From d76123eb357a4baa653714183df286c1bb99f707 Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Fri, 27 Apr 2007 16:01:37 +0200 Subject: [S390] cio: ccwgroup register vs. unregister. Introduce a mutex for struct ccwgroup to prevent simuntaneous register/unregister on the same ccwgroup device. Signed-off-by: Cornelia Huck Signed-off-by: Martin Schwidefsky --- drivers/s390/cio/ccwgroup.c | 33 ++++++++++++++++++--------------- 1 file changed, 18 insertions(+), 15 deletions(-) (limited to 'drivers/s390/cio/ccwgroup.c') diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c index 5aeb68e732b..e5ccda63e88 100644 --- a/drivers/s390/cio/ccwgroup.c +++ b/drivers/s390/cio/ccwgroup.c @@ -75,8 +75,10 @@ static void ccwgroup_ungroup_callback(struct device *dev) { struct ccwgroup_device *gdev = to_ccwgroupdev(dev); + mutex_lock(&gdev->reg_mutex); __ccwgroup_remove_symlinks(gdev); device_unregister(dev); + mutex_unlock(&gdev->reg_mutex); } static ssize_t @@ -173,7 +175,8 @@ ccwgroup_create(struct device *root, return -ENOMEM; atomic_set(&gdev->onoff, 0); - + mutex_init(&gdev->reg_mutex); + mutex_lock(&gdev->reg_mutex); for (i = 0; i < argc; i++) { gdev->cdev[i] = get_ccwdev_by_busid(cdrv, argv[i]); @@ -183,12 +186,12 @@ ccwgroup_create(struct device *root, || gdev->cdev[i]->id.driver_info != gdev->cdev[0]->id.driver_info) { rc = -EINVAL; - goto free_dev; + goto error; } /* Don't allow a device to belong to more than one group. */ if (gdev->cdev[i]->dev.driver_data) { rc = -EINVAL; - goto free_dev; + goto error; } gdev->cdev[i]->dev.driver_data = gdev; } @@ -203,9 +206,8 @@ ccwgroup_create(struct device *root, gdev->cdev[0]->dev.bus_id); rc = device_register(&gdev->dev); - if (rc) - goto free_dev; + goto error; get_device(&gdev->dev); rc = device_create_file(&gdev->dev, &dev_attr_ungroup); @@ -216,27 +218,21 @@ ccwgroup_create(struct device *root, rc = __ccwgroup_create_symlinks(gdev); if (!rc) { + mutex_unlock(&gdev->reg_mutex); put_device(&gdev->dev); return 0; } device_remove_file(&gdev->dev, &dev_attr_ungroup); device_unregister(&gdev->dev); error: - for (i = 0; i < argc; i++) - if (gdev->cdev[i]) { - put_device(&gdev->cdev[i]->dev); - gdev->cdev[i]->dev.driver_data = NULL; - } - put_device(&gdev->dev); - return rc; -free_dev: for (i = 0; i < argc; i++) if (gdev->cdev[i]) { if (gdev->cdev[i]->dev.driver_data == gdev) gdev->cdev[i]->dev.driver_data = NULL; put_device(&gdev->cdev[i]->dev); } - kfree(gdev); + mutex_unlock(&gdev->reg_mutex); + put_device(&gdev->dev); return rc; } @@ -422,8 +418,12 @@ ccwgroup_driver_unregister (struct ccwgroup_driver *cdriver) get_driver(&cdriver->driver); while ((dev = driver_find_device(&cdriver->driver, NULL, NULL, __ccwgroup_match_all))) { - __ccwgroup_remove_symlinks(to_ccwgroupdev(dev)); + struct ccwgroup_device *gdev = to_ccwgroupdev(dev); + + mutex_lock(&gdev->reg_mutex); + __ccwgroup_remove_symlinks(gdev); device_unregister(dev); + mutex_unlock(&gdev->reg_mutex); put_device(dev); } put_driver(&cdriver->driver); @@ -444,8 +444,10 @@ __ccwgroup_get_gdev_by_cdev(struct ccw_device *cdev) if (cdev->dev.driver_data) { gdev = (struct ccwgroup_device *)cdev->dev.driver_data; if (get_device(&gdev->dev)) { + mutex_lock(&gdev->reg_mutex); if (device_is_registered(&gdev->dev)) return gdev; + mutex_unlock(&gdev->reg_mutex); put_device(&gdev->dev); } return NULL; @@ -465,6 +467,7 @@ ccwgroup_remove_ccwdev(struct ccw_device *cdev) if (gdev) { __ccwgroup_remove_symlinks(gdev); device_unregister(&gdev->dev); + mutex_unlock(&gdev->reg_mutex); put_device(&gdev->dev); } } -- cgit v1.2.3