[Qemu-devel] [PATCH v2 2/2] tpm_spapr: Support suspend and resume

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

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
---
 hw/tpm/tpm_spapr.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 57 insertions(+), 4 deletions(-)

diff --git a/hw/tpm/tpm_spapr.c b/hw/tpm/tpm_spapr.c
index ef5e62d..0b8a424 100644
--- a/hw/tpm/tpm_spapr.c
+++ b/hw/tpm/tpm_spapr.c
@@ -248,9 +248,8 @@ static int tpm_spapr_do_crq(struct VIOsPAPRDevice *dev, uint8_t *crq_data)
     return H_SUCCESS;
 }
 
-static void tpm_spapr_request_completed(TPMIf *ti)
+static void _tpm_spapr_request_completed(SPAPRvTPMState *s)
 {
-    SPAPRvTPMState *s = VIO_SPAPR_VTPM(ti);
     TPMSpaprCRQ *crq = &s->crq;
     uint32_t len;
     int rc;
@@ -281,6 +280,13 @@ static void tpm_spapr_request_completed(TPMIf *ti)
     }
 }
 
+static void tpm_spapr_request_completed(TPMIf *ti)
+{
+    SPAPRvTPMState *s = VIO_SPAPR_VTPM(ti);
+
+    _tpm_spapr_request_completed(s);
+}
+
 static int tpm_spapr_do_startup_tpm(SPAPRvTPMState *s, size_t buffersize)
 {
     return tpm_backend_startup_tpm(s->be_driver, buffersize);
@@ -313,9 +319,56 @@ static enum TPMVersion tpm_spapr_get_version(TPMIf *ti)
     return tpm_backend_get_tpm_version(s->be_driver);
 }
 
+/* persistent state handling */
+
+static int tpm_spapr_pre_save(void *opaque)
+{
+    SPAPRvTPMState *s = opaque;
+
+    /*
+     * Synchronize with backend completion.
+     */
+    tpm_backend_wait_cmd_completed(s->be_driver);
+
+    /*
+     * we cannot deliver the results to the VM (in state
+     * SPAPR_VTPM_STATE_EXECUTION) since DMA would touch VM memory
+     */
+
+    return 0;
+}
+
+static int tpm_spapr_post_load(void *opaque,
+                               int version_id __attribute__((unused)))
+{
+    SPAPRvTPMState *s = opaque;
+
+    if (s->state == SPAPR_VTPM_STATE_EXECUTION) {
+        /*
+         * now we can deliver the results to the VM via DMA
+         */
+        _tpm_spapr_request_completed(s);
+    }
+
+    return 0;
+}
+
 static const VMStateDescription vmstate_spapr_vtpm = {
-    .name = "tpm_spapr",
-    .unmigratable = 1,
+    .name = "tpm-spapr",
+    .version_id = 1,
+    .minimum_version_id = 0,
+    .minimum_version_id_old = 0,
+    .pre_save = tpm_spapr_pre_save,
+    .post_load = tpm_spapr_post_load,
+    .fields = (VMStateField[]) {
+        VMSTATE_BUFFER(crq.raw, SPAPRvTPMState),
+        VMSTATE_UINT64(vdev.crq.qladdr, SPAPRvTPMState),
+        VMSTATE_UINT32(vdev.crq.qsize, SPAPRvTPMState),
+        VMSTATE_UINT32(vdev.crq.qnext, SPAPRvTPMState),
+        VMSTATE_UINT8(state, SPAPRvTPMState),
+        VMSTATE_BUFFER(buffer, SPAPRvTPMState),
+        VMSTATE_END_OF_LIST(),
+    }
 };
 
 static Property tpm_spapr_properties[] = {
-- 
2.5.5