diff options
Diffstat (limited to 'drivers/s390/char/tape_core.c')
-rw-r--r-- | drivers/s390/char/tape_core.c | 65 |
1 files changed, 32 insertions, 33 deletions
diff --git a/drivers/s390/char/tape_core.c b/drivers/s390/char/tape_core.c index 5cd31e07164..f5d6802dc5d 100644 --- a/drivers/s390/char/tape_core.c +++ b/drivers/s390/char/tape_core.c @@ -492,6 +492,7 @@ tape_alloc_device(void) kfree(device); return ERR_PTR(-ENOMEM); } + mutex_init(&device->mutex); INIT_LIST_HEAD(&device->req_queue); INIT_LIST_HEAD(&device->node); init_waitqueue_head(&device->state_change_wq); @@ -511,11 +512,12 @@ tape_alloc_device(void) * increment the reference count. */ struct tape_device * -tape_get_device_reference(struct tape_device *device) +tape_get_device(struct tape_device *device) { - DBF_EVENT(4, "tape_get_device_reference(%p) = %i\n", device, - atomic_inc_return(&device->ref_count)); + int count; + count = atomic_inc_return(&device->ref_count); + DBF_EVENT(4, "tape_get_device(%p) = %i\n", device, count); return device; } @@ -525,32 +527,25 @@ tape_get_device_reference(struct tape_device *device) * The function returns a NULL pointer to be used by the caller * for clearing reference pointers. */ -struct tape_device * +void tape_put_device(struct tape_device *device) { - int remain; + int count; - remain = atomic_dec_return(&device->ref_count); - if (remain > 0) { - DBF_EVENT(4, "tape_put_device(%p) -> %i\n", device, remain); - } else { - if (remain < 0) { - DBF_EVENT(4, "put device without reference\n"); - } else { - DBF_EVENT(4, "tape_free_device(%p)\n", device); - kfree(device->modeset_byte); - kfree(device); - } + count = atomic_dec_return(&device->ref_count); + DBF_EVENT(4, "tape_put_device(%p) -> %i\n", device, count); + BUG_ON(count < 0); + if (count == 0) { + kfree(device->modeset_byte); + kfree(device); } - - return NULL; } /* * Find tape device by a device index. */ struct tape_device * -tape_get_device(int devindex) +tape_find_device(int devindex) { struct tape_device *device, *tmp; @@ -558,7 +553,7 @@ tape_get_device(int devindex) read_lock(&tape_device_lock); list_for_each_entry(tmp, &tape_device_list, node) { if (tmp->first_minor / TAPE_MINORS_PER_DEV == devindex) { - device = tape_get_device_reference(tmp); + device = tape_get_device(tmp); break; } } @@ -579,7 +574,8 @@ tape_generic_probe(struct ccw_device *cdev) device = tape_alloc_device(); if (IS_ERR(device)) return -ENODEV; - ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP); + ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP | + CCWDEV_DO_MULTIPATH); ret = sysfs_create_group(&cdev->dev.kobj, &tape_attr_group); if (ret) { tape_put_device(device); @@ -606,7 +602,8 @@ __tape_discard_requests(struct tape_device *device) list_del(&request->list); /* Decrease ref_count for removed request. */ - request->device = tape_put_device(device); + request->device = NULL; + tape_put_device(device); request->rc = -EIO; if (request->callback != NULL) request->callback(request, request->callback_data); @@ -664,9 +661,11 @@ tape_generic_remove(struct ccw_device *cdev) tape_cleanup_device(device); } - if (!dev_get_drvdata(&cdev->dev)) { + device = dev_get_drvdata(&cdev->dev); + if (device) { sysfs_remove_group(&cdev->dev.kobj, &tape_attr_group); - dev_set_drvdata(&cdev->dev, tape_put_device(dev_get_drvdata(&cdev->dev))); + dev_set_drvdata(&cdev->dev, NULL); + tape_put_device(device); } } @@ -721,9 +720,8 @@ tape_free_request (struct tape_request * request) { DBF_LH(6, "Free request %p\n", request); - if (request->device != NULL) { - request->device = tape_put_device(request->device); - } + if (request->device) + tape_put_device(request->device); kfree(request->cpdata); kfree(request->cpaddr); kfree(request); @@ -838,7 +836,8 @@ static void tape_long_busy_timeout(unsigned long data) BUG_ON(request->status != TAPE_REQUEST_LONG_BUSY); DBF_LH(6, "%08x: Long busy timeout.\n", device->cdev_id); __tape_start_next_request(device); - device->lb_timeout.data = (unsigned long) tape_put_device(device); + device->lb_timeout.data = 0UL; + tape_put_device(device); spin_unlock_irq(get_ccwdev_lock(device->cdev)); } @@ -918,7 +917,7 @@ __tape_start_request(struct tape_device *device, struct tape_request *request) } /* Increase use count of device for the added request. */ - request->device = tape_get_device_reference(device); + request->device = tape_get_device(device); if (list_empty(&device->req_queue)) { /* No other requests are on the queue. Start this one. */ @@ -1117,8 +1116,8 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb) if (req->status == TAPE_REQUEST_LONG_BUSY) { DBF_EVENT(3, "(%08x): del timer\n", device->cdev_id); if (del_timer(&device->lb_timeout)) { - device->lb_timeout.data = (unsigned long) - tape_put_device(device); + device->lb_timeout.data = 0UL; + tape_put_device(device); __tape_start_next_request(device); } return; @@ -1173,7 +1172,7 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb) break; case TAPE_IO_LONG_BUSY: device->lb_timeout.data = - (unsigned long)tape_get_device_reference(device); + (unsigned long) tape_get_device(device); device->lb_timeout.expires = jiffies + LONG_BUSY_TIMEOUT * HZ; DBF_EVENT(3, "(%08x): add timer\n", device->cdev_id); @@ -1326,7 +1325,7 @@ EXPORT_SYMBOL(tape_generic_online); EXPORT_SYMBOL(tape_generic_offline); EXPORT_SYMBOL(tape_generic_pm_suspend); EXPORT_SYMBOL(tape_put_device); -EXPORT_SYMBOL(tape_get_device_reference); +EXPORT_SYMBOL(tape_get_device); EXPORT_SYMBOL(tape_state_verbose); EXPORT_SYMBOL(tape_op_verbose); EXPORT_SYMBOL(tape_state_set); |