drm: add core support for unplugging a device (v2)

Two parts to this, one is simple unplug from sysfs for the device node.

The second adds an unplugged state, if we have device opens, we
just set the unplugged state and return, if we have no device
opens we drop the drm device.

If after a lastclose we discover we are unplugged we then
drop the drm device.

v2: use an atomic for unplugged and wrap it for users,
add checks on open + mmap + ioctl entry points.

Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Dave Airlie
2012-02-20 14:18:07 +00:00
parent cbc7e22151
commit 2c07a21d6f
6 changed files with 57 additions and 0 deletions

View File

@@ -133,6 +133,9 @@ int drm_open(struct inode *inode, struct file *filp)
if (!(dev = minor->dev))
return -ENODEV;
if (drm_device_is_unplugged(dev))
return -ENODEV;
retcode = drm_open_helper(inode, filp, dev);
if (!retcode) {
atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
@@ -181,6 +184,9 @@ int drm_stub_open(struct inode *inode, struct file *filp)
if (!(dev = minor->dev))
goto out;
if (drm_device_is_unplugged(dev))
goto out;
old_fops = filp->f_op;
filp->f_op = fops_get(dev->driver->fops);
if (filp->f_op == NULL) {
@@ -579,6 +585,8 @@ int drm_release(struct inode *inode, struct file *filp)
retcode = -EBUSY;
} else
retcode = drm_lastclose(dev);
if (drm_device_is_unplugged(dev))
drm_put_dev(dev);
}
mutex_unlock(&drm_global_mutex);