Commit 020a0d8f authored by Jonathan McDowell's avatar Jonathan McDowell Committed by Jarkko Sakkinen
Browse files

tpm: Remove tpm_find_get_ops 



tpm_find_get_ops() looks for the first valid TPM if the caller passes in
NULL. All internal users have been converted to either associate
themselves with a TPM directly, or call tpm_default_chip() as part of
their setup. Remove the no longer necessary tpm_find_get_ops().

Reviewed-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: default avatarJonathan McDowell <noodles@meta.com>
Signed-off-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
parent e68407b6

drivers/char/tpm/tpm-chip.c

+0 −36
Original line number Diff line number Diff line
@@ -230,42 +230,6 @@ struct tpm_chip *tpm_default_chip(void) 
}

EXPORT_SYMBOL_GPL(tpm_default_chip);



/**

 * tpm_find_get_ops() - find and reserve a TPM chip

 * @chip:	a &struct tpm_chip instance, %NULL for the default chip

 *

 * Finds a TPM chip and reserves its class device and operations. The chip must

 * be released with tpm_put_ops() after use.

 * This function is for internal use only. It supports existing TPM callers

 * by accepting NULL, but those callers should be converted to pass in a chip

 * directly.

 *

 * Return:

 * A reserved &struct tpm_chip instance.

 * %NULL if a chip is not found.

 * %NULL if the chip is not available.

 */

struct tpm_chip *tpm_find_get_ops(struct tpm_chip *chip)

{

	int rc;



	if (chip) {

		if (!tpm_try_get_ops(chip))

			return chip;

		return NULL;

	}



	chip = tpm_default_chip();

	if (!chip)

		return NULL;

	rc = tpm_try_get_ops(chip);

	/* release additional reference we got from tpm_default_chip() */

	put_device(&chip->dev);

	if (rc)

		return NULL;

	return chip;

}



/**

 * tpm_dev_release() - free chip memory and the device number

 * @dev: the character device for the TPM chip

drivers/char/tpm/tpm-interface.c

+16 −4
Original line number Diff line number Diff line
@@ -313,10 +313,13 @@ int tpm_is_tpm2(struct tpm_chip *chip) 
{

	int rc;



	chip = tpm_find_get_ops(chip);

	if (!chip)

		return -ENODEV;



	rc = tpm_try_get_ops(chip);

	if (rc)

		return rc;



	rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;



	tpm_put_ops(chip);
@@ -338,10 +341,13 @@ int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_idx, 
{

	int rc;



	chip = tpm_find_get_ops(chip);

	if (!chip)

		return -ENODEV;



	rc = tpm_try_get_ops(chip);

	if (rc)

		return rc;



	if (chip->flags & TPM_CHIP_FLAG_TPM2)

		rc = tpm2_pcr_read(chip, pcr_idx, digest, NULL);

	else
@@ -369,10 +375,13 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, 
	int rc;

	int i;



	chip = tpm_find_get_ops(chip);

	if (!chip)

		return -ENODEV;



	rc = tpm_try_get_ops(chip);

	if (rc)

		return rc;



	for (i = 0; i < chip->nr_allocated_banks; i++) {

		if (digests[i].alg_id != chip->allocated_banks[i].alg_id) {

			rc = -EINVAL;
@@ -492,10 +501,13 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max) 
	if (!out || max > TPM_MAX_RNG_DATA)

		return -EINVAL;



	chip = tpm_find_get_ops(chip);

	if (!chip)

		return -ENODEV;



	rc = tpm_try_get_ops(chip);

	if (rc)

		return rc;



	if (chip->flags & TPM_CHIP_FLAG_TPM2)

		rc = tpm2_get_random(chip, out, max);

	else

drivers/char/tpm/tpm.h

+0 −1
Original line number Diff line number Diff line
@@ -267,7 +267,6 @@ static inline void tpm_msleep(unsigned int delay_msec) 
int tpm_chip_bootstrap(struct tpm_chip *chip);

int tpm_chip_start(struct tpm_chip *chip);

void tpm_chip_stop(struct tpm_chip *chip);

struct tpm_chip *tpm_find_get_ops(struct tpm_chip *chip);



struct tpm_chip *tpm_chip_alloc(struct device *dev,

				const struct tpm_class_ops *ops);

drivers/char/tpm/tpm_tis_core.c

+1 −2
Original line number Diff line number Diff line
@@ -265,8 +265,7 @@ static u8 tpm_tis_status(struct tpm_chip *chip) 


			/*

			 * Dump stack for forensics, as invalid TPM_STS.x could be

			 * potentially triggered by impaired tpm_try_get_ops() or

			 * tpm_find_get_ops().

			 * potentially triggered by impaired tpm_try_get_ops().

			 */

			dump_stack();

		}