diff mbox series

[v2,3/4] tpm: Implement tpm2_init to call when TPM_OPS_AUTO_STARTUP is not set

Message ID 20200213202329.898607-4-stefanb@linux.vnet.ibm.com (mailing list archive)
State New, archived
Headers show
Series Enable vTPM 2.0 for the IBM vTPM driver | expand

Commit Message

Stefan Berger Feb. 13, 2020, 8:23 p.m. UTC 
From: Stefan Berger <stefanb@linux.ibm.com>

Implement tpm2_init() that gets the TPM 2 timeouts and command durations
and command code attributes. This function is to be called in case the
TPM_OPS_AUTO_STARTUP flag is not set and therefore tpm2_auto_startup()
is not called.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
---
 drivers/char/tpm/tpm-interface.c |  5 ++++-
 drivers/char/tpm/tpm.h           |  1 +
 drivers/char/tpm/tpm2-cmd.c      | 14 ++++++++++++++
 3 files changed, 19 insertions(+), 1 deletion(-)

Comments

Jarkko Sakkinen Feb. 25, 2020, 5 p.m. UTC | #1 
On Thu, Feb 13, 2020 at 03:23:28PM -0500, Stefan Berger wrote:
> From: Stefan Berger <stefanb@linux.ibm.com>
> 
> Implement tpm2_init() that gets the TPM 2 timeouts and command durations
> and command code attributes. This function is to be called in case the
> TPM_OPS_AUTO_STARTUP flag is not set and therefore tpm2_auto_startup()
> is not called.
> 
> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>

The commit makes zero effort trying to explain what the heck tpm_init()
is and when it should be used and why the function name tpm2_init().

/Jarkko
Stefan Berger Feb. 25, 2020, 6:20 p.m. UTC | #2 
On 2/25/20 12:00 PM, Jarkko Sakkinen wrote:
> On Thu, Feb 13, 2020 at 03:23:28PM -0500, Stefan Berger wrote:
>> From: Stefan Berger <stefanb@linux.ibm.com>
>>
>> Implement tpm2_init() that gets the TPM 2 timeouts and command durations
>> and command code attributes. This function is to be called in case the
>> TPM_OPS_AUTO_STARTUP flag is not set and therefore tpm2_auto_startup()
>> is not called.
>>
>> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
> The commit makes zero effort trying to explain what the heck tpm_init()
> is and when it should be used and why the function name tpm2_init().

Are you saying the explanation of when to use tpm2_init above is not 
enough? 'bviously we are trying to cover the case of using the TPM 2 by 
a driver that doesn't use the TPM_OPS_AUTO_STARTUP flag and therefore 
the TPM 2 timeouts and command durations and command code attributes are 
not set as they would be if tpm2_auto_startup() was to be called and 
tpm2_init() is the alternative to call. I didn't like tpm2_init() 
either... any suggestions for a better name?

    Stefan


>
> /Jarkko
Jarkko Sakkinen Feb. 26, 2020, 3:02 p.m. UTC | #3 
On Tue, Feb 25, 2020 at 01:20:39PM -0500, Stefan Berger wrote:
> On 2/25/20 12:00 PM, Jarkko Sakkinen wrote:
> > On Thu, Feb 13, 2020 at 03:23:28PM -0500, Stefan Berger wrote:
> > > From: Stefan Berger <stefanb@linux.ibm.com>
> > > 
> > > Implement tpm2_init() that gets the TPM 2 timeouts and command durations
> > > and command code attributes. This function is to be called in case the
> > > TPM_OPS_AUTO_STARTUP flag is not set and therefore tpm2_auto_startup()
> > > is not called.
> > > 
> > > Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
> > The commit makes zero effort trying to explain what the heck tpm_init()
> > is and when it should be used and why the function name tpm2_init().
> 
> Are you saying the explanation of when to use tpm2_init above is not enough?
> 'bviously we are trying to cover the case of using the TPM 2 by a driver
> that doesn't use the TPM_OPS_AUTO_STARTUP flag and therefore the TPM 2
> timeouts and command durations and command code attributes are not set as
> they would be if tpm2_auto_startup() was to be called and tpm2_init() is the
> alternative to call. I didn't like tpm2_init() either... any suggestions for
> a better name?

I'm not getting what this commit is trying to do in the first place.

/Jarkko
Stefan Berger Feb. 26, 2020, 5:35 p.m. UTC | #4 
On 2/26/20 10:02 AM, Jarkko Sakkinen wrote:
> On Tue, Feb 25, 2020 at 01:20:39PM -0500, Stefan Berger wrote:
>> On 2/25/20 12:00 PM, Jarkko Sakkinen wrote:
>>> On Thu, Feb 13, 2020 at 03:23:28PM -0500, Stefan Berger wrote:
>>>> From: Stefan Berger <stefanb@linux.ibm.com>
>>>>
>>>> Implement tpm2_init() that gets the TPM 2 timeouts and command durations
>>>> and command code attributes. This function is to be called in case the
>>>> TPM_OPS_AUTO_STARTUP flag is not set and therefore tpm2_auto_startup()
>>>> is not called.
>>>>
>>>> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
>>> The commit makes zero effort trying to explain what the heck tpm_init()
>>> is and when it should be used and why the function name tpm2_init().
>> Are you saying the explanation of when to use tpm2_init above is not enough?
>> 'bviously we are trying to cover the case of using the TPM 2 by a driver
>> that doesn't use the TPM_OPS_AUTO_STARTUP flag and therefore the TPM 2
>> timeouts and command durations and command code attributes are not set as
>> they would be if tpm2_auto_startup() was to be called and tpm2_init() is the
>> alternative to call. I didn't like tpm2_init() either... any suggestions for
>> a better name?
> I'm not getting what this commit is trying to do in the first place.
I sent out v3, maybe the text there is better.
>
> /Jarkko
diff mbox series

Patch

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index a438b1206fcb..cca0e542172d 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -371,8 +371,11 @@  int tpm_auto_startup(struct tpm_chip *chip)
 {
 	int rc;
 
-	if (!(chip->ops->flags & TPM_OPS_AUTO_STARTUP))
+	if (!(chip->ops->flags & TPM_OPS_AUTO_STARTUP)) {
+		if (chip->flags & TPM_CHIP_FLAG_TPM2)
+			return tpm2_init(chip);
 		return 0;
+	}
 
 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
 		rc = tpm2_auto_startup(chip);
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 5620747da0cf..895f8a1e17d2 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -222,6 +222,7 @@  ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
 			u32 *value, const char *desc);
 
 ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip);
+int tpm2_init(struct tpm_chip *chip);
 int tpm2_auto_startup(struct tpm_chip *chip);
 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type);
 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal);
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 13696deceae8..d5b4b0449c23 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -709,6 +709,20 @@  static int tpm2_startup(struct tpm_chip *chip)
 	return rc;
 }
 
+/**
+ * tpm2_init - Get timeouts and command code attributes
+ *             in case tpm2_auto_startup is not used.
+ * @chip: TPM chip to use
+ *
+ * Return 0 on success, < 0 in case of fatal error.
+ */
+int tpm2_init(struct tpm_chip *chip)
+{
+	tpm2_get_timeouts(chip);
+
+	return tpm2_get_cc_attrs_tbl(chip);
+}
+
 /**
  * tpm2_auto_startup - Perform the standard automatic TPM initialization
  *                     sequence