[PATCH 07/10] vfio: ccw: Introduce the INIT event

Pierre Morel
2018-04-19T14:48:10Z

The VFIO_CCW_EVENT_INIT event allows to export the initial state
into the FSM.

Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
---
drivers/s390/cio/vfio_ccw_drv.c | 26 +++++++++++---------------
drivers/s390/cio/vfio_ccw_fsm.c | 21 +++++++++++++++++++++
drivers/s390/cio/vfio_ccw_ops.c | 11 -----------
drivers/s390/cio/vfio_ccw_private.h | 1 +
4 files changed, 33 insertions(+), 26 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
index 1c9422a..f6e7def1 100644
--- a/drivers/s390/cio/vfio_ccw_drv.c
+++ b/drivers/s390/cio/vfio_ccw_drv.c
@@ -116,31 +116,27 @@ static int vfio_ccw_sch_probe(struct subchannel *sch)
private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA);
if (!private)
return -ENOMEM;
+
private->sch = sch;
dev_set_drvdata(&sch->dev, private);
mutex_init(&private->state_mutex);
-
- spin_lock_irq(sch->lock);
- private->state = VFIO_CCW_STATE_NOT_OPER;
- sch->isc = VFIO_CCW_ISC;
- ret = cio_enable_subchannel(sch, (u32)(unsigned long)sch);
- spin_unlock_irq(sch->lock);
- if (ret)
- goto out_free;
+ INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
+ INIT_WORK(&private->event_work, vfio_ccw_sch_event_todo);
+ atomic_set(&private->avail, 1);

ret = vfio_ccw_mdev_reg(sch);
if (ret)
- goto out_disable;
+ goto out_free;

- INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
- INIT_WORK(&private->event_work, vfio_ccw_sch_event_todo);
- atomic_set(&private->avail, 1);
- private->state = VFIO_CCW_STATE_STANDBY;
+ vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_INIT);
+ ret = -EFAULT;
+ if (private->state != VFIO_CCW_STATE_STANDBY)
+ goto out_unreg;

return 0;

-out_disable:
- cio_disable_subchannel(sch);
+out_unreg:
+ vfio_ccw_mdev_unreg(sch);
out_free:
dev_set_drvdata(&sch->dev, NULL);
kfree(private);
diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c
index d85bcfc..e8fe1e6 100644
--- a/drivers/s390/cio/vfio_ccw_fsm.c
+++ b/drivers/s390/cio/vfio_ccw_fsm.c
@@ -9,6 +9,7 @@

#include <linux/vfio.h>
#include <linux/mdev.h>
+#include <asm/isc.h>

#include "ioasm.h"
#include "vfio_ccw_private.h"
@@ -167,35 +168,55 @@ static int fsm_sch_event(struct vfio_ccw_private *private)
return ret;
}

+static int fsm_init(struct vfio_ccw_private *private)
+{
+ struct subchannel *sch = private->sch;
+ int ret = VFIO_CCW_STATE_STANDBY;
+
+ spin_lock_irq(sch->lock);
+ sch->isc = VFIO_CCW_ISC;
+ if (cio_enable_subchannel(sch, (u32)(unsigned long)sch))
+ ret = VFIO_CCW_STATE_NOT_OPER;
+ spin_unlock_irq(sch->lock);
+
+ return ret;
+}
+
+
/*
* Device statemachine
*/
fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS] = {
[VFIO_CCW_STATE_NOT_OPER] = {
+ [VFIO_CCW_EVENT_INIT] = fsm_init,
[VFIO_CCW_EVENT_NOT_OPER] = fsm_nop,
[VFIO_CCW_EVENT_SSCH_REQ] = fsm_io_error,
[VFIO_CCW_EVENT_INTERRUPT] = fsm_disabled_irq,
[VFIO_CCW_EVENT_SCH_EVENT] = fsm_nop,
},
[VFIO_CCW_STATE_STANDBY] = {
+ [VFIO_CCW_EVENT_INIT] = fsm_nop,
[VFIO_CCW_EVENT_NOT_OPER] = fsm_notoper,
[VFIO_CCW_EVENT_SSCH_REQ] = fsm_io_error,
[VFIO_CCW_EVENT_INTERRUPT] = fsm_irq,
[VFIO_CCW_EVENT_SCH_EVENT] = fsm_sch_event,
},
[VFIO_CCW_STATE_IDLE] = {
+ [VFIO_CCW_EVENT_INIT] = fsm_nop,
[VFIO_CCW_EVENT_NOT_OPER] = fsm_notoper,
[VFIO_CCW_EVENT_SSCH_REQ] = fsm_io_request,
[VFIO_CCW_EVENT_INTERRUPT] = fsm_irq,
[VFIO_CCW_EVENT_SCH_EVENT] = fsm_sch_event,
},
[VFIO_CCW_STATE_BOXED] = {
+ [VFIO_CCW_EVENT_INIT] = fsm_nop,
[VFIO_CCW_EVENT_NOT_OPER] = fsm_notoper,
[VFIO_CCW_EVENT_SSCH_REQ] = fsm_io_busy,
[VFIO_CCW_EVENT_INTERRUPT] = fsm_irq,
[VFIO_CCW_EVENT_SCH_EVENT] = fsm_sch_event,
},
[VFIO_CCW_STATE_BUSY] = {
+ [VFIO_CCW_EVENT_INIT] = fsm_nop,
[VFIO_CCW_EVENT_NOT_OPER] = fsm_notoper,
[VFIO_CCW_EVENT_SSCH_REQ] = fsm_io_busy,
[VFIO_CCW_EVENT_INTERRUPT] = fsm_irq,
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index dac8ce4..78d1925 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -111,14 +111,10 @@ static int vfio_ccw_mdev_create(struct kobject *kobj, struct mdev_device *mdev)
struct vfio_ccw_private *private =
dev_get_drvdata(mdev_parent_dev(mdev));

- if (private->state == VFIO_CCW_STATE_NOT_OPER)
- return -ENODEV;
-
if (atomic_dec_if_positive(&private->avail) < 0)
return -EPERM;

private->mdev = mdev;
- private->state = VFIO_CCW_STATE_IDLE;

return 0;
}
@@ -128,13 +124,6 @@ static int vfio_ccw_mdev_remove(struct mdev_device *mdev)
struct vfio_ccw_private *private =
dev_get_drvdata(mdev_parent_dev(mdev));

- if ((private->state != VFIO_CCW_STATE_NOT_OPER) &&
- (private->state != VFIO_CCW_STATE_STANDBY)) {
- if (!vfio_ccw_mdev_reset(mdev))
- private->state = VFIO_CCW_STATE_STANDBY;
- /* The state will be NOT_OPER on error. */
- }
-
private->mdev = NULL;
atomic_inc(&private->avail);

diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h
index cf197cf..cacf677 100644
--- a/drivers/s390/cio/vfio_ccw_private.h
+++ b/drivers/s390/cio/vfio_ccw_private.h
@@ -76,6 +76,7 @@ enum vfio_ccw_state {
* Asynchronous events of the device statemachine.
*/
enum vfio_ccw_event {
+ VFIO_CCW_EVENT_INIT,
VFIO_CCW_EVENT_NOT_OPER,
VFIO_CCW_EVENT_SSCH_REQ,
VFIO_CCW_EVENT_INTERRUPT,
--
2.7.4