On 6/9/21 9:52 AM, Jason J. Herne wrote:
On 5/10/21 12:44 PM, Tony Krowiak wrote:
This patch refactors the vfio_ap device driver to use the AP bus's
ap_get_qdev() function to retrieve the vfio_ap_queue struct containing
information about a queue that is bound to the vfio_ap device driver.
The bus's ap_get_qdev() function retrieves the queue device from a
hashtable keyed by APQN. This is much more efficient than looping over
the list of devices attached to the AP bus by several orders of
magnitude.
Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
Reviewed-by: Halil Pasic <pasic@xxxxxxxxxxxxx>
---
drivers/s390/crypto/vfio_ap_ops.c | 23 +++++++++--------------
1 file changed, 9 insertions(+), 14 deletions(-)
diff --git a/drivers/s390/crypto/vfio_ap_ops.c
b/drivers/s390/crypto/vfio_ap_ops.c
index 757166da947e..8a50aa650b65 100644
--- a/drivers/s390/crypto/vfio_ap_ops.c
+++ b/drivers/s390/crypto/vfio_ap_ops.c
@@ -27,13 +27,6 @@
static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev);
static struct vfio_ap_queue *vfio_ap_find_queue(int apqn);
-static int match_apqn(struct device *dev, const void *data)
-{
- struct vfio_ap_queue *q = dev_get_drvdata(dev);
-
- return (q->apqn == *(int *)(data)) ? 1 : 0;
-}
-
/**
* vfio_ap_get_queue: Retrieve a queue with a specific APQN from a
list
* @matrix_mdev: the associated mediated matrix
@@ -1253,15 +1246,17 @@ static int vfio_ap_mdev_group_notifier(struct
notifier_block *nb,
static struct vfio_ap_queue *vfio_ap_find_queue(int apqn)
{
- struct device *dev;
+ struct ap_queue *queue;
struct vfio_ap_queue *q = NULL;
The use of q and queue as variable names was a little confusing to me
at first. I tried renaming them a few times, the best I could come up
with was this:
I am (was) not a fan of the naming convention, but using 'q' to name a
struct vfio_ap_queue
was introduced (not by me) quite some time ago, so rather than
introducing a variable name
change at this juncture, I stuck with it to be consistent with the other
places it is used.
struct ap_queue *queue;
struct vfio_ap_queue *vfio_queue = NULL;
Take it or leave it :) Other than that, LGTM.
Reviewed-by: Jason J. Herne <jjherne@xxxxxxxxxxxxx>
Thanks for your review.
- dev = driver_find_device(&matrix_dev->vfio_ap_drv->driver, NULL,
- &apqn, match_apqn);
- if (dev) {
- q = dev_get_drvdata(dev);
- put_device(dev);
- }
+ queue = ap_get_qdev(apqn);
+ if (!queue)
+ return NULL;
+
+ if (queue->ap_dev.device.driver ==
&matrix_dev->vfio_ap_drv->driver)
+ q = dev_get_drvdata(&queue->ap_dev.device);
+
+ put_device(&queue->ap_dev.device);
return q;
}
