tpm-backend: Move realloc_buffer() implementation to tpm-tis model

buffer reallocation is very unlikely to be backend specific. Hence move inside
the tis.

Signed-off-by: Amarnath Valluri <amarnath.valluri@intel.com>
Reviewed-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>

4 files changed, 12 insertions, 35 deletions

diff --git a/backends/tpm.c b/backends/tpm.c
index de313c9d5a..37c84b7c66 100644
--- a/backends/tpm.c
+++ b/backends/tpm.c
@@ -80,15 +80,6 @@ bool tpm_backend_had_startup_error(TPMBackend *s)
     return s->had_startup_error;
 }
 
-size_t tpm_backend_realloc_buffer(TPMBackend *s, TPMSizedBuffer *sb)
-{
-    TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
-
-    assert(k->ops->realloc_buffer);
-
-    return k->ops->realloc_buffer(sb);
-}
-
 void tpm_backend_deliver_request(TPMBackend *s)
 {
     g_thread_pool_push(s->thread_pool, (gpointer)TPM_BACKEND_CMD_PROCESS_CMD,
diff --git a/hw/tpm/tpm_passthrough.c b/hw/tpm/tpm_passthrough.c
index 84fc49a4d3..22d3460550 100644
--- a/hw/tpm/tpm_passthrough.c
+++ b/hw/tpm/tpm_passthrough.c
@@ -247,17 +247,6 @@ static int tpm_passthrough_reset_tpm_established_flag(TPMBackend *tb,
     return 0;
 }
 
-static size_t tpm_passthrough_realloc_buffer(TPMSizedBuffer *sb)
-{
-    size_t wanted_size = 4096; /* Linux tpm.c buffer size */
-
-    if (sb->size != wanted_size) {
-        sb->buffer = g_realloc(sb->buffer, wanted_size);
-        sb->size = wanted_size;
-    }
-    return sb->size;
-}
-
 static void tpm_passthrough_cancel_cmd(TPMBackend *tb)
 {
     TPMPassthruState *tpm_pt = TPM_PASSTHROUGH(tb);
@@ -435,7 +424,6 @@ static const TPMDriverOps tpm_passthrough_driver = {
     .opts                     = tpm_passthrough_cmdline_opts,
     .desc                     = "Passthrough TPM backend driver",
     .create                   = tpm_passthrough_create,
-    .realloc_buffer           = tpm_passthrough_realloc_buffer,
     .reset                    = tpm_passthrough_reset,
     .cancel_cmd               = tpm_passthrough_cancel_cmd,
     .get_tpm_established_flag = tpm_passthrough_get_tpm_established_flag,
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
index a6440fef91..d5118e7f60 100644
--- a/hw/tpm/tpm_tis.c
+++ b/hw/tpm/tpm_tis.c
@@ -963,6 +963,16 @@ static int tpm_tis_do_startup_tpm(TPMState *s)
     return tpm_backend_startup_tpm(s->be_driver);
 }
 
+static void tpm_tis_realloc_buffer(TPMSizedBuffer *sb)
+{
+    size_t wanted_size = 4096; /* Linux tpm.c buffer size */
+
+    if (sb->size != wanted_size) {
+        sb->buffer = g_realloc(sb->buffer, wanted_size);
+        sb->size = wanted_size;
+    }
+}
+
 /*
  * Get the TPMVersion of the backend device being used
  */
@@ -1010,9 +1020,9 @@ static void tpm_tis_reset(DeviceState *dev)
         tis->loc[c].state = TPM_TIS_STATE_IDLE;
 
         tis->loc[c].w_offset = 0;
-        tpm_backend_realloc_buffer(s->be_driver, &tis->loc[c].w_buffer);
+        tpm_tis_realloc_buffer(&tis->loc[c].w_buffer);
         tis->loc[c].r_offset = 0;
-        tpm_backend_realloc_buffer(s->be_driver, &tis->loc[c].r_buffer);
+        tpm_tis_realloc_buffer(&tis->loc[c].r_buffer);
     }
 
     tpm_tis_do_startup_tpm(s);
diff --git a/include/sysemu/tpm_backend.h b/include/sysemu/tpm_backend.h
index e96c1918cc..2c798a1eb4 100644
--- a/include/sysemu/tpm_backend.h
+++ b/include/sysemu/tpm_backend.h
@@ -84,8 +84,6 @@ struct TPMDriverOps {
     /* start up the TPM on the backend */
     int (*startup_tpm)(TPMBackend *t);
 
-    size_t (*realloc_buffer)(TPMSizedBuffer *sb);
-
     void (*reset)(TPMBackend *t);
 
     void (*cancel_cmd)(TPMBackend *t);
@@ -140,16 +138,6 @@ int tpm_backend_startup_tpm(TPMBackend *s);
 bool tpm_backend_had_startup_error(TPMBackend *s);
 
 /**
- * tpm_backend_realloc_buffer:
- * @s: the backend
- * @sb: the TPMSizedBuffer to re-allocated to the size suitable for the
- *      backend.
- *
- * This function returns the size of the allocated buffer
- */
-size_t tpm_backend_realloc_buffer(TPMBackend *s, TPMSizedBuffer *sb);
-
-/**
  * tpm_backend_deliver_request:
  * @s: the backend to send the request to
  *