[PATCH v6 01/10] s390: vfio-ap: Refactor vfio_ap driver probe and remove callbacks

From: Tony Krowiak
Date: Fri Sep 13 2019 - 17:27:14 EST


In order to limit the number of private mdev functions called from the
vfio_ap device driver as well as to provide a landing spot for dynamic
configuration code related to binding/unbinding AP queue devices to/from
the vfio_ap driver, the following changes are being introduced:

* Move code from the vfio_ap driver's probe callback into a function
defined in the mdev private operations file.

* Move code from the vfio_ap driver's remove callback into a function
defined in the mdev private operations file.

Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
---
drivers/s390/crypto/vfio_ap_drv.c | 23 +++--------
drivers/s390/crypto/vfio_ap_ops.c | 74 ++++++++++++++++++++++++++++++-----
drivers/s390/crypto/vfio_ap_private.h | 6 +--
3 files changed, 72 insertions(+), 31 deletions(-)

diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c
index 003662aa8060..9e61d4c6e6b5 100644
--- a/drivers/s390/crypto/vfio_ap_drv.c
+++ b/drivers/s390/crypto/vfio_ap_drv.c
@@ -49,15 +49,9 @@ MODULE_DEVICE_TABLE(vfio_ap, ap_queue_ids);
*/
static int vfio_ap_queue_dev_probe(struct ap_device *apdev)
{
- struct vfio_ap_queue *q;
-
- q = kzalloc(sizeof(*q), GFP_KERNEL);
- if (!q)
- return -ENOMEM;
- dev_set_drvdata(&apdev->device, q);
- q->apqn = to_ap_queue(&apdev->device)->qid;
- q->saved_isc = VFIO_AP_ISC_INVALID;
- return 0;
+ struct ap_queue *queue = to_ap_queue(&apdev->device);
+
+ return vfio_ap_mdev_probe_queue(queue);
}

/**
@@ -68,17 +62,10 @@ static int vfio_ap_queue_dev_probe(struct ap_device *apdev)
*/
static void vfio_ap_queue_dev_remove(struct ap_device *apdev)
{
- struct vfio_ap_queue *q;
- int apid, apqi;
+ struct ap_queue *queue = to_ap_queue(&apdev->device);

mutex_lock(&matrix_dev->lock);
- q = dev_get_drvdata(&apdev->device);
- dev_set_drvdata(&apdev->device, NULL);
- apid = AP_QID_CARD(q->apqn);
- apqi = AP_QID_QUEUE(q->apqn);
- vfio_ap_mdev_reset_queue(apid, apqi, 1);
- vfio_ap_irq_disable(q);
- kfree(q);
+ vfio_ap_mdev_remove_queue(queue);
mutex_unlock(&matrix_dev->lock);
}

diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
index 0604b49a4d32..75a413fada4f 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -144,7 +144,7 @@ static void vfio_ap_free_aqic_resources(struct vfio_ap_queue *q)
* Returns if ap_aqic function failed with invalid, deconfigured or
* checkstopped AP.
*/
-struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q)
+static struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q)
{
struct ap_qirq_ctrl aqic_gisa = {};
struct ap_queue_status status;
@@ -1128,23 +1128,49 @@ static void vfio_ap_irq_disable_apqn(int apqn)
}
}

-int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi,
- unsigned int retry)
+static void vfio_ap_mdev_wait_for_qempty(ap_qid_t qid)
+{
+ struct ap_queue_status status;
+ int retry = 5;
+
+ do {
+ status = ap_tapq(qid, NULL);
+ switch (status.response_code) {
+ case AP_RESPONSE_NORMAL:
+ if (status.queue_empty)
+ return;
+ break;
+ case AP_RESPONSE_RESET_IN_PROGRESS:
+ case AP_RESPONSE_BUSY:
+ msleep(20);
+ break;
+ default:
+ pr_warn("%s: tapq response %02x waiting for queue %02x.%04x empty\n",
+ __func__, status.response_code,
+ AP_QID_CARD(qid), AP_QID_QUEUE(qid));
+ return;
+ }
+ } while (--retry);
+
+ WARN_ON_ONCE(retry <= 0);
+}
+
+static int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi)
{
struct ap_queue_status status;
- int retry2 = 2;
int apqn = AP_MKQID(apid, apqi);
+ int retry = 5;

do {
status = ap_zapq(apqn);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
- while (!status.queue_empty && retry2--) {
- msleep(20);
- status = ap_tapq(apqn, NULL);
- }
- WARN_ON_ONCE(retry <= 0);
+ if (!status.queue_empty)
+ vfio_ap_mdev_wait_for_qempty(AP_MKQID(apid,
+ apqi));
return 0;
+ case AP_RESPONSE_DECONFIGURED:
+ return -ENODEV;
case AP_RESPONSE_RESET_IN_PROGRESS:
case AP_RESPONSE_BUSY:
msleep(20);
@@ -1169,12 +1195,12 @@ static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev)
matrix_mdev->matrix.apm_max + 1) {
for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm,
matrix_mdev->matrix.aqm_max + 1) {
- ret = vfio_ap_mdev_reset_queue(apid, apqi, 1);
/*
* Regardless whether a queue turns out to be busy, or
* is not operational, we need to continue resetting
* the remaining queues.
*/
+ ret = vfio_ap_mdev_reset_queue(apid, apqi);
if (ret)
rc = ret;
vfio_ap_irq_disable_apqn(AP_MKQID(apid, apqi));
@@ -1302,3 +1328,31 @@ void vfio_ap_mdev_unregister(void)
{
mdev_unregister_device(&matrix_dev->device);
}
+
+int vfio_ap_mdev_probe_queue(struct ap_queue *queue)
+{
+ struct vfio_ap_queue *q;
+
+ q = kzalloc(sizeof(*q), GFP_KERNEL);
+ if (!q)
+ return -ENOMEM;
+ dev_set_drvdata(&queue->ap_dev.device, q);
+ q->apqn = queue->qid;
+ q->saved_isc = VFIO_AP_ISC_INVALID;
+
+ return 0;
+}
+
+void vfio_ap_mdev_remove_queue(struct ap_queue *queue)
+{
+ struct vfio_ap_queue *q;
+ int apid, apqi;
+
+ q = dev_get_drvdata(&queue->ap_dev.device);
+ dev_set_drvdata(&queue->ap_dev.device, NULL);
+ apid = AP_QID_CARD(q->apqn);
+ apqi = AP_QID_QUEUE(q->apqn);
+ vfio_ap_mdev_reset_queue(apid, apqi);
+ vfio_ap_irq_disable(q);
+ kfree(q);
+}
diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h
index f46dde56b464..5cc3c2ebf151 100644
--- a/drivers/s390/crypto/vfio_ap_private.h
+++ b/drivers/s390/crypto/vfio_ap_private.h
@@ -90,8 +90,6 @@ struct ap_matrix_mdev {

extern int vfio_ap_mdev_register(void);
extern void vfio_ap_mdev_unregister(void);
-int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi,
- unsigned int retry);

struct vfio_ap_queue {
struct ap_matrix_mdev *matrix_mdev;
@@ -100,5 +98,7 @@ struct vfio_ap_queue {
#define VFIO_AP_ISC_INVALID 0xff
unsigned char saved_isc;
};
-struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q);
+int vfio_ap_mdev_probe_queue(struct ap_queue *queue);
+void vfio_ap_mdev_remove_queue(struct ap_queue *queue);
+
#endif /* _VFIO_AP_PRIVATE_H_ */
--
2.7.4