diff mbox series

[v2] crypto: ccp: Use scoped guard for mutex

Message ID 20241130135836.338-1-mario.limonciello@amd.com (mailing list archive)
State Superseded
Delegated to: Herbert Xu
Headers show
Series [v2] crypto: ccp: Use scoped guard for mutex | expand

Commit Message

Mario Limonciello Nov. 30, 2024, 1:58 p.m. UTC 
Use a scoped guard to simplify the cleanup handling.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
v2:
 * return immediately in default case
---
 drivers/crypto/ccp/dbc.c | 53 ++++++++++++++--------------------------
 1 file changed, 19 insertions(+), 34 deletions(-)

Comments

Tom Lendacky Dec. 2, 2024, 2:43 p.m. UTC | #1 
On 11/30/24 07:58, Mario Limonciello wrote:
> Use a scoped guard to simplify the cleanup handling.
> 
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> ---
> v2:
>  * return immediately in default case
> ---
>  drivers/crypto/ccp/dbc.c | 53 ++++++++++++++--------------------------
>  1 file changed, 19 insertions(+), 34 deletions(-)
> 
> diff --git a/drivers/crypto/ccp/dbc.c b/drivers/crypto/ccp/dbc.c
> index 5b105a23f6997..a3c6822b3829a 100644
> --- a/drivers/crypto/ccp/dbc.c
> +++ b/drivers/crypto/ccp/dbc.c
> @@ -7,6 +7,8 @@
>   * Author: Mario Limonciello <mario.limonciello@amd.com>
>   */
>  
> +#include <linux/mutex.h>
> +
>  #include "dbc.h"
>  
>  #define DBC_DEFAULT_TIMEOUT		(10 * MSEC_PER_SEC)
> @@ -137,64 +139,47 @@ 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;
> -
>  	}
> -unlock:
> -	mutex_unlock(&dbc_dev->ioctl_mutex);
>  
> -	return ret;
> +	return -EINVAL;

Hmmm... not quite what I said when I said to put a return -EINVAL in the
default case. You now return -EINVAL for every successful case.

Thanks,
Tom

>  }
>  
>  static const struct file_operations dbc_fops = {
diff mbox series

Patch

diff --git a/drivers/crypto/ccp/dbc.c b/drivers/crypto/ccp/dbc.c
index 5b105a23f6997..a3c6822b3829a 100644
--- a/drivers/crypto/ccp/dbc.c
+++ b/drivers/crypto/ccp/dbc.c
@@ -7,6 +7,8 @@ 
  * Author: Mario Limonciello <mario.limonciello@amd.com>
  */
 
+#include <linux/mutex.h>
+
 #include "dbc.h"
 
 #define DBC_DEFAULT_TIMEOUT		(10 * MSEC_PER_SEC)
@@ -137,64 +139,47 @@  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;
-
 	}
-unlock:
-	mutex_unlock(&dbc_dev->ioctl_mutex);
 
-	return ret;
+	return -EINVAL;
 }
 
 static const struct file_operations dbc_fops = {