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 <[email protected]> --- 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 --- 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. -- 2.13.6
