From e8f206cc602021f0e70c5d12f16344ef0190fcc8 Mon Sep 17 00:00:00 2001
From: Hans Petter Selasky <hselasky@FreeBSD.org>
Date: Wed, 2 Oct 2019 09:03:48 +0000
Subject: [PATCH] Notify all sleeping threads of device removal in krping.
 Implement d_purge for krping_cdevsw.

Submitted by:	slavash@
MFC after:	3 days
Sponsored by:	Mellanox Technologies
---
 sys/contrib/rdma/krping/krping.c     | 14 ++++++++++++++
 sys/contrib/rdma/krping/krping.h     |  1 +
 sys/contrib/rdma/krping/krping_dev.c |  9 +++++++++
 3 files changed, 24 insertions(+)

diff --git a/sys/contrib/rdma/krping/krping.c b/sys/contrib/rdma/krping/krping.c
index 7b1038c27db7..8b32fe31f4cb 100644
--- a/sys/contrib/rdma/krping/krping.c
+++ b/sys/contrib/rdma/krping/krping.c
@@ -2189,3 +2189,17 @@ krping_walk_cb_list(void (*f)(struct krping_stats *, void *), void *arg)
 	    (*f)(cb->pd ? &cb->stats : NULL, arg);
 	mutex_unlock(&krping_mutex);
 }
+
+void
+krping_cancel_all(void)
+{
+	struct krping_cb *cb;
+
+	mutex_lock(&krping_mutex);
+	list_for_each_entry(cb, &krping_cbs, list) {
+		cb->state = ERROR;
+		wake_up_interruptible(&cb->sem);
+	}
+	mutex_unlock(&krping_mutex);
+}
+
diff --git a/sys/contrib/rdma/krping/krping.h b/sys/contrib/rdma/krping/krping.h
index 5987b1c8625f..37df45b86776 100644
--- a/sys/contrib/rdma/krping/krping.h
+++ b/sys/contrib/rdma/krping/krping.h
@@ -17,3 +17,4 @@ struct krping_stats {
 int krping_doit(char *);
 void krping_walk_cb_list(void (*)(struct krping_stats *, void *), void *);
 int krping_sigpending(void);
+void krping_cancel_all(void);
diff --git a/sys/contrib/rdma/krping/krping_dev.c b/sys/contrib/rdma/krping/krping_dev.c
index 342c5b0065f3..dda81af8c140 100644
--- a/sys/contrib/rdma/krping/krping_dev.c
+++ b/sys/contrib/rdma/krping/krping_dev.c
@@ -40,6 +40,7 @@ static d_open_t      krping_open;
 static d_close_t     krping_close;
 static d_read_t      krping_read;
 static d_write_t     krping_write;
+static d_purge_t     krping_purge;
 
 /* Character device entry points */
 static struct cdevsw krping_cdevsw = {
@@ -48,6 +49,7 @@ static struct cdevsw krping_cdevsw = {
 	.d_close = krping_close,
 	.d_read = krping_read,
 	.d_write = krping_write,
+	.d_purge = krping_purge,
 	.d_name = "krping",
 };
 
@@ -210,6 +212,13 @@ done:
 	return(err);
 }
 
+static void
+krping_purge(struct cdev *dev __unused)
+{
+
+	krping_cancel_all();
+}
+
 int
 krping_sigpending(void)
 {