[PATCH 04/10] vfio: ccw: replace IO_REQ event with SSCH_REQ event

Pierre Morel
2018-04-19T14:48:07Z

This patch simplifies the IO request handling to handle the only
implemented request: SSCH.
Other request are invalid and get a return value of -EINVAL.

This patch change the event name to VFIO_CCW_EVENT_SSCH_REQ to reflect
what is done and prepare for future implementation of other requests.

Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
---
drivers/s390/cio/vfio_ccw_fsm.c | 63 +++++++++++++------------------------
drivers/s390/cio/vfio_ccw_ops.c | 9 ++++--
drivers/s390/cio/vfio_ccw_private.h | 2 +-
3 files changed, 29 insertions(+), 45 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c
index 13751b4..f9855cd 100644
--- a/drivers/s390/cio/vfio_ccw_fsm.c
+++ b/drivers/s390/cio/vfio_ccw_fsm.c
@@ -19,14 +19,9 @@ static int fsm_io_helper(struct vfio_ccw_private *private)
union orb *orb;
int ccode;
__u8 lpm;
- unsigned long flags;

sch = private->sch;

- spin_lock_irqsave(sch->lock, flags);
- private->state = VFIO_CCW_STATE_BUSY;
- spin_unlock_irqrestore(sch->lock, flags);
-
orb = cp_get_orb(&private->cp, (u32)(addr_t)sch, sch->lpm);

/* Issue "Start Subchannel" */
@@ -118,44 +113,30 @@ static int fsm_io_request(struct vfio_ccw_private *private,
enum vfio_ccw_event event)
{
union orb *orb;
- union scsw *scsw = &private->scsw;
struct ccw_io_region *io_region = &private->io_region;
struct mdev_device *mdev = private->mdev;

private->state = VFIO_CCW_STATE_BOXED;

- memcpy(scsw, io_region->scsw_area, sizeof(*scsw));
-
- if (scsw->cmd.fctl & SCSW_FCTL_START_FUNC) {
- orb = (union orb *)io_region->orb_area;
-
- io_region->ret_code = cp_init(&private->cp, mdev_dev(mdev),
- orb);
- if (io_region->ret_code)
- goto err_out;
-
- io_region->ret_code = cp_prefetch(&private->cp);
- if (io_region->ret_code) {
- cp_free(&private->cp);
- goto err_out;
- }
-
- /* Start channel program and wait for I/O interrupt. */
- io_region->ret_code = fsm_io_helper(private);
- if (io_region->ret_code) {
- cp_free(&private->cp);
- goto err_out;
- }
- return private->state;
- } else if (scsw->cmd.fctl & SCSW_FCTL_HALT_FUNC) {
- /* XXX: Handle halt. */
- io_region->ret_code = -EOPNOTSUPP;
+ orb = (union orb *)io_region->orb_area;
+
+ io_region->ret_code = cp_init(&private->cp, mdev_dev(mdev), orb);
+ if (io_region->ret_code)
+ goto err_out;
+
+ io_region->ret_code = cp_prefetch(&private->cp);
+ if (io_region->ret_code) {
+ cp_free(&private->cp);
goto err_out;
- } else if (scsw->cmd.fctl & SCSW_FCTL_CLEAR_FUNC) {
- /* XXX: Handle clear. */
- io_region->ret_code = -EOPNOTSUPP;
+ }
+
+ /* Start channel program and wait for I/O interrupt. */
+ io_region->ret_code = fsm_io_helper(private);
+ if (io_region->ret_code) {
+ cp_free(&private->cp);
goto err_out;
}
+ return VFIO_CCW_STATE_BUSY;

err_out:
private->state = VFIO_CCW_STATE_IDLE;
@@ -179,7 +160,7 @@ static int fsm_irq(struct vfio_ccw_private *private,
if (private->io_trigger)
eventfd_signal(private->io_trigger, 1);

- return private->state;
+ return VFIO_CCW_STATE_IDLE;
}

/*
@@ -206,31 +187,31 @@ static int fsm_sch_event(struct vfio_ccw_private *private,
fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS] = {
[VFIO_CCW_STATE_NOT_OPER] = {
[VFIO_CCW_EVENT_NOT_OPER] = fsm_nop,
- [VFIO_CCW_EVENT_IO_REQ] = fsm_io_error,
+ [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_NOT_OPER] = fsm_notoper,
- [VFIO_CCW_EVENT_IO_REQ] = fsm_io_error,
+ [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_NOT_OPER] = fsm_notoper,
- [VFIO_CCW_EVENT_IO_REQ] = fsm_io_request,
+ [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_NOT_OPER] = fsm_notoper,
- [VFIO_CCW_EVENT_IO_REQ] = fsm_io_busy,
+ [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_NOT_OPER] = fsm_notoper,
- [VFIO_CCW_EVENT_IO_REQ] = fsm_io_busy,
+ [VFIO_CCW_EVENT_SSCH_REQ] = fsm_io_busy,
[VFIO_CCW_EVENT_INTERRUPT] = fsm_irq,
[VFIO_CCW_EVENT_SCH_EVENT] = fsm_sch_event,
},
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 41eeb57..4da7b61 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -188,19 +188,22 @@ static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev,
{
struct vfio_ccw_private *private;
struct ccw_io_region *region;
+ union scsw *scsw;

if (*ppos + count > sizeof(*region))
return -EINVAL;

private = dev_get_drvdata(mdev_parent_dev(mdev));
- if (private->state != VFIO_CCW_STATE_IDLE)
- return -EACCES;

region = &private->io_region;
if (copy_from_user((void *)region + *ppos, buf, count))
return -EFAULT;

- vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_IO_REQ);
+ scsw = (union scsw *) &region->scsw_area;
+ if ((scsw->cmd.fctl & SCSW_FCTL_START_FUNC) != SCSW_FCTL_START_FUNC)
+ return -EINVAL;
+
+ vfio_ccw_fsm_event(private, VFIO_CCW_EVENT_SSCH_REQ);
if (region->ret_code != 0) {
private->state = VFIO_CCW_STATE_IDLE;
return region->ret_code;
diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h
index 3284e64..93aab87 100644
--- a/drivers/s390/cio/vfio_ccw_private.h
+++ b/drivers/s390/cio/vfio_ccw_private.h
@@ -76,7 +76,7 @@ enum vfio_ccw_state {
*/
enum vfio_ccw_event {
VFIO_CCW_EVENT_NOT_OPER,
- VFIO_CCW_EVENT_IO_REQ,
+ VFIO_CCW_EVENT_SSCH_REQ,
VFIO_CCW_EVENT_INTERRUPT,
VFIO_CCW_EVENT_SCH_EVENT,
/* last element! */
--
2.7.4