diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index b9396424a9f9..0339adeee16b 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1330,6 +1330,12 @@ static int vfio_group_add_container_user(struct vfio_group *group) static const struct file_operations vfio_device_fops; +/* true if the vfio_device has open_device() called but not close_device() */ +static bool vfio_assert_device_open(struct vfio_device *device) +{ + return !WARN_ON_ONCE(!READ_ONCE(device->open_count)); +} + static int vfio_group_get_device_fd(struct vfio_group *group, char *buf) { struct vfio_device *device; @@ -1544,8 +1550,10 @@ static int vfio_device_fops_release(struct inode *inode, struct file *filep) struct vfio_device *device = filep->private_data; mutex_lock(&device->dev_set->lock); - if (!--device->open_count && device->ops->close_device) + vfio_assert_device_open(device); + if (device->open_count == 1 && device->ops->close_device) device->ops->close_device(device); + device->open_count--; mutex_unlock(&device->dev_set->lock); module_put(device->dev->driver->owner); @@ -2112,7 +2120,8 @@ int vfio_pin_pages(struct vfio_device *device, unsigned long *user_pfn, struct vfio_iommu_driver *driver; int ret; - if (!user_pfn || !phys_pfn || !npage) + if (!user_pfn || !phys_pfn || !npage || + !vfio_assert_device_open(device)) return -EINVAL; if (npage > VFIO_PIN_PAGES_MAX_ENTRIES) @@ -2121,10 +2130,6 @@ int vfio_pin_pages(struct vfio_device *device, unsigned long *user_pfn, if (group->dev_counter > 1) return -EINVAL; - ret = vfio_group_add_container_user(group); - if (ret) - return ret; - container = group->container; driver = container->iommu_driver; if (likely(driver && driver->ops->pin_pages)) @@ -2134,8 +2139,6 @@ int vfio_pin_pages(struct vfio_device *device, unsigned long *user_pfn, else ret = -ENOTTY; - vfio_group_try_dissolve_container(group); - return ret; } EXPORT_SYMBOL(vfio_pin_pages); @@ -2156,16 +2159,12 @@ int vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn, struct vfio_iommu_driver *driver; int ret; - if (!user_pfn || !npage) + if (!user_pfn || !npage || !vfio_assert_device_open(device)) return -EINVAL; if (npage > VFIO_PIN_PAGES_MAX_ENTRIES) return -E2BIG; - ret = vfio_group_add_container_user(device->group); - if (ret) - return ret; - container = device->group->container; driver = container->iommu_driver; if (likely(driver && driver->ops->unpin_pages)) @@ -2174,8 +2173,6 @@ int vfio_unpin_pages(struct vfio_device *device, unsigned long *user_pfn, else ret = -ENOTTY; - vfio_group_try_dissolve_container(device->group); - return ret; } EXPORT_SYMBOL(vfio_unpin_pages); @@ -2204,13 +2201,9 @@ int vfio_dma_rw(struct vfio_device *device, dma_addr_t user_iova, void *data, struct vfio_iommu_driver *driver; int ret = 0; - if (!data || len <= 0) + if (!data || len <= 0 || !vfio_assert_device_open(device)) return -EINVAL; - ret = vfio_group_add_container_user(device->group); - if (ret) - return ret; - container = device->group->container; driver = container->iommu_driver; @@ -2219,9 +2212,6 @@ int vfio_dma_rw(struct vfio_device *device, dma_addr_t user_iova, void *data, user_iova, data, len, write); else ret = -ENOTTY; - - vfio_group_try_dissolve_container(device->group); - return ret; } EXPORT_SYMBOL(vfio_dma_rw); @@ -2234,10 +2224,6 @@ static int vfio_register_iommu_notifier(struct vfio_group *group, struct vfio_iommu_driver *driver; int ret; - ret = vfio_group_add_container_user(group); - if (ret) - return -EINVAL; - container = group->container; driver = container->iommu_driver; if (likely(driver && driver->ops->register_notifier)) @@ -2245,9 +2231,6 @@ static int vfio_register_iommu_notifier(struct vfio_group *group, events, nb); else ret = -ENOTTY; - - vfio_group_try_dissolve_container(group); - return ret; } @@ -2258,10 +2241,6 @@ static int vfio_unregister_iommu_notifier(struct vfio_group *group, struct vfio_iommu_driver *driver; int ret; - ret = vfio_group_add_container_user(group); - if (ret) - return -EINVAL; - container = group->container; driver = container->iommu_driver; if (likely(driver && driver->ops->unregister_notifier)) @@ -2269,9 +2248,6 @@ static int vfio_unregister_iommu_notifier(struct vfio_group *group, nb); else ret = -ENOTTY; - - vfio_group_try_dissolve_container(group); - return ret; } @@ -2300,10 +2276,6 @@ static int vfio_register_group_notifier(struct vfio_group *group, if (*events) return -EINVAL; - ret = vfio_group_add_container_user(group); - if (ret) - return -EINVAL; - ret = blocking_notifier_chain_register(&group->notifier, nb); /* @@ -2313,25 +2285,6 @@ static int vfio_register_group_notifier(struct vfio_group *group, if (!ret && set_kvm && group->kvm) blocking_notifier_call_chain(&group->notifier, VFIO_GROUP_NOTIFY_SET_KVM, group->kvm); - - vfio_group_try_dissolve_container(group); - - return ret; -} - -static int vfio_unregister_group_notifier(struct vfio_group *group, - struct notifier_block *nb) -{ - int ret; - - ret = vfio_group_add_container_user(group); - if (ret) - return -EINVAL; - - ret = blocking_notifier_chain_unregister(&group->notifier, nb); - - vfio_group_try_dissolve_container(group); - return ret; } @@ -2342,7 +2295,8 @@ int vfio_register_notifier(struct vfio_device *device, struct vfio_group *group = device->group; int ret; - if (!nb || !events || (*events == 0)) + if (!nb || !events || (*events == 0) || + !vfio_assert_device_open(device)) return -EINVAL; switch (type) { @@ -2366,7 +2320,7 @@ int vfio_unregister_notifier(struct vfio_device *device, struct vfio_group *group = device->group; int ret; - if (!nb) + if (!nb || !vfio_assert_device_open(device)) return -EINVAL; switch (type) { @@ -2374,7 +2328,7 @@ int vfio_unregister_notifier(struct vfio_device *device, ret = vfio_unregister_iommu_notifier(group, nb); break; case VFIO_GROUP_NOTIFY: - ret = vfio_unregister_group_notifier(group, nb); + ret = blocking_notifier_chain_unregister(&group->notifier, nb); break; default: ret = -EINVAL;