[v6,1/2] rpmsg: core: add API to get message length
diff mbox series

Message ID 1567602594-2913-2-git-send-email-arnaud.pouliquen@st.com
State New
Headers show
Series
  • TTY: add rpmsg tty driver
Related show

Commit Message

Arnaud Pouliquen Sept. 4, 2019, 1:09 p.m. UTC
Return the rpmsg buffer size for sending message, so rpmsg users
can split a long message in several sub rpmsg buffers.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
---
 drivers/rpmsg/rpmsg_core.c       | 21 +++++++++++++++++++++
 drivers/rpmsg/rpmsg_internal.h   |  2 ++
 drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++
 include/linux/rpmsg.h            | 10 ++++++++++
 4 files changed, 43 insertions(+)

Comments

Suman Anna Sept. 4, 2019, 4:36 p.m. UTC | #1
Hi Arnaud,

On 9/4/19 8:09 AM, Arnaud Pouliquen wrote:
> Return the rpmsg buffer size for sending message, so rpmsg users
> can split a long message in several sub rpmsg buffers.

Couple more minor comments..

> 
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
> ---
>  drivers/rpmsg/rpmsg_core.c       | 21 +++++++++++++++++++++
>  drivers/rpmsg/rpmsg_internal.h   |  2 ++
>  drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++
>  include/linux/rpmsg.h            | 10 ++++++++++
>  4 files changed, 43 insertions(+)
> 
> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
> index e330ec4dfc33..a6ef54c4779a 100644
> --- a/drivers/rpmsg/rpmsg_core.c
> +++ b/drivers/rpmsg/rpmsg_core.c
> @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
>  }
>  EXPORT_SYMBOL(rpmsg_trysend_offchannel);
>  
> +/**
> + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
> + * @ept: the rpmsg endpoint
> + *
> + * This function returns maximum buffer size available for a single message.
> + *
> + * Return: the maximum transmission size on success and an appropriate error
> + * value on failure.
> + */
> +
> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
> +{
> +	if (WARN_ON(!ept))
> +		return -EINVAL;
> +	if (!ept->ops->get_mtu)
> +		return -ENOTSUPP;
> +
> +	return ept->ops->get_mtu(ept);
> +}
> +EXPORT_SYMBOL(rpmsg_get_mtu);
> +
>  /*
>   * match an rpmsg channel with a channel info struct.
>   * this is used to make sure we're not creating rpmsg devices for channels
> diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
> index 3fc83cd50e98..12b9e72adc75 100644
> --- a/drivers/rpmsg/rpmsg_internal.h
> +++ b/drivers/rpmsg/rpmsg_internal.h
> @@ -47,6 +47,7 @@ struct rpmsg_device_ops {
>   * @trysendto:		see @rpmsg_trysendto(), optional
>   * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
>   * @poll:		see @rpmsg_poll(), optional
> + * @get_mtu:		see @get_mpu(), required

see @rpmsg_get_mtu(). Isn't this optional atm, since we haven't added
the callback for SMD transport?

>   *
>   * Indirection table for the operations that a rpmsg backend should implement.
>   * In addition to @destroy_ept, the backend must at least implement @send and
> @@ -66,6 +67,7 @@ struct rpmsg_endpoint_ops {
>  			     void *data, int len);
>  	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
>  			     poll_table *wait);
> +	ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
>  };
>  
>  int rpmsg_register_device(struct rpmsg_device *rpdev);
> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
> index 376ebbf880d6..fab01b67a550 100644
> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
> @@ -175,6 +175,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data,
>  				  int len, u32 dst);
>  static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
>  					   u32 dst, void *data, int len);
> +static ssize_t virtio_rpmsg_get_buf_mtu(struct rpmsg_endpoint *ept);
>  
>  static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
>  	.destroy_ept = virtio_rpmsg_destroy_ept,
> @@ -184,6 +185,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
>  	.trysend = virtio_rpmsg_trysend,
>  	.trysendto = virtio_rpmsg_trysendto,
>  	.trysend_offchannel = virtio_rpmsg_trysend_offchannel,
> +	.get_mtu = virtio_rpmsg_get_buf_mtu,
>  };
>  
>  /**
> @@ -699,6 +701,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
>  	return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false);
>  }
>  
> +static ssize_t virtio_rpmsg_get_buf_mtu(struct rpmsg_endpoint *ept)
> +{
> +	struct rpmsg_device *rpdev = ept->rpdev;
> +	struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev);
> +
> +	return vch->vrp->buf_size - sizeof(struct rpmsg_hdr);
> +}
> +
>  static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev,
>  			     struct rpmsg_hdr *msg, unsigned int len)
>  {
> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
> index 9fe156d1c018..9d638bf2bdce 100644
> --- a/include/linux/rpmsg.h
> +++ b/include/linux/rpmsg.h
> @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
>  __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
>  			poll_table *wait);
>  
> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
> +
>  #else
>  
>  static inline int register_rpmsg_device(struct rpmsg_device *dev)
> @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept,
>  	return 0;
>  }
>  
> +static ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)

static inline

regards
Suman

> +{
> +	/* This shouldn't be possible */
> +	WARN_ON(1);
> +
> +	return -ENXIO;
> +}
> +
>  #endif /* IS_ENABLED(CONFIG_RPMSG) */
>  
>  /* use a macro to avoid include chaining to get THIS_MODULE */
>
Arnaud Pouliquen Sept. 4, 2019, 5:30 p.m. UTC | #2
Hi Suman

On 9/4/19 6:36 PM, Suman Anna wrote:
> Hi Arnaud,
> 
> On 9/4/19 8:09 AM, Arnaud Pouliquen wrote:
>> Return the rpmsg buffer size for sending message, so rpmsg users
>> can split a long message in several sub rpmsg buffers.
> 
> Couple more minor comments..
> 
>>
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
>> ---
>>   drivers/rpmsg/rpmsg_core.c       | 21 +++++++++++++++++++++
>>   drivers/rpmsg/rpmsg_internal.h   |  2 ++
>>   drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++
>>   include/linux/rpmsg.h            | 10 ++++++++++
>>   4 files changed, 43 insertions(+)
>>
>> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
>> index e330ec4dfc33..a6ef54c4779a 100644
>> --- a/drivers/rpmsg/rpmsg_core.c
>> +++ b/drivers/rpmsg/rpmsg_core.c
>> @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
>>   }
>>   EXPORT_SYMBOL(rpmsg_trysend_offchannel);
>>   
>> +/**
>> + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
>> + * @ept: the rpmsg endpoint
>> + *
>> + * This function returns maximum buffer size available for a single message.
>> + *
>> + * Return: the maximum transmission size on success and an appropriate error
>> + * value on failure.
>> + */
>> +
>> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
>> +{
>> +	if (WARN_ON(!ept))
>> +		return -EINVAL;
>> +	if (!ept->ops->get_mtu)
>> +		return -ENOTSUPP;
>> +
>> +	return ept->ops->get_mtu(ept);
>> +}
>> +EXPORT_SYMBOL(rpmsg_get_mtu);
>> +
>>   /*
>>    * match an rpmsg channel with a channel info struct.
>>    * this is used to make sure we're not creating rpmsg devices for channels
>> diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
>> index 3fc83cd50e98..12b9e72adc75 100644
>> --- a/drivers/rpmsg/rpmsg_internal.h
>> +++ b/drivers/rpmsg/rpmsg_internal.h
>> @@ -47,6 +47,7 @@ struct rpmsg_device_ops {
>>    * @trysendto:		see @rpmsg_trysendto(), optional
>>    * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
>>    * @poll:		see @rpmsg_poll(), optional
>> + * @get_mtu:		see @get_mpu(), required
> 
> see @rpmsg_get_mtu(). Isn't this optional atm, since we haven't added
> the callback for SMD transport?

It is a good point.
On one side, if optional, rpmsg_get_mtu returns an error and the rpmsg 
client has to define a default value, but which one?
On the other, if required, i need to implement it for SMD and Glink 
driver. Calculate the mtu for these implementations does not seems 
trivial (if possible...). And i don't know how to test dev on these 
platforms.

Any suggestions?

Regards
Arnaud

> 
>>    *
>>    * Indirection table for the operations that a rpmsg backend should implement.
>>    * In addition to @destroy_ept, the backend must at least implement @send and
>> @@ -66,6 +67,7 @@ struct rpmsg_endpoint_ops {
>>   			     void *data, int len);
>>   	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
>>   			     poll_table *wait);
>> +	ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
>>   };
>>   
>>   int rpmsg_register_device(struct rpmsg_device *rpdev);
>> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
>> index 376ebbf880d6..fab01b67a550 100644
>> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
>> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
>> @@ -175,6 +175,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data,
>>   				  int len, u32 dst);
>>   static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
>>   					   u32 dst, void *data, int len);
>> +static ssize_t virtio_rpmsg_get_buf_mtu(struct rpmsg_endpoint *ept);
>>   
>>   static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
>>   	.destroy_ept = virtio_rpmsg_destroy_ept,
>> @@ -184,6 +185,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
>>   	.trysend = virtio_rpmsg_trysend,
>>   	.trysendto = virtio_rpmsg_trysendto,
>>   	.trysend_offchannel = virtio_rpmsg_trysend_offchannel,
>> +	.get_mtu = virtio_rpmsg_get_buf_mtu,
>>   };
>>   
>>   /**
>> @@ -699,6 +701,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
>>   	return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false);
>>   }
>>   
>> +static ssize_t virtio_rpmsg_get_buf_mtu(struct rpmsg_endpoint *ept)
>> +{
>> +	struct rpmsg_device *rpdev = ept->rpdev;
>> +	struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev);
>> +
>> +	return vch->vrp->buf_size - sizeof(struct rpmsg_hdr);
>> +}
>> +
>>   static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev,
>>   			     struct rpmsg_hdr *msg, unsigned int len)
>>   {
>> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
>> index 9fe156d1c018..9d638bf2bdce 100644
>> --- a/include/linux/rpmsg.h
>> +++ b/include/linux/rpmsg.h
>> @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
>>   __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
>>   			poll_table *wait);
>>   
>> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
>> +
>>   #else
>>   
>>   static inline int register_rpmsg_device(struct rpmsg_device *dev)
>> @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept,
>>   	return 0;
>>   }
>>   
>> +static ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
> 
> static inline
> 
> regards
> Suman
> 
>> +{
>> +	/* This shouldn't be possible */
>> +	WARN_ON(1);
>> +
>> +	return -ENXIO;
>> +}
>> +
>>   #endif /* IS_ENABLED(CONFIG_RPMSG) */
>>   
>>   /* use a macro to avoid include chaining to get THIS_MODULE */
>>
>

Patch
diff mbox series

diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index e330ec4dfc33..a6ef54c4779a 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -283,6 +283,27 @@  int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
 }
 EXPORT_SYMBOL(rpmsg_trysend_offchannel);
 
+/**
+ * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
+ * @ept: the rpmsg endpoint
+ *
+ * This function returns maximum buffer size available for a single message.
+ *
+ * Return: the maximum transmission size on success and an appropriate error
+ * value on failure.
+ */
+
+ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->get_mtu)
+		return -ENOTSUPP;
+
+	return ept->ops->get_mtu(ept);
+}
+EXPORT_SYMBOL(rpmsg_get_mtu);
+
 /*
  * match an rpmsg channel with a channel info struct.
  * this is used to make sure we're not creating rpmsg devices for channels
diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
index 3fc83cd50e98..12b9e72adc75 100644
--- a/drivers/rpmsg/rpmsg_internal.h
+++ b/drivers/rpmsg/rpmsg_internal.h
@@ -47,6 +47,7 @@  struct rpmsg_device_ops {
  * @trysendto:		see @rpmsg_trysendto(), optional
  * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
  * @poll:		see @rpmsg_poll(), optional
+ * @get_mtu:		see @get_mpu(), required
  *
  * Indirection table for the operations that a rpmsg backend should implement.
  * In addition to @destroy_ept, the backend must at least implement @send and
@@ -66,6 +67,7 @@  struct rpmsg_endpoint_ops {
 			     void *data, int len);
 	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
 			     poll_table *wait);
+	ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
 };
 
 int rpmsg_register_device(struct rpmsg_device *rpdev);
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 376ebbf880d6..fab01b67a550 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -175,6 +175,7 @@  static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data,
 				  int len, u32 dst);
 static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
 					   u32 dst, void *data, int len);
+static ssize_t virtio_rpmsg_get_buf_mtu(struct rpmsg_endpoint *ept);
 
 static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
 	.destroy_ept = virtio_rpmsg_destroy_ept,
@@ -184,6 +185,7 @@  static const struct rpmsg_endpoint_ops virtio_endpoint_ops = {
 	.trysend = virtio_rpmsg_trysend,
 	.trysendto = virtio_rpmsg_trysendto,
 	.trysend_offchannel = virtio_rpmsg_trysend_offchannel,
+	.get_mtu = virtio_rpmsg_get_buf_mtu,
 };
 
 /**
@@ -699,6 +701,14 @@  static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src,
 	return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false);
 }
 
+static ssize_t virtio_rpmsg_get_buf_mtu(struct rpmsg_endpoint *ept)
+{
+	struct rpmsg_device *rpdev = ept->rpdev;
+	struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev);
+
+	return vch->vrp->buf_size - sizeof(struct rpmsg_hdr);
+}
+
 static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev,
 			     struct rpmsg_hdr *msg, unsigned int len)
 {
diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
index 9fe156d1c018..9d638bf2bdce 100644
--- a/include/linux/rpmsg.h
+++ b/include/linux/rpmsg.h
@@ -135,6 +135,8 @@  int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
 __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
 			poll_table *wait);
 
+ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
+
 #else
 
 static inline int register_rpmsg_device(struct rpmsg_device *dev)
@@ -242,6 +244,14 @@  static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept,
 	return 0;
 }
 
+static ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
 #endif /* IS_ENABLED(CONFIG_RPMSG) */
 
 /* use a macro to avoid include chaining to get THIS_MODULE */