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[1/6] tpm: Introduce a kref for the tpm_chip

Message ID 20180620161948.1464255-2-stefanb@linux.vnet.ibm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Stefan Berger June 20, 2018, 4:19 p.m. UTC
Introduce a kref for the tpm_chip that we initialize when the tpm_chip has
been allocated and release before the tpm_chip is to be freed.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
---
 drivers/char/tpm/tpm-chip.c | 24 +++++++++++++++++++-----
 drivers/char/tpm/tpm.h      |  1 +
 2 files changed, 20 insertions(+), 5 deletions(-)

Comments

Jason Gunthorpe June 20, 2018, 6:38 p.m. UTC | #1
On Wed, Jun 20, 2018 at 12:19:43PM -0400, Stefan Berger wrote:
> Introduce a kref for the tpm_chip that we initialize when the tpm_chip has
> been allocated and release before the tpm_chip is to be freed.
> 
> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
>  drivers/char/tpm/tpm-chip.c | 24 +++++++++++++++++++-----
>  drivers/char/tpm/tpm.h      |  1 +
>  2 files changed, 20 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index 0a62c19937b6..a933676194a4 100644
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -119,8 +119,24 @@ struct tpm_chip *tpm_chip_find_get(struct tpm_chip *chip)
>  	return res;
>  }
>  
> +static void tpm_chip_free(struct kref *kref)
> +{
> +	struct tpm_chip *chip = container_of(kref, struct tpm_chip, kref);
> +
> +	kfree(chip->log.bios_event_log);
> +	kfree(chip->work_space.context_buf);
> +	kfree(chip->work_space.session_buf);
> +	kfree(chip);
> +}
> +
> +static void tpm_chip_put(struct tpm_chip *chip)
> +{
> +	if (chip)
> +		kref_put(&chip->kref, tpm_chip_free);
> +}
> +
>  /**
> - * tpm_dev_release() - free chip memory and the device number
> + * tpm_dev_release() - free the device number and release reference to chip
>   * @dev: the character device for the TPM chip
>   *
>   * This is used as the release function for the character device.
> @@ -133,10 +149,7 @@ static void tpm_dev_release(struct device *dev)
>  	idr_remove(&dev_nums_idr, chip->dev_num);
>  	mutex_unlock(&idr_lock);
>  
> -	kfree(chip->log.bios_event_log);
> -	kfree(chip->work_space.context_buf);
> -	kfree(chip->work_space.session_buf);
> -	kfree(chip);
> +	tpm_chip_put(chip);
>  }
>  static void tpm_devs_release(struct device *dev)
> @@ -195,6 +208,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
>  
>  	mutex_init(&chip->tpm_mutex);
>  	init_rwsem(&chip->ops_sem);
> +	kref_init(&chip->kref);
>  
>  	chip->ops = ops;
>  
> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> index 7f2d0f489e9c..098d7dcc04a4 100644
> +++ b/drivers/char/tpm/tpm.h
> @@ -211,6 +211,7 @@ struct tpm_chip {
>  	struct cdev cdev;
>  	struct cdev cdevs;
>  
> +	struct kref kref;

NAK, there is already a kref in struct device, that one must be used.

Jason
Stefan Berger June 20, 2018, 7:34 p.m. UTC | #2
On 06/20/2018 02:38 PM, Jason Gunthorpe wrote:
> On Wed, Jun 20, 2018 at 12:19:43PM -0400, Stefan Berger wrote:
>> Introduce a kref for the tpm_chip that we initialize when the tpm_chip has
>> been allocated and release before the tpm_chip is to be freed.
>>
>> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
>>   drivers/char/tpm/tpm-chip.c | 24 +++++++++++++++++++-----
>>   drivers/char/tpm/tpm.h      |  1 +
>>   2 files changed, 20 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
>> index 0a62c19937b6..a933676194a4 100644
>> +++ b/drivers/char/tpm/tpm-chip.c
>> @@ -119,8 +119,24 @@ struct tpm_chip *tpm_chip_find_get(struct tpm_chip *chip)
>>   	return res;
>>   }
>>   
>> +static void tpm_chip_free(struct kref *kref)
>> +{
>> +	struct tpm_chip *chip = container_of(kref, struct tpm_chip, kref);
>> +
>> +	kfree(chip->log.bios_event_log);
>> +	kfree(chip->work_space.context_buf);
>> +	kfree(chip->work_space.session_buf);
>> +	kfree(chip);
>> +}
>> +
>> +static void tpm_chip_put(struct tpm_chip *chip)
>> +{
>> +	if (chip)
>> +		kref_put(&chip->kref, tpm_chip_free);
>> +}
>> +
>>   /**
>> - * tpm_dev_release() - free chip memory and the device number
>> + * tpm_dev_release() - free the device number and release reference to chip
>>    * @dev: the character device for the TPM chip
>>    *
>>    * This is used as the release function for the character device.
>> @@ -133,10 +149,7 @@ static void tpm_dev_release(struct device *dev)
>>   	idr_remove(&dev_nums_idr, chip->dev_num);
>>   	mutex_unlock(&idr_lock);
>>   
>> -	kfree(chip->log.bios_event_log);
>> -	kfree(chip->work_space.context_buf);
>> -	kfree(chip->work_space.session_buf);
>> -	kfree(chip);
>> +	tpm_chip_put(chip);
>>   }
>>   static void tpm_devs_release(struct device *dev)
>> @@ -195,6 +208,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
>>   
>>   	mutex_init(&chip->tpm_mutex);
>>   	init_rwsem(&chip->ops_sem);
>> +	kref_init(&chip->kref);
>>   
>>   	chip->ops = ops;
>>   
>> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
>> index 7f2d0f489e9c..098d7dcc04a4 100644
>> +++ b/drivers/char/tpm/tpm.h
>> @@ -211,6 +211,7 @@ struct tpm_chip {
>>   	struct cdev cdev;
>>   	struct cdev cdevs;
>>   
>> +	struct kref kref;
> NAK, there is already a kref in struct device, that one must be used.

Right. Should make it simpler...


>
> Jason
>
Jarkko Sakkinen June 21, 2018, 4:50 p.m. UTC | #3
On Wed, Jun 20, 2018 at 03:34:36PM -0400, Stefan Berger wrote:
> On 06/20/2018 02:38 PM, Jason Gunthorpe wrote:
> > On Wed, Jun 20, 2018 at 12:19:43PM -0400, Stefan Berger wrote:
> > > Introduce a kref for the tpm_chip that we initialize when the tpm_chip has
> > > been allocated and release before the tpm_chip is to be freed.
> > > 
> > > Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
> > >   drivers/char/tpm/tpm-chip.c | 24 +++++++++++++++++++-----
> > >   drivers/char/tpm/tpm.h      |  1 +
> > >   2 files changed, 20 insertions(+), 5 deletions(-)
> > > 
> > > diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> > > index 0a62c19937b6..a933676194a4 100644
> > > +++ b/drivers/char/tpm/tpm-chip.c
> > > @@ -119,8 +119,24 @@ struct tpm_chip *tpm_chip_find_get(struct tpm_chip *chip)
> > >   	return res;
> > >   }
> > > +static void tpm_chip_free(struct kref *kref)
> > > +{
> > > +	struct tpm_chip *chip = container_of(kref, struct tpm_chip, kref);
> > > +
> > > +	kfree(chip->log.bios_event_log);
> > > +	kfree(chip->work_space.context_buf);
> > > +	kfree(chip->work_space.session_buf);
> > > +	kfree(chip);
> > > +}
> > > +
> > > +static void tpm_chip_put(struct tpm_chip *chip)
> > > +{
> > > +	if (chip)
> > > +		kref_put(&chip->kref, tpm_chip_free);
> > > +}
> > > +
> > >   /**
> > > - * tpm_dev_release() - free chip memory and the device number
> > > + * tpm_dev_release() - free the device number and release reference to chip
> > >    * @dev: the character device for the TPM chip
> > >    *
> > >    * This is used as the release function for the character device.
> > > @@ -133,10 +149,7 @@ static void tpm_dev_release(struct device *dev)
> > >   	idr_remove(&dev_nums_idr, chip->dev_num);
> > >   	mutex_unlock(&idr_lock);
> > > -	kfree(chip->log.bios_event_log);
> > > -	kfree(chip->work_space.context_buf);
> > > -	kfree(chip->work_space.session_buf);
> > > -	kfree(chip);
> > > +	tpm_chip_put(chip);
> > >   }
> > >   static void tpm_devs_release(struct device *dev)
> > > @@ -195,6 +208,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
> > >   	mutex_init(&chip->tpm_mutex);
> > >   	init_rwsem(&chip->ops_sem);
> > > +	kref_init(&chip->kref);
> > >   	chip->ops = ops;
> > > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> > > index 7f2d0f489e9c..098d7dcc04a4 100644
> > > +++ b/drivers/char/tpm/tpm.h
> > > @@ -211,6 +211,7 @@ struct tpm_chip {
> > >   	struct cdev cdev;
> > >   	struct cdev cdevs;
> > > +	struct kref kref;
> > NAK, there is already a kref in struct device, that one must be used.
> 
> Right. Should make it simpler...

I'll review the next version.

/Jarkko
diff mbox

Patch

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 0a62c19937b6..a933676194a4 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -119,8 +119,24 @@  struct tpm_chip *tpm_chip_find_get(struct tpm_chip *chip)
 	return res;
 }
 
+static void tpm_chip_free(struct kref *kref)
+{
+	struct tpm_chip *chip = container_of(kref, struct tpm_chip, kref);
+
+	kfree(chip->log.bios_event_log);
+	kfree(chip->work_space.context_buf);
+	kfree(chip->work_space.session_buf);
+	kfree(chip);
+}
+
+static void tpm_chip_put(struct tpm_chip *chip)
+{
+	if (chip)
+		kref_put(&chip->kref, tpm_chip_free);
+}
+
 /**
- * tpm_dev_release() - free chip memory and the device number
+ * tpm_dev_release() - free the device number and release reference to chip
  * @dev: the character device for the TPM chip
  *
  * This is used as the release function for the character device.
@@ -133,10 +149,7 @@  static void tpm_dev_release(struct device *dev)
 	idr_remove(&dev_nums_idr, chip->dev_num);
 	mutex_unlock(&idr_lock);
 
-	kfree(chip->log.bios_event_log);
-	kfree(chip->work_space.context_buf);
-	kfree(chip->work_space.session_buf);
-	kfree(chip);
+	tpm_chip_put(chip);
 }
 
 static void tpm_devs_release(struct device *dev)
@@ -195,6 +208,7 @@  struct tpm_chip *tpm_chip_alloc(struct device *pdev,
 
 	mutex_init(&chip->tpm_mutex);
 	init_rwsem(&chip->ops_sem);
+	kref_init(&chip->kref);
 
 	chip->ops = ops;
 
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 7f2d0f489e9c..098d7dcc04a4 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -211,6 +211,7 @@  struct tpm_chip {
 	struct cdev cdev;
 	struct cdev cdevs;
 
+	struct kref kref;
 	/* A driver callback under ops cannot be run unless ops_sem is held
 	 * (sometimes implicitly, eg for the sysfs code). ops becomes null
 	 * when the driver is unregistered, see tpm_try_get_ops.