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[5/6] rpmsg: glink: Fail qcom_glink_tx() once remove has been initiated

Message ID 20230109224001.1706516-6-quic_bjorande@quicinc.com (mailing list archive)
State Superseded
Headers show
Series rpmsg: glink: Misc improvements | expand

Commit Message

Bjorn Andersson Jan. 9, 2023, 10:40 p.m. UTC
Upon removing the glink edge communication is at best one-way. This
means that the very common scenario of glink requesting intents will not
be possible to serve.

Typically a successful transmission results in the client waiting for a
response, with some timeout and a mechanism for aborting that timeout.

Because of this, once the glink edge is defunct once removal is
commenced it's better to fail transmissions fast.

Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
---
 drivers/rpmsg/qcom_glink_native.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

Comments

Chris Lew Jan. 25, 2023, 7:04 a.m. UTC | #1
On 1/9/2023 2:40 PM, Bjorn Andersson wrote:
> Upon removing the glink edge communication is at best one-way. This

glink edge, communication

> means that the very common scenario of glink requesting intents will not
> be possible to serve.
> 
> Typically a successful transmission results in the client waiting for a
> response, with some timeout and a mechanism for aborting that timeout.
> 
> Because of this, once the glink edge is defunct once removal is
> commenced it's better to fail transmissions fast.
> 
> Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
> ---

Reviewed-by: Chris Lew <quic_clew@quicinc.com>

>   drivers/rpmsg/qcom_glink_native.c | 20 ++++++++++++++++++++
>   1 file changed, 20 insertions(+)
> 
> diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
> index db5d946d5901..d81d0729493e 100644
> --- a/drivers/rpmsg/qcom_glink_native.c
> +++ b/drivers/rpmsg/qcom_glink_native.c
> @@ -90,6 +90,7 @@ struct glink_core_rx_intent {
>    * @intentless:	flag to indicate that there is no intent
>    * @tx_avail_notify: Waitqueue for pending tx tasks
>    * @sent_read_notify: flag to check cmd sent or not
> + * @abort_tx:	flag indicating that all tx attempts should fail
>    */
>   struct qcom_glink {
>   	struct device *dev;
> @@ -111,6 +112,8 @@ struct qcom_glink {
>   	bool intentless;
>   	wait_queue_head_t tx_avail_notify;
>   	bool sent_read_notify;
> +
> +	bool abort_tx;
>   };
>   
>   enum {
> @@ -326,12 +329,22 @@ static int qcom_glink_tx(struct qcom_glink *glink,
>   
>   	spin_lock_irqsave(&glink->tx_lock, flags);
>   
> +	if (glink->abort_tx) {
> +		ret = -EIO;
> +		goto out;
> +	}
> +
>   	while (qcom_glink_tx_avail(glink) < tlen) {
>   		if (!wait) {
>   			ret = -EAGAIN;
>   			goto out;
>   		}
>   
> +		if (glink->abort_tx) {
> +			ret = -EIO;
> +			goto out;
> +		}
> +
>   		if (!glink->sent_read_notify) {
>   			glink->sent_read_notify = true;
>   			qcom_glink_send_read_notify(glink);
> @@ -1763,11 +1776,18 @@ static int qcom_glink_remove_device(struct device *dev, void *data)
>   void qcom_glink_native_remove(struct qcom_glink *glink)
>   {
>   	struct glink_channel *channel;
> +	unsigned long flags;
>   	int cid;
>   	int ret;
>   
>   	qcom_glink_cancel_rx_work(glink);
>   
> +	/* Fail all attempts at sending messages */
> +	spin_lock_irqsave(&glink->tx_lock, flags);
> +	glink->abort_tx = true;
> +	wake_up_all(&glink->tx_avail_notify);
> +	spin_unlock_irqrestore(&glink->tx_lock, flags);
> +
>   	ret = device_for_each_child(glink->dev, NULL, qcom_glink_remove_device);
>   	if (ret)
>   		dev_warn(glink->dev, "Can't remove GLINK devices: %d\n", ret);
diff mbox series

Patch

diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
index db5d946d5901..d81d0729493e 100644
--- a/drivers/rpmsg/qcom_glink_native.c
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -90,6 +90,7 @@  struct glink_core_rx_intent {
  * @intentless:	flag to indicate that there is no intent
  * @tx_avail_notify: Waitqueue for pending tx tasks
  * @sent_read_notify: flag to check cmd sent or not
+ * @abort_tx:	flag indicating that all tx attempts should fail
  */
 struct qcom_glink {
 	struct device *dev;
@@ -111,6 +112,8 @@  struct qcom_glink {
 	bool intentless;
 	wait_queue_head_t tx_avail_notify;
 	bool sent_read_notify;
+
+	bool abort_tx;
 };
 
 enum {
@@ -326,12 +329,22 @@  static int qcom_glink_tx(struct qcom_glink *glink,
 
 	spin_lock_irqsave(&glink->tx_lock, flags);
 
+	if (glink->abort_tx) {
+		ret = -EIO;
+		goto out;
+	}
+
 	while (qcom_glink_tx_avail(glink) < tlen) {
 		if (!wait) {
 			ret = -EAGAIN;
 			goto out;
 		}
 
+		if (glink->abort_tx) {
+			ret = -EIO;
+			goto out;
+		}
+
 		if (!glink->sent_read_notify) {
 			glink->sent_read_notify = true;
 			qcom_glink_send_read_notify(glink);
@@ -1763,11 +1776,18 @@  static int qcom_glink_remove_device(struct device *dev, void *data)
 void qcom_glink_native_remove(struct qcom_glink *glink)
 {
 	struct glink_channel *channel;
+	unsigned long flags;
 	int cid;
 	int ret;
 
 	qcom_glink_cancel_rx_work(glink);
 
+	/* Fail all attempts at sending messages */
+	spin_lock_irqsave(&glink->tx_lock, flags);
+	glink->abort_tx = true;
+	wake_up_all(&glink->tx_avail_notify);
+	spin_unlock_irqrestore(&glink->tx_lock, flags);
+
 	ret = device_for_each_child(glink->dev, NULL, qcom_glink_remove_device);
 	if (ret)
 		dev_warn(glink->dev, "Can't remove GLINK devices: %d\n", ret);