[PATCH v3] crypto: ccp: Use scoped guard for mutex

From: Mario Limonciello
Date: Tue Dec 03 2024 - 11:24:39 EST


Use a scoped guard to simplify the cleanup handling.

Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
v3:
* Fix logic error
---
drivers/crypto/ccp/dbc.c | 53 +++++++++++++++-------------------------
1 file changed, 20 insertions(+), 33 deletions(-)

diff --git a/drivers/crypto/ccp/dbc.c b/drivers/crypto/ccp/dbc.c
index 5b105a23f6997..410084a9039c9 100644
--- a/drivers/crypto/ccp/dbc.c
+++ b/drivers/crypto/ccp/dbc.c
@@ -7,6 +7,8 @@
* Author: Mario Limonciello <mario.limonciello@xxxxxxx>
*/

+#include <linux/mutex.h>
+
#include "dbc.h"

#define DBC_DEFAULT_TIMEOUT (10 * MSEC_PER_SEC)
@@ -137,64 +139,49 @@ static long dbc_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return -ENODEV;
dbc_dev = psp_master->dbc_data;

- mutex_lock(&dbc_dev->ioctl_mutex);
+ guard(mutex)(&dbc_dev->ioctl_mutex);

switch (cmd) {
case DBCIOCNONCE:
- if (copy_from_user(dbc_dev->payload, argp, sizeof(struct dbc_user_nonce))) {
- ret = -EFAULT;
- goto unlock;
- }
+ if (copy_from_user(dbc_dev->payload, argp, sizeof(struct dbc_user_nonce)))
+ return -EFAULT;

ret = send_dbc_nonce(dbc_dev);
if (ret)
- goto unlock;
+ return ret;

- if (copy_to_user(argp, dbc_dev->payload, sizeof(struct dbc_user_nonce))) {
- ret = -EFAULT;
- goto unlock;
- }
+ if (copy_to_user(argp, dbc_dev->payload, sizeof(struct dbc_user_nonce)))
+ return -EFAULT;
break;
case DBCIOCUID:
- if (copy_from_user(dbc_dev->payload, argp, sizeof(struct dbc_user_setuid))) {
- ret = -EFAULT;
- goto unlock;
- }
+ if (copy_from_user(dbc_dev->payload, argp, sizeof(struct dbc_user_setuid)))
+ return -EFAULT;

*dbc_dev->payload_size = dbc_dev->header_size + sizeof(struct dbc_user_setuid);
ret = send_dbc_cmd(dbc_dev, PSP_DYNAMIC_BOOST_SET_UID);
if (ret)
- goto unlock;
+ return ret;

- if (copy_to_user(argp, dbc_dev->payload, sizeof(struct dbc_user_setuid))) {
- ret = -EFAULT;
- goto unlock;
- }
+ if (copy_to_user(argp, dbc_dev->payload, sizeof(struct dbc_user_setuid)))
+ return -EFAULT;
break;
case DBCIOCPARAM:
- if (copy_from_user(dbc_dev->payload, argp, sizeof(struct dbc_user_param))) {
- ret = -EFAULT;
- goto unlock;
- }
+ if (copy_from_user(dbc_dev->payload, argp, sizeof(struct dbc_user_param)))
+ return -EFAULT;

*dbc_dev->payload_size = dbc_dev->header_size + sizeof(struct dbc_user_param);
ret = send_dbc_parameter(dbc_dev);
if (ret)
- goto unlock;
+ return ret;

- if (copy_to_user(argp, dbc_dev->payload, sizeof(struct dbc_user_param))) {
- ret = -EFAULT;
- goto unlock;
- }
+ if (copy_to_user(argp, dbc_dev->payload, sizeof(struct dbc_user_param)))
+ return -EFAULT;
break;
default:
- ret = -EINVAL;
-
+ return -EINVAL;
}
-unlock:
- mutex_unlock(&dbc_dev->ioctl_mutex);

- return ret;
+ return 0;
}

static const struct file_operations dbc_fops = {

base-commit: 40384c840ea1944d7c5a392e8975ed088ecf0b37
--
2.43.0