From 4d958a1cb3f79f5e6fe643542385840b497ff867 Mon Sep 17 00:00:00 2001
From: Alexandre Julliard <julliard@winehq.org>
Date: Mon, 6 Oct 2008 17:52:23 +0200
Subject: [PATCH] ntdll: Preserve the 2K block size returned for CDROMs.

---
 dlls/ntdll/file.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/dlls/ntdll/file.c b/dlls/ntdll/file.c
index 3dee4eead17..52e75ab4795 100644
--- a/dlls/ntdll/file.c
+++ b/dlls/ntdll/file.c
@@ -2264,10 +2264,18 @@ NTSTATUS WINAPI NtQueryVolumeInformationFile( HANDLE handle, PIO_STATUS_BLOCK io
                 }
                 bsize = stfs.f_bsize;
 #endif
-                info->BytesPerSector = 512;
-                info->SectorsPerAllocationUnit = 8;
-                info->TotalAllocationUnits.QuadPart = bsize * stfs.f_blocks / (512 * 8);
-                info->AvailableAllocationUnits.QuadPart = bsize * stfs.f_bavail / (512 * 8);
+                if (bsize == 2048)  /* assume CD-ROM */
+                {
+                    info->BytesPerSector = 2048;
+                    info->SectorsPerAllocationUnit = 1;
+                }
+                else
+                {
+                    info->BytesPerSector = 512;
+                    info->SectorsPerAllocationUnit = 8;
+                }
+                info->TotalAllocationUnits.QuadPart = bsize * stfs.f_blocks / (info->BytesPerSector * info->SectorsPerAllocationUnit);
+                info->AvailableAllocationUnits.QuadPart = bsize * stfs.f_bavail / (info->BytesPerSector * info->SectorsPerAllocationUnit);
                 io->Information = sizeof(*info);
                 io->u.Status = STATUS_SUCCESS;
             }
-- 
2.11.4.GIT