[libvirt] [PATCH v2 1/4] vfio/mdev: Add new instances parameter for mdev create

For special mdev type which can aggregate instances for mdev device, this extends mdev create interface by allowing extra "instances=xxx" parameter, which is passed to mdev device model to be able to create arbitrary bundled number of instances for target mdev device. v2: create new create_with_instances operator for vendor driver 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; Signed-off-by: Zhenyu Wang <zhenyuw(a)linux.intel.com&gt; --- drivers/vfio/mdev/mdev_core.c | 18 +++++++++++++---- drivers/vfio/mdev/mdev_private.h | 5 ++++- drivers/vfio/mdev/mdev_sysfs.c | 34 ++++++++++++++++++++++++++------ include/linux/mdev.h | 10 ++++++++++ 4 files changed, 56 insertions(+), 11 deletions(-) diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c index 0212f0ee8aea..e69db302a4f2 100644 --- a/drivers/vfio/mdev/mdev_core.c +++ b/drivers/vfio/mdev/mdev_core.c @@ -104,12 +104,16 @@ static inline void mdev_put_parent(struct mdev_parent *parent) } static int mdev_device_create_ops(struct kobject *kobj, - struct mdev_device *mdev) + struct mdev_device *mdev, + unsigned int instances) { struct mdev_parent *parent = mdev->parent; int ret; - ret = parent->ops->create(kobj, mdev); + if (instances > 1) + ret = parent->ops->create_with_instances(kobj, mdev, instances); + else + ret = parent->ops->create(kobj, mdev); if (ret) return ret; @@ -276,7 +280,8 @@ static void mdev_device_release(struct device *dev) kfree(mdev); } -int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid) +int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid, + unsigned int instances) { int ret; struct mdev_device *mdev, *tmp; @@ -287,6 +292,11 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid) if (!parent) return -EINVAL; + if (instances > 1 && !parent->ops->create_with_instances) { + ret = -EINVAL; + goto mdev_fail; + } + mutex_lock(&mdev_list_lock); /* Check for duplicate */ @@ -323,7 +333,7 @@ int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid) goto mdev_fail; } - ret = mdev_device_create_ops(kobj, mdev); + ret = mdev_device_create_ops(kobj, mdev, instances); if (ret) goto create_fail; diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h index b5819b7d7ef7..c9d3fe04e273 100644 --- a/drivers/vfio/mdev/mdev_private.h +++ b/drivers/vfio/mdev/mdev_private.h @@ -52,13 +52,16 @@ struct mdev_type { #define to_mdev_type(_kobj) \ container_of(_kobj, struct mdev_type, kobj) +#define MDEV_CREATE_OPT_LEN 32 + int parent_create_sysfs_files(struct mdev_parent *parent); void parent_remove_sysfs_files(struct mdev_parent *parent); int mdev_create_sysfs_files(struct device *dev, struct mdev_type *type); void mdev_remove_sysfs_files(struct device *dev, struct mdev_type *type); -int mdev_device_create(struct kobject *kobj, struct device *dev, uuid_le uuid); +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); #endif /* MDEV_PRIVATE_H */ diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c index 249472f05509..a06e5b7c69d3 100644 --- a/drivers/vfio/mdev/mdev_sysfs.c +++ b/drivers/vfio/mdev/mdev_sysfs.c @@ -54,11 +54,15 @@ static const struct sysfs_ops mdev_type_sysfs_ops = { static ssize_t create_store(struct kobject *kobj, struct device *dev, const char *buf, size_t count) { - char *str; + char *str, *opt = NULL; uuid_le uuid; int ret; + unsigned int instances = 1; - if ((count < UUID_STRING_LEN) || (count > UUID_STRING_LEN + 1)) + if (count < UUID_STRING_LEN) + return -EINVAL; + + if (count > UUID_STRING_LEN + 1 + MDEV_CREATE_OPT_LEN) return -EINVAL; str = kstrndup(buf, count, GFP_KERNEL); @@ -66,13 +70,31 @@ static ssize_t create_store(struct kobject *kobj, struct device *dev, return -ENOMEM; ret = uuid_le_to_bin(str, &uuid); - kfree(str); - if (ret) + if (ret) { + kfree(str); return ret; + } - ret = mdev_device_create(kobj, dev, uuid); - if (ret) + if (count > UUID_STRING_LEN + 1) { + opt = str + UUID_STRING_LEN; + if (*opt++ != ',' || + strncmp(opt, "instances=", 10)) { + kfree(str); + return -EINVAL; + } + opt += 10; + if (kstrtouint(opt, 10, &instances)) { + kfree(str); + return -EINVAL; + } + } + + ret = mdev_device_create(kobj, dev, uuid, instances); + if (ret) { + kfree(str); return ret; + } + kfree(str); return count; } diff --git a/include/linux/mdev.h b/include/linux/mdev.h index b6e048e1045f..cfb702600f95 100644 --- a/include/linux/mdev.h +++ b/include/linux/mdev.h @@ -30,6 +30,13 @@ struct mdev_device; * @kobj: kobject of type for which 'create' is called. * @mdev: mdev_device structure on of mediated device * that is being created + * @create_with_instances: Allocate aggregated instances' resources in parent device's + * driver for a particular mediated device. It is optional + * if doesn't support aggregated resources. + * @kobj: kobject of type for which 'create' is called. + * @mdev: mdev_device structure on of mediated device + * that is being created + * @instances: number of instances to 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' @@ -71,6 +78,9 @@ struct mdev_parent_ops { struct attribute_group **supported_type_groups; int (*create)(struct kobject *kobj, struct mdev_device *mdev); + int (*create_with_instances)(struct kobject *kobj, + struct mdev_device *mdev, + unsigned int instances); int (*remove)(struct mdev_device *mdev); int (*open)(struct mdev_device *mdev); void (*release)(struct mdev_device *mdev); -- 2.18.0