From: Jike Song Date: Thu, 1 Dec 2016 05:20:05 +0000 (+0800) Subject: vfio: vfio_register_notifier: classify iommu notifier X-Git-Tag: v4.10-rc1~156^2~5 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=22195cbd3451a75abaf30651a61cf85c89061327;p=karo-tx-linux.git 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 Cc: Xiao Guangrong Reviewed-by: Kirti Wankhede Signed-off-by: Jike Song [aw: merge with commit 816ca69ea9c7 ("vfio: Fix handling of error returned by 'vfio_group_get_from_dev()'"), remove typedef] Signed-off-by: Alex Williamson --- diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 7b39313abf0d..6cc2a9ffac10 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -2008,59 +2008,44 @@ err_unpin_pages: } 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; } diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 51810a95416e..b88ad1e5e7ff 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -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); } diff --git a/include/linux/vfio.h b/include/linux/vfio.h index 15ff0421b423..0e5201f207d3 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -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); /*