From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33806) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eEj8e-00024g-K4 for qemu-devel@nongnu.org; Tue, 14 Nov 2017 16:53:01 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eEj8b-00010P-5S for qemu-devel@nongnu.org; Tue, 14 Nov 2017 16:53:00 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:40750 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eEj8J-0000lZ-AH for qemu-devel@nongnu.org; Tue, 14 Nov 2017 16:52:56 -0500 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vAELnhcX057514 for ; Tue, 14 Nov 2017 16:52:35 -0500 Received: from e13.ny.us.ibm.com (e13.ny.us.ibm.com [129.33.205.203]) by mx0b-001b2d01.pphosted.com with ESMTP id 2e87fw3cmq-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 14 Nov 2017 16:52:34 -0500 Received: from localhost by e13.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 14 Nov 2017 16:52:34 -0500 From: Stefan Berger Date: Tue, 14 Nov 2017 16:52:27 -0500 In-Reply-To: <1510696349-5151-1-git-send-email-stefanb@linux.vnet.ibm.com> References: <1510696349-5151-1-git-send-email-stefanb@linux.vnet.ibm.com> Message-Id: <1510696349-5151-2-git-send-email-stefanb@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH v3 for-2.11 1/3] tpm_emulator: Add a caching layer for the TPM Established flag List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: marcandre.lureau@gmail.com, qemu-devel@nongnu.org, amarnath.valluri@intel.com Cc: Stefan Berger Add a caching layer for the TPM established flag so that we don't need to go to the emulator every time the flag is read by accessing the REG_ACCESS register. Signed-off-by: Stefan Berger 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 e1a6810..b293db7 100644 --- a/hw/tpm/tpm_emulator.c +++ b/hw/tpm/tpm_emulator.c @@ -73,6 +73,9 @@ typedef struct TPMEmulator { Error *migration_blocker; QemuMutex mutex; + + unsigned int established_flag:1; + unsigned int established_flag_cached:1; } TPMEmulator; @@ -287,16 +290,22 @@ 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, 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, @@ -327,6 +336,8 @@ static int tpm_emulator_reset_tpm_established_flag(TPMBackend *tb, return -1; } + tpm_emu->established_flag_cached = 0; + return 0; } -- 2.5.5