vfio: Create wrappers for group register/unregister

This avoids decoding group fields in the common functions used by
vfio_device registration, and prepares for further moving the vfio group
specific code into separate file.

Link: https://lore.kernel.org/r/20221201145535.589687-4-yi.l.liu@intel.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Lixiao Yang <lixiao.yang@intel.com>
Tested-by: Yu He <yu.he@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
index 87d9a1670a2fbd1413cf3dba4fad5ce6072ef863..a5122fa4bf4d1afa7ac8f821b8b87ba88d2617b6 100644 (file)
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -514,6 +514,20 @@ static struct vfio_group *vfio_group_find_or_alloc(struct device *dev)
        return group;
 }
 
+static void vfio_device_group_register(struct vfio_device *device)
+{
+       mutex_lock(&device->group->device_lock);
+       list_add(&device->group_next, &device->group->device_list);
+       mutex_unlock(&device->group->device_lock);
+}
+
+static void vfio_device_group_unregister(struct vfio_device *device)
+{
+       mutex_lock(&device->group->device_lock);
+       list_del(&device->group_next);
+       mutex_unlock(&device->group->device_lock);
+}
+
 static int __vfio_register_dev(struct vfio_device *device,
                struct vfio_group *group)
 {
@@ -552,9 +566,7 @@ static int __vfio_register_dev(struct vfio_device *device,
        /* Refcounting can't start until the driver calls register */
        refcount_set(&device->refcount, 1);
 
-       mutex_lock(&group->device_lock);
-       list_add(&device->group_next, &group->device_list);
-       mutex_unlock(&group->device_lock);
+       vfio_device_group_register(device);
 
        return 0;
 err_out:
@@ -614,7 +626,6 @@ static struct vfio_device *vfio_device_get_from_name(struct vfio_group *group,
  * removed.  Open file descriptors for the device... */
 void vfio_unregister_group_dev(struct vfio_device *device)
 {
-       struct vfio_group *group = device->group;
        unsigned int i = 0;
        bool interrupted = false;
        long rc;
@@ -642,9 +653,7 @@ void vfio_unregister_group_dev(struct vfio_device *device)
                }
        }
 
-       mutex_lock(&group->device_lock);
-       list_del(&device->group_next);
-       mutex_unlock(&group->device_lock);
+       vfio_device_group_unregister(device);
 
        /* Balances device_add in register path */
        device_del(&device->device);