[PATCH v3 5/7] vfio/ccw: remove release completion

From: Eric Farman
Date: Fri Nov 04 2022 - 10:21:46 EST


There's enough separation between the parent and private structs now,
that it is fine to remove the release completion hack.

Signed-off-by: Eric Farman <farman@xxxxxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Reviewed-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
---
drivers/s390/cio/vfio_ccw_ops.c | 14 +-------------
drivers/s390/cio/vfio_ccw_private.h | 3 ---
2 files changed, 1 insertion(+), 16 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index e45d4acb109b..8a929a9cf3c6 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -54,7 +54,6 @@ static int vfio_ccw_mdev_init_dev(struct vfio_device *vdev)
INIT_LIST_HEAD(&private->crw);
INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
INIT_WORK(&private->crw_work, vfio_ccw_crw_todo);
- init_completion(&private->release_comp);

private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct ccw1),
GFP_KERNEL);
@@ -137,7 +136,7 @@ static void vfio_ccw_mdev_release_dev(struct vfio_device *vdev)
struct vfio_ccw_private *private =
container_of(vdev, struct vfio_ccw_private, vdev);

- complete(&private->release_comp);
+ vfio_ccw_free_private(private);
}

static void vfio_ccw_mdev_remove(struct mdev_device *mdev)
@@ -155,17 +154,6 @@ static void vfio_ccw_mdev_remove(struct mdev_device *mdev)

dev_set_drvdata(&parent->dev, NULL);
vfio_put_device(&private->vdev);
- /*
- * Wait for all active references on mdev are released so it
- * is safe to defer kfree() to a later point.
- *
- * TODO: the clean fix is to split parent/mdev info from ccw
- * private structure so each can be managed in its own life
- * cycle.
- */
- wait_for_completion(&private->release_comp);
-
- vfio_ccw_free_private(private);
}

static int vfio_ccw_mdev_open_device(struct vfio_device *vdev)
diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h
index 747aba5f5272..2278fd38d34e 100644
--- a/drivers/s390/cio/vfio_ccw_private.h
+++ b/drivers/s390/cio/vfio_ccw_private.h
@@ -102,7 +102,6 @@ struct vfio_ccw_parent {
* @req_trigger: eventfd ctx for signaling userspace to return device
* @io_work: work for deferral process of I/O handling
* @crw_work: work for deferral process of CRW handling
- * @release_comp: synchronization helper for vfio device release
*/
struct vfio_ccw_private {
struct vfio_device vdev;
@@ -126,8 +125,6 @@ struct vfio_ccw_private {
struct eventfd_ctx *req_trigger;
struct work_struct io_work;
struct work_struct crw_work;
-
- struct completion release_comp;
} __aligned(8);

int vfio_ccw_sch_quiesce(struct subchannel *sch);
--
2.34.1