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@xxxxxxxxxxxxxxxxxx>
> > > 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
