[PATCH v3 3/8] vfio: ccw: new VFIO_CCW_EVENT_SCHIB_CHANGED event

2018-06-12 Thread Pierre Morel
From: Pierre Morel 

The Sub channel event callback is threaded using workqueues.
The work uses the FSM introducing the VFIO_CCW_EVENT_SCHIB_CHANGED
event.
The update of the SCHIB is now done inside the FSM function.

Signed-off-by: Pierre Morel 
---
 drivers/s390/cio/vfio_ccw_drv.c | 33 -
 drivers/s390/cio/vfio_ccw_fsm.c | 23 +++
 drivers/s390/cio/vfio_ccw_private.h |  3 +++
 3 files changed, 38 insertions(+), 21 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
index 095a2d9..e5a516a 100644
--- a/drivers/s390/cio/vfio_ccw_drv.c
+++ b/drivers/s390/cio/vfio_ccw_drv.c
@@ -75,6 +75,14 @@ static void vfio_ccw_sch_io_todo(struct work_struct *work)
vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_INTERRUPT);
 }
 
+static void vfio_ccw_sch_event_todo(struct work_struct *work)
+{
+   struct vfio_ccw_private *private;
+
+   private = container_of(work, struct vfio_ccw_private, event_work);
+   vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_SCHIB_CHANGED);
+}
+
 /*
  * Css driver callbacks
  */
@@ -122,6 +130,7 @@ static int vfio_ccw_sch_probe(struct subchannel *sch)
goto out_disable;
 
INIT_WORK(>io_work, vfio_ccw_sch_io_todo);
+   INIT_WORK(>event_work, vfio_ccw_sch_event_todo);
atomic_set(>avail, 1);
private->state = VFIO_CCW_STATE_STANDBY;
 
@@ -168,28 +177,10 @@ static void vfio_ccw_sch_shutdown(struct subchannel *sch)
 static int vfio_ccw_sch_event(struct subchannel *sch, int process)
 {
struct vfio_ccw_private *private = dev_get_drvdata(>dev);
-   unsigned long flags;
-
-   spin_lock_irqsave(sch->lock, flags);
-   if (!device_is_registered(>dev))
-   goto out_unlock;
 
-   if (work_pending(>todo_work))
-   goto out_unlock;
-
-   if (cio_update_schib(sch)) {
-   vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_NOT_OPER);
-   goto out_unlock;
-   }
-
-   private = dev_get_drvdata(>dev);
-   if (private->state == VFIO_CCW_STATE_NOT_OPER) {
-   private->state = private->mdev ? VFIO_CCW_STATE_IDLE :
-VFIO_CCW_STATE_STANDBY;
-   }
-
-out_unlock:
-   spin_unlock_irqrestore(sch->lock, flags);
+   if (work_pending(>event_work))
+   return -EAGAIN;
+   queue_work(vfio_ccw_work_q, >event_work);
 
return 0;
 }
diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c
index 1a0585f..94bf151 100644
--- a/drivers/s390/cio/vfio_ccw_fsm.c
+++ b/drivers/s390/cio/vfio_ccw_fsm.c
@@ -191,6 +191,24 @@ static int fsm_irq(struct vfio_ccw_private *private,
 }
 
 /*
+ * Got a sub-channel event .
+ */
+static int fsm_sch_event(struct vfio_ccw_private *private,
+enum vfio_ccw_event event)
+{
+   unsigned long flags;
+   int ret = private->state;
+   struct subchannel *sch = private->sch;
+
+   spin_lock_irqsave(sch->lock, flags);
+   if (cio_update_schib(sch))
+   ret = VFIO_CCW_STATE_NOT_OPER;
+   spin_unlock_irqrestore(sch->lock, flags);
+
+   return ret;
+}
+
+/*
  * Device statemachine
  */
 fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS] = {
@@ -198,25 +216,30 @@ fsm_func_t 
*vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS] = {
[VFIO_CCW_EVENT_NOT_OPER]   = fsm_nop,
[VFIO_CCW_EVENT_IO_REQ] = fsm_io_error,
[VFIO_CCW_EVENT_INTERRUPT]  = fsm_disabled_irq,
+   [VFIO_CCW_EVENT_SCHIB_CHANGED]  = fsm_nop,
},
[VFIO_CCW_STATE_STANDBY] = {
[VFIO_CCW_EVENT_NOT_OPER]   = fsm_notoper,
[VFIO_CCW_EVENT_IO_REQ] = fsm_io_error,
[VFIO_CCW_EVENT_INTERRUPT]  = fsm_irq,
+   [VFIO_CCW_EVENT_SCHIB_CHANGED]  = fsm_sch_event,
},
[VFIO_CCW_STATE_IDLE] = {
[VFIO_CCW_EVENT_NOT_OPER]   = fsm_notoper,
[VFIO_CCW_EVENT_IO_REQ] = fsm_io_request,
[VFIO_CCW_EVENT_INTERRUPT]  = fsm_irq,
+   [VFIO_CCW_EVENT_SCHIB_CHANGED]  = fsm_sch_event,
},
[VFIO_CCW_STATE_BOXED] = {
[VFIO_CCW_EVENT_NOT_OPER]   = fsm_notoper,
[VFIO_CCW_EVENT_IO_REQ] = fsm_io_busy,
[VFIO_CCW_EVENT_INTERRUPT]  = fsm_irq,
+   [VFIO_CCW_EVENT_SCHIB_CHANGED]  = fsm_sch_event,
},
[VFIO_CCW_STATE_BUSY] = {
[VFIO_CCW_EVENT_NOT_OPER]   = fsm_notoper,
[VFIO_CCW_EVENT_IO_REQ] = fsm_io_busy,
[VFIO_CCW_EVENT_INTERRUPT]  = fsm_irq,
+   [VFIO_CCW_EVENT_SCHIB_CHANGED]  = fsm_sch_event,
},
 };
diff --git a/drivers/s390/cio/vfio_ccw_private.h 
b/drivers/s390/cio/vfio_ccw_private.h
index f526b18..a2be0c9 100644
--- 

[PATCH v3 3/8] vfio: ccw: new VFIO_CCW_EVENT_SCHIB_CHANGED event

2018-06-12 Thread Pierre Morel
From: Pierre Morel 

The Sub channel event callback is threaded using workqueues.
The work uses the FSM introducing the VFIO_CCW_EVENT_SCHIB_CHANGED
event.
The update of the SCHIB is now done inside the FSM function.

Signed-off-by: Pierre Morel 
---
 drivers/s390/cio/vfio_ccw_drv.c | 33 -
 drivers/s390/cio/vfio_ccw_fsm.c | 23 +++
 drivers/s390/cio/vfio_ccw_private.h |  3 +++
 3 files changed, 38 insertions(+), 21 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
index 095a2d9..e5a516a 100644
--- a/drivers/s390/cio/vfio_ccw_drv.c
+++ b/drivers/s390/cio/vfio_ccw_drv.c
@@ -75,6 +75,14 @@ static void vfio_ccw_sch_io_todo(struct work_struct *work)
vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_INTERRUPT);
 }
 
+static void vfio_ccw_sch_event_todo(struct work_struct *work)
+{
+   struct vfio_ccw_private *private;
+
+   private = container_of(work, struct vfio_ccw_private, event_work);
+   vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_SCHIB_CHANGED);
+}
+
 /*
  * Css driver callbacks
  */
@@ -122,6 +130,7 @@ static int vfio_ccw_sch_probe(struct subchannel *sch)
goto out_disable;
 
INIT_WORK(>io_work, vfio_ccw_sch_io_todo);
+   INIT_WORK(>event_work, vfio_ccw_sch_event_todo);
atomic_set(>avail, 1);
private->state = VFIO_CCW_STATE_STANDBY;
 
@@ -168,28 +177,10 @@ static void vfio_ccw_sch_shutdown(struct subchannel *sch)
 static int vfio_ccw_sch_event(struct subchannel *sch, int process)
 {
struct vfio_ccw_private *private = dev_get_drvdata(>dev);
-   unsigned long flags;
-
-   spin_lock_irqsave(sch->lock, flags);
-   if (!device_is_registered(>dev))
-   goto out_unlock;
 
-   if (work_pending(>todo_work))
-   goto out_unlock;
-
-   if (cio_update_schib(sch)) {
-   vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_NOT_OPER);
-   goto out_unlock;
-   }
-
-   private = dev_get_drvdata(>dev);
-   if (private->state == VFIO_CCW_STATE_NOT_OPER) {
-   private->state = private->mdev ? VFIO_CCW_STATE_IDLE :
-VFIO_CCW_STATE_STANDBY;
-   }
-
-out_unlock:
-   spin_unlock_irqrestore(sch->lock, flags);
+   if (work_pending(>event_work))
+   return -EAGAIN;
+   queue_work(vfio_ccw_work_q, >event_work);
 
return 0;
 }
diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c
index 1a0585f..94bf151 100644
--- a/drivers/s390/cio/vfio_ccw_fsm.c
+++ b/drivers/s390/cio/vfio_ccw_fsm.c
@@ -191,6 +191,24 @@ static int fsm_irq(struct vfio_ccw_private *private,
 }
 
 /*
+ * Got a sub-channel event .
+ */
+static int fsm_sch_event(struct vfio_ccw_private *private,
+enum vfio_ccw_event event)
+{
+   unsigned long flags;
+   int ret = private->state;
+   struct subchannel *sch = private->sch;
+
+   spin_lock_irqsave(sch->lock, flags);
+   if (cio_update_schib(sch))
+   ret = VFIO_CCW_STATE_NOT_OPER;
+   spin_unlock_irqrestore(sch->lock, flags);
+
+   return ret;
+}
+
+/*
  * Device statemachine
  */
 fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS] = {
@@ -198,25 +216,30 @@ fsm_func_t 
*vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS] = {
[VFIO_CCW_EVENT_NOT_OPER]   = fsm_nop,
[VFIO_CCW_EVENT_IO_REQ] = fsm_io_error,
[VFIO_CCW_EVENT_INTERRUPT]  = fsm_disabled_irq,
+   [VFIO_CCW_EVENT_SCHIB_CHANGED]  = fsm_nop,
},
[VFIO_CCW_STATE_STANDBY] = {
[VFIO_CCW_EVENT_NOT_OPER]   = fsm_notoper,
[VFIO_CCW_EVENT_IO_REQ] = fsm_io_error,
[VFIO_CCW_EVENT_INTERRUPT]  = fsm_irq,
+   [VFIO_CCW_EVENT_SCHIB_CHANGED]  = fsm_sch_event,
},
[VFIO_CCW_STATE_IDLE] = {
[VFIO_CCW_EVENT_NOT_OPER]   = fsm_notoper,
[VFIO_CCW_EVENT_IO_REQ] = fsm_io_request,
[VFIO_CCW_EVENT_INTERRUPT]  = fsm_irq,
+   [VFIO_CCW_EVENT_SCHIB_CHANGED]  = fsm_sch_event,
},
[VFIO_CCW_STATE_BOXED] = {
[VFIO_CCW_EVENT_NOT_OPER]   = fsm_notoper,
[VFIO_CCW_EVENT_IO_REQ] = fsm_io_busy,
[VFIO_CCW_EVENT_INTERRUPT]  = fsm_irq,
+   [VFIO_CCW_EVENT_SCHIB_CHANGED]  = fsm_sch_event,
},
[VFIO_CCW_STATE_BUSY] = {
[VFIO_CCW_EVENT_NOT_OPER]   = fsm_notoper,
[VFIO_CCW_EVENT_IO_REQ] = fsm_io_busy,
[VFIO_CCW_EVENT_INTERRUPT]  = fsm_irq,
+   [VFIO_CCW_EVENT_SCHIB_CHANGED]  = fsm_sch_event,
},
 };
diff --git a/drivers/s390/cio/vfio_ccw_private.h 
b/drivers/s390/cio/vfio_ccw_private.h
index f526b18..a2be0c9 100644
---