diff mbox series

[V8,3/3] rpmsg: char: Add RPMSG GET/SET FLOWCONTROL IOCTL support

Message ID 1687361648-27688-4-git-send-email-quic_sarannya@quicinc.com (mailing list archive)
State Superseded
Headers show
Series *** rpmsg signaling/flowcontrol patches *** | expand

Commit Message

Sarannya S June 21, 2023, 3:34 p.m. UTC 
From: Chris Lew <quic_clew@quicinc.com>

Add RPMSG_GET_OUTGOING_FLOWCONTROL and RPMSG_SET_INCOMING_FLOWCONTROL
IOCTL support for rpmsg char device nodes to get/set the low level
transport signals.

Signed-off-by: Chris Lew <quic_clew@quicinc.com>
Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
---
 drivers/rpmsg/rpmsg_char.c | 50 ++++++++++++++++++++++++++++++++++++++++------
 include/uapi/linux/rpmsg.h | 10 ++++++++++
 2 files changed, 54 insertions(+), 6 deletions(-)

Comments

Arnaud POULIQUEN June 23, 2023, 9:11 a.m. UTC | #1 
On 6/21/23 17:34, Sarannya S wrote:
> From: Chris Lew <quic_clew@quicinc.com>
> 
> Add RPMSG_GET_OUTGOING_FLOWCONTROL and RPMSG_SET_INCOMING_FLOWCONTROL
> IOCTL support for rpmsg char device nodes to get/set the low level
> transport signals.
> 
> Signed-off-by: Chris Lew <quic_clew@quicinc.com>
> Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
> Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
> ---
>  drivers/rpmsg/rpmsg_char.c | 50 ++++++++++++++++++++++++++++++++++++++++------
>  include/uapi/linux/rpmsg.h | 10 ++++++++++
>  2 files changed, 54 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
> index a271fce..2cdd31e 100644
> --- a/drivers/rpmsg/rpmsg_char.c
> +++ b/drivers/rpmsg/rpmsg_char.c
> @@ -52,6 +52,8 @@ static DEFINE_IDA(rpmsg_minor_ida);
>   * @readq:	wait object for incoming queue
>   * @default_ept: set to channel default endpoint if the default endpoint should be re-used
>   *              on device open to prevent endpoint address update.
> + * remote_flow_restricted: to indicate if the remote has requested for flow to be limited
> + * remote_flow_updated:	to indicate if the flow control has been requested

replace tab by space after ':'

>   */
>  struct rpmsg_eptdev {
>  	struct device dev;
> @@ -68,6 +70,8 @@ struct rpmsg_eptdev {
>  	struct sk_buff_head queue;
>  	wait_queue_head_t readq;
>  
> +	bool remote_flow_restricted;
> +	bool remote_flow_updated;
>  };
>  
>  int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data)
> @@ -116,6 +120,18 @@ static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len,
>  	return 0;
>  }
>  
> +static int rpmsg_ept_flow_cb(struct rpmsg_device *rpdev, void *priv, bool enable)
> +{
> +	struct rpmsg_eptdev *eptdev = priv;
> +
> +	eptdev->remote_flow_restricted = enable;
> +	eptdev->remote_flow_updated = true;
> +
> +	wake_up_interruptible(&eptdev->readq);
> +
> +	return 0;
> +}
> +
>  static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
>  {
>  	struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
> @@ -152,6 +168,7 @@ static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
>  		return -EINVAL;
>  	}
>  
> +	ept->flow_cb = rpmsg_ept_flow_cb;
>  	eptdev->ept = ept;
>  	filp->private_data = eptdev;
>  	mutex_unlock(&eptdev->ept_lock);
> @@ -172,6 +189,7 @@ static int rpmsg_eptdev_release(struct inode *inode, struct file *filp)
>  		eptdev->ept = NULL;
>  	}
>  	mutex_unlock(&eptdev->ept_lock);
> +	eptdev->remote_flow_updated = false;
>  
>  	/* Discard all SKBs */
>  	skb_queue_purge(&eptdev->queue);
> @@ -285,6 +303,9 @@ static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
>  	if (!skb_queue_empty(&eptdev->queue))
>  		mask |= EPOLLIN | EPOLLRDNORM;
>  
> +	if (eptdev->remote_flow_updated)
> +		mask |= EPOLLPRI;
> +
>  	mutex_lock(&eptdev->ept_lock);
>  	mask |= rpmsg_poll(eptdev->ept, filp, wait);
>  	mutex_unlock(&eptdev->ept_lock);
> @@ -297,14 +318,31 @@ static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
>  {
>  	struct rpmsg_eptdev *eptdev = fp->private_data;
>  
> -	if (cmd != RPMSG_DESTROY_EPT_IOCTL)
> -		return -EINVAL;
> +	bool set;
> +	int ret;
>  
> -	/* Don't allow to destroy a default endpoint. */
> -	if (eptdev->default_ept)
> -		return -EINVAL;
> +	switch (cmd) {
> +	case RPMSG_GET_OUTGOING_FLOWCONTROL:
> +		eptdev->remote_flow_updated = false;
> +		ret = put_user(eptdev->remote_flow_restricted, (int __user *)arg);
> +		break;
> +	case RPMSG_SET_INCOMING_FLOWCONTROL:
> +		set = !!arg;
> +		ret = rpmsg_set_flow_control(eptdev->ept, set, eptdev->chinfo.dst);
> +		break;
> +	case RPMSG_DESTROY_EPT_IOCTL:
> +		/* Don't allow to destroy a default endpoint. */
> +		if (eptdev->default_ept) {
> +			ret = -EINVAL;
> +			break;
> +		}
> +		ret = rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
>  
> -	return rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
> +	return ret;
>  }
>  
>  static const struct file_operations rpmsg_eptdev_fops = {
> diff --git a/include/uapi/linux/rpmsg.h b/include/uapi/linux/rpmsg.h
> index 1637e68..b0a6c17 100644
> --- a/include/uapi/linux/rpmsg.h
> +++ b/include/uapi/linux/rpmsg.h
> @@ -43,4 +43,14 @@ struct rpmsg_endpoint_info {
>   */
>  #define RPMSG_RELEASE_DEV_IOCTL	_IOW(0xb5, 0x4, struct rpmsg_endpoint_info)
>  
> +/**
> + * Set the flow control for the remote rpmsg char device.
> + */
> +#define RPMSG_GET_OUTGOING_FLOWCONTROL _IOW(0xb5, 0x5, struct rpmsg_endpoint_info)
> +
> +/**
> + * Set the flow control for the local rpmsg char device.
> + */
> +#define RPMSG_SET_INCOMING_FLOWCONTROL _IOW(0xb5, 0x6, struct rpmsg_endpoint_info)


Perhaps I missed something, but you use "rpmsg_endpoint_info" as argument.
In rpmsg_eptdev_ioctl the argument is treated as a boolean.
Seems to me that something is wrong here.

regards,
Arnaud

> +
>  #endif
Bjorn Andersson July 6, 2023, 2:57 a.m. UTC | #2 
On Fri, Jun 23, 2023 at 11:11:03AM +0200, Arnaud POULIQUEN wrote:
> On 6/21/23 17:34, Sarannya S wrote:
[..]
> > diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
[..]
> > +	switch (cmd) {
> > +	case RPMSG_GET_OUTGOING_FLOWCONTROL:
> > +		eptdev->remote_flow_updated = false;
> > +		ret = put_user(eptdev->remote_flow_restricted, (int __user *)arg);
> > +		break;
> > +	case RPMSG_SET_INCOMING_FLOWCONTROL:
> > +		set = !!arg;
> > +		ret = rpmsg_set_flow_control(eptdev->ept, set, eptdev->chinfo.dst);
> > +		break;
> > +	case RPMSG_DESTROY_EPT_IOCTL:
> > +		/* Don't allow to destroy a default endpoint. */
> > +		if (eptdev->default_ept) {
> > +			ret = -EINVAL;
> > +			break;
> > +		}
> > +		ret = rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
> > +		break;
> > +	default:
> > +		ret = -EINVAL;
> > +	}
> >  
> > -	return rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
> > +	return ret;
> >  }
> >  
> >  static const struct file_operations rpmsg_eptdev_fops = {
> > diff --git a/include/uapi/linux/rpmsg.h b/include/uapi/linux/rpmsg.h
> > index 1637e68..b0a6c17 100644
> > --- a/include/uapi/linux/rpmsg.h
> > +++ b/include/uapi/linux/rpmsg.h
> > @@ -43,4 +43,14 @@ struct rpmsg_endpoint_info {
> >   */
> >  #define RPMSG_RELEASE_DEV_IOCTL	_IOW(0xb5, 0x4, struct rpmsg_endpoint_info)
> >  
> > +/**
> > + * Set the flow control for the remote rpmsg char device.

We improved the wording elsewhere in the patch, to make the description
of what the interface controls/exposes. This would benefit from the same
attention.

And this says "Set" while the ioctl says "GET".

> > + */
> > +#define RPMSG_GET_OUTGOING_FLOWCONTROL _IOW(0xb5, 0x5, struct rpmsg_endpoint_info)
> > +
> > +/**
> > + * Set the flow control for the local rpmsg char device.
> > + */
> > +#define RPMSG_SET_INCOMING_FLOWCONTROL _IOW(0xb5, 0x6, struct rpmsg_endpoint_info)
> 
> 
> Perhaps I missed something, but you use "rpmsg_endpoint_info" as argument.
> In rpmsg_eptdev_ioctl the argument is treated as a boolean.
> Seems to me that something is wrong here.
> 

This is indeed an int in the implementation above.

Regards,
Bjorn

> regards,
> Arnaud
> 
> > +
> >  #endif
diff mbox series

Patch

diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
index a271fce..2cdd31e 100644
--- a/drivers/rpmsg/rpmsg_char.c
+++ b/drivers/rpmsg/rpmsg_char.c
@@ -52,6 +52,8 @@  static DEFINE_IDA(rpmsg_minor_ida);
  * @readq:	wait object for incoming queue
  * @default_ept: set to channel default endpoint if the default endpoint should be re-used
  *              on device open to prevent endpoint address update.
+ * remote_flow_restricted: to indicate if the remote has requested for flow to be limited
+ * remote_flow_updated:	to indicate if the flow control has been requested
  */
 struct rpmsg_eptdev {
 	struct device dev;
@@ -68,6 +70,8 @@  struct rpmsg_eptdev {
 	struct sk_buff_head queue;
 	wait_queue_head_t readq;
 
+	bool remote_flow_restricted;
+	bool remote_flow_updated;
 };
 
 int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data)
@@ -116,6 +120,18 @@  static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len,
 	return 0;
 }
 
+static int rpmsg_ept_flow_cb(struct rpmsg_device *rpdev, void *priv, bool enable)
+{
+	struct rpmsg_eptdev *eptdev = priv;
+
+	eptdev->remote_flow_restricted = enable;
+	eptdev->remote_flow_updated = true;
+
+	wake_up_interruptible(&eptdev->readq);
+
+	return 0;
+}
+
 static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
 {
 	struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
@@ -152,6 +168,7 @@  static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
 		return -EINVAL;
 	}
 
+	ept->flow_cb = rpmsg_ept_flow_cb;
 	eptdev->ept = ept;
 	filp->private_data = eptdev;
 	mutex_unlock(&eptdev->ept_lock);
@@ -172,6 +189,7 @@  static int rpmsg_eptdev_release(struct inode *inode, struct file *filp)
 		eptdev->ept = NULL;
 	}
 	mutex_unlock(&eptdev->ept_lock);
+	eptdev->remote_flow_updated = false;
 
 	/* Discard all SKBs */
 	skb_queue_purge(&eptdev->queue);
@@ -285,6 +303,9 @@  static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
 	if (!skb_queue_empty(&eptdev->queue))
 		mask |= EPOLLIN | EPOLLRDNORM;
 
+	if (eptdev->remote_flow_updated)
+		mask |= EPOLLPRI;
+
 	mutex_lock(&eptdev->ept_lock);
 	mask |= rpmsg_poll(eptdev->ept, filp, wait);
 	mutex_unlock(&eptdev->ept_lock);
@@ -297,14 +318,31 @@  static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
 {
 	struct rpmsg_eptdev *eptdev = fp->private_data;
 
-	if (cmd != RPMSG_DESTROY_EPT_IOCTL)
-		return -EINVAL;
+	bool set;
+	int ret;
 
-	/* Don't allow to destroy a default endpoint. */
-	if (eptdev->default_ept)
-		return -EINVAL;
+	switch (cmd) {
+	case RPMSG_GET_OUTGOING_FLOWCONTROL:
+		eptdev->remote_flow_updated = false;
+		ret = put_user(eptdev->remote_flow_restricted, (int __user *)arg);
+		break;
+	case RPMSG_SET_INCOMING_FLOWCONTROL:
+		set = !!arg;
+		ret = rpmsg_set_flow_control(eptdev->ept, set, eptdev->chinfo.dst);
+		break;
+	case RPMSG_DESTROY_EPT_IOCTL:
+		/* Don't allow to destroy a default endpoint. */
+		if (eptdev->default_ept) {
+			ret = -EINVAL;
+			break;
+		}
+		ret = rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
+		break;
+	default:
+		ret = -EINVAL;
+	}
 
-	return rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
+	return ret;
 }
 
 static const struct file_operations rpmsg_eptdev_fops = {
diff --git a/include/uapi/linux/rpmsg.h b/include/uapi/linux/rpmsg.h
index 1637e68..b0a6c17 100644
--- a/include/uapi/linux/rpmsg.h
+++ b/include/uapi/linux/rpmsg.h
@@ -43,4 +43,14 @@  struct rpmsg_endpoint_info {
  */
 #define RPMSG_RELEASE_DEV_IOCTL	_IOW(0xb5, 0x4, struct rpmsg_endpoint_info)
 
+/**
+ * Set the flow control for the remote rpmsg char device.
+ */
+#define RPMSG_GET_OUTGOING_FLOWCONTROL _IOW(0xb5, 0x5, struct rpmsg_endpoint_info)
+
+/**
+ * Set the flow control for the local rpmsg char device.
+ */
+#define RPMSG_SET_INCOMING_FLOWCONTROL _IOW(0xb5, 0x6, struct rpmsg_endpoint_info)
+
 #endif