| /****************************************************************************** | |
| * 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 |