diff options
author | Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> | 2017-03-17 04:17:33 +0100 |
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committer | Cornelia Huck <cornelia.huck@de.ibm.com> | 2017-03-31 12:55:06 +0200 |
commit | 84cd8fc48478b5e67b3f1600717299e11430a67e (patch) | |
tree | a6654495414878b703656bb97c0557746d4b00ed /drivers/s390/cio/vfio_ccw_ops.c | |
parent | 0a19e61e6d4c6192077ead760ba0a2d350987d4c (diff) | |
download | linux-84cd8fc48478b5e67b3f1600717299e11430a67e.tar.bz2 |
vfio: ccw: register vfio_ccw to the mediated device framework
To make vfio support subchannel devices, we need to leverage the
mediated device framework to create a mediated device for the
subchannel device.
This registers the subchannel device to the mediated device
framework during probe to enable mediated device creation.
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-7-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Diffstat (limited to 'drivers/s390/cio/vfio_ccw_ops.c')
-rw-r--r-- | drivers/s390/cio/vfio_ccw_ops.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c new file mode 100644 index 000000000000..b8a2fed58f02 --- /dev/null +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -0,0 +1,147 @@ +/* + * Physical device callbacks for vfio_ccw + * + * Copyright IBM Corp. 2017 + * + * Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> + * Xiao Feng Ren <renxiaof@linux.vnet.ibm.com> + */ + +#include <linux/vfio.h> +#include <linux/mdev.h> + +#include "vfio_ccw_private.h" + +static int vfio_ccw_mdev_notifier(struct notifier_block *nb, + unsigned long action, + void *data) +{ + struct vfio_ccw_private *private = + container_of(nb, struct vfio_ccw_private, nb); + + if (!private) + return NOTIFY_STOP; + + /* + * TODO: + * Vendor drivers MUST unpin pages in response to an + * invalidation. + */ + if (action == VFIO_IOMMU_NOTIFY_DMA_UNMAP) + return NOTIFY_BAD; + + return NOTIFY_DONE; +} + +static ssize_t name_show(struct kobject *kobj, struct device *dev, char *buf) +{ + return sprintf(buf, "I/O subchannel (Non-QDIO)\n"); +} +MDEV_TYPE_ATTR_RO(name); + +static ssize_t device_api_show(struct kobject *kobj, struct device *dev, + char *buf) +{ + return sprintf(buf, "%s\n", VFIO_DEVICE_API_CCW_STRING); +} +MDEV_TYPE_ATTR_RO(device_api); + +static ssize_t available_instances_show(struct kobject *kobj, + struct device *dev, char *buf) +{ + struct vfio_ccw_private *private = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", atomic_read(&private->avail)); +} +MDEV_TYPE_ATTR_RO(available_instances); + +static struct attribute *mdev_types_attrs[] = { + &mdev_type_attr_name.attr, + &mdev_type_attr_device_api.attr, + &mdev_type_attr_available_instances.attr, + NULL, +}; + +static struct attribute_group mdev_type_group = { + .name = "io", + .attrs = mdev_types_attrs, +}; + +struct attribute_group *mdev_type_groups[] = { + &mdev_type_group, + NULL, +}; + +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 (atomic_dec_if_positive(&private->avail) < 0) + return -EPERM; + + private->mdev = mdev; + + return 0; +} + +static int vfio_ccw_mdev_remove(struct mdev_device *mdev) +{ + struct vfio_ccw_private *private; + struct subchannel *sch; + int ret; + + private = dev_get_drvdata(mdev_parent_dev(mdev)); + sch = private->sch; + ret = vfio_ccw_sch_quiesce(sch); + if (ret) + return ret; + ret = cio_enable_subchannel(sch, (u32)(unsigned long)sch); + if (ret) + return ret; + + private->mdev = NULL; + atomic_inc(&private->avail); + + return 0; +} + +static int vfio_ccw_mdev_open(struct mdev_device *mdev) +{ + struct vfio_ccw_private *private = + dev_get_drvdata(mdev_parent_dev(mdev)); + unsigned long events = VFIO_IOMMU_NOTIFY_DMA_UNMAP; + + private->nb.notifier_call = vfio_ccw_mdev_notifier; + + return vfio_register_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, + &events, &private->nb); +} + +void vfio_ccw_mdev_release(struct mdev_device *mdev) +{ + struct vfio_ccw_private *private = + dev_get_drvdata(mdev_parent_dev(mdev)); + + vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, + &private->nb); +} + +static const struct mdev_parent_ops vfio_ccw_mdev_ops = { + .owner = THIS_MODULE, + .supported_type_groups = mdev_type_groups, + .create = vfio_ccw_mdev_create, + .remove = vfio_ccw_mdev_remove, + .open = vfio_ccw_mdev_open, + .release = vfio_ccw_mdev_release, +}; + +int vfio_ccw_mdev_reg(struct subchannel *sch) +{ + return mdev_register_device(&sch->dev, &vfio_ccw_mdev_ops); +} + +void vfio_ccw_mdev_unreg(struct subchannel *sch) +{ + mdev_unregister_device(&sch->dev); +} |