[PATCH] talitos: allocate channels with main struct

[PATCH] talitos: allocate channels with main struct

[Rosen Penev]

Use a flexible array member to combine allocations.

Add __counted_by for extra runtime analysis.

Error in case of no channels as they are required.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 v2: error when no channels
 drivers/crypto/talitos.c | 19 +++++++------------
 drivers/crypto/talitos.h |  5 +++--
 2 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index bc61d0fe3514..bd4cc06ee13c 100644
--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -3409,14 +3409,20 @@ static int talitos_probe(struct platform_device *ofdev)
 	struct device *dev = &ofdev->dev;
 	struct device_node *np = ofdev->dev.of_node;
 	struct talitos_private *priv;
+	unsigned int num_channels;
 	int i, err;
 	int stride;
 	struct resource *res;
 
-	priv = devm_kzalloc(dev, sizeof(struct talitos_private), GFP_KERNEL);
+	if (of_property_read_u32(np, "fsl,num-channels", &num_channels))
+		return -EINVAL;
+
+	priv = devm_kzalloc(dev, struct_size(priv, chan, num_channels), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
+	priv->num_channels = num_channels;
+
 	INIT_LIST_HEAD(&priv->alg_list);
 
 	dev_set_drvdata(dev, priv);
@@ -3436,7 +3442,6 @@ static int talitos_probe(struct platform_device *ofdev)
 	}
 
 	/* get SEC version capabilities from device tree */
-	of_property_read_u32(np, "fsl,num-channels", &priv->num_channels);
 	of_property_read_u32(np, "fsl,channel-fifo-len", &priv->chfifo_len);
 	of_property_read_u32(np, "fsl,exec-units-mask", &priv->exec_units);
 	of_property_read_u32(np, "fsl,descriptor-types-mask",
@@ -3511,16 +3516,6 @@ static int talitos_probe(struct platform_device *ofdev)
 		}
 	}
 
-	priv->chan = devm_kcalloc(dev,
-				  priv->num_channels,
-				  sizeof(struct talitos_channel),
-				  GFP_KERNEL);
-	if (!priv->chan) {
-		dev_err(dev, "failed to allocate channel management space\n");
-		err = -ENOMEM;
-		goto err_out;
-	}
-
 	priv->fifo_len = roundup_pow_of_two(priv->chfifo_len);
 
 	for (i = 0; i < priv->num_channels; i++) {
diff --git a/drivers/crypto/talitos.h b/drivers/crypto/talitos.h
index 1a93ee355929..34b0b5fab7e7 100644
--- a/drivers/crypto/talitos.h
+++ b/drivers/crypto/talitos.h
@@ -139,8 +139,6 @@ struct talitos_private {
 	 */
 	unsigned int fifo_len;
 
-	struct talitos_channel *chan;
-
 	/* next channel to be assigned next incoming descriptor */
 	atomic_t last_chan ____cacheline_aligned;
 
@@ -153,6 +151,9 @@ struct talitos_private {
 	/* hwrng device */
 	struct hwrng rng;
 	bool rng_registered;
+
+	struct talitos_channel chan[] __counted_by(num_channels);
+
 };
 
 /* .features flag */
-- 
2.54.0

Re: [PATCH] talitos: allocate channels with main struct

[Paul Louvel]

On Wed May 6, 2026 at 10:56 AM CEST, Rosen Penev wrote:
> Use a flexible array member to combine allocations.
>
> Add __counted_by for extra runtime analysis.
>
> Error in case of no channels as they are required.
>
> Signed-off-by: Rosen Penev <rosenp@gmail.com>
> ---
>  v2: error when no channels
>  drivers/crypto/talitos.c | 19 +++++++------------
>  drivers/crypto/talitos.h |  5 +++--
>  2 files changed, 10 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
> index bc61d0fe3514..bd4cc06ee13c 100644
> --- a/drivers/crypto/talitos.c
> +++ b/drivers/crypto/talitos.c
> @@ -3409,14 +3409,20 @@ static int talitos_probe(struct platform_device *ofdev)
>  	struct device *dev = &ofdev->dev;
>  	struct device_node *np = ofdev->dev.of_node;
>  	struct talitos_private *priv;
> +	unsigned int num_channels;
>  	int i, err;
>  	int stride;
>  	struct resource *res;
>  
> -	priv = devm_kzalloc(dev, sizeof(struct talitos_private), GFP_KERNEL);
> +	if (of_property_read_u32(np, "fsl,num-channels", &num_channels))
> +		return -EINVAL;

Actually, this check does not guards against the num-channels property having a
value of 0 :
https://elixir.bootlin.com/linux/v7.0.1/source/include/linux/of.h#L1384
This check is done here :
https://elixir.bootlin.com/linux/v7.0.1/source/drivers/crypto/talitos.c#L3367
when checking the property data in the DT node. is_power_of_two does not
consider that 0 is a valid power of two.

Channels was not allocated because the DT node value was invalid. Ideally,
the driver should validate the DT node before requesting any resources, but this
is outside the scope of this patch.

-- 
Paul Louvel, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

[PATCH] talitos: allocate channels with main struct

[Rosen Penev]

Use a flexible array member to combine allocations.

Add __counted_by for extra runtime analysis.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/crypto/talitos.c | 17 +++++------------
 drivers/crypto/talitos.h |  5 +++--
 2 files changed, 8 insertions(+), 14 deletions(-)

diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index bc61d0fe3514..98323c154031 100644
--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -3409,14 +3409,18 @@ static int talitos_probe(struct platform_device *ofdev)
 	struct device *dev = &ofdev->dev;
 	struct device_node *np = ofdev->dev.of_node;
 	struct talitos_private *priv;
+	unsigned int num_channels;
 	int i, err;
 	int stride;
 	struct resource *res;
 
-	priv = devm_kzalloc(dev, sizeof(struct talitos_private), GFP_KERNEL);
+	of_property_read_u32(np, "fsl,num-channels", &num_channels);
+	priv = devm_kzalloc(dev, struct_size(priv, chan, num_channels), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
+	priv->num_channels = num_channels;
+
 	INIT_LIST_HEAD(&priv->alg_list);
 
 	dev_set_drvdata(dev, priv);
@@ -3436,7 +3440,6 @@ static int talitos_probe(struct platform_device *ofdev)
 	}
 
 	/* get SEC version capabilities from device tree */
-	of_property_read_u32(np, "fsl,num-channels", &priv->num_channels);
 	of_property_read_u32(np, "fsl,channel-fifo-len", &priv->chfifo_len);
 	of_property_read_u32(np, "fsl,exec-units-mask", &priv->exec_units);
 	of_property_read_u32(np, "fsl,descriptor-types-mask",
@@ -3511,16 +3514,6 @@ static int talitos_probe(struct platform_device *ofdev)
 		}
 	}
 
-	priv->chan = devm_kcalloc(dev,
-				  priv->num_channels,
-				  sizeof(struct talitos_channel),
-				  GFP_KERNEL);
-	if (!priv->chan) {
-		dev_err(dev, "failed to allocate channel management space\n");
-		err = -ENOMEM;
-		goto err_out;
-	}
-
 	priv->fifo_len = roundup_pow_of_two(priv->chfifo_len);
 
 	for (i = 0; i < priv->num_channels; i++) {
diff --git a/drivers/crypto/talitos.h b/drivers/crypto/talitos.h
index 1a93ee355929..34b0b5fab7e7 100644
--- a/drivers/crypto/talitos.h
+++ b/drivers/crypto/talitos.h
@@ -139,8 +139,6 @@ struct talitos_private {
 	 */
 	unsigned int fifo_len;
 
-	struct talitos_channel *chan;
-
 	/* next channel to be assigned next incoming descriptor */
 	atomic_t last_chan ____cacheline_aligned;
 
@@ -153,6 +151,9 @@ struct talitos_private {
 	/* hwrng device */
 	struct hwrng rng;
 	bool rng_registered;
+
+	struct talitos_channel chan[] __counted_by(num_channels);
+
 };
 
 /* .features flag */
-- 
2.54.0

Re: [PATCH] talitos: allocate channels with main struct

[Herbert Xu]

On Thu, Apr 30, 2026 at 02:43:40PM -0700, Rosen Penev wrote:
>
> -	priv = devm_kzalloc(dev, sizeof(struct talitos_private), GFP_KERNEL);
> +	of_property_read_u32(np, "fsl,num-channels", &num_channels);

Sashiko suggests that you check the return value of this call:

https://sashiko.dev/#/patchset/20260430214340.59588-1-rosenp%40gmail.com

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt