From e2683957fb268c6b29316fd9e7191e13239a30a5 Mon Sep 17 00:00:00 2001 From: Daniel De Graaf Date: Tue, 30 Jul 2013 13:29:47 -0400 Subject: drivers/tpm: add xen tpmfront interface This is a complete rewrite of the Xen TPM frontend driver, taking advantage of a simplified frontend/backend interface and adding support for cancellation and timeouts. The backend for this driver is provided by a vTPM stub domain using the interface in Xen 4.3. Signed-off-by: Daniel De Graaf Acked-by: Matthew Fioravante Reviewed-by: Konrad Rzeszutek Wilk Acked-by: Peter Huewe Reviewed-by: Peter Huewe Signed-off-by: Konrad Rzeszutek Wilk --- include/xen/interface/io/tpmif.h | 52 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 include/xen/interface/io/tpmif.h (limited to 'include/xen/interface/io') diff --git a/include/xen/interface/io/tpmif.h b/include/xen/interface/io/tpmif.h new file mode 100644 index 000000000000..28e7dcd75e82 --- /dev/null +++ b/include/xen/interface/io/tpmif.h @@ -0,0 +1,52 @@ +/****************************************************************************** + * tpmif.h + * + * TPM I/O interface for Xen guest OSes, v2 + * + * This file is in the public domain. + * + */ + +#ifndef __XEN_PUBLIC_IO_TPMIF_H__ +#define __XEN_PUBLIC_IO_TPMIF_H__ + +/* + * Xenbus state machine + * + * Device open: + * 1. Both ends start in XenbusStateInitialising + * 2. Backend transitions to InitWait (frontend does not wait on this step) + * 3. Frontend populates ring-ref, event-channel, feature-protocol-v2 + * 4. Frontend transitions to Initialised + * 5. Backend maps grant and event channel, verifies feature-protocol-v2 + * 6. Backend transitions to Connected + * 7. Frontend verifies feature-protocol-v2, transitions to Connected + * + * Device close: + * 1. State is changed to XenbusStateClosing + * 2. Frontend transitions to Closed + * 3. Backend unmaps grant and event, changes state to InitWait + */ + +enum vtpm_shared_page_state { + VTPM_STATE_IDLE, /* no contents / vTPM idle / cancel complete */ + VTPM_STATE_SUBMIT, /* request ready / vTPM working */ + VTPM_STATE_FINISH, /* response ready / vTPM idle */ + VTPM_STATE_CANCEL, /* cancel requested / vTPM working */ +}; +/* The backend should only change state to IDLE or FINISH, while the + * frontend should only change to SUBMIT or CANCEL. */ + + +struct vtpm_shared_page { + uint32_t length; /* request/response length in bytes */ + + uint8_t state; /* enum vtpm_shared_page_state */ + uint8_t locality; /* for the current request */ + uint8_t pad; + + uint8_t nr_extra_pages; /* extra pages for long packets; may be zero */ + uint32_t extra_pages[0]; /* grant IDs; length in nr_extra_pages */ +}; + +#endif -- cgit v1.2.3