diff options
| -rw-r--r-- | drivers/vfio/vfio.c | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 21eddd9e0f26..073788e50e4b 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -24,6 +24,7 @@ #include <linux/list.h> #include <linux/module.h> #include <linux/mutex.h> +#include <linux/rwsem.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/string.h> @@ -57,7 +58,7 @@ struct vfio_iommu_driver { struct vfio_container { struct kref kref; struct list_head group_list; - struct mutex group_lock; + struct rw_semaphore group_lock; struct vfio_iommu_driver *iommu_driver; void *iommu_data; }; @@ -738,7 +739,7 @@ static long vfio_ioctl_check_extension(struct vfio_container *container, return ret; } -/* hold container->group_lock */ +/* hold write lock on container->group_lock */ static int __vfio_container_attach_groups(struct vfio_container *container, struct vfio_iommu_driver *driver, void *data) @@ -769,7 +770,7 @@ static long vfio_ioctl_set_iommu(struct vfio_container *container, struct vfio_iommu_driver *driver; long ret = -ENODEV; - mutex_lock(&container->group_lock); + down_write(&container->group_lock); /* * The container is designed to be an unprivileged interface while @@ -780,7 +781,7 @@ static long vfio_ioctl_set_iommu(struct vfio_container *container, * the container is deprivileged and returns to an unset state. */ if (list_empty(&container->group_list) || container->iommu_driver) { - mutex_unlock(&container->group_lock); + up_write(&container->group_lock); return -EINVAL; } @@ -827,7 +828,7 @@ static long vfio_ioctl_set_iommu(struct vfio_container *container, mutex_unlock(&vfio.iommu_drivers_lock); skip_drivers_unlock: - mutex_unlock(&container->group_lock); + up_write(&container->group_lock); return ret; } @@ -882,7 +883,7 @@ static int vfio_fops_open(struct inode *inode, struct file *filep) return -ENOMEM; INIT_LIST_HEAD(&container->group_list); - mutex_init(&container->group_lock); + init_rwsem(&container->group_lock); kref_init(&container->kref); filep->private_data = container; @@ -961,7 +962,7 @@ static void __vfio_group_unset_container(struct vfio_group *group) struct vfio_container *container = group->container; struct vfio_iommu_driver *driver; - mutex_lock(&container->group_lock); + down_write(&container->group_lock); driver = container->iommu_driver; if (driver) @@ -979,7 +980,7 @@ static void __vfio_group_unset_container(struct vfio_group *group) container->iommu_data = NULL; } - mutex_unlock(&container->group_lock); + up_write(&container->group_lock); vfio_container_put(container); } @@ -1039,7 +1040,7 @@ static int vfio_group_set_container(struct vfio_group *group, int container_fd) container = f.file->private_data; WARN_ON(!container); /* fget ensures we don't race vfio_release */ - mutex_lock(&container->group_lock); + down_write(&container->group_lock); driver = container->iommu_driver; if (driver) { @@ -1057,7 +1058,7 @@ static int vfio_group_set_container(struct vfio_group *group, int container_fd) atomic_inc(&group->container_users); unlock_out: - mutex_unlock(&container->group_lock); + up_write(&container->group_lock); fdput(f); return ret; } |