v1->v2:
- move the caching to the backend layer since detecting the
TPM 1.2 TSC_ResetEstablishmentBit() command is easier to do
here.
---
hw/tpm/tpm_emulator.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)
diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
index 9aaec8e..507e2cb 100644
--- a/hw/tpm/tpm_emulator.c
+++ b/hw/tpm/tpm_emulator.c
@@ -71,6 +71,9 @@ typedef struct TPMEmulator {
ptm_cap caps; /* capabilities of the TPM */
uint8_t cur_locty_number; /* last set locality */
Error *migration_blocker;
+
+ unsigned int established_flag:1;
+ unsigned int established_flag_cached:1;
} TPMEmulator;
@@ -277,16 +280,22 @@ static bool
tpm_emulator_get_tpm_established_flag(TPMBackend *tb)
TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
ptm_est est;
- DPRINTF("%s", __func__);
+ if (tpm_emu->established_flag_cached) {
+ return tpm_emu->established_flag;
+ }
+
if (tpm_emulator_ctrlcmd(&tpm_emu->ctrl_chr, CMD_GET_TPMESTABLISHED, &est,
0, sizeof(est)) < 0) {
error_report("tpm-emulator: Could not get the TPM established flag:
%s",
strerror(errno));
return false;
}
- DPRINTF("established flag: %0x", est.u.resp.bit);
+ DPRINTF("got established flag: %0x", est.u.resp.bit);
+
+ tpm_emu->established_flag_cached = 1;
+ tpm_emu->established_flag = (est.u.resp.bit != 0);
- return (est.u.resp.bit != 0);
+ return tpm_emu->established_flag;
}
static int tpm_emulator_reset_tpm_established_flag(TPMBackend *tb,
@@ -317,6 +326,8 @@ static int
tpm_emulator_reset_tpm_established_flag(TPMBackend *tb,
return -1;
}
+ tpm_emu->established_flag_cached = 0;
+
return 0;
}