From: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Date: Tue, 20 Mar 2018 07:59:14 +0100
Subject: s390/qeth: lock read device while queueing next buffer
Git-commit: 17bf8c9b3d499d5168537c98b61eb7a1fcbca6c2
Patch-mainline: v4.16-rc7
References: networking-stable-18_03_28
For calling ccw_device_start(), issue_next_read() needs to hold the
device's ccwlock.
This is satisfied for the IRQ handler path (where qeth_irq() gets called
under the ccwlock), but we need explicit locking for the initial call by
the MPC initialization.
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/s390/net/qeth_core_main.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -526,8 +526,7 @@ static inline int qeth_is_cq(struct qeth
queue == card->qdio.no_in_queues - 1;
}
-
-static int qeth_issue_next_read(struct qeth_card *card)
+static int __qeth_issue_next_read(struct qeth_card *card)
{
int rc;
struct qeth_cmd_buffer *iob;
@@ -558,6 +557,17 @@ static int qeth_issue_next_read(struct q
return rc;
}
+static int qeth_issue_next_read(struct qeth_card *card)
+{
+ int ret;
+
+ spin_lock_irq(get_ccwdev_lock(CARD_RDEV(card)));
+ ret = __qeth_issue_next_read(card);
+ spin_unlock_irq(get_ccwdev_lock(CARD_RDEV(card)));
+
+ return ret;
+}
+
static struct qeth_reply *qeth_alloc_reply(struct qeth_card *card)
{
struct qeth_reply *reply;
@@ -1183,7 +1193,7 @@ static void qeth_irq(struct ccw_device *
return;
if (channel == &card->read &&
channel->state == CH_STATE_UP)
- qeth_issue_next_read(card);
+ __qeth_issue_next_read(card);
iob = channel->iob;
index = channel->buf_no;