Commit 00bbf50a authored by Markus Armbruster's avatar Markus Armbruster
Browse files

tpm: Clean up model registration & lookup 



We have a strict separation between enum TpmModel and tpm_models[]:

* TpmModel may have any number of members.  It just happens to have one.

* tpm_register_model() uses the first empty slot in tpm_models[].

  If you register more than tpm_models[] has space,
  tpn_register_model() fails.  Its caller silently ignores the
  failure.

  Register the same TpmModel more than once has no effect other than
  wasting tpm_models[] slots: tpm_model_is_registered() is happy with
  the first one it finds.

Since we only ever register one model, and tpm_models[] has space for
just that one, this contraption even works.

Turn tpm_models[] into a straight map from enum TpmType to bool.  Much
simpler.

Cc: Stefan Berger <stefanb@us.ibm.com>
Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-5-git-send-email-armbru@redhat.com>
Reviewed-by: default avatarMarc-André Lureau <marcandre.lureau@redhat.com>
[Commit message typo fixed]
parent a9a72aee

include/sysemu/tpm_backend.h

+1 −1
Original line number Diff line number Diff line
@@ -226,7 +226,7 @@ TPMVersion tpm_backend_get_tpm_version(TPMBackend *s); 
TPMBackend *qemu_find_tpm(const char *id);



const TPMDriverOps *tpm_get_backend_driver(const char *type);

int tpm_register_model(enum TpmModel model);

void tpm_register_model(enum TpmModel model);

void tpm_register_driver(const TPMDriverOps *tdo);



#endif

tpm.c

+5 −32
Original line number Diff line number Diff line
@@ -24,39 +24,12 @@ 
static QLIST_HEAD(, TPMBackend) tpm_backends =

    QLIST_HEAD_INITIALIZER(tpm_backends);





#define TPM_MAX_MODELS      1



static TPMDriverOps const *be_drivers[TPM_TYPE__MAX];

static bool tpm_models[TPM_MODEL__MAX];



static enum TpmModel tpm_models[TPM_MAX_MODELS] = {

    TPM_MODEL__MAX,

};



int tpm_register_model(enum TpmModel model)

{

    int i;



    for (i = 0; i < TPM_MAX_MODELS; i++) {

        if (tpm_models[i] == TPM_MODEL__MAX) {

            tpm_models[i] = model;

            return 0;

        }

    }

    error_report("Could not register TPM model");

    return 1;

}



static bool tpm_model_is_registered(enum TpmModel model)

void tpm_register_model(enum TpmModel model)

{

    int i;



    for (i = 0; i < TPM_MAX_MODELS; i++) {

        if (tpm_models[i] == model) {

            return true;

        }

    }

    return false;

    tpm_models[model] = true;

}



const TPMDriverOps *tpm_get_backend_driver(const char *type)
@@ -270,7 +243,7 @@ TPMInfoList *qmp_query_tpm(Error **errp) 
    TPMInfoList *info, *head = NULL, *cur_item = NULL;



    QLIST_FOREACH(drv, &tpm_backends, list) {

        if (!tpm_model_is_registered(drv->fe_model)) {

        if (!tpm_models[drv->fe_model]) {

            continue;

        }

        info = g_new0(TPMInfoList, 1);
@@ -317,7 +290,7 @@ TpmModelList *qmp_query_tpm_models(Error **errp) 
    TpmModelList *head = NULL, *prev = NULL, *cur_item;



    for (i = 0; i < TPM_MODEL__MAX; i++) {

        if (!tpm_model_is_registered(i)) {

        if (!tpm_models[i]) {

            continue;

        }

        cur_item = g_new0(TpmModelList, 1);