[Intel-gfx] [PATCH v3 4/7] vfio/ccw: move private to mdev lifecycle

Eric Farman
2022-11-04T14:20:45Z

Now that the mdev parent data is split out into its own struct,
it is safe to move the remaining private data to follow the
mdev probe/remove lifecycle. The mdev parent data will remain
where it is, and follow the subchannel and the css driver
interfaces.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
---
drivers/s390/cio/vfio_ccw_drv.c | 16 +---------------
drivers/s390/cio/vfio_ccw_ops.c | 26 +++++++++++++-------------
drivers/s390/cio/vfio_ccw_private.h | 2 ++
3 files changed, 16 insertions(+), 28 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
index fbc26338ceab..9fbd1b27a1ac 100644
--- a/drivers/s390/cio/vfio_ccw_drv.c
+++ b/drivers/s390/cio/vfio_ccw_drv.c
@@ -152,7 +152,7 @@ static void vfio_ccw_sch_irq(struct subchannel *sch)
vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_INTERRUPT);
}

-static void vfio_ccw_free_private(struct vfio_ccw_private *private)
+void vfio_ccw_free_private(struct vfio_ccw_private *private)
{
struct vfio_ccw_crw *crw, *temp;

@@ -180,7 +180,6 @@ static void vfio_ccw_free_parent(struct device *dev)
static int vfio_ccw_sch_probe(struct subchannel *sch)
{
struct pmcw *pmcw = &sch->schib.pmcw;
- struct vfio_ccw_private *private;
struct vfio_ccw_parent *parent;
int ret = -ENOMEM;

@@ -201,14 +200,7 @@ static int vfio_ccw_sch_probe(struct subchannel *sch)
if (ret)
goto out_free;

- private = kzalloc(sizeof(*private), GFP_KERNEL);
- if (!private) {
- device_unregister(&parent->dev);
- return -ENOMEM;
- }
-
dev_set_drvdata(&sch->dev, parent);
- dev_set_drvdata(&parent->dev, private);

parent->mdev_type.sysfs_name = "io";
parent->mdev_type.pretty_name = "I/O subchannel (Non-QDIO)";
@@ -227,25 +219,19 @@ static int vfio_ccw_sch_probe(struct subchannel *sch)
out_unreg:
device_unregister(&parent->dev);
out_free:
- dev_set_drvdata(&parent->dev, NULL);
dev_set_drvdata(&sch->dev, NULL);
- if (private)
- vfio_ccw_free_private(private);
return ret;
}

static void vfio_ccw_sch_remove(struct subchannel *sch)
{
struct vfio_ccw_parent *parent = dev_get_drvdata(&sch->dev);
- struct vfio_ccw_private *private = dev_get_drvdata(&parent->dev);

mdev_unregister_parent(&parent->parent);

device_unregister(&parent->dev);
dev_set_drvdata(&sch->dev, NULL);

- vfio_ccw_free_private(private);
-
VFIO_CCW_MSG_EVENT(4, "unbound from subchannel %x.%x.%04x\n",
sch->schid.cssid, sch->schid.ssid,
sch->schid.sch_no);
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index eb0b8cc210bb..e45d4acb109b 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -100,15 +100,20 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
{
struct subchannel *sch = to_subchannel(mdev->dev.parent);
struct vfio_ccw_parent *parent = dev_get_drvdata(&sch->dev);
- struct vfio_ccw_private *private = dev_get_drvdata(&parent->dev);
+ struct vfio_ccw_private *private;
int ret;

- if (private->state == VFIO_CCW_STATE_NOT_OPER)
- return -ENODEV;
+ private = kzalloc(sizeof(*private), GFP_KERNEL);
+ if (!private)
+ return -ENOMEM;

ret = vfio_init_device(&private->vdev, &mdev->dev, &vfio_ccw_dev_ops);
- if (ret)
+ if (ret) {
+ kfree(private);
return ret;
+ }
+
+ dev_set_drvdata(&parent->dev, private);

VFIO_CCW_MSG_EVENT(2, "sch %x.%x.%04x: create\n",
sch->schid.cssid,
@@ -122,6 +127,7 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
return 0;

err_put_vdev:
+ dev_set_drvdata(&parent->dev, NULL);
vfio_put_device(&private->vdev);
return ret;
}
@@ -131,15 +137,6 @@ static void vfio_ccw_mdev_release_dev(struct vfio_device *vdev)
struct vfio_ccw_private *private =
container_of(vdev, struct vfio_ccw_private, vdev);

- /*
- * We cannot free vfio_ccw_private here because it includes
- * parent info which must be free'ed by css driver.
- *
- * Use a workaround by memset'ing the core device part and
- * then notifying the remove path that all active references
- * to this device have been released.
- */
- memset(vdev, 0, sizeof(*vdev));
complete(&private->release_comp);
}

@@ -156,6 +153,7 @@ static void vfio_ccw_mdev_remove(struct mdev_device *mdev)

vfio_unregister_group_dev(&private->vdev);

+ dev_set_drvdata(&parent->dev, NULL);
vfio_put_device(&private->vdev);
/*
* Wait for all active references on mdev are released so it
@@ -166,6 +164,8 @@ static void vfio_ccw_mdev_remove(struct mdev_device *mdev)
* 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 55d636225cff..747aba5f5272 100644
--- a/drivers/s390/cio/vfio_ccw_private.h
+++ b/drivers/s390/cio/vfio_ccw_private.h
@@ -134,6 +134,8 @@ int vfio_ccw_sch_quiesce(struct subchannel *sch);
void vfio_ccw_sch_io_todo(struct work_struct *work);
void vfio_ccw_crw_todo(struct work_struct *work);

+void vfio_ccw_free_private(struct vfio_ccw_private *private);
+
extern struct mdev_driver vfio_ccw_mdev_driver;

/*
--
2.34.1