diff mbox

[v7,3/5] tpm: Clean up reading of timeout and duration capabilities

Message ID 1466474042-110773-4-git-send-email-eswierk@skyportsystems.com
State New, archived
Headers show

Commit Message

Ed Swierk June 21, 2016, 1:54 a.m. UTC
Call tpm_getcap() from tpm_get_timeouts() to eliminate redundant
code. Return all errors to the caller rather than swallowing them
(e.g. when tpm_transmit_cmd() returns nonzero).

Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>
---
 drivers/char/tpm/tpm-interface.c | 74 +++++++++++++++-------------------------
 1 file changed, 27 insertions(+), 47 deletions(-)

Comments

Jarkko Sakkinen June 21, 2016, 8:52 p.m. UTC | #1
On Mon, Jun 20, 2016 at 06:54:00PM -0700, Ed Swierk wrote:
> Call tpm_getcap() from tpm_get_timeouts() to eliminate redundant
> code. Return all errors to the caller rather than swallowing them
> (e.g. when tpm_transmit_cmd() returns nonzero).
> 
> Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>

Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

/Jarkko

> ---
>  drivers/char/tpm/tpm-interface.c | 74 +++++++++++++++-------------------------
>  1 file changed, 27 insertions(+), 47 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> index cc1e5bc..73c3ee0 100644
> --- a/drivers/char/tpm/tpm-interface.c
> +++ b/drivers/char/tpm/tpm-interface.c
> @@ -461,9 +461,19 @@ ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
>  		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
>  		tpm_cmd.params.getcap_in.subcap = subcap_id;
>  	}
> +
>  	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
> +
> +	if (!rc &&
> +	    ((subcap_id == TPM_CAP_PROP_TIS_TIMEOUT &&
> +	      be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 5) ||
> +	     (subcap_id == TPM_CAP_PROP_TIS_DURATION &&
> +	      be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 4)))
> +		rc = -EINVAL;
> +
>  	if (!rc)
>  		*cap = tpm_cmd.params.getcap_out.cap;
> +
>  	return rc;
>  }
>  
> @@ -504,48 +514,30 @@ static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
>  
>  int tpm_get_timeouts(struct tpm_chip *chip)
>  {
> -	struct tpm_cmd_t tpm_cmd;
> +	cap_t cap;
>  	unsigned long new_timeout[4];
>  	unsigned long old_timeout[4];
> -	struct duration_t *duration_cap;
>  	ssize_t rc;
>  
> -	tpm_cmd.header.in = tpm_getcap_header;
> -	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
> -	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
> -	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
> -	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
> -
> +	rc = tpm_getcap(chip->pdev, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
> +			"attempting to determine the timeouts");
>  	if (rc == TPM_ERR_INVALID_POSTINIT) {
>  		/* The TPM is not started, we are the first to talk to it.
>  		   Execute a startup command. */
> -		dev_info(chip->pdev, "Issuing TPM_STARTUP");
> +		dev_info(chip->pdev, "Issuing TPM_STARTUP\n");
>  		if (tpm_startup(chip, TPM_ST_CLEAR))
>  			return rc;
>  
> -		tpm_cmd.header.in = tpm_getcap_header;
> -		tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
> -		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
> -		tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
> -		rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
> -				  NULL);
> -	}
> -	if (rc) {
> -		dev_err(chip->pdev,
> -			"A TPM error (%zd) occurred attempting to determine the timeouts\n",
> -			rc);
> -		goto duration;
> +		rc = tpm_getcap(chip->pdev, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
> +				"attempting to determine the timeouts");
>  	}
> +	if (rc)
> +		return rc;
>  
> -	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
> -	    be32_to_cpu(tpm_cmd.header.out.length)
> -	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
> -		return -EINVAL;
> -
> -	old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
> -	old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
> -	old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
> -	old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
> +	old_timeout[0] = be32_to_cpu(cap.timeout.a);
> +	old_timeout[1] = be32_to_cpu(cap.timeout.b);
> +	old_timeout[2] = be32_to_cpu(cap.timeout.c);
> +	old_timeout[3] = be32_to_cpu(cap.timeout.d);
>  	memcpy(new_timeout, old_timeout, sizeof(new_timeout));
>  
>  	/*
> @@ -583,29 +575,17 @@ int tpm_get_timeouts(struct tpm_chip *chip)
>  	chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]);
>  	chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]);
>  
> -duration:
> -	tpm_cmd.header.in = tpm_getcap_header;
> -	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
> -	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
> -	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
> -
> -	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
> -			      "attempting to determine the durations");
> +	rc = tpm_getcap(chip->pdev, TPM_CAP_PROP_TIS_DURATION, &cap,
> +			"attempting to determine the durations");
>  	if (rc)
>  		return rc;
>  
> -	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
> -	    be32_to_cpu(tpm_cmd.header.out.length)
> -	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
> -		return -EINVAL;
> -
> -	duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
>  	chip->vendor.duration[TPM_SHORT] =
> -	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
> +		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
>  	chip->vendor.duration[TPM_MEDIUM] =
> -	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
> +		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
>  	chip->vendor.duration[TPM_LONG] =
> -	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
> +		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
>  
>  	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
>  	 * value wrong and apparently reports msecs rather than usecs. So we
> -- 
> 1.9.1
> 
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Ed Swierk June 22, 2016, 12:21 a.m. UTC | #2
On Mon, Jun 20, 2016 at 6:54 PM, Ed Swierk <eswierk@skyportsystems.com> wrote:
> --- a/drivers/char/tpm/tpm-interface.c
> +++ b/drivers/char/tpm/tpm-interface.c
> @@ -461,9 +461,19 @@ ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
>                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
>                 tpm_cmd.params.getcap_in.subcap = subcap_id;
>         }
> +
>         rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
> +
> +       if (!rc &&
> +           ((subcap_id == TPM_CAP_PROP_TIS_TIMEOUT &&
> +             be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 5) ||
> +            (subcap_id == TPM_CAP_PROP_TIS_DURATION &&
> +             be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 4)))
> +               rc = -EINVAL;
> +

Woops, a totally innocuous last-minute (post-testing) cleanup broke
this code; should be TPM_HEADER_SIZE + 20 and + 16. I'll push out v8
as soon as I redo my tests.

--Ed
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Jarkko Sakkinen June 22, 2016, 10:46 a.m. UTC | #3
On Tue, Jun 21, 2016 at 05:21:27PM -0700, Ed Swierk wrote:
> On Mon, Jun 20, 2016 at 6:54 PM, Ed Swierk <eswierk@skyportsystems.com> wrote:
> > --- a/drivers/char/tpm/tpm-interface.c
> > +++ b/drivers/char/tpm/tpm-interface.c
> > @@ -461,9 +461,19 @@ ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
> >                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
> >                 tpm_cmd.params.getcap_in.subcap = subcap_id;
> >         }
> > +
> >         rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
> > +
> > +       if (!rc &&
> > +           ((subcap_id == TPM_CAP_PROP_TIS_TIMEOUT &&
> > +             be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 5) ||
> > +            (subcap_id == TPM_CAP_PROP_TIS_DURATION &&
> > +             be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 4)))
> > +               rc = -EINVAL;
> > +
> 
> Woops, a totally innocuous last-minute (post-testing) cleanup broke
> this code; should be TPM_HEADER_SIZE + 20 and + 16. I'll push out v8
> as soon as I redo my tests.

OK, that's cool. Haven't yet got into testing it anyway.

1. This is too late for 4.8 release.
2. I'm on four week leave starting from week after next week but before
   I go to my leave I will apply these commits to my master branch so that
   they get exposure.
3. I try to do testing for my part before going to the leave.

> --Ed

/Jarkko
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diff mbox

Patch

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index cc1e5bc..73c3ee0 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -461,9 +461,19 @@  ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 		tpm_cmd.params.getcap_in.subcap = subcap_id;
 	}
+
 	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
+
+	if (!rc &&
+	    ((subcap_id == TPM_CAP_PROP_TIS_TIMEOUT &&
+	      be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 5) ||
+	     (subcap_id == TPM_CAP_PROP_TIS_DURATION &&
+	      be32_to_cpu(tpm_cmd.header.out.length) != TPM_HEADER_SIZE + 4)))
+		rc = -EINVAL;
+
 	if (!rc)
 		*cap = tpm_cmd.params.getcap_out.cap;
+
 	return rc;
 }
 
@@ -504,48 +514,30 @@  static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
 
 int tpm_get_timeouts(struct tpm_chip *chip)
 {
-	struct tpm_cmd_t tpm_cmd;
+	cap_t cap;
 	unsigned long new_timeout[4];
 	unsigned long old_timeout[4];
-	struct duration_t *duration_cap;
 	ssize_t rc;
 
-	tpm_cmd.header.in = tpm_getcap_header;
-	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
-	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
-	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
-	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
-
+	rc = tpm_getcap(chip->pdev, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
+			"attempting to determine the timeouts");
 	if (rc == TPM_ERR_INVALID_POSTINIT) {
 		/* The TPM is not started, we are the first to talk to it.
 		   Execute a startup command. */
-		dev_info(chip->pdev, "Issuing TPM_STARTUP");
+		dev_info(chip->pdev, "Issuing TPM_STARTUP\n");
 		if (tpm_startup(chip, TPM_ST_CLEAR))
 			return rc;
 
-		tpm_cmd.header.in = tpm_getcap_header;
-		tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
-		tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
-		tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
-		rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
-				  NULL);
-	}
-	if (rc) {
-		dev_err(chip->pdev,
-			"A TPM error (%zd) occurred attempting to determine the timeouts\n",
-			rc);
-		goto duration;
+		rc = tpm_getcap(chip->pdev, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
+				"attempting to determine the timeouts");
 	}
+	if (rc)
+		return rc;
 
-	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
-	    be32_to_cpu(tpm_cmd.header.out.length)
-	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
-		return -EINVAL;
-
-	old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
-	old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
-	old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
-	old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
+	old_timeout[0] = be32_to_cpu(cap.timeout.a);
+	old_timeout[1] = be32_to_cpu(cap.timeout.b);
+	old_timeout[2] = be32_to_cpu(cap.timeout.c);
+	old_timeout[3] = be32_to_cpu(cap.timeout.d);
 	memcpy(new_timeout, old_timeout, sizeof(new_timeout));
 
 	/*
@@ -583,29 +575,17 @@  int tpm_get_timeouts(struct tpm_chip *chip)
 	chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]);
 	chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]);
 
-duration:
-	tpm_cmd.header.in = tpm_getcap_header;
-	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
-	tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
-	tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
-
-	rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
-			      "attempting to determine the durations");
+	rc = tpm_getcap(chip->pdev, TPM_CAP_PROP_TIS_DURATION, &cap,
+			"attempting to determine the durations");
 	if (rc)
 		return rc;
 
-	if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
-	    be32_to_cpu(tpm_cmd.header.out.length)
-	    != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
-		return -EINVAL;
-
-	duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 	chip->vendor.duration[TPM_SHORT] =
-	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
+		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
 	chip->vendor.duration[TPM_MEDIUM] =
-	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
+		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
 	chip->vendor.duration[TPM_LONG] =
-	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
+		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
 
 	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 	 * value wrong and apparently reports msecs rather than usecs. So we