[PATCH 0/6] MR5926: ntdll: Always fill the 32-bit IOSB when performing I/O on overlapped handles.

[Elizabeth Figura (＠zfigura)]

Previously it was assumed that synchronous I/O fills the 64-bit IOSB, and
asynchronous I/O fills the 32-bit IOSB.

As the ntdll:wow64 tests show, this is incorrect. I/O on an overlapped handle,
whether it is synchronous or not, fills the 32-bit IOSB, and I/O on a
non-overlapped handle always fills the 64-bit IOSB.

The first half is important, since completion can be signaled before we even
return from the initial I/O call [NtReadFile() etc.] Filling the IOSB after
signaling completion is the cause of bug 56389. This patch series fixes that.

The second discrepancy does not cause any bugs, as far as I can see, and is
a bit harder to fix anyway. It is therefore not addressed by this patch series.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=56389