From 9c96bacf1af51bc71898f31e025f08338c6ca4da Mon Sep 17 00:00:00 2001 From: Bjorn Andersson Date: Mon, 13 Feb 2023 07:52:14 -0800 Subject: 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 Signed-off-by: Bjorn Andersson Signed-off-by: Bjorn Andersson Link: https://lore.kernel.org/r/20230213155215.1237059-6-quic_bjorande@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 8dd8cf033b2d..946128c343f3 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); -- cgit v1.2.3