Commit 304ff672 authored by Jarkko Sakkinen's avatar Jarkko Sakkinen
Browse files

tpm: clean up tpm_try_transmit() error handling flow 



Move locking, locality handling and power management to tpm_transmit()
in order to simplify the flow.

Signed-off-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: default avatarStefan Berger <stefanb@linux.ibm.com>
Tested-by: default avatarStefan Berger <stefanb@linux.ibm.com>
Reviewed-by: default avatarJerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
Tested-by: default avatarAlexander Steffen <Alexander.Steffen@infineon.com>
parent c4df71d4

drivers/char/tpm/tpm-interface.c

+43 −51
Original line number Diff line number Diff line
@@ -167,7 +167,6 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, struct tpm_space *space, 
	ssize_t len = 0;

	u32 count, ordinal;

	unsigned long stop;

	bool need_locality;



	rc = tpm_validate_command(chip, space, buf, bufsiz);

	if (rc == -EINVAL)
@@ -197,37 +196,16 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, struct tpm_space *space, 
		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);

	if (rc)

		goto out;

		return rc;



	rc = chip->ops->send(chip, buf, count);

	if (rc < 0) {

		if (rc != -EPIPE)

			dev_err(&chip->dev,

				"%s: send(): error %d\n", __func__, rc);

		goto out;

		goto out_rc;

	}



	/* A sanity check. send() should just return zero on success e.g.
@@ -252,7 +230,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, struct tpm_space *space, 
		if (chip->ops->req_canceled(chip, status)) {

			dev_err(&chip->dev, "Operation Canceled\n");

			rc = -ECANCELED;

			goto out;

			goto out_rc;

		}



		tpm_msleep(TPM_TIMEOUT_POLL);
@@ -262,40 +240,20 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, struct tpm_space *space, 
	chip->ops->cancel(chip);

	dev_err(&chip->dev, "Operation Timed out\n");

	rc = -ETIME;

	goto out;

	goto out_rc;



out_recv:

	len = chip->ops->recv(chip, buf, bufsiz);

	if (len < 0) {

		rc = len;

		dev_err(&chip->dev,

			"tpm_transmit: tpm_recv: error %d\n", rc);

		goto out;

	} else if (len < TPM_HEADER_SIZE) {

		rc = -EFAULT;

		goto out;

	}



	if (len != be32_to_cpu(header->length)) {

		dev_err(&chip->dev, "tpm_transmit: tpm_recv: error %d\n", rc);

	} else if (len < TPM_HEADER_SIZE || len != be32_to_cpu(header->length))

		rc = -EFAULT;

		goto out;

	}



out_rc:

	if (!rc)

		rc = tpm2_commit_space(chip, space, ordinal, buf, &len);



out:

	/* 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;

}
@@ -325,6 +283,7 @@ 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,
@@ -340,7 +299,40 @@ 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);



		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);

drivers/char/tpm/tpm.h

+1 −0
Original line number Diff line number Diff line
@@ -576,6 +576,7 @@ int tpm2_probe(struct tpm_chip *chip); 
int tpm2_find_cc(struct tpm_chip *chip, u32 cc);

int tpm2_init_space(struct tpm_space *space);

void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space);

void tpm2_flush_space(struct tpm_chip *chip);

int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc,

		       u8 *cmd);

int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space,

drivers/char/tpm/tpm2-space.c

+1 −1
Original line number Diff line number Diff line
@@ -162,7 +162,7 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf, 
	return 0;

}



static void tpm2_flush_space(struct tpm_chip *chip)

void tpm2_flush_space(struct tpm_chip *chip)

{

	struct tpm_space *space = &chip->work_space;

	int i;

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