diff options
| -rw-r--r-- | drivers/vfio/vfio.c | 21 |
1 files changed, 9 insertions, 12 deletions
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 4abb2e5e1965..e313fa030b91 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -69,7 +69,7 @@ struct vfio_unbound_dev { }; struct vfio_group { - struct kref kref; + refcount_t users; int minor; atomic_t container_users; struct iommu_group *iommu_group; @@ -377,7 +377,7 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group, if (!group) return ERR_PTR(-ENOMEM); - kref_init(&group->kref); + refcount_set(&group->users, 1); INIT_LIST_HEAD(&group->device_list); mutex_init(&group->device_lock); INIT_LIST_HEAD(&group->unbound_list); @@ -433,10 +433,10 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group, return group; } -/* called with vfio.group_lock held */ -static void vfio_group_release(struct kref *kref) +static void vfio_group_put(struct vfio_group *group) { - struct vfio_group *group = container_of(kref, struct vfio_group, kref); + if (!refcount_dec_and_mutex_lock(&group->users, &vfio.group_lock)) + return; /* * These data structures all have paired operations that can only be @@ -454,15 +454,9 @@ static void vfio_group_release(struct kref *kref) vfio_group_unlock_and_free(group); } -static void vfio_group_put(struct vfio_group *group) -{ - kref_put_mutex(&group->kref, vfio_group_release, &vfio.group_lock); -} - -/* Assume group_lock or group reference is held */ static void vfio_group_get(struct vfio_group *group) { - kref_get(&group->kref); + refcount_inc(&group->users); } static struct vfio_group *vfio_group_get_from_minor(int minor) @@ -1657,6 +1651,9 @@ struct vfio_group *vfio_group_get_external_user(struct file *filep) if (ret) return ERR_PTR(ret); + /* + * Since the caller holds the fget on the file group->users must be >= 1 + */ vfio_group_get(group); return group; |