RE: [PATCH v9 16/17] tpm: take TPM chip power gating out of tpm_transmit()

From: Winkler, Tomas
Date: Sun Nov 18 2018 - 17:53:20 EST




>
> Call tpm_chip_start() and tpm_chip_stop() in
>
> * tpm_try_get_ops() and tpm_put_ops()
> * tpm_chip_register()
> * tpm2_del_space()
>
> And remove these calls from tpm_transmit(). The core reason for this change
> is that in tpm_vtpm_proxy a locality change requires a virtual TPM command
> (a command made up just for that driver).
>
> The consequence of this is that this commit removes the remaining nested
> calls.
>
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>

This is still NACK from my side
Tomas

> ---
> drivers/char/tpm/tpm-chip.c | 25 ++++++++++++-------------
> drivers/char/tpm/tpm-interface.c | 4 ----
> drivers/char/tpm/tpm.h | 9 ---------
> drivers/char/tpm/tpm2-space.c | 5 ++++-
> drivers/char/tpm/tpm_vtpm_proxy.c | 3 +--
> 5 files changed, 17 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index
> 65f1561eba81..7ad4d9045e4c 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -41,9 +41,6 @@ static int tpm_request_locality(struct tpm_chip *chip,
> unsigned int flags) {
> int rc;
>
> - if (flags & TPM_TRANSMIT_NESTED)
> - return 0;
> -
> if (!chip->ops->request_locality)
> return 0;
>
> @@ -59,9 +56,6 @@ static void tpm_relinquish_locality(struct tpm_chip
> *chip, unsigned int flags) {
> int rc;
>
> - if (flags & TPM_TRANSMIT_NESTED)
> - return;
> -
> if (!chip->ops->relinquish_locality)
> return;
>
> @@ -74,9 +68,6 @@ static void tpm_relinquish_locality(struct tpm_chip
> *chip, unsigned int flags)
>
> static int tpm_cmd_ready(struct tpm_chip *chip, unsigned int flags) {
> - if (flags & TPM_TRANSMIT_NESTED)
> - return 0;
> -
> if (!chip->ops->cmd_ready)
> return 0;
>
> @@ -85,9 +76,6 @@ static int tpm_cmd_ready(struct tpm_chip *chip,
> unsigned int flags)
>
> static int tpm_go_idle(struct tpm_chip *chip, unsigned int flags) {
> - if (flags & TPM_TRANSMIT_NESTED)
> - return 0;
> -
> if (!chip->ops->go_idle)
> return 0;
>
> @@ -166,11 +154,17 @@ int tpm_try_get_ops(struct tpm_chip *chip)
>
> down_read(&chip->ops_sem);
> if (!chip->ops)
> - goto out_lock;
> + goto out_ops;
>
> mutex_lock(&chip->tpm_mutex);
> + rc = tpm_chip_start(chip, 0);
> + if (rc)
> + goto out_lock;
> +
> return 0;
> out_lock:
> + mutex_unlock(&chip->tpm_mutex);
> +out_ops:
> up_read(&chip->ops_sem);
> put_device(&chip->dev);
> return rc;
> @@ -186,6 +180,7 @@ EXPORT_SYMBOL_GPL(tpm_try_get_ops);
> */
> void tpm_put_ops(struct tpm_chip *chip) {
> + tpm_chip_stop(chip, 0);
> mutex_unlock(&chip->tpm_mutex);
> up_read(&chip->ops_sem);
> put_device(&chip->dev);
> @@ -563,7 +558,11 @@ int tpm_chip_register(struct tpm_chip *chip) {
> int rc;
>
> + rc = tpm_chip_start(chip, 0);
> + if (rc)
> + return rc;
> rc = tpm_auto_startup(chip);
> + tpm_chip_stop(chip, 0);
> if (rc)
> return rc;
>
> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-
> interface.c
> index 2c79284ffd4e..21ac8da94d90 100644
> --- a/drivers/char/tpm/tpm-interface.c
> +++ b/drivers/char/tpm/tpm-interface.c
> @@ -168,11 +168,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, u8
> *buf, size_t bufsiz,
> memcpy(save, buf, save_size);
>
> for (;;) {
> - ret = tpm_chip_start(chip, flags);
> - if (ret)
> - return ret;
> ret = tpm_try_transmit(chip, buf, bufsiz, flags);
> - tpm_chip_stop(chip, flags);
> if (ret < 0)
> break;
> rc = be32_to_cpu(header->return_code); diff --git
> a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index
> c42a75710b70..f9d56dfd0d20 100644
> --- a/drivers/char/tpm/tpm.h
> +++ b/drivers/char/tpm/tpm.h
> @@ -485,15 +485,6 @@ extern const struct file_operations tpm_fops;
> extern const struct file_operations tpmrm_fops; extern struct idr
> dev_nums_idr;
>
> -/**
> - * enum tpm_transmit_flags - flags for tpm_transmit()
> - *
> - * %TPM_TRANSMIT_NESTED: discard setup steps (power management,
> locality)
> - */
> -enum tpm_transmit_flags {
> - TPM_TRANSMIT_NESTED = BIT(0),
> -};
> -
> ssize_t tpm_transmit(struct tpm_chip *chip, u8 *buf, size_t bufsiz,
> unsigned int flags);
> ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_buf *buf, diff -
> -git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
> index ced1dc91ba6f..d913715d30aa 100644
> --- a/drivers/char/tpm/tpm2-space.c
> +++ b/drivers/char/tpm/tpm2-space.c
> @@ -60,7 +60,10 @@ int tpm2_init_space(struct tpm_space *space) void
> tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space) {
> mutex_lock(&chip->tpm_mutex);
> - tpm2_flush_sessions(chip, space);
> + if (!tpm_chip_start(chip, 0)) {
> + tpm2_flush_sessions(chip, space);
> + tpm_chip_stop(chip, 0);
> + }
> mutex_unlock(&chip->tpm_mutex);
> kfree(space->context_buf);
> kfree(space->session_buf);
> diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c
> b/drivers/char/tpm/tpm_vtpm_proxy.c
> index e8a1da2810a9..a4bb60e163cc 100644
> --- a/drivers/char/tpm/tpm_vtpm_proxy.c
> +++ b/drivers/char/tpm/tpm_vtpm_proxy.c
> @@ -417,8 +417,7 @@ static int vtpm_proxy_request_locality(struct
> tpm_chip *chip, int locality)
>
> proxy_dev->state |= STATE_DRIVER_COMMAND;
>
> - rc = tpm_transmit_cmd(chip, &buf, 0, TPM_TRANSMIT_NESTED,
> - "attempting to set locality");
> + rc = tpm_transmit_cmd(chip, &buf, 0, 0, "attempting to set locality");
>
> proxy_dev->state &= ~STATE_DRIVER_COMMAND;
>
> --
> 2.19.1