OvmfPkg/VirtioFsDxe: map "errno" values to EFI_STATUS

OvmfPkg/VirtioFsDxe: map "errno" values to EFI_STATUS

The VirtioFsFuseCheckResponse() function dedicates the EFI_DEVICE_ERROR
status code to the case when the Virtio Filesystem device explicitly
returns an error via the "VIRTIO_FS_FUSE_RESPONSE.Error" field.

Said field effectively carries a Linux "errno" value. Introduce a helper
function for mapping "errno" values to (hopefully) reasonable EFI_STATUS
codes. This way we'll be able to propagate "errno" values as EFI_STATUS
return codes along the UEFI call stack -- in some detail anyway.

Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3097
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20201216211125.19496-8-lersek@redhat.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@arm.com>