[PATCH AUTOSEL 4.19 001/191] s390/qeth: uninstall IRQ handler on device removal

Sasha Levin
2019-11-10T02:40:20Z

From: Julian Wiedmann <jwi@linux.ibm.com>

[ Upstream commit 121ca39aa5585def682a2c8592983442438b84dc ]

When setting up, qeth installs its IRQ handler on the ccw devices. But
the IRQ handler is not cleared on removal - so even after qeth yields
control of the ccw devices, spurious interrupts would still be presented
to us.

Make (de-)installation of the IRQ handler part of the ccw channel
setup/removal helpers, and while at it also add the appropriate locking.
Shift around qeth_setup_channel() to avoid a forward declaration for
qeth_irq().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/s390/net/qeth_core_main.c | 102 ++++++++++++++++--------------
1 file changed, 54 insertions(+), 48 deletions(-)

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 461afc276db72..81e2c591acb0b 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -901,44 +901,6 @@ static void qeth_send_control_data_cb(struct qeth_channel *channel,
qeth_release_buffer(channel, iob);
}

-static int qeth_setup_channel(struct qeth_channel *channel, bool alloc_buffers)
-{
- int cnt;
-
- QETH_DBF_TEXT(SETUP, 2, "setupch");
-
- channel->ccw = kmalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
- if (!channel->ccw)
- return -ENOMEM;
- channel->state = CH_STATE_DOWN;
- atomic_set(&channel->irq_pending, 0);
- init_waitqueue_head(&channel->wait_q);
-
- if (!alloc_buffers)
- return 0;
-
- for (cnt = 0; cnt < QETH_CMD_BUFFER_NO; cnt++) {
- channel->iob[cnt].data =
- kzalloc(QETH_BUFSIZE, GFP_DMA|GFP_KERNEL);
- if (channel->iob[cnt].data == NULL)
- break;
- channel->iob[cnt].state = BUF_STATE_FREE;
- channel->iob[cnt].channel = channel;
- channel->iob[cnt].callback = qeth_send_control_data_cb;
- channel->iob[cnt].rc = 0;
- }
- if (cnt < QETH_CMD_BUFFER_NO) {
- kfree(channel->ccw);
- while (cnt-- > 0)
- kfree(channel->iob[cnt].data);
- return -ENOMEM;
- }
- channel->io_buf_no = 0;
- spin_lock_init(&channel->iob_lock);
-
- return 0;
-}
-
static int qeth_set_thread_start_bit(struct qeth_card *card,
unsigned long thread)
{
@@ -1339,14 +1301,61 @@ static void qeth_free_buffer_pool(struct qeth_card *card)

static void qeth_clean_channel(struct qeth_channel *channel)
{
+ struct ccw_device *cdev = channel->ccwdev;
int cnt;

QETH_DBF_TEXT(SETUP, 2, "freech");
+
+ spin_lock_irq(get_ccwdev_lock(cdev));
+ cdev->handler = NULL;
+ spin_unlock_irq(get_ccwdev_lock(cdev));
+
for (cnt = 0; cnt < QETH_CMD_BUFFER_NO; cnt++)
kfree(channel->iob[cnt].data);
kfree(channel->ccw);
}

+static int qeth_setup_channel(struct qeth_channel *channel, bool alloc_buffers)
+{
+ struct ccw_device *cdev = channel->ccwdev;
+ int cnt;
+
+ QETH_DBF_TEXT(SETUP, 2, "setupch");
+
+ channel->ccw = kmalloc(sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
+ if (!channel->ccw)
+ return -ENOMEM;
+ channel->state = CH_STATE_DOWN;
+ atomic_set(&channel->irq_pending, 0);
+ init_waitqueue_head(&channel->wait_q);
+
+ spin_lock_irq(get_ccwdev_lock(cdev));
+ cdev->handler = qeth_irq;
+ spin_unlock_irq(get_ccwdev_lock(cdev));
+
+ if (!alloc_buffers)
+ return 0;
+
+ for (cnt = 0; cnt < QETH_CMD_BUFFER_NO; cnt++) {
+ channel->iob[cnt].data =
+ kzalloc(QETH_BUFSIZE, GFP_DMA|GFP_KERNEL);
+ if (channel->iob[cnt].data == NULL)
+ break;
+ channel->iob[cnt].state = BUF_STATE_FREE;
+ channel->iob[cnt].channel = channel;
+ channel->iob[cnt].callback = qeth_send_control_data_cb;
+ channel->iob[cnt].rc = 0;
+ }
+ if (cnt < QETH_CMD_BUFFER_NO) {
+ qeth_clean_channel(channel);
+ return -ENOMEM;
+ }
+ channel->io_buf_no = 0;
+ spin_lock_init(&channel->iob_lock);
+
+ return 0;
+}
+
static void qeth_set_single_write_queues(struct qeth_card *card)
{
if ((atomic_read(&card->qdio.state) != QETH_QDIO_UNINITIALIZED) &&
@@ -1498,7 +1507,7 @@ static void qeth_core_sl_print(struct seq_file *m, struct service_level *slr)
CARD_BUS_ID(card), card->info.mcl_level);
}

-static struct qeth_card *qeth_alloc_card(void)
+static struct qeth_card *qeth_alloc_card(struct ccwgroup_device *gdev)
{
struct qeth_card *card;

@@ -1507,6 +1516,11 @@ static struct qeth_card *qeth_alloc_card(void)
if (!card)
goto out;
QETH_DBF_HEX(SETUP, 2, &card, sizeof(void *));
+
+ card->gdev = gdev;
+ CARD_RDEV(card) = gdev->cdev[0];
+ CARD_WDEV(card) = gdev->cdev[1];
+ CARD_DDEV(card) = gdev->cdev[2];
if (qeth_setup_channel(&card->read, true))
goto out_ip;
if (qeth_setup_channel(&card->write, true))
@@ -5745,7 +5759,7 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)

QETH_DBF_TEXT_(SETUP, 2, "%s", dev_name(&gdev->dev));

- card = qeth_alloc_card();
+ card = qeth_alloc_card(gdev);
if (!card) {
QETH_DBF_TEXT_(SETUP, 2, "1err%d", -ENOMEM);
rc = -ENOMEM;
@@ -5761,15 +5775,7 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
goto err_card;
}

- card->read.ccwdev = gdev->cdev[0];
- card->write.ccwdev = gdev->cdev[1];
- card->data.ccwdev = gdev->cdev[2];
dev_set_drvdata(&gdev->dev, card);
- card->gdev = gdev;
- gdev->cdev[0]->handler = qeth_irq;
- gdev->cdev[1]->handler = qeth_irq;
- gdev->cdev[2]->handler = qeth_irq;
-
qeth_setup_card(card);
rc = qeth_update_from_chp_desc(card);
if (rc)
--
2.20.1