vfio: Make vfio_device_open() truly device specific

Then move group related logic into vfio_device_open_file(). Accordingly
introduce a vfio_device_close() to pair up.

Link: https://lore.kernel.org/r/20221201145535.589687-7-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 5dddf962f65092ba6d42744973253760571ccf78..37413ac254c0abf5740c6210f52070da3d788c6f 100644 (file)
--- a/drivers/vfio/vfio_main.c
+++ b/drivers/vfio/vfio_main.c
@@ -855,20 +855,41 @@ static void vfio_device_last_close(struct vfio_device *device)
        module_put(device->dev->driver->owner);
 }
 
-static struct file *vfio_device_open(struct vfio_device *device)
+static int vfio_device_open(struct vfio_device *device)
 {
-       struct file *filep;
-       int ret;
+       int ret = 0;
 
        mutex_lock(&device->dev_set->lock);
        device->open_count++;
        if (device->open_count == 1) {
                ret = vfio_device_first_open(device);
                if (ret)
-                       goto err_unlock;
+                       device->open_count--;
        }
        mutex_unlock(&device->dev_set->lock);
 
+       return ret;
+}
+
+static void vfio_device_close(struct vfio_device *device)
+{
+       mutex_lock(&device->dev_set->lock);
+       vfio_assert_device_open(device);
+       if (device->open_count == 1)
+               vfio_device_last_close(device);
+       device->open_count--;
+       mutex_unlock(&device->dev_set->lock);
+}
+
+static struct file *vfio_device_open_file(struct vfio_device *device)
+{
+       struct file *filep;
+       int ret;
+
+       ret = vfio_device_open(device);
+       if (ret)
+               goto err_out;
+
        /*
         * We can't use anon_inode_getfd() because we need to modify
         * the f_mode flags directly to allow more than just ioctls
@@ -897,12 +918,8 @@ static struct file *vfio_device_open(struct vfio_device *device)
        return filep;
 
 err_close_device:
-       mutex_lock(&device->dev_set->lock);
-       if (device->open_count == 1)
-               vfio_device_last_close(device);
-err_unlock:
-       device->open_count--;
-       mutex_unlock(&device->dev_set->lock);
+       vfio_device_close(device);
+err_out:
        return ERR_PTR(ret);
 }
 
@@ -930,7 +947,7 @@ static int vfio_group_ioctl_get_device_fd(struct vfio_group *group,
                goto err_put_device;
        }
 
-       filep = vfio_device_open(device);
+       filep = vfio_device_open_file(device);
        if (IS_ERR(filep)) {
                ret = PTR_ERR(filep);
                goto err_put_fdno;
@@ -1113,12 +1130,7 @@ 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);
-       vfio_assert_device_open(device);
-       if (device->open_count == 1)
-               vfio_device_last_close(device);
-       device->open_count--;
-       mutex_unlock(&device->dev_set->lock);
+       vfio_device_close(device);
 
        vfio_device_put_registration(device);