[Intel-gfx] [PATCH v2 2/7] vfio/ccw: remove private->sch

Eric Farman
2022-11-02T15:02:07Z

These places all rely on the ability to jump from a private
struct back to the subchannel struct. Rather than keeping a
copy in our back pocket, let's use the relationship provided
by the vfio_device embedded within the private.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
---
drivers/s390/cio/vfio_ccw_chp.c | 5 +++--
drivers/s390/cio/vfio_ccw_drv.c | 3 +--
drivers/s390/cio/vfio_ccw_fsm.c | 27 ++++++++++++---------------
drivers/s390/cio/vfio_ccw_ops.c | 12 ++++++------
drivers/s390/cio/vfio_ccw_private.h | 7 ++++---
5 files changed, 26 insertions(+), 28 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_chp.c b/drivers/s390/cio/vfio_ccw_chp.c
index 13b26a1c7988..d3f3a611f95b 100644
--- a/drivers/s390/cio/vfio_ccw_chp.c
+++ b/drivers/s390/cio/vfio_ccw_chp.c
@@ -16,6 +16,7 @@ static ssize_t vfio_ccw_schib_region_read(struct vfio_ccw_private *private,
char __user *buf, size_t count,
loff_t *ppos)
{
+ struct subchannel *sch = to_subchannel(private->vdev.dev->parent);
unsigned int i = VFIO_CCW_OFFSET_TO_INDEX(*ppos) - VFIO_CCW_NUM_REGIONS;
loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK;
struct ccw_schib_region *region;
@@ -27,12 +28,12 @@ static ssize_t vfio_ccw_schib_region_read(struct vfio_ccw_private *private,
mutex_lock(&private->io_mutex);
region = private->region[i].data;

- if (cio_update_schib(private->sch)) {
+ if (cio_update_schib(sch)) {
ret = -ENODEV;
goto out;
}

- memcpy(region, &private->sch->schib, sizeof(*region));
+ memcpy(region, &sch->schib, sizeof(*region));

if (copy_to_user(buf, (void *)region + pos, count)) {
ret = -EFAULT;
diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
index 06022fb37b9d..1ba2a9971f86 100644
--- a/drivers/s390/cio/vfio_ccw_drv.c
+++ b/drivers/s390/cio/vfio_ccw_drv.c
@@ -159,7 +159,6 @@ static struct vfio_ccw_private *vfio_ccw_alloc_private(struct subchannel *sch)
if (!private)
return ERR_PTR(-ENOMEM);

- private->sch = sch;
mutex_init(&private->io_mutex);
private->state = VFIO_CCW_STATE_STANDBY;
INIT_LIST_HEAD(&private->crw);
@@ -395,7 +394,7 @@ static int vfio_ccw_chp_event(struct subchannel *sch,
if (!private || !mask)
return 0;

- trace_vfio_ccw_chp_event(private->sch->schid, mask, event);
+ trace_vfio_ccw_chp_event(sch->schid, mask, event);
VFIO_CCW_MSG_EVENT(2, "sch %x.%x.%04x: mask=0x%x event=%d\n",
sch->schid.cssid,
sch->schid.ssid, sch->schid.sch_no,
diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c
index a59c758869f8..e67fad897af3 100644
--- a/drivers/s390/cio/vfio_ccw_fsm.c
+++ b/drivers/s390/cio/vfio_ccw_fsm.c
@@ -18,15 +18,13 @@

static int fsm_io_helper(struct vfio_ccw_private *private)
{
- struct subchannel *sch;
+ struct subchannel *sch = to_subchannel(private->vdev.dev->parent);
union orb *orb;
int ccode;
__u8 lpm;
unsigned long flags;
int ret;

- sch = private->sch;
-
spin_lock_irqsave(sch->lock, flags);

orb = cp_get_orb(&private->cp, (u32)(addr_t)sch, sch->lpm);
@@ -80,13 +78,11 @@ static int fsm_io_helper(struct vfio_ccw_private *private)

static int fsm_do_halt(struct vfio_ccw_private *private)
{
- struct subchannel *sch;
+ struct subchannel *sch = to_subchannel(private->vdev.dev->parent);
unsigned long flags;
int ccode;
int ret;

- sch = private->sch;
-
spin_lock_irqsave(sch->lock, flags);

VFIO_CCW_TRACE_EVENT(2, "haltIO");
@@ -121,13 +117,11 @@ static int fsm_do_halt(struct vfio_ccw_private *private)

static int fsm_do_clear(struct vfio_ccw_private *private)
{
- struct subchannel *sch;
+ struct subchannel *sch = to_subchannel(private->vdev.dev->parent);
unsigned long flags;
int ccode;
int ret;

- sch = private->sch;
-
spin_lock_irqsave(sch->lock, flags);

VFIO_CCW_TRACE_EVENT(2, "clearIO");
@@ -160,7 +154,7 @@ static int fsm_do_clear(struct vfio_ccw_private *private)
static void fsm_notoper(struct vfio_ccw_private *private,
enum vfio_ccw_event event)
{
- struct subchannel *sch = private->sch;
+ struct subchannel *sch = to_subchannel(private->vdev.dev->parent);

VFIO_CCW_MSG_EVENT(2, "sch %x.%x.%04x: notoper event %x state %x\n",
sch->schid.cssid,
@@ -228,7 +222,7 @@ static void fsm_async_retry(struct vfio_ccw_private *private,
static void fsm_disabled_irq(struct vfio_ccw_private *private,
enum vfio_ccw_event event)
{
- struct subchannel *sch = private->sch;
+ struct subchannel *sch = to_subchannel(private->vdev.dev->parent);

/*
* An interrupt in a disabled state means a previous disable was not
@@ -238,7 +232,9 @@ static void fsm_disabled_irq(struct vfio_ccw_private *private,
}
inline struct subchannel_id get_schid(struct vfio_ccw_private *p)
{
- return p->sch->schid;
+ struct subchannel *sch = to_subchannel(p->vdev.dev->parent);
+
+ return sch->schid;
}

/*
@@ -360,10 +356,11 @@ static void fsm_async_request(struct vfio_ccw_private *private,
static void fsm_irq(struct vfio_ccw_private *private,
enum vfio_ccw_event event)
{
+ struct subchannel *sch = to_subchannel(private->vdev.dev->parent);
struct irb *irb = this_cpu_ptr(&cio_irb);

VFIO_CCW_TRACE_EVENT(6, "IRQ");
- VFIO_CCW_TRACE_EVENT(6, dev_name(&private->sch->dev));
+ VFIO_CCW_TRACE_EVENT(6, dev_name(&sch->dev));

memcpy(&private->irb, irb, sizeof(*irb));

@@ -376,7 +373,7 @@ static void fsm_irq(struct vfio_ccw_private *private,
static void fsm_open(struct vfio_ccw_private *private,
enum vfio_ccw_event event)
{
- struct subchannel *sch = private->sch;
+ struct subchannel *sch = to_subchannel(private->vdev.dev->parent);
int ret;

spin_lock_irq(sch->lock);
@@ -397,7 +394,7 @@ static void fsm_open(struct vfio_ccw_private *private,
static void fsm_close(struct vfio_ccw_private *private,
enum vfio_ccw_event event)
{
- struct subchannel *sch = private->sch;
+ struct subchannel *sch = to_subchannel(private->vdev.dev->parent);
int ret;

spin_lock_irq(sch->lock);
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index dc084883d872..79c50cb7dcb8 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -68,9 +68,9 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
return ret;

VFIO_CCW_MSG_EVENT(2, "sch %x.%x.%04x: create\n",
- private->sch->schid.cssid,
- private->sch->schid.ssid,
- private->sch->schid.sch_no);
+ sch->schid.cssid,
+ sch->schid.ssid,
+ sch->schid.sch_no);

ret = vfio_register_emulated_iommu_dev(&private->vdev);
if (ret)
@@ -107,9 +107,9 @@ static void vfio_ccw_mdev_remove(struct mdev_device *mdev)
struct vfio_ccw_private *private = dev_get_drvdata(&parent->dev);

VFIO_CCW_MSG_EVENT(2, "sch %x.%x.%04x: remove\n",
- private->sch->schid.cssid,
- private->sch->schid.ssid,
- private->sch->schid.sch_no);
+ sch->schid.cssid,
+ sch->schid.ssid,
+ sch->schid.sch_no);

vfio_unregister_group_dev(&private->vdev);

diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h
index 1f598d58d969..b28af2f63963 100644
--- a/drivers/s390/cio/vfio_ccw_private.h
+++ b/drivers/s390/cio/vfio_ccw_private.h
@@ -85,7 +85,6 @@ struct vfio_ccw_parent {
/**
* struct vfio_ccw_private
* @vdev: Embedded VFIO device
- * @sch: pointer to the subchannel
* @state: internal state of the device
* @completion: synchronization helper of the I/O completion
* @io_region: MMIO region to input/output I/O arguments/results
@@ -107,7 +106,6 @@ struct vfio_ccw_parent {
*/
struct vfio_ccw_private {
struct vfio_device vdev;
- struct subchannel *sch;
int state;
struct completion *completion;
struct ccw_io_region *io_region;
@@ -172,7 +170,10 @@ extern fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS];
static inline void vfio_ccw_fsm_event(struct vfio_ccw_private *private,
enum vfio_ccw_event event)
{
- trace_vfio_ccw_fsm_event(private->sch->schid, private->state, event);
+ struct subchannel *sch = to_subchannel(private->vdev.dev->parent);
+
+ if (sch)
+ trace_vfio_ccw_fsm_event(sch->schid, private->state, event);
vfio_ccw_jumptable[private->state][event](private, event);
}

--
2.34.1