diff options
Diffstat (limited to 'drivers/s390/cio')
-rw-r--r-- | drivers/s390/cio/vfio_ccw_drv.c | 12 | ||||
-rw-r--r-- | drivers/s390/cio/vfio_ccw_ops.c | 92 | ||||
-rw-r--r-- | drivers/s390/cio/vfio_ccw_private.h | 11 |
3 files changed, 57 insertions, 58 deletions
diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c index 86d9e428357b..7f5402fe857a 100644 --- a/drivers/s390/cio/vfio_ccw_drv.c +++ b/drivers/s390/cio/vfio_ccw_drv.c @@ -12,7 +12,6 @@ #include <linux/module.h> #include <linux/init.h> -#include <linux/device.h> #include <linux/slab.h> #include <linux/mdev.h> @@ -142,7 +141,6 @@ static struct vfio_ccw_private *vfio_ccw_alloc_private(struct subchannel *sch) INIT_LIST_HEAD(&private->crw); INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo); INIT_WORK(&private->crw_work, vfio_ccw_crw_todo); - atomic_set(&private->avail, 1); private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct ccw1), GFP_KERNEL); @@ -203,7 +201,6 @@ static void vfio_ccw_free_private(struct vfio_ccw_private *private) mutex_destroy(&private->io_mutex); kfree(private); } - static int vfio_ccw_sch_probe(struct subchannel *sch) { struct pmcw *pmcw = &sch->schib.pmcw; @@ -222,7 +219,12 @@ static int vfio_ccw_sch_probe(struct subchannel *sch) dev_set_drvdata(&sch->dev, private); - ret = mdev_register_device(&sch->dev, &vfio_ccw_mdev_driver); + private->mdev_type.sysfs_name = "io"; + private->mdev_type.pretty_name = "I/O subchannel (Non-QDIO)"; + private->mdev_types[0] = &private->mdev_type; + ret = mdev_register_parent(&private->parent, &sch->dev, + &vfio_ccw_mdev_driver, + private->mdev_types, 1); if (ret) goto out_free; @@ -241,7 +243,7 @@ static void vfio_ccw_sch_remove(struct subchannel *sch) { struct vfio_ccw_private *private = dev_get_drvdata(&sch->dev); - mdev_unregister_device(&sch->dev); + mdev_unregister_parent(&private->parent); dev_set_drvdata(&sch->dev, NULL); diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c index 4a806a2273b5..6ae4d012d800 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -11,7 +11,6 @@ */ #include <linux/vfio.h> -#include <linux/mdev.h> #include <linux/nospec.h> #include <linux/slab.h> @@ -45,47 +44,14 @@ static void vfio_ccw_dma_unmap(struct vfio_device *vdev, u64 iova, u64 length) vfio_ccw_mdev_reset(private); } -static ssize_t name_show(struct mdev_type *mtype, - struct mdev_type_attribute *attr, char *buf) -{ - return sprintf(buf, "I/O subchannel (Non-QDIO)\n"); -} -static MDEV_TYPE_ATTR_RO(name); - -static ssize_t device_api_show(struct mdev_type *mtype, - struct mdev_type_attribute *attr, char *buf) -{ - return sprintf(buf, "%s\n", VFIO_DEVICE_API_CCW_STRING); -} -static MDEV_TYPE_ATTR_RO(device_api); - -static ssize_t available_instances_show(struct mdev_type *mtype, - struct mdev_type_attribute *attr, - char *buf) +static int vfio_ccw_mdev_init_dev(struct vfio_device *vdev) { struct vfio_ccw_private *private = - dev_get_drvdata(mtype_get_parent_dev(mtype)); + container_of(vdev, struct vfio_ccw_private, vdev); - return sprintf(buf, "%d\n", atomic_read(&private->avail)); + init_completion(&private->release_comp); + return 0; } -static 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, -}; - -static struct attribute_group *mdev_type_groups[] = { - &mdev_type_group, - NULL, -}; static int vfio_ccw_mdev_probe(struct mdev_device *mdev) { @@ -95,12 +61,9 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev) if (private->state == VFIO_CCW_STATE_NOT_OPER) return -ENODEV; - if (atomic_dec_if_positive(&private->avail) < 0) - return -EPERM; - - memset(&private->vdev, 0, sizeof(private->vdev)); - vfio_init_group_dev(&private->vdev, &mdev->dev, - &vfio_ccw_dev_ops); + ret = vfio_init_device(&private->vdev, &mdev->dev, &vfio_ccw_dev_ops); + if (ret) + return ret; VFIO_CCW_MSG_EVENT(2, "sch %x.%x.%04x: create\n", private->sch->schid.cssid, @@ -109,16 +72,32 @@ static int vfio_ccw_mdev_probe(struct mdev_device *mdev) ret = vfio_register_emulated_iommu_dev(&private->vdev); if (ret) - goto err_atomic; + goto err_put_vdev; dev_set_drvdata(&mdev->dev, private); return 0; -err_atomic: - vfio_uninit_group_dev(&private->vdev); - atomic_inc(&private->avail); +err_put_vdev: + vfio_put_device(&private->vdev); return ret; } +static void vfio_ccw_mdev_release_dev(struct vfio_device *vdev) +{ + struct vfio_ccw_private *private = + container_of(vdev, struct vfio_ccw_private, vdev); + + /* + * We cannot free vfio_ccw_private here because it includes + * parent info which must be free'ed by css driver. + * + * Use a workaround by memset'ing the core device part and + * then notifying the remove path that all active references + * to this device have been released. + */ + memset(vdev, 0, sizeof(*vdev)); + complete(&private->release_comp); +} + static void vfio_ccw_mdev_remove(struct mdev_device *mdev) { struct vfio_ccw_private *private = dev_get_drvdata(mdev->dev.parent); @@ -130,8 +109,16 @@ static void vfio_ccw_mdev_remove(struct mdev_device *mdev) vfio_unregister_group_dev(&private->vdev); - vfio_uninit_group_dev(&private->vdev); - atomic_inc(&private->avail); + vfio_put_device(&private->vdev); + /* + * Wait for all active references on mdev are released so it + * is safe to defer kfree() to a later point. + * + * TODO: the clean fix is to split parent/mdev info from ccw + * private structure so each can be managed in its own life + * cycle. + */ + wait_for_completion(&private->release_comp); } static int vfio_ccw_mdev_open_device(struct vfio_device *vdev) @@ -592,6 +579,8 @@ static void vfio_ccw_mdev_request(struct vfio_device *vdev, unsigned int count) } static const struct vfio_device_ops vfio_ccw_dev_ops = { + .init = vfio_ccw_mdev_init_dev, + .release = vfio_ccw_mdev_release_dev, .open_device = vfio_ccw_mdev_open_device, .close_device = vfio_ccw_mdev_close_device, .read = vfio_ccw_mdev_read, @@ -602,6 +591,8 @@ static const struct vfio_device_ops vfio_ccw_dev_ops = { }; struct mdev_driver vfio_ccw_mdev_driver = { + .device_api = VFIO_DEVICE_API_CCW_STRING, + .max_instances = 1, .driver = { .name = "vfio_ccw_mdev", .owner = THIS_MODULE, @@ -609,5 +600,4 @@ struct mdev_driver vfio_ccw_mdev_driver = { }, .probe = vfio_ccw_mdev_probe, .remove = vfio_ccw_mdev_remove, - .supported_type_groups = mdev_type_groups, }; diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h index cd24b7fada91..bd5fb81456af 100644 --- a/drivers/s390/cio/vfio_ccw_private.h +++ b/drivers/s390/cio/vfio_ccw_private.h @@ -18,6 +18,7 @@ #include <linux/workqueue.h> #include <linux/vfio_ccw.h> #include <linux/vfio.h> +#include <linux/mdev.h> #include <asm/crw.h> #include <asm/debug.h> @@ -72,7 +73,6 @@ struct vfio_ccw_crw { * @sch: pointer to the subchannel * @state: internal state of the device * @completion: synchronization helper of the I/O completion - * @avail: available for creating a mediated device * @io_region: MMIO region to input/output I/O arguments/results * @io_mutex: protect against concurrent update of I/O regions * @region: additional regions for other subchannel operations @@ -88,13 +88,14 @@ struct vfio_ccw_crw { * @req_trigger: eventfd ctx for signaling userspace to return device * @io_work: work for deferral process of I/O handling * @crw_work: work for deferral process of CRW handling + * @release_comp: synchronization helper for vfio device release + * @parent: parent data structures for mdevs created */ struct vfio_ccw_private { struct vfio_device vdev; struct subchannel *sch; int state; struct completion *completion; - atomic_t avail; struct ccw_io_region *io_region; struct mutex io_mutex; struct vfio_ccw_region *region; @@ -113,6 +114,12 @@ struct vfio_ccw_private { struct eventfd_ctx *req_trigger; struct work_struct io_work; struct work_struct crw_work; + + struct completion release_comp; + + struct mdev_parent parent; + struct mdev_type mdev_type; + struct mdev_type *mdev_types[1]; } __aligned(8); int vfio_ccw_sch_quiesce(struct subchannel *sch); |