freeldr/arch/uefi/uefidisk.c
@@ -185,7 +185,7 @@ UefiDiskOpen(CHAR *Path, OPENMODE OpenMode, ULONG *FileId)
         }
 
         SectorOffset = 0;
-        SectorCount = (ULONGLONG)Geometry.Cylinders * Geometry.Heads *
Geometry.Sectors;
+        SectorCount = Geometry.Sectors;
     }
 
     Context = FrLdrTempAlloc(sizeof(DISKCONTEXT), TAG_HW_DISK_CONTEXT);
@@ -577,10 +577,11 @@ UefiDiskGetDriveGeometry(UCHAR DriveNumber, PGEOMETRY Geometry)
 
     UefiDriveNumber = InternalUefiDisk[DriveNumber - FIRST_BIOS_DISK].UefiRootNumber;
     GlobalSystemTable->BootServices->HandleProtocol(handles[UefiDriveNumber],
&bioGuid, (void**)&bio);
-    Geometry->Cylinders = 1;      // Not relevant for the UEFI BIO protocol
-    Geometry->Heads = 1;          // Not relevant for the UEFI BIO protocol
-    Geometry->Sectors = bio->Media->LastBlock;        // Number of sectors per
track
-    Geometry->BytesPerSector = bio->Media->BlockSize; // Number of bytes per
sector
+    Geometry->Cylinders = 1; // Not relevant for the UEFI BIO protocol
+    Geometry->Heads = 1;     // Not relevant for the UEFI BIO protocol
+    Geometry->SectorsPerTrack = (bio->Media->LastBlock + 1);
+    Geometry->BytesPerSector = bio->Media->BlockSize;
+    Geometry->Sectors = (bio->Media->LastBlock + 1);
 
     return TRUE;
 }
@@ -592,5 +593,5 @@ UefiDiskGetCacheableBlockCount(UCHAR DriveNumber)
     TRACE("UefiDiskGetCacheableBlockCount: DriveNumber: %d\n",
UefiDriveNumber);
 
     GlobalSystemTable->BootServices->HandleProtocol(handles[UefiDriveNumber],
&bioGuid, (void**)&bio);
-    return bio->Media->LastBlock;
+    return (bio->Media->LastBlock + 1);
 }
diff --git a/boot/freeldr/freeldr/include/arch/pc/machpc.h
b/boot/freeldr/freeldr/include/arch/pc/machpc.h
index 2263d75778c..0f68027eef3 100644
--- a/boot/freeldr/freeldr/include/arch/pc/machpc.h
+++ b/boot/freeldr/freeldr/include/arch/pc/machpc.h
@@ -58,7 +58,6 @@ extern ULONG FrldrBootPartition;
 
 LONG DiskReportError(BOOLEAN bShowError);
 BOOLEAN DiskResetController(UCHAR DriveNumber);
-// BOOLEAN DiskGetExtendedDriveParameters(UCHAR DriveNumber, PVOID Buffer, USHORT
BufferSize);
 
 BOOLEAN PcDiskReadLogicalSectors(UCHAR DriveNumber, ULONGLONG SectorNumber, ULONG
SectorCount, PVOID Buffer);
 BOOLEAN PcDiskGetDriveGeometry(UCHAR DriveNumber, PGEOMETRY DriveGeometry);
diff --git a/boot/freeldr/freeldr/include/disk.h b/boot/freeldr/freeldr/include/disk.h
index b08993a5e8f..ec12a8f4b31 100644
--- a/boot/freeldr/freeldr/include/disk.h
+++ b/boot/freeldr/freeldr/include/disk.h
@@ -21,19 +21,22 @@
 
 #include <reactos/rosioctl.h>
 
+/* FreeLoader-specific disk geometry structure */
 typedef struct _GEOMETRY
 {
-    ULONG   Cylinders;      // Number of cylinders on the disk
-    ULONG   Heads;          // Number of heads on the disk
-    ULONG   Sectors;        // Number of sectors per track
-    ULONG   BytesPerSector; // Number of bytes per sector
-
+    ULONG Cylinders;       ///< Number of cylinders on the disk
+    ULONG Heads;           ///< Number of heads on the disk
+    ULONG SectorsPerTrack; ///< Number of sectors per track
+    ULONG BytesPerSector;  ///< Number of bytes per sector
+    ULONGLONG Sectors;     ///< Total number of disk sectors/LBA blocks
 } GEOMETRY, *PGEOMETRY;
 
+#include <pshpack1.h>
+
 /*
- * Extended disk geometry (Int13 / ah=48h)
+ * Extended disk geometry (Int13 / AH=48h)
+ * See also ntdddisk.h DISK_EX_INT13_INFO
  */
-#include <pshpack1.h>
 typedef struct _EXTENDED_GEOMETRY
 {
     USHORT      Size;
@@ -44,7 +47,6 @@ typedef struct _EXTENDED_GEOMETRY
     ULONGLONG   Sectors;
     USHORT      BytesPerSector;
     ULONG       PDPTE;
-
 } EXTENDED_GEOMETRY, *PEXTENDED_GEOMETRY;
 
 /*
@@ -63,7 +65,6 @@ typedef struct _PARTITION_TABLE_ENTRY
     UCHAR   EndCylinder;                // Ending cylinder# (low order bits of cylinder
#)
     ULONG   SectorCountBeforePartition; // Number of sectors preceding the partition
     ULONG   PartitionSectorCount;       // Number of sectors in the partition
-
 } PARTITION_TABLE_ENTRY, *PPARTITION_TABLE_ENTRY;
 
 /*
@@ -76,8 +77,8 @@ typedef struct _MASTER_BOOT_RECORD
     USHORT  Reserved;                           /* 0x1BC */
     PARTITION_TABLE_ENTRY   PartitionTable[4];  /* 0x1BE */
     USHORT  MasterBootRecordMagic;              /* 0x1FE */
-
 } MASTER_BOOT_RECORD, *PMASTER_BOOT_RECORD;
+
 #include <poppack.h>
 
 /*