[Intel-gfx] [PATCH v2 7/9] vfio/ccw: Remove private->mdev

Jason Gunthorpe
2021-09-09T19:39:08Z

Having a mdev pointer floating about in addition to a struct vfio_device
is confusing. It is only used for three things:

- Getting the mdev 'struct device *' - this is the same as
private->vdev.dev

- Printing the uuid of the mdev in logging. The uuid is also the dev_name
of the mdev so this is the same string as
dev_name(private->vdev.dev)

- A weird attempt to fence the vfio_ccw_sch_io_todo() work. This work is
only queued during states IDLE/PROCESSING/PENDING and flushed when
entering CLOSED. Thus the work already cannot run when the mdev is NULL.
Remove it.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
drivers/s390/cio/vfio_ccw_drv.c | 6 ++--
drivers/s390/cio/vfio_ccw_fsm.c | 48 +++++++++++++----------------
drivers/s390/cio/vfio_ccw_ops.c | 16 ++++------
drivers/s390/cio/vfio_ccw_private.h | 2 --
include/linux/mdev.h | 4 ---
5 files changed, 30 insertions(+), 46 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
index de782e967a5474..0e2edd96567a09 100644
--- a/drivers/s390/cio/vfio_ccw_drv.c
+++ b/drivers/s390/cio/vfio_ccw_drv.c
@@ -64,7 +64,7 @@ static void vfio_ccw_sch_io_todo(struct work_struct *work)
* has finished. Do not overwrite a possible processing
* state if the final interrupt was for HSCH or CSCH.
*/
- if (private->mdev && cp_is_finished)
+ if (cp_is_finished)
private->state = VFIO_CCW_STATE_IDLE;

if (private->io_trigger)
@@ -303,8 +303,8 @@ static int vfio_ccw_chp_event(struct subchannel *sch,
return 0;

trace_vfio_ccw_chp_event(private->sch->schid, mask, event);
- VFIO_CCW_MSG_EVENT(2, "%pUl (%x.%x.%04x): mask=0x%x event=%d\n",
- mdev_uuid(private->mdev), sch->schid.cssid,
+ VFIO_CCW_MSG_EVENT(2, "%s (%x.%x.%04x): mask=0x%x event=%d\n",
+ dev_name(private->vdev.dev), sch->schid.cssid,
sch->schid.ssid, sch->schid.sch_no,
mask, event);

diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c
index 302215090b9ac7..df1490943b20ec 100644
--- a/drivers/s390/cio/vfio_ccw_fsm.c
+++ b/drivers/s390/cio/vfio_ccw_fsm.c
@@ -245,7 +245,6 @@ static void fsm_io_request(struct vfio_ccw_private *private,
union orb *orb;
union scsw *scsw = &private->scsw;
struct ccw_io_region *io_region = private->io_region;
- struct mdev_device *mdev = private->mdev;
char *errstr = "request";
struct subchannel_id schid = get_schid(private);

@@ -258,32 +257,30 @@ static void fsm_io_request(struct vfio_ccw_private *private,
/* Don't try to build a cp if transport mode is specified. */
if (orb->tm.b) {
io_region->ret_code = -EOPNOTSUPP;
- VFIO_CCW_MSG_EVENT(2,
- "%pUl (%x.%x.%04x): transport mode\n",
- mdev_uuid(mdev), schid.cssid,
- schid.ssid, schid.sch_no);
+ VFIO_CCW_MSG_EVENT(
+ 2, "%s (%x.%x.%04x): transport mode\n",
+ dev_name(private->vdev.dev), schid.cssid,
+ schid.ssid, schid.sch_no);
errstr = "transport mode";
goto err_out;
}
- io_region->ret_code = cp_init(&private->cp, mdev_dev(mdev),
+ io_region->ret_code = cp_init(&private->cp, private->vdev.dev,
orb);
if (io_region->ret_code) {
- VFIO_CCW_MSG_EVENT(2,
- "%pUl (%x.%x.%04x): cp_init=%d\n",
- mdev_uuid(mdev), schid.cssid,
- schid.ssid, schid.sch_no,
- io_region->ret_code);
+ VFIO_CCW_MSG_EVENT(2, "%s (%x.%x.%04x): cp_init=%d\n",
+ dev_name(private->vdev.dev),
+ schid.cssid, schid.ssid,
+ schid.sch_no, io_region->ret_code);
errstr = "cp init";
goto err_out;
}

io_region->ret_code = cp_prefetch(&private->cp);
if (io_region->ret_code) {
- VFIO_CCW_MSG_EVENT(2,
- "%pUl (%x.%x.%04x): cp_prefetch=%d\n",
- mdev_uuid(mdev), schid.cssid,
- schid.ssid, schid.sch_no,
- io_region->ret_code);
+ VFIO_CCW_MSG_EVENT(
+ 2, "%s (%x.%x.%04x): cp_prefetch=%d\n",
+ dev_name(private->vdev.dev), schid.cssid,
+ schid.ssid, schid.sch_no, io_region->ret_code);
errstr = "cp prefetch";
cp_free(&private->cp);
goto err_out;
@@ -292,28 +289,25 @@ static void fsm_io_request(struct vfio_ccw_private *private,
/* Start channel program and wait for I/O interrupt. */
io_region->ret_code = fsm_io_helper(private);
if (io_region->ret_code) {
- VFIO_CCW_MSG_EVENT(2,
- "%pUl (%x.%x.%04x): fsm_io_helper=%d\n",
- mdev_uuid(mdev), schid.cssid,
- schid.ssid, schid.sch_no,
- io_region->ret_code);
+ VFIO_CCW_MSG_EVENT(
+ 2, "%s (%x.%x.%04x): fsm_io_helper=%d\n",
+ dev_name(private->vdev.dev), schid.cssid,
+ schid.ssid, schid.sch_no, io_region->ret_code);
errstr = "cp fsm_io_helper";
cp_free(&private->cp);
goto err_out;
}
return;
} else if (scsw->cmd.fctl & SCSW_FCTL_HALT_FUNC) {
- VFIO_CCW_MSG_EVENT(2,
- "%pUl (%x.%x.%04x): halt on io_region\n",
- mdev_uuid(mdev), schid.cssid,
+ VFIO_CCW_MSG_EVENT(2, "%s (%x.%x.%04x): halt on io_region\n",
+ dev_name(private->vdev.dev), schid.cssid,
schid.ssid, schid.sch_no);
/* halt is handled via the async cmd region */
io_region->ret_code = -EOPNOTSUPP;
goto err_out;
} else if (scsw->cmd.fctl & SCSW_FCTL_CLEAR_FUNC) {
- VFIO_CCW_MSG_EVENT(2,
- "%pUl (%x.%x.%04x): clear on io_region\n",
- mdev_uuid(mdev), schid.cssid,
+ VFIO_CCW_MSG_EVENT(2, "%s (%x.%x.%04x): clear on io_region\n",
+ dev_name(private->vdev.dev), schid.cssid,
schid.ssid, schid.sch_no);
/* clear is handled via the async cmd region */
io_region->ret_code = -EOPNOTSUPP;
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 38ab5c1f25ec09..23004e67c492f6 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -95,11 +95,9 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
vfio_init_group_dev(&private->vdev, &mdev->dev,
&vfio_ccw_dev_ops);

- private->mdev = mdev;
-
- VFIO_CCW_MSG_EVENT(2, "mdev %pUl, sch %x.%x.%04x: create\n",
- mdev_uuid(mdev), private->sch->schid.cssid,
- private->sch->schid.ssid,
+ VFIO_CCW_MSG_EVENT(2, "mdev %s, sch %x.%x.%04x: create\n",
+ dev_name(private->vdev.dev),
+ private->sch->schid.cssid, private->sch->schid.ssid,
private->sch->schid.sch_no);

ret = vfio_register_group_dev(&private->vdev);
@@ -110,7 +108,6 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev)

err_init:
vfio_uninit_group_dev(&private->vdev);
- private->mdev = NULL;
return ret;
}

@@ -118,14 +115,13 @@ static void vfio_ccw_mdev_remove(struct mdev_device *mdev)
{
struct vfio_ccw_private *private = dev_get_drvdata(mdev->dev.parent);

- VFIO_CCW_MSG_EVENT(2, "mdev %pUl, sch %x.%x.%04x: remove\n",
- mdev_uuid(mdev), private->sch->schid.cssid,
- private->sch->schid.ssid,
+ VFIO_CCW_MSG_EVENT(2, "mdev %s, sch %x.%x.%04x: remove\n",
+ dev_name(private->vdev.dev),
+ private->sch->schid.cssid, private->sch->schid.ssid,
private->sch->schid.sch_no);

vfio_unregister_group_dev(&private->vdev);
vfio_uninit_group_dev(&private->vdev);
- private->mdev = NULL;
}

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 bbc97eb9d9c6fc..67ee9c624393b0 100644
--- a/drivers/s390/cio/vfio_ccw_private.h
+++ b/drivers/s390/cio/vfio_ccw_private.h
@@ -72,7 +72,6 @@ struct vfio_ccw_crw {
* @sch: pointer to the subchannel
* @state: internal state of the device
* @completion: synchronization helper of the I/O completion
- * @mdev: pointer to the mediated device
* @nb: notifier for vfio events
* @io_region: MMIO region to input/output I/O arguments/results
* @io_mutex: protect against concurrent update of I/O regions
@@ -95,7 +94,6 @@ struct vfio_ccw_private {
struct subchannel *sch;
int state;
struct completion *completion;
- struct mdev_device *mdev;
struct notifier_block nb;
struct ccw_io_region *io_region;
struct mutex io_mutex;
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 819eaf98ffac73..ea59610d45fd89 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -158,10 +158,6 @@ static inline void mdev_set_drvdata(struct mdev_device *mdev, void *data)
{
mdev->driver_data = data;
}
-static inline const guid_t *mdev_uuid(struct mdev_device *mdev)
-{
- return &mdev->uuid;
-}

extern struct bus_type mdev_bus_type;

--
2.33.0