[libvirt] [PATCH v3 2/6] vfio/mdev: Add "aggregation" attribute for supported mdev type

For supported mdev driver to create aggregated device, this creates new "aggregation" attribute for target type, which will show maximum number of instance resources that can be aggregated. Cc: Kirti Wankhede <kwankhede(a)nvidia.com&gt; Cc: Alex Williamson <alex.williamson(a)redhat.com&gt; Cc: Kevin Tian <kevin.tian(a)intel.com&gt; Cc: Cornelia Huck <cohuck(a)redhat.com&gt; Signed-off-by: Zhenyu Wang <zhenyuw(a)linux.intel.com&gt; --- drivers/vfio/mdev/mdev_core.c | 19 +++++++++++++++++++ drivers/vfio/mdev/mdev_private.h | 2 ++ drivers/vfio/mdev/mdev_sysfs.c | 22 ++++++++++++++++++++++ include/linux/mdev.h | 8 ++++++++ 4 files changed, 51 insertions(+) diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c index 545c52ec7618..8f8bbb72e5d9 100644 --- a/drivers/vfio/mdev/mdev_core.c +++ b/drivers/vfio/mdev/mdev_core.c @@ -161,6 +161,25 @@ static int mdev_device_remove_cb(struct device *dev, void *data) return mdev_device_remove(dev, data ? *(bool *)data : true); } +int mdev_max_aggregated_instances(struct kobject *kobj, struct device *dev, + unsigned int *m) +{ + struct mdev_parent *parent; + struct mdev_type *type = to_mdev_type(kobj); + int ret; + + parent = mdev_get_parent(type->parent); + if (!parent) + return -EINVAL; + + if (parent->ops->max_aggregated_instances) { + ret = parent->ops->max_aggregated_instances(kobj, dev, m); + } else + ret = -EINVAL; + mdev_put_parent(parent); + return ret; +} + /* * mdev_register_device : Register a device * @dev: device structure representing parent device. diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h index e90d295d3927..f1289db75884 100644 --- a/drivers/vfio/mdev/mdev_private.h +++ b/drivers/vfio/mdev/mdev_private.h @@ -63,4 +63,6 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid, unsigned int instances); int mdev_device_remove(struct device *dev, bool force_remove); +int mdev_max_aggregated_instances(struct kobject *kobj, struct device *dev, + unsigned int *m); #endif /* MDEV_PRIVATE_H */ diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c index aefed0c8891b..a329d6ab6cb9 100644 --- a/drivers/vfio/mdev/mdev_sysfs.c +++ b/drivers/vfio/mdev/mdev_sysfs.c @@ -103,6 +103,18 @@ static ssize_t create_store(struct kobject *kobj, struct device *dev, MDEV_TYPE_ATTR_WO(create); +static ssize_t +aggregation_show(struct kobject *kobj, struct device *dev, char *buf) +{ + unsigned int m; + + if (mdev_max_aggregated_instances(kobj, dev, &m)) + return sprintf(buf, "1\n"); + else + return sprintf(buf, "%u\n", m); +} +MDEV_TYPE_ATTR_RO(aggregation); + static void mdev_type_release(struct kobject *kobj) { struct mdev_type *type = to_mdev_type(kobj); @@ -145,6 +157,14 @@ struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent, if (ret) goto attr_create_failed; + if (parent->ops->create_with_instances && + parent->ops->max_aggregated_instances) { + ret = sysfs_create_file(&type->kobj, + &mdev_type_attr_aggregation.attr); + if (ret) + goto attr_aggregate_failed; + } + type->devices_kobj = kobject_create_and_add("devices", &type->kobj); if (!type->devices_kobj) { ret = -ENOMEM; @@ -165,6 +185,8 @@ struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent, attrs_failed: kobject_put(type->devices_kobj); attr_devices_failed: + sysfs_remove_file(&type->kobj, &mdev_type_attr_aggregation.attr); +attr_aggregate_failed: sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr); attr_create_failed: kobject_del(&type->kobj); diff --git a/include/linux/mdev.h b/include/linux/mdev.h index c12c0bfc5598..66cfdb0bf0d6 100644 --- a/include/linux/mdev.h +++ b/include/linux/mdev.h @@ -39,6 +39,11 @@ struct mdev_device; * that is being created * @instances: number of instances to aggregate * Returns integer: success (0) or error (< 0) + * @max_aggregated_instances: Return max number for aggregated resources + * @kobj: kobject of type + * @dev: mdev parent device for target type + * @max: return max number of instances which can aggregate + * Returns integer: success (0) or error (< 0) * @remove: Called to free resources in parent device's driver for a * a mediated device. It is mandatory to provide 'remove' * ops. @@ -82,6 +87,9 @@ struct mdev_parent_ops { int (*create_with_instances)(struct kobject *kobj, struct mdev_device *mdev, unsigned int instances); + int (*max_aggregated_instances)(struct kobject *kobj, + struct device *dev, + unsigned int *max); int (*remove)(struct mdev_device *mdev); int (*open)(struct mdev_device *mdev); void (*release)(struct mdev_device *mdev); -- 2.19.1