diff options
| -rw-r--r-- | drivers/s390/block/dasd.c | 63 |
1 files changed, 55 insertions, 8 deletions
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 4195cc05efeb..82758cbb220b 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -2752,6 +2752,26 @@ static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data) } /* + * Requeue a request back to the block request queue + * only works for block requests + */ +static int _dasd_requeue_request(struct dasd_ccw_req *cqr) +{ + struct dasd_block *block = cqr->block; + struct request *req; + unsigned long flags; + + if (!block) + return -EINVAL; + spin_lock_irqsave(&block->queue_lock, flags); + req = (struct request *) cqr->callback_data; + blk_requeue_request(block->request_queue, req); + spin_unlock_irqrestore(&block->queue_lock, flags); + + return 0; +} + +/* * Go through all request on the dasd_block request queue, cancel them * on the respective dasd_device, and return them to the generic * block layer. @@ -3469,10 +3489,11 @@ EXPORT_SYMBOL_GPL(dasd_generic_verify_path); int dasd_generic_pm_freeze(struct ccw_device *cdev) { + struct dasd_device *device = dasd_device_from_cdev(cdev); + struct list_head freeze_queue; struct dasd_ccw_req *cqr, *n; + struct dasd_ccw_req *refers; int rc; - struct list_head freeze_queue; - struct dasd_device *device = dasd_device_from_cdev(cdev); if (IS_ERR(device)) return PTR_ERR(device); @@ -3485,7 +3506,8 @@ int dasd_generic_pm_freeze(struct ccw_device *cdev) /* disallow new I/O */ dasd_device_set_stop_bits(device, DASD_STOPPED_PM); - /* clear active requests */ + + /* clear active requests and requeue them to block layer if possible */ INIT_LIST_HEAD(&freeze_queue); spin_lock_irq(get_ccwdev_lock(cdev)); rc = 0; @@ -3505,7 +3527,6 @@ int dasd_generic_pm_freeze(struct ccw_device *cdev) } list_move_tail(&cqr->devlist, &freeze_queue); } - spin_unlock_irq(get_ccwdev_lock(cdev)); list_for_each_entry_safe(cqr, n, &freeze_queue, devlist) { @@ -3513,12 +3534,38 @@ int dasd_generic_pm_freeze(struct ccw_device *cdev) (cqr->status != DASD_CQR_CLEAR_PENDING)); if (cqr->status == DASD_CQR_CLEARED) cqr->status = DASD_CQR_QUEUED; + + /* requeue requests to blocklayer will only work for + block device requests */ + if (_dasd_requeue_request(cqr)) + continue; + + /* remove requests from device and block queue */ + list_del_init(&cqr->devlist); + while (cqr->refers != NULL) { + refers = cqr->refers; + /* remove the request from the block queue */ + list_del(&cqr->blocklist); + /* free the finished erp request */ + dasd_free_erp_request(cqr, cqr->memdev); + cqr = refers; + } + if (cqr->block) + list_del_init(&cqr->blocklist); + cqr->block->base->discipline->free_cp( + cqr, (struct request *) cqr->callback_data); } - /* move freeze_queue to start of the ccw_queue */ - spin_lock_irq(get_ccwdev_lock(cdev)); - list_splice_tail(&freeze_queue, &device->ccw_queue); - spin_unlock_irq(get_ccwdev_lock(cdev)); + /* + * if requests remain then they are internal request + * and go back to the device queue + */ + if (!list_empty(&freeze_queue)) { + /* move freeze_queue to start of the ccw_queue */ + spin_lock_irq(get_ccwdev_lock(cdev)); + list_splice_tail(&freeze_queue, &device->ccw_queue); + spin_unlock_irq(get_ccwdev_lock(cdev)); + } dasd_put_device(device); return rc; } |