blob: c88c98e56508cec28f7a07d6214eba9ff505fdaf [file] [log] [blame]
From b5ffd3aa4e9bd4edb09cc84c46f78da72697a946 Mon Sep 17 00:00:00 2001
From: Stefan Berger <stefanb@linux.vnet.ibm.com>
Date: Sat, 31 Dec 2016 11:23:32 -0500
Subject: [PATCH 2/4] Introduce condition to notify waiters of completed
command
Introduce a lock and a condition to notify anyone waiting for the completion
of the execution of a TPM command by the backend (thread). The backend
uses the condition to signal anyone waiting for command completion.
We need to place the condition in two locations: one is invoked by the
backend thread, the other by the bottom half thread.
We will use the signalling to wait for command completion before VM
suspend.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Upstream-Status: Pending [https://lists.nongnu.org/archive/html/qemu-devel/2016-06/msg00252.html]
Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
---
hw/tpm/tpm_int.h | 3 +++
hw/tpm/tpm_tis.c | 14 ++++++++++++++
2 files changed, 17 insertions(+)
diff --git a/hw/tpm/tpm_int.h b/hw/tpm/tpm_int.h
index 6b2c9c953a..70be1ad8d9 100644
--- a/hw/tpm/tpm_int.h
+++ b/hw/tpm/tpm_int.h
@@ -30,6 +30,9 @@ struct TPMState {
char *backend;
TPMBackend *be_driver;
TPMVersion be_tpm_version;
+
+ QemuMutex state_lock;
+ QemuCond cmd_complete;
};
#define TPM(obj) OBJECT_CHECK(TPMState, (obj), TYPE_TPM_TIS)
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
index 381e7266ea..14d9e83ea2 100644
--- a/hw/tpm/tpm_tis.c
+++ b/hw/tpm/tpm_tis.c
@@ -368,6 +368,8 @@ static void tpm_tis_receive_bh(void *opaque)
TPMTISEmuState *tis = &s->s.tis;
uint8_t locty = s->locty_number;
+ qemu_mutex_lock(&s->state_lock);
+
tpm_tis_sts_set(&tis->loc[locty],
TPM_TIS_STS_VALID | TPM_TIS_STS_DATA_AVAILABLE);
tis->loc[locty].state = TPM_TIS_STATE_COMPLETION;
@@ -384,6 +386,10 @@ static void tpm_tis_receive_bh(void *opaque)
tpm_tis_raise_irq(s, locty,
TPM_TIS_INT_DATA_AVAILABLE | TPM_TIS_INT_STS_VALID);
#endif
+
+ /* notify of completed command */
+ qemu_cond_signal(&s->cmd_complete);
+ qemu_mutex_unlock(&s->state_lock);
}
/*
@@ -403,6 +409,11 @@ static void tpm_tis_receive_cb(TPMState *s, uint8_t locty,
}
}
+ qemu_mutex_lock(&s->state_lock);
+ /* notify of completed command */
+ qemu_cond_signal(&s->cmd_complete);
+ qemu_mutex_unlock(&s->state_lock);
+
qemu_bh_schedule(tis->bh);
}
@@ -1072,6 +1083,9 @@ static void tpm_tis_initfn(Object *obj)
memory_region_init_io(&s->mmio, OBJECT(s), &tpm_tis_memory_ops,
s, "tpm-tis-mmio",
TPM_TIS_NUM_LOCALITIES << TPM_TIS_LOCALITY_SHIFT);
+
+ qemu_mutex_init(&s->state_lock);
+ qemu_cond_init(&s->cmd_complete);
}
static void tpm_tis_class_init(ObjectClass *klass, void *data)
--
2.11.0