rpmsg: glink: Fail qcom_glink_tx() once remove has been initiated

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.

Reviewed-by: Chris Lew <quic_clew@quicinc.com>
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230213155215.1237059-6-quic_bjorande@quicinc.com
This commit is contained in:
Bjorn Andersson 2023-02-13 07:52:14 -08:00 committed by Bjorn Andersson
parent f424d1cbe8
commit 9c96bacf1a

View File

@ -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);