[PATCH v9 11/17] tpm: move TPM space code out of tpm_transmit()

Jarkko Sakkinen
2018-11-18T12:49:40Z

Prepare and commit TPM space before and after calling tpm_transmit()
instead of doing that inside tpm_transmit(). After this change we can
remove TPM_TRANSMIT_NESTED flag from tpm2_prepare_space() and
tpm2_commit_space() and replace it with TPM_TRANSMIT_UNLOCKED.

Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
---
drivers/char/tpm/tpm-dev-common.c | 30 ++++++++++++++++++++++++++----
drivers/char/tpm/tpm-interface.c | 29 +++--------------------------
drivers/char/tpm/tpm2-space.c | 12 ++++++------
3 files changed, 35 insertions(+), 36 deletions(-)

diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c
index cbb0ee30b511..40c1cb09ebd2 100644
--- a/drivers/char/tpm/tpm-dev-common.c
+++ b/drivers/char/tpm/tpm-dev-common.c
@@ -30,13 +30,35 @@ static DEFINE_MUTEX(tpm_dev_wq_lock);
static ssize_t tpm_dev_transmit(struct tpm_chip *chip, struct tpm_space *space,
u8 *buf, size_t bufsiz)
{
- ssize_t ret;
+ struct tpm_header *header = (void *)buf;
+ ssize_t ret, len;

mutex_lock(&chip->tpm_mutex);
- ret = tpm_transmit(chip, space, buf, bufsiz, TPM_TRANSMIT_UNLOCKED);
- mutex_unlock(&chip->tpm_mutex);
+ ret = tpm2_prepare_space(chip, space, buf, bufsiz);
+ /* If the command is not implemented by the TPM, synthesize a
+ * response with a TPM2_RC_COMMAND_CODE return for user-space.
+ */
+ if (ret == -EOPNOTSUPP) {
+ header->length = cpu_to_be32(sizeof(*header));
+ header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
+ header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE |
+ TSS2_RESMGR_TPM_RC_LAYER);
+ ret = sizeof(*header);
+ }
+ if (ret)
+ goto out_lock;

- return ret;
+ len = tpm_transmit(chip, space, buf, bufsiz, TPM_TRANSMIT_UNLOCKED);
+ if (len < 0)
+ ret = len;
+
+ if (ret)
+ tpm2_flush_space(chip);
+ else
+ ret = tpm2_commit_space(chip, space, buf, &len);
+out_lock:
+ mutex_unlock(&chip->tpm_mutex);
+ return ret ? ret : len;
}

static void tpm_dev_async_work(struct work_struct *work)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index a6ffd0960ae5..7bec03e46043 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -147,27 +147,12 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
return -E2BIG;
}

- rc = tpm2_prepare_space(chip, space, buf, bufsiz);
- /*
- * If the command is not implemented by the TPM, synthesize a
- * response with a TPM2_RC_COMMAND_CODE return for user-space.
- */
- if (rc == -EOPNOTSUPP) {
- header->length = cpu_to_be32(sizeof(*header));
- header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
- header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE |
- TSS2_RESMGR_TPM_RC_LAYER);
- return sizeof(*header);
- }
- if (rc)
- return rc;
-
rc = chip->ops->send(chip, buf, count);
if (rc < 0) {
if (rc != -EPIPE)
dev_err(&chip->dev,
"%s: tpm_send: error %d\n", __func__, rc);
- goto out_space;
+ return rc;
}

if (chip->flags & TPM_CHIP_FLAG_IRQ)
@@ -182,8 +167,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,

if (chip->ops->req_canceled(chip, status)) {
dev_err(&chip->dev, "Operation Canceled\n");
- rc = -ECANCELED;
- goto out_space;
+ return -ECANCELED;
}

tpm_msleep(TPM_TIMEOUT_POLL);
@@ -192,8 +176,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,

chip->ops->cancel(chip);
dev_err(&chip->dev, "Operation Timed out\n");
- rc = -ETIME;
- goto out_space;
+ return -ETIME;

out_recv:
len = chip->ops->recv(chip, buf, bufsiz);
@@ -203,12 +186,6 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
} else if (len < TPM_HEADER_SIZE || len != be32_to_cpu(header->length))
rc = -EFAULT;

-out_space:
- if (rc)
- tpm2_flush_space(chip);
- else
- rc = tpm2_commit_space(chip, space, buf, &len);
-
return rc ? rc : len;
}

diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
index 172c9f9d4c29..995c8b963d65 100644
--- a/drivers/char/tpm/tpm2-space.c
+++ b/drivers/char/tpm/tpm2-space.c
@@ -39,7 +39,7 @@ static void tpm2_flush_sessions(struct tpm_chip *chip, struct tpm_space *space)
for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++) {
if (space->session_tbl[i])
tpm2_flush_context_cmd(chip, space->session_tbl[i],
- TPM_TRANSMIT_NESTED);
+ TPM_TRANSMIT_UNLOCKED);
}
}

@@ -84,7 +84,7 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
tpm_buf_append(&tbuf, &buf[*offset], body_size);

rc = tpm_transmit_cmd(chip, NULL, &tbuf, 4,
- TPM_TRANSMIT_NESTED, NULL);
+ TPM_TRANSMIT_UNLOCKED, NULL);
if (rc < 0) {
dev_warn(&chip->dev, "%s: failed with a system error %d\n",
__func__, rc);
@@ -133,7 +133,7 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
tpm_buf_append_u32(&tbuf, handle);

rc = tpm_transmit_cmd(chip, NULL, &tbuf, 0,
- TPM_TRANSMIT_NESTED, NULL);
+ TPM_TRANSMIT_UNLOCKED, NULL);
if (rc < 0) {
dev_warn(&chip->dev, "%s: failed with a system error %d\n",
__func__, rc);
@@ -170,7 +170,7 @@ void tpm2_flush_space(struct tpm_chip *chip)
for (i = 0; i < ARRAY_SIZE(space->context_tbl); i++)
if (space->context_tbl[i] && ~space->context_tbl[i])
tpm2_flush_context_cmd(chip, space->context_tbl[i],
- TPM_TRANSMIT_NESTED);
+ TPM_TRANSMIT_UNLOCKED);

tpm2_flush_sessions(chip, space);
}
@@ -419,7 +419,7 @@ static int tpm2_map_response_header(struct tpm_chip *chip, u32 cc, u8 *rsp,

return 0;
out_no_slots:
- tpm2_flush_context_cmd(chip, phandle, TPM_TRANSMIT_NESTED);
+ tpm2_flush_context_cmd(chip, phandle, TPM_TRANSMIT_UNLOCKED);
dev_warn(&chip->dev, "%s: out of slots for 0x%08X\n", __func__,
phandle);
return -ENOMEM;
@@ -507,7 +507,7 @@ static int tpm2_save_space(struct tpm_chip *chip)
return rc;

tpm2_flush_context_cmd(chip, space->context_tbl[i],
- TPM_TRANSMIT_NESTED);
+ TPM_TRANSMIT_UNLOCKED);
space->context_tbl[i] = ~0;
}

--
2.19.1