[RFC PATCH 2/3] vfio: ccw: introduce channel path irq

Dong Jia Shi
2018-01-11T03:04:20Z

This introduces a new irq for vfio-ccw to provide channel path
related event for userland.

Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
---
drivers/s390/cio/vfio_ccw_ops.c | 29 +++++++++++++++++++++--------
drivers/s390/cio/vfio_ccw_private.h | 2 ++
include/uapi/linux/vfio.h | 1 +
3 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 9528fce2e7d9..972cfc8834fc 100644
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -275,17 +275,20 @@ static int vfio_ccw_mdev_get_region_info(struct vfio_region_info *info,

static int vfio_ccw_mdev_get_irq_info(struct vfio_irq_info *info)
{
- if (info->index != VFIO_CCW_IO_IRQ_INDEX)
+ switch (info->index) {
+ case VFIO_CCW_IO_IRQ_INDEX:
+ case VFIO_CCW_CHP_IRQ_INDEX:
+ info->count = 1;
+ info->flags = VFIO_IRQ_INFO_EVENTFD;
+ return 0;
+ default:
return -EINVAL;
-
- info->count = 1;
- info->flags = VFIO_IRQ_INFO_EVENTFD;
-
- return 0;
+ }
}

static int vfio_ccw_mdev_set_irqs(struct mdev_device *mdev,
uint32_t flags,
+ unsigned index,
void __user *data)
{
struct vfio_ccw_private *private;
@@ -295,7 +298,17 @@ static int vfio_ccw_mdev_set_irqs(struct mdev_device *mdev,
return -EINVAL;

private = dev_get_drvdata(mdev_parent_dev(mdev));
- ctx = &private->io_trigger;
+
+ switch (index) {
+ case VFIO_CCW_IO_IRQ_INDEX:
+ ctx = &private->io_trigger;
+ break;
+ case VFIO_CCW_CHP_IRQ_INDEX:
+ ctx = &private->chp_trigger;
+ break;
+ default:
+ return -EINVAL;
+ }

switch (flags & VFIO_IRQ_SET_DATA_TYPE_MASK) {
case VFIO_IRQ_SET_DATA_NONE:
@@ -433,7 +446,7 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev,
return ret;

data = (void __user *)(arg + minsz);
- return vfio_ccw_mdev_set_irqs(mdev, hdr.flags, data);
+ return vfio_ccw_mdev_set_irqs(mdev, hdr.flags, hdr.index, data);
}
case VFIO_DEVICE_RESET:
return vfio_ccw_mdev_reset(mdev);
diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h
index 460c8b90d834..da86f82dd7b9 100644
--- a/drivers/s390/cio/vfio_ccw_private.h
+++ b/drivers/s390/cio/vfio_ccw_private.h
@@ -33,6 +33,7 @@
* @irb: irb info received from interrupt
* @scsw: scsw info
* @io_trigger: eventfd ctx for signaling userspace I/O results
+ * @chp_trigger: eventfd ctx for signaling userspace chp event
* @io_work: work for deferral process of I/O handling
*/
struct vfio_ccw_private {
@@ -50,6 +51,7 @@ struct vfio_ccw_private {
union scsw scsw;

struct eventfd_ctx *io_trigger;
+ struct eventfd_ctx *chp_trigger;
struct work_struct io_work;
} __aligned(8);

diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index c60244debf71..179a7492d53a 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -463,6 +463,7 @@ enum {

enum {
VFIO_CCW_IO_IRQ_INDEX,
+ VFIO_CCW_CHP_IRQ_INDEX,
VFIO_CCW_NUM_IRQS
};

--
2.13.5