vfio: vfio_register_notifier: classify iommu notifier

Currently vfio_register_notifier assumes that there is only one
notifier chain, which is in vfio_iommu. However, the user might
also be interested in events other than vfio_iommu, for example,
vfio_group. Refactor vfio_{un}register_notifier implementation
to make it feasible.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Jike Song <jike.song@intel.com>
[aw: merge with commit 816ca69ea9c7 ("vfio: Fix handling of error returned by 'vfio_group_get_from_dev()'"), remove typedef]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Jike Song 2016-12-01 13:20:05 +08:00 committed by Alex Williamson
parent d256459fae
commit 22195cbd34
3 changed files with 78 additions and 27 deletions

View File

@ -2008,59 +2008,44 @@ int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage)
}
EXPORT_SYMBOL(vfio_unpin_pages);
int vfio_register_notifier(struct device *dev, struct notifier_block *nb)
static int vfio_register_iommu_notifier(struct vfio_group *group,
unsigned long *events,
struct notifier_block *nb)
{
struct vfio_container *container;
struct vfio_group *group;
struct vfio_iommu_driver *driver;
int ret;
if (!dev || !nb)
return -EINVAL;
group = vfio_group_get_from_dev(dev);
if (!group)
return -ENODEV;
ret = vfio_group_add_container_user(group);
if (ret)
goto err_register_nb;
return -EINVAL;
container = group->container;
down_read(&container->group_lock);
driver = container->iommu_driver;
if (likely(driver && driver->ops->register_notifier))
ret = driver->ops->register_notifier(container->iommu_data, nb);
ret = driver->ops->register_notifier(container->iommu_data,
events, nb);
else
ret = -ENOTTY;
up_read(&container->group_lock);
vfio_group_try_dissolve_container(group);
err_register_nb:
vfio_group_put(group);
return ret;
}
EXPORT_SYMBOL(vfio_register_notifier);
int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
static int vfio_unregister_iommu_notifier(struct vfio_group *group,
struct notifier_block *nb)
{
struct vfio_container *container;
struct vfio_group *group;
struct vfio_iommu_driver *driver;
int ret;
if (!dev || !nb)
return -EINVAL;
group = vfio_group_get_from_dev(dev);
if (!group)
return -ENODEV;
ret = vfio_group_add_container_user(group);
if (ret)
goto err_unregister_nb;
return -EINVAL;
container = group->container;
down_read(&container->group_lock);
@ -2075,7 +2060,56 @@ int vfio_unregister_notifier(struct device *dev, struct notifier_block *nb)
up_read(&container->group_lock);
vfio_group_try_dissolve_container(group);
err_unregister_nb:
return ret;
}
int vfio_register_notifier(struct device *dev, enum vfio_notify_type type,
unsigned long *events, struct notifier_block *nb)
{
struct vfio_group *group;
int ret;
if (!dev || !nb || !events || (*events == 0))
return -EINVAL;
group = vfio_group_get_from_dev(dev);
if (!group)
return -ENODEV;
switch (type) {
case VFIO_IOMMU_NOTIFY:
ret = vfio_register_iommu_notifier(group, events, nb);
break;
default:
ret = -EINVAL;
}
vfio_group_put(group);
return ret;
}
EXPORT_SYMBOL(vfio_register_notifier);
int vfio_unregister_notifier(struct device *dev, enum vfio_notify_type type,
struct notifier_block *nb)
{
struct vfio_group *group;
int ret;
if (!dev || !nb)
return -EINVAL;
group = vfio_group_get_from_dev(dev);
if (!group)
return -ENODEV;
switch (type) {
case VFIO_IOMMU_NOTIFY:
ret = vfio_unregister_iommu_notifier(group, nb);
break;
default:
ret = -EINVAL;
}
vfio_group_put(group);
return ret;
}

View File

@ -1584,10 +1584,18 @@ static long vfio_iommu_type1_ioctl(void *iommu_data,
}
static int vfio_iommu_type1_register_notifier(void *iommu_data,
unsigned long *events,
struct notifier_block *nb)
{
struct vfio_iommu *iommu = iommu_data;
/* clear known events */
*events &= ~VFIO_IOMMU_NOTIFY_DMA_UNMAP;
/* refuse to register if still events remaining */
if (*events)
return -EINVAL;
return blocking_notifier_chain_register(&iommu->notifier, nb);
}

View File

@ -81,6 +81,7 @@ struct vfio_iommu_driver_ops {
int (*unpin_pages)(void *iommu_data,
unsigned long *user_pfn, int npage);
int (*register_notifier)(void *iommu_data,
unsigned long *events,
struct notifier_block *nb);
int (*unregister_notifier)(void *iommu_data,
struct notifier_block *nb);
@ -107,12 +108,20 @@ extern int vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn,
int npage);
#define VFIO_IOMMU_NOTIFY_DMA_UNMAP (1)
/* each type has independent events */
enum vfio_notify_type {
VFIO_IOMMU_NOTIFY = 0,
};
/* events for VFIO_IOMMU_NOTIFY */
#define VFIO_IOMMU_NOTIFY_DMA_UNMAP BIT(0)
extern int vfio_register_notifier(struct device *dev,
enum vfio_notify_type type,
unsigned long *required_events,
struct notifier_block *nb);
extern int vfio_unregister_notifier(struct device *dev,
enum vfio_notify_type type,
struct notifier_block *nb);
/*