[Qemu-devel] [PATCH v2 3/7] tpm: implement tpm_backend_wait_cmd_completed

[Stefan Berger <stefanb@linux.vnet.ibm.com>]

Implement tpm_backend_wait_cmd_completed to synchronize with the
backend (thread) for the completion of a command.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
---
 backends/tpm.c               | 10 ++++++++++
 include/sysemu/tpm_backend.h |  8 ++++++++
 2 files changed, 18 insertions(+)

diff --git a/backends/tpm.c b/backends/tpm.c
index 2f60166..6e26832 100644
--- a/backends/tpm.c
+++ b/backends/tpm.c
@@ -28,6 +28,16 @@ void tpm_backend_cmd_completed(TPMBackend *s)
     qemu_mutex_unlock(&s->state_lock);
 }
 
+void tpm_backend_wait_cmd_completed(TPMBackend *s)
+{
+    qemu_mutex_lock(&s->state_lock);
+
+    if (s->tpm_busy) {
+        qemu_cond_wait(&s->cmd_complete, &s->state_lock);
+    }
+    qemu_mutex_unlock(&s->state_lock);
+}
+
 static void tpm_backend_request_completed_bh(void *opaque)
 {
     TPMBackend *s = TPM_BACKEND(opaque);
diff --git a/include/sysemu/tpm_backend.h b/include/sysemu/tpm_backend.h
index e08c51d..8c271f4 100644
--- a/include/sysemu/tpm_backend.h
+++ b/include/sysemu/tpm_backend.h
@@ -207,6 +207,14 @@ TPMInfo *tpm_backend_query_tpm(TPMBackend *s);
  */
 void tpm_backend_cmd_completed(TPMBackend *s);
 
+/**
+ * tpm_backend_wait_cmd_completed:
+ * @s: the backend
+ *
+ * Wait the backend to not be busy anymore
+ */
+void tpm_backend_wait_cmd_completed(TPMBackend *s);
+
 TPMBackend *qemu_find_tpm_be(const char *id);
 
 void tpm_register_model(enum TpmModel model);
-- 
2.5.5