From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nayna Jain Subject: [PATCH 2/4] tpm: define __wait_for_tpm_stat to specify variable polling sleep time Date: Wed, 6 Sep 2017 08:56:41 -0400 Message-ID: <20170906125643.5070-7-nayna@linux.vnet.ibm.com> References: <20170906125643.5070-1-nayna@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170906125643.5070-1-nayna-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tpmdd-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Cc: patrickc-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, jarkko.sakkinen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ima-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: tpmdd-devel@lists.sourceforge.net The existing wait_for_tpm_stat() checks the chip status before sleeping for 5 msec in a polling loop. For some functions although the status isn't ready immediately, the status returns extremely quickly. Waiting for 5 msec causes an unnecessary delay. An example is the send() call in the tpms_tis driver. This patch defines __wait_for_tpm_stat(), allowing the caller to specify the polling sleep timeout value within the loop. The existing wait_for_tpm_stat() becomes a wrapper for this function. Signed-off-by: Nayna Jain --- drivers/char/tpm/tpm-interface.c | 15 ++++++++++++--- drivers/char/tpm/tpm.h | 3 +++ drivers/char/tpm/tpm_tis_core.c | 11 ++++++----- 3 files changed, 21 insertions(+), 8 deletions(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 1d6729be4cd6..b23d006243b7 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -1050,8 +1050,9 @@ static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, return false; } -int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, - wait_queue_head_t *queue, bool check_cancel) +int __wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, + unsigned int poll_sleep, wait_queue_head_t *queue, + bool check_cancel) { unsigned long stop; long rc; @@ -1085,7 +1086,7 @@ int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, } } else { do { - tpm_msleep(TPM_TIMEOUT); + tpm_msleep(poll_sleep); status = chip->ops->status(chip); if ((status & mask) == mask) return 0; @@ -1093,6 +1094,14 @@ int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, } return -ETIME; } +EXPORT_SYMBOL_GPL(__wait_for_tpm_stat); + +int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, + wait_queue_head_t *queue, bool check_cancel) +{ + return __wait_for_tpm_stat(chip, mask, timeout, TPM_TIMEOUT, + queue, check_cancel); +} EXPORT_SYMBOL_GPL(wait_for_tpm_stat); #define TPM_ORD_SAVESTATE 152 diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 2d5466a72e40..eb2f8818eded 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -525,6 +525,9 @@ int tpm_do_selftest(struct tpm_chip *chip); unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal); int tpm_pm_suspend(struct device *dev); int tpm_pm_resume(struct device *dev); +int __wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, + unsigned long timeout, unsigned int poll_sleep, + wait_queue_head_t *queue, bool check_cancel); int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, wait_queue_head_t *queue, bool check_cancel); diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 6b9bf4c4d434..d1eab29cb447 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -268,8 +268,8 @@ static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len) status = tpm_tis_status(chip); if ((status & TPM_STS_COMMAND_READY) == 0) { tpm_tis_ready(chip); - if (wait_for_tpm_stat - (chip, TPM_STS_COMMAND_READY, chip->timeout_b, + if (__wait_for_tpm_stat + (chip, TPM_STS_COMMAND_READY, chip->timeout_b, 1, &priv->int_queue, false) < 0) { rc = -ETIME; goto out_err; @@ -303,7 +303,8 @@ static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len) if (ignore_burst_count) continue; - if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, + if (__wait_for_tpm_stat(chip, TPM_STS_VALID, + chip->timeout_c, 1, &priv->int_queue, false) < 0) { rc = -ETIME; goto out_err; @@ -320,8 +321,8 @@ static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len) if (rc < 0) goto out_err; - if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, - &priv->int_queue, false) < 0) { + if (__wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, + 1, &priv->int_queue, false) < 0) { rc = -ETIME; goto out_err; } -- 2.13.3 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot