Messages in this thread | | | Subject | Re: [PATCH v3 06/16] tpm: clean up tpm_try_transmit() error handling flow | From | Stefan Berger <> | Date | Mon, 5 Nov 2018 17:20:33 -0500 |
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On 11/4/18 8:45 PM, Jarkko Sakkinen wrote: > Move locking, locality handling and power management to tpm_transmit() > in order to simplify the flow. > > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> > --- > drivers/char/tpm/tpm-interface.c | 90 ++++++++++++++------------------ > 1 file changed, 39 insertions(+), 51 deletions(-) > > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c > index ecda6f96cde0..0f343407daf8 100644 > --- a/drivers/char/tpm/tpm-interface.c > +++ b/drivers/char/tpm/tpm-interface.c > @@ -171,7 +171,6 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, > ssize_t len = 0; > u32 count, ordinal; > unsigned long stop; > - bool need_locality; > > rc = tpm_validate_command(chip, space, buf, bufsiz); > if (rc == -EINVAL) > @@ -201,30 +200,9 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, > return -E2BIG; > } > > - if (!(flags & TPM_TRANSMIT_UNLOCKED) && !(flags & TPM_TRANSMIT_NESTED)) > - mutex_lock(&chip->tpm_mutex); > - > - if (chip->ops->clk_enable != NULL) > - chip->ops->clk_enable(chip, true); > - > - /* Store the decision as chip->locality will be changed. */ > - need_locality = chip->locality == -1; > - > - if (need_locality) { > - rc = tpm_request_locality(chip, flags); > - if (rc < 0) { > - need_locality = false; > - goto out_locality; > - } > - } > - > - rc = tpm_cmd_ready(chip, flags); > - if (rc) > - goto out_locality; > - > rc = tpm2_prepare_space(chip, space, ordinal, buf);
tpm2_prepare_space() may issue TPM commands itself. Following your tree the move should now put the clk_enable() and tpm_request_locality() in the path. So, looks good.
> if (rc) > - goto out_idle; > + return rc; > > rc = chip->ops->send(chip, buf, count); > if (rc < 0) { > @@ -265,40 +243,16 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, > rc = len; > dev_err(&chip->dev, > "tpm_transmit: tpm_recv: error %d\n", rc); > - goto out_idle; > - } else if (len < TPM_HEADER_SIZE) { > - rc = -EFAULT; > - goto out_idle; > - } > - > - if (len != be32_to_cpu(header->length)) { > + tpm2_flush_space(chip); > + } else if (len < TPM_HEADER_SIZE || len != be32_to_cpu(header->length)) > rc = -EFAULT; > - goto out_idle; > - } > > out_space: > - if (rc) { > + if (rc) > tpm2_flush_space(chip); > - } else { > + else > rc = tpm2_commit_space(chip, space, ordinal, buf, &len); > - if (rc) > - dev_err(&chip->dev, "tpm2_commit_space: error %d\n", > - rc);
This should have been removed in the previous patch...
> - } > - > -out_idle: > - /* may fail but do not override previous error value in rc */ > - tpm_go_idle(chip, flags); > - > -out_locality: > - if (need_locality) > - tpm_relinquish_locality(chip, flags); > - > - if (chip->ops->clk_enable != NULL) > - chip->ops->clk_enable(chip, false); > > - if (!(flags & TPM_TRANSMIT_UNLOCKED) && !(flags & TPM_TRANSMIT_NESTED)) > - mutex_unlock(&chip->tpm_mutex); > return rc ? rc : len; > } > > @@ -328,6 +282,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space, > /* space for header and handles */ > u8 save[TPM_HEADER_SIZE + 3*sizeof(u32)]; > unsigned int delay_msec = TPM2_DURATION_SHORT; > + bool has_locality = false; > u32 rc = 0; > ssize_t ret; > const size_t save_size = min(space ? sizeof(save) : TPM_HEADER_SIZE, > @@ -343,7 +298,40 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space, > memcpy(save, buf, save_size); > > for (;;) { > + if (!(flags & TPM_TRANSMIT_UNLOCKED) && > + !(flags & TPM_TRANSMIT_NESTED)) > + mutex_lock(&chip->tpm_mutex); > + > + if (chip->ops->clk_enable != NULL) > + chip->ops->clk_enable(chip, true); > + > + if (chip->locality == -1) { > + ret = tpm_request_locality(chip, flags); > + if (ret) > + goto out_locality; > + has_locality = true; > + } > + > + ret = tpm_cmd_ready(chip, flags); > + if (ret) > + goto out_locality; > + > ret = tpm_try_transmit(chip, space, buf, bufsiz, flags); > + > + /* This may fail but do not override ret. */ > + tpm_go_idle(chip, flags); > + > +out_locality: > + if (has_locality) > + tpm_relinquish_locality(chip, flags);
Safer to also put has_locality = false here ?
> + > + if (chip->ops->clk_enable != NULL) > + chip->ops->clk_enable(chip, false); > + > + if (!(flags & TPM_TRANSMIT_UNLOCKED) && > + !(flags & TPM_TRANSMIT_NESTED)) > + mutex_unlock(&chip->tpm_mutex); > + > if (ret < 0) > break; > rc = be32_to_cpu(header->return_code);
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