OvmfPkg: XenPvBlkDxe: handle empty cdrom drives

Empty cdroms are not going to connect, avoid waiting for the backend to
switch to state 4, which is never going to happen, and return
error instead from XenPvBlockFrontInitialization(). Detect an
empty cdrom by looking at the "params" node on xenstore, which is set to
"" or "aio:" for empty drives by libxl.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18651 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
Stefano Stabellini 2015-10-21 12:44:12 +00:00 committed by lersek
parent f4c3c92396
commit 0f34a05110
1 changed files with 15 additions and 0 deletions

View File

@ -169,6 +169,7 @@ XenPvBlockFrontInitialization (
XEN_BLOCK_FRONT_DEVICE *Dev;
XenbusState State;
UINT64 Value;
CHAR8 *Params;
ASSERT (NodeName != NULL);
@ -186,6 +187,20 @@ XenPvBlockFrontInitialization (
}
FreePool (DeviceType);
if (Dev->MediaInfo.CdRom) {
Status = XenBusIo->XsBackendRead (XenBusIo, XST_NIL, "params", (VOID**)&Params);
if (Status != XENSTORE_STATUS_SUCCESS) {
DEBUG ((EFI_D_ERROR, "%a: Failed to read params (%d)\n", __FUNCTION__, Status));
goto Error;
}
if (AsciiStrLen (Params) == 0 || AsciiStrCmp (Params, "aio:") == 0) {
FreePool (Params);
DEBUG ((EFI_D_INFO, "%a: Empty cdrom\n", __FUNCTION__));
goto Error;
}
FreePool (Params);
}
Status = XenBusReadUint64 (XenBusIo, "backend-id", FALSE, &Value);
if (Status != XENSTORE_STATUS_SUCCESS || Value > MAX_UINT16) {
DEBUG ((EFI_D_ERROR, "XenPvBlk: Failed to get backend-id (%d)\n",