s390/qeth: lock read device while queueing next buffer

[ Upstream commit 17bf8c9b3d499d5168537c98b61eb7a1fcbca6c2 ]

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Julian Wiedmann 2018-03-20 07:59:14 +01:00 committed by Greg Kroah-Hartman
parent dd5ec73140
commit e524564220

View File

@ -526,8 +526,7 @@ static inline int qeth_is_cq(struct qeth_card *card, unsigned int queue)
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 qeth_card *card)
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 *cdev, unsigned long intparm,
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;